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Sample records for secondary mineral microtextures

  1. Chronostratigraphy of Monte Vulture volcano (southern Italy): secondary mineral microtextures and 39Ar-40Ar systematics

    NASA Astrophysics Data System (ADS)

    Villa, Igor M.; Buettner, Annett

    2009-12-01

    The eruptive history of Monte Vulture has been the subject of several geochronological investigations during the past decades, which reliably dated only a small number of eruptions. Understanding the causes of sub-optimum data yield in the past requires an interdisciplinary approach. We re-analyzed samples from previous works and present new data on samples from the main volcano-stratigraphic units of Monte Vulture, so as to provide an improved, consistent chronostratigraphic database. Imaging of minerals by cathodoluminescence and backscattered electrons reveals that heterochemical, high-temperature deuteric reaction textures are ubiquitous. Such observations are common in metamorphic rocks but had not frequently been reported from volcanic rocks. In view of the mineralogical complexity, we base our chronological interpretation on isochemical steps, defined as steps for which the Cl/K and/or the Ca/K ratios are constant. Isochemical steps carry the isotopic signature of chemically homogeneous mineral phases and therefore allow a well-constrained age interpretation. Comparison of old and new 39Ar-40Ar data proves the reproducibility of age spectra and their shapes. This quantifies the analytical reliability of the irradiation and mass-spectrometric analyses. Anomalous age spectra are a reproducible property of some specific samples and correlate with mineralogical anomalies. The present data allow us to fine-tune the age of the volcanostratigraphic units of Monte Vulture during the known interval of main volcanic activity from ca. 740 to 610 ka. After a very long stasis, the volcanic activity in the Monte Vulture area resumed with diatremic eruptions, one of which (Lago Piccolo di Monticchio, the site of a palynological-paleoclimatological drilling) was dated at ca. 140 ka.

  2. Heavy Minerals in Palaeotsunami Deposits: Assemblages, Spatial Distribution and Microtextural Imprints

    NASA Astrophysics Data System (ADS)

    Costa, P. J.; Andrade, C.; Cascalho, J.; Dawson, A. G.; Freitas, M. C.; Dawson, S.; Mahaney, W. C.

    2013-12-01

    more likely source areas. In addition, preliminary results of SEM analysis of microtextural features imprinted in the surface of heavy minerals indicate an increase in the number of mechanical marks in the surface of palaeotsunami grains when compared with potential source materials (beach, dune, inshore and offshore samples). This work further reveals the potential to use heavy minerals as a complementary sedimentological tool in the study of palaeotsunami deposits.

  3. The response of mineralizing culture systems to microtextured and polished titanium surfaces.

    PubMed

    Hacking, S Adam; Harvey, Edward; Roughley, Peter; Tanzer, Michael; Bobyn, John

    2008-10-01

    The surface texture of titanium has a predictable effect on peri-implant tissue formation in vivo. When implanted in an osseous environment, smooth surfaces (R(a) < 0.5 mm) are generally apposed by fibrous tissue and textured surfaces (R(a) > 1.0 mm) are generally apposed by osseous tissue. Thus in vitro study assessed the mineralization and proliferation response of TF274, MC3T3-E1, murine femoral stromal cells and canine stromal cells to tissue culture plastic (R(a) = 0.001 mm), polished (R(a) = 0.01 mm) and irregularly textured (R(a) = 3.26 mm) titanium surfaces. Amongst all culture systems, proliferation was significantly decreased on textured vs. smooth surfaces. Midway through the culture of the canine marrow cells, the cell layer detached from the tissue culture plastic and polished titanium surfaces. The TF274, MC3T3-E1, murine femoral stromal cell systems formed a mineralized matrix on the tissue culture plastic and polished titanium surfaces which was not observed with the canine stromal cell system. Compared to the tissue culture plastic and polished titanium surfaces, matrix mineralization was significantly reduced on the textured titanium surfaces for the TF274, MC3T3-E1, murine femoral stromal systems, a result which was differed significantly in comparison to the canine stromal system. These results were surprising given the large number of reports concerning the in vivo response to titanium in clinical and pre-clinical studies. Further work is required to determine if the TF274, MC3T3-E1 and murine femoral stromal systems are suitable for the in vitro investigation of the effects of titanium surface texture on osteoblast activity.

  4. Weathering and Secondary Minerals in the Martian Meteorite Shergotty

    NASA Technical Reports Server (NTRS)

    Wentworth, Susan J.; Thomas-Keprta, Kathie L.; McKay, David S.

    2000-01-01

    The Shergotty martian meteorite contains weathering features and secondary minerals much like those in Nakhla, including secondary silicates, NaCl, and Ca-sulfate. It is likely that the weathering occurred on Mars.

  5. Mars weathering analogs - Secondary mineralization in Antarctic basalts

    NASA Technical Reports Server (NTRS)

    Berkley, J. L.

    1982-01-01

    Alkalic basalt samples from Ross Island, Antarctica, are evaluated as terrestrial analogs to weathered surface materials on Mars. Secondary alteration in the rocks is limited to pneumatolytic oxidation of igneous minerals and glass, rare groundmass clay and zeolite mineralization, and hydrothermal minerals coating fractures and vesicle surfaces. Hydrothermal mineral assemblages consist mainly of K-feldspar, zeolites (phillipsite and chabazite), calcite, and anhydrite. Low alteration rates are attributed to cold and dry environmental factors common to both Antarctica and Mars. It is noted that mechanical weathering (aeolian abrasion) of Martian equivalents to present Antarctic basalts would yield minor hydrothermal minerals and local surface fines composed of primary igneous minerals and glass but would produce few hydrous products, such as palagonite, clay or micas. It is thought that leaching of hydrothermal vein minerals by migrating fluids and redeposition in duricrust deposits may represent an alternate process for incorporating secondary minerals of volcanic origin into Martian surface fines.

  6. Ion beam microtexturing and enhanced surface diffusion

    NASA Technical Reports Server (NTRS)

    Robinson, R. S.

    1982-01-01

    Ion beam interactions with solid surfaces are discussed with particular emphasis on microtexturing induced by the deliberate deposition of controllable amounts of an impurity material onto a solid surface while simultaneously sputtering the surface with an ion beam. Experimental study of the optical properties of microtextured surfaces is described. Measurements of both absorptance as a function of wavelength and emissivity are presented. A computer code is described that models the sputtering and ion reflection processes involved in microtexture formation.

  7. Spatial statistical characterization and simulation of microtexture

    NASA Astrophysics Data System (ADS)

    Sparkman, Daniel Murray

    Microtexture has been found to affect the macro-scale behavior of materials in many ways. For example, in titanium alloys, microtexture regions are preferential sites of fatigue crack formation. Also, yield strength and fatigue life have been shown to be affected by the microtexture. Despite the consensus on the importance of the presence of microtextured regions in polycrystals, no standard methods exist to statistically characterize these regions. The only published method for simulation of microtexture does not take into account the spatial nature of the regions. In this work, it is proposed that microtexture may be characterized with spatial statistics. Methods were also developed for simulation of microtexture. Characterization of microtexture regions allows for quantitative comparison of different materials and different thermal-mechanical processing routes. Simulation of microtexture regions allows for prediction of bulk material properties from micro-scale models. Combining the characterization and simulation methods proposed in this work will allow for optimization of material processing for improved material properties and performance.

  8. Bisphosphonates do not alter the rate of secondary mineralization

    SciTech Connect

    Fuchs R. K.; Miller L.; Faillace M.E.; Allen M.R.; Phipps R.J. and Burr D.B.

    2011-05-18

    Bisphosphonates function to reduce bone turnover, which consequently increases the mean degree of tissue mineralization at an organ level. However, it is not clear if bisphosphonates alter the length of time required for an individual bone-modeling unit (BMU) to fully mineralize. We have recently demonstrated that it takes {approx}350 days (d) for normal, untreated cortical bone to fully mineralize. The aim of this study was to determine the rate at which newly formed trabecular BMUs become fully mineralized in rabbits treated for up to 414 d with clinical doses of either risedronate (RIS) or alendronate (ALN). Thirty-six, 4-month old virgin female New Zealand white rabbits were allocated to RIS (n = 12; 2.4 {micro}g/kg body weight), ALN (n = 12; 2.4 {micro}g/kg body weight), or volume-matched saline controls (CON; n = 12). Fluorochrome labels were administered at specific time intervals to quantify the rate and level of mineralization of trabecular bone from the femoral neck (FN) by Fourier transform infrared microspectroscopy (FTIRM). The organic (collagen) and inorganic (phosphate and carbonate) IR spectral characteristics of trabecular bone from undecalcified 4 micron thick tissue sections were quantified from fluorescently labels regions that had mineralized for 1, 8, 18, 35, 70, 105, 140, 210, 280, and 385 d (4 rabbits per time point and treatment group). All groups exhibited a rapid increase in mineralization over the first 18 days, the period of primary mineralization, with no significant differences between treatments. Mineralization continued to increase, at a slower rate up, to 385 days (secondary mineralization), and was not different among treatments. There were no significant differences between treatments for the rate of mineralization within an individual BMU; however, ALN and RIS both increased global tissue mineralization as demonstrated by areal bone mineral density from DXA. We conclude that increases in tissue mineralization that occur

  9. Bisphosphonates do not Alter the Rate of Secondary Mineralization

    SciTech Connect

    R Fuchs; M Faillace; M Allen; R Phipps; L Miller; D Burr

    2011-12-31

    Bisphosphonates function to reduce bone turnover, which consequently increases the mean degree of tissue mineralization at an organ level. However, it is not clear if bisphosphonates alter the length of time required for an individual bone-modeling unit (BMU) to fully mineralize. We have recently demonstrated that it takes {approx}350 days (d) for normal, untreated cortical bone to fully mineralize. The aim of this study was to determine the rate at which newly formed trabecular BMUs become fully mineralized in rabbits treated for up to 414 d with clinical doses of either risedronate (RIS) or alendronate (ALN). Thirty-six, 4-month old virgin female New Zealand white rabbits were allocated to RIS (n=12; 2.4 {mu}g/kg body weight), ALN (n=12; 2.4 {mu}g/kg body weight), or volume-matched saline controls (CON; n=12). Fluorochrome labels were administered at specific time intervals to quantify the rate and level of mineralization of trabecular bone from the femoral neck (FN) by Fourier transform infrared microspectroscopy (FTIRM). The organic (collagen) and inorganic (phosphate and carbonate) IR spectral characteristics of trabecular bone from undecalcified 4 micron thick tissue sections were quantified from fluorescently labels regions that had mineralized for 1, 8, 18, 35, 70, 105, 140, 210, 280, and 385 d (4 rabbits per time point and treatment group). All groups exhibited a rapid increase in mineralization over the first 18 days, the period of primary mineralization, with no significant differences between treatments. Mineralization continued to increase, at a slower rate up, to 385 days (secondary mineralization), and was not different among treatments. There were no significant differences between treatments for the rate of mineralization within an individual BMU; however, ALN and RIS both increased global tissue mineralization as demonstrated by areal bone mineral density from DXA. We conclude that increases in tissue mineralization that occur following a period

  10. Microtextural analysis of quartz grains of tsunami and non-tsunami deposits - A case study from Tirúa (Chile)

    NASA Astrophysics Data System (ADS)

    Bellanova, Piero; Bahlburg, Heinrich; Nentwig, Vanessa; Spiske, Michaela

    2016-08-01

    In order to estimate the tsunami hazard it is essential to reliably identify and differentiate tsunami deposits from other high-energy events like storms. Recently, the microtextural analysis of quartz grain surfaces was introduced as a method to differentiate between tsunami and other deposits. Using tsunami deposits sampled from a bank profile of the Tirúa river (central Chile), an area that was significantly affected by the 2010 and 1960 Chile tsunamis, we tested the microtextural analysis method for its capability to identify tsunami deposits. A total of 815 quartz grain surfaces of two tsunami layers, two non-tsunami marsh sediment samples, and three reference samples from nearby beach, dune and river were analyzed using scanning electron microscopy (SEM). We grouped the detected microtexture features into five microtextural families: angularity, fresh surfaces, percussion marks, adhering particles and dissolution features. Both the tsunami deposits and reference samples reveal high numbers of fresh surfaces and percussion marks. Thus, there are no statistically significant differences between tsunami, beach, dune and river deposits in characteristics and abundances in all microtextural families. Our study indicates that the microtextural analysis of quartz grains may not be a suitable method to identify tsunami deposits in Tirúa (Chile), due to local factors such as high numbers of inherited microtextures and the possible effects of the high amount of heavy minerals.

  11. Secondary sulfate minerals from Alum Cave Bluff: Microscopy and microanalysis

    SciTech Connect

    Lauf, R.J.

    1997-07-01

    Microcrystals of secondary sulfate minerals from Alum Cave Bluff, Great Smoky Mountains National Park, were examined by scanning electron microscopy and identified by X-ray fluorescence (XRF) in the SEM. Among the samples the author discovered three new rare-earth sulfates: coskrenite-(Ce), levinsonite-(Y), and zugshunstite-(Ce). Other minerals illustrated in this report include sulfur, tschermigite, gypsum, epsomite, melanterite, halotrichite, apjohnite, jarosite, slavikite, magnesiocopiapite, and diadochite. Additional specimens whose identification is more tentative include pickeringite, aluminite, basaluminite, and botryogen. Alum Cave is a ``Dana locality`` for apjohnite and potash alum, and is the first documented North American occurrence of slavikite.

  12. Martian surface microtexture from orbital observations

    NASA Astrophysics Data System (ADS)

    Fernando, J.; Schmidt, F.; Douté, S.

    2015-10-01

    The information about the surface microtexture is useful to constrain the geological processes (e.g., transportation, deposition, weathering). In this study, the grain microtexture is derived from the orbital CRISM/MRO multi-angular observations allowing to characterize the surface scattering behavior. The Hapke radiative transfer model is inverted to derive the photometric parameters which have physical meanings (e.g., grain size, roughness, shape, internal structure). Eight sites having various geological contexts are selected. The results show a high diversity of grain microtexture. This result put forward that Mars have experimented various geological processes. The link between information about the grain microtexture and the geological processes will be presented at the conference.

  13. Secondary hydrothermal mineral system in the Campi Flegrei caldera, Italy

    NASA Astrophysics Data System (ADS)

    Mormone, A.; Piochi, M.; Di Vito, M. A.; Troise, C.; De Natale, G.

    2012-04-01

    Mineral systems generally develop around the deep root of the volcanoes down to the degassing magma chamber due the selective enrichment process of elements within the host-rock. The mineralization process depends on i) volcanic structure, ii) magma and fluid chemistry, iii) host-rock type and texture, iv) temperature and pressure conditions, and v) action timing that affect the transport and precipitation conditions of elements in the solution. Firstly, it generates a hydrothermal system that in a later phase may generate considerable metallogenic mineralization, in terms of both spatial extension and specie abundance. The study of secondary assemblages through depth and, possibly, through time, together with the definition of the general geological, structural, mineralogical and petrological context is the background to understand the genesis of mineral-to-metallogenic systems. We report our study on the Campi Flegrei volcano of potassic Southern Italy belt. It is a sub-circular caldera characterized by an active high-temperature and fluid-rich geothermal system affected by seismicity and ground deformation in the recent decades. The circulating fluids originate at deeper level within a degassing magma body and give rise at the surface up to 1500 tonnes/day of CO2 emissions. Their composition is intermediate between meteoric water and brines. Saline-rich fluids have been detected at ~3000 in downhole. The hydrothermal alteration varies from argillitic to phillitic, nearby the caldera boundary, to propilitic to thermo-metamorphic facies towards its centre. The Campi Flegrei caldera was defined as analogue of mineralized system such as White Island (New Zealand) that is an example of an active magmatic and embryonic copper porphyry system. In order to enhance the knowledge of such a type of embryonic-like metallogenic system, we have carried out macroscopic and microscopic investigations, SEM-EDS and electron microprobe analyses on selected samples from deep wells

  14. Origin of secondary sulfate minerals on active andesitic stratovolcanoes

    USGS Publications Warehouse

    Zimbelman, D.R.; Rye, R.O.; Breit, G.N.

    2005-01-01

    Sulfate minerals in altered rocks on the upper flanks and summits of active andesitic stratovolcanoes result from multiple processes. The origin of these sulfates at five active volcanoes, Citlalte??petl (Mexico), and Mount Adams, Hood, Rainier, and Shasta (Cascade Range, USA), was investigated using field observations, petrography, mineralogy, chemical modeling, and stable-isotope data. The four general groups of sulfate minerals identified are: (1) alunite group, (2) jarosite group, (3) readily soluble Fe- and Al-hydroxysulfates, and (4) simple alkaline-earth sulfates such as anhydrite, gypsum, and barite. Generalized assemblages of spatially associated secondary minerals were recognized: (1) alunite+silica??pyrite??kaolinite?? gypsum??sulfur, (2) jarosite+alunite+silica; (3) jarosite+smectite+silica??pyrite, (4) Fe- and Al-hydroxysulfates+silica, and (5) simple sulfates+silica??Al-hydroxysulfates??alunite. Isotopic data verify that all sulfate and sulfide minerals and their associated alteration assemblages result largely from the introduction of sulfur-bearing magmatic gases into meteoric water in the upper levels of the volcanoes. The sulfur and oxygen isotopic data for all minerals indicate the general mixing of aqueous sulfate derived from deep (largely disproportionation of SO2 in magmatic vapor) and shallow (oxidation of pyrite or H2S) sources. The hydrogen and oxygen isotopic data of alunite indicate the mixing of magmatic and meteoric fluids. Some alunite-group minerals, along with kaolinite, formed from sulfuric acid created by the disproportionation of SO2 in a condensing magmatic vapor. Such alunite, observed only in those volcanoes whose interiors are exposed by erosion or edifice collapse, may have ??34S values that reflect equilibrium (350??50 ??C) between aqueous sulfate and H2S. Alunite with ??34S values indicating disequilibrium between parent aqueous sulfate and H2S may form from aqueous sulfate created in higher level low

  15. Formation of secondary minerals in a lysimeter approach - A mineral-microbe interaction

    NASA Astrophysics Data System (ADS)

    Schäffner, F.; Merten, D.; De Giudici, G.; Beyer, A.; Akob, D. M.; Ricci, P. C.; Küsel, K.; Büchel, G.

    2012-04-01

    Heavy metal contamination of large areas due to uranium mining operations poses a serious long-term environmental problem. In the Ronneburg district (eastern Thuringia, Germany), leaching of low grade uranium bearing ores (uranium content < 300 g/t) occurred from 1972 to 1990 using acid mine drainage (AMD; pH 2.7-2.8) and diluted sulphuric acid (10 g/l). Secondary mineral phases like birnessite, todorokite and goethite occur within a natural attenuation process associated with enrichment of heavy metals, especially Cd, Ni, Co, Cu and Zn due to a residual contamination even after remediation efforts. To reveal the processes of secondary mineral precipitation in the field a laboratory lysimeter approach was set up under in situ-like conditions. Homogenized soil from the field site and pure quartz sand were used as substrates. In general, in situ measurements of redox potentials in the substrates showed highly oxidizing conditions (200-750 mV). Water was supplied to the lysimeter from below via a mariottés bottle containing contaminated groundwater from the field. Evaporation processes were allowed, providing a continuous flow of water. This led to precipitation of epsomite and probably aplowite on the top layer of substrate, similar to what is observed in field investigations. After 4 weeks, the first iron and manganese bearing secondary minerals became visible. Soil water samples were used to monitor the behaviour of metals within the lysimeter. Saturation indices (SI) for different secondary minerals were calculated with PHREEQC. The SI of goethite showed oversaturation with respect to the soil solution. SEM-EDX analyses and IR spectroscopy confirmed the formation of goethite. Geochemical data revealed that goethite formation was mainly dominated by Eh/pH processes and that heavy metals, e.g. Zn and U, could be enriched in this phase. Although Eh/pH data does not support formation of manganese minerals, Mn(II)-oxidizing bacteria (MOB) could be isolated from field

  16. Microtextured Silicon Surfaces for Detectors, Sensors & Photovoltaics

    SciTech Connect

    Carey, JE; Mazur, E

    2005-05-19

    With support from this award we studied a novel silicon microtexturing process and its application in silicon-based infrared photodetectors. By irradiating the surface of a silicon wafer with intense femtosecond laser pulses in the presence of certain gases or liquids, the originally shiny, flat surface is transformed into a dark array of microstructures. The resulting microtextured surface has near-unity absorption from near-ultraviolet to infrared wavelengths well below the band gap. The high, broad absorption of microtextured silicon could enable the production of silicon-based photodiodes for use as inexpensive, room-temperature multi-spectral photodetectors. Such detectors would find use in numerous applications including environmental sensors, solar energy, and infrared imaging. The goals of this study were to learn about microtextured surfaces and then develop and test prototype silicon detectors for the visible and infrared. We were extremely successful in achieving our goals. During the first two years of this award, we learned a great deal about how microtextured surfaces form and what leads to their remarkable optical properties. We used this knowledge to build prototype detectors with high sensitivity in both the visible and in the near-infrared. We obtained room-temperature responsivities as high as 100 A/W at 1064 nm, two orders of magnitude higher than standard silicon photodiodes. For wavelengths below the band gap, we obtained responsivities as high as 50 mA/W at 1330 nm and 35 mA/W at 1550 nm, close to the responsivity of InGaAs photodiodes and five orders of magnitude higher than silicon devices in this wavelength region.

  17. TEM observation of bacteria-induced plagioclase dissolution and secondary mineral formation

    NASA Astrophysics Data System (ADS)

    Tamura, T.; Kyono, A.; Nishimiya, Y.

    2015-12-01

    Silicate minerals are the most common minerals in the earth's crust. Bacteria are also distributed throughout the earth's surface environment. The silicate minerals are known to be dissolved by organic acids and polysaccharides known as bacteria metabolites. The metabolic activity of bacteria therefore plays an important role in the interaction between dissolution of the silicate minerals and formation of secondary minerals. However, little is known about the secondary mineral formation process associated with the bacterial metabolism. To clarify the bacterial effect on the mineral dissolution and the secondary mineral formation, we closely investigated the effect of bacterial activity on surface texture modification and chemical composition changes of plagioclase which is the most abundant silicate mineral in the earth's crust. The bacteria were isolated from soil and then added in a suitable medium with several plagioclase fragments (Ab100% and An100%). It was incubated for 10 days. Al and Si concentrations in the medium were measured by ICP-AES to monitor the dissolution of the plagioclase. Secondary mineral formation during the incubation was observed by TEM, EDS and SAED methods. The authors will give the experiment results and discuss the effect of bacterial activity on the plagioclase dissolution and the secondary mineral formation in detail.

  18. Nuclear Melt Glass Dissolution and Secondary Mineral Precipitation at 40 to 200C

    SciTech Connect

    Zavarin, M; Roberts, S; Viani, B; Pawloski, G; Rose, T

    2004-06-14

    Most long-lived radionuclides associated with an underground nuclear test are initially incorporated into melt glass and become part of the hydrologic source term (HST) only upon their release via glass dissolution (Pawloski et al., 2001). As the melt glass dissolves, secondary minerals precipitate. The types of secondary minerals that precipitate influence the water chemistry in and around the melt glass. The secondary minerals also provide a sorption sink to the released radionuclides. The changing water chemistry affects the rate of glass dissolution; it also affects the sorption behavior of the released radionuclides. This complex nature of glass dissolution and its important role in defining the HST requires a thorough understanding of glass dissolution and secondary mineral precipitation. The identity of secondary minerals formed at temperatures from 40 to 200 C are evaluated in this report to assist in that understanding.

  19. Secondary Minerals in Nakhla: A 3D Reconstruction of Alteration Sequences

    NASA Astrophysics Data System (ADS)

    Krzesinska, A. M.; Michalski, J. R.; Smith, C. L.; Schofield, P. F.

    2016-08-01

    Realtionship of secondary to primary minerals and fractures in Nakhla helps to gain insight into their formation and replacement history, and subsequently nature of aqueous events in the martian subsurface, and their implications for habitability.

  20. Clinical Use of Laser-Microtextured Abutments: A Case Series.

    PubMed

    Shapoff, Cary A; Babushkin, Jeffrey A; Wohl, David J

    2016-01-01

    This article discusses the clinical use of laser-microtextured abutments on dental implant restorations. Four cases are presented, each using one of the four commercially available laser-microtextured abutment styles. Numerous preclinical and clinical studies have shown the positive effects of laser microtexturing on the implant platform in limiting crestal bone loss and benefiting soft tissue stability. Other histologic studies of laser microtexturing on the implant abutment have demonstrated the ability of this specific feature to block epithelial downgrowth and provide a functional connective tissue attachment to the abutment surface. Other abutment designs, styles, and materials have only demonstrated a soft tissue seal with epithelial adhesion and a circular ring of connective tissue fibers around the abutment without direct contact. This article presents clinical and radiographic case examples from a private practice perspective on the longterm successful use of microtextured abutments with respect to crestal bone levels, exceptional soft tissue health, and stability with minimal sulcular depth. PMID:27560683

  1. The Chronology of Asteroid Accretion, Differentiation, and Secondary Mineralization

    NASA Technical Reports Server (NTRS)

    Nyquist, L. E.; Kleine, T.; Shih, C.-Y.; Reese, Y. D.

    2008-01-01

    ) and a Pb-207/Pb-206 age of 4558.6 Ma for the LEW86010 angrite. However. the (Mn-53/Mn-55)(sub I) and Pb-207/Pb-206 ages of "intermediate" age D'Orbigny-clan angrites and Asuka 881394 are inconsistent with radioactive decay from CAI values with a Mn-55 half-life of 3.7+/-0.4 Ma. in spite of consistency between (Mn-53/Mn-55)(sub I) and (Al-26/Al-27)(sub I). Nevertheless, it appears that the Mn-Cr method with I(Mn)(sub CAI) = 9.1+/-1.7 x 10(exp -6) can be used to date primary igneous events and also secondary mineralization on asteroid parent bodies. We summarize ages thus determined for igneous events on differentiated asteroids and for carbonate and fayalite formation on carbonaceous asteroids.

  2. Alkali feldspar dissolution and secondary mineral precipitation in batch systems: 3. Saturation states of product minerals and reaction paths

    NASA Astrophysics Data System (ADS)

    Zhu, Chen; Lu, Peng

    2009-06-01

    In order to evaluate the complex interplay between dissolution and precipitation reaction kinetics, we examined the hypothesis of partial equilibria between secondary mineral products and aqueous solutions in feldspar-water systems. Speciation and solubility geochemical modeling was used to compute the saturation indices (SI) for product minerals in batch feldspar dissolution experiments at elevated temperatures and pressures and to trace the reaction paths on activity-activity diagrams. The modeling results demonstrated: (1) the experimental aqueous solutions were supersaturated with respect to product minerals for almost the entire duration of the experiments; (2) the aqueous solution chemistry did not evolve along the phase boundaries but crossed the phase boundaries at oblique angles; and (3) the earlier precipitated product minerals did not dissolve but continued to precipitate even after the solution chemistry had evolved into the stability fields of minerals lower in the paragenesis sequence. These three lines of evidence signify that product mineral precipitation is a slow kinetic process and partial equilibria between aqueous solution and product minerals were not held. In contrast, the experimental evidences are consistent with the hypothesis of strong coupling of mineral dissolution/precipitation kinetics [e.g., Zhu C., Blum A. E. and Veblen D. R. (2004a) Feldspar dissolution rates and clay precipitation in the Navajo aquifer at Black Mesa, Arizona, USA. In Water-Rock Interaction (eds. R. B. Wanty and R. R. I. Seal). A.A. Balkema, Saratoga Springs, New York. pp. 895-899]. In all batch experiments examined, the time of congruent feldspar dissolution was short and supersaturation with respect to the product minerals was reached within a short period of time. The experimental system progressed from a dissolution driven regime to a precipitation limited regime in a short order. The results of this study suggest a complex feedback between dissolution and

  3. Aortoiliac thrombus secondary to a mineralized arteriosclerotic lesion.

    PubMed

    Drost, W T; Bahr, R J; Henry, G A; Campbell, G A

    1999-01-01

    A 12-year-old, neutered female, Siberian Husky dog presented with a hind limb weakness of one month duration. To facilitate making a diagnosis multiple imaging modalities were performed. These modalities included radiography, ultrasonography, magnetic resonance imaging (MRI), magnetic resonance angiography (MRA) and selective angiography of the abdominal aorta. In this dog, the MRI/MRA studies provided the first documentation of the external iliac thrombi and the collateral circulation via the lumbar arteries. At necropsy, an aortoiliac thrombus caused by a mineralized arteriosclerotic plaque was noted.

  4. Method of making a coating of a microtextured surface

    DOEpatents

    Affinito, John D [Tucson, AZ; Graff, Gordon L [West Richland, WA; Martin, Peter M [Kennewick, WA; Gross, Mark E [Pasco, WA; Burrows, Paul E [Kennewick, WA; Sapochak, Linda S [Henderson, NV

    2004-11-02

    A method for conformally coating a microtextured surface. The method includes flash evaporating a polymer precursor forming an evaporate, passing the evaporate to a glow discharge electrode creating a glow discharge polymer precursor plasma from the evaporate, cryocondensing the glow discharge polymer precursor plasma on the microtextured surface and crosslinking the glow discharge polymer precursor plasma thereon, wherein the crosslinking resulting from radicals created in the glow discharge polymer precursor plasma.

  5. Microbial Composition in Decomposing Pine Litter Shifts in Response to Common Soil Secondary Minerals

    NASA Astrophysics Data System (ADS)

    Welty-Bernard, A. T.; Heckman, K.; Vazquez, A.; Rasmussen, C.; Chorover, J.; Schwartz, E.

    2011-12-01

    A range of environmental and biotic factors have been identified that drive microbial community structure in soils - carbon substrates, redox conditions, mineral nutrients, salinity, pH, and species interactions. However, soil mineralogy has been largely ignored as a candidate in spite of recent studies that indicate that minerals have a substantial impact on soil organic matter stores and subsequent fluxes from soils. Given that secondary minerals and organic colloids govern a soil's biogeochemical activity due to surface area and electromagnetic charge, we propose that secondary minerals are a strong determinant of the communities that are responsible for process rates. To test this, we created three microcosms to study communities during decomposition using pine forest litter mixed with two common secondary minerals in soils (goethite and gibbsite) and with quartz as a control. Changes in bacterial and fungal communities were tracked over the 154-day incubation by pyrosequencing fragments of the bacterial 16S and fungal 18S rRNA genes. Ordination using nonmetric multidimensional scaling showed that bacterial communities separated on the basis of minerals. Overall, a single generalist - identified as an Acidobacteriaceae isolate - dominated all treatments over the course of the experiment, representing roughly 25% of all communities. Fungal communities discriminated between the quartz control alone and mineral treatments as a whole. Again, several generalists dominated the community. Coniochaeta ligniaria dominated communities with abundances ranging from 29 to 40%. The general stability of generalist populations may explain the similarities between treatment respiration rates. Variation between molecular fingerprints, then, were largely a function of unique minor members with abundances ranging from 0.01 to 8%. Carbon availability did not surface as a possible mechanism responsible for shifts in fingerprints due to the relatively large mass of needles in the

  6. Mineral phases and metals in baghouse dust from secondary aluminum production

    EPA Science Inventory

    Baghouse dust (BHD) is a solid waste generated by air pollution control systems during secondary aluminum processing (SAP). Management and disposal of BHD can be challenging in the U.S. and elsewhere. In this study, the mineral phases, metal content and metal leachability of 78...

  7. Weathering features and secondary minerals in Antarctic Shergottites ALHA77005 and LEW88516

    NASA Technical Reports Server (NTRS)

    Wentworth, Susan J.; Gooding, James L.

    1993-01-01

    Previous work has shown that all three sub-groups of the shergottite, nakhlite, and chassignite (SNC) clan of meteorites contain aqueous precipitates of probable pre-terrestrial origin. In the context of secondary minerals, the most thoroughly studied shergottite has been Elephant Moraine, Antarctica A79001 (EETA79001). The recognition of LEW88516 as the latest SNC specimen, and its close similarity with ALHA77005, invite a comparative study of the latter two meteorites, and with EETA79001, from the perspective of aqueous alteration. The fusion crusts of the two meteorites are quite similar except that ALHA77005 is more vesicular (possibly indicating a higher indigenous volatile content). Secondary aluminosilicates (and salts on LEW88516) of definite Antarctic origin partially fill vesicles and fractures on both fusion crusts. Interior samples of the two meteorites are grossly similar in that traces of secondary minerals are present in both.

  8. Radionuclide Incorporation in Secondary Crystalline Minerals from Chemical Weathering of Waste Glasses

    SciTech Connect

    Mattigod, Shas V.; Serne, R JEFFREY.; McGrail, B PETER.; Legore, Virginia L.

    2002-09-01

    Data from corrosion and radionuclide sequestration studies on two waste glasses indicated chemical weathering resulted in the formation of zeolite minerals such as herschelite and analcime. We also found that these minerals incorporated {approx}8 - 22%, {approx}1- 13% and {approx}8 - 25% of spiked 125-I, 99-Tc, and 75-Se respectively. Increasing concentrations of radionuclides in spike solution resulted in higher degree of sequestration as observed by significantly higher proportion of stable isotopes ({approx}70 - 95% I, {approx}58 - 100% Re, and {approx}100% Se) in secondary minerals. The radionuclide incorporation mechanisms for these minerals appear to be mainly isomorphic substitution of Se and Re in tetrahedral sites and iodide substitution for framework oxygen.

  9. Minerals

    MedlinePlus

    Minerals are important for your body to stay healthy. Your body uses minerals for many different jobs, including building bones, making ... regulating your heartbeat. There are two kinds of minerals: macrominerals and trace minerals. Macrominerals are minerals your ...

  10. Secondary mineralization pathways induced by dissimilatory iron reduction of ferrihydrite under advective flow

    NASA Astrophysics Data System (ADS)

    Hansel, Colleen M.; Benner, Shawn G.; Neiss, Jim; Dohnalkova, Alice; Kukkadapu, Ravi K.; Fendorf, Scott

    2003-08-01

    Iron (hydr)oxides not only serve as potent sorbents and repositories for nutrients and contaminants but also provide a terminal electron acceptor for microbial respiration. The microbial reduction of Fe (hydr)oxides and the subsequent secondary solid-phase transformations will, therefore, have a profound influence on the biogeochemical cycling of Fe as well as associated metals. Here we elucidate the pathways and mechanisms of secondary mineralization during dissimilatory iron reduction by a common iron-reducing bacterium, Shewanella putrefaciens (strain CN32), of 2-line ferrihydrite under advective flow conditions. Secondary mineralization of ferrihydrite occurs via a coupled, biotic-abiotic pathway primarily resulting in the production of magnetite and goethite with minor amounts of green rust. Operating mineralization pathways are driven by competing abiotic reactions of bacterially generated ferrous iron with the ferrihydrite surface. Subsequent to the initial sorption of ferrous iron on ferrihydrite, goethite (via dissolution/reprecipitation) and/or magnetite (via solid-state conversion) precipitation ensues resulting in the spatial coupling of both goethite and magnetite with the ferrihydrite surface. The distribution of goethite and magnetite within the column is dictated, in large part, by flow-induced ferrous Fe profiles. While goethite precipitation occurs over a large Fe(II) concentration range, magnetite accumulation is only observed at concentrations exceeding 0.3 mmol/L (equivalent to 0.5 mmol Fe[II]/g ferrihydrite) following 16 d of reaction. Consequently, transport-regulated ferrous Fe profiles result in a progression of magnetite levels downgradient within the column. Declining microbial reduction over time results in lower Fe(II) concentrations and a subsequent shift in magnetite precipitation mechanisms from nucleation to crystal growth. While the initial precipitation rate of goethite exceeds that of magnetite, continued growth is inhibited by

  11. Reduction of jarosite by Shewanella oneidensis MR-1 and secondary mineralization

    NASA Astrophysics Data System (ADS)

    Bingjie, Ouyang; Xiancai, Lu; Huan, Liu; Juan, Li; Tingting, Zhu; Xiangyu, Zhu; Jianjun, Lu; Rucheng, Wang

    2014-01-01

    Jarosite is a common mineral in a variety of environments formed by the oxidation of iron sulfide normally accompanying with the generation of acid mine drainage (AMD) in mining areas or acid rock drainages (ARD) in many localities. Decomposition of jarosite by dissimilatory iron reducing bacteria (DIRB) influences the mobility of many heavy metals generally accommodated in natural jarosite. This study examined the anaerobic reduction of synthesized jarosite by Shewanella oneidensis strain MR-1, a typical facultative bacteria. The release of ferrous and ferric ion, as well as sulfate and potassium, in the inoculated experimental group lasting 80 days is much higher than that in abiotic control groups. The detection of bicarbonate and acetate in experimental solution further confirms the mechanism of microbial reduction of jarosite, in which lactate acts as the electron donor. The produced ferrous iron stimulates the subsequent secondary mineralization, leading to precipitation and transformation of various iron-containing minerals. Green rust and goethite are the intermediate minerals of the microbial reduction process under anoxic conditions, and the end products include magnetite and siderite. In aerobic environments, goethite, magnetite and siderite were also detected, but the contents were relatively lower. While in abiotic experiments, only goethite has been detected as a product. Thus, the microbial reduction and subsequent mineral transformation can remarkably influence the geochemical cycling of iron and sulfur in supergene environments, as well as the mobility of heavy metals commonly accommodated in jarosite.

  12. Mineral Dissolution and Secondary Precipitation on Quartz Sand in Simulated Hanford Tank Solutions Affecting Subsurface Porosity

    SciTech Connect

    Wang, Guohui; Um, Wooyong

    2012-11-23

    Highly alkaline nuclear waste solutions have been released from underground nuclear waste storage tanks and pipelines into the vadose zone at the U.S. Department of Energy’s Hanford Site in Washington, causing mineral dissolution and re-precipitation upon contact with subsurface sediments. High pH caustic NaNO3 solutions with and without dissolved Al were reacted with quartz sand through flow-through columns stepwise at 45, 51, and 89°C to simulate possible reactions between leaked nuclear waste solution and primary subsurface mineral. Upon reaction, Si was released from the dissolution of quartz sand, and nitrate-cancrinite [Na8Si6Al6O24(NO3)2] precipitated on the quartz surface as a secondary mineral phase. Both steady-state dissolution and precipitation kinetics were quantified, and quartz dissolution apparent activation energy was determined. Mineral alteration through dissolution and precipitation processes results in pore volume and structure changes in the subsurface porous media. In this study, the column porosity increased up to 40.3% in the pure dissolution column when no dissolved Al was present in the leachate, whereas up to a 26.5% porosity decrease was found in columns where both dissolution and precipitation were observed because of the presence of Al in the input solution. The porosity change was also confirmed by calculation using the dissolution and precipitation rates and mineral volume changes.

  13. Dynamics of Spreading on Micro-Textured Surfaces

    NASA Astrophysics Data System (ADS)

    Mohammad Karim, Alireza; Rothstein, Jonathan; Kavehpour, Pirouz

    2015-11-01

    Ultrahydrophobic surfaces, due to their large water-repellency characteristic, have a vast variety of applications in technology and nature, such as de-icing of airplane wings, efficiency increase of power plants, and efficiency of pesticides on plants, etc. The significance of ultrahydrophobic surfaces requires enhancing the knowledge on the spreading dynamics on such surfaces. The best way to produce an ultrahydrophobic surface is by patterning of smooth hydrophobic surfaces with micron sized posts. In this research, the micro-textured surfaces have been fabricated by patterning several different sizes of micro-textured posts on Teflon plates. The experimental study has been performed using forced spreading with Tensiometer to obtain the dependencw of dynamic contact angle to the contact line velocity to describe the spreading dynamics of Newtonian liquids on the micro-textured surfaces. The effect of the geometrical descriptions of the micro-posts along with the physical properties of liquids on the spreading dynamics on micro-textured Teflon plates have been also studied.

  14. Lithologic Control on Secondary Clay Mineral Formation in the Valles Caldera, New Mexico

    NASA Astrophysics Data System (ADS)

    Caylor, E.; Rasmussen, C.; Dhakal, P.

    2015-12-01

    Understanding the transformation of rock to soil is central to landscape evolution and ecosystem function. The objective of this study was to examine controls on secondary mineral formation in a forested catchment in the Catalina-Jemez CZO. We hypothesized landscape position controls the type of secondary minerals formed in that well-drained hillslopes favor Si-poor secondary phases such as kaolinite, whereas poorly drained portions of the landscape that collect solutes from surrounding areas favor formation of Si-rich secondary phases such as smectite. The study focused on a catchment in Valles Caldera in northern New Mexico where soils are derived from a mix of rhyolitic volcanic material, vegetation includes a mixed conifer forest, and climate is characterized by a mean annual precipitation of ~800 mm yr-1 and mean annual temperature of 4.5°C. Soils were collected at the soil-saprolite boundary from three landscape positions, classified as well drained hillslope, poorly drained convergent area, and poorly drained hill slope. Clay fractions were isolated and analyzed using a combination of quantitative and qualitative x-ray diffraction (XRD) analyses and thermal analysis. Quantitative XRD of random powder mounts indicated the presence of both primary phases such as quartz, and alkali and plagioclase feldspars, and secondary phases that include illite, Fe-oxyhydroxides including both goethite and hematite, kaolinite, and smectite. The clay fractions were dominated by smectite ranging from 36-42%, illite ranging from 21-35%, and kaolinite ranging from 1-8%. Qualitative XRD of oriented mounts confirmed the presence of smectite in all samples, with varying degrees of interlayering and interstratification. In contrast to our hypothesis, results indicated that secondary mineral assemblage was not strongly controlled by landscape position, but rather varied with underlying variation in lithology. The catchment is underlain by a combination of porphorytic rhyolite and

  15. Inhibition Effect of Secondary Phosphate Mineral Precipitation on Uranium Release from Contaminated Sediments

    SciTech Connect

    Shi, Zhenqing; Liu, Chongxuan; Zachara, John M.; Wang, Zheming; Deng, Baolin

    2009-11-01

    The inhibitory effect of phosphate mineral precipitation on uranium release was evaluated using a U(VI)-contaminated sediment collected from the US Department of Energy (DOE) Hanford site. The sediment contained U(VI) that was associated with diffusion-limited intragrain regions within its mm-size granitic lithic fragments. The sediment was first treated to promote phosphate mineral precipitation in batch suspensions spiked with 1 and 50 mM aqueous phosphate, and calcium in a stoichiometric ratio of mineral hydroxyapatite. The phosphate-treated sediment was then leached to solubilize contaminant U(VI) in a column system using a synthetic groundwater that contained chemical components representative of Hanford groundwater. Phosphate treatment significantly decreased the extent of U(VI) release from the sediment. Within the experimental duration of about 200 pore volumes, the effluent U(VI) concentrations were consistently lower by over one and two orders of magnitude after the sediment was treated with 1 and 50 mM of phosphate, respectively. Measurements of solid phase U(VI) using various spectroscopes and chemical extraction of the sediment collectively indicated that the inhibition of U(VI) release from the sediment was caused by: 1) U(VI) adsorption to the secondary phosphate precipitates and 2) the transformation of initially present U(VI) mineral phases to less soluble forms.

  16. Bone mineral density evaluation among patients with neuromuscular scoliosis secondary to cerebral palsy☆

    PubMed Central

    Rezende, Rodrigo; Cardoso, Igor Machado; Leonel, Rayana Bomfim; Perim, Larissa Grobério Lopes; Oliveira, Tarcísio Guimarães Silva; Jacob Júnior, Charbel; Júnior, José Lucas Batista; Lourenço, Rafael Burgomeister

    2014-01-01

    Objective To evaluate bone mineral density among patients with neuromuscular scoliosis secondary to quadriplegic cerebral palsy. Methods This was a descriptive prospective study in which both bone densitometric and anthropometric data were evaluated. The inclusion criteria used were that the patients should present quadriplegic cerebral palsy, be confined to a wheelchair, be between 10 and 20 years of age and present neuromuscular scoliosis. Results We evaluated 31 patients (20 females) with a mean age of 14.2 years. Their mean biceps circumference, calf circumference and body mass index were 19.4 cm, 18.6 cm and 16.9 kg/m2, respectively. The mean standard deviation from bone densitometry was −3.2 (z-score), which characterizes osteoporosis. Conclusion There is high incidence of osteoporosis in patients with neuromuscular scoliosis secondary to quadriplegic cerebral palsy. PMID:26229882

  17. Control of mineral scale deposition in cooling systems using secondary-treated municipal wastewater.

    PubMed

    Li, Heng; Hsieh, Ming-Kai; Chien, Shih-Hsiang; Monnell, Jason D; Dzombak, David A; Vidic, Radisav D

    2011-01-01

    Secondary-treated municipal wastewater (MWW) is a promising alternative to freshwater as power plant cooling system makeup water, especially in arid regions. A prominent challenge for the successful use of MWW for cooling is potentially severe mineral deposition (scaling) on pipe surfaces. In this study, theoretical, laboratory, and field work was conducted to evaluate the mineral deposition potential of MWW and its deposition control strategies under conditions relevant to power plant cooling systems. Polymaleic acid (PMA) was found to effectively reduce scale formation when the makeup water was concentrated four times in a recirculating cooling system. It was the most effective deposition inhibitor of those studied when applied at 10 mg/L dosing level in a synthetic MWW. However, the deposition inhibition by PMA was compromised by free chlorine added for biogrowth control. Ammonia present in the wastewater suppressed the reaction of the free chlorine with PMA through the formation of chloramines. Monochloramine, an alternative to free chlorine, was found to be less reactive with PMA than free chlorine. In pilot tests, scaling control was more challenging due to the occurrence of biofouling even with effective control of suspended bacteria. Phosphorous-based corrosion inhibitors are not appropriate due to their significant loss through precipitation reactions with calcium. Chemical equilibrium modeling helped with interpretation of mineral precipitation behavior but must be used with caution for recirculating cooling systems, especially with use of MWW, where kinetic limitations and complex water chemistries often prevail. PMID:20851443

  18. Alteration of bentonite by hyperalkaline fluids: A review of the role of secondary minerals

    NASA Astrophysics Data System (ADS)

    Savage, David; Walker, Colin; Arthur, Randy; Rochelle, Chris; Oda, Chie; Takase, Hiro

    Data concerning potential solid products of the interaction of cement pore fluids with bentonite have been reviewed with respect to accurate prediction of bentonite alteration in the long-term. Calcium (aluminium) silicate hydrates (C(A)SH), zeolites, feldspars, hydroxides, carbonates, polymorphs of silica, and some sheet silicates (all of varying degrees of crystallinity) are potential products of cement-bentonite interaction. Evidence from natural systems and laboratory studies suggests that most, or all of these phases, may precipitate on timescales of interest to safety assessment of the geological disposal of radioactive wastes. These data indicate that growth kinetics of secondary minerals is equally as important as thermodynamic stability in controlling occurrence. C(A)SH show variable Ca/Si ratio and Al contents. At high pH (>11), the growth of C(A)SH minerals provides a means by which OH - ions from cement pore fluids may be titrated. Although thermodynamic data exist for a number of naturally-occurring crystalline C(A)SH minerals, they are of doubtful quality and should be applied with caution in predictive modelling. Zeolites are likely to form at lower pH than for C(A)SH, with the Si/Al ratio of the zeolite decreasing with increasing pH of the fluid. Zeolite stability is also strongly dependent upon silica activity in the fluid phase. Although silica activity in bentonite pore fluids will be spatially (and temporally) variable as hyperalkaline alteration proceeds, it is likely that minerals which could form would be those stable in quartz-saturated or supersaturated fluids. Currently available thermodynamic data for zeolites tend to overestimate their stability, leading to inaccurate predictions of their occurrence. Notwithstanding this uncertainty, it is considered that the following secondary minerals are the most likely to form in low temperature cement-bentonite systems: calcite, dolomite, chalcedony, C(A)SH of variable Ca/Si ratio, K

  19. Hydrothermal alteration in Oregon's Newberry Volcano No. 2: fluid chemistry and secondary-mineral distribution

    SciTech Connect

    Keith, T.E.C.; Mariner, R.H.; Bargar, K.E.; Evans, W.C.; Presser, T.S.

    1984-04-01

    Newberry 2 was drilled in the caldera floor of Newberry Volcano, Oregon, by the US Geological Survey during 1979-81. The maximum temperature measured was 265C at the bottom of the hole, 932 m below the surface. Rocks recovered fr9om the drill hole are divided into three intervals on the basis of hydrothermal alteration and mineral deposition: (1) 0-290 m consists of unaltered, largely glassy volcanic material, with present temperatures ranging from 20 to 40C; (2) 290-700 m consists of permeable tuff layers, tuff breccia units, and brecciated and fractured rhyodacitic to dacitic lava flows, with temperatures ranging from 40 to 100C; (3) 700-932 m consists of impermeable andesitic to basaltic lava flows that generally show little effect of alteration, interlayered with permeable hydrothermally altered flow breccia, with temperatures gradually increasing from 100 at 700 m to 265C at 932 m. Hydrothermal alteration throughout the system is controlled by rock permeability, temperature, composition of geothermal fluids, and composition and crystallinity of host rocks. Rock alteration consists mainly of replacement of glass by clay minerals and, locally, zeolites, partial replacement of plagioclase phenocrysts by calcite +/- epidote +/- illite, and whole-rock leaching adjacent to fluids channels. Open-space deposition of hydrothermal minerals in fractures, vesicles, and interbreccia pore space is far more abundant than replacement. A cooling shallow convection system in the upper 700 m is indicated by the occurrence of hydrothermal minerals that were deposited in a slightly higher temperature environment than presently exists. Below 700 m, the heat flow is conductive, and fluid flow is controlled by horizontal lava flows. Homogenization temperatures of secondary quartz fluid inclusions were as high as 370C.

  20. Lava cave microbial communities within mats and secondary mineral deposits: implications for life detection on other planets.

    PubMed

    Northup, D E; Melim, L A; Spilde, M N; Hathaway, J J M; Garcia, M G; Moya, M; Stone, F D; Boston, P J; Dapkevicius, M L N E; Riquelme, C

    2011-09-01

    Lava caves contain a wealth of yellow, white, pink, tan, and gold-colored microbial mats; but in addition to these clearly biological mats, there are many secondary mineral deposits that are nonbiological in appearance. Secondary mineral deposits examined include an amorphous copper-silicate deposit (Hawai'i) that is blue-green in color and contains reticulated and fuzzy filament morphologies. In the Azores, lava tubes contain iron-oxide formations, a soft ooze-like coating, and pink hexagons on basaltic glass, while gold-colored deposits are found in lava caves in New Mexico and Hawai'i. A combination of scanning electron microscopy (SEM) and molecular techniques was used to analyze these communities. Molecular analyses of the microbial mats and secondary mineral deposits revealed a community that contains 14 phyla of bacteria across three locations: the Azores, New Mexico, and Hawai'i. Similarities exist between bacterial phyla found in microbial mats and secondary minerals, but marked differences also occur, such as the lack of Actinobacteria in two-thirds of the secondary mineral deposits. The discovery that such deposits contain abundant life can help guide our detection of life on extraterrestrial bodies.

  1. Lava Cave Microbial Communities Within Mats and Secondary Mineral Deposits: Implications for Life Detection on Other Planets

    PubMed Central

    Melim, L.A.; Spilde, M.N.; Hathaway, J.J.M.; Garcia, M.G.; Moya, M.; Stone, F.D.; Boston, P.J.; Dapkevicius, M.L.N.E.; Riquelme, C.

    2011-01-01

    Abstract Lava caves contain a wealth of yellow, white, pink, tan, and gold-colored microbial mats; but in addition to these clearly biological mats, there are many secondary mineral deposits that are nonbiological in appearance. Secondary mineral deposits examined include an amorphous copper-silicate deposit (Hawai‘i) that is blue-green in color and contains reticulated and fuzzy filament morphologies. In the Azores, lava tubes contain iron-oxide formations, a soft ooze-like coating, and pink hexagons on basaltic glass, while gold-colored deposits are found in lava caves in New Mexico and Hawai‘i. A combination of scanning electron microscopy (SEM) and molecular techniques was used to analyze these communities. Molecular analyses of the microbial mats and secondary mineral deposits revealed a community that contains 14 phyla of bacteria across three locations: the Azores, New Mexico, and Hawai‘i. Similarities exist between bacterial phyla found in microbial mats and secondary minerals, but marked differences also occur, such as the lack of Actinobacteria in two-thirds of the secondary mineral deposits. The discovery that such deposits contain abundant life can help guide our detection of life on extraterrestrial bodies. Key Words: Biosignatures—Astrobiology—Bacteria—Caves—Life detection—Microbial mats. Astrobiology 11, 601–618. PMID:21879833

  2. Secondary Sulfate Mineralization and Basaltic Chemistry of Craters of the Moon National Monument, Idaho: Potential Martian Analog

    SciTech Connect

    C. Doc Richardson; Nancy W. Hinman; Lindsay J. McHenry; J. Michelle Kotler; Jill R. Scott

    2012-05-01

    Secondary deposits associated with the basaltic caves of Craters of the Moon National Monument (COM) in southern Idaho were examined using X-ray powder diffraction, X-ray fluorescence spectrometry, Fourier transform infrared spectrometry, and Fourier transform ion cyclotron resonance mass spectrometry (FTICR-MS). The secondary mineral assemblages are dominated by Na-sulfate minerals (thenardite, mirabilite) with a small fraction of the deposits containing minor concentrations of Na-carbonate minerals. The assemblages are found as white, efflorescent deposits in small cavities along the cave walls and ceilings and as localized mounds on the cave floors. Formation of the deposits is likely due to direct and indirect physiochemical leaching of meteoritic water through the overlying basalts. Whole rock data from the overlying basaltic flows are characterized by their extremely high iron concentrations, making them good analogs for martian basalts. Understanding the physiochemical pathways leading to secondary mineralization at COM is also important because lava tubes and basaltic caves are present on Mars. The ability of FTICR-MS to consistently and accurately identify mineral species within these heterogeneous mineral assemblages proves its validity as a valuable technique for the direct fingerprinting of mineral species by deductive reasoning or by comparison with reference spectra.

  3. Secondary Mineralization of Components in CV3 Chondrites: Nebular and Asteroidal Models

    NASA Astrophysics Data System (ADS)

    Scott, E. R. D.; Krot, A. N.; Zolensky, M. E.

    1995-09-01

    Our review of mineralogical variations among CV3 chondrites suggests that all components, chondrules, matrices, and CAIs, were affected by various degrees of secondary mineralization. Chondrules and CAIs are rimmed with fayalitic olivine [1, 2]; metal in all components is oxidized and sulfidized to magnetite, Ni-rich metal and sulfides [3]; silicates in all components are aqueously altered to phyllosilicates [4]; and nepheline, sodalite, wollastonite, and hedenbergite replace primary minerals in CAIs [5]. In those CV3s with altered CAIs, nepheline etc. are also present in chondrule mesostases [6] and in matrices [7]. Correlated occurrences of secondary minerals indicate that they have related origins. CV3 chondrites can be divided into three kinds according to their secondary features. Reduced CV3s (e.g., Efremovka) lack magnetite [8] and show minimal secondary features. Oxidized CV3s [8] generally show all features: those like Mokoia contain minor fayalitic rims, nepheline, etc, whereas those like Allende lack phyllosilicates but contain well developed fayalite rims and abundant nepheline, etc. Allende-like CV3 chondrites also contain abundant plate-like matrix olivine (Fa(sub)45-55). Similarities in chemistry and O isotopic composition and petrographic observations suggest that fayalitic rims and plate-like matrix olivine have related origins [1, 9]. The presence of secondary minerals in all components implies that alteration postdated component formation. The absence of secondary minerals in reduced CV3s indicates that CV3 oxidized formed from CV3 reduced-like material. Oxidized and reduced materials coexist in some breccias indicating a common parent asteroid. Nebular origins are widely accepted for most secondary features. To form fayalitic rims and matrix , Palme and colleagues [10, 11] suggest that chondritic components were briefly exposed to a hot (>1500 K), highly oxidizing nebula with H2O/H2 to about 1. Such an environment could have resulted from

  4. Reactivity of Primary Soil Minerals and Secondary Precipitates Beneath Leaking Hanford Waste Tanks

    SciTech Connect

    Nagy, Kathryn L.; Sturchio, Neil C.

    2003-06-01

    This project, renewal of a previous EMSP project of the same title, is in its first year of funding at the University of Illinois at Chicago. The purpose is to continue investigating rates and mechanisms of reactions between primary sediment minerals found in the Hanford subsurface and leaked waste tank solutions. The goals are to understand processes that result in (1) changes in porosity and permeability of the sediment and resultant changes in flow paths of the contaminant plumes, (2) formation of secondary precipitates that can take up contaminants in their structures, and (3) release of mineral components that can drive redox reactions affecting dissolved contaminant mobility. A post-doctoral scientist, Dr. Sherry Samson, has been hired and two masters of science students are beginning to conduct experimental research. One research project that is underway is focused on measurement of the dissolution rates of plagioclase feldspar in high pH, high nitrate, high Al-bearing solutions characteristic of the BX tank farms. The first set of experiments is being conduced at room temperature. Subsequent experiments will examine the role of temperature because tank solutions in many cases were near boiling when leakage is thought to have occurred and temperature gradients have been observed beneath the SX and BX tank farms. The dissolution experiments are being conducted in stirred-flow kinetic reactors using powdered labradorite feldspar from Pueblo Park, New Mexico.

  5. Minerals salt composition and secondary metabolites of Euphorbia hirta Linn., an antihyperglycemic plant

    PubMed Central

    Yvette Fofie, N’Guessan Bra; Sanogo, Rokia; Coulibaly, Kiyinlma; Kone-Bamba, Diénéba

    2015-01-01

    Phytochemical study and research on acute toxicity were performed on the aerial parts (leaves and stems) of Euphorbia hirta Linn. The phytochemical screening and chromatography revealed the presence of saponin, sterol, terpene, alkaloids, polyphenols, tannins and flavonoids and especially mucilage. The evaluation of total polyphenols and total flavonoids gave 120.97 ± 7.07 gallic acid equivalents (GAE) mg/g (mg of GAE/g of extract) of dry extract and 41.4 ± 0.5 mg quercetin equivalent per gram (QE/g) (mg of QE/g of plant extract) of dry extract respectively. The physicochemical study revealed moisture content of 7.73% ± 0.00%, total ash 7.48% ± 0.03%. Sulfuric ash 9.05% ± 0.01%, hydrochloric acid insoluble ash of 0.8% ± 0.02%. The search for minerals salt revealed the presence of Cr, Zn, K, Ca and Mg having an important role in glucose metabolism. The acute toxicity study showed that the toxic dose may be above 3000 mg/kg. The results of these studies indicate that extracts from the leaves and stem of E. hirta Linn. contains trace elements and minerals salt and bioactive secondary metabolites which explain their therapeutic uses for treating diabetes mellitus. PMID:25598628

  6. Evidence for an unsaturated-zone origin of secondary minerals in Yucca Mountain, Nevada

    SciTech Connect

    Whelan, Joseph F.; Roedder, Edwin; Paces, James B.

    2001-04-29

    The unsaturated zone (UZ) in Miocene-age welded tuffs at Yucca Mountain, Nevada, is under consideration as a potential site for the construction of a high-level radioactive waste repository. Secondary calcite and silica minerals deposited on fractures and in cavities in the UZ tuffs are texturally, isotopically, and geochemically consistent with UZ deposition from meteoric water infiltrating at the surface and percolating through the UZ along fractures. Nonetheless, two-phase fluid inclusions with small and consistent vapor to liquid (V:L) ratios that yield consistent temperatures within samples and which range from about 35 to about 80 C between samples have led some to attribute these deposits to formation from upwelling hydrothermal waters. Geochronologic studies have shown that calcite and silica minerals began forming at least 10 Ma and continued to form into the Holocene. If their deposition were really from upwelling water flooding the UZ, it would draw into question the suitability of the site as a waste repository.

  7. Sorption and redox reactions of As(III) and As(V) within secondary mineral coatings on aquifer sediment grains.

    PubMed

    Singer, David M; Fox, Patricia M; Guo, Hua; Marcus, Matthew A; Davis, James A

    2013-10-15

    Important reactive phenomena that affect the transport and fate of many elements occur at the mineral-water interface (MWI), including sorption and redox reactions. Fundamental knowledge of these phenomena are often based on observations of ideal mineral-water systems, for example, studies of molecular scale reactions on single crystal faces or the surfaces of pure mineral powders. Much less is understood about MWI in natural environments, which typically have nanometer to micrometer scale secondary mineral coatings on the surfaces of primary mineral grains. We examined sediment grain coatings from a well-characterized field site to determine the causes of rate limitations for arsenic (As) sorption and redox processes within the coatings. Sediments were obtained from the USGS field research site on Cape Cod, MA, and exposed to synthetic contaminated groundwater solutions. Uptake of As(III) and As(V) into the coatings was studied with a combination of electron microscopy and synchrotron techniques to assess concentration gradients and reactive processes, including electron transfer reactions. Transmission electron microscopy (TEM) and X-ray microprobe (XMP) analyses indicated that As was primarily associated with micrometer- to submicrometer aggregates of Mn-bearing nanoparticulate goethite. As(III) oxidation by this phase was observed but limited by the extent of exposed surface area of the goethite grains to the exterior of the mineral coatings. Secondary mineral coatings are potentially both sinks and sources of contaminants depending on the history of a contaminated site, and may need to be included explicitly in reactive transport models.

  8. The role of reaction affinity and secondary minerals in regulating chemical weathering rates at the Santa Cruz Soil Chronosequence, California

    SciTech Connect

    Maher, K.; Steefel, C. I.; White, A.F.; Stonestrom, D.A.

    2009-02-25

    In order to explore the reasons for the apparent discrepancy between laboratory and field weathering rates and to determine the extent to which weathering rates are controlled by the approach to thermodynamic equilibrium, secondary mineral precipitation and flow rates, a multicomponent reactive transport model (CrunchFlow) was used to interpret soil profile development and mineral precipitation and dissolution rates at the 226 ka marine terrace chronosequence near Santa Cruz, CA. Aqueous compositions, fluid chemistry, transport, and mineral abundances are well characterized (White et al., 2008, GCA) and were used to constrain the reaction rates for the weathering and precipitating minerals in the reactive transport modeling. When primary mineral weathering rates are calculated with either of two experimentally determined rate constants, the nonlinear, parallel rate law formulation of Hellmann and Tisser and [2006] or the aluminum inhibition model proposed by Oelkers et al. [1994], modeling results are consistent with field-scale observations when independently constrained clay precipitation rates are accounted for. Experimental and field rates, therefore, can be reconciled at the Santa Cruz site. Observed maximum clay abundances in the argillic horizons occur at the depth and time where the reaction fronts of the primary minerals overlap. The modeling indicates that the argillic horizon at Santa Cruz can be explained almost entirely by weathering of primary minerals and in situ clay precipitation accompanied by undersaturation of kaolinite at the top of the profile. The rate constant for kaolinite precipitation was also determined based on model simulations of mineral abundances and dissolved Al, SiO{sub 2}(aq) and pH in pore waters. Changes in the rate of kaolinite precipitation or the flow rate do not affect the gradient of the primary mineral weathering profiles, but instead control the rate of propagation of the primary mineral weathering fronts and thus total

  9. Martian surface microtexture from orbital CRISM multi-angular observations: A new perspective for the characterization of the geological processes

    NASA Astrophysics Data System (ADS)

    Fernando, J.; Schmidt, F.; Douté, S.

    2016-09-01

    The surface of Mars has a high morphological and mineralogical diversity due to the intricacy of external, internal processes, and exchanges with the atmosphere, the hydrosphere and the cryosphere. In particular, liquid water played an important role in surface evolution. However, the origin, duration and intensity of those wet events have been highly debated, especially in the clay-bearing geological units. Similarly, questions still remain about magma crystallization and volatile quantity of the dominant basaltic crust. In this work, six sites having hydrated minerals, salts and basaltic signatures (i.e., Mawrth Vallis, Holden crater, Eberswalde crater, Capri mensa, Eridania basin, Terra Sirenum) are investigated in order to better characterize the geological processes responsible for their formation and evolution (e.g., fluvial, lacustrine, in situ weathering, evaporitic, volcanic and aeolian processes). For that purpose, we use orbital multi-angular measurements from the Compact Reconnaissance Imaging Spectrometer for Mars (CRISM) instrument on-board the Mars Reconnaissance Orbiter spacecraft to analyze the manner in which light is scattered by the surface materials (photometry) in the near-infrared range (at 750 nm). The surface bidirectional reflectance depends on the composition but also on the surface microtexture such as the grain size distribution, morphology, internal structure and surface roughness, tracers of the geological processes. The Hapke semi-analytical model of radiative transfer in granular medium is used to model the surface bidirectional reflectance estimated at 750 nm from the orbital measurements after an atmospheric correction. The model depends on different radiative properties (e.g., single scattering albedo, grain phase function and regolith roughness) related to the surface composition and microtexture. In particular previous laboratory works showed that the particle phase function parameters, which describe the characteristics of the

  10. Quasi-liquid states observed on ion beam microtextured surfaces

    NASA Technical Reports Server (NTRS)

    Rossnagel, S. M.; Robinson, R. S.

    1982-01-01

    Liquid-like properties have been observed on surface structures developed by means of ion beam microtexturing. The structures include cones, pyramids, or wavelike formations. The observed liquid-like effects are drips and ripples on the sides of cones, droplet formation, the apparent flow and coalescence of closely packed structures, wetting angle and other surface tension effects, and the bending of cones by additional heating. The bulk temperatures are in the range of 50-600 C. These effects are seen to some extent on Cu, Al, Au, Pb, and Ni substrates.

  11. EBSD analysis of the microtexture of Ba-hexaferrite samples

    NASA Astrophysics Data System (ADS)

    Koblischka-Veneva, A.; Koblischka, M. R.; Schmauch, J.; Chen, Y.; Harris, V. G.

    2010-01-01

    The microtexture of differently prepared Ba-hexaferrite samples is investigated by means of electron backscatter diffraction (EBSD). Kikuchi patterns are obtained with a high image quality, enabling a spatial resolution of the EBSD maps of about 20 nm. The spatially highly resolved EBSD mappings provide additional information (individual grain orientation, misorientation angles, grain size distribution) as compared to the standard analysis techniques, which can contribute to an optimization of the growth process. Furthermore, as the crystallographic orientation of each grain is known, an exact analysis of the grain aspect ratio becomes possible which provides further insight to the microstructural dependence of the magnetic properties of ferrites.

  12. Mineral phases and metals in baghouse dust from secondary aluminum production.

    PubMed

    Huang, Xiao-Lan; El Badawy, Amro M; Arambewela, Mahendranath; Adkins, Renata; Tolaymat, Thabet

    2015-09-01

    Baghouse dust (BHD) is a solid waste generated by air pollution control systems during secondary aluminum processing (SAP). Management and disposal of BHD can be challenging in the U.S. and elsewhere. In this study, the mineral phases, metal content and metal leachability of 78 BHD samples collected from 13 different SAP facilities across the U.S. were investigated. The XRD semi-quantitative analysis of BHD samples suggests the presence of metallic aluminum, aluminum oxide, aluminum nitride and its oxides, spinel, elpasolite as well as diaspora. BHD also contains halite, sylvite and fluorite, which are used as fluxes in SAP activities. Total aluminum (Al) in the BHD samples averaged 18% by weight. Elevated concentrations of trace metals (>100 μg L(-1) As; >1000 μg L(-1) Cu, Mn, Se, Pb, Mn and Zn) were also detected in the leachate. The U.S. toxicity characteristic leaching procedure (TCLP) results showed that some samples leached above the toxicity limit for Cd, Pb and Se. Exceeding the TCLP limits in all sample is independent of facilities generating the BHD. From the metal content perspective only, it appears that BHD has a higher potential to exhibit toxicity characteristics than salt cake (the largest waste stream generated by SAP facilities). PMID:25898346

  13. 9 M.y. record of southern Nevada climate from Yucca Mountain secondary minerals

    SciTech Connect

    Whelan, J.F.; Moscati, R.J.

    1998-12-01

    Yucca Mountain, Nevada, is presently the object of intense study as a potential permanent repository for the Nation`s high-level radioactive wastes. The mountain consists of a thick sequence of volcanic tuffs within which the depth to water table ranges from 500 to 700 meters below the land surface. This thick unsaturated zone (UZ), which would host the projected repository, coupled with the present day arid to semi-arid climate, is considered a favorable attribute of the site. Evaluation of the site includes defining the relation between climate variability, as the input function or driver of site- and regional-scale ground-water flow, and the possible future transport and release of radionuclides to the accessible environment. Secondary calcite and opal have been deposited in the UZ by meteoric waters that infiltrated through overlying soils and percolated through the tuffs. The oxygen isotopic composition ({delta}{sup 18}O values) of these minerals reflect contemporaneous meteoric waters and the {delta}{sup 13}C values reflect soil organic matter, and hence the resident plant community, at the time of infiltration. Recent U/Pb age determinations of opal in these occurrences, coupled with the {delta}{sup 13}C values of associated calcite, allow broadbrush reconstructions of climate patterns during the past 9 M.y.

  14. Mineral phases and metals in baghouse dust from secondary aluminum production.

    PubMed

    Huang, Xiao-Lan; El Badawy, Amro M; Arambewela, Mahendranath; Adkins, Renata; Tolaymat, Thabet

    2015-09-01

    Baghouse dust (BHD) is a solid waste generated by air pollution control systems during secondary aluminum processing (SAP). Management and disposal of BHD can be challenging in the U.S. and elsewhere. In this study, the mineral phases, metal content and metal leachability of 78 BHD samples collected from 13 different SAP facilities across the U.S. were investigated. The XRD semi-quantitative analysis of BHD samples suggests the presence of metallic aluminum, aluminum oxide, aluminum nitride and its oxides, spinel, elpasolite as well as diaspora. BHD also contains halite, sylvite and fluorite, which are used as fluxes in SAP activities. Total aluminum (Al) in the BHD samples averaged 18% by weight. Elevated concentrations of trace metals (>100 μg L(-1) As; >1000 μg L(-1) Cu, Mn, Se, Pb, Mn and Zn) were also detected in the leachate. The U.S. toxicity characteristic leaching procedure (TCLP) results showed that some samples leached above the toxicity limit for Cd, Pb and Se. Exceeding the TCLP limits in all sample is independent of facilities generating the BHD. From the metal content perspective only, it appears that BHD has a higher potential to exhibit toxicity characteristics than salt cake (the largest waste stream generated by SAP facilities).

  15. Human Mesenchymal Stem Cell Morphology and Migration on Microtextured Titanium

    PubMed Central

    Banik, Brittany L.; Riley, Thomas R.; Platt, Christina J.; Brown, Justin L.

    2016-01-01

    The implant used in spinal fusion procedures is an essential component to achieving successful arthrodesis. At the cellular level, the implant impacts healing and fusion through a series of steps: first, mesenchymal stem cells (MSCs) need to adhere and proliferate to cover the implant; second, the MSCs must differentiate into osteoblasts; third, the osteoid matrix produced by the osteoblasts needs to generate new bone tissue, thoroughly integrating the implant with the vertebrate above and below. Previous research has demonstrated that microtextured titanium is advantageous over smooth titanium and PEEK implants for both promoting osteogenic differentiation and integrating with host bone tissue; however, no investigation to date has examined the early morphology and migration of MSCs on these surfaces. This study details cell spreading and morphology changes over 24 h, rate and directionality of migration 6–18 h post-seeding, differentiation markers at 10 days, and the long-term morphology of MSCs at 7 days, on microtextured, acid-etched titanium (endoskeleton), smooth titanium, and smooth PEEK surfaces. The results demonstrate that in all metrics, the two titanium surfaces outperformed the PEEK surface. Furthermore, the rough acid-etched titanium surface presented the most favorable overall results, demonstrating the random migration needed to efficiently cover a surface in addition to morphologies consistent with osteoblasts and preosteoblasts. PMID:27243001

  16. Volcanic stratigraphy and secondary mineralization of U. S. G. S. Pucci geothermal test well, Mount Hood, Oregon

    SciTech Connect

    Gannett, M.W.; Bargar, K.E.

    1981-01-01

    Ninety-one sample splits of drill cuttings from approximately 6.1 m intervals in the 610 m hole that was completed in 1979 were provided for this study. An additional 225 sample splits (3.05 m intervals) from 536 m to the bottom of the drill hole at 1220 m were added to the study following the deepening of the drill hole. Stratigraphic and petrologic observations of the cuttings were made. Scanning electron microscope and x-ray diffractometer examinations were made of alteration minerals. The lithology and secondary mineralization are discussed.

  17. Secondary uranium mineralization in southern Finland and its relationship to recent glacial events

    NASA Astrophysics Data System (ADS)

    Read, David; Black, Stuart; Buckby, Tracy; Hellmuth, Karl-Heinz; Marcos, Nuria; Siitari-Kauppi, Marja

    2008-02-01

    Uranium series dating has been carried out on secondary uranyl silicate minerals formed during sub-glacial and post-glacial weathering of Proterozoic uraninite ores in south west Finland. The samples were obtained from two sites adjacent to the Salpauselkä III ice marginal formation and cover a range of depths, from the surface to more than 60 m. Measured ages fall into three distinct groups, 70-100 ka, 28-36 ka and < 2500 yr. The youngest set is associated with surface exposures and the crystals display clear evidence of re-working. The most likely trigger for uranium release at depths below the surface weathering zone is intrusion of oxidising glacial melt water. The latter is often characterised by very high discharge rates along channels, which close once the overpressure generated at the ice margin is released. There is excellent correspondence between the two Finnish sites and published data for similar deposits over a large area of southern and central Sweden. None of the seventy samples analysed gave a U-Th age between 40 and 70 ka; a second hiatus is apparent at 20 ka, coinciding with the Last Glacial Maximum. Thus, the process responsible for uranyl silicate formation was halted for significant periods, owing to a change in geochemical conditions or the hydrogeological regime. These data support the presence of interstadial conditions during the Early and Middle Weichselian since in the absence of major climatic perturbations the uranium phases at depth are stable. When viewed in conjunction with proxy data from mammoth remains it would appear that the region was ice-free prior to the Last Glacial Maximum.

  18. Radionuclide Incorporation in Secondary Crystalline Minerals Resulting from Chemical Weathering of Selected Waste Glasses: Progress Report for Subtask 3d

    SciTech Connect

    SV Mattigod; DI Kaplan; VL LeGore; RD Orr; HT Schaef; JS Young

    1998-10-23

    Experiments were conducted in fiscal year 1998 by Pacific Northwest National Laboratory to evaluate potential incorporation of radionuclides in secondary mineral phases that form from weathering vitrified nuclear waste glasses. These experiments were conducted as part of the Immobilized Low- Activity Waste-Petiormance Assessment (ILAW-PA) to generate data on radionuclide mobilization and transport in a near-field enviromnent of disposed vitrified wastes. An initial experiment was conducted to identify the types of secondary minerals that form from two glass samples of differing compositions, LD6 and SRL202. Chemical weathering of LD6 glass at 90oC in contact with an aliquot of uncontaminated Hanford Site groundwater resulted in the formation of a Crystalline zeolitic mineral, phillipsite. In contrast similar chemical weathering of SRL202 glass at 90"C resulted in the formation of a microcrystalline smectitic mineral, nontronite. A second experiment was conducted at 90"C to assess the degree to which key radionuclides would be sequestered in the structure of secondary crystalline minerals; namely, phillipsite and nontronite. Chemical weathering of LD6 in contact with radionuclide-spiked Hanford Site groundwater indicated that substantial ilactions of the total activities were retained in the phillipsite structure. Similar chemical weathering of SRL202 at 90"C, also in contact with radionuclide-spiked Hanford Site groundwater, showed that significant fractions of the total activities were retained in the nontronite structure. These results have important implications regarding the radionuclide mobilization aspects of the ILAW-PA. Additional studies are required to confkm the results and to develop an improved under- standing of mechanisms of sequestration and attenuated release of radionuclides to help refine certain aspects of their mobilization.

  19. Proterozoic polymetamorphism in the Quanji Block, northwestern China: Evidence from microtextures, garnet compositions and monazite CHIME ages

    NASA Astrophysics Data System (ADS)

    Wang, Qinyan; Pan, Yuanming; Chen, Nengsong; Li, Xiaoyan; Chen, Haihong

    2009-05-01

    The Quanji Block, situated close to the triple junction of three major Precambrian terranes in China (i.e., the North China Craton, the Yangtze Block and the Tarim Block), is composed of Precambrian metamorphic crystalline basement and an unmetamorphosed Mesozoic-Paleozoic sedimentary cover; it has been interpreted as a remnant continental fragment. Microtextural relationships, garnet trace element compositions, and monazite CHIME ages in paragneisses, schists and granitic leucosomes show two episodes of regional metamorphism in the Quanji Block basement. The first regional metamorphism and accompaning anatexis took place at ˜1.93 Ga; the second regional metamorphism occurred between ˜1.75 and ˜1.71 Ga. Mineral compositions of the first metamorphism, including those of monazite, were significantly disturbed by the second event. These two regional metamorphic episodes were most likely linked to assembly and breakup of the supercontinent Columbia, respectively.

  20. Comparison of microstructure of superplastically deformed synthetic materials and ultramylonite: Coalescence of secondary mineral grains via grain boundary sliding

    NASA Astrophysics Data System (ADS)

    Hiraga, T.; Miyazaki, T.; Tasaka, M.; Yoshida, H.

    2011-12-01

    Using very fine-grained aggregates of forsterite containing ~10vol% secondary mineral phase such as periclase and enstatite, we have been able to demonstrate their superplascity, that is, achievement of more than a few 100 % tensile strain (Hiraga et al. 2010). Superplastic deformation is commonly considered to proceed via grain boundary sliding (GBS) which results in grain switching in the samples. Hiraga et al. (2010) succeeded in detecting the operation of GBS from observing the coalescence of grains of secondary phase in superplastically deformed samples. The secondary phase pins the motion of grain boundaries of the primary phase; however, the reduction of the number of the grains of secondary phase due to their coalescence allows grain growth of the primary phase. We analyzed the relationships between grain size of the primary and secondary phases, between strain and grain size, and between strain and the number of coalesced grains in the superplastically deformed samples. The results supports participation of all the grains of the primary phase in grain switching process indicating that the grain boundary sliding accommodates almost entire strain during the deformation. Mechanical properties of these materials such as their stress and grain size exponents of 1-2 do not conflict this conclusion. We applied the relationships obtained from analyzing superplastic materials to the microstructure of the natural samples, which has been considered to have deformed via grain boundary sliding, that is, ultramylonite. The microstructure of greenschist-grade ultramylonite reported by Fliervoet et al. (1997) was analyzed. Distributions of the mineral phases (i.e., quartz, plagioclase, K-feldspar and biotite) show distinct coalescence of the same mineral phases in the direction almost perpendicular to the foliation of the rock. The number of coalesced grains indicates that the strain that rock experienced is > 2. [reference] Hiraga et al. (2010) Nature 468, 1091

  1. The role of reaction affinity and secondary minerals in regulating chemical weathering rates at the Santa Cruz Soil Chronosequence, California

    NASA Astrophysics Data System (ADS)

    Maher, Kate; Steefel, Carl I.; White, Art F.; Stonestrom, Dave A.

    2009-05-01

    In order to explore the reasons for the apparent discrepancy between laboratory and field weathering rates and to determine the extent to which weathering rates are controlled by the approach to thermodynamic equilibrium, secondary mineral precipitation, and flow rates, a multicomponent reactive transport model (CrunchFlow) was used to interpret soil profile development and mineral precipitation and dissolution rates at the 226 ka Marine Terrace Chronosequence near Santa Cruz, CA. Aqueous compositions, fluid chemistry, transport, and mineral abundances are well characterized [White A. F., Schulz M. S., Vivit D. V., Blum A., Stonestrom D. A. and Anderson S. P. (2008) Chemical weathering of a Marine Terrace Chronosequence, Santa Cruz, California. I: interpreting the long-term controls on chemical weathering based on spatial and temporal element and mineral distributions. Geochim. Cosmochim. Acta72 (1), 36-68] and were used to constrain the reaction rates for the weathering and precipitating minerals in the reactive transport modeling. When primary mineral weathering rates are calculated with either of two experimentally determined rate constants, the nonlinear, parallel rate law formulation of Hellmann and Tisserand [Hellmann R. and Tisserand D. (2006) Dissolution kinetics as a function of the Gibbs free energy of reaction: An experimental study based on albite feldspar. Geochim. Cosmochim. Acta70 (2), 364-383] or the aluminum inhibition model proposed by Oelkers et al. [Oelkers E. H., Schott J. and Devidal J. L. (1994) The effect of aluminum, pH, and chemical affinity on the rates of aluminosilicate dissolution reactions. Geochim. Cosmochim. Acta58 (9), 2011-2024], modeling results are consistent with field-scale observations when independently constrained clay precipitation rates are accounted for. Experimental and field rates, therefore, can be reconciled at the Santa Cruz site. Additionally, observed maximum clay abundances in the argillic horizons occur at the

  2. The role of reaction affinity and secondary minerals in regulating chemical weathering rates at the Santa Cruz Soil Chronosequence, California

    USGS Publications Warehouse

    Maher, K.; Steefel, Carl; White, A.F.; Stonestrom, D.A.

    2009-01-01

    In order to explore the reasons for the apparent discrepancy between laboratory and field weathering rates and to determine the extent to which weathering rates are controlled by the approach to thermodynamic equilibrium, secondary mineral precipitation, and flow rates, a multicomponent reactive transport model (CrunchFlow) was used to interpret soil profile development and mineral precipitation and dissolution rates at the 226 ka Marine Terrace Chronosequence near Santa Cruz, CA. Aqueous compositions, fluid chemistry, transport, and mineral abundances are well characterized [White A. F., Schulz M. S., Vivit D. V., Blum A., Stonestrom D. A. and Anderson S. P. (2008) Chemical weathering of a Marine Terrace Chronosequence, Santa Cruz, California. I: interpreting the long-term controls on chemical weathering based on spatial and temporal element and mineral distributions. Geochim. Cosmochim. Acta 72 (1), 36-68] and were used to constrain the reaction rates for the weathering and precipitating minerals in the reactive transport modeling. When primary mineral weathering rates are calculated with either of two experimentally determined rate constants, the nonlinear, parallel rate law formulation of Hellmann and Tisserand [Hellmann R. and Tisserand D. (2006) Dissolution kinetics as a function of the Gibbs free energy of reaction: An experimental study based on albite feldspar. Geochim. Cosmochim. Acta 70 (2), 364-383] or the aluminum inhibition model proposed by Oelkers et al. [Oelkers E. H., Schott J. and Devidal J. L. (1994) The effect of aluminum, pH, and chemical affinity on the rates of aluminosilicate dissolution reactions. Geochim. Cosmochim. Acta 58 (9), 2011-2024], modeling results are consistent with field-scale observations when independently constrained clay precipitation rates are accounted for. Experimental and field rates, therefore, can be reconciled at the Santa Cruz site. Additionally, observed maximum clay abundances in the argillic horizons occur at

  3. Coupled alkali feldspar dissolution and secondary mineral precipitation in batch systems: 4. Numerical modeling of kinetic reaction paths

    NASA Astrophysics Data System (ADS)

    Zhu, Chen; Lu, Peng; Zheng, Zuoping; Ganor, Jiwchar

    2010-07-01

    This paper explores how dissolution and precipitation reactions are coupled in batch reactor experimental systems at elevated temperatures. This is the fourth paper in our series of "Coupled Alkali Feldspar Dissolution and Secondary Mineral Precipitation in Batch Systems". In our third paper, we demonstrated via speciation-solubility modeling that partial equilibrium between secondary minerals and aqueous solutions was not attained in feldspar hydrolysis batch reactors at 90-300 °C and that a strong coupling between dissolution and precipitation reactions follows as a consequence of the slower precipitation of secondary minerals ( Zhu and Lu, 2009). Here, we develop this concept further by using numerical reaction path models to elucidate how the dissolution and precipitation reactions are coupled. Modeling results show that a quasi-steady state was reached. At the quasi-steady state, dissolution reactions proceeded at rates that are orders of magnitude slower than the rates measured at far from equilibrium. The quasi-steady state is determined by the relative rate constants, and strongly influenced by the function of Gibbs free energy of reaction ( ΔG) in the rate laws. To explore the potential effects of fluid flow rates on the coupling of reactions, we extrapolate a batch system ( Ganor et al., 2007) to open systems and simulated one-dimensional reactive mass transport for oligoclase dissolution and kaolinite precipitation in homogeneous porous media. Different steady states were achieved at different locations along the one-dimensional domain. The time-space distribution and saturation indices (SI) at the steady states were a function of flow rates for a given kinetic model. Regardless of the differences in SI, the ratio between oligoclase dissolution rates and kaolinite precipitation rates remained 1.626, as in the batch system case ( Ganor et al., 2007). Therefore, our simulation results demonstrated coupling among dissolution, precipitation, and flow rates

  4. Minerals and rocks, what a passion! A CLIL unit in an Italian lower secondary class

    NASA Astrophysics Data System (ADS)

    Papini, Piera; Fiorineschi, Beatrice

    2015-04-01

    CLIL means Content and Language Integrated Learning. Since September 2014 the teaching of a discipline in a foreign language has been compulsory in the final year of all high schools of Italy and recommended in lower secondary schools. So I decided to take part in a training course about "CLIL in Sciences teaching " that ANISN (Associazione Nazionale Insegnanti di Scienze Naturali ) was being held in Bologna from October to December 2014. There I learned that CLIL is much more than the translation of a traditional lecture to a foreign language. It is actually a set of new methodologies, largely based on Bloom's taxonomy, and making use of many kinds of technical support often referred to as "scaffolding" . It provides a context to improve communication because "natural language is never learned divorced from meaning". But CLIL is even more effective in order to learn the content, which is more important here than in immersion methodology. In the course we had to chose a subject , develop it in a structured unit, experiment the unit in a class of ours, using just English, and finally present it to the colleagues in Bologna. I decided to do the activity with 13 year old students. We had started the science lessons with chemistry, this year and I needed a subject consistent with that. So the choice was: Minerals! Because they belong to chemistry, being chemical compounds. Subsequently, even when the course in Bologna had come to an end, we continued with: Rocks! Since the pupils were pleased to do it and I was satisfied with their results. I worked together with my colleague who teaches English in the same class. We developed the subject following the instructions I had been given at the course: we showed the students videos found on line, providing them with the script; we made the text easier for them; we made them work in couples; I organized lab activities to improve learning skills to which they could apply their knowledge . Cross - curricolar links are an

  5. Secondary ion mass spectrometric investigation of penetration of coconut and mineral oils into human hair fibers: relevance to hair damage.

    PubMed

    Ruetsch, S B; Kamath, Y K; Rele, A S; Mohile, R B

    2001-01-01

    An attempt has been made to show the difference in the penetrability of coconut oil and mineral oil in human hair. We have used secondary ion mass spectrometry (SIMS) in combination with a time-of-flight (TOF) mass spectrometer. Characteristic ions formed by the pure components when bombarded with gallium ions have been identified with their m/z values. The distribution of the ion, characteristic of the particular treatment, has been established in the cross sections of hair treated with coconut and mineral oils. The results show that coconut oil penetrates the hair shaft while mineral oil does not. The difference may be due to the polarity of the coconut oil compared to the nonpolar nature of the mineral oil. The affinity of the penetrant to the protein seems to be the cause for this difference in their behavior. This study also indicates that the swelling of hair is limited by the presence oil. Since the process of swelling and deswelling of hair is one of the causes of hair damage by hygral fatigue, coconut oil, which is a better penetrant than mineral oil, may provide better protection from damage by hygral fatigue.

  6. Bone growth enhancement in vivo on press-fit titanium alloy implants with acid etched microtexture.

    PubMed

    Daugaard, Henrik; Elmengaard, Brian; Bechtold, Joan E; Soballe, Kjeld

    2008-11-01

    Early bone ongrowth secures long-term fixation of primary implants inserted without cement. Implant surfaces roughened with a texture on the micrometer scale are known to be osseoconductive. The aim of this study was to evaluate the bone formation at the surface of acid etched implants modified on the micro-scale. We compared implants with a nonparticulate texture made by chemical milling (hydrofluoric acid, nitric acid) (control) with implants that had a dual acid etched (hydrofluoric acid, hydrochloric acid) microtexture surface superimposed on the primary chemically milled texture. We used an experimental joint replacement model with cylindrical titanium implants (Ti-6Al-4V) inserted paired and press-fit in cancellous tibia metaphyseal bone of eight canines for 4 weeks and evaluated by histomorphometric quantification. A significant twofold median increase was seen for bone ongrowth on the acid etched surface [median, 36.1% (interquartile range, 24.3-44.6%)] compared to the control [18.4% (15.6-20.4%)]. The percentage of fibrous tissue at the implant surface and adjacent bone was significantly less for dual acid textured implants compared with control implants. These results show that secondary roughening of titanium alloy implant surface by dual acid etching increases bone formation at the implant bone interface. PMID:18186059

  7. Bone growth enhancement in vivo on press-fit titanium alloy implants with acid etched microtexture

    PubMed Central

    Daugaard, Henrik; Elmengaard, Brian; Bechtold, Joan E.; Soballe, Kjeld

    2013-01-01

    Early bone ongrowth secures long-term fixation of primary implants inserted without cement. Implant surfaces roughened with a texture on the micrometer scale are known to be osseoconductive. The aim of this study was to evaluate the bone formation at the surface of acid etched implants modified on the micro-scale. We compared implants with a nonparticulate texture made by chemical milling (hydrofluoric acid, nitric acid) (control) with implants that had a dual acid etched (hydrofluoric acid, hydrochloric acid) microtexture surface superimposed on the primary chemically milled texture. We used an experimental joint replacement model with cylindrical titanium implants (Ti-6Al-4V) inserted paired and press-fit in cancellous tibia metaphyseal bone of eight canines for 4 weeks and evaluated by histomorphometric quantification. A significant twofold median increase was seen for bone ongrowth on the acid etched surface [median, 36.1% (interquartile range, 24.3–44.6%)] compared to the control [18.4% (15.6–20.4%)]. The percentage of fibrous tissue at the implant surface and adjacent bone was significantly less for dual acid textured implants compared with control implants. These results show that secondary roughening of titanium alloy implant surface by dual acid etching increases bone formation at the implant bone interface. PMID:18186059

  8. A granulometry and secondary mineral fingerprint of chemical weathering in periglacial landscapes and its application to blockfield origins

    NASA Astrophysics Data System (ADS)

    Goodfellow, Bradley W.

    2012-12-01

    A review of published literature was undertaken to determine if there was a fingerprint of chemical weathering in regoliths subjected to periglacial conditions during their formation. If present, this fingerprint would be applied to the question of when blockfields in periglacial landscapes were initiated. These blocky diamicts are usually considered to represent remnants of regoliths that were chemically weathered under a warm, Neogene climate and therefore indicate surfaces that have undergone only a few metres to a few 10s of metres of erosion during the Quaternary. Based on a comparison of clay and silt abundances and secondary mineral assemblages from blockfields, other regoliths in periglacial settings, and regoliths from non-periglacial settings, a fingerprint of chemical weathering in periglacial landscapes was identified. A mobile regolith origin under, at least seasonal, periglacial conditions is indicated where clay(%) ≤ 0.5*silt(%) + 8 across a sample batch. This contrasts with a mobile regolith origin under non-periglacial conditions, which is indicated where clay(%) ≥ 0.5*silt(%) - 6 across a sample batch with clay(%) ≥ 0.5*silt(%) + 8 in at least one sample. A range of secondary minerals, which frequently includes interstratified minerals and indicates high local variability in leaching conditions, is also commonly present in regoliths exposed to periglacial conditions during their formation. Clay/silt ratios display a threshold response to temperature, related to the freezing point of water, but there is little response to precipitation or regolith residence time. Lithology controls clay and silt abundances, which increase from felsic, through intermediate, to mafic compositions, but does not control clay/silt ratios. Use of a sedigraph or Coulter Counter to determine regolith granulometry systematically indicates lower clay abundances and intra-site variability than use of a pipette or hydrometer. In contrast to clay/silt ratios, secondary

  9. Secondary Mineral Deposits and Evidence of Past Seismicity and Heating of the Proposed Repository Horizon at Yucca Mountain, Nevada

    USGS Publications Warehouse

    Whelan, Josheph F.

    2004-01-01

    The Drift Degradation Analysis (DDA) (BSC, 2003) for the proposed high-level radioactive waste repository at Yucca Mountain, Nevada, describes model simulations of the effects of pre- and post-closure seismicity and waste-induced heating on emplacement drifts. Based on probabilistic seismic hazard analyses of the intensity and frequency of future seismic events in the region (CRWMS M&O, 1998), the DDA concludes that future seismicity will lead to substantial damage to emplacement drifts, particularly those in the lithophysal tuffs, where some simulations predict complete collapse of the drift walls. Secondary mineral studies conducted by the U.S. Geological Survey since 1995 indicate that secondary calcite and silica have been deposited in some fractures and lithophysal cavities in the unsaturated zone (UZ) at Yucca Mountain during at least the past 10 million years (m.y.), and probably since the tuffs cooled to less than 100?C. Tuff fragments, likely generated by past seismic activity, have commonly been incorporated into the secondary mineral depositional sequences. Preliminary observations indicate that seismic activity has generated few, if any, tuff fragments during the last 2 to 4 m.y., which may be inconsistent with the predictions of drift-wall collapse described in the DDA. Whether or not seismicity-induced tuff fragmentation occurring at centimeter to decimeter scales in the fracture and cavity openings relates directly to failure of tuff walls in the 5.5-m-diameter waste emplacement drifts, the deposits do provide a potential record of the spatial and temporal distribution of tuff fragments in the UZ. In addition, the preservation of weakly attached coatings and (or) delicate, upright blades of calcite in the secondary mineral deposits provides an upper limit for ground motion during the late stage of deposition that might be used as input to future DDA simulations. Finally, bleaching and alteration at a few of the secondary mineral sites indicate that

  10. Coupled alkai fieldspar dissolution and secondary mineral precipatation in batch systems-2: New experiments with supercritical CO2 and implications for carbon sequestration

    SciTech Connect

    Lu, Peng; Fu, Qi; Seyfried, William E. Jr.; Hedges, Sheila W.; Soong, Yee; Jones, Kyle; Zhua, Chen

    2013-01-01

    In order to evaluate the extent of CO{sub 2}–water–rock interactions in geological formations for C sequestration, three batch experiments were conducted on alkali feldspars–CO{sub 2}–brine interactions at 150–200 °C and 300 bars. The elevated temperatures were necessary to accelerate the reactions to facilitate attainable laboratory measurements. Temporal evolution of fluid chemistry was monitored by major element analysis of in situ fluid samples. SEM, TEM and XRD analysis of reaction products showed extensive dissolution features (etch pits, channels, kinks and steps) on feldspars and precipitation of secondary minerals (boehmite, kaolinite, muscovite and paragonite) on feldspar surfaces. Therefore, these experiments have generated both solution chemistry and secondary mineral identity. The experimental results show that partial equilibrium was not attained between secondary minerals and aqueous solutions for the feldspar hydrolysis batch systems. Evidence came from both solution chemistry (supersaturation of the secondary minerals during the entire experimental duration) and metastable co-existence of secondary minerals. The slow precipitation of secondary minerals results in a negative feedback in the dissolution–precipitation loop, reducing the overall feldspar dissolution rates by orders of magnitude. Furthermore, the experimental data indicate the form of rate laws greatly influence the steady state rates under which feldspar dissolution took place. Negligence of both the mitigating effects of secondary mineral precipitation and the sigmoidal shape of rate–ΔG{sub r} relationship can overestimate the extent of feldspar dissolution during CO{sub 2} storage. Finally, the literature on feldspar dissolution in CO{sub 2}-charged systems has been reviewed. The data available are insufficient and new experiments are urgently needed to establish a database on feldspar dissolution mechanism, rates and rate laws, as well as secondary mineral

  11. Secondary minerals of weathered orpiment-realgar-bearing tailings in Shimen carbonate-type realgar mine, Changde, Central China

    NASA Astrophysics Data System (ADS)

    Zhu, Xiangyu; Wang, Rucheng; Lu, Xiancai; Liu, Huan; Li, Juan; Ouyang, Bingjie; Lu, Jianjun

    2015-02-01

    The formation and dissolution of arsenic minerals commonly controls the mobility of As in sulfide mines. Here, we present the results of research based on X-ray powder diffraction (XRD), Raman microprobe spectrum, scanning electron microscope (SEM), and transmission electron microscope (TEM) analyses, Scanning transmission X-ray microscope (STXM) and X-ray absorption fine structure (XAFS) analyses to further understand the weathering of orpiment- and realgar-bearing tailings from the Shimen realgar deposit, the largest realgar deposit in Asia. These analyses indicate that four different types of As-bearing secondary minerals are present in the tailings, including arsenic oxides, arsenates, As-gypsum, and As-Fe minerals, and that arsenic in the tailings is present in +3 and +5 valence states. The precipitation of arsenates is attributed to the interaction between As-enriched run-off waters and carbonate minerals. The Ca-arsenates in the tailings are dominantly weilite and pharmacolite, both of which have Ca/As atomic ratios of 1. In addition, SO4 2-/HAsO4 2- substitution in gypsum is another important mechanism of arsenic precipitation.

  12. Mechanically robust superamphiphobic aluminum surface with nanopore-embedded microtexture.

    PubMed

    Barthwal, Sumit; Kim, Young Su; Lim, Si-Hyung

    2013-09-24

    A simple fabrication technique was developed for preparing a mechanically robust superamphiphobic surface on an aluminum (Al) plate. Dual geometric architectures with micro- and nanoscale structures were formed on the surface of the Al plate by a combination of simple chemical etching and anodization. This proposed methodology involves (1) fabrication of irregular microscale plateaus on the surface of the Al plate, (2) formation of nanopores, and (3) fluorination. Wettability measurements indicated that the fabricated Al surface became super-repellent toward a broad range of liquids with surface tension in the range 27.5-72 mN/m. By varying the anodization time, we measured and compared the effects of morphological change on the wettability. The adhesion property and mechanical durability of the fabricated superamphiphobic Al surface were evaluated by the Scotch tape and hardness tests, respectively. The results showed that the fabricated Al surface retained mechanical robustness because the down-directed surface made by nanopores on the microtextured surface was durable enough even after high force was applied. Almost no damage of the film was observed, and the surface still exhibited superamphiphobicity after the tests. The fabricated superamphiphobic surface also remained stable after long-term storage. The simple and time-saving fabrication technique can be extended to any large-area three-dimensional surface, making it potentially suitable for large-scale industrial fabrications of mechanically robust superamphiphobic surfaces.

  13. Radionuclide Incorporation in Secondary Crystalline Minerals Resulting from Chemical Weathering of Selected Waste Glasses: Progress Report: Task kd.5b

    SciTech Connect

    Mattigod, Shas V.; Serne, R. Jeffrey; Legore, Virginia L.; Parker, Kent E.; Orr, Robert D.; McCready, David E.; Young, James S.

    2003-09-29

    Experiments were conducted by Pacific Northwest National Laboratory to evaluate potential incorporation of radionuclides in secondary mineral phases that form from weathering vitrified nuclear waste glasses. These experiments were conducted as part of the Immobilized Low-Activity Waste-Performance Assessment (ILAW-PA) to generate data on radionuclide mobilization and transport in a near-field environment of disposed vitrified wastes. The results of these experiments demonstrated that radionuclide sequestration can be significantly enhanced by promoting the formation of cage structured minerals such as sodalite from weathering glasses. These results have important implications regarding radionuclide sequestration/mobilization aspects that are not currently accounted for in the ILAW PA. Additional studies are required to confirm the results and to develop an improved understanding of the mechanisms of sequestration of radionuclides into the secondary and tertiary weathering products of the ILAW glass to help refine how contaminants are released from the near-field disposal region out into the accessible environment. Of particular interest is to determine whether the contaminants remain sequestered in the glass weathering products for hundreds to thousands of years. If the sequestration can be shown to continue for long periods, another immobilization process can be added to the PA analysis and predicted risks should be lower than past predictions.

  14. Secondary alteration of the impactite and mineralization in the basal Tertiary sequence, Yaxcopoil-1, Chicxulub impact crater, Mexico

    NASA Astrophysics Data System (ADS)

    Ames, Doreen E.; Kjarsgaard, Ingrid M.; Pope, Kevin O.; Dressler, Burkhard; Pilkington, Mark

    2004-07-01

    The 65 Ma Chicxulub impact crater formed in the shallow coastal marine shelf of the Yucatán Platform in Mexico. Impacts into water-rich environments provide heat and geological structures that generate and focus sub-seafloor convective hydrothermal systems. Core from the Yaxcopoil-1 (Yax-1) hole, drilled by the Chicxulub Scientific Drilling Project (CSDP), allowed testing for the presence of an impact-induced hydrothermal system by: a) characterizing the secondary alteration of the 100 m-thick impactite sequence; and b) testing for a chemical input into the lower Tertiary sediments that would reflect aquagene hydrothermal plume deposition. Interaction of the Yax-1 impactites with seawater is evident through redeposition of the suevites (unit 1), secondary alteration mineral assemblages, and the subaqueous depositional environment for the lower Tertiary carbonates immediately overlying the impactites. The least-altered silicate melt composition intersected in Yax-1 is that of a calc-alkaline basaltic andesite with 53.4-56 wt% SiO2 (volatile-free). The primary mineralogy consists of fine microlites of diopside, plagioclase (mainly Ab 47), ternary feldspar (Ab 37 to 77), and trace apatite, titanite, and zircon. The overprinting alteration mineral assemblage is characterized by Mg-saponite, Kmontmorillonite, celadonite, K-feldspar, albite, Fe-oxides, and late Ca and Mg carbonates. Mg and K metasomatism resulted from seawater interaction with the suevitic rocks producing smectite-Kfeldspar assemblages in the absence of any mixed layer clay minerals, illite, or chlorite. Rare pyrite, sphalerite, galena, and chalcopyrite occur near the base of the impactites. These secondary alteration minerals formed by low temperature (0-150 °C) oxidation and fixation of alkalis due to the interaction of glass-rich suevite with down-welling seawater in the outer annular trough intersected at Yax-1. The alteration represents a cold, Mg-K-rich seawater recharge zone, possibly recharging

  15. The Effects of Secondary Mineral Precipitates on 90Sr Mobility at the Hanford Site, USA

    SciTech Connect

    Um, Wooyong; Wang, Guohui; Serne, R. Jeffrey

    2013-06-03

    The effects of secondary precipitates on 90Sr transport at the Hanford Site were investigated using quartz column experiments with simulated caustic tank waste leachates (STWL). Significantly enhanced retardation of Sr transport was observed in the column contacted with STWL due to Sr sorption and co-precipitation with neo-formed nitratecancrinite. However, the column results also suggest that neo-formed secondary precipitates could behave like native mobile colloids that can enhance Sr transport. Initially immobilized Sr within secondary precipitates could remobilize given a change in the porewater background conditions. The mobility of the neo-formed Sr-bearing precipitates increased with increased solution flow rate. In the field, porewater contents and flow rates can be changed by snowmelt (or storm water) events or artificial infiltration. The increased porewater flow rate caused by these events could affect the mobility of 90Sr-containing secondary precipitates, which can be a potential source for facilitated Sr transport in Hanford Site subsurface environments.

  16. Exchangeable and secondary mineral reactive pools of aluminium in coastal lowland acid sulfate soils.

    PubMed

    Yvanes-Giuliani, Yliane A M; Waite, T David; Collins, Richard N

    2014-07-01

    The use of coastal floodplain sulfidic sediments for agricultural activities has resulted in the environmental degradation of many areas worldwide. The generation of acidity and transport of aluminium (Al) and other metals to adjacent aquatic systems are the main causes of adverse effects. Here, a five-step sequential extraction procedure (SEP) was applied to 30 coastal lowland acid sulfate soils (CLASS) from north-eastern New South Wales, Australia. This enabled quantification of the proportion of aluminium present in 'water-soluble', 'exchangeable', 'organically-complexed', 'reducible iron(III) (oxyhydr)oxide/hydroxysulfate-incorporated' and 'amorphous Al mineral' fractions. The first three extractions represented an average of 5% of 'aqua regia' extractable Al and their cumulative concentrations were extremely high, reaching up to 4000 mg·kg(-1). Comparison of Al concentrations in the final two extractions indicated that 'amorphous Al minerals' are quantitatively a much more important sink for the removal of aqueous Al derived from the acidic weathering of these soils than reducible Fe(III) minerals. Correlations were observed between soil pH, dissolved and total organic carbon (DOC and TOC) and Al concentrations in organic carbon-rich CLASS soil horizons. These results suggest that complexation of Al by dissolved organic matter significantly increases soluble Al concentrations at pH values >5.0. As such, present land management practices would benefit with redefinition of an 'optimal' soil from pH ≥5.5 to ~4.8 for the preservation of aquatic environments adjacent to organic-rich CLASS where Al is the sole or principle inorganic contaminant of concern. Furthermore, it was observed that currently-accepted standard procedures (i.e. 1 M KCl extraction) to measure exchangeable Al concentrations in these types of soils severely underestimate exchangeable Al and a more accurate representation may be obtained through the use of 0.2 M CuCl2.

  17. Mineral Association Changes the Secondary Structure and Dynamics of Murine Amelogenin

    SciTech Connect

    Lu, J. X.; Xu, Y. S.; Buchko, G. W.; Shaw, W. J.

    2013-10-15

    Biomineralization proteins, present during the formation of hard tissues including bones, teeth, egg shells and nacre, result in the exquisite structures and properties of the resulting materials.[1] The structure of these proteins is often implicated in the control of the mineral properties, however very little structural data is available for the bulk of these proteins due to the difficulty in determining structures of immobilized proteins. Solid-state NMR is uniquely suited to the study of the structure of proteins bound to surfaces, demonstrated with the structural and orientation insights provided for the hydroxyapatite mineralization proteins statherin and the amelogenin, LRAP.[2] While these data are some of the only structural data available for this important class of protein, the experiments are often expensive and time consuming, due to the need to prepare and measure samples with isolated spin pairs, and are limited to a size of ~60 residues. In this work, we utilized a combination of 1D and recent 2D[3] solid-state NMR techniques along with a sparsely labelled sample to characterize the structure and dynamics of potential HAP binding residues of the 180 residue enamel protein, amelogenin. Amelogenin nanospheres and mineral bound amelogenin were investigated and a shift from unstructured to β-sheet structure was observed, along with a decrease in protein flexibility. This work provides the first molecular level structure and dynamic information of full-length amelogenin on the surface of hydroxyapatite (HAP) and within nanospheres, and demonstrates the ability to evaluate structural characteristics of large biomineralization proteins bound to their physiologically relevant surface. The research was performed at the Pacific Northwest National Laboratory (PNNL), a facility operated by Battelle for the U.S. Department of Energy, with a portion of it performed at the W.R. Wiley Environmental Molecular Sciences Laboratory (EMSL), a national scientific user

  18. Characterization of Secondary Mineral Grain Coatings and their Role as Diffusion-controlled Sinks and Sources for Metal Contaminants

    NASA Astrophysics Data System (ADS)

    Davis, J. A.; Guo, H.; Lai, B.; Kemner, K. M.; Ercius, P.; Fox, P. M.; Singer, D. M.; Minor, A.; Waychunas, G.

    2012-12-01

    Many important geochemical reactions occur at the mineral-water interface, including sorption and desorption reactions of contaminants. Fundamental knowledge of the kinetics of these processes is based primarily on experimental observations of reactions at faces of single crystals or macroscopic data from pure mineral powder suspensions. Sorption reactions at crystal faces are generally very fast, on the order of microseconds or less, with reaction times often limited only by film diffusion at the mineral-water interface. In well-stirred suspensions of aquifer sediments, however, sorptive equilibrium can take many hours or days to achieve steady-state concentrations. We have examined the potential reasons for sorption rate limitation using uranium(VI) sorption by sediments from a sandy aquifer in Savannah River, South Carolina (USA). U(VI) sorption by sand-sized grains from the aquifer is dominated by reaction with secondary mineral coatings on quartz and feldspar grains. The coatings studied were on the order of 15 microns in thickness (i.e., from quartz grain to aqueous solution) and composed primarily of clay minerals and hematite of varying particle size. Microfocused-XRF imaging of elemental concentrations (e.g., U, Fe) of polished cross-sections of the grain/coating contact showed strong spatial correlations of U and Fe within the coatings, regardless of the length of reaction time (30 minutes to 4 weeks). The spatial resolution of the μ-XRF technique is of the order of 2 microns in horizontal directions, but the uncertainty of the observed spatial gradients is high due to grain curvature away from the polished surface and fluorescence contributed from the entire 30 micron thickness of a typical grain/epoxy thin section. TEM characterization of focused-ion-beam (FIB), vertically-extracted samples of the grain-coating contact shows that complex pore networks exist within the coatings of variable dimensions and unknown connectivity. Using scanning TEM (STEM

  19. Syntrophic Effects in a Subsurface Clostridial Consortium on Fe(III)-(Oxyhydr)oxide Reduction and Secondary Mineralization

    SciTech Connect

    Shah, Madhavi; Lin, Chu-Ching; Kukkadapu, Ravi K.; Engelhard, Mark H.; Zhao, Xiuhong; Wang, Yangping; Barkay, Tamar; Yee, Nathan

    2013-07-09

    In this study, we cultivated from subsurface sediments an anaerobic Clostridia 25 consortium that was composed of a fermentative Fe-reducer Clostridium species (designated as 26 strain FGH) and a novel sulfate-reducing bacterium belonging to the Clostridia family 27 Vellionellaceae (designated as strain RU4). In pure culture, Clostridium sp. strain FGH mediated 28 the reductive dissolution/transformation of iron oxides during growth on peptone. When 29 Clostridium sp. FGH was grown with strain RU4 on peptone, the rates of iron oxide reduction 30 were significantly higher. Iron reduction by the consortium was mediated by multiple 31 mechanisms, including biotic reduction by Clostridium sp. FGH and biotic/abiotic reactions 32 involving biogenic sulfide by strain RU4. The Clostridium sp. FGH produced hydrogen during 33 fermentation, and the presence of hydrogen inhibited growth and iron reduction activity. The 34 sulfate-reducing partner strain RU4 was stimulated by the presence of H2 gas and generated 35 reactive sulfide which promoted the chemical reduction of the iron oxides. Characterization of 36 Fe(II) mineral products showed the formation of magnetite during ferrihydrite reduction, and 37 the precipitation of iron sulfides during goethite and hematite reduction. The results suggest an 38 important pathway for iron reduction and secondary mineralization by fermentative sulfate-39 reducing microbial consortia is through syntrophy-driven biotic/abiotic reactions with biogenic 40 sulfide.

  20. A patterned microtexture to reduce friction and increase longevity of prosthetic hip joints

    PubMed Central

    Chyr, Anthony; Qiu, Mingfeng; Speltz, Jared; Jacobsen, Ronald L.; Sanders, Anthony P.; Raeymaekers, Bart

    2014-01-01

    More than 285,000 total hip replacement surgeries are performed in the US each year. Most prosthetic hip joints consist of a cobalt-chromium (CoCr) femoral head that articulates with a polyethylene acetabular component, lubricated with synovial fluid. The statistical survivorship of these metal-on-polyethylene prosthetic hip joints declines significantly after 10 to 15 years of use, primarily as a result of polyethylene wear and wear debris incited disease. The current engineering paradigm to increase the longevity of prosthetic hip joints is to improve the mechanical properties of the polyethylene component, and to manufacture ultra-smooth articulating surfaces. In contrast, we show that adding a patterned microtexture to the ultra-smooth CoCr femoral head reduces friction when articulating with the polyethylene acetabular liner. The microtexture increases the load-carrying capacity and the thickness of the joint lubricant film, which reduces contact between the articulating surfaces. As a result, friction and wear is reduced. We have used a lubrication model to design the geometry of the patterned microtexture, and experimentally demonstrate reduced friction for the microtextured compared to conventional smooth surrogate prosthetic hip joints. PMID:25013240

  1. A patterned microtexture to reduce friction and increase longevity of prosthetic hip joints.

    PubMed

    Chyr, Anthony; Qiu, Mingfeng; Speltz, Jared; Jacobsen, Ronald L; Sanders, Anthony P; Raeymaekers, Bart

    2014-07-15

    More than 285,000 total hip replacement surgeries are performed in the US each year. Most prosthetic hip joints consist of a cobalt-chromium (CoCr) femoral head that articulates with a polyethylene acetabular component, lubricated with synovial fluid. The statistical survivorship of these metal-on-polyethylene prosthetic hip joints declines significantly after 10 to 15 years of use, primarily as a result of polyethylene wear and wear debris incited disease. The current engineering paradigm to increase the longevity of prosthetic hip joints is to improve the mechanical properties of the polyethylene component, and to manufacture ultra-smooth articulating surfaces. In contrast, we show that adding a patterned microtexture to the ultra-smooth CoCr femoral head reduces friction when articulating with the polyethylene acetabular liner. The microtexture increases the load-carrying capacity and the thickness of the joint lubricant film, which reduces contact between the articulating surfaces. As a result, friction and wear is reduced. We have used a lubrication model to design the geometry of the patterned microtexture, and experimentally demonstrate reduced friction for the microtextured compared to conventional smooth surrogate prosthetic hip joints.

  2. Effect of surface micro-texture on bubble dynamics and boiling critical heat flux

    NASA Astrophysics Data System (ADS)

    Dhillon, Navdeep; Buongiorno, Jacopo; Varanasi, Kripa

    2014-11-01

    We present results of an experimental study on the effect of surface texture on the dynamics of bubble growth and departure in pool boiling of water and correlate them to the measured values of critical heat flux (CHF) on these surfaces. Although it is well known that surface roughness or micro-texture has a significant impact on macroscale boiling parameters such as boiling heat transfer coefficient (HTC) and CHF, the physics underlying these processes is not well understood. Using high speed optical and infrared (IR) imaging, we explored the mechanism of single bubble growth and departure on micro-textured surfaces fabricated using photolithography techniques. Interestingly, we observed that the introduction of the micro-texture not only completely changed bubble dynamics and boiling surface thermal characteristics but there was a clear correlation between the micro-texture parameters and the salient bubble characteristics such as the departure diameter and frequency. To explain these results, we propose a physical model based on micro-texture-induced surface microflows supplementing the conventional bubble growth and departure theory based on buoyancy and capillary pinning forces, and verify it using CHF measurements. Funding for this project is provided by Chevron Corp.

  3. Framework for estimating potential wastes and secondary resources accumulated within an economy--a case study of construction minerals in Japan.

    PubMed

    Hashimoto, Seiji; Tanikawa, Hiroki; Moriguchi, Yuichi

    2009-11-01

    Material stocks in economic society are considered to represent a reserve for wastes and secondary resources. From the viewpoints of proper disposal and reutilization of stocked materials, accurate estimation of the amount of materials that will emerge as wastes or secondary resources in the future is important. We defined materials that have a high probability of emerging as wastes or secondary resources as "potential wastes and secondary resources" and estimated that amount for construction minerals in Japan as a case study. The following conclusions were drawn. (1) We classified materials that are input into economic society into four categories: potential wastes and secondary resources, potential dissipated materials, dissipatively used materials, and permanent structures. By clarifying the latter three non-potential wastes and secondary resources, we performed a more accurate assessment of the wastes and secondary resources that will emerge in the future. (2) The share of potential wastes and secondary resources was estimated to be about 30% of all construction minerals that have been input into and accumulated in Japanese economic society. (3) Information related to potential dissipated materials and dissipatively used materials will provide fundamental knowledge to support analyses of the environmental impacts and resource losses which these materials might generate.

  4. Evidence for biological activity in mineralization of secondary sulphate deposits in a basaltic environment: implications for the search for life in the Martian subsurface

    SciTech Connect

    C. Doc Richardson; Nancy W. Hinman; Jill R. Scott

    2013-10-01

    Evidence of microbial activity associated with mineralization of secondary Na-sulphate minerals (thenardite, mirabilite) in the basaltic subsurface of Craters of the Moon National Monument (COM), Idaho were examined by scanning electron microscopy, X-ray diffraction, laser desorption Fourier transform ion cyclotron resonance mass spectrometry (LD-FTICR-MS), Fourier transform infrared spectroscopy (FTIR) and isotope ratio mass spectrometry. Peaks suggestive of bio/organic compounds were observed in the secondary Na-sulphate deposits by LD-FTICR-MS. FTIR provided additional evidence for the presence of bio/organic compounds. Sulphur fractionation was explored to assist in determining if microbes may play a role in oxidizing sulphur. The presence of bio/organic compounds associated with Na-sulphate deposits, along with the necessity of oxidizing reduced sulphur to sulphate, suggests that biological activity may be involved in the formation of these secondary minerals. The secondary Na-sulphate minerals probably form from the overlying basalt through leached sodium ions and sulphate ions produced by bio-oxidation of Fe-sulphide minerals. Since the COM basalts are one of the most comparable terrestrial analogues for their Martian counterparts, the occurrence of biological activity in the formation of sulphate minerals at COM has direct implications for the search for life on Mars. In addition, the presence of caves on Mars suggests the importance of these environments as possible locations for growth and preservation of microbial activity. Therefore, understanding the physiochemical pathways of abiotic and biotic mineralization in the COM subsurface and similar basaltic settings has direct implications for the search for extinct or extant life on Mars.

  5. Field Observation of Heterogeneous Formation of Secondary Organic Aerosols on Asian Mineral Dust Surfaces

    NASA Astrophysics Data System (ADS)

    Wang, G.

    2014-12-01

    This study investigated the heterogeneous formation mechanism of secondary organic aerosols (SOA) on dust surfaces by characterizing molecular compositions and size distributions of dicarboxylic acids, keto-carboxylic acids, a-dicarbonyls and inorganic ions in size-segregated aerosols (9-stages) in the urban atmosphere of Xi'an, China during dust storm periods and comparing with those in non-dust storm periods. In the presence of a dust storm, all the above mentioned SOA species in Xi'an are predominantly enriched on coarse particles (>2.1 µm). Oxalic acid well correlated with NO3- (r2=0.72, p<0.01) rather than SO42-. This phenomenon differs greatly from the observed particles during a non-dust storm period, which is characterized by an enrichment of the SOA on fine particles (<2.1 µm) with a strong correlation between C2 and SO42-. We propose a three-step formation pathway to explain these observations as follows. First, nitric acid and nitrogen oxides react with dust to form a liquid film on the surface via water vapor-absorption of calcium nitrate. Second, gaseous Gly and mGly partition into the aqueous-phase. Finally, the aqueous-phase Gly and mGly oxidize into glyoxylic acid (wC2), followed by a further oxidation into C2. To the best of our knowledge, we found for the first time the enrichments of glyoxal (Gly) and methylglyoxal (mGly) on dust surfaces. Our data indicate a more critical role of nitrate than sulfate in the heterogeneous formation process of SOA on dust surfaces. Mass ratio of C2 to wC2 was found to be higher in coarse particles than in fine particles during the dust storm events, which is due to low acidity condition of large particles that is favorable for conversion of wC2 to C2.

  6. Microtextural Study of Feldspar in Petrologic Type 3 LL Ordinary Chondrites: A Record of Parent Body Metasomatism

    NASA Astrophysics Data System (ADS)

    Lewis, J. A.; Jones, R. H.

    2014-09-01

    We have carried out a detailed study of LL3 ordinary chondrites, focusing on the chemical and microtextural development of feldspar, to help understand the low-temperature evolution of the LL parent body(ies).

  7. Integrating hematite (U-Th)/He dating, microtextural analysis, and thermomechanical modeling to date seismic slip

    NASA Astrophysics Data System (ADS)

    McDermott, R.; Ault, A. K.; Evans, J. P.; Reiners, P. W.; Shuster, D. L.

    2015-12-01

    Linking petrologic and geochronologic evidence for seismicity in the rock record is challenging, yet critical for understanding slip mechanics in natural faults, structural histories, and modern seismic hazards. We couple hematite (U-Th)/He (HeHe) dating with microtextural analysis and thermomechanical modeling to decipher this record from locally iridescent, hematite-coated fault surfaces in the seismogenic Wasatch fault zone (WFZ), Utah. Prior study of one fault surface linked textural evidence for elevated temperatures with a pattern of HeHe dates to hypothesize that this surface preserves evidence of multiple seismic slip events. New scanning electron microscopy (SEM) and HeHe data from a larger sample suite test this hypothesis. The SEM images reveal the presence of <500 nm polygonal hematite crystals at some iridescent regions, suggesting co- to post-seismic hematite annealing and recrystallization at temperatures >800 °C. Fault surface samples yield 3.8 ± 0.03 to 1.5 ± 0.1 Ma dates, with younger dates in iridescent regions. These results are younger than 88.5 ± 15.0 Ma and 10.8 ± 0.8 Ma dates from veins associated with initial hematite mineralization as well as new apatite (U-Th)/He dates of 4.0 ± 0.6 Ma-5.4±1.1 Ma that constrain the footwall thermal history. Reproducible but statistically different HeHe dates from samples on the same fault surface are consistent with prior observations. Collectively, these observations suggest that hematite He dates record rapid cooling from localized shear heating at asperities to temperatures hot enough to reset the hematite He system. Models incorporate rate-dependent friction and half-space cooling to constrain shear zone temperature evolution. Results reveal temperatures >800 °C are sufficient to reset hematite up to 200 μm from the fault surface and HeHe dates may represent patches of rate-strengthening friction during seismic slip. Ongoing work utilizes SEM to target aliquots with textural evidence for

  8. Assessment of toxic potential of primary and secondary particulates/aerosols from biodiesel vis-à-vis mineral diesel fuelled engine.

    PubMed

    Agarwal, Avinash Kumar; Gupta, Tarun; Dixit, Neelabh; Shukla, Pravesh Chandra

    2013-05-01

    Toxicity of engine out emissions from primary and secondary aerosols has been a major cause of concern for human health and environmental impact. This study aims to evaluate comparative toxicity of nanoparticles emitted from a modern common rail direct injection engine (CRDI) fuelled with biodiesel blend (B20) vis-à-vis mineral diesel. The toxicity and potential health hazards of exhaust particles were assessed using various parameters such as nanoparticle size and number distribution, surface area distribution, elemental and organic carbon content and polycyclic aromatic hydrocarbons adsorbed onto the particle surfaces, followed by toxic equivalent factor assessment. It was found that biodiesel particulate toxicity was considerably lower in comparison to mineral diesel.

  9. Teasing apart the contributions of hard dietary items on 3D dental microtextures in primates.

    PubMed

    Calandra, Ivan; Schulz, Ellen; Pinnow, Mona; Krohn, Susanne; Kaiser, Thomas M

    2012-07-01

    3D dental microtexture analysis is a powerful tool for reconstructing the diets of extinct primates. This method is based on the comparison of fossils with extant species of known diet. The diets of primates are highly diversified and include fruits, seeds, grass, tree leaves, bark, roots, tubers, and animal resources. Fruits remain the main component in the diets of most primates. We tested whether the proportion of fruit consumed is correlated with dental microtexture. Two methods of microtexture analysis, the scale-sensitive fractal analysis (SSFA) and the Dental Areal Surface Texture Analysis (DASTA; after ISO/FDIS 25178-2), were applied to specimens of eight primate species (Alouatta seniculus, Gorilla gorilla, Lophocebus albigena, Macaca fascicularis, Pan troglodytes, Papio cynocephalus, Pongo abelii, Theropithecus gelada). These species largely differ in the mean annual proportion of fruit (from 0 to 90%) in their diet, as well as in their consumption of other hard items (seeds, bark, and insect cuticles) and of abrasive plants. We find the complexity and heterogeneity of textures (SSFA) to correlate with the proportion of fruits consumed. Textural fill volume (SSFA) indicates the proportion of both fruits and other hard items processed. Furthermore, anisotropy (SSFA) relates to the consumption of abrasive plants like grass and other monocots. ISO parameters valley height, root mean square height, material volume, density of peaks, and closed hill and dale areas (DASTA) describe the functional interaction between food items and enamel facets during mastication. The shallow, plastic deformation of enamel surfaces induced by small hard particles, such as phytoliths or dust, results in flat microtexture relief, whereas the brittle, deep fracture caused by large hard items such as hard seeds creates larger relief.

  10. Fabrication of Highly-Oleophobic and Superhydrophobic Surfaces on Microtextured al Substrates

    NASA Astrophysics Data System (ADS)

    Liu, Changsong; Zhou, Jigen; Zheng, Dongmei; Wan, Yong; Li, Zhiwen

    2011-06-01

    Theoretical calculations suggest that creating highly-oleophobic surfaces would require a surface energy lower than that of any known materials. In the present work, we demonstrate microtextured Al substrate surfaces with veins-like micro/nanostructures displaying apparent contact angles (CA) greater than 120°, even with nitromethane (surface tension γ1 = 37 mN/m). The Al substrate was microtextured by a chemical solution mixed by zinc nitrate hexahydrate, hexamethyltetramine and a little of hydrofluoric acid. A fluoroalkylsilane (FAS) agent was used to tune the surface wettability. The Al substrates were microtextured by veins-like micro/nanostructures and generating a solid-liquid-vapor composite interface. Combination with FAS modification, the Al surfaces resulted in an oleophobicity with CA for nitromethane was 126.3° (152.7° for diethylene glycol, γ1 = 45.2 mN/m). In addition, the Al surfaces demonstrated a low rolling-off angle with < 6° even for diethylene glycol. However, nitromethane droplet favored to pin on the sample surface even the sample stage is tilted to 90°. It is noted that this highly-oleophobic behavior is induced mainly by topography, which form a composite surface of air and solid with oil drop sitting partially on air. The results are expected to promote the study on self-cleaning applications, especially in the condition with oil contaminations.

  11. Towards near-permanent CoCrMo prosthesis surface by combining micro-texturing and low temperature plasma carburising.

    PubMed

    Dong, Yangchun; Svoboda, Petr; Vrbka, Martin; Kostal, David; Urban, Filip; Cizek, Jan; Roupcova, Pavla; Dong, Hanshan; Krupka, Ivan; Hartl, Martin

    2015-03-01

    An advanced surface engineering process combining micro-texture with a plasma carburising process was produced on CoCrMo femoral head, and their tribological properties were evaluated by the cutting-edge pendulum hip joint simulator coupled with thin film colorimetric interferometry. FESEM and GDOES showed that precipitation-free C S-phase with a uniform case depth of 10μm was formed across the micro-textures after duplex treatment. Hip simulator tests showed that the friction coefficient was reduced by 20% for micro-metre sized texture, and the long-term tribological property of microtexture was enhanced by the C-supersaturated crystalline microstructure formed on the surface of duplex treated CoCrMo, thereby enhancing biotribological durability significantly. In-situ colorimetric interferometry confirmed that the maximum film thickness around texture area was 530nm, indicating that the additional lubricant during sliding motion might provide exceptional bearing life. PMID:26594781

  12. Heavy minerals in surficial sediments from lower Cook Inlet, Alaska

    USGS Publications Warehouse

    Wong, F.L.

    1984-01-01

    Amphiboles, orthopyroxenes, and clinopyroxenes dominate the heavy mineral suite of surficial sediments in lower Cook Inlet, Alaska. Sources for these sediments include the igneous arc terrane of the northeast Alaska Range, reworked intrabasinal sediments, and local drainages in lower Cook Inlet. The distribution of these deposits is a reflection of both the tidal currents and the prevailing southerly net movement from the head of Cook Inlet. The heavy mineral studies concur with similar findings from gravel analyses, clay mineral investigations, and quartz microtexture observations. ?? 1984 Springer-Verlag New York Inc.

  13. Study of dolomite dissolution at various temperatures - Evidence for the formation of nanocrystalline secondary phases at dolomite surface and influence on dolomite interactions with other minerals

    NASA Astrophysics Data System (ADS)

    Debure, M.; Andreazza, P.; Grangeon, S.; Lerouge, C.; Montes-Hernandez, G.; MADE, B.; Tournassat, C.

    2015-12-01

    In most clay-rock geological formation studied for the storage of nuclear waste, pore water compositions are expected to be at equilibrium with carbonate minerals, which are always included in predictive models for pore water composition calculations [1]. Among the carbonates known to be present, dolomite may be problematic in the pore water composition calculation because its solubility spans a large range of values as a function of its crystallinity in thermodynamic databases. In addition, the composition of dolomite minerals observed in clay-rock formations such as Callovian-Oxfordian or Opalinus clay formation differs from this of a pure dolomite: the Ca/Mg stoichiometry is not ideal, and the minerals contain minor amounts of Fe and traces of many other elements [2]. To understand the influence of secondary phases precipitation during dolomite dissolution on pore water chemistry, the dissolution of monocrystals of dolomite were investigated at 25 °C and at 80 °C in a pH range 3 to 8 for various time periods (30 minutes to 21 days) in sealed PTFE reactors. Solution analyses evidenced a stoichiometric release of Ca and Mg in solution during dolomite dissolution. Scanning Electron Microscopy (SEM), Raman and X-Ray Diffraction (XRD) analyses did not evidence secondary Mg-bearing minerals precipitation, but revealed the formation of Fe-bearing particles on the dolomite surface. Morphological characterizations performed with Small-angle X-ray scattering (SAXS) evidenced that the precipitation occurs along a specific crystallographic plane of the dolomite monocrystal. Thus, the precipitated nanoparticles clustered on specific surface sites, and are made of Fe-rich phases poorly crystallized (carbonates, oxides and hydroxides). [1] Tournassat et al. 2015. Ch. 3: Chemical Conditions in Clay-Rocks. Natural and Engineered Clay Barriers, Elsevier. [2] Lerouge et al. 2011. Geochim. et Cosmoch. Acta, 2011, 75, 2633-2663.

  14. Weathering of sulfidic shale and copper mine waste: Secondary minerals and metal cycling in Great Smoky Mountains National Park, Tennessee, and North Carolina, USA

    USGS Publications Warehouse

    Hammarstrom, J.M.; Seal, R.R.; Meier, A.L.; Jackson, J.C.

    2003-01-01

    Metal cycling via physical and chemical weathering of discrete sources (copper mines) and regional (non-point) sources (sulfide-rich shale) is evaluated by examining the mineralogy and chemistry of weathering products in Great Smoky Mountains National Park, Tennessee, and North Carolina, USA. The elements in copper mine waste, secondary minerals, stream sediments, and waters that are most likely to have negative impacts on aquatic ecosystems are aluminum, copper, zinc, and arsenic because these elements locally exceed toxicity guidelines for surface waters or for stream sediments. Acid-mine drainage has not developed in streams draining inactive copper mines. Acid-rock drainage and chemical weathering processes that accompany debris flows or human disturbances of sulfidic rocks are comparable to processes that develop acid-mine drainage elsewhere. Despite the high rainfall in the mountain range, sheltered areas and intermittent dry spells provide local venues for development of secondary weathering products that can impact aquatic ecosystems.

  15. O-triple Isotopes of Primary and Secondary Minerals Provide Clues to the Past and Present Hydrosphere of Mars: New Experimental Evidence

    NASA Astrophysics Data System (ADS)

    Shaheen, R.; Thiemens, M. H.; Khachatryan, A.; Smirnova, V.; Jackson, T. L.

    2015-12-01

    Oxygen, the most abundant element in terrestrial planets link their lithospheres, hydrospheres and atmospheres, thus providing a powerful tool to fingerprint the physical and chemical processes involved in the exchange of material between these reservoirs (1). The oxygen triple isotopic composition of SNC Martian meteorites minerals provided a record of this unique interaction. Martian silicates showed an O-isotope anomaly (Δ17O = 0.4 ‰) unlike earth's silicate (Δ17O = 0‰). Additionally, there is a signficant variation in the oxygen isotopic composition of primary and secondary minerals both in the oldest (ALH84001: Δ17OCO3 = 0.7‰, Δ17Osilicates = 0.3‰)(2) and younger martian rocks (NWA7034: Δ17OCO3 = 0.0‰, Δ17Osilicates = 0.6‰)(3) indicating substantial changes in the global aqueous chemistry of Mars and its formation. These variations in oxygen isotope anomalies are important, but puzzling due to the lack of knoweldege of the intial conditions and relevant experiments. To understand the origin and nature of heterogeneity in the oxygen triple isotopes of various minerals, laboratory experiments were conducted by simulating current Martian conditions. Ozone, a martian atmospheric constituent, was used as a tracer to identify molecular reactions occurring on the mineral surfaces. The oxygen isotopic composition of decomposed ozone and water was measured following reaction over extended time under defined conditions . The decomposed O2 defines an array with a slope δ17O = 0.87 x δ18O + 5 (r2 = 0.99). The left over ozone after 18hours showed a decrease in slope (δ17O = 0.7 x δ18O + 5 (r2 = 0.97) and significant variations in Δ17O= 20 - 31‰ depending on the mineral used in the experiment. The slope did not pass through the initial ozone and water suggesting the formation of an intermediate species and its reaction and removal that is responsible for the exchange of O-isotopes between water-ozone and mineral oxides. These results coupled with

  16. Microstructural and microtextural characterization of oxide scale on steel using electron backscatter diffraction.

    PubMed

    Birosca, S; Dingley, D; Higginson, R L

    2004-03-01

    High-temperature oxidation of steel has been extensively studied. The microstructure of iron oxides is, however, not well understood because of the difficulty in imaging it using conventional methods, such as optical or electron microscopy. A knowledge of the oxide microstructure and texture is critical in understanding how the oxide film behaves during high-temperature deformation of steels and more importantly how it can be removed following processing. Recently, electron back-scatter diffraction (EBSD) has proved to be a powerful technique for distinguishing the different phases in scales. This technique gives valuable information both on the microstructure and on the orientation relationships between the steel and the scale layers. In the current study EBSD has been used to investigate the microstructure and microtexture of iron oxide layers grown on interstitial free steel at different times and temperatures. Heat treatments have been carried out under normal oxidation conditions in order to relate the results to real steel manufacturing in industry. The composition, morphologies, microstructure and microtexture of selected conditions have been studied using EBSD. PMID:15009690

  17. Microstructural and microtextural characterization of oxide scale on steel using electron backscatter diffraction.

    PubMed

    Birosca, S; Dingley, D; Higginson, R L

    2004-03-01

    High-temperature oxidation of steel has been extensively studied. The microstructure of iron oxides is, however, not well understood because of the difficulty in imaging it using conventional methods, such as optical or electron microscopy. A knowledge of the oxide microstructure and texture is critical in understanding how the oxide film behaves during high-temperature deformation of steels and more importantly how it can be removed following processing. Recently, electron back-scatter diffraction (EBSD) has proved to be a powerful technique for distinguishing the different phases in scales. This technique gives valuable information both on the microstructure and on the orientation relationships between the steel and the scale layers. In the current study EBSD has been used to investigate the microstructure and microtexture of iron oxide layers grown on interstitial free steel at different times and temperatures. Heat treatments have been carried out under normal oxidation conditions in order to relate the results to real steel manufacturing in industry. The composition, morphologies, microstructure and microtexture of selected conditions have been studied using EBSD.

  18. Geochemical, microtextural and petrological studies of the Samba prospect in the Zambian Copperbelt basement: a metamorphosed Palaeoproterozoic porphyry Cu deposit.

    NASA Astrophysics Data System (ADS)

    Master, Sharad; Mirrander Ndhlovu, N.

    2015-04-01

    Ever since Wakefield (1978, IMM Trans., B87, 43-52) described a porphyry-type meta-morphosed Cu prospect, the ca 50 Mt, 0.5% Cu Samba deposit (12.717°S, 27.833°E), hosted by porphyry-associated quartz-sericite-biotite schists in northern Zambia, there has been controversy about its origin and significance. This is because it is situated in the basement to the world's largest stratabound sediment-hosted copper province, the Central African Copperbelt, which is hosted by rocks of the Neoproterozoic Katanga Supergroup. Mineralization in the pre-Katangan basement has long played a prominent role in ore genetic models, with some authors suggesting that basement Cu mineralization may have been recycled into the Katangan basin through erosion and redeposition, while others have suggested that the circulation of fluids through Cu-rich basement may have leached out the metals which are found concentrated in the Katangan orebodies. On the basis of ca 490-460 Ma Ar-Ar ages, Hitzman et al. (2012, Sillitoe Vol., SEG Spec. Publ., 16, 487-514) suggested that Samba represents late-stage impregnation of copper mineralization into the basement, and that it was one of the youngest copper deposits known in the Central African Copperbelt. If the Samba deposit really is that young, then it would have post-dated regional deformation and metamorphism (560-510 Ma), and it ought to be undeformed and unmetamorphosed. The Samba mineralization consists of chalcopyrite and bornite, occurring as disseminations, stringers and veinlets, found in a zone >1 km along strike, in steeply-dipping lenses up to 10m thick and >150m deep. Our new major and trace element XRF geochemical data (14 samples) show that the host rocks are mainly calc-alkaline metadacites. Cu is correlated with Ag (Cu/Ag ~10,000:1) with no Au or Mo. Our study focused on the microtextures and petrology of the Samba ores. We confirm that there is alteration of similar style to that accompanying classical porphyry Cu mineralization

  19. Secondary sulfate minerals associated with acid drainage in the eastern US: Recycling of metals and acidity in surficial environments

    USGS Publications Warehouse

    Hammarstrom, J.M.; Seal, R.R.; Meier, A.L.; Kornfeld, J.M.

    2005-01-01

    Weathering of metal-sulfide minerals produces suites of variably soluble efflorescent sulfate salts at a number of localities in the eastern United States. The salts, which are present on mine wastes, tailings piles, and outcrops, include minerals that incorporate heavy metals in solid solution, primarily the highly soluble members of the melanterite, rozenite, epsomite, halotrichite, and copiapite groups. The minerals were identified by a combination of powder X-ray diffraction (XRD), scanning electron microscopy (SEM), and electron-microprobe. Base-metal salts are rare at these localities, and Cu, Zn, and Co are commonly sequestered as solid solutions within Fe- and Fe-Al sulfate minerals. Salt dissolution affects the surface-water chemistry at abandoned mines that exploited the massive sulfide deposits in the Vermont copper belt, the Mineral district of central Virginia, the Copper Basin (Ducktown) mining district of Tennessee, and where sulfide-bearing metamorphic rocks undisturbed by mining are exposed in Great Smoky Mountains National Park in North Carolina and Tennessee. Dissolution experiments on composite salt samples from three minesites and two outcrops of metamorphic rock showed that, in all cases, the pH of the leachates rapidly declined from 6.9 to 30 mg L-1), Fe (>47 mg L-1), sulfate (>1000 mg L-1), and base metals (>1000 mg L-1 for minesites, and 2 mg L-1 for other sites). Geochemical modeling of surface waters, mine-waste leachates, and salt leachates using PHREEQC software predicted saturation in the observed ochre minerals, but significant concentration by evaporation would be needed to reach saturation in most of the sulfate salts. Periodic surface-water monitoring at Vermont minesites indicated peak annual metal loads during spring runoff. At the Virginia site, where no winter-long snowpack develops, metal loads were highest during summer months when salts were dissolved periodically by rainstorms following sustained evaporation during dry

  20. Reaction path modelling used to explore the relationship between secondary mineral precipitation and low Si content in the meltwaters of a polythermal surge-type glacier

    NASA Astrophysics Data System (ADS)

    Crompton, J. W.; Flowers, G. E.; Kirste, D. M.; Hagedorn, B.

    2014-12-01

    The subglacial chemical weathering environment is characterized by low temperatures and the hydrolysis and carbonation of freshly comminuted mineral surfaces. Such conditions motivate the hypothesis that relatively low silica fluxes should be found in glacierized basins. Additionally, it is often assumed that glacier meltwaters are far from saturation and that the water chemistry is controlled solely by the dissolution of primary silicates and trace quantities of sulphide and carbonate minerals. Alternatively, we propose that the formation of secondary minerals and precipitates in the delayed drainage system play an important role in controlling the low silica fluxes observed in subglacial envrionments. Borehole and proglacial meltwater samples were collected from a polythermal surge-type glacier overlying granodiorite bedrock in the St. Elias Mountains of Yukon, Canada. The meltwater chemistry, along with the mineralogy of the bedrock and suspended sediments indicate the presence of mineral precipitation accompanied by substantial basal freeze-on. This is supported by field evidence of debris rich basal ice at the terminus and at the base of a borehole. The surplus of Cl- above the supraglacial input is used to calculate the amount of basal freeze-on in the delayed drainage system, and the amount of mixing between the delayed and fast drainage systems. We use Geochemist's Workbench for reaction path modelling with a focus on the silica composition to simulate the chemical evolution of glacial meltwater from (1) the initial water rock contact, (2) basal freeze on, and (3) mixing and post mixing reactions. Unless there is a substantial degree of non-stoichiometric dissolution, we find that the observed proglacial water chemistry at the terminus is largely controlled by the hydrochemistry of water in the delayed drainage system. Lastly, we use this model to explore the relationship between the proglacial water chemistry and the daily glacier surface velocities for

  1. Shock-thermal history of Kavarpura IVA iron: Evidences from microtextures and nickel profiling

    NASA Astrophysics Data System (ADS)

    Ray, Dwijesh; Ghosh, S.; Murty, S. V. S.

    2015-11-01

    We classify Kavarpura iron (fell in August, 2006, in Rajasthan, India), an inclusion-free member of high-Ni IVA group. Widmanstätten pattern and finger-cellular plessites textures characteristic of IVA group are present in Kavarpura. Symmetric and asymmetric textural zoning within the cloudy taenite and plessite refer to long term martensitisation process with mean metallographic cooling rate of 200 °C/Ma. Imprints of variable shock pressure domains (Neumann bands and shock hatched ε kamacite) suggest alteration by up to 600 kb shock pressure. Degeneration of cellular plessites, bending of finger plessites and plastic flowage of taenites bear textural evidences corresponding to post-shock annealing which is further confirmed by Ni profiles across the cloudy taenites and plessites under high shock pressure domains. Based on microtextural evidences and Ni profiling, we suggest Kavarpura had cooled at steady state and subsequently suffered multiple impacts.

  2. Microtexture and Nanoindentation Study of Delamination Cracking in Al-Cu-Li-X Alloys

    NASA Technical Reports Server (NTRS)

    Crooks, R.; Domack, M. S.; Wagner, J. A.

    2005-01-01

    Commercial Al-Li alloys have strength and weight advantages over non-Li aluminum alloys. The fracture behavior of these alloys is unusual and has limited their use. The fracture mode, described as delamination, is intergranular, along the broad grain boundaries parallel to the rolling plane of the plate. Microtexture analyses have shown that delaminations occur along boundaries with greater than 30 misorientation. However, it was observed that relatively few of the high angle boundaries exhibited this behavior. Some grains of the retained deformation texture show high internal misorientation, which is a measure of stored strain energy. Delamination tends to occur between these grains and adjacent, recrystallized grains. Nanoindentation studies indicate a higher hardness for the high internal misorientation grains. These results suggest that the delamination could be reduced by processing the alloys to minimize grain-to-grain property disparities.

  3. Effects of oxyanions, natural organic matter, and bacterial cell numbers on the bioreduction of lepidocrocite ({gamma}-FeOOH) and the formation of secondary mineralization products.

    SciTech Connect

    O'Loughlin, E. J.; Gorski, C. A.; Scherer, M. M.; Boyanov, M. I.; Kemner, K. M.; Biosciences Division; Univ. of Iowa

    2010-06-15

    Microbial reduction of Fe(III) oxides results in the production of Fe(II) and may lead to the subsequent formation of Fe(II)-bearing secondary mineralization products including magnetite, siderite, vivianite, chukanovite (ferrous hydroxy carbonate (FHC)), and green rust; however, the factors controlling the formation of specific Fe(II) phases are often not well-defined. This study examined effects of (i) a range of inorganic oxyanions (arsenate, borate, molybdate, phosphate, silicate, and tungstate), (ii) natural organic matter (citrate, oxalate, microbial extracellular polymeric substances [EPS], and humic substances), and (iii) the type and number of dissimilatory iron-reducing bacteria on the bioreduction of lepidocrocite and formation of Fe(II)-bearing secondary mineralization products. The bioreduction kinetics clustered into two distinct Fe(II) production profiles. 'Fast' Fe(II) production kinetics [19-24 mM Fe(II) d-1] were accompanied by formation of magnetite and FHC in the unamended control and in systems amended with borate, oxalate, gellan EPS, or Pony Lake fulvic acid or having 'low' cell numbers. Systems amended with arsenate, citrate, molybdate, phosphate, silicate, tungstate, EPS from Shewanella putrefaciens CN32, or humic substances derived from terrestrial plant material or with 'high' cell numbers exhibited comparatively slow Fe(II) production kinetics [1.8-4.0 mM Fe(II) d-1] and the formation of green rust. The results are consistent with a conceptual model whereby competitive sorption of more strongly bound anions blocks access of bacterial cells and reduced electron-shuttling compounds to sites on the iron oxide surface, thereby limiting the rate of bioreduction.

  4. Effects of oxyanions, natural organic matter, and bacterial cell numbers on the bioreduction of lepidocrocite (gamma-FeOOH) and the formation of secondary mineralization products.

    PubMed

    O'Loughlin, Edward J; Gorski, Christopher A; Scherer, Michelle M; Boyanov, Maxim I; Kemner, Kenneth M

    2010-06-15

    Microbial reduction of Fe(III) oxides results in the production of Fe(II) and may lead to the subsequent formation of Fe(II)-bearing secondary mineralization products including magnetite, siderite, vivianite, chukanovite (ferrous hydroxy carbonate (FHC)), and green rust; however, the factors controlling the formation of specific Fe(II) phases are often not well-defined. This study examined effects of (i) a range of inorganic oxyanions (arsenate, borate, molybdate, phosphate, silicate, and tungstate), (ii) natural organic matter (citrate, oxalate, microbial extracellular polymeric substances [EPS], and humic substances), and (iii) the type and number of dissimilatory iron-reducing bacteria on the bioreduction of lepidocrocite and formation of Fe(II)-bearing secondary mineralization products. The bioreduction kinetics clustered into two distinct Fe(II) production profiles. "Fast" Fe(II) production kinetics [19-24 mM Fe(II) d(-1)] were accompanied by formation of magnetite and FHC in the unamended control and in systems amended with borate, oxalate, gellan EPS, or Pony Lake fulvic acid or having "low" cell numbers. Systems amended with arsenate, citrate, molybdate, phosphate, silicate, tungstate, EPS from Shewanella putrefaciens CN32, or humic substances derived from terrestrial plant material or with "high" cell numbers exhibited comparatively slow Fe(II) production kinetics [1.8-4.0 mM Fe(II) d(-1)] and the formation of green rust. The results are consistent with a conceptual model whereby competitive sorption of more strongly bound anions blocks access of bacterial cells and reduced electron-shuttling compounds to sites on the iron oxide surface, thereby limiting the rate of bioreduction. PMID:20476735

  5. Effects of oxyanions, natural organic matter, and bacterial cell numbers on the bioreduction of lepidocrocite (gamma-FeOOH) and the formation of secondary mineralization products.

    PubMed

    O'Loughlin, Edward J; Gorski, Christopher A; Scherer, Michelle M; Boyanov, Maxim I; Kemner, Kenneth M

    2010-06-15

    Microbial reduction of Fe(III) oxides results in the production of Fe(II) and may lead to the subsequent formation of Fe(II)-bearing secondary mineralization products including magnetite, siderite, vivianite, chukanovite (ferrous hydroxy carbonate (FHC)), and green rust; however, the factors controlling the formation of specific Fe(II) phases are often not well-defined. This study examined effects of (i) a range of inorganic oxyanions (arsenate, borate, molybdate, phosphate, silicate, and tungstate), (ii) natural organic matter (citrate, oxalate, microbial extracellular polymeric substances [EPS], and humic substances), and (iii) the type and number of dissimilatory iron-reducing bacteria on the bioreduction of lepidocrocite and formation of Fe(II)-bearing secondary mineralization products. The bioreduction kinetics clustered into two distinct Fe(II) production profiles. "Fast" Fe(II) production kinetics [19-24 mM Fe(II) d(-1)] were accompanied by formation of magnetite and FHC in the unamended control and in systems amended with borate, oxalate, gellan EPS, or Pony Lake fulvic acid or having "low" cell numbers. Systems amended with arsenate, citrate, molybdate, phosphate, silicate, tungstate, EPS from Shewanella putrefaciens CN32, or humic substances derived from terrestrial plant material or with "high" cell numbers exhibited comparatively slow Fe(II) production kinetics [1.8-4.0 mM Fe(II) d(-1)] and the formation of green rust. The results are consistent with a conceptual model whereby competitive sorption of more strongly bound anions blocks access of bacterial cells and reduced electron-shuttling compounds to sites on the iron oxide surface, thereby limiting the rate of bioreduction.

  6. DOE FG02-03ER63557: Final Technical Report: Reactivity of Primary Soil Minerals and Secondary Precipitates Beneath Leaking Hanford Waste Tanks

    SciTech Connect

    Kathryn L. Nagy

    2009-05-04

    The purpose of the project was to investigate rates and mechanisms of reactions between primary sediment minerals and key components of waste tank solutions that leaked into the subsurface at the Hanford Site. Results were expected to enhance understanding of processes that cause (1) changes in porosity and permeability of the sediment and resultant changes in flow paths of the contaminant plumes, (2) formation of secondary precipitates that can take up contaminants in their structures, and (3) release of mineral components that can drive redox reactions affecting dissolved contaminant mobility. Measured rates can also be used directly in reactive transport models. Project tasks included (1) measurement of the dissolution rates of biotite mica from low to high pH and over a range of temperature relevant to the Hanford subsurface, (2) measurement of dissolution rates of quartz at high pH and in the presence of dissolved alumina, (3) measurement of the dissolution rates of plagioclase feldspar in high pH, high nitrate, high Al-bearing solutions characteristic of the BX tank farms, (4) incorporation of perrhenate in iron-oxide minerals as a function of pH, and (5) initiation of experiments to measure the formation of uranium(VI)-silicate phases under ambient conditions. Task 2 was started under a previous grant from the Environmental Management Science Program and Task 4 was partially supported by a grant to the PI from the Geosciences Program, Office of Basic Energy Sciences. Task 5 was continued under a subsequent grant from the Environmental Remediation Sciences Program, Office of Biological and Environmental Research.

  7. Spectral reflectance properties (0.4-2.5 μm) of secondary Fe-oxide, Fe-hydroxide, and Fe-sulphate-hydrate minerals associated with sulphide-bearing mine wastes

    USGS Publications Warehouse

    Crowley, J.K.; Williams, D.E.; Hammarstrom, J.M.; Piatak, N.; Chou, I.-Ming; Mars, J.C.

    2003-01-01

    Diffuse reflectance spectra of 15 mineral species commonly associated with sulphide-bearing mine wastes show diagnostic absorption bands related to electronic processes involving ferric and/or ferrous iron, and to vibrational processes involving water and hydroxyl. Many of these absorption bands are relatively broad and overlapping; however, spectral analysis methods, including continuum removal and derivative analysis, permit most of the minerals to be distinguished. Key spectral differences between the minerals are illustrated in a series of plots showing major absorption band centres and other spectral feature positions. Because secondary iron minerals are sensitive indicators of pH, Eh, relative humidity, and other environmental conditions, spectral mapping of mineral distributions promises to have important application to mine waste remediation studies.

  8. Spectral reflectance properties (0.4-2.5 um) of secondary Fe-oxide, Fe-hydroxide, and Fe-sulfate-hydrate minerals associated with sulfide-bearing mine waste

    USGS Publications Warehouse

    Crowley, J.K.; Williams, D.E.; Hammarstrom1, J.M.; Piatak, N.; Mars, J.C.; Chou, I-Ming

    2006-01-01

    Fifteen Fe-oxide, Fe-hydroxide, and Fe-sulphate-hydrate mineral species commonly associated with sulphide bearing mine wastes were characterized by using X-ray powder diffraction and scanning electron microscope methods. Diffuse reflectance spectra of the samples show diagnostic absorption features related to electronic processes involving ferric and/or ferrous iron, and to vibrational processes involving water and hydroxyl ions. Such spectral features enable field and remote sensing based studies of the mineral distributions. Because secondary minerals are sensitive indicators of pH, Eh, relative humidity, and other environmental conditions, spectral mapping of these minerals promises to have important applications to mine waste remediation studies. This report releases digital (ascii) spectra (spectral_data_files.zip) of the fifteen mineral samples to facilitate usage of the data with spectral libraries and spectral analysis software. The spectral data are provided in a two-column format listing wavelength (in micrometers) and reflectance, respectively.

  9. Chemometric evaluation of time-of-flight secondary ion mass spectrometry data of minerals in the frame of future in situ analyses of cometary material by COSIMA onboard ROSETTA.

    PubMed

    Engrand, Cecile; Kissel, Jochen; Krueger, Franz R; Martin, Philippe; Silén, Johan; Thirkell, Laurent; Thomas, Roger; Varmuza, Kurt

    2006-01-01

    Chemometric data evaluation methods for time-of-flight secondary ion mass spectrometry (TOF-SIMS) have been tested for the characterization and classification of minerals. Potential applications of these methods include the expected data from cometary material to be measured by the COSIMA instrument onboard the ESA mission ROSETTA in the year 2014. Samples of the minerals serpentine, enstatite, olivine, and talc have been used as proxies for minerals existing in extraterrestrial matter. High mass resolution TOF-SIMS data allow the selection of peaks from inorganic ions relevant for minerals. Multivariate cluster analysis of peak intensity data by principal components analysis and the new method CORICO showed a good separation of the mineral classes. Classification by k nearest-neighbor classification (KNN) or binary decision trees (CART method) results in more than 90% correct class assignments in a leave-one-out cross validation.

  10. Radioactive Bench-scale Steam Reformer Demonstration of a Monolithic Steam Reformed Mineralized Waste Form for Hanford Waste Treatment Plant Secondary Waste - 12306

    SciTech Connect

    Evans, Brent; Olson, Arlin; Mason, J. Bradley; Ryan, Kevin; Jantzen, Carol; Crawford, Charles

    2012-07-01

    Hanford currently has 212,000 m{sup 3} (56 million gallons) of highly radioactive mixed waste stored in the Hanford tank farm. This waste will be processed to produce both high-level and low-level activity fractions, both of which are to be vitrified. Supplemental treatment options have been under evaluation for treating portions of the low-activity waste, as well as the liquid secondary waste from the low-activity waste vitrification process. One technology under consideration has been the THOR{sup R} fluidized bed steam reforming process offered by THOR Treatment Technologies, LLC (TTT). As a follow-on effort to TTT's 2008 pilot plant FBSR non-radioactive demonstration for treating low-activity waste and waste treatment plant secondary waste, TTT, in conjunction with Savannah River National Laboratory, has completed a bench scale evaluation of this same technology on a chemically adjusted radioactive surrogate of Hanford's waste treatment plant secondary waste stream. This test generated a granular product that was subsequently formed into monoliths, using a geo-polymer as the binding agent, that were subjected to compressibility testing, the Product Consistency Test and other leachability tests, and chemical composition analyses. This testing has demonstrated that the mineralized waste form, produced by co-processing waste with kaolin clay using the TTT process, is as durable as low-activity waste glass. Testing has shown the resulting monolith waste form is durable, leach resistant, and chemically stable, and has the added benefit of capturing and retaining the majority of Tc-99, I-129, and other target species at high levels. (authors)

  11. Wetting state on hydrophilic and hydrophobic micro-textured surfaces: Thermodynamic analysis and X-ray visualization

    SciTech Connect

    Yu, Dong In; Kwak, Ho Jae; Doh, Seung Woo; Park, Hyun Sun Kiyofumi, Moriyama; Kang, Hie Chan; Ahn, Ho Seon; Kim, Moo Hwan

    2015-04-27

    In this study, the wetting state on hydrophobic and hydrophilic micro-textured surfaces was investigated. High spatial resolution synchrotron X-ray radiography was used to overcome the limitations in visualization in previous research and clearly visualize the wetting state for each droplet under quantified surface conditions. Based on thermodynamic characteristics, a theoretical model for wetting state depending on the chemical composition (intrinsic contact angle) and geometrical morphology (roughness ratio) of the surfaces was developed.

  12. Response of bone marrow derived connective tissue progenitor cell morphology and proliferation on geometrically modulated microtextured substrates

    PubMed Central

    Kim, Eun Jung; Fleischman, Aaron J.; Muschler, George F.; Roy, Shuvo

    2013-01-01

    Varying geometry and layout of microposts on a cell culture substrate provides an effective technique for applying mechanical stimuli to living cells. In the current study, the optimal geometry and arrangement of microposts on the polydimethylsiloxane (PDMS) surfaces to enhance cell growth behavior were investigated. Human bone marrow derived connective tissue progenitor cells were cultured on PDMS substrates comprising unpatterned smooth surfaces and cylindrical post microtextures that were 10 µm in diameter, 4 heights (5, 10, 20 and 40 µm) and 3 pitches (10, 20, and 40 µm). With the same 10 µm diameter, post heights ranging from 5 to 40 µm resulted in a more than 535000 fold range of rigidity from 0.011 nNµm−1 (40 µm height) up to 5888 nNµm−1(5 µm height). Even though shorter microposts result in higher effective stiffness, decreasing post heights below the optimal value, 5 µm height micropost in this study decreased cell growth behavior. The maximum number of cells was observed on the post microtextures with 20 µm height and 10 µm inter-space, which exhibited a 675% increase relative to the smooth surfaces. The cells on all heights of post microtextures with 10 µm and 20 µm inter-spaces exhibited highly contoured morphology. Elucidating the cellular response to various external geometry cues enables us to better predict and control cellular behavior. In addition, knowledge of cell response to surface stimuli could lead to the incorporation of specific size post microtextures into surfaces of implants to achieve surface-textured scaffold materials for tissue engineering applications. PMID:23378044

  13. Does the Laser-Microtextured Short Implant Collar Design Reduce Marginal Bone Loss in Comparison with a Machined Collar?

    PubMed Central

    Sirali, Ali; Gultekin, Pinar; Yalcin, Serdar; Mijiritsky, Eitan

    2016-01-01

    Purpose. To compare marginal bone loss between subgingivally placed short-collar implants with machined collars and those with machined and laser-microtextured collars. Materials and Methods. The investigators used a retrospective study design and included patients who needed missing posterior teeth replaced with implants. Short-collar implants with identical geometries were divided into two groups: an M group, machined collar; and an L group, machined and laser-microtextured collar. Implants were evaluated according to marginal bone loss, implant success, and probing depth (PD) at 3 years of follow-up. Results. Sixty-two patients received 103 implants (56 in the M group and 47 in the L group). The cumulative survival rate was 100%. All implants showed clinically acceptable marginal bone loss, although bone resorption was lower in the L group (0.49 mm) than in the M group (1.38 mm) at 3 years (p < 0.01). A significantly shallower PD was found for the implants in the L group during follow-up (p < 0.01). Conclusions. Our results suggest predictable outcomes with regard to bone loss for both groups; however, bone resorption was less in the L group than in the M group before and after loading. The laser-microtextured collar implant may provide a shallower PD than the machined collar implant. PMID:27660765

  14. Does the Laser-Microtextured Short Implant Collar Design Reduce Marginal Bone Loss in Comparison with a Machined Collar?

    PubMed Central

    Sirali, Ali; Gultekin, Pinar; Yalcin, Serdar; Mijiritsky, Eitan

    2016-01-01

    Purpose. To compare marginal bone loss between subgingivally placed short-collar implants with machined collars and those with machined and laser-microtextured collars. Materials and Methods. The investigators used a retrospective study design and included patients who needed missing posterior teeth replaced with implants. Short-collar implants with identical geometries were divided into two groups: an M group, machined collar; and an L group, machined and laser-microtextured collar. Implants were evaluated according to marginal bone loss, implant success, and probing depth (PD) at 3 years of follow-up. Results. Sixty-two patients received 103 implants (56 in the M group and 47 in the L group). The cumulative survival rate was 100%. All implants showed clinically acceptable marginal bone loss, although bone resorption was lower in the L group (0.49 mm) than in the M group (1.38 mm) at 3 years (p < 0.01). A significantly shallower PD was found for the implants in the L group during follow-up (p < 0.01). Conclusions. Our results suggest predictable outcomes with regard to bone loss for both groups; however, bone resorption was less in the L group than in the M group before and after loading. The laser-microtextured collar implant may provide a shallower PD than the machined collar implant.

  15. Nanotexturing process on microtextured surfaces of silicon solar cells by SF6/O2 reactive ion etching.

    PubMed

    Ji, Hyungyong; Choi, Jaeho; Lim, Gyoungho; Parida, Bhaskar; Kim, Keunjoo; Jo, Jung Hee; Kim, Hong Seub

    2013-12-01

    We investigated a nanotexturing process on the microtextured surface of single crystalline silicon solar cell by the reactive ion etching process in SF6/O2 mixed gas ambient. P-type Si wafer samples were prepared using a chemical wet etching process to address saw damage removal and achieve microtexturing. The microtextured wafers were further processed for nanotexturing by exposure to reactive ions within a circular tray of wafer carrier containing many small holes for uniform etching. As the dry etching times were increased to 2, 4 and finally to 8 min, surface structures were observed in a transition from nanoholes to nanorods, and a variation in wafer color from dark blue to black. The surface nanostructures showed a lowered photoreflectance and enhanced quantum efficiency within the visible light region with wavelengths of less than 679 nm. The nanohole structure etched for 2 min showed enhanced conversion efficiency when compared to the bare sample; however, the nanorod structure etched for 8 min exhibited the decreased efficiency with a reduced short circuit current, indicating that the surface nanostructural damage with the enlarged nanoperimetric surface area is sensitive to surface passivation from the surface recombination process.

  16. Lower fibroblast growth factor 23 levels in young adults with Crohn disease as a possible secondary compensatory effect on the disturbance of bone and mineral metabolism.

    PubMed

    Oikonomou, Konstantinos A; Orfanidou, Timoklia I; Vlychou, Marianna K; Kapsoritakis, Andreas N; Tsezou, Aspasia; Malizos, Konstantinos N; Potamianos, Spyros P

    2014-01-01

    Fibroblast growth factor 23 (FGF-23) is a bone-derived circulating phosphaturic factor that decreases serum concentration of phosphate and vitamin D, suggested to actively participate in a complex renal-gastrointestinal-skeletal axis. Serum FGF-23 concentrations, as well as various other laboratory parameters involved in bone homeostasis, were measured and analyzed with regard to various diseases and patients' characteristics in 44 patients with Crohn disease (CD) and 20 healthy controls (HCs) included in this cross-sectional study. Serum FGF-23 levels were significantly lower in patients with CD (900.42 ± 815.85pg/mL) compared with HC (1410.94 ± 1000.53pg/mL), p = 0.037. Further analyses suggested FGF-23 as a factor independent from various parameters including age (r = -0.218), body mass index (r = -0.115), 25-hydroxy vitamin D (r = 0.126), parathyroid hormone (r = 0.084), and bone mineral density (BMD) of hip and lumbar (r = 0.205 and r = 0.149, respectively). This observation remained even after multivariate analyses, exhibiting that BMD was not affected by FGF-23, although parameters such as age (p = 0.026), cumulative prednisolone dose (p < 0.0001), and smoking status (p = 0.024) were strong determinants of BMD regarding hip. Lower FGF-23 levels in patients with bowel inflammation are accompanied but not directly correlated with lower vitamin D levels, showing no impact on BMD determination of young adults with CD. The downregulation of serum FGF-23 levels in CD appears as a secondary compensatory effect on the bone and mineral metabolism induced by chronic intestinal inflammation.

  17. Microtextured metals for stray-light suppression in the Clementine startracker

    NASA Technical Reports Server (NTRS)

    Johnson, E. A.

    1993-01-01

    Anodized blacks for suppressing stray light in optical systems can now be replaced by microscopically textured metal surfaces. An application of these black surfaces to the Clementine star-tracker navigational system, which will be launched in early 1994 to examine the Moon, en route to intercept an asteroid, is detailed. Rugged black surfaces with Lambertian BRDF less than 10(exp -2) srad(sup -1) are critical for suppressing stray light in the star-tracker optical train. Previously available materials spall under launch vibrations to contaminate mirrors and lenses. Microtextured aluminum is nearly as dark, but much less fragile. It is made by differential ion beam sputtering, which generates light-trapping pores and cones slightly smaller than the wavelength to be absorbed. This leaves a sturdy but light-absorbing surface that can survive challenging conditions without generating debris or contaminants. Both seeded ion beams and plasma immersion (from ECR plasmas) extraction can produce these microscopic textures without fragile interfaces. Process parameters control feature size, spacing, and optical effects (THR, BRDF). Both broad and narrow absorption bands can be engineered with tuning for specific wavelengths and applications. Examples are presented characterized by FTIR in reflection librators (0.95 normal emissivity), heat rejection, and enhanced nucleate boiling.

  18. Numerical modelling of microdroplet self-propelled jumping on micro-textured surface

    NASA Astrophysics Data System (ADS)

    Attarzadeh, S. M. Reza; Dolatabadi, Ali; Chun Kim, Kyung

    2015-11-01

    Understanding various stages of single and multiple droplet impact on a super-hydrophobic surface is of interest for many industrial applications such as aerospace industry. In this study, the phenomenon of coalescence induced droplets self-propelled jumping on a micro-textured super-hydrophobic surface is numerically simulated using Volume of Fluid (VOF) method. This model mimics the scenario of coalescing cloud-sized particles over the surface structure of an aircraft. The VOF coupled with a dynamic contact angle model is used to simulate the coalescence of two equal size droplets, that are initially placed very closed to each other with their interface overlapping with each other's which triggers the incipience of their coalescence. The textured surface is modeled as a series of equally spaced squared pillars, with 111° as the intrinsic contact angle all over the solid contact area. It is shown that the radial velocity of coalescing liquid bridge is reverted to upward direction due to the counter action of the surface to the basal area of droplet in contact. The presence of air beneath the droplet inside micro grooves which aimed at repelling water droplet is also captured in this model. The simulated results are found in good agreement with experimental observations. The authors gratefully acknowledge the financial support from Natural Sciences and Engineering Research Council of Canada (NSERC), Consortium de Recherche et d'innovation en Aerospatiale au Quebec (CRIAQ), Bombardier Aerospace, Pratt Whitney Canada.

  19. Wetting behaviour of laser synthetic surface microtextures on Ti-6Al-4V for bioapplication.

    PubMed

    Dahotre, Narendra B; Paital, Sameer R; Samant, Anoop N; Daniel, Claus

    2010-04-28

    Wettability at the surface of an implant material plays a key role in its success as it modulates the protein adsorption and thereby influences cell attachment and tissue integration at the interface. Hence, surface engineering of implantable materials to enhance wettability to physiological fluid under in vivo conditions is an area of active research. In light of this, in the present work, laser-based optical interference and direct melting techniques were used to develop synthetic microtextures on Ti-6Al-4V alloys, and their effects on wettability were studied systematically. Improved wettability to simulated body fluid and distilled water was observed for Ca-P coatings obtained by direct melting technique. This superior wettability was attributed to both the appropriate surface chemistry and the three-dimensional surface features obtained using this technique. To assert a better control on surface texture and wettability, a three-dimensional thermal model based on COMSOL's multiphysics was employed to predict the features obtained by laser melting technique. The effect of physical texture and wetting on biocompatibility of laser-processed Ca-P coatings was evaluated in the preliminary efforts on culturing of mouse MC3T3-E1 osteoblast cells.

  20. Metal nanoparticle-enhanced photocurrent in GaAs photovoltaic structures with microtextured interfaces.

    PubMed

    Dmitruk, Nicolas L; Borkovskaya, Olga Yu; Mamontova, Iryna B; Mamykin, Sergii V; Malynych, Sergii Z; Romanyuk, Volodymyr R

    2015-01-01

    The photocurrent enhancement effect caused by Au and Ag nanoparticles for GaAs-based photovoltaic structures of surface barrier or p-n junction type with microtextured interfaces has been investigated in dependence on the conditions of nanoparticles deposition and, respectively, on the shape and local dielectric environment of obtained nanoparticle arrays. Three nanoparticle deposition methods have been checked: 1) photoinduced chemical deposition of Au from aqueous AuCl3 solution forming nanowires on the ridges of quasigrating-type surface microrelief, 2) deposition of Ag nanoparticles from colloidal suspension on the GaAs substrate covered with poly(vinylpyridine), and 3) drop and dry deposition of Au/SiO2 core-shell nanoparticles from aqueous colloid solution. The comprehensive investigation of optical reflectance, photoelectric, and electrical characteristics of the fabricated barrier structures has shown the highest photovoltaic parameters for surface microrelief of quasigrating-type and electroless Au nanoparticle deposition. The analysis of characteristics obtained allowed us also to define the mechanisms of the total photocurrent enhancement. PMID:25852368

  1. RADIOACTIVE DEMONSTRATION OF FINAL MINERALIZED WASTE FORMS FOR HANFORD WASTE TREATMENT PLANT SECONDARY WASTE BY FLUIDIZED BED STEAM REFORMING USING THE BENCH SCALE REFORMER PLATFORM

    SciTech Connect

    Crawford, C.; Burket, P.; Cozzi, A.; Daniel, W.; Jantzen, C.; Missimer, D.

    2012-02-02

    (mineral) waste form. The mineral waste form that is produced by co-processing waste with kaolin clay in an FBSR process has been shown to be as durable as LAW glass. Monolithing of the granular FBSR product is being investigated to prevent dispersion during transport or burial/storage, but is not necessary for performance. A Benchscale Steam Reformer (BSR) was designed and constructed at the SRNL to treat actual radioactive wastes to confirm the findings of the non-radioactive FBSR pilot scale tests and to qualify the waste form for applications at Hanford. BSR testing with WTP SW waste surrogates and associated analytical analyses and tests of granular products (GP) and monoliths began in the Fall of 2009, and then was continued from the Fall of 2010 through the Spring of 2011. Radioactive testing commenced in 2010 with a demonstration of Hanford's WTP-SW where Savannah River Site (SRS) High Level Waste (HLW) secondary waste from the Defense Waste Processing Facility (DWPF) was shimmed with a mixture of {sup 125/129}I and {sup 99}Tc to chemically resemble WTP-SW. Prior to these radioactive feed tests, non-radioactive simulants were also processed. Ninety six grams of radioactive granular product were made for testing and comparison to the non-radioactive pilot scale tests. The same mineral phases were found in the radioactive and non-radioactive testing.

  2. Pan-Spectral Analysis of Classic Martian Low-Albedo Regions: Updates on the Nature and Distribution of Primary and Secondary Mineral Phases

    NASA Astrophysics Data System (ADS)

    Salvatore, M. R.; Mustard, J. F.; Head, J. W.; Rogers, D.

    2013-12-01

    In this study, we investigate the primary and secondary mineralogy of martian low-albedo regions using a combination of visible/near-infrared (VNIR) reflectance and thermal infrared (TIR) emission datasets. TIR data were originally derived using the Thermal Emission Spectrometer (TES) instrument by [1,2], who interpreted these low-albedo regions to contain variable amounts of both basaltic and high-silica components; however, the nature of these high-silica phases remains uncertain, and both primary (e.g., volcanic glass) and secondary (e.g., hydrated alteration minerals) origins have been proposed. The mineralogical signatures of the evolving martian geologic, hydrologic, and climatic systems are recorded in these low-albedo regions, making the characterization of the identified high-silica phases critical towards better understanding the history of Mars. Consequently, we have completed a pan-spectral (VNIR and TIR) investigation of the nine low-albedo regions characterized by [2] in order to further constrain the composition of these martian landscapes. We derived regional VNIR spectra using Observatoire pour la Minéralogie, l'Eau, les Glaces, et l'Activité (OMEGA) data. Data were acquired, processed, atmospherically corrected, and weighted based on their relative areal contributions, resulting in nine representative regional spectra. The primary mineral phases identified in VNIR spectra are consistent with a dominantly basaltic composition and are in good agreement with previous TIR analyses. The variability in the shape and position of the broad 2 micron crystal field absorption feature, classically attributed to variations in pyroxene composition, is quantitatively assessed using modified Gaussian modeling (MGM) approaches. The position of this 2 micron band, though, can also be influenced by oxidative weathering processes like those identified in Antarctica, which result in more negative spectral slopes in the near-infrared as well as apparent shifts of the

  3. Micro-textures and in situ sulfur isotopic analysis of spheroidal and zonal sulfides in the giant Jinding Zn-Pb deposit, Yunnan, China: Implications for biogenic processes

    NASA Astrophysics Data System (ADS)

    Xue, Chunji; Chi, Guoxiang; Fayek, Mostafa

    2015-05-01

    The Jinding deposit in Yunnan, southwest China, is the largest sandstone- and conglomerate-hosted Zn-Pb deposit in the world. In this paper, we report various micro-textures of spheroidal and zonal sulfides, such as pellet-shaped and colloform aggregates of pyrite and sphalerite, from the deposit and interpret them to be possibly related to micro-colonies of sulfate reducing bacteria, probably supporting an in situ BSR hypothesis. Micro-scale sulfur isotope analysis in different parts of the spheroidal and zonal sulfide aggregates, using secondary ion mass spectrometry (SIMS), revealed δ34S (VCDT) values as low as -48.4‰ for sulfides formed in the early-main stage disseminated ores in the western part of the deposit, possibly suggesting maximum sulfur isotopic fractionation through BSR. Relatively elevated δ34S (VCDT) values (-7.7‰ to -34.8‰, mainly from -10‰ to -20‰) for the late-stage, cavity-filling ores in the eastern part of the deposit, are interpreted to be possibly related to elevated temperatures close to the hydrothermal conduit and elevated δ34S values of the remaining sulfates resulting from the preceding BSR processes. The apparent discrepancy between the low temperatures required for BSR and the high temperatures indicated by fluid inclusions (>120 °C) may be reconciled through invoking episodic influx of ore-forming hydrothermal fluids into a shallow, relatively cool environment. It is proposed that the host rocks of the Jinding deposit have not been buried to great depths (⩽1 km), which, combined with the availability of hydrocarbons in the Jinding dome (a paleo-oil and gas reservoir), provides an ideal environment for BSR. Episodic influx of metal-carrying hydrothermal fluids temporarily and locally suppressed BSR and promoted thermo-chemical sulfate reduction (TSR), resulting in deposit- and micro-scale variations of δ34S.

  4. Metal-like conductivity exhibited by triboelectrically deposited polyaniline (emeraldine base) particles on microtextured SiC surfaces

    NASA Astrophysics Data System (ADS)

    Bayer, I. S.; Caramia, V.; Biswas, A.; Cingolani, R.; Athanassiou, A.

    2012-05-01

    We demonstrate a simple and rapid way to deposit layers of polyaniline (emeraldine base) particles on flexible microtextured silicon carbide surfaces by contact charging them using a smooth dielectric rubber. Wetting of the layers by trifluoroacetic acid creates conductive, continuous polymeric films after drying. Pre-functionalization of the textured surfaces with anionic surfactants prevents particle coagulation during contact charging and decreases sheet resistance to metal-like levels (˜60 Ω/□). Conductivity of the films can be tuned by controlling the rate of acid evaporation. Conductive films are highly stable under ambient conditions and show no hysteresis when biased with zero delay-time.

  5. Natural radionuclide mobility and its influence on U-Th-Pb dating of secondary minerals from the unsaturated zone at Yucca Mountain, Nevada

    USGS Publications Warehouse

    Neymark, L.A.; Amelin, Y.V.

    2008-01-01

    Extreme U and Pb isotope variations produced by disequilibrium in decay chains of 238U and 232Th are found in calcite, opal/chalcedony, and Mn-oxides occurring as secondary mineral coatings in the unsaturated zone at Yucca Mountain, Nevada. These very slowly growing minerals (mm my-1) contain excess 206Pb and 208Pb formed from excesses of intermediate daughter isotopes and cannot be used as reliable 206Pb/238U geochronometers. The presence of excess intermediate daughter isotopes does not appreciably affect 207Pb/235U ages of U-enriched opal/chalcedony, which are interpreted as mineral formation ages. Opal and calcite from outer (younger) portions of coatings have 230Th/U ages from 94.6 ?? 3.7 to 361.3 ?? 9.8 ka and initial 234U/238U activity ratios (AR) from 4.351 ?? 0.070 to 7.02 ?? 0.12, which indicate 234U enrichment from percolating water. Present-day 234U/238U AR is ???1 in opal/chalcedony from older portions of the coatings. The 207Pb/235U ages of opal/chalcedony samples range from 0.1329 ?? 0.0080 to 9.10 ?? 0.21 Ma, increase with microstratigraphic depth, and define slow long-term average growth rates of about 1.2-2.0 mm my-1, in good agreement with previous results. Measured 234U/238U AR in Mn-oxides, which pre-date the oldest calcite and opal/chalcedony, range from 0.939 ?? 0.006 to 2.091 ?? 0.006 and are >1 in most samples. The range of 87Sr/86Sr ratios (0.71156-0.71280) in Mn-oxides overlaps that in the late calcite. These data indicate that Mn-oxides exchange U and Sr with percolating water and cannot be used as a reliable dating tool. In the U-poor calcite samples, measured 206Pb/207Pb ratios have a wide range, do not correlate with Ba concentration as would be expected if excess Ra was present, and reach a value of about 1400, the highest ever reported for natural Pb. Calcite intergrown with opal contains excesses of both 206Pb and 207Pb derived from Rn diffusion and from direct ??-recoil from U-rich opal. Calcite from coatings devoid of opal

  6. A three dimensional scaffold with precise micro-architecture and surface micro-textures

    PubMed Central

    Mata, Alvaro; Kim, Eun Jung; Boehm, Cynthia A.; Fleischman, Aaron J.; Muschler, George F.; Roy, Shuvo

    2013-01-01

    A three-dimensional (3D) structure comprising precisely defined microarchitecture and surface micro-textures, designed to present specific physical cues to cells and tissues, may provide an efficient scaffold in a variety of tissue engineering and regenerative medicine applications. We report a fabrication technique based on microfabrication and soft lithography that permits for the development of 3D scaffolds with both precisely engineered architecture and tailored surface topography. The scaffold fabrication technique consists of three key steps starting with microfabrication of a mold using an epoxy-based photoresist (SU-8), followed by dual-sided molding of a single layer of polydimethylsiloxane (PDMS) using a mechanical jig for precise motion control; and finally, alignment, stacking, and adhesion of multiple PDMS layers to achieve a 3D structure. This technique was used to produce 3D Texture and 3D Smooth PDMS scaffolds, where the surface topography comprised 10 μm-diameter/height posts and smooth surfaces, respectively. The potential utility of the 3D microfabricated scaffolds, and the role of surface topography, were subsequently investigated in vitro with a combined heterogeneous population of adult human stem cells and their resultant progenitor cells, collectively termed connective tissue progenitors (CTPs), under conditions promoting the osteoblastic phenotype. Examination of bone-marrow derived CTPs cultured on the 3D Texture scaffold for 9 days revealed cell growth in three dimensions and increased cell numbers compared to those on the 3D Smooth scaffold. Furthermore, expression of alkaline phosphatase mRNA was higher on the 3D Texture scaffold, while osteocalcin mRNA expression was comparable for both types of scaffolds. PMID:19524292

  7. Cryptic microtextures and geological histories of K-rich alkali feldspars revealed by charge contrast imaging

    NASA Astrophysics Data System (ADS)

    Flude, Stephanie; Lee, Martin R.; Sherlock, Sarah C.; Kelley, Simon P.

    2012-06-01

    Charge contrast imaging in the scanning electron microscope can provide new insights into the scale and composition of alkali feldspar microtextures, and such information helps considerably with the interpretation of their geological histories and results of argon isotope thermochronological analyses. The effectiveness of this technique has been illustrated using potassium-rich alkali feldspars from the Dartmoor granite (UK). These feldspars contain strain-controlled lamellar crypto- and microperthites that are cross-cut by strain-free deuteric microperthites. The constituent albite- and orthoclase-rich phases of both microperthite generations can be readily distinguished by atomic number contrast imaging. The charge contrast results additionally show that sub-micrometre-sized albite `platelets' are commonplace between coarser exsolution lamellae and occur together to make cryptoperthites. Furthermore, charge contrast imaging reveals that the orthoclase-rich feldspar is an intergrowth of two phases, one that is featureless with uniform contrast and another that occurs as cross-cutting veins and grains with the {110} adularia habit. Transmission electron microscopy shows that the featureless feldspar is tweed orthoclase, whereas the veins and euhedral grains are composed of irregular microcline that has formed from orthoclase by `unzipping' during deuteric or hydrothermal alteration. The charge contrast imaging results are especially important in demonstrating that deuteric perthites are far more abundant in alkali feldspars than would be concluded from investigations using conventional microscopy techniques. The unexpected presence of such a high volume of replacement products has significant implications for understanding the origins and geological histories of crustal rocks and the use of alkali feldspars in geo- and thermochronology. Whilst the precise properties of feldspars that generate contrast remain unclear, the similarity between charge contrast images

  8. EBSD Study on Grain Boundary and Microtexture Evolutions During Friction Stir Processing of A413 Cast Aluminum Alloy

    NASA Astrophysics Data System (ADS)

    Shamanian, Morteza; Mostaan, Hossein; Safari, Mehdi; Szpunar, Jerzy A.

    2016-07-01

    The as-cast Al alloys contain heterogeneous distributions of non-deforming particles due to non-equilibrium solidification effects. Therefore, these alloys have poor tribological and mechanical behaviors. It is well known that using friction stir processing (FSP), very fine microstructure is created in the as-cast Al alloys, while their wear resistance can be improved. In this research work, FSP is used to locally refine a surface layer of the coarse as-cast microstructure of cast A413 Al alloy. The main objective of this study is to investigate the effect of FSP on microstructure and microtexture evolutions in A413 cast Al alloy. The grain boundary character distribution, grain structure, and microtexture evolutions in as-cast and friction stir processed A413 Al alloy are analyzed by electron back scatter diffraction technique. It is found that with the FSP, the fraction of low ∑boundary such as ∑3, 7, and 9 are increased. The obtained results show that there are no deformation texture components in the structure of friction stir processed samples. However, some of the main recrystallization texture components such as BR and cubeND are formed during FSP which indicate the occurrence of dynamic recrystallization phenomenon due to the severe plastic deformation induced by the rotation of tool.

  9. High cesium concentrations in groundwater in the upper 1.2 km of fractured crystalline rock - Influence of groundwater origin and secondary minerals

    NASA Astrophysics Data System (ADS)

    Mathurin, Frédéric A.; Drake, Henrik; Tullborg, Eva-Lena; Berger, Tobias; Peltola, Pasi; Kalinowski, Birgitta E.; Åström, Mats E.

    2014-05-01

    Dissolved and solid phase cesium (Cs) was studied in the upper 1.2 km of a coastal granitoid fracture network on the Baltic Shield (Äspö Hard Rock Laboratory and Laxemar area, SE Sweden). There unusually high Cs concentrations (up to 5-6 μg L-1) occur in the low-temperature (<20 °C) groundwater. The material includes water collected in earlier hydrochemical monitoring programs and secondary precipitates (fracture coatings) collected on the fracture walls, as follows: (a) hydraulically pristine fracture groundwater sampled through 23 surface boreholes equipped for the retrieval of representative groundwater at controlled depths (Laxemar area), (b) fracture groundwater affected by artificial drainage collected through 80 boreholes drilled mostly along the Äspö Hard Rock Laboratory (underground research facility), (c) surface water collected in local streams, a lake and sea bay, and shallow groundwater collected in 8 regolith boreholes, and (d) 84 new specimens of fracture coatings sampled in cores from the Äspö HRL and Laxemar areas. The groundwater in each area is different, which affects Cs concentrations. The highest Cs concentrations occurred in deep-seated saline groundwater (median Äspö HRL: 4.1 μg L-1; median Laxemar: 3.7 μg L-1) and groundwater with marine origin (Äspö HRL: 4.2 μg L-1). Overall lower, but variable, Cs concentrations were found in other types of groundwater. The similar concentrations of Cs in the saline groundwater, which had a residence time in the order of millions of years, and in the marine groundwater, which had residence times in the order of years, shows that duration of water-rock interactions is not the single and primary control of dissolved Cs in these systems. The high Cs concentrations in the saline groundwater is ascribed to long-term weathering of minerals, primarily Cs-enriched fracture coatings dominated by illite and mixed-layer clays and possibly wall rock micaceous minerals. The high Cs concentrations in the

  10. The role of extremophile in the redox reaction of Fe and As relating with the formation of secondary phase mineral in extreme environment, Norris Geyser Basin, Yellowstone National Park, USA

    NASA Astrophysics Data System (ADS)

    Koo, T. H.; Kim, J. Y.; Park, K. R.; Jung, D. H.; Geesey, G. G.; Kim, J. W.

    2015-12-01

    Redox reaction associated with microbial elemental respiration is a ubiquitous process in sediments and suspended particles at various temperatures or pH/Eh conditions. Particularly, changes in elemental redox states (structural or dissolved elemental form) induced by microbial respiration result in the unexpected biogeochemical reactions in the light of biotic/abiotic mineralization. The objective of the present study is, therefore to investigate the secondary phase mineralization through a-/biogeochemical Fe and As redox cycling in the acido-hyperhtermal Norris Geyser Basin (NGB) in Yellowstone National Park, USA, typical of the extreme condition. X-ray diffraction, scanning electron microscope with energy dispersive x-ray spectroscopy, X-ray absorption near edge structure, inductively coupled plasma-atomic emission spectrometer and liquid chromatography with ICP-mass spectroscopy with filtrated supernatant were performed for the mineralogical and hydro-geochemical analysis. The clay slurry collected from the active hot-spring of the NGB area (pH=3.5 and Temperature=78 ℃) was incubated with ("enrichment") or without the growth medium ("natural"). The control was prepared in the same condition except adding the glutaraldehyde to eliminate the microbial activity. The secondary phase mineral formation of the oxidative phase of Fe and As, and K identified as 'Pharmacosiderite' only appeared in the enrichment set suggesting a role of extremophiles in the mineral formation. The considerable population of Fe-oxidizer (Metallosphera yellowstonensis MK-1) and As-oxidizer (Sulfurihydrogenibium sp.) was measured by phylogenetic analysis in the present study area. The inhibition of As-oxidation in the low pH conditions was reported in the previous study, however the As-redox reaction was observed and consequently, precipitated the Pharmacosiderite only in the enrichment set suggesting a biotic mineralization. The present study collectively suggests that the microbial

  11. Kinetics and microtextures formation during serpentinization: role of grain scale processes and transport

    NASA Astrophysics Data System (ADS)

    malvoisin, B.; Brunet, F.; Carlut, J. H.

    2013-12-01

    Serpentinization of mantle rocks plays a key role on the physical properties of the lithosphere at mid-ocean ridges and in subduction zones. This reaction is controlled by processes occurring at scales ranging from the grain to the lithosphere but the relative importance of these processes on the kinetics and microtextures formation has not been investigated. First, hydrothermal experiments on powders of San Carlos olivine at 500 bars in the 250 - 350 °C range were monitored with a magnetic method to study the kinetics and processes of the reaction at the grain scale. For an initial grain size (IGS) > 5 μm, lizardite, brucite, magnetite and hydrogen formed at a rate one to two orders of magnitude slower than the kinetics used to model serpentinization-related processes. Moreover, the serpentinization rate decreased linearly with the square of the IGS and reaction progress vs. time curves displayed a sigmoid form. The kinetics were controlled by the dissolution of olivine increasing with its reactive surface area which was generated with two cooperating processes (etch pits and grain fracturing) during the first stages of the reaction. Then, hydrothermal experiments were conducted on sintered San Carlos olivine to investigate the role of transport on the reaction. On sintered with a grain size of 1 to 5 μm, low reaction progresses of ~ 3 % in 10 months were obtained and the rate of serpentinization was one order of magnitude slower than on powders and one order of magnitude faster than on a single grain of the size of the sintered. Kinetics were controlled by a coupling between the reaction rate at the grain scale and the rate of fluid pathways formation at grain boundaries. Lizardite precipitated where olivine dissolved whereas magnetite and brucite segregated at the surface of the sintered. These results are in agreement with the observation of magnetite formation and segregation in fractures in naturally serpentinized peridotites and could explain the sparse

  12. Time-temperature evolution of microtextures and contained fluids in a plutonic alkali feldspar during heating

    NASA Astrophysics Data System (ADS)

    Parsons, Ian; Fitz Gerald, John D.; Lee, James K. W.; Ivanic, Tim; Golla-Schindler, Ute

    2010-08-01

    Microtextural changes brought about by heating alkali feldspar crystals from the Shap granite, northern England, at atmospheric pressure, have been studied using transmission and scanning electron microscopy. A typical unheated phenocryst from Shap is composed of about 70 vol% of tweed orthoclase with strain-controlled coherent or semicoherent micro- and crypto-perthitic albite lamellae, with maximum lamellar thicknesses <1 μm. Semicoherent lamellae are encircled by nanotunnel loops in two orientations and cut by pull-apart cracks. The average bulk composition of this microtexture is Ab27.6Or71.8An0.6. The remaining 30 vol% is deuterically coarsened, microporous patch and vein perthite composed of incoherent subgrains of oligoclase, albite and irregular microcline. The largest subgrains are ~3 μm in diameter. Heating times in the laboratory were 12 to 6,792 h and T from 300°C into the melting interval at 1,100°C. Most samples were annealed at constant T but two were heated to simulate an 40Ar/39Ar step-heating schedule. Homogenisation of strain-controlled lamellae by Na↔K inter-diffusion was rapid, so that in all run products at >700°C, and after >48 h at 700°C, all such regions were essentially compositionally homogeneous, as indicated by X-ray analyses at fine scale in the transmission electron microscope. Changes in lamellar thickness with time at different T point to an activation energy of ~350 kJmol-1. A lamella which homogenised after 6,800 h at 600°C, therefore, would have required only 0.6 s to do so in the melting interval at 1,100°C. Subgrains in patch perthite homogenised more slowly than coherent lamellae and chemical gradients in patches persisted for >5,000 h at 700°C. Homogenisation T is in agreement with experimentally determined solvi for coherent ordered intergrowths, when a 50-100°C increase in T for An1 is applied. Homogenisation of lamellae appears to proceed in an unexpected manner: two smooth interfaces, microstructurally sharp

  13. Enumeration of Thiobacilli within pH-Neutral and Acidic Mine Tailings and Their Role in the Development of Secondary Mineral Soil

    PubMed Central

    Southam, G.; Beveridge, T. J.

    1992-01-01

    The Lemoine tailings of Chibougamau, Quebec, Canada, were deposited as a pH-neutral mineral conglomerate consisting of aluminum-silicates, iron-aluminum-silicates, pyrite, chalcopyrite, and sphalerite. These tailings are colonized by an active population of Thiobacillus ferrooxidans which is localized to an acid zone occupying 40% of the tailings' surface. This population peaked at 7 × 108 most probable number per gram of tailings during July and August 1990 and extended to a depth of 40 cm from the surface. Examination of samples over this depth profile by transmission electron microscopy and electron dispersive spectroscopy revealed a microbially mediated mineral transition from sulfides (below 40 cm) to chlorides and phosphates (at the surface). Silicate minerals were unaltered by microbial action. Transmission electron microscopy showed a tight association between Thiobacillus species and the sulfide minerals, which helps account for their prominence in tailings environments. Accurate enumeration of T. ferrooxidans from tailings required the disruption of their bonding to the mineral interface. Vortexing of a 10% aqueous suspension of the tailings material prior to most-probable-number analysis best facilitated this release. Even though heavy metals were highly mobile under acidic conditions at the Lemoine tailings, it was evident by transmission electron microscopy and electron dispersive spectroscopy that they were being immobilized as bona fide fine-grain minerals containing iron, copper, chlorine, phosphorus, and oxygen on bacterial surfaces and exopolymers. This biomineralization increased with increasing bacterial numbers and was most evident in the upper 3 cm of the acidic zone. Images PMID:16348721

  14. The distribution of secondary mineral phases along an eroding hillslope and its effect on carbon stabilization mechanisms and the fate of soil carbon fractions

    NASA Astrophysics Data System (ADS)

    Doetterl, Sebastian; Cornelis, Jean-Thomas; Opfergelt, Sophie; Boeckx, Pascal; Bodé, Samuel; Six, Johan; Van Oost, Kristof

    2014-05-01

    Soil redistribution processes can change soil carbon (C) dynamics drastically by moving carbon from high decomposition and re-sequestration environments at the eroding hillslope to low decomposition and burial at the depositional footslope and valley basin. This leads to not only spatially diverse soil carbon storage throughout the landscape, but also to qualitative changes of the transported carbon and the mineral phase. The interaction between those parameters and the effect on stabilization mechanisms for soil C are still a matter of debate. Here, we present an analysis that aims to clarify the bio/geo-chemical and mineralogical components involved in stabilizing C at various depths along an eroding cropped slope and how this affects the abundance of microbial derived carbon. We use the results of an incubation experiment combined with the abundance of amino sugars in different isolated soil C fractions as a tracer for the stability of the respective fraction. We applied further (i) a sequential extraction of the reactive soil phase using pyrophosphate, oxalate and dithionite-citrate-bicarbonate, and (ii) a qualitative analysis of the clay mineralogy, to analyze the changes in the mineral phase for the different isolated fractions along the slope transect. Our results emphasize the importance of physical protection within microaggregates to stabilize buried, chemically labile C. Our data further indicates that the stability of these aggregates is related to the presence of organo-mineral associations and poorly crystalline minerals. However, decreasing contents of these minerals with depth indicate a temporal limitation of this stabilization mechanism. Non-expandable clay minerals experience a relative enrichment at the depositional site while expandable clay minerals experience the same at the eroding site. These changes in clay mineralogy along the slope are partly responsible for the abundance of silt and clay associated C and the effectiveness of the clay

  15. Mathematical model for bone mineralization

    PubMed Central

    Komarova, Svetlana V.; Safranek, Lee; Gopalakrishnan, Jay; Ou, Miao-jung Yvonne; McKee, Marc D.; Murshed, Monzur; Rauch, Frank; Zuhr, Erica

    2015-01-01

    Defective bone mineralization has serious clinical manifestations, including deformities and fractures, but the regulation of this extracellular process is not fully understood. We have developed a mathematical model consisting of ordinary differential equations that describe collagen maturation, production and degradation of inhibitors, and mineral nucleation and growth. We examined the roles of individual processes in generating normal and abnormal mineralization patterns characterized using two outcome measures: mineralization lag time and degree of mineralization. Model parameters describing the formation of hydroxyapatite mineral on the nucleating centers most potently affected the degree of mineralization, while the parameters describing inhibitor homeostasis most effectively changed the mineralization lag time. Of interest, a parameter describing the rate of matrix maturation emerged as being capable of counter-intuitively increasing both the mineralization lag time and the degree of mineralization. We validated the accuracy of model predictions using known diseases of bone mineralization such as osteogenesis imperfecta and X-linked hypophosphatemia. The model successfully describes the highly nonlinear mineralization dynamics, which includes an initial lag phase when osteoid is present but no mineralization is evident, then fast primary mineralization, followed by secondary mineralization characterized by a continuous slow increase in bone mineral content. The developed model can potentially predict the function for a mutated protein based on the histology of pathologic bone samples from mineralization disorders of unknown etiology. PMID:26347868

  16. Characterization of the sulphate mineral coquimbite, a secondary iron sulphate from Javier Ortega mine, Lucanas Province, Peru - Using infrared, Raman spectroscopy and thermogravimetry

    NASA Astrophysics Data System (ADS)

    Frost, Ray L.; Gobac, Željka Žigovečki; López, Andrés; Xi, Yunfei; Scholz, Ricardo; Lana, Cristiano; Lima, Rosa Malena Fernandes

    2014-04-01

    The mineral coquimbite has been analysed using a range of techniques including SEM with EDX, thermal analytical techniques and Raman and infrared spectroscopy. The mineral originated from the Javier Ortega mine, Lucanas Province, Peru. The chemical formula was determined as ()∑2.00()3·9HO. Thermal analysis showed a total mass loss of ˜73.4% on heating to 1000 °C. A mass loss of 30.43% at 641.4 °C is attributed to the loss of SO3. Observed Raman and infrared bands were assigned to the stretching and bending vibrations of sulphate tetrahedra, aluminium oxide/hydroxide octahedra, water molecules and hydroxyl ions. The Raman spectrum shows well resolved bands at 2994, 3176, 3327, 3422 and 3580 cm-1 attributed to water stretching vibrations. Vibrational spectroscopy combined with thermal analysis provides insight into the structure of coquimbite.

  17. Secondary osteoporosis.

    PubMed

    Sheu, Angela; Diamond, Terry

    2016-06-01

    Secondary osteoporosis is less common than primary osteoporosis. It may be suspected in patients who present with a fragility fracture despite having no risk factors for osteoporosis. In addition, secondary osteoporosis should be considered if the bone density Z-score is -2.5 or less. Consider the fracture site and presence of other clinical clues to guide investigations for an underlying cause. The tests to use are those that are indicated for the suspected cause. Baseline investigations include tests for bone and mineral metabolism (calcium, phosphate, alkaline phosphatase, 25-hydroxyvitamin D, parathyroid hormone), liver and kidney function, full blood count and thyroid-stimulating hormone. More detailed testing may be required in patients with severe osteoporosis.

  18. Secondary osteoporosis

    PubMed Central

    Sheu, Angela; Diamond, Terry

    2016-01-01

    SUMMARY Secondary osteoporosis is less common than primary osteoporosis. It may be suspected in patients who present with a fragility fracture despite having no risk factors for osteoporosis. In addition, secondary osteoporosis should be considered if the bone density Z-score is –2.5 or less. Consider the fracture site and presence of other clinical clues to guide investigations for an underlying cause. The tests to use are those that are indicated for the suspected cause. Baseline investigations include tests for bone and mineral metabolism (calcium, phosphate, alkaline phosphatase, 25-hydroxyvitamin D, parathyroid hormone), liver and kidney function, full blood count and thyroid-stimulating hormone. More detailed testing may be required in patients with severe osteoporosis. PMID:27346916

  19. Secondary osteoporosis.

    PubMed

    Sheu, Angela; Diamond, Terry

    2016-06-01

    Secondary osteoporosis is less common than primary osteoporosis. It may be suspected in patients who present with a fragility fracture despite having no risk factors for osteoporosis. In addition, secondary osteoporosis should be considered if the bone density Z-score is -2.5 or less. Consider the fracture site and presence of other clinical clues to guide investigations for an underlying cause. The tests to use are those that are indicated for the suspected cause. Baseline investigations include tests for bone and mineral metabolism (calcium, phosphate, alkaline phosphatase, 25-hydroxyvitamin D, parathyroid hormone), liver and kidney function, full blood count and thyroid-stimulating hormone. More detailed testing may be required in patients with severe osteoporosis. PMID:27346916

  20. Estimation of martensite feature size in a low-carbon alloy steel by microtexture analysis of boundaries.

    PubMed

    Karthikeyan, T; Dash, Manmath Kumar; Saroja, S; Vijayalakshmi, M

    2015-01-01

    A methodology for classifying the hierarchy of martensite boundaries from the EBSD microtexture data of low-carbon steel is presented. Quaternion algebra has been used to calculate the ideal misorientation between product α variants for Kurdjumov-Sachs (KS) and its nearby orientation relationships, and arrive at the misorientation angle-axis set corresponding to packet (12 types), block (3 types) and sub-block boundaries. Analysis of proximity of experimental misorientation between data points from the theoretical misorientation set is found to be useful for identifying the different types of martensite boundaries. The optimal OR in the alloy system and the critical deviation threshold for identification of martensite boundaries could both be ascertained by invoking the 'Enhancement Factor' concept. The prior-γ grain boundaries, packet, block and sub-block boundaries could be identified reasonably well, and their average intercept lengths in a typical tempered martensite microstructure of 9Cr-1Mo-0.1C steel was estimated as 31 μm, 14 μm, 9 μm and 4 μm respectively.

  1. Estimation of martensite feature size in a low-carbon alloy steel by microtexture analysis of boundaries.

    PubMed

    Karthikeyan, T; Dash, Manmath Kumar; Saroja, S; Vijayalakshmi, M

    2015-01-01

    A methodology for classifying the hierarchy of martensite boundaries from the EBSD microtexture data of low-carbon steel is presented. Quaternion algebra has been used to calculate the ideal misorientation between product α variants for Kurdjumov-Sachs (KS) and its nearby orientation relationships, and arrive at the misorientation angle-axis set corresponding to packet (12 types), block (3 types) and sub-block boundaries. Analysis of proximity of experimental misorientation between data points from the theoretical misorientation set is found to be useful for identifying the different types of martensite boundaries. The optimal OR in the alloy system and the critical deviation threshold for identification of martensite boundaries could both be ascertained by invoking the 'Enhancement Factor' concept. The prior-γ grain boundaries, packet, block and sub-block boundaries could be identified reasonably well, and their average intercept lengths in a typical tempered martensite microstructure of 9Cr-1Mo-0.1C steel was estimated as 31 μm, 14 μm, 9 μm and 4 μm respectively. PMID:25464145

  2. Relationship Between Changes in Serum Urate and Bone Mineral Density During Treatment with Thiazide Diuretics: Secondary Analysis from a Randomized Controlled Trial.

    PubMed

    Dalbeth, Nicola; Gamble, Gregory D; Horne, Anne; Reid, Ian R

    2016-05-01

    In observational studies, serum urate concentrations associate with bone mineral density (BMD) and reduced risk of fractures. Thiazide diuretics slow the bone loss in healthy older adults, are associated with reduced incidence of fracture and also increase serum urate. We hypothesized that changes in serum urate are associated with changes in BMD during treatment with thiazide diuretics. We analysed data from a double-blind randomized controlled trial of hydrochlorothiazide (50 mg per day) and placebo in normal post-menopausal women. The relationship between change in serum urate and change in BMD after 2 years of treatment was examined using Spearman correlation and multiple linear regression models. Total body BMD increased in the hydrochlorothiazide group by 0.52 % and reduced in the placebo group by 0.29 % over 2 years (between group difference P = 0.0034). Serum urate increased in the hydrochlorothiazide group by 0.038 mmol/L and reduced in the placebo group by 0.004 mmol/L (between group difference P < 0.0001). At Year 2, there was a positive relationship between the change in serum urate and change in total body BMD for entire study population (r = 0.32, P = 0.0002) and for the hydrochlorothiazide group (r = 0.29, P = 0.023). The association between change in serum urate and change in total body BMD persisted after adjusting for treatment allocation, and change in weight, serum calcium, urinary calcium and serum creatinine (P change in serum urate = 0.043). These data raise the possibility that the effects of hydrochlorothiazide on BMD may be mediated, in part, by changes in serum urate concentrations.

  3. Relating rheological measurements to primary and secondary skin feeling when mineral-based and Fischer-Tropsch wax-based cosmetic emulsions and jellies are applied to the skin.

    PubMed

    Bekker, M; Webber, G V; Louw, N R

    2013-08-01

    Rheology measurements were correlated to skin sensations occurring when cream and petroleum jelly cosmetic products containing different amounts of synthetic Fischer-Tropsch wax were applied to the skin. A panel of 15 people with a background in cosmetic product development were asked to rate skin feelings when a range of petroleum jelly and cream samples are applied to the skin. Primary skin feel, or the spreadability of a cosmetic product, was correlated to the product's flow onset and maximum viscosity as measured by a Anton Paar rheometer, whereas secondary skin feel or the sensation occurring at the end of application when the product was completely rubbed into the skin was correlated to the product's viscosity measured at high shear rates. The cream samples prepared with a petroleum jelly containing 10% and 20% Fischer-Tropsch wax fell within the boundary of good primary skin feeling of cream products. Predominantly, synthetic petroleum jellies were given the best assessments in terms of primary skin feeling and were used with mineral-based petroleum jellies to determine the boundary of good primary skin feeling for petroleum jelly products. The further away a product falls from this rheological boundary the poorer the skin feeling assessment appears to be by the panel. Products containing Fischer-Tropsch waxes were given the best assessment by the panel for secondary skin feeling. Comments from the panel include that these products feel silky and light on the skin. The higher the Fischer-Tropsch wax content, the lower viscosity was at high shear rate (ϒ = 500 s(-1) ) and the higher the assessment by the panel. Rheological measurements can be used to objectively determine skin sensation when products are applied to the skin; this may shorten research and development times. A rheology boundary of certain product viscosity and shear stress applied is associated with good primary skin feeling for lotions, creams and petroleum jellies. Lower product viscosity

  4. Relating rheological measurements to primary and secondary skin feeling when mineral-based and Fischer-Tropsch wax-based cosmetic emulsions and jellies are applied to the skin.

    PubMed

    Bekker, M; Webber, G V; Louw, N R

    2013-08-01

    Rheology measurements were correlated to skin sensations occurring when cream and petroleum jelly cosmetic products containing different amounts of synthetic Fischer-Tropsch wax were applied to the skin. A panel of 15 people with a background in cosmetic product development were asked to rate skin feelings when a range of petroleum jelly and cream samples are applied to the skin. Primary skin feel, or the spreadability of a cosmetic product, was correlated to the product's flow onset and maximum viscosity as measured by a Anton Paar rheometer, whereas secondary skin feel or the sensation occurring at the end of application when the product was completely rubbed into the skin was correlated to the product's viscosity measured at high shear rates. The cream samples prepared with a petroleum jelly containing 10% and 20% Fischer-Tropsch wax fell within the boundary of good primary skin feeling of cream products. Predominantly, synthetic petroleum jellies were given the best assessments in terms of primary skin feeling and were used with mineral-based petroleum jellies to determine the boundary of good primary skin feeling for petroleum jelly products. The further away a product falls from this rheological boundary the poorer the skin feeling assessment appears to be by the panel. Products containing Fischer-Tropsch waxes were given the best assessment by the panel for secondary skin feeling. Comments from the panel include that these products feel silky and light on the skin. The higher the Fischer-Tropsch wax content, the lower viscosity was at high shear rate (ϒ = 500 s(-1) ) and the higher the assessment by the panel. Rheological measurements can be used to objectively determine skin sensation when products are applied to the skin; this may shorten research and development times. A rheology boundary of certain product viscosity and shear stress applied is associated with good primary skin feeling for lotions, creams and petroleum jellies. Lower product viscosity

  5. Mineral Chart

    MedlinePlus

    ... How Can I Help a Friend Who Cuts? Mineral Chart KidsHealth > For Teens > Mineral Chart Print A A A Text Size en ... sources of calcium. You'll also find this mineral in broccoli and dark green, leafy vegetables. Soy ...

  6. Pyrophanite pseudomorphs after perovskite in Perkupa serpentinites (Hungary): a microtextural study and geological implications

    NASA Astrophysics Data System (ADS)

    Zajzon, N.; Váczi, T.; Fehér, B.; Takács, Á.; Szakáll, S.; Weiszburg, T. G.

    2013-09-01

    Pyrophanite in serpentinite at Perkupa (Hungary) is described in detail for the first time as a replacement product of perovskite. It occurs as a 20- to 30-μm-wide rim, mantling a remnant core composed of perovskite or its alteration products. The pyrophanite rim consists of an inner zone, representing a pseudomorph after perovskite, and an outer overgrowth zone. Raman mapping and electron backscatter diffraction data show that the pyrophanite rims typically represent single crystals rather than being composed of multiple domains in different crystallographic orientations. Perovskite occurs exclusively in the core of pyrophanite and was identified as the orthorhombic CaTiO3 phase, based on Raman spectra. Heterogeneous, polyphase mineral cores, consisting of calcite, anatase and/or brookite, kassite, and Mn-bearing kassite, in some cases in association with relict perovskite, are typical in the larger pyrophanite-rimmed grains. The crystallographically coherent pyrophanite rims could have formed through a process where the precursor perovskite crystal acted as a structural template for the newly forming phase, that is, by interface-coupled dissolution reprecipitation during serpentinization of the precursor rock. This alteration of perovskite to pyrophanite was not complete, resulting in the presence of perovskite fragments enclosed in pyrophanite. During the metamorphic evolution of the rock, some of the remnant perovskite cores further altered to TiO2 polymorphs (anatase and brookite) and calcite, via transitional alteration products.

  7. Secondary effects of glyphosate on plants

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Glyphosate is a unique herbicide with interesting secondary effects. Unfortunately, some have assumed that the secondary effects that occur in glyphosate-susceptible plants treated with glyphosate, such as altered mineral nutrition, reduced phenolic compound production and pathogen resistance, also ...

  8. Reply to 'Commentary: Assessment of past infiltration fluxes through Yucca Mountain on the basis of the secondary mineral record-is it a viable methodology?', by Y.V. Dublyansky and S.Z. Smirnov

    SciTech Connect

    Sonnenthal, Eric; Xu, Tianfu; Bodvarrson, Gudmundur

    2005-03-14

    Xu et al. (2003) presented results of a reaction-transport model for calcite deposition in the unsaturated zone at Yucca Mountain, and compared the model results to measured abundances in core from a surface-based borehole. Marshall et al. (2003) used the calcite distribution in the Topopah Spring Tuff to estimate past seepage into lithophysal cavities as an analog for seepage into the potential repository waste emplacement drifts at Yucca Mountain in southern Nevada (USA). Dublyansky and Smirnov (2005) wrote a commentary paper to Marshall et al. (2003) and Xu et al. (2003), containing two points: (1) questionable phenomenological model for the secondary mineral deposits and (2) inappropriate thermal boundary conditions. In this reply we address primarily the modeling approach by showing results of a sensitivity simulation regarding the effect of an elevated temperature history that approximates the temperature history inferred from fluid inclusions by Wilson et al. (2003). Modeled calcite abundances using the time-varying temperature history are similar to the results for the steady-state ambient temperature profile (Xu et al., 2003), and are still consistent with the measured abundances at the proposed repository horizon.

  9. Compositional and Microtextural Analysis of Basaltic Feedstock Materials Used for the 2010 ISRU Field Tests, Mauna Kea, Hawaii

    NASA Astrophysics Data System (ADS)

    Marin, N.; Farmer, J. D.; Zacny, K.; Sellar, R. G.; Nunez, J.

    2011-12-01

    This study seeks to understand variations in composition and texture of basaltic pyroclastic materials used in the 2010 International Lunar Surface Operation-In-Situ Resource Utilization Analogue Test (ILSO-ISRU) held on the slopes of Mauna Kea Volcano, Hawaii (1). The quantity and quality of resources delivered by ISRU depends upon the nature of the materials processed (2). We obtained a one-meter deep auger cuttings sample of a basaltic regolith at the primary site for feed stock materials being mined for the ISRU field test. The auger sample was subdivided into six, ~16 cm depth increments and each interval was sampled and characterized in the field using the Multispectral Microscopic Imager (MMI; 3) and a portable X-ray Diffractometer (Terra, InXitu Instruments, Inc.). Splits from each sampled interval were returned to the lab and analyzed using more definitive methods, including high resolution Powder X-ray Diffraction and Thermal Infrared (TIR) spectroscopy. The mineralogy and microtexture (grain size, sorting, roundness and sphericity) of the auger samples were determined using petrographic point count measurements obtained from grain-mount thin sections. NIH Image J (http://rsb.info.nih.gov/ij/) was applied to digital images of thin sections to document changes in particle size with depth. Results from TIR showed a general predominance of volcanic glass, along with plagioclase, olivine, and clinopyroxene. In addition, thin section and XRPD analyses showed a down core increase in the abundance of hydrated iron oxides (as in situ weathering products). Quantitative point count analyses confirmed the abundance of volcanic glass in samples, but also revealed olivine and pyroxene to be minor components, that decreased in abundance with depth. Furthermore, point count and XRD analyses showed a decrease in magnetite and ilmenite with depth, accompanied by an increase in Fe3+phases, including hematite and ferrihydrite. Image J particle analysis showed that the

  10. Industrial Minerals.

    ERIC Educational Resources Information Center

    Brady, Lawrence L.

    1983-01-01

    Discusses trends in and factors related to the production of industrial minerals during 1982, indicating that, as 1981 marked a downturn in production of industrial minerals, 1982 continued the trend with temporary and permanent cutbacks in mine and plant production. Includes highlights of several conferences/conference papers in this field.…

  11. Extraterrestrial magnetic minerals

    NASA Astrophysics Data System (ADS)

    Pechersky, D. M.; Markov, G. P.; Tsel'movich, V. A.; Sharonova, Z. V.

    2012-07-01

    Thermomagnetic and microprobe analyses are carried out and a set of magnetic characteristics are measured for 25 meteorites and 3 tektites from the collections of the Vernadsky Geological Museum of the Russian Academy of Sciences and Museum of Natural History of the North-East Interdisciplinary Science Research Institute, Far Eastern Branch of the Russian Academy of Sciences. It is found that, notwithstanding their type, all the meteorites contain the same magnetic minerals and only differ by concentrations of these minerals. Kamacite with less than 10% nickel is the main magnetic mineral in the studied samples. Pure iron, taenite, and schreibersite are less frequent; nickel, various iron spinels, Fe-Al alloys, etc., are very rare. These minerals are normally absent in the crusts of the Earth and other planets. The studied meteorites are more likely parts of the cores and lower mantles of the meteoritic parent bodies (the planets). Uniformity in the magnetic properties of the meteorites and the types of their thermomagnetic (MT) curves is violated by secondary alterations of the meteorites in the terrestrial environment. The sediments demonstrate the same monotony as the meteorites: kamacite is likely the only extraterrestrial magnetic mineral, which is abundant in sediments and associated with cosmic dust. The compositional similarity of kamacite in iron meteorites and in cosmic dust is due to their common source; the degree of fragmentation of the material of the parent body is the only difference.

  12. Identifying Minerals from Their Infra-red Spectra.

    ERIC Educational Resources Information Center

    Paterson, W. G.

    1986-01-01

    Describes a British secondary school's use of a spectrometer to identify minerals. Discusses the origins of mineral spectra, the preparation of the specimen, the actual spectroscopic scanning, and the interpretation of the spectra. (TW)

  13. Mineral Quantification.

    PubMed

    2016-01-01

    Optimal intakes of elements, such as sodium, potassium, magnesium, calcium, manganese, copper, zinc and iodine, can reduce individual risk factors including those related to cardiovascular diseases among humans and animals. In order to meet the need for vitamins, major minerals, trace minerals, fatty acids and amino acids, it is necessary to include a full spectrum programme that can deliver all of the nutrients in the right ratio. Minerals are required for normal growth, activities of muscles, skeletal development (such as calcium), cellular activity, oxygen transport (copper and iron), chemical reactions in the body, intestinal absorption (magnesium), fluid balance and nerve transmission (sodium and potassium), as well as the regulation of the acid base balance (phosphorus). The chapter discusses the chemical and instrumentation techniques used for estimation of minerals such as N, P, Ca, Mg, K, Na, Fe, Cu, Zn, B and Mb. PMID:26939263

  14. Mineral Quantification.

    PubMed

    2016-01-01

    Optimal intakes of elements, such as sodium, potassium, magnesium, calcium, manganese, copper, zinc and iodine, can reduce individual risk factors including those related to cardiovascular diseases among humans and animals. In order to meet the need for vitamins, major minerals, trace minerals, fatty acids and amino acids, it is necessary to include a full spectrum programme that can deliver all of the nutrients in the right ratio. Minerals are required for normal growth, activities of muscles, skeletal development (such as calcium), cellular activity, oxygen transport (copper and iron), chemical reactions in the body, intestinal absorption (magnesium), fluid balance and nerve transmission (sodium and potassium), as well as the regulation of the acid base balance (phosphorus). The chapter discusses the chemical and instrumentation techniques used for estimation of minerals such as N, P, Ca, Mg, K, Na, Fe, Cu, Zn, B and Mb.

  15. 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.

  16. The Chemistry of Rocks and Minerals

    ERIC Educational Resources Information Center

    Pezaro, Peter; And Others

    1978-01-01

    Describes the curriculum, operation and pilot study of a secondary school course on the study of rocks and minerals. Teacher training procedures and modification of the curriculum for other countries (outside of Israel) are discussed. (CP)

  17. 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)

  18. Secondary parkinsonism

    MedlinePlus

    Parkinsonism - secondary; Atypical Parkinson disease ... to be less responsive to medical therapy than Parkinson disease. ... Unlike Parkinson disease, some types of secondary parkinsonism may stabilize or even improve if the underlying cause is treated. Brain ...

  19. 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.

  20. Influence of cross-rolling on the micro-texture and biodegradation of pure iron as biodegradable material for medical implants.

    PubMed

    Obayi, Camillus Sunday; Tolouei, Ranna; Paternoster, Carlo; Turgeon, Stephane; Okorie, Boniface Adeleh; Obikwelu, Daniel Oray; Cassar, Glenn; Buhagiar, Joseph; Mantovani, Diego

    2015-04-01

    Iron-based biodegradable metals have been shown to present high potential in cardiac, vascular, orthopaedic and dental in adults, as well as paediatric, applications. These require suitable mechanical properties, adequate biocompatibility while guaranteeing a low toxicity of degradation products. For example, in cardiac applications, stents need to be made by homogeneous and isotropic materials in order to prevent sudden failures which would impair the deployment site. Besides, the presence of precipitates and pores, chemical inhomogeneity or other anisotropic microstructural defects may trigger stress concentration phenomena responsible for the early collapse of the device. Metal manufacturing processes play a fundamental role towards the final microstructure and mechanical properties of the materials. The present work assesses the effect of mode of rolling on the micro-texture evolution, mechanical properties and biodegradation behaviour of polycrystalline pure iron. Results indicated that cross-rolled samples recrystallized with lower rates than the straight-rolled ones due to a reduction in dislocation density content and an increase in intensity of {100} crystallographic plane which stores less energy of deformation responsible for primary recrystallization. The degradation resulted to be more uniform for cross-rolled samples, while the corrosion rates of cross-rolled and straight-rolled samples did not show relevant differences in simulated body solution. Finally, this work shows that an adequate compromise between biodegradation rate, strength and ductility could be achieved by modulating the deformation mode during cold rolling. PMID:25644452

  1. Vitamins and Minerals

    MedlinePlus

    ... I Help a Friend Who Cuts? Vitamins and Minerals KidsHealth > For Teens > Vitamins and Minerals Print A ... of a good thing? What Are Vitamins and Minerals? Vitamins and minerals make people's bodies work properly. ...

  2. [Secondary hypertension].

    PubMed

    Yoshida, Yuichi; Shibata, Hirotaka

    2015-11-01

    Hypertension is a common disease and a crucial predisposing factor of cardiovascular diseases. Approximately 10% of hypertensive patients are secondary hypertension, a pathogenetic factor of which can be identified. Secondary hypertension consists of endocrine, renal, and other diseases. Primary aldosteronism, Cushing's syndrome, pheochromocytoma, hyperthyroidism, and hypothyroidism result in endocrine hypertension. Renal parenchymal hypertension and renovascular hypertension result in renal hypertension. Other diseases such as obstructive sleep apnea syndrome are also very prevalent in secondary hypertension. It is very crucial to find and treat secondary hypertension at earlier stages since most secondary hypertension is curable or can be dramatically improved by specific treatment. One should keep in mind that screening of secondary hypertension should be done at least once in a daily clinical practice. PMID:26619670

  3. 30 CFR 56.3400 - Secondary breakage.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... 30 Mineral Resources 1 2011-07-01 2011-07-01 false Secondary breakage. 56.3400 Section 56.3400 Mineral Resources MINE SAFETY AND HEALTH ADMINISTRATION, DEPARTMENT OF LABOR METAL AND NONMETAL MINE SAFETY AND HEALTH SAFETY AND HEALTH STANDARDS-SURFACE METAL AND NONMETAL MINES Ground Control...

  4. 30 CFR 56.3400 - Secondary breakage.

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... 30 Mineral Resources 1 2013-07-01 2013-07-01 false Secondary breakage. 56.3400 Section 56.3400 Mineral Resources MINE SAFETY AND HEALTH ADMINISTRATION, DEPARTMENT OF LABOR METAL AND NONMETAL MINE SAFETY AND HEALTH SAFETY AND HEALTH STANDARDS-SURFACE METAL AND NONMETAL MINES Ground Control...

  5. 30 CFR 56.3400 - Secondary breakage.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... 30 Mineral Resources 1 2010-07-01 2010-07-01 false Secondary breakage. 56.3400 Section 56.3400 Mineral Resources MINE SAFETY AND HEALTH ADMINISTRATION, DEPARTMENT OF LABOR METAL AND NONMETAL MINE SAFETY AND HEALTH SAFETY AND HEALTH STANDARDS-SURFACE METAL AND NONMETAL MINES Ground Control...

  6. 30 CFR 56.3400 - Secondary breakage.

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... 30 Mineral Resources 1 2014-07-01 2014-07-01 false Secondary breakage. 56.3400 Section 56.3400 Mineral Resources MINE SAFETY AND HEALTH ADMINISTRATION, DEPARTMENT OF LABOR METAL AND NONMETAL MINE SAFETY AND HEALTH SAFETY AND HEALTH STANDARDS-SURFACE METAL AND NONMETAL MINES Ground Control...

  7. 30 CFR 56.3400 - Secondary breakage.

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... 30 Mineral Resources 1 2012-07-01 2012-07-01 false Secondary breakage. 56.3400 Section 56.3400 Mineral Resources MINE SAFETY AND HEALTH ADMINISTRATION, DEPARTMENT OF LABOR METAL AND NONMETAL MINE SAFETY AND HEALTH SAFETY AND HEALTH STANDARDS-SURFACE METAL AND NONMETAL MINES Ground Control...

  8. Defective skeletal mineralization in pediatric CKD.

    PubMed

    Wesseling-Perry, Katherine

    2015-04-01

    Although traditional diagnosis and treatment of renal osteodystrophy focused on changes in bone turnover, current data demonstrate that abnormalities in skeletal mineralization are also prevalent in pediatric chronic kidney disease (CKD) and likely contribute to skeletal morbidities that continue to plague this population. It is now clear that alterations in osteocyte biology, manifested by changes in osteocytic protein expression, occur in early CKD before abnormalities in traditional measures of mineral metabolism are apparent and may contribute to defective skeletal mineralization. Current treatment paradigms advocate the use of 1,25(OH)2vitamin D for the control of secondary hyperparathyroidism; however, these agents fail to correct defective skeletal mineralization and may exacerbate already altered osteocyte biology. Further studies are critically needed to identify the initial trigger for abnormalities of skeletal mineralization as well as the potential effects that current therapeutic options may have on osteocyte biology and bone mineralization. PMID:25638580

  9. Defective skeletal mineralization in pediatric CKD.

    PubMed

    Wesseling-Perry, Katherine

    2015-04-01

    Although traditional diagnosis and treatment of renal osteodystrophy focused on changes in bone turnover, current data demonstrate that abnormalities in skeletal mineralization are also prevalent in pediatric chronic kidney disease (CKD) and likely contribute to skeletal morbidities that continue to plague this population. It is now clear that alterations in osteocyte biology, manifested by changes in osteocytic protein expression, occur in early CKD before abnormalities in traditional measures of mineral metabolism are apparent and may contribute to defective skeletal mineralization. Current treatment paradigms advocate the use of 1,25(OH)2vitamin D for the control of secondary hyperparathyroidism; however, these agents fail to correct defective skeletal mineralization and may exacerbate already altered osteocyte biology. Further studies are critically needed to identify the initial trigger for abnormalities of skeletal mineralization as well as the potential effects that current therapeutic options may have on osteocyte biology and bone mineralization.

  10. An integrated microtextural and chemical approach to zircon geochronology: refining the Archaean history of the Napier Complex, east Antarctica

    NASA Astrophysics Data System (ADS)

    Kelly, Nigel M.; Harley, Simon L.

    2005-03-01

    Integrated textural and chemical characterisation of zircon is used to refine the U-Pb geochronology of the Archaean, ultra-high temperature Napier Complex, east Antarctica. Scanning electron microscope characterisation of zircon and the rare earth element compositions of zircon, garnet and orthopyroxene are integrated to place zircon growth in an assemblage context, thereby providing tighter constraints on the timing of magmatic and metamorphic events. Data indicate that magmatism occurred in the central and northern Napier Complex at ca. 2,990 Ma. A regional, relatively low-pressure metamorphic event occurred at ca. 2,850-2,840 Ma. Mineral REE data from garnet-bearing orthogneiss indicate that ca. 2,490-2,485 Ma U-Pb zircon ages provide an absolute minimum age for the ultrahigh temperature (UHT) foliation preserved in this rock. Internal zircon zoning relationships and estimated zircon-garnet DREE values from paragneiss suggest that an absolute minimum age of ultra-high temperature metamorphism is ca. 2,510 Ma, but that it is more likely to be older than ca. 2,545 Ma. We suggest that the high proportion of published zircon U-Pb data with ages between ca. 2,490-2,450 Ma reflects late, post-peak zircon growth and does not date the timing of peak UHT metamorphism.

  11. New Minerals and Science.

    ERIC Educational Resources Information Center

    Birch, William D.

    1997-01-01

    Defines geodiversity, compares it to biodiversity, and discusses the mineral classification system. Charts the discovery of new minerals in Australia over time and focuses on uses of these minerals in technological advances. (DDR)

  12. 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)

  13. 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 ...

  14. Chemical dissolution of sulfide minerals

    USGS Publications Warehouse

    Chao, T.T.; Sanzolone, R.F.

    1977-01-01

    Chemical dissolution treatments involving the use of aqua regia, 4 N HNO3, H2O2-ascorbic acid, oxalic acid, KClO3+HCl, and KClO3+HCl followed by 4 N HNO3 were applied to specimens of nine common sulfide minerals (galena, chalcopyrite, cinnabar, molybdenite, orpiment, pyrite, stibnite, sphalerite, and tetrahedrite) mixed individually with a clay loam soil. The resultant decrease in the total sulfur content of the mixture, as determined by using the Leco induction furnace, was used to evaluate the effectiveness of each chemical treatment. A combination of KClO3+HCl followed by 4 N HNO3 boiling gently for 20 min has been shown to be very effective in dissolving all the sulfide minerals. This treatment is recommended to dissolve metals residing in sulfide minerals admixed with secondary weathering products, as one step in a fractionation scheme whereby metals in soluble and adsorbed forms, and those associated with organic materials and secondary oxides, are first removed by other chemical extractants.

  15. [Secondary dyslipidemias].

    PubMed

    Vargová, V; Pytliak, M; Mechírová, V

    2012-03-01

    Dyslipidemias rank among the most important preventabile factors of atherogenesis and its progression. This topic is increasingly being discussed as e.g. more than 50% of Slovak population die on atherosclerotic complications. According to etiology we distinguish primary dyslipidemias with strictly genetic background and secondary ones with origin in other disease or pathological state. Secondary dyslipidemias accompany various diseases, from common (endocrinopathies, renal diseases etc) to rare ones (thesaurismosis etc.) and represents one of symptoms of these diseases. Apart from particular clinical follow up of diagnosed dysipidemias, basic screening and secondary causes as well as treatment due to updated guidelines is recuired. In this review we present the most frequent dyslipidemias of clinical practice.

  16. Determinants of pathologic mineralization.

    PubMed

    Kirsch, Thorsten

    2008-01-01

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

  17. Secondary Products

    Technology Transfer Automated Retrieval System (TEKTRAN)

    In spite of their name, "secondary" products are essential for plant survival. They are required for basic cell functions as well as communicating the plant's presence to the surrounding environment and defense against pests as defined in the broad sense (i.e., diseases, nematodes, insects and plan...

  18. Mineral Commodity Profiles: Selenium

    USGS Publications Warehouse

    Butterman, W.C.; Brown, R.D.

    2004-01-01

    Overview -- Selenium, which is one of the chalcogen elements in group 16 (or 6A) of the periodic table, is a semiconductor that is chemically similar to sulfur for which it substitutes in many minerals and synthetic compounds. It is a byproduct of copper refining and, to a much lesser extent, lead refining. It is used in many applications, the major ones being a decolorizer for glass, a metallurgical additive to free-machining varieties of ferrous and nonferrous alloys, a constituent in cadmium sulfoselenide pigments, a photoreceptor in xerographic copiers, and a semiconductor in electrical rectifiers and photocells. Refined selenium amounting to more than 1,800 metric tons (t) was produced by 14 countries in 2000. Japan, Canada, the United States, and Belgium, which were the four largest producers, accounted for nearly 85 percent of world production. An estimated 250 t of the world total is secondary selenium, which is recovered from scrapped xerographic copier drums and selenium rectifiers; the selenium in nearly all other uses is dissipated (not recoverable as waste or scrap). The present selenium reserve bases for the United States and the world (including the United States), which are associated with copper deposits, are expected to be able to satisfy demand for selenium for several decades without difficulty.

  19. Radioactive demonstration of final mineralized waste forms for Hanford waste treatment plant secondary waste (WTP-SW) by fluidized bed steam reforming (FBSR) using the bench scale reformer platform

    SciTech Connect

    Crawford, C.; Burket, P.; Cozzi, A.; Daniel, G.; Jantzen, C.; Missimer, D.

    2014-08-01

    The U.S. Department of Energy’s Office of River Protection (ORP) is responsible for the retrieval, treatment, immobilization, and disposal of Hanford’s tank waste. Currently there are approximately 56 million gallons of highly radioactive mixed wastes awaiting treatment. A key aspect of the River Protection Project (RPP) cleanup mission is to construct and operate the Waste Treatment and Immobilization Plant (WTP). The WTP will separate the tank waste into high-level and low-activity waste (LAW) fractions, both of which will subsequently be vitrified. The projected throughput capacity of the WTP LAW Vitrification Facility is insufficient to complete the RPP mission in the time frame required by the Hanford Federal Facility Agreement and Consent Order, also known as the Tri-Party Agreement (TPA), i.e. December 31, 2047. Therefore, Supplemental Treatment is required both to meet the TPA treatment requirements as well as to more cost effectively complete the tank waste treatment mission. In addition, the WTP LAW vitrification facility off-gas condensate known as WTP Secondary Waste (WTP-SW) will be generated and enriched in volatile components such as 137Cs, 129I, 99Tc, Cl, F, and SO4 that volatilize at the vitrification temperature of 1150°C in the absence of a continuous cold cap (that could minimize volatilization). The current waste disposal path for the WTP-SW is to process it through the Effluent Treatment Facility (ETF). Fluidized Bed Steam Reforming (FBSR) is being considered for immobilization of the ETF concentrate that would be generated by processing the WTP-SW. The focus of this current report is the WTP-SW.

  20. 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.

  1. 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)

  2. Mathematical Model for the Mineralization of Bone

    NASA Technical Reports Server (NTRS)

    Martin, Bruce

    1994-01-01

    A mathematical model is presented for the transport and precipitation of mineral in refilling osteons. One goal of this model was to explain calcification 'halos,' in which the bone near the haversian canal is more highly mineralized than the more peripheral lamellae, which have been mineralizing longer. It was assumed that the precipitation rate of mineral is proportional to the difference between the local concentration of calcium ions and an equilibrium concentration and that the transport of ions is by either diffusion or some other concentration gradient-dependent process. Transport of ions was assumed to be slowed by the accumulation of mineral in the matrix along the transport path. ne model also mimics bone apposition, slowing of apposition during refilling, and mineralization lag time. It was found that simple diffusion cannot account for the transport of calcium ions into mineralizing bone, because the diffusion coefficient is two orders of magnitude too low. If a more rapid concentration gradient-driven means of transport exists, the model demonstrates that osteonal geometry and variable rate of refilling work together to produce calcification halos, as well as the primary and secondary calcification effect reported in the literature.

  3. Mathematical Model for the Mineralization of Bone

    NASA Technical Reports Server (NTRS)

    Martin, Bruce

    1994-01-01

    A mathematical model is presented for the transport and precipitation of mineral in refilling osteons. One goal of this model was to explain calcification 'halos,' in which the bone near the haversian canal is more highly mineralized than the more peripheral lamellae, which have been mineralizing longer. It was assumed that the precipitation rate of mineral is proportional to the difference between the local concentration of calcium ions and an equilibrium concentration and that the transport of ions is by either diffusion or some other concentration gradient-dependent process. Transport of ions was assumed to be slowed by the accumulation of mineral in the matrix along the transport path. The model also mimics bone apposition, slowing of apposition during refilling, and mineralization lag time. It was found that simple diffusion cannot account for the transport of calcium ions into mineralizing bone, because the diffusion coefficient is two orders of magnitude too low. If a more rapid concentration gradient-driven means of transport exists, the model demonstrates that osteonal geometry and variable rate of refilling work together to produce calcification halos, as well as the primary and secondary calcification effect reported in the literature.

  4. Ion beam microtexturing of surfaces

    NASA Technical Reports Server (NTRS)

    Robinson, R. S.

    1981-01-01

    Some recent work in surface microtecturing by ion beam sputtering is described. The texturing is accomplished by deposition of an impurity onto a substrate while simultaneously bombarding it with an ion beam. A summary of the theory regarding surface diffusion of impurities and the initiation of cone formation is provided. A detailed experimental study of the time-development of individual sputter cones is described. A quasi-liquid coating was observed that apparently reduces the sputter rate of the body of a cone compared to the bulk material. Experimental measurements of surface diffusion activation energies are presented for a variety of substrate-seed combinations and range from about 0.3 eV to 1.2 eV. Observations of apparent crystal structure in sputter cones are discussed. Measurements of the critical temperature for cone formation are also given along with a correlation of critical temperature with substrate sputter rate.

  5. 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. PMID:15984571

  6. 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.

  7. Scientists observe fungi-dissolving minerals

    NASA Astrophysics Data System (ADS)

    Bhattacharya, Atreyee

    2012-10-01

    Ectomycorrhizal fungi (EMF) live in moist dark recesses and never see daylight. They cling to the roots of trees in boreal forests, break down soil minerals and supply essential elements and nutrients to the trees. Along the way, they play a distinct but not yet well-understood role in bioweathering, a process in which water, air, and organisms interact to break down soil minerals within the first few meters of Earth's surface. In a synthetically designed and controlled laboratory environment, Gazzè et al. cultured EMF; the researchers monitored the process as the fungi colonized a soil mineral on a petri dish over a period of 7 months. The authors then extracted individual grains of chlorite, a common soil-forming clay mineral, and cleaned the mineral surfaces to look at how the fungi had affected the mineral surfaces they came in contact with. Using atomic force microscopy, a specialized process that allows observations of three-dimensional features at nanometer (10-9 meter) scales, the authors found numerous primary channels, of the order of a micron (10-6 meters) in width and up to 50 nanometers in depth, from which smaller secondary channels extended outward. The network of channels resembled a herringbone-like pattern—evidence of dissolution by EMF.

  8. Heavy-mineral analysis and provenance of Yellow River sediments around the China Loess Plateau

    NASA Astrophysics Data System (ADS)

    Pan, Baotian; Pang, Hongli; Gao, Hongshan; Garzanti, Eduardo; Zou, Yu; Liu, Xiaopeng; Li, Fuqiang; Jia, Yunxia

    2016-09-01

    In its upper-middle reaches the Yellow River has high sand contents after traversing through large areas of desert and the China Loess Plateau. Understanding riverbed sediment composition in the channel is critical for the interpretation of the potential provenance, aeolian sand transport and the linkage between the Loess Plateau and the Yellow River. To address these issues, we collected 52 samples from the modern riverbed, proximal deserts, and major tributaries and used analyses of grain size, grain morphology, and heavy-mineral compositions, to establish the spatial distribution and characteristics of source regions and riverbed sediments. The heavy-mineral assemblages demonstrate significant variations for the different sections of the Yellow River. The riverbed samples from the upper reach are dominated by opaque minerals (limonite and magnetite), amphibole and epidote, with minor zircon, tourmaline and rutile. Riverbed sediments from the middle reach are garnet-rich, reflecting the widespread distribution of Mesozoic sandstones. This variability closely reflects the source regions. Our data show that seasonal tributaries (the "Ten Great Gullies") carrying detritus from the Ordos Plateau may account for the localized high garnet concentrations in the Inner Mongolia section of the upper reach. Scanning electron microscope (SEM) imaging of quartz grains show that the river sediments are characterized by composite microtextures acquired in both fluvial and eolian environments of the Hedong, Ulan Buh and Kubuq Deserts. The mineralogical composition in the upper reach (Lanzhou-Yinchuan) is similar to that of sediments in the Loess Plateau and Northeast Tibet Plateau (Western Lanzhou). However, the composition differs markedly from that in the Inner Mongolia section of the upper and middle reaches. This variation indicates that in the upper reach the Northeast Tibet Plateau contributes significant volumes of sediment to the Yellow River and Loess Plateau, but

  9. 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.

  10. SECONDARY OSTEOPOROSIS: PATHOPHYSIOLOGY AND MANAGEMENT

    PubMed Central

    Mirza, Faryal; Canalis, Ernesto

    2015-01-01

    Osteoporosis is a skeletal disorder characterized by decreased bone mineral density and compromised bone strength predisposing to an increased risk of fractures. Although idiopathic osteoporosis is the most common form of osteoporosis, secondary factors may contribute to the bone loss and increased fracture risk in patients presenting with fragility fractures or osteoporosis. Several medical conditions and medications significantly increase the risk for bone loss and skeletal fragility. This review focuses on some of the common causes of osteoporosis, addressing the underlying mechanisms, diagnostic approach and treatment of low bone mass in the presence of these conditions. PMID:25971649

  11. Uranium mineralization in southern Victoria Land, Antarctica

    SciTech Connect

    Dreschhoff, G.A.M.; Zeller, E.J.

    1986-01-01

    For the past 10 antarctic field seasons, an airborne gamma-ray spectrometric survey has been conducted over widely separated parts of the continent. Localized accumulations of both primary and secondary uranium minerals have been discovered at several localities scattered along the Transantarctic Mountains from the Scott Glacier to northern Victoria Land. A number of highly significant radiation anomalies have been discovered in the area between the Koettlitz Glacier and the Pyramid Trough. The occurrences consist of pegmatite vein complexes which contain an association of primary uranium and thorium minerals. Of still greater significance is the fact that abundant secondary uranium minerals were found in association with the primary deposits, and they indicate clearly that uranium is geochemically mobile under the conditions imposed by the arid polar climate that now exists in southern Victoria Land. Preliminary results of a uranium analysis performed by neutron activation indicate a concentration of 0.12% uranium in a composite sample from the two veins. Even higher levels of thorium are present. The nature of the primary uranium mineralization is currently under investigation. Preliminary results are discussed.

  12. 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...

  13. 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...

  14. 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...

  15. 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...

  16. 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...

  17. 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…

  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. 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.

  20. 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.

  1. 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.

  2. 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.

  3. 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.

  4. 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.

  5. 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.

  6. 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.

  7. 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.

  8. 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

  9. 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.

  10. The Miner's Canary

    ERIC Educational Resources Information Center

    Guinier, Lani

    2005-01-01

    Miners used canaries as early warning signals: when a canary gasped for breath, the miners knew there was a problem with the atmosphere in the mine. The experience of people of color in higher education can be used similarly as a diagnostic tool.

  11. 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…

  12. 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

  13. 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.

  14. Biological impact on mineral dissolution: Application of the lichen model to understanding mineral weathering in the rhizosphere

    PubMed Central

    Banfield, Jillian F.; Barker, William W.; Welch, Susan A.; Taunton, Anne

    1999-01-01

    Microorganisms modify rates and mechanisms of chemical and physical weathering and clay growth, thus playing fundamental roles in soil and sediment formation. Because processes in soils are inherently complex and difficult to study, we employ a model based on the lichen–mineral system to identify the fundamental interactions. Fixed carbon released by the photosynthetic symbiont stimulates growth of fungi and other microorganisms. These microorganisms directly or indirectly induce mineral disaggregation, hydration, dissolution, and secondary mineral formation. Model polysaccharides were used to investigate direct mediation of mineral surface reactions by extracellular polymers. Polysaccharides can suppress or enhance rates of chemical weathering by up to three orders of magnitude, depending on the pH, mineral surface structure and composition, and organic functional groups. Mg, Mn, Fe, Al, and Si are redistributed into clays that strongly adsorb ions. Microbes contribute to dissolution of insoluble secondary phosphates, possibly via release of organic acids. These reactions significantly impact soil fertility. Below fungi–mineral interfaces, mineral surfaces are exposed to dissolved metabolic byproducts. Through this indirect process, microorganisms can accelerate mineral dissolution, leading to enhanced porosity and permeability and colonization by microbial communities. PMID:10097050

  15. Mineral Commodity Summaries 2010

    USGS Publications Warehouse

    ,

    2010-01-01

    Each chapter of the 2010 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 2009 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. National reserves information for most mineral commodities found in this report, including those for the United States, are derived from a variety of sources. The ideal source of such information would be comprehensive evaluations that apply the same criteria to deposits in different geographic areas and report the results by country. In the absence of such evaluations, national reserves estimates compiled by countries for selected mineral commodities are a primary source of national reserves information. Lacking national assessment information by governments, sources such as academic articles, company reports, presentations by company representatives, and trade journal articles, or a combination of these, serve as the basis for national reserves information reported in the mineral commodity sections of this publication. A national estimate may be assembled from the following: historically reported reserves information carried for years without alteration because no new information is available; historically reported reserves reduced by the amount of historical production; and company reported reserves. International minerals availability studies conducted by the U.S. Bureau of Mines (USBM), before 1996, and estimates of identified resources by an international collaborative effort (the

  16. Why Mineral Interfaces Matter

    NASA Astrophysics Data System (ADS)

    Putnis, Andrew; Putnis, Christine V.

    2015-04-01

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

  17. MINER{nu}A Test Beam Commissioning

    SciTech Connect

    Higuera, A.; Castorena, J.; Urrutia, Z.; Felix, J.; Zavala, G.

    2009-12-17

    MINER{nu}A Main INjector ExpeRiment {nu}-A is a high-statistic neutrino scattering experiment that will ran in the NuMI Beam Hall at Fermilab. To calibrate the energy response of the MINER{nu}A detector, a beamline is being designed for the MINER{nu}A Test Beam Detector (TBD). The TBD is a replica of the full MINER{nu}A detector at small scale for calibration studies of the main detector. The beamline design consists of the following parts: a copper target, used to generate tertiaries from an incoming secondary beam; a steel collimator for tertiaries, which also serves as a dump for the incoming beam; a time of fight system (scintillator planes); four wire chambers, for angle measurements and tracking; and two dipole magnets, used as an spectrometer. During last October, the first commissioning run of the MINER{nu}A Test Beam took place in the Meson Test Beam Facility at Fermilab. We commissioned the target and collimator of the new tertiary beamline.

  18. Carbon dioxide sequestration by mineral carbonation

    SciTech Connect

    Gerdemann, Stephen J.; Dahlin David C.; O'Connor William K.; Penner Larry R.

    2003-11-01

    Concerns about global warming caused by the increasing concentration of carbon dioxide and other greenhouse gases in the earth’s atmosphere have resulted in the need for research to reduce or eliminate emissions of these gases. Carbonation of magnesium and calcium silicate minerals is one possible method to achieve this reduction. It is possible to carry out these reactions either in situ (storage underground and subsequent reaction with the host rock to trap CO2 as carbonate minerals) or ex situ (above ground in a more traditional chemical processing plant). Research at the Department of Energy’s Albany Research Center has explored both of these routes. This paper will explore parameters that affect the direct carbonation of magnesium silicate minerals serpentine (Mg3Si2O5(OH)4) and olivine (Mg2SiO4) to produce magnesite (MgCO3), as well as the calcium silicate mineral, wollastonite (CaSiO3), to form calcite (CaCO3). The Columbia River Basalt Group is a multi-layered basaltic lava plateau that has favorable mineralogy and structure for storage of CO2. Up to 25% combined concentration of Ca, Fe2+, and Mg cations could react to form carbonates and thus sequester large quantities of CO2. Core samples from the Columbia River Basalt Group were reacted in an autoclave for up to 2000 hours at temperatures and pressures to simulate in situ conditions. Changes in core porosity, secondary minerals, and solution chemistry were measured.

  19. 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.

  20. 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.

  1. Pathophysiology of chronic kidney disease-mineral and bone disorder.

    PubMed

    Mac Way, Fabrice; Lessard, Myriam; Lafage-Proust, Marie-Hélène

    2012-12-01

    Chronic kidney disease (CKD) alters the metabolism of several minerals, thereby inducing bone lesions and vessel-wall calcifications that can cause functional impairments and excess mortality. The histological bone abnormalities seen in CKD, known as renal osteodystrophy, consist of alterations in the bone turnover rate, which may be increased (osteitis fibrosa [OF]) or severely decreased (adynamic bone disease [AD]); abnormal mineralization (osteomalacia [OM]), and bone loss. Secondary hyperparathyroidism is related to early phosphate accumulation (responsible for FGF23 overproduction by bone tissue), decreased calcitriol production by the kidneys, and hypocalcemia. Secondary hyperparathyroidism is associated with OF. Other factors that affect bone include acidosis, chronic inflammation, nutritional deficiencies, and iatrogenic complications.

  2. 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.

  3. 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.

  4. Nontronite Mineralization in Columbia River Basalts

    NASA Astrophysics Data System (ADS)

    Baker, L.

    2015-12-01

    The ferric smectite nontronite is one of the first minerals formed by secondary weathering of Columbia River Basalts (CRB). Although nontronite is a common weathering product of CRB, it is not ubiquitous; field relations in near-surface flows suggest it only forms where sufficient water is available. In near-surface flows that are above the water table, nontronite is found filling cracks or vesicles, or in association with paleosols now preserved between flows in many localities. Field relations strongly suggest that porosity and permeability at the millimeter to meter scale control the supply of water for weathering and are key to the chemical composition of secondary clays and to the overall abundance of individual secondary weathering minerals. Weathering in the basalts initiates in void spaces that hold water, where high-Fe nontronite forms radiating acicular sprays. Small void spaces fill completely with nontronite of uniform composition, which penetrates the walls and replaces surrounding glass and ferromagnesian minerals. This process produces a relatively limited quantity of high-purity ferric nontronite. In large void spaces where water is limiting, nontronite lines the interior of vesicles but does not fill them; vermicular clay strands grow into the space from nucleation sites at the vesicle wall. Nontronitic cores are coated by layers of Mg- and Al-rich clays, and Mn oxides coat the exteriors. Thus, weathering under water-limited conditions appears to produce more compositionally complex mineral assemblages. In more extensively weathered basalts, nontronite is not present except in isolated, enclosed spaces. Results of this study may be useful in interpreting remotely sensed mineralogical data on Mars. The compositions of ferromagnesian smectites and spatial relationships between different clays on Mars may hold clues to the original conditions of water-rock interaction.

  5. Mineral resources of Antarctica

    USGS Publications Warehouse

    Compiled and edited by Wright, Nancy A.; Williams, Paul L.

    1974-01-01

    Although the existence of mineral deposits in Antarctica is highly probable, the chances of finding them are quite small. Minerals have been found there in great variety but only as occurrences. Manganese nodules, water (as ice), geothermal energy, coal, petroleum, and natural gas are potential resources that could perhaps be exploited in the future. On the basis of known mineral occurrences in Antarctica and relationships between geologic provinces of Antarctica and those of neighboring Gondwana continents, the best discovery probability for a base-metal deposit in any part of Antarctica is in the Andean orogen; it is estimated to be 0.075 (75 chances in 1,000).

  6. Definitions of Health Terms: Minerals

    MedlinePlus

    ... gov/definitions/mineralsdefinitions.html Definitions of Health Terms : Minerals To use the sharing features on this page, ... National Institutes of Health, Office of Dietary Supplements Minerals Minerals are those elements on the earth and ...

  7. Biological Control on Mineral Transformation in Soils ?

    NASA Astrophysics Data System (ADS)

    Ziegler, K.; Hsieh, J. C.; Chadwick, O. A.; Kelly, E. F.

    2001-12-01

    Weathering of primary minerals is commonly linked to biological processes through the production of carbonic and organic acids. Plants can also play a role in weathering by removing soluble constituents and enhancing diffusion gradients within the soil. Here we investigate the synthesis of secondary minerals and the role of plants in removing elements that act as building blocks for these minerals. In order to minimize losses from leaching, we have sampled a chronosequence of soils forming on lava flows on Hawaii Island that receive about 200 mm of rain annually and have never been subjected to high levels of rainfall. The P concentration in the soils drops from almost 3000 mg/kg on a 1.5 ky lava flow to around 1000 mg/kg on a 350 ky lava flow. This loss of P can only be ascribed to P-uptake by plants with subsequent removal through the loss of above ground biomass through fire and/or wind removal. Over the same time frame the amount of plagioclase in the soils drops from around 22% of the <2 mm soil fraction on the youngest lava flow to virtually 0% on the 350 ky flow, suggesting a substantial release of Si. Elevated silicon in arid, basaltic soil environments often leads to formation of smectite, a feature not observed along the chronosequence. In fact, plagioclase is replaced by the kaolin mineral halloysite with allophane as an apparent precursor. Kaolin minerals are associated with moderate to intense leaching environments rather than the mild leaching conditions that influence these soils. We selected an intermediate age soil profile (170 ky lava flow) to conduct an in-depth investigation of the soil mineral composition. We detected a strong dominance of halloysite, the presence of gibbsite, but no smectite. Secondary halloysite formation is preferred over smectite formation when Si activities are relatively low, and the pH is acidic rather than alkaline. Although this mineral assemblage seems to imply formation under a wetter climatic regime, the oxygen

  8. 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.

  9. Vitamins and Minerals

    MedlinePlus

    ... Also, many nutrients interact with each other. Most nutritionists believe in designing an overall program of supplements. ... SUPPLEMENTS? In addition to vitamins and minerals, some nutritionists suggest that people with HIV take supplements of ...

  10. Identification of Mineral Phases on Basalt Surfaces by Imaging SIMS.

    PubMed

    Ingram, J C; Groenewold, G S; Olson, J E; Gianotto, A K; McCurry, M O

    1999-05-01

    A method for the identification of mineral phases on basalt surfaces utilizing secondary ion mass spectrometry (SIMS) with imaging capability is described. The goal of this work is to establish the use of imaging SIMS for characterization of the surface of basalt. The basalt surfaces were examined by interrogating the intact basalt (heterogeneous mix of mineral phases) as well as mineral phases that have been separated from the basalt samples. Mineral separates from the basalt were used to establish reference spectra for the specific mineral phases. Electron microprobe and X-ray photoelectron spectroscopy were used as supplemental techniques for providing additional characterization of the basalt. Mineral phases that make up the composition of the basalt were identified from single-ion images which were statistically grouped. The statistical grouping is performed by utilizing a program that employs a generalized learning vector quantization technique. Identification of the mineral phases on the basalt surface is achieved by comparing the mass spectra from the statistically grouped regions of the basalt to the mass spectral results from the mineral separates. The results of this work illustrate the potential for using imaging SIMS to study adsorption chemistry at the top surface of heterogeneous mineral samples.

  11. 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

  12. Clay Minerals: Adsorbophysical Properties

    NASA Astrophysics Data System (ADS)

    Kotova, O.

    2013-12-01

    The structure and features of surfaces of clay minerals (kaolin, montmorillonite, etc) have an important scientific and practical value. On the surface the interrelation of processes at electronic, atomic and molecular levels is realized. Availability of mineral surface to external influences opens wide scientific and technical opportunities of use of the surface phenomena, so the research of crystal-chemical and crystal-physical processes in near-surface area of clay minerals is important. After long term researches of gas-clay mineral system in physical fields the author has obtained experimental and theoretical material contributing to the creation of the surface theory of clays. A part of the researches is dedicated to studying the mechanism of crystal-chemical and crystal-physical processes in near surface area of clay mineral systems, selectivity of the surface centers to interact with gas phase molecules and adsorbophysical properties. The study of physical and chemical properties of fine clay minerals and their modification has a decisive importance for development of theory and practice of nanotechnologies: they are sorbents, membranes, ceramics and other materials with required electronic features.

  13. 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.

  14. 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.

  15. 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.

  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. Evaluation of Water-Mineral Interaction Using Microfluidic Tests with Thin Sections

    NASA Astrophysics Data System (ADS)

    Oh, Y. S.; Ryu, J. H.; Koh, Y. K.; Jo, H. Y.

    2014-12-01

    For the geological disposal of radioactive wastes, geological settings and groundwater conditions are significantly important because of their effects on a radionuclide migration. One of the preferred host rocks for the radioactive waste disposal is crystalline rock. Fractures in crystalline rocks are main fluid pathways. Groundwater reacts with fracture filling minerals in fracture zones, resulting in physicochemical changes in the minerals and groundwater. In this study, fracture filling mineral-groundwater interactions were investigated by conducting microfluidic tests using thin sections at various conditions (i.e., fluid chemistry and flow rate). Groundwater and rock core samples collected from the KAERI Underground Research Tunnel (KURT) located in the Korea Atomic Energy Research Institute (KAERI) were used in this study. Dominant bedrock is two-mica granite, which contains both biotite and muscovite. Secondary minerals (e.g., chlorite, calcite and clay minerals) occur in fracture and alteration zones. In nature, water-mineral interactions generally take long time. Microfluidic tests were conducted to simulate water-mineral interactions in shorter time with smaller scale. Thin sections of fracture filling minerals, minerals from alteration zones, and natural and synthetic groundwater samples were used for the microfluidic tests. Results showed that water-mineral interactions at various conditions caused changes in groundwater chemistry, dissolution of minerals, precipitation of secondary minerals, and formation of colloids, which can affect radionuclide migration. In addition, the fluid chemistry and flow rate affected characteristics of water-rock interactions.

  18. 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.

  19. 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.

  20. 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.

  1. 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.

  2. 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.

  3. 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…

  4. 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.”

  5. Nitrogen mineralization and assimilation at millimeter scales.

    PubMed

    Myrold, David D; Pett-Ridge, Jennifer; Bottomley, Peter J

    2011-01-01

    The assimilation (uptake or immobilization) of inorganic nitrogen (N) and the production of ammonium (NH(4)(+)) from organic N compounds are universal functions of microorganisms, and the balance between these two processes is tightly regulated by the relative demands of microbes for N and carbon (C). In a heterogeneous environment, such as soils, bulk measurements of N mineralization or immobilization do not reflect the variation of these two processes in different microhabitats (1μm-1mm). Our purpose is to review the approaches that can be applied to measure N mineralization and immobilization within soil microhabitats, at scales of millimeter (using adaptations of (15)N isotope pool dilution and IRMS-isotope ratio mass spectrometry) to micrometer (using SIMS-secondary ion mass spectrometry). PMID:21514461

  6. Green Clay Minerals

    NASA Astrophysics Data System (ADS)

    Velde, B.

    2003-12-01

    Color is a problem for scientific study. One aspect is the vocabulary one used to describe color. Mint green, bottle green, and Kelly green are nice names but not of great utility in that people's physical perception of color is not always the same. In some industries, such as colored fabric manufacture, current use is to send a set of standard colors which are matched by the producer. This is similar to the use of the Munsell color charts in geology. None of these processes makes use of physical optical spectral studies. The reason is that they are difficult to obtain and interpret. For a geologist, color is very important but we rarely have the possibility to standardize the method of our color perception. One reason is that color is both a reflective and transmission phenomenon. The thickness of the sample is critical to any transmission characteristics. Hence, a field color determination is different from one made by using a petrographic microscope. Green glauconite in a hand specimen is not the same color in 30 μm thick thin section seen with a microscope using transmitted light.A second problem is that color in a spectral identification is the result of several absorption emissions,with overlapping signal, forming a complicated spectrum. Interpretation depends very greatly on the spectrum of the light source and the conditions of transmission-reflection of the sample. As a result, for this text, we will not attempt to analyze the physical aspect of green in green clays. In the discussion which follows, reference is made concerning color, to thin section microscopic perception.Very briefly, green clay minerals are green, because they contain iron. This is perhaps not a great revelation to mineralogists, but it is the key to understanding the origin and stability of green clay minerals. In fact, iron can color minerals either red or green or in various shades of orange and brown. The color most likely depends upon the relative abundance of the iron ion valence

  7. 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

  8. 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.

  9. [Soil nitrogen mineralization under different land use patterns in Xishuangbanna].

    PubMed

    Li, Mingrui; Sha, Liqing

    2005-01-01

    Nitrogen (N) cycle is very important for forest ecosystem, and soil N mineralization rate is often used as the index of soil N availability and its losses. Using Close-Top incubation method, we measured the N mineralization rate in soils (0-15 cm) of monsoon evergreen broadleaf forest, seasonal rain forest, rubber plantation, heavily disturbed seasonal rain forest, Millettia laptobotrya secondary forest and upland rice field. The results showed that the net N mineralization rate and N nitrification rate were decreased in the sequence of heavily disturbed seasonal rain forest > Millettia laptobotrya secondary forest > seasonal rain forest > monsoon evergreen broadleaf forest > rubber plantation > upland rice field. Rubber plantation and upland rice field were the most seriously disturbed land use patterns. Their soil N storage and mineralization rate were very low and exhibited significant variations, compared with other land use patterns. Lower net N mineralization rate correlated with lower N storage, and also, with lower fungi numbers. The N mineralization rate in disturbed forest soil which had recovered for several years was similar to that in primary forest soil, but decreased significantly when the forests were converted to agricultural land.

  10. Oxalate minerals on Mars?

    NASA Astrophysics Data System (ADS)

    Applin, D. M.; Izawa, M. R. M.; Cloutis, E. A.; Goltz, D.; Johnson, J. R.

    2015-06-01

    Small amounts of unidentified organic compounds have only recently been inferred on Mars despite strong reasons to expect significant concentrations and decades of searching. Based on X-ray diffraction and reflectance spectroscopic analyses we show that solid oxalic acid and its most common mineral salts are stable under the pressure and ultraviolet irradiation environment of the surface of Mars, and could represent a heretofore largely overlooked reservoir of organic carbon in the martian near-surface. In addition to the delivery to Mars by carbonaceous chondrites, oxalate minerals are among the predicted breakdown products of meteoritic organic matter delivered to the martian surface, as well as any endogenic organic carbon reaching the martian surface from the interior. A reinterpretation of pyrolysis experiments from the Viking, Phoenix, and Mars Science Laboratory missions shows that all are consistent with the presence of significant concentrations of oxalate minerals. Oxalate minerals could be important in numerous martian geochemical processes, including acting as a possible nitrogen sink (as ammonium oxalate), and contributing to the formation of “organic” carbonates, methane, and hydroxyl radicals.

  11. Marine mineral resources

    SciTech Connect

    Fillmore, E.

    1990-01-01

    This book includes the following topics: law of the sea; minerals of the deep seabed; placers and subseabed metallics; industrial chemical materials and coal; the United State exclusive economic zone: the management challenge; and the United Kingdom and Norway: offshore petroleum development policies.

  12. Bioleaching of Minerals

    SciTech Connect

    F. Roberto

    2002-02-01

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

  13. Oxidants from Pulverized Minerals

    NASA Astrophysics Data System (ADS)

    Martel, L. M. V.

    2007-06-01

    Joel Hurowitz (previously at State University of New York at Stony Brook and now at the Jet Propulsion Laboratory), Nick Tosca, Scott McLennan, and Martin Schoonen (SUNY at Stony Brook) studied the production of hydrogen peroxide from freshly pulverized minerals in solution. Their experiments focused on olivine, augite, and labradorite; silicate minerals of basaltic planetary surfaces, such as the Moon and Mars, that are exposed to the intense crushing and grinding of impact cratering processes. The hydrogen peroxide produced in the experiments was enough to adequately explain the oxidizing nature of Martian regolith first determined by the Viking Landers and the results suggest, for the first time, that mechanically activated mineral surfaces may be an important part of the overall explanation for the Viking Lander biology experiment results. Hurowitz and coauthors further showed that when the pulverized minerals are heat-treated to high temperature under vacuum (to cause dehydroxylation) there is almost a 20 times increase in hydrogen peroxide production, a result which may be highly relevant to lunar dust. These careful studies demonstrate the importance of and concern about reactive dusts on planetary surfaces from two standpoints: the health of astronauts on surface maneuvers who may inadvertently breath it and the viability of possible Martian organic species to survive in such a corrosive, antiseptic surface environment.

  14. 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…

  15. Clay Mineral: Radiological Characterization

    NASA Astrophysics Data System (ADS)

    Cotomácio, J. G.; Silva, P. S. C.; Mazzilli, B. P.

    2008-08-01

    Since the early days, clays have been used for therapeutic purposes. Nowadays, most minerals applied as anti-inflammatory, pharmaceutics and cosmetic are the clay minerals that are used as the active ingredient or, as the excipient, in formulations. Although their large use, few information is available in literature on the content of the radionuclide concentrations of uranium and thorium natural series and 40K in these clay minerals. The objective of this work is to determine the concentrations of 238U, 232Th, 226Ra, 228Ra, 210Pb and 40K in commercial samples of clay minerals used for pharmaceutical or cosmetic purposes. Two kinds of clays samples were obtained in pharmacies, named green clay and white clay. Measurement for the determination of 238U and 232Th activity concentration was made by alpha spectrometry and gamma spectrometry was used for 226Ra, 228Ra, 210Pb and 40K determination. Some physical-chemical parameters were also determined as organic carbon and pH. The average activity concentration obtained was 906±340 Bq kg-1 for 40K, 40±9 Bq kg-1 for 226Ra, 75±9 Bq kg-1 for 228Ra, 197±38 Bq kg-1 for 210Pb, 51±26 Bq kg-1 for 238U and 55±24 Bq kg-1 for 232Th, considering both kinds of clay.

  16. Linking Home Plate and Algonquin Class Rocks through Microtextural Analysis: Evidence for Hydrovolcanism in the Inner Basin of Columbia Hills, Gusev Crater

    NASA Technical Reports Server (NTRS)

    Mittlefehldt, David W.; Yingst, R. Aileen; Schmidt, Mariek E.; Herkenhoff, Ken E.

    2007-01-01

    Examining the his-tory of a rock as the summed history of its constituent grains is a proven and powerful strategy that has been used on Earth to maximize the information that can be gleaned from limited samples. Grain size, sorting, roundness, and texture can be observed at the handlens scale, and may reveal clues to transport regime (e.g. fluvial, glacial, eolian) and transport distance. Diagenetic minerals may be of a form and textural context to allow identification, and to point to dominant diagenetic processes (e.g. evaporitic concentration, intermittent dissolution, early vs. late diagenetic emplacement). Handlens scale features of volcaniclastic particles may be diagnostic of primary vs recycled (by surface processes) grains and may provide information about eruptive patterns and processes. When the study site is truly remote, such as Mars, and when there are severe limitations on sample return or sample analysis with other methods, examination at the hand lens scale becomes critical both for extracting a maximum of information, and for best utilizing finite analytical capabilities.

  17. 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.

  18. Isotopic bone mineralization rates in maintenance dialysis patients

    SciTech Connect

    Cochran, M.; Stephens, E.

    1983-09-01

    The expanding pool model of radiocalcium kinetics has been used in 13 maintenance dialysis patients to measure bone mineralization rate. No difficulties were met in applying the data to the model, and values for the bone mineralization rate ranged from 0.0 to 2.0 mmol/kg Ca++ per day. The bone histology obtained at the time of the study showed a correlation between the degree of secondary hyperparathyroidism and the bone mineralization rate, with low values of the latter occurring in atypical osteomalacia (two patients) or inactive-looking bone (one patient) and raised values in seven patients. The plasma alkaline phosphatase and immunoassayable parathyroid hormone levels each correlated significantly with the bone mineralization rate. These findings suggest that the technique is valid when applied to hemodialysis patients and provides quantitative information about skeletal calcium metabolism in different types of renal bone disease.

  19. Mercury from mineral deposits and potential environmental impact

    USGS Publications Warehouse

    Rytuba, J.J.

    2003-01-01

    Mercury deposits are globally distributed in 26 mercury mineral belts. Three types of mercury deposits occur in these belts: silica-carbonate, hot-spring, and Almaden. Mercury is also produced as a by-product from several types of gold-silver and massive sulfide deposits, which account for 5% of the world's production. Other types of mineral deposits can be enriched in mercury and mercury phases present are dependent on deposit type. During processing of mercury ores, secondary mercury phases form and accumulate in mine wastes. These phases are more soluble than cinnabar, the primary ore mineral, and cause mercury deposits to impact the environment more so than other types of ore deposits enriched in mercury. Release and transport of mercury from mine wastes occur primarily as mercury-enriched particles and colloids. Production from mercury deposits has decreased because of environmental concerns, but by-product production from other mercury-enriched mineral deposits remains important.

  20. Engineering of Secondary Metabolism.

    PubMed

    O'Connor, Sarah E

    2015-01-01

    Secondary (specialized) metabolites, produced by bacteria, fungi, plants, and other organisms, exhibit enormous structural variation, and consequently display a wide range of biological activities. Secondary metabolism improves and modulates the phenotype of the host producer. Furthermore, these biological activities have resulted in the use of secondary metabolites in a variety of industrial and pharmaceutical applications. Metabolic engineering presents a powerful strategy to improve access to these valuable molecules. A critical overview of engineering approaches in secondary metabolism is presented, both in heterologous and native hosts. The recognition of the increasing role of compartmentalization in metabolic engineering is highlighted. Engineering approaches to modify the structure of key secondary metabolite classes are also critically evaluated.

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

    NASA Astrophysics Data System (ADS)

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

    2015-12-01

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

  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. 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.

  4. 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.

  5. Secondary power systems

    SciTech Connect

    Not Available

    1985-01-01

    In aeronautical engineering secondary power systems have long played second fiddle to the airframe, the engine, and indeed, the avionics. This collection of papers is thus timely, and its publication by the Institution of Mechanical Engineers appropriate, as secondary power systems in modern aircraft present challenging mechanical engineering problems. In military aircraft demands for electrical and hydraulic power and high pressure air have grown over the past two decades. To these basic needs are added requirements for emergency power, ground power, and independent engine starting. Additionally increased reliability and maintainability is demanded from all secondary power systems. Complete contents: What is a secondary power system. Modern technology secondary power systems for next generation military aircraft; Integrated power units; Secondary power system gearbox; Starting the system - air turbine starters; Auxiliary and emergency power system; Secondary hydraulic power generation; Advanced technology electrical power generation equipment.

  6. 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.

  7. 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.

  8. Minerals and mine drainage

    SciTech Connect

    Liang, H.C.; Thomson, B.M.

    2009-09-15

    A review of literature published in 2008 and early 2009 on research related to the production of acid mine drainage and/or in the dissolution of minerals as a result of mining, with special emphasis on the effects of these phenomena on the water quality in the surrounding environment, is presented. This review is divided into six sections: 1) Site Characterization and Assessment, 2) Protection, Prevention, and Restoration, 3) Toxicity Assessment, 4) Environmental Fate and Transport, 5) Biological Characterization, and 6) Treatment Technologies. Because there is much overlap in research areas associated with minerals and mine drainage, many papers presented in this review can be classified into more than one category, and the six sections should not be regarded as being mutually-exclusive, nor should they be thought of as being all-inclusive.

  9. 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.

  10. Salton sea minerals

    NASA Astrophysics Data System (ADS)

    Bell, Peter M.

    The long-held notion that precious metals, minerals, and other useful substances can be extracted from natural waters is starting to become realized at several locations of geothermal brines. In a recent study by A. Maimoni of the Lawrence Livermore National Laboratory it was determined that there is a high potential for minerals recovery from the hot brines of a 1000-MWe geothermal power station at the Salton Sea geothermal field in southern California. The study estimated that the revenue from the minerals could substantially exceed that from the power station (Geothermics, 11, 239-258, 1982).According to the study, ‘A 1000-MWe power plant could recover 14-31% of the U.S. demand for manganese.’ In the example of lithium production, such a geothermal plant could produce 5-10 times the annual world output of lithium. Large quantities of lead and zinc could be extracted, as well as significant amounts of gold, platinum, and silver. The chemical composition of the brines is incredibly complex, however, for reasons not currently understood.

  11. Clay Mineral Preferred Orientation

    NASA Astrophysics Data System (ADS)

    Day-Stirrat, R. J.

    2014-12-01

    Anisotropy of the orientation of clay minerals, often referred to as texture, may be unique to sediments' deposition, composition, deformation or diagenetic history. The literature is rich with studies that include preferred orientation generation in fault gouge, low-grade metamorphic rocks, sediments with variable clay content and during the smectite-to-illite transformation. Untangling the interplay between many competing factors in any one geologic situation has proven a significant challenge over many years. Understanding how, where and when clay minerals develop a preferred orientation has significant implications for permeability anisotropy in shallow burial, the way mechanical properties are projected from shallower to deeper settings in basin modeling packages and the way velocity anisotropy is accounted for in seismic data processing. The assessment of the anisotropic properties of fine-grained siliciclastic rocks is gaining significant momentum in rock physics research. Therefore, a fundamental understanding of how clay minerals develop a preferred orientation in space and time is crucial to the understanding of anisotropy of physical properties. The current study brings together a wealth of data that may be used in a predictive sense to account for fabric anisotropy that may impact any number of rock properties.

  12. Who's on First? Part II: Bacterial and fungal colonization of fresh soil minerals

    NASA Astrophysics Data System (ADS)

    Whitman, T.; Neurath, R.; Zhang, P.; Yuan, T.; Weber, P. K.; Zhou, J.; Pett-Ridge, J.; Firestone, M. K.

    2015-12-01

    Soil organic matter (SOM) stabilization by soil minerals is an important mechanism influencing soil C cycling. Microbes make up only a few percent of total SOM, but have a disproportionate impact on SOM cycling. Their direct interactions with soil minerals, however, are not well characterized. We studied colonization of fresh minerals by soil microbes in an Avena barbata (wild oat) California grassland soil microcosm. Examining quartz, ferrihydrite, kaolinite, and the heavy fraction of the native soil, we asked: (1) Do different minerals select for different communities, or do random processes drive the colonization of fresh minerals? (2) What factors influence which taxa colonize fresh minerals? After incubating mesh bags (<18 μm) of minerals buried next to actively growing plant roots for 2 months, we used high-throughput sequencing of 16S and ITS2 genes to characterize the microbial communities colonizing the minerals. We found significant differences between the microbial community composition of different minerals and soil for both bacteria and fungi. We found a higher relative abundance of arbuscular mycorrhial fungi with ferrihydrite and quartz, and nanoscale secondary ion mass spectrometry (NanoSIMS) imaging of these minerals suggests that some fungal hyphae are moving C directly from roots to mineral surfaces. The enriched presence of both nematode-associated fungi (Pochonia sp.) and bacteria (Candidatus Xiphinematobacter) in the minerals suggests that these minerals may be a habitat for nematodes. Bacteria of the family Chitinophagaceae and genus Janthinobacterium were significantly enriched on both ferrihydrite and quartz minerals, both of which may interact with colonizing fungi. These findings suggest that: (1) Microbial colonization of fresh minerals is not a fully passive or neutral process. (2) Mineral exploration by plant-associated fungi and soil fauna transport may be factors in determining the initial colonization of minerals and subsequent C

  13. 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

  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. Recognition of coseismic-related microstructures and behaviour of clay minerals within the core of active fault

    NASA Astrophysics Data System (ADS)

    Buatier, M.; Chauvet, A.; Ritz, J.; Jolivet, M.; Bayarjargal, B.; Vitalie, M.; Vassalo, R.

    2008-12-01

    Seismogenic faults are commonly characterized by a zonation with foliated gouge and breccias surrounded by damage zone. This zonation results from co-seismic or inter-seismic deformation and fluid-rock interactions. Based on field, textural, microtextural and clay mineralogical analysis, the core zone of an active fault located in the Bogd Mongolian massif has been studied. This fault is supposed to be an ancient major ductile shear zone re-activated during the Quaternary. Field studies reveal the complexity of the fault cores with the association between fragmented/ brecciated domains and at least two generations of gouge. The first gouge presents a foliated structure. The second one is characterized by an homogeneous black, thin, fine-grained, gouge. According to field constraints, the thin gouge level can correspond to the last seismic event. Catholuminescence and SEM investigations allow to characterize the texture of each gouge and surrounding rocks. Additional measurement of grain size distribution, grain circularity, grain shape and grain fabrics allow the clear distinction between the two different gouge textures: foliated and isotropic. In the foliated gouge, mineralogical study (SEM-BSE and DRX) displays evidence of fluid-rock interactions with alteration of micas to illite/smectite and formation of kaolinite. The presence of authigenic gypsum crystals and Fe-oxyhydroxyde suggests interseismic fluid circulation in this permeable structure. The last generation of gouge with isotropic texture is clay rich and is characterized by the presence of smectite (hydrated clay mineral). The data suggest polyphase deformation with ductile structures associated with brittle deformation implying communition process. The debate concerns the mode of formation of the gouge and the origin of clay minerals.

  17. Advances in Raman spectroscopy for In Situ Identification of Minerals and Organics on Diverse Planetary Surfaces: from Mars to Titan

    NASA Astrophysics Data System (ADS)

    Blacksberg, J.; Alerstam, E.; Maruyama, Y.; Cochrane, C.; Rossman, G. R.

    2015-12-01

    We present recent developments in time-resolved Raman spectroscopy for in situ planetary surface exploration, aimed at identification of both minerals and organics. Raman is a non-destructive surface technique that requires no sample preparation. Raman spectra are highly material specific and can be used for identification of a wide range of unknown samples. In combination with micro-scale imaging and point mapping, Raman spectroscopy can be used to directly interrogate rocks and regolith materials, while placing compositional analyses within a microtextural context, essential for understanding surface evolutionary pathways. Due to these unique capabilities, Raman spectroscopy is of great interest for the exploration of all rocky and icy bodies, for example Mars, Venus, the Moon, Mars' moons, asteroids, comets, Europa, and Titan. In this work, we focus on overcoming one of the most difficult challenges faced in Raman spectroscopy: interference from background fluorescence of the very minerals and organics that we wish to characterize. To tackle this problem we use time-resolved Raman spectroscopy, which separates the Raman from background processes in the time domain. This same technique also enables operation in daylight without the need for light shielding. Two key components are essential for the success of this technique: a fast solid-state detector and a short-pulse laser. Our detector is a custom developed Single Photon Avalanche Diode (SPAD) array, capable of sub-ns time-gating. Our pulsed lasers are solid-state miniature pulsed microchip lasers. We discuss optimization of laser and detector parameters for our application. We then present Raman spectra of particularly challenging planetary analog samples to demonstrate the unique capabilities of this time-resolved Raman instrument, for example, Mars-analog clays and Titan-analog organics. The research described here was carried out at the Jet Propulsion Laboratory, California Institute of Technology, under a

  18. DIAMOND SECONDARY EMITTER

    SciTech Connect

    BEN-ZVI, I.; RAO, T.; BURRILL, A.; CHANG, X.; GRIMES, J.; RANK, J.; SEGALOV, Z.; SMEDLEY, J.

    2005-10-09

    We present the design and experimental progress on the diamond secondary emitter as an electron source for high average power injectors. The design criteria for average currents up to 1 A and charge up to 20 nC are established. Secondary Electron Yield (SEY) exceeding 200 in transmission mode and 50 in emission mode have been measured. Preliminary results on the design and fabrication of the self contained capsule with primary electron source and secondary electron emitter will also be presented.

  19. Platinum mineralization in the Kapalagulu Intrusion, western Tanzania

    NASA Astrophysics Data System (ADS)

    Wilhelmij, Harry R.; Cabri, Louis J.

    2016-03-01

    . Impersistent, stratiform PGE mineralized horizons occur within the MCSS harzburgite from which drill core samples were taken for platinum-group mineral (PGM) characterization from two drill holes. Where the PGE reefs reach the surface there is residual PGE mineralization within the laterite regolith from which drill core samples were taken from various laterite lithological units for PGM characterization. As the harzburgite PGE reefs contain significant concentrations of both sulfide and chromite (including chromitite seams) they resemble the PGE-rich chromitite seams of the Bushveld Complex rather than the PGE-bearing Main Sulfide Zone of the Great Dyke and Main Sulfide Layer of the Munni Munni Complex. The dominant Pd PGM in three PGE reef samples varies, ranging ( n = 164, relative wt%) from bismuthides (63 %), bismuthtellurides (19 %), and tellurides (6 %), to tellurides (39 %), bismuthtellurides (24 %), stannides (14 %), and alloys (13 %), and to antimon-arsenides (33 %), stannides (21 %), bismuthides (17 %), tellurides (13 %), and alloys (10 %). From 13.5 % to 21.0 % of the total Pd occurs as a solid solution in pentlandite. The three samples have similar Pt PGM modal distributions ( n = 172, relative wt%); the dominant Pt mineral is sperrylite (79, 58, and 47 %) followed by tellurides (15, 17, 21 %), alloys (2, 1, 1 %), and sulfides (2, 1, 0 %). Comparison of Pd/Pt ratios from assays to those calculated from minerals show that the data for the Pt and Pd PGM are very robust, confirming the concentration methodology and characterization. Study of samples from a shallow drill hole penetrating the laterite regolith shows that the primary Pd mineralization has not survived oxidation, is mainly dispersed, but some was reconstituted to form secondary minerals: cabriite, unnamed tellurides, a selenide, a Pd-Te-Hg mineral, alloys and Pd-bearing secondary sulfides (millerite and heazlewoodite). The primary Pt minerals are more resistant to oxidation and dissolution, especially

  20. 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. PMID:24610728

  1. Secondary HIV prevention.

    PubMed

    Temoshok, L R; Frerichs, R R

    1998-06-01

    Primary HIV prevention, preventing HIV exposure among uninfected persons, has been the focus of much attention. However, secondary HIV prevention, preventing HIV transmission from infected people to their uninfected contacts, has not received as much interest or attention from HIV researchers, clinicians, and policymakers. The concept of secondary HIV prevention, as distinguished from primary prevention, is clarified, and the current and future strategies to further secondary HIV prevention efforts are explored. Secondary prevention strategies can be incorporated into comprehensive programs and result in shifts in attitudes and behaviors. This could reduce the size of the epidemic, while also benefiting the individual and his or her close relationships.

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

    Code of Federal Regulations, 2014 CFR

    2014-10-01

    .... 2 of 43 CFR, which appears in Volume II of the List of CFR Sections Affected, 1964-1972, for the... 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:...

  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

    .... 2 of 43 CFR, which appears in Volume II of the List of CFR Sections Affected, 1964-1972, for the... 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:...

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

    Code of Federal Regulations, 2012 CFR

    2012-10-01

    .... 2 of 43 CFR, which appears in Volume II of the List of CFR Sections Affected, 1964-1972, for the... 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:...

  5. 43 CFR 19.8 - Prospecting, mineral locations, mineral patents, and mineral leasing within National Forest...

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    .... 2 of 43 CFR, which appears in Volume II of the List of CFR Sections Affected, 1964-1972, for the... 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:...

  6. 43 CFR 19.8 - Prospecting, mineral locations, mineral patents, and mineral leasing within National Forest...

    Code of Federal Regulations, 2011 CFR

    2011-10-01

    .... 2 of 43 CFR, which appears in Volume II of the List of CFR Sections Affected, 1964-1972, for the... 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:...

  7. Water, mineral waters and health.

    PubMed

    Petraccia, Luisa; Liberati, Giovanna; Masciullo, Stefano Giuseppe; Grassi, Marcello; Fraioli, Antonio

    2006-06-01

    The authors focus on water resources and the use of mineral waters in human nutrition, especially in the different stages of life, in physical activity and in the presence of some morbid conditions. Mineral water is characterized by its purity at source, its content in minerals, trace elements and other constituents, its conservation and its healing properties recognized by the Ministry of Health after clinical and pharmacological trials. Based on total salt content in grams after evaporation of 1l mineral water dried at 180 degrees C (dry residues), mineral waters can be classified as: waters with a very low mineral content, waters low in mineral content, waters with a medium mineral content, and strongly mineralized waters. Based on ion composition mineral waters can be classified as: bicarbonate waters, sulfate waters, sodium chloride or saltwater, sulfuric waters. Based on biological activity mineral waters can be classified as: diuretic waters, cathartic waters, waters with antiphlogistic properties. Instructions for use, doses, and current regulations are included.

  8. 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.

  9. 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

  10. Hearing protection for miners

    SciTech Connect

    Schulz, T.

    2008-10-15

    A NIOSH analysis showed that at age 50 approximately 90% of coal miners have a hearing impairment, yet noise included hearing loss is 100% preventable. The article discusses requirements of the MSHA regulations, 30 CFR Part 62 - occupational noise exposure (2000) and a 2008-MSHA document describing technologically achievable and promising controls for several types of mining machinery. Hearing protection is still required for exposure to greater than 90 dBA. These are now commercially available ways to determine how much attenuation an individual gets from a given hearing protector, known as 'fit testing'. 3 refs., 1 fig., 1 tab., 1 photo.

  11. Mineral industries of the USSR - 1990

    SciTech Connect

    Not Available

    1991-01-01

    The report discusses mainly the mineral industries in the USSR, with a small section included concerning the mineral industries of Poland. Topics discussed include labor, foreign trade, metals, non-metallic minerals, and mineral fuels.

  12. Secondary Education Transition Model.

    ERIC Educational Resources Information Center

    Colorado State Univ., Ft. Collins.

    The Secondary Education Transition Model project at Colorado State University-Fort Collins represents a local and state commitment to serve students with severe handicaps who are moving into community work and living roles. These comprehensive transition services begin at the secondary education level and extend into the adult service system. The…

  13. Secondary fuel delivery system

    DOEpatents

    Parker, David M.; Cai, Weidong; Garan, Daniel W.; Harris, Arthur J.

    2010-02-23

    A secondary fuel delivery system for delivering a secondary stream of fuel and/or diluent to a secondary combustion zone located in the transition piece of a combustion engine, downstream of the engine primary combustion region is disclosed. The system includes a manifold formed integral to, and surrounding a portion of, the transition piece, a manifold inlet port, and a collection of injection nozzles. A flowsleeve augments fuel/diluent flow velocity and improves the system cooling effectiveness. Passive cooling elements, including effusion cooling holes located within the transition boundary and thermal-stress-dissipating gaps that resist thermal stress accumulation, provide supplemental heat dissipation in key areas. The system delivers a secondary fuel/diluent mixture to a secondary combustion zone located along the length of the transition piece, while reducing the impact of elevated vibration levels found within the transition piece and avoiding the heat dissipation difficulties often associated with traditional vibration reduction methods.

  14. Evaluating Mineral-Associated Soil Organic Matter Pools as Indicators of Forest Harvesting Disturbance

    NASA Astrophysics Data System (ADS)

    Kellman, L. M.; Gabriel, C. E.

    2015-12-01

    Soil organic matter (SOM) in northern forest soils is associated with a suite of minerals that can confer SOM stability, resulting in the potential for long-term storage of carbon. Increasingly, evidence is suggesting that SOM in certain mineral phases is dynamic and vulnerable to soil disturbance. The objective of this research was to investigate changes in a suite of mineral-associated pools of SOM through depth in a temperate forest soil to determine which mineral-associated carbon pools are most sensitive to forest harvesting disturbance. Sequential selective dissolutions representing increasingly stable SOM pools (soluble minerals (deionized water); humus-mineral complexes (Na-pyrophosphate); poorly crystalline minerals (HCl hydroxylamine); and crystalline secondary minerals (Na-dithionite + HCl)) of mineral soils through depth to 50 cm were carried out in podzolic soils sampled from temperate red spruce forests of contrasting stand age in Nova Scotia, Canada. Results of this analysis point to a loss of carbon from SOM within the B-horizon of the most recently harvested site from the pyrophosphate-extracted humus mineral complexed SOM, suggesting that it is this exchangeable pool that appears to be destabilized following clearcut harvesting at these study sites. This suggests that recovery from this landuse disturbance is dependent upon increasing storage of this SOM pool, and that mineral-associated pools, particularly pyrophosphate-extractable SOM, may be a useful indicator of changes to soil carbon storage following land use change.

  15. Spectroscopic characterization of manganese minerals.

    PubMed

    Lakshmi Reddy, S; Padma Suvarna, K; Udayabhaska Reddy, G; Endo, Tamio; Frost, R L

    2014-01-01

    Manganese minerals ardenite, alleghanyite and leucopoenicite originated from Madhya Pradesh, India, Nagano prefecture Japan, Sussex Country and Parker Shaft Franklin, Sussex Country, New Jersey respectively are used in the present work. In these minerals manganese is the major constituent and iron if present is in traces only. An EPR study of on all of the above samples confirms the presence of Mn(II) with g around 2.0. Optical absorption spectrum of the mineral alleghanyite indicates that Mn(II) is present in two different octahedral sites and in leucophoenicite Mn(II) is also in octahedral geometry. Ardenite mineral gives only a few Mn(II) bands. NIR results of the minerals ardenite, leucophoenicite and alleghanyite are due to hydroxyl and silicate anions which confirming the formulae of the minerals.

  16. Spectroscopic characterization of manganese minerals

    NASA Astrophysics Data System (ADS)

    Lakshmi Reddy, S.; Padma Suvarna, K.; Udayabhaska Reddy, G.; Endo, Tamio; Frost, R. L.

    2014-01-01

    Manganese minerals ardenite, alleghanyite and leucopoenicite originated from Madhya Pradesh, India, Nagano prefecture Japan, Sussex Country and Parker Shaft Franklin, Sussex Country, New Jersey respectively are used in the present work. In these minerals manganese is the major constituent and iron if present is in traces only. An EPR study of on all of the above samples confirms the presence of Mn(II) with g around 2.0. Optical absorption spectrum of the mineral alleghanyite indicates that Mn(II) is present in two different octahedral sites and in leucophoenicite Mn(II) is also in octahedral geometry. Ardenite mineral gives only a few Mn(II) bands. NIR results of the minerals ardenite, leucophoenicite and alleghanyite are due to hydroxyl and silicate anions which confirming the formulae of the minerals.

  17. Microelectrophoresis of selected mineral particles

    NASA Technical Reports Server (NTRS)

    Herren, B. J.; Tipps, R. W.; Alexander, K. D.

    1982-01-01

    Particle mobilities of ilmenite, labradorite plagioclase, enstatite pyroxene, and olivine were measured with a Rank microelectrophoresis system to evaluate indicated mineral separability. Sodium bicarbonate buffer suspension media with and without additives (0.0001 M DTAB and 5 percent v/v ethylene glycol) were used to determine differential adsorption by mineral particles and modification of relative mobilities. Good separability between some minerals was indicated; additives did not enhance separability.

  18. Mineral Time Capsules on Mars?

    NASA Technical Reports Server (NTRS)

    Schirber, Michael

    2006-01-01

    Like dinosaur-age insects trapped in amber, biomolecules sequestered in million-year-old sulfate minerals could provide a glimpse into the past, say researchers who've recently analyzed such minerals from N orth America. The same minerals have recently been discovered on Mars , so they may be a good place to look for traces of past life on the red planet, the researchers say.

  19. [Preventing cardiovascular risk in miners].

    PubMed

    Lipatova, L V; Izmailova, O A

    2016-01-01

    The article presents results concerning usage of intravenous laser radiation of blood in miners with cardiovascular diseases. After cardiovascular state assessment, the miners at high cardiovascular risk were subjected to prophylactic procedures with traditional medical treatment added by intravenous laser therapy. Findings are anti-arrhythmic, antihypertensive, antiatherogenic and anti-aggregation effects of complex treatment with intravenous laser radiation of blood in miners at high cardiovascular risk and its subsequent decrease due to treatment. PMID:27265943

  20. Platinum mineralization in the Kapalagulu Intrusion, western Tanzania

    NASA Astrophysics Data System (ADS)

    Wilhelmij, Harry R.; Cabri, Louis J.

    2016-03-01

    . Impersistent, stratiform PGE mineralized horizons occur within the MCSS harzburgite from which drill core samples were taken for platinum-group mineral (PGM) characterization from two drill holes. Where the PGE reefs reach the surface there is residual PGE mineralization within the laterite regolith from which drill core samples were taken from various laterite lithological units for PGM characterization. As the harzburgite PGE reefs contain significant concentrations of both sulfide and chromite (including chromitite seams) they resemble the PGE-rich chromitite seams of the Bushveld Complex rather than the PGE-bearing Main Sulfide Zone of the Great Dyke and Main Sulfide Layer of the Munni Munni Complex. The dominant Pd PGM in three PGE reef samples varies, ranging ( n = 164, relative wt%) from bismuthides (63 %), bismuthtellurides (19 %), and tellurides (6 %), to tellurides (39 %), bismuthtellurides (24 %), stannides (14 %), and alloys (13 %), and to antimon-arsenides (33 %), stannides (21 %), bismuthides (17 %), tellurides (13 %), and alloys (10 %). From 13.5 % to 21.0 % of the total Pd occurs as a solid solution in pentlandite. The three samples have similar Pt PGM modal distributions ( n = 172, relative wt%); the dominant Pt mineral is sperrylite (79, 58, and 47 %) followed by tellurides (15, 17, 21 %), alloys (2, 1, 1 %), and sulfides (2, 1, 0 %). Comparison of Pd/Pt ratios from assays to those calculated from minerals show that the data for the Pt and Pd PGM are very robust, confirming the concentration methodology and characterization. Study of samples from a shallow drill hole penetrating the laterite regolith shows that the primary Pd mineralization has not survived oxidation, is mainly dispersed, but some was reconstituted to form secondary minerals: cabriite, unnamed tellurides, a selenide, a Pd-Te-Hg mineral, alloys and Pd-bearing secondary sulfides (millerite and heazlewoodite). The primary Pt minerals are more resistant to oxidation and dissolution, especially

  1. Mineralization by nanobacteria

    NASA Astrophysics Data System (ADS)

    Kajander, E. Olavi; Bjorklund, Michael; Ciftcioglu, Neva

    1998-07-01

    Nanobacteria are the smallest cell-walled bacteria, only recently discovered in human and cow blood and in commercial cell culture serum. In this study, we identified with energy-dispersive x-ray microanalysis and chemical analysis that all growth phases of nanobacteria produce biogenic apatite on their cell envelope. Fourier transform IR spectroscopy revealed the mineral as carbonate apatite. Previous models for stone formation have lead to a hypothesis that an elevated pH due to urease and/or alkaline phosphatase activity are important lithogenic factors. Our results indicate that carbonate apatite can be formed without these factors at pH 7.4 at physiological phosphate and calcium concentrations. Due to their specific macromolecules, nanobacteria can produce apatite very efficiency in media mimicking tissue fluids and glomerular filtrate and rapidly mineralizing most of available calcium and phosphate. This can be also monitored by (superscript 85)Sr incorporation and provides a unique model for in vitro studies on calcification. Recently, bacteria have been implicated in the formation of carbonate (hydroxy)fluorapatite in marine sediments. Apatite grains are found so commonly in sedimentary rocks that apatite is omitted in naming the stone. To prove that apatite and other minerals are formed by bacteria would implicate that the bacteria could be observed and their actions followed in stones. We have started to approach this in two ways. Firstly, by the use of sensitive methods for detecting specific bacterial components, like antigens, muramic acid and nucleic acids, that allow for detecting the presence of bacteria and, secondly, by follow-up of volatile bacterial metabolites observed by continuous monitoring with ion mobility spectrometry, IMCELL, working like an artificial, educatable smelling nose. The latter method might allow for remote real time detection of bacterial metabolism, a signature of life, in rocks via fractures of drillholes with or without

  2. Protein- mediated enamel mineralization

    PubMed Central

    Moradian-Oldak, Janet

    2012-01-01

    Enamel is a hard nanocomposite bioceramic with significant resilience that protects the mammalian tooth from external physical and chemical damages. The remarkable mechanical properties of enamel are associated with its hierarchical structural organization and its thorough connection with underlying dentin. This dynamic mineralizing system offers scientists a wealth of information that allows the study of basic principals of organic matrix-mediated biomineralization and can potentially be utilized in the fields of material science and engineering for development and design of biomimetic materials. This chapter will provide a brief overview of enamel hierarchical structure and properties as well as the process and stages of amelogenesis. Particular emphasis is given to current knowledge of extracellular matrix protein and proteinases, and the structural chemistry of the matrix components and their putative functions. The chapter will conclude by discussing the potential of enamel for regrowth. PMID:22652761

  3. Thermodynamic properties of minerals

    USGS Publications Warehouse

    Robie, Richard A.

    1962-01-01

    In the ten years since the publication of the national Bureau of Standards comprehensive tables of thermochemical properties, by Rossini and other (1952), a very large body of modern calorimetric and equilibrium data has become available. Because of the complex interrelations among many thermochemical data and the necessity for internal consistency among these values, a complete revision of this standard reference is required. This is also true of the summaries of thermochemical data for the sulfides (Richardson and Jeffes 1952) and for the oxides (Coughlin 1954). The following tables present critically selected values for the heat and free energy of formation, the logarithm of the equilibrium constant of formation Log Kf, the entropy and the molar volume, at 298.15°K (25.0°C) and one atmosphere for minerals.

  4. Mineral mining installation

    SciTech Connect

    Eggenstein, F.; Plester, K.

    1980-10-14

    A mineral mining installation comprises a longwall structure, such as a conveyor or a winning installation, and a roof support assembly constituted by a plurality of roof support units positioned side-by-side. At least some of the roof support units are provided with hydraulic bracing rams for bracing the longwall structure longitudinally. Each bracing ram is pivotally connected between the longwall structure and the floor sill of a respective roof support unit. Each ram is connected to its floor sill by connection means constituted by a bracket slidably mounted on that floor sill for movement towards, and away from, the longwall structure. Means are provided for securing each of the brackets to its floor sill in any one of a plurality of positions.

  5. Pneumoconiosis of shale miners.

    PubMed Central

    Seaton, A; Lamb, D; Brown, W R; Sclare, G; Middleton, W G

    1981-01-01

    Four patients are described in whom pneumoconiosis was diagnosed towards the end of a lifetime's work in shale mines. All developed complicated pneumoconiosis, diagnosed in two cases at necropsy, in one by lobectomy, and in one radiologically. Two of the patients were found at necropsy also to have peripheral squamous lung cancer.The clinical and histological features of the disease resembled the pneumoconioses of coalminers and kaolin workers and the lungs of three of the patients were shown to contain dust composed predominantly of kaolinite, mica, and silica. Shale miners' complicated pneumoconiosis has not previously been described. Although the British shale industry is now defunct, oil production from shale is expanding in other countries, notably the USA. It is suggested that control should be exercised over dust exposure levels in this industry and that epidemiological studies should be carried out to quantify the risks of both pneumoconiosis and bronchial carcinoma. Images PMID:7314011

  6. Marine Mineral Exploration

    NASA Astrophysics Data System (ADS)

    Spiess, Fren N.

    This book is the forty-first in the Elsevier Oceanography Series, and with it the series has come full circle. Its first title, published in 1964, was John Mero's landmark study The Mineral Resources of the Sea [Mero, 1964]. Looking back at that first major treatise and comparing it with this and other recent books on the topic [e.g., Teleki et al., 1987] one cannot help but be impressed with how well Mero used the sparse data and studies that had been put together by his time. Twenty-two years and many millions of dollars later a substantial mining-oriented base of knowledge has been built — we know much more about the economics and the engineering — yet the basic premises and conclusions that Mero assembled are still intact, and answers to the fundamental questions (e.g., formation processes for manganese nodules) are not in much better condition than they were then.

  7. Minerals Bill introduced in House

    NASA Astrophysics Data System (ADS)

    Richman, Barbara T.

    A bill that aims to strengthen a national minerals policy and to establish a three-member White-House-level council to coordinate the development of this policy was introduced in the House of Representatives on April 30 by James D. Santini (D-Nev.). Entitled the National Minerals Security Act (NMSA), the legislation, if passed, also would amend tax laws to assist the mining industry to make capital investments to locate and produce strategic minerals; it would provide the means for the Secretary of the Interior to make withdrawn public lands available for mineral development; and it would create a revolving fund for the sale and purchase of strategic minerals.Santini estimates that 4 billion tons of minerals are needed annually to sustain the nation's economy. Much of the minerals are supplied by other nations, however; Santini wants to see an end to the United States' dependence on foreign countries, especially those that seem relatively unstable politically. ‘The U.S. has placed its national security in the hands of a few foreign nations,’ Santini said in a recent press conference. ‘We are heavily dependent on the region of southern Africa for 76% of our cobalt, 93% of our platinum, 48% of our chromium, and a host of other strategic and critical minerals. Without these minerals, we cannot build jet aircraft, weapons, or other military hardware vitally important to our national security.’

  8. Bone and Mineral Metabolism in Patients with Primary Aldosteronism

    PubMed Central

    Petramala, Luigi; Zinnamosca, Laura; Settevendemmie, Amina; Marinelli, Cristiano; Nardi, Matteo; Concistrè, Antonio; Corpaci, Francesco; Tonnarini, Gianfranco; De Toma, Giorgio; Letizia, Claudio

    2014-01-01

    Primary aldosteronism represents major cause of secondary hypertension, strongly associated with high cardiovascular morbidity and mortality. Aldosterone excess may influence mineral homeostasis, through higher urinary calcium excretion inducing secondary increase of parathyroid hormone. Recently, in a cohort of PA patients a significant increase of primary hyperparathyroidism was found, suggesting a bidirectional functional link between the adrenal and parathyroid glands. The aim of this study was to evaluate the impact of aldosterone excess on mineral metabolism and bone mass density. In 73 PA patients we evaluated anthropometric and biochemical parameters, renin-angiotensin-aldosterone system, calcium-phosphorus metabolism, and bone mineral density; control groups were 73 essential hypertension (EH) subjects and 40 healthy subjects. Compared to HS and EH, PA subjects had significantly lower serum calcium levels and higher urinary calcium excretion. Moreover, PA patients showed higher plasma PTH, lower serum 25(OH)-vitamin D levels, higher prevalence of vitamin D deficiency (65% versus 25% and 25%; P < 0.001), and higher prevalence of osteopenia/osteoporosis (38.5 and 10.5%) than EH (28% and 4%) and NS (25% and 5%), respectively. This study supports the hypothesis that bone loss and fracture risk in PA patients are potentially the result of aldosterone mediated hypercalciuria and the consecutive secondary hyperparathyroidism. PMID:24864141

  9. [Secondary chondrosarcoma: radiopathological correlation].

    PubMed

    Lozano Martínez, G A; Llauger Rosselló, J

    2015-01-01

    Chondrosarcomas are malignant bone tumors originating in cartilage. Chondrosarcoma is the third most common malignant bone tumor after multiple myeloma and osteosarcoma. About 75% of chondrosarcomas are primary lesions. The remaining 25% belong to special categories such as histologic variants and secondary forms. A secondary chondrosarcoma is one that appears in a pre-existing benign chondral lesion; the different types of secondary chondrosarcomas include solitary osteochondroma, multiple osteochondromatosis, enchondroma, the different types of enchondromatosis, and primary synovial chondromatosis. The incidence of this malignant transformation varies widely in function of the type of lesion. In this article, we discuss and illustrate the different types of secondary chondrosarcomas, placing special emphasis on the imaging findings that should alert to these lesions and give radiologists a key role in the diagnosis, management, and follow-up of these patients.

  10. Nitrogen Mineralization and Assimilation at Millimeter Scales

    SciTech Connect

    Cliff, John B.; Bottomley, Peter J.; Gaspar, Dan J.; Myrold, David D.

    2006-11-15

    This study used inoculated, artificial soil microcosms containing sand, clay, cellulose, and localized hotspots of highly labile, organic-N containing dead bacteria to study N mineralization and assimilation at submillimeter and centimeter scales. Labeling with 15NH4+ along with measurement of label assimilated into microbial biomass at the bulk scale allowed estimation of gross rates of ammonification and N assimilation using isotope dilution. Time-of-flight secondary ion mass spectrometry (ToF-SIMS) analyses of transects of organic-15N across Si wafers in contact with the microcosms indicated strong gradients of 15NH4+ assimilation as a function of proximity to the hotspots that were not apparent using bulk analyses. This combination of bulk and ToF-SIMS analyses represents a powerful approach to explore the physical and biochemical factors that affect N process heterogeneities in soils.

  11. Mineral Detector for Igneous Rocks

    NASA Astrophysics Data System (ADS)

    Ishikawa, S. T.; Hart, S. D.; Gulick, V. C.

    2010-12-01

    We present a Raman spectral analysis tool that uses machine learning algorithms to classify pure minerals in igneous rocks. Experiments show greater than 90% accuracy classifying a test set of pure minerals against a database of similar reference minerals using an artificial neural network. Efforts are currently underway to improve this tool for use as a mineral detector in rock samples, an important milestone toward autonomously classifying rocks based on spectral, and previous imaging work. Although pure mineral classification has been widely successful, applying the same methods to rocks is difficult because the spectra may represent a combination of multiple, and often competing, mineral signatures. In such cases some minerals may appear with more intensity than others resulting in masking of weaker minerals. Furthermore, with our particular spectrometer (852 nm excitation, ~50 micron spot size), minerals such as potassium feldspar fluoresce, both obscuring its characteristic Raman features and suppressing those of weaker minerals. For example, plagioclase and quartz, two key minerals for determining the composition of igneous rocks, are often hidden by minerals such as potassium feldspar and pyroxene, and are consequently underrepresented in the spectral analysis. These technicalities tend to skew the perceived composition of a rock from its actual composition. Despite these obstacles, an experiment involving a training set of 26 minerals (plagioclase, potassium feldspar, pyroxene, olivine, quartz) and a test set of 57 igneous rocks (basalt, gabbro, andesite, diorite, dacite, granodiorite, rhyolite, granite) shows that generalizations derived from their spectral data are consistent with expected trends: as rock composition goes from felsic to mafic there is a marked increase in the detection of minerals such as plagioclase and pyroxene along with a decrease in the detection of minerals such as quartz and potassium feldspar. The results suggest that phaneritic

  12. Quantification of Secondary Metabolites.

    PubMed

    2016-01-01

    Plants are a rich source of secondary metabolites that have medicinal and aromatic properties. Secondary metabolites such as alkaloids, iridoids and phenolics generally produced by plants for their defence mechanisms have been implicated in the therapeutic properties of most medicinal plants. Hence, quantification of these metabolites will aid to discover new and effective drugs from plant sources and also to scientifically validate the existing traditional practices. Quantification of large group of phytochemicals such as phenolics and flavonoids is quantified in this context.

  13. Estimating secondary color.

    PubMed

    Walker, B H

    1993-12-01

    Image quality of a refracting lens system often will be limited by residual secondary color. Information in this paper permits rapid determination of blur spot size, and resulting image quality degradation, due to secondary color for a refracting lens system that has been designed with normal optical glasses and is free of primary color (achromatic). Included here is a brief description of the basic theory involved and an example of how the plotted data are used. PMID:20856581

  14. Secondary pool boiling effects

    NASA Astrophysics Data System (ADS)

    Kruse, C.; Tsubaki, A.; Zuhlke, C.; Anderson, T.; Alexander, D.; Gogos, G.; Ndao, S.

    2016-02-01

    A pool boiling phenomenon referred to as secondary boiling effects is discussed. Based on the experimental trends, a mechanism is proposed that identifies the parameters that lead to this phenomenon. Secondary boiling effects refer to a distinct decrease in the wall superheat temperature near the critical heat flux due to a significant increase in the heat transfer coefficient. Recent pool boiling heat transfer experiments using femtosecond laser processed Inconel, stainless steel, and copper multiscale surfaces consistently displayed secondary boiling effects, which were found to be a result of both temperature drop along the microstructures and nucleation characteristic length scales. The temperature drop is a function of microstructure height and thermal conductivity. An increased microstructure height and a decreased thermal conductivity result in a significant temperature drop along the microstructures. This temperature drop becomes more pronounced at higher heat fluxes and along with the right nucleation characteristic length scales results in a change of the boiling dynamics. Nucleation spreads from the bottom of the microstructure valleys to the top of the microstructures, resulting in a decreased surface superheat with an increasing heat flux. This decrease in the wall superheat at higher heat fluxes is reflected by a "hook back" of the traditional boiling curve and is thus referred to as secondary boiling effects. In addition, a boiling hysteresis during increasing and decreasing heat flux develops due to the secondary boiling effects. This hysteresis further validates the existence of secondary boiling effects.

  15. Sustainable mineral resources management: from regional mineral resources exploration to spatial contamination risk assessment of mining

    NASA Astrophysics Data System (ADS)

    Jordan, Gyozo

    2009-07-01

    Wide-spread environmental contamination associated with historic mining in Europe has triggered social responses to improve related environmental legislation, the environmental assessment and management methods for the mining industry. Mining has some unique features such as natural background contamination associated with mineral deposits, industrial activities and contamination in the three-dimensional subsurface space, problem of long-term remediation after mine closure, problem of secondary contaminated areas around mine sites, land use conflicts and abandoned mines. These problems require special tools to address the complexity of the environmental problems of mining-related contamination. The objective of this paper is to show how regional mineral resources mapping has developed into the spatial contamination risk assessment of mining and how geological knowledge can be transferred to environmental assessment of mines. The paper provides a state-of-the-art review of the spatial mine inventory, hazard, impact and risk assessment and ranking methods developed by national and international efforts in Europe. It is concluded that geological knowledge on mineral resources exploration is essential and should be used for the environmental contamination assessment of mines. Also, sufficient methodological experience, knowledge and documented results are available, but harmonisation of these methods is still required for the efficient spatial environmental assessment of mine contamination.

  16. Nitrogen mineralization in production agriculture

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Understanding the effects of N management and how it relates to the N cycle in soil ecosystems is essential to determining N availability. This manuscript describes the importance of N mineralization to production agriculture and introduces a special issue on “N Mineralization in Production Agricult...

  17. Ways to defuse miners' anger

    SciTech Connect

    Not Available

    1984-06-01

    The violence and riots which often occur with mining personnel are considered. The emotions and feelings which miners often experience because of their work environment are dealth with. From recognizing the pressures, the article then works to present methods to help defuse the miners' hostility and anger.

  18. Plant macro- and micronutrient minerals

    Technology Transfer Automated Retrieval System (TEKTRAN)

    All plants must obtain a number of inorganic mineral elements from their environment to ensure successful growth and development of both vegetative and reproductive tissues. A total of fourteen mineral nutrients are considered to be essential. Several other elements have been shown to have beneficia...

  19. A Mineral Processing Field Course

    ERIC Educational Resources Information Center

    Carmody, Maurice

    2014-01-01

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

  20. From Mountain Men to Miners.

    ERIC Educational Resources Information Center

    Stevens, Robert L.; Fogel, Jared A.

    1999-01-01

    Examines three of the changes wrought by coal mining: (1) the miner's working conditions; (2) the establishment of company towns; and (3) the violence that ensued when miners from Harlan County, Kentucky, referred to as "Bloody Harlan," tried to better their lives by joining labor unions. (CMK)

  1. Mineral Resources and the Environment.

    ERIC Educational Resources Information Center

    National Academy of Sciences, Washington, DC.

    This report presents the findings and recommendations of panels created by the Committee on Mineral Resources and the Environment (COMRATE) to study four topic areas of mineral resources and the environment. The topic areas studied by the panels were: technology, supply, the environment, and demand. Section I, the report of the technology panel,…

  2. 76 FR 6110 - Conflict Minerals

    Federal Register 2010, 2011, 2012, 2013, 2014

    2011-02-03

    ... FR 80948 (December 23, 2010)]. The original comment period for Release No. 34-63547 is scheduled to... COMMISSION 17 CFR Parts 229 and 249 RIN 3235-AK84 Conflict Minerals AGENCY: Securities and Exchange... 1934 (the ``Exchange Act'') and would require any such issuer for which conflict minerals are...

  3. Investigating Minerals: Promoting Integrated Inquiry

    ERIC Educational Resources Information Center

    Thompson, Rudi; Carmack, Elizabeth

    2007-01-01

    "Mineral Detectives!" is one of eighteen lessons in the "Private Whys?" integrated science unit, which uses a guided inquiry investigation to teach students in grades three through five about the role of minerals in our lives. The University of North Texas developed "Private Whys?" with funding from the Copper Development Association. This lesson…

  4. Adsorption of reovirus by minerals and soils.

    PubMed Central

    Moore, R S; Taylor, D H; Reddy, M M; Sturman, L S

    1982-01-01

    Adsorption of [35S]methionine-labeled reovirus by 30 dry soils, minerals, and finely ground rocks suspended in synthetic freshwater at pH 7 was investigated to determine the conditions necessary for optimum virus removal during land application of wastewaters. All of the minerals and soils studied were excellent adsorbents of reovirus, with greater than 99% of the virus adsorbed after 1 h at 4 degrees C. Thereafter, virus remaining in suspension was significantly inactivated, and within 24 h a three to five log10 reduction in titer occurred. The presence of divalent cations, i.e., Ca2+ and Mg2+, in synthetic freshwater enhanced removal, whereas soluble organic matter decreased the amount of virus adsorbed in secondary effluent. The amount of virus adsorbed by these substrates was inversely correlated with the amount of organic matter, capacity to adsorb cationic polyelectrolyte, and electrophoretic mobility. Adsorption increased with increasing available surface area, as suspended infectivity was reduced further by the more finely divided substrates. However, the organic content of the soils reduced the level of infectious virus adsorbed below that expected from surface area measurements alone. The inverse correlation between virus adsorption and substrate capacity for cationic polyelectrolyte indicates that the adsorption of infectious reovirus particles is predominately a charged colloidal particle-charged surface interaction. Thus, adsorption of polyelectrolyte may be useful in predicting the fate of viruses during land application of sewage effluents and sludges. PMID:7149717

  5. Renal Clearance of Mineral Metabolism Biomarkers.

    PubMed

    van Ballegooijen, Adriana J; Rhee, Eugene P; Elmariah, Sammy; de Boer, Ian H; Kestenbaum, Bryan

    2016-02-01

    CKD leads to disturbances in multiple interrelated hormones that regulate bone and mineral metabolism. The renal handling of mineral metabolism hormones in humans is incompletely understood. We determined the single-pass renal clearance of parathyroid hormone, fibroblast growth factor 23, vitamin D metabolites, and phosphate from paired blood samples collected from the abdominal aorta and renal vein in 17 participants undergoing simultaneous right and left heart catheterization and estimated associations of eGFR with the renal elimination of metabolites. The mean age ±SD of the study population was 71.4±10.0 years and 11 participants (65%) were male. We found a relatively large mean±SD single-pass renal extraction of parathyroid hormone (44.2%±10.3%) that exceeded the extraction of creatinine (22.1%±7.9%). The proportionate renal extraction of parathyroid hormone correlated with eGFR. The renal extraction of fibroblast growth factor 23 was, on average, lower than that of parathyroid hormone with greater variability across individuals (17.1%±19.5%). There were no differences in the mean concentrations of vitamin D metabolites across the renal vein and artery. In summary, we demonstrate substantial single-pass renal extraction of parathyroid hormone at a rate that exceeds glomerular filtration. Impaired renal clearance of parathyroid hormone may contribute to secondary hyperparathyroidism in CKD.

  6. Ex situ aqueous mineral carbonation.

    PubMed

    Gerdemann, Stephen J; O'Connor, William K; Dahlin, David C; Penner, Larry R; Rush, Hank

    2007-04-01

    The U.S. Department of Energy's National Energy Technology Laboratory (NETL) located in Albany, OR (formerly the Albany Research Center) has studied ex situ mineral carbonation as a potential option for carbon dioxide sequestration. Studies focused on the reaction of Ca-, Fe-, and Mg-silicate minerals with gaseous CO2 to form geologically stable, naturally occurring solid carbonate minerals. The research included resource evaluation, kinetic studies, process development, and economic evaluation. An initial cost estimate of approximately $69/ton of CO2 sequestered was improved with process improvements to $54/ton. The scale of ex situ mineral carbonation operations, requiring 55 000 tons of mineral to carbonate, the daily CO2 emissions from a 1-GW, coal-fired power plant, may make such operations impractical.

  7. Ex Situ Aqueous Mineral Carbonation

    SciTech Connect

    Gerdemann, S.J.; O'Connor, W.K.; Dahlin, D.C.; Penner, L.R.; Rush, G.E.

    2007-04-01

    The U.S. Department of Energy's National Energy Technology Laboratory (NETL) located in Albany, OR (formerly the Albany Research Center) has studied ex situ mineral carbonation as a potential option for carbon dioxide sequestration. Studies focused on the reaction of Ca-, Fe-, and Mg-silicate minerals with gaseous CO2 to form geologically stable, naturally occurring solid carbonate minerals. The research included resource evaluation, kinetic studies, process development, and economic evaluation. An initial cost estimate of ~$69/ton of CO2 sequestered was improved with process improvements to ~$54/ton. The scale of ex situ mineral carbonation operations, requiring ~55 000 tons of mineral to carbonate, the daily CO2 emissions from a 1-GW, coal-fired power plant, may make such operations impractical.

  8. Ex situ aqueous mineral carbonation

    SciTech Connect

    Stephen J. Gerdemann; William K. O'Connor; David C. Dahlin; Larry R. Penner; Hank Rush

    2007-04-01

    The U.S. Department of Energy's National Energy Technology Laboratory (NETL) located in Albany, OR (formerly the Albany Research Center) has studied ex situ mineral carbonation as a potential option for carbon dioxide sequestration. Studies focused on the reaction of Ca-, Fe-, and Mg-silicate minerals with gaseous CO{sub 2} to form geologically stable, naturally occurring solid carbonate minerals. The research included resource evaluation, kinetic studies, process development, and economic evaluation. An initial cost estimate of about $69/ton of CO{sub 2} sequestered was improved with process improvements to about 54/ton. The scale of ex situ mineral carbonation operations, requiring about 55,000 tons of mineral to carbonate, the daily CO{sub 2} emissions from a 1-GW, coal-fired power plant, may make such operations impractical. 23 refs., 4 figs., 5 tabs.

  9. 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..

  10. Universal ripper miner

    DOEpatents

    Morrell, Roger J.; Larson, David A.

    1991-01-01

    A universal ripper miner used to cut, collect and transfer material from an underground mine working face includes a cutter head that is vertically movable in an arcuate cutting cycle by means of drive members, such as hydraulically actuated pistons. The cutter head may support a circular cutter bit having a circular cutting edge that may be indexed to incrementally expose a fresh cutting edge. An automatic indexing system is disclosed wherein indexing occurs by means of a worm gear and indexing lever mechanism. The invention also contemplates a bi-directional bit holder enabling cutting to occur in both the upstroke and the downstroke cutting cycle. Another feature of the invention discloses multiple bits arranged in an in-line, radially staggered pattern, or a side-by-side pattern to increase the mining capacity in each cutting cycle. An on-board resharpening system is also disclosed for resharpening the cutting edge at the end of cutting stroke position. The aforementioned improvement features may be used either singly, or in any proposed combination with each other.

  11. Mineral evolution of bone.

    PubMed

    Ravaglioli, A; Krajewski, A; Celotti, G C; Piancastelli, A; Bacchini, B; Montanari, L; Zama, G; Piombi, L

    1996-03-01

    A study on the evolution with age of the mineral composition of bones was performed on samples belonging to human and other common mammalian species (cattle, sheep, dog). The study was carried out on the ashes obtained by calcination of the bone samples (1 h at 900 degrees C). The calcined powders were carefully examined by X-ray diffraction, from which precise quantitative evaluation (also confirmed by chemical analysis) of the crystalline phases present was derived. These data were analysed as a function of the introduced fractional age phi, a new relative scale that allows even largely different lifespan species to be compared. An overall linear increase in (Ca + Mg)/P ratio with log phi was found and the other considerations on molecular constitution (especially as regards Mg2+ substituting for Ca2+ in very young subjects) of the various phases detected were formulated and relative implications evaluated. The results appear promising for an improvement of knowledge in the field of biomedical experimentation and clinical implantology.

  12. Carbonate-mineral/water interactions in sulfide-rich mine tailings

    NASA Astrophysics Data System (ADS)

    Al, Tom A.; Martin, Chris J.; Blowes, David W.

    2000-12-01

    The chemical composition and mineralogy of coatings on carbonate minerals from mine tailings have been studied using aqueous geochemical methods, Time-of-Flight Laser-Ionization Mass Spectrometry (TOF-LIMS) and Transmission Electron Microscopy (TEM). The goal is to study major and trace element partitioning between the aqueous and solid phase, and to infer mechanisms that control the concentrations of elements in the pore water of sulfide-rich mine tailings. Pore-water samples and carbonate-mineral grains were collected from four geochemically distinct zones within the tailings. Oxidation of sulfide minerals near the surface results in a large range in pore-water pH (3.85 to 6.98) and aqueous concentrations of metals and sulfate. With increasing depth in the tailings, mineral-water interactions lead to increasing pH, and decreasing concentrations of metals and sulfate. Calculated mineral saturation indices, trends in the abundance of Ca, Fe, Mg and Mn in TOF-LIMS profiles through the secondary coatings, and electron diffraction patterns obtained from the coatings, suggest that precipitation/dissolution of jarosite-group minerals, gypsum, goethite, akaganéite, amorphous Fe oxyhydroxides and siderite control the aqueous Ca, Fe, Na, K and SO 4 concentrations. The occurrence of secondary coatings on primary minerals is widespread, and reactions with the secondary minerals, rather than the primary mineral substrate, probably represent the principal controls on trace-element distributions in the pore water. The data indicate that adsorption, surface-complexation and co-precipitation reactions are important controls on the concentrations of trace elements in the pore water. The occurrence of siderite coatings on the surface of ankerite grains suggests that Fe-bearing dolomite-structure carbonate minerals dissolve incongruently. This corroborates inferences made by previous workers that solubility differences between calcite and siderite lead to calcite dissolution and

  13. 30 CFR 57.5070 - Miner training.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... 30 Mineral Resources 1 2010-07-01 2010-07-01 false Miner training. 57.5070 Section 57.5070 Mineral... Agents, and Diesel Particulate Matter Diesel Particulate Matter-Underground Only § 57.5070 Miner training. (a) Mine operators must provide annual training to all miners at a mine covered by this part who...

  14. 43 CFR 3816.1 - Mineral locations.

    Code of Federal Regulations, 2014 CFR

    2014-10-01

    ... 43 Public Lands: Interior 2 2014-10-01 2014-10-01 false Mineral locations. 3816.1 Section 3816.1..., DEPARTMENT OF THE INTERIOR MINERALS MANAGEMENT (3000) LANDS AND MINERALS SUBJECT TO LOCATION Mineral Locations in Reclamation Withdrawals § 3816.1 Mineral locations. The Act of April 23, 1932 (47 Stat. 136;...

  15. 43 CFR 3815.1 - Mineral locations.

    Code of Federal Regulations, 2012 CFR

    2012-10-01

    ... 43 Public Lands: Interior 2 2012-10-01 2012-10-01 false Mineral locations. 3815.1 Section 3815.1..., DEPARTMENT OF THE INTERIOR MINERALS MANAGEMENT (3000) LANDS AND MINERALS SUBJECT TO LOCATION Mineral Locations in Stock Driveway Withdrawals § 3815.1 Mineral locations. Under authority of the provisions of...

  16. 43 CFR 3816.1 - Mineral locations.

    Code of Federal Regulations, 2012 CFR

    2012-10-01

    ... 43 Public Lands: Interior 2 2012-10-01 2012-10-01 false Mineral locations. 3816.1 Section 3816.1..., DEPARTMENT OF THE INTERIOR MINERALS MANAGEMENT (3000) LANDS AND MINERALS SUBJECT TO LOCATION Mineral Locations in Reclamation Withdrawals § 3816.1 Mineral locations. The Act of April 23, 1932 (47 Stat. 136;...

  17. 43 CFR 3815.1 - Mineral locations.

    Code of Federal Regulations, 2013 CFR

    2013-10-01

    ... 43 Public Lands: Interior 2 2013-10-01 2013-10-01 false Mineral locations. 3815.1 Section 3815.1..., DEPARTMENT OF THE INTERIOR MINERALS MANAGEMENT (3000) LANDS AND MINERALS SUBJECT TO LOCATION Mineral Locations in Stock Driveway Withdrawals § 3815.1 Mineral locations. Under authority of the provisions of...

  18. 43 CFR 3815.1 - Mineral locations.

    Code of Federal Regulations, 2011 CFR

    2011-10-01

    ... 43 Public Lands: Interior 2 2011-10-01 2011-10-01 false Mineral locations. 3815.1 Section 3815.1..., DEPARTMENT OF THE INTERIOR MINERALS MANAGEMENT (3000) LANDS AND MINERALS SUBJECT TO LOCATION Mineral Locations in Stock Driveway Withdrawals § 3815.1 Mineral locations. Under authority of the provisions of...

  19. 43 CFR 3816.1 - Mineral locations.

    Code of Federal Regulations, 2011 CFR

    2011-10-01

    ... 43 Public Lands: Interior 2 2011-10-01 2011-10-01 false Mineral locations. 3816.1 Section 3816.1..., DEPARTMENT OF THE INTERIOR MINERALS MANAGEMENT (3000) LANDS AND MINERALS SUBJECT TO LOCATION Mineral Locations in Reclamation Withdrawals § 3816.1 Mineral locations. The Act of April 23, 1932 (47 Stat. 136;...

  20. 43 CFR 3815.1 - Mineral locations.

    Code of Federal Regulations, 2014 CFR

    2014-10-01

    ... 43 Public Lands: Interior 2 2014-10-01 2014-10-01 false Mineral locations. 3815.1 Section 3815.1..., DEPARTMENT OF THE INTERIOR MINERALS MANAGEMENT (3000) LANDS AND MINERALS SUBJECT TO LOCATION Mineral Locations in Stock Driveway Withdrawals § 3815.1 Mineral locations. Under authority of the provisions of...

  1. 43 CFR 3816.1 - Mineral locations.

    Code of Federal Regulations, 2013 CFR

    2013-10-01

    ... 43 Public Lands: Interior 2 2013-10-01 2013-10-01 false Mineral locations. 3816.1 Section 3816.1..., DEPARTMENT OF THE INTERIOR MINERALS MANAGEMENT (3000) LANDS AND MINERALS SUBJECT TO LOCATION Mineral Locations in Reclamation Withdrawals § 3816.1 Mineral locations. The Act of April 23, 1932 (47 Stat. 136;...

  2. Microtextured Surfaces for Turbine Blade Impingement Cooling

    NASA Technical Reports Server (NTRS)

    Fryer, Jack

    2014-01-01

    Gas turbine engine technology is constantly challenged to operate at higher combustor outlet temperatures. In a modern gas turbine engine, these temperatures can exceed the blade and disk material limits by 600 F or more, necessitating both internal and film cooling schemes in addition to the use of thermal barrier coatings. Internal convective cooling is inadequate in many blade locations, and both internal and film cooling approaches can lead to significant performance penalties in the engine. Micro Cooling Concepts, Inc., has developed a turbine blade cooling concept that provides enhanced internal impingement cooling effectiveness via the use of microstructured impingement surfaces. These surfaces significantly increase the cooling capability of the impinging flow, as compared to a conventional untextured surface. This approach can be combined with microchannel cooling and external film cooling to tailor the cooling capability per the external heating profile. The cooling system then can be optimized to minimize impact on engine performance.

  3. Microtextural characterization of annealed and deformed copper

    SciTech Connect

    Wright, S.I.; Heidelbach, F.

    1993-09-01

    Even though deformation produces material with preferred orientation it appears to randomize the grain boundary texture in copper. It appears that as dislocations move through the material the resulting lattice rotations serve to break down the twin structure in a stochastic manner. An effort was made to use the automatic BEKP data to search for dislocation cell wall structures. However, no evidence was found for such structure. This may be due, in part, to the resolution of the backscatter electron Kikuchidi diffraction patter technique. Diffraction occurs from an area with mean diameter of approximately 0.5 {mu}m.

  4. Bisphophonates in CKD Patients with Low Bone Mineral Density

    PubMed Central

    Liu, Wen-Chih; Yen, Jen-Fen; Lu, Kuo-Cheng

    2013-01-01

    Patients with chronic kidney disease-mineral and bone disorder (CKD-MBD) have a high risk of bone fracture because of low bone mineral density and poor bone quality. Osteoporosis also features low bone mass, disarranged microarchitecture, and skeletal fragility, and differentiating between osteoporosis and CKD-MBD in low bone mineral density is a challenge and usually achieved by bone biopsy. Bisphosphonates can be safe and beneficial for patients with a glomerular filtration rate of 30 mL/min or higher, but prescribing bisphosphonates in advanced CKD requires caution because of the increased possibility of low bone turnover disorders such as osteomalacia, mixed uremic osteodystrophy, and adynamic bone, even aggravating hyperparathyroidism. Therefore, bone biopsy in advanced CKD is an important consideration before prescribing bisphosphonates. Treatment also may induce hypocalcemia in CKD patients with secondary hyperparathyroidism, but vitamin D supplementation may ameliorate this effect. Bisphosphonate treatment can improve both bone mineral density and vascular calcification, but the latter becomes more unlikely in patients with stage 3-4 CKD with vascular calcification but no decreased bone mineral density. Using bisphosphonates requires considerable caution in advanced CKD, and the lack of adequate clinical investigation necessitates more studies regarding its effects on these patients. PMID:24501586

  5. Diagenesis and clay mineral formation at Gale Crater, Mars

    NASA Astrophysics Data System (ADS)

    Bridges, J. C.; Schwenzer, S. P.; Leveille, R.; Westall, F.; Wiens, R. C.; Mangold, N.; Bristow, T.; Edwards, P.; Berger, G.

    2015-01-01

    Mars Science Laboratory rover Curiosity found host rocks of basaltic composition and alteration assemblages containing clay minerals at Yellowknife Bay, Gale Crater. On the basis of the observed host rock and alteration minerals, we present results of equilibrium thermochemical modeling of the Sheepbed mudstones of Yellowknife Bay in order to constrain the formation conditions of its secondary mineral assemblage. Building on conclusions from sedimentary observations by the Mars Science Laboratory team, we assume diagenetic, in situ alteration. The modeling shows that the mineral assemblage formed by the reaction of a CO2-poor and oxidizing, dilute aqueous solution (Gale Portage Water) in an open system with the Fe-rich basaltic-composition sedimentary rocks at 10-50°C and water/rock ratio (mass of rock reacted with the starting fluid) of 100-1000, pH of ~7.5-12. Model alteration assemblages predominantly contain phyllosilicates (Fe-smectite, chlorite), the bulk composition of a mixture of which is close to that of saponite inferred from Chemistry and Mineralogy data and to that of saponite observed in the nakhlite Martian meteorites and terrestrial analogues. To match the observed clay mineral chemistry, inhomogeneous dissolution dominated by the amorphous phase and olivine is required. We therefore deduce a dissolving composition of approximately 70% amorphous material, with 20% olivine, and 10% whole rock component.

  6. Bisphophonates in CKD patients with low bone mineral density.

    PubMed

    Liu, Wen-Chih; Yen, Jen-Fen; Lang, Cheng-Lin; Yan, Ming-Tso; Lu, Kuo-Cheng

    2013-01-01

    Patients with chronic kidney disease-mineral and bone disorder (CKD-MBD) have a high risk of bone fracture because of low bone mineral density and poor bone quality. Osteoporosis also features low bone mass, disarranged microarchitecture, and skeletal fragility, and differentiating between osteoporosis and CKD-MBD in low bone mineral density is a challenge and usually achieved by bone biopsy. Bisphosphonates can be safe and beneficial for patients with a glomerular filtration rate of 30 mL/min or higher, but prescribing bisphosphonates in advanced CKD requires caution because of the increased possibility of low bone turnover disorders such as osteomalacia, mixed uremic osteodystrophy, and adynamic bone, even aggravating hyperparathyroidism. Therefore, bone biopsy in advanced CKD is an important consideration before prescribing bisphosphonates. Treatment also may induce hypocalcemia in CKD patients with secondary hyperparathyroidism, but vitamin D supplementation may ameliorate this effect. Bisphosphonate treatment can improve both bone mineral density and vascular calcification, but the latter becomes more unlikely in patients with stage 3-4 CKD with vascular calcification but no decreased bone mineral density. Using bisphosphonates requires considerable caution in advanced CKD, and the lack of adequate clinical investigation necessitates more studies regarding its effects on these patients. PMID:24501586

  7. Diagenesis and clay mineral formation at Gale Crater, Mars

    PubMed Central

    Bridges, J C; Schwenzer, S P; Leveille, R; Westall, F; Wiens, R C; Mangold, N; Bristow, T; Edwards, P; Berger, G

    2015-01-01

    The Mars Science Laboratory rover Curiosity found host rocks of basaltic composition and alteration assemblages containing clay minerals at Yellowknife Bay, Gale Crater. On the basis of the observed host rock and alteration minerals, we present results of equilibrium thermochemical modeling of the Sheepbed mudstones of Yellowknife Bay in order to constrain the formation conditions of its secondary mineral assemblage. Building on conclusions from sedimentary observations by the Mars Science Laboratory team, we assume diagenetic, in situ alteration. The modeling shows that the mineral assemblage formed by the reaction of a CO2-poor and oxidizing, dilute aqueous solution (Gale Portage Water) in an open system with the Fe-rich basaltic-composition sedimentary rocks at 10–50°C and water/rock ratio (mass of rock reacted with the starting fluid) of 100–1000, pH of ∽7.5–12. Model alteration assemblages predominantly contain phyllosilicates (Fe-smectite, chlorite), the bulk composition of a mixture of which is close to that of saponite inferred from Chemistry and Mineralogy data and to that of saponite observed in the nakhlite Martian meteorites and terrestrial analogues. To match the observed clay mineral chemistry, inhomogeneous dissolution dominated by the amorphous phase and olivine is required. We therefore deduce a dissolving composition of approximately 70% amorphous material, with 20% olivine, and 10% whole rock component. PMID:26213668

  8. Diagenesis and clay mineral formation at Gale Crater, Mars

    DOE PAGES

    Bridges, J. C.; Schwenzer, S. P.; Leveille, R.; Westall, F.; Wiens, R. C.; Mangold, N.; Bristow, T.; Edwards, P.; Berger, G.

    2015-01-18

    The Mars Science Laboratory rover Curiosity found host rocks of basaltic composition and alteration assemblages containing clay minerals at Yellowknife Bay, Gale Crater. On the basis of the observed host rock and alteration minerals, we present results of equilibrium thermochemical modeling of the Sheepbed mudstones of Yellowknife Bay in order to constrain the formation conditions of its secondary mineral assemblage. Building on conclusions from sedimentary observations by the Mars Science Laboratory team, we assume diagenetic, in situ alteration. The modeling shows that the mineral assemblage formed by the reaction of a CO₂-poor and oxidizing, dilute aqueous solution (Gale Portage Water)more » in an open system with the Fe-rich basaltic-composition sedimentary rocks at 10–50°C and water/rock ratio (mass of rock reacted with the starting fluid) of 100–1000, pH of ~7.5–12. Model alteration assemblages predominantly contain phyllosilicates (Fe-smectite, chlorite), the bulk composition of a mixture of which is close to that of saponite inferred from Chemistry and Mineralogy data and to that of saponite observed in the nakhlite Martian meteorites and terrestrial analogues. To match the observed clay mineral chemistry, inhomogeneous dissolution dominated by the amorphous phase and olivine is required. We therefore deduce a dissolving composition of approximately 70% amorphous material, with 20% olivine, and 10% whole rock component.« less

  9. Diagenesis and clay mineral formation at Gale Crater, Mars

    SciTech Connect

    Bridges, J. C.; Schwenzer, S. P.; Leveille, R.; Westall, F.; Wiens, R. C.; Mangold, N.; Bristow, T.; Edwards, P.; Berger, G.

    2015-01-18

    The Mars Science Laboratory rover Curiosity found host rocks of basaltic composition and alteration assemblages containing clay minerals at Yellowknife Bay, Gale Crater. On the basis of the observed host rock and alteration minerals, we present results of equilibrium thermochemical modeling of the Sheepbed mudstones of Yellowknife Bay in order to constrain the formation conditions of its secondary mineral assemblage. Building on conclusions from sedimentary observations by the Mars Science Laboratory team, we assume diagenetic, in situ alteration. The modeling shows that the mineral assemblage formed by the reaction of a CO₂-poor and oxidizing, dilute aqueous solution (Gale Portage Water) in an open system with the Fe-rich basaltic-composition sedimentary rocks at 10–50°C and water/rock ratio (mass of rock reacted with the starting fluid) of 100–1000, pH of ~7.5–12. Model alteration assemblages predominantly contain phyllosilicates (Fe-smectite, chlorite), the bulk composition of a mixture of which is close to that of saponite inferred from Chemistry and Mineralogy data and to that of saponite observed in the nakhlite Martian meteorites and terrestrial analogues. To match the observed clay mineral chemistry, inhomogeneous dissolution dominated by the amorphous phase and olivine is required. We therefore deduce a dissolving composition of approximately 70% amorphous material, with 20% olivine, and 10% whole rock component.

  10. Bone mineral density: testing for osteoporosis.

    PubMed

    Sheu, Angela; Diamond, Terry

    2016-04-01

    Primary osteoporosis is related to bone loss from ageing. Secondary osteoporosis results from specific conditions that may be reversible. A thoracolumbar X-ray is useful in identifying vertebral fractures, and dual energy X-ray absorptiometry is the preferred method of calculating bone mineral density. The density of the total hip is the best predictor for a hip fracture, while the lumbar spine is the best site for monitoring the effect of treatment. The T-score is a comparison of the patient's bone density with healthy, young individuals of the same sex. A negative T-score of -2.5 or less at the femoral neck defines osteoporosis. The Z-score is a comparison with the bone density of people of the same age and sex as the patient. A negative Z-score of -2.5 or less should raise suspicion of a secondary cause of osteoporosis. Clinical risk calculators can be used to predict the 10-year probability of a hip or major osteoporotic fracture. A probability of more than 5% for the hip or more than 20% for any fracture is abnormal and treatment may be warranted. PMID:27340320

  11. Diagnosis of secondary caries.

    PubMed

    Kidd, E A

    2001-10-01

    A systematic review of the diagnosis of dental caries was produced before the conference. It did not include the diagnosis of secondary or recurrent caries. This was a wise decision because what little literature exists on the subject potentially clouds the issue. Diagnosis is a mental resting place on the way to a treatment decision. A vital part of caries diagnosis is to decide whether a lesion is active and rapidly progressing or already arrested. This information is essential to plan logical management. However, lesion activity should be judged in the patient. Thus, research on the diagnosis of secondary caries must be carried out in vivo and this usually precludes histological validation. Even if such validation is possible, it has its own problems, particularly in distinguishing recurrent from residual caries. The diagnosis of secondary caries is very important since so many restorations are replaced because dentists think there is a new decay. It will be important to establish valid criteria for the diagnosis of active secondary caries, which will be facilitated by the suggestion that secondary caries is no different from primary caries except that it occurs next to a filling. This implies that it can be seen clinically and on a radiograph, next to a restoration.

  12. Diagnosis of secondary caries.

    PubMed

    Kidd, E A

    2001-10-01

    A systematic review of the diagnosis of dental caries was produced before the conference. It did not include the diagnosis of secondary or recurrent caries. This was a wise decision because what little literature exists on the subject potentially clouds the issue. Diagnosis is a mental resting place on the way to a treatment decision. A vital part of caries diagnosis is to decide whether a lesion is active and rapidly progressing or already arrested. This information is essential to plan logical management. However, lesion activity should be judged in the patient. Thus, research on the diagnosis of secondary caries must be carried out in vivo and this usually precludes histological validation. Even if such validation is possible, it has its own problems, particularly in distinguishing recurrent from residual caries. The diagnosis of secondary caries is very important since so many restorations are replaced because dentists think there is a new decay. It will be important to establish valid criteria for the diagnosis of active secondary caries, which will be facilitated by the suggestion that secondary caries is no different from primary caries except that it occurs next to a filling. This implies that it can be seen clinically and on a radiograph, next to a restoration. PMID:11700003

  13. Secondary metabolites from Ganoderma.

    PubMed

    Baby, Sabulal; Johnson, Anil John; Govindan, Balaji

    2015-06-01

    Ganoderma is a genus of medicinal mushrooms. This review deals with secondary metabolites isolated from Ganoderma and their biological significance. Phytochemical studies over the last 40years led to the isolation of 431 secondary metabolites from various Ganoderma species. The major secondary compounds isolated are (a) C30 lanostanes (ganoderic acids), (b) C30 lanostanes (aldehydes, alcohols, esters, glycosides, lactones, ketones), (c) C27 lanostanes (lucidenic acids), (d) C27 lanostanes (alcohols, lactones, esters), (e) C24, C25 lanostanes (f) C30 pentacyclic triterpenes, (g) meroterpenoids, (h) farnesyl hydroquinones (meroterpenoids), (i) C15 sesquiterpenoids, (j) steroids, (k) alkaloids, (l) prenyl hydroquinone (m) benzofurans, (n) benzopyran-4-one derivatives and (o) benzenoid derivatives. Ganoderma lucidum is the species extensively studied for its secondary metabolites and biological activities. Ganoderma applanatum, Ganoderma colossum, Ganoderma sinense, Ganoderma cochlear, Ganoderma tsugae, Ganoderma amboinense, Ganoderma orbiforme, Ganoderma resinaceum, Ganoderma hainanense, Ganoderma concinna, Ganoderma pfeifferi, Ganoderma neo-japonicum, Ganoderma tropicum, Ganoderma australe, Ganoderma carnosum, Ganoderma fornicatum, Ganoderma lipsiense (synonym G. applanatum), Ganoderma mastoporum, Ganoderma theaecolum, Ganoderma boninense, Ganoderma capense and Ganoderma annulare are the other Ganoderma species subjected to phytochemical studies. Further phytochemical studies on Ganoderma could lead to the discovery of hitherto unknown biologically active secondary metabolites.

  14. [Mineral water as a cure].

    PubMed

    Nocco, Priska Binz

    2008-01-01

    The treatment of diseases with mineral spring water belongs to the oldest medical therapies. The "remedy" mineral water is therefore of importance also within the pharmacy. The present pharmacy historical work examines the impact of the use of mineral waters, as well as of their dried components, as therapeutic agents in the 19th and early 20th centuries, i.e. from approx. 1810 to 1930, as well as the contributions given by pharmacists in the development and analysis of mineral water springs. Beside these aspects, the aim here is also to describe the role played by pharmacists in the production of artificial mineral water as well as in the sale and wholesale of natural and artificial mineral water. In the first part of this work the situation in Switzerland and its surrounding countries, such as Germany, France, Italy and Austria, is discussed. The second part contains a case-study of the particular situation in the Canton Tessin. It is known from the scientific literature published at that time that information on mineral water was frequently reported. Starting from the beginning of the 19th century the number of such publications increased tremendously. The major part of them were publications in scientific journals or contributions to medical and pharmaceutical manuals and reference books. In particular the spa-related literature, such as spa-guides, was of growing interest to a broad public. The inclusion of monographs into the Swiss, the Cantonal as well the foreign pharmacopoeias granted a legal frame for the mineral waters and their dried components. These works are of major importance from a pharmacy historical standpoint and represent a unique proof of historical evidence of the old medicinal drug heritage. The most frequently used therapies based on mineral waters were drinking and bath cures. Several diseases, particularly those of a chronic character, were treated with mineral waters. The positive influence of these cures on the recovery of the patients

  15. The mineral disorders in pediatrics.

    PubMed

    Linshaw, M; Aigbe, M; Kaskel, F

    1998-05-01

    There is increasing awareness of the role that metals/minerals play in health and disease. Minerals contribute in essential ways to the fundamental biochemical and physiological functions of cells. Deficit of an essential mineral leads to aberrations in cell function. Alternatively, minerals in excess have significant toxicity, and in an era of increasing threat to a safe environment, the potential for toxic tissue injury to contribute to progressive renal insufficiency and ultimately to unexplained renal failure remains a major concern. This review provides information on selected minerals that are attracting growing attention with respect to their influence on renal function in health and disease. Although all minerals have the potential to cause toxicity if consumed in sufficient quantity, most are essential nutrients whose deficiency is associated with significant health problems. Certain minerals, including aluminum, arsenic, cadmium, lead, and mercury are considered toxic. Their suggested positive effects on the health of animals has been recently summarized, but in humans they are not currently known to exert any clearly beneficial biological or biochemical effect.

  16. Economic drivers of mineral supply

    USGS Publications Warehouse

    Wagner, Lorie A.; Sullivan, Daniel E.; Sznopek, John L.

    2003-01-01

    The debate over the adequacy of future supplies of mineral resources continues in light of the growing use of mineral-based materials in the United States. According to the U.S. Geological Survey, the quantity of new materials utilized each year has dramatically increased from 161 million tons2 in 1900 to 3.2 billion tons in 2000. Of all the materials used during the 20th century in the United States, more than half were used in the last 25 years. With the Earth?s endowment of natural resources remaining constant, and increased demand for resources, economic theory states that as depletion approaches, prices rise. This study shows that many economic drivers (conditions that create an economic incentive for producers to act in a particular way) such as the impact of globalization, technological improvements, productivity increases, and efficient materials usage are at work simultaneously to impact minerals markets and supply. As a result of these economic drivers, the historical price trend of mineral prices3 in constant dollars has declined as demand has risen. When price is measured by the cost in human effort, the price trend also has been almost steadily downward. Although the United States economy continues its increasing mineral consumption trend, the supply of minerals has been able to keep pace. This study shows that in general supply has grown faster than demand, causing a declining trend in mineral prices.

  17. BET Measurements: Outgassing of Minerals.

    PubMed

    Clausen; Fabricius

    2000-07-01

    Outgassing minerals at elevated temperatures prior to BET measurements can lead to phase changes, especially in the case of amorphous and poorly crystalline materials. In order to evaluate the applicability of the BET method when low outgassing temperatures are required, selected aquifer minerals were outgassed at different temperatures and for different times. The studied minerals are 2-line ferrihydrite, goethite, lepidocrocite, quartz, calcite, alpha-alumina, and kaolinite. The results demonstrate that measured specific surface areas of iron oxides are strongly dependent on outgassing conditions because the surface area increased by 170% with increasing temperature. In the poorly crystalline minerals, phase changes caused by heating were observed at temperatures lower than 100 degrees C. Therefore low outgassing temperatures are preferable for minimizing phase changes. As demonstrated in this study, stable BET values can be obtained by increasing the outgassing time without heating iron oxides. For quartz, calcite, alpha-alumina, and kaolinite, stable BET values were obtained after outgassing the minerals at 100 to 250 degrees C for 2 h. However, outgassing these minerals at room temperature (20 degrees C) only resulted in minor errors, implying that aquifer sediments containing poorly crystalline materials can be outgassed at low temperatures if the outgassing time is increased. Scanning electron microscopy of the studied minerals demonstrated that the particle size as calculated from BET data compares well with particle size observed by scanning electron microscopy images. Copyright 2000 Academic Press.

  18. Microbial mineral colonization across a subsurface redox transition zone

    DOE PAGES

    Converse, Brandon J.; McKinley, James P.; Resch, Charles T.; Roden, Eric E.

    2015-08-28

    Here our study employed 16S rRNA gene amplicon pyrosequencing to examine the hypothesis that chemolithotrophic Fe(II)-oxidizing bacteria (FeOB) would preferentially colonize the Fe(II)-bearing mineral biotite compared to quartz sand when the minerals were incubated in situ within a subsurface redox transition zone (RTZ) at the Hanford 300 Area site in Richland, WA, USA. The work was motivated by the recently documented presence of neutral-pH chemolithotrophic FeOB capable of oxidizing structural Fe(II) in primary silicate and secondary phyllosilicate minerals in 300 Area sediments and groundwater (Benzine et al., 2013). Sterilized portions of sand+biotite or sand alone were incubated in situ formore » 5 months within a multilevel sampling (MLS) apparatus that spanned a ca. 2-m interval across the RTZ in two separate groundwater wells. Parallel MLS measurements of aqueous geochemical species were performed prior to deployment of the minerals. Contrary to expectations, the 16S rRNA gene libraries showed no significant difference in microbial communities that colonized the sand+biotite vs. sand-only deployments. Both mineral-associated and groundwater communities were dominated by heterotrophic taxa, with organisms from the Pseudomonadaceae accounting for up to 70% of all reads from the colonized minerals. These results are consistent with previous results indicating the capacity for heterotrophic metabolism (including anaerobic metabolism below the RTZ) as well as the predominance of heterotrophic taxa within 300 Area sediments and groundwater. Although heterotrophic organisms clearly dominated the colonized minerals, several putative lithotrophic (NH4+, H2, Fe(II), and HS- oxidizing) taxa were detected in significant abundance above and within the RTZ. Such organisms may play a role in the coupling of anaerobic microbial metabolism to oxidative pathways with attendant impacts on elemental cycling and redox-sensitive contaminant behavior in the vicinity of the RTZ.« less

  19. Microbial mineral colonization across a subsurface redox transition zone

    PubMed Central

    Converse, Brandon J.; McKinley, James P.; Resch, Charles T.; Roden, Eric E.

    2015-01-01

    This study employed 16S rRNA gene amplicon pyrosequencing to examine the hypothesis that chemolithotrophic Fe(II)-oxidizing bacteria (FeOB) would preferentially colonize the Fe(II)-bearing mineral biotite compared to quartz sand when the minerals were incubated in situ within a subsurface redox transition zone (RTZ) at the Hanford 300 Area site in Richland, WA, USA. The work was motivated by the recently documented presence of neutral-pH chemolithotrophic FeOB capable of oxidizing structural Fe(II) in primary silicate and secondary phyllosilicate minerals in 300 Area sediments and groundwater (Benzine et al., 2013). Sterilized portions of sand+biotite or sand alone were incubated in situ for 5 months within a multilevel sampling (MLS) apparatus that spanned a ca. 2-m interval across the RTZ in two separate groundwater wells. Parallel MLS measurements of aqueous geochemical species were performed prior to deployment of the minerals. Contrary to expectations, the 16S rRNA gene libraries showed no significant difference in microbial communities that colonized the sand+biotite vs. sand-only deployments. Both mineral-associated and groundwater communities were dominated by heterotrophic taxa, with organisms from the Pseudomonadaceae accounting for up to 70% of all reads from the colonized minerals. These results are consistent with previous results indicating the capacity for heterotrophic metabolism (including anaerobic metabolism below the RTZ) as well as the predominance of heterotrophic taxa within 300 Area sediments and groundwater. Although heterotrophic organisms clearly dominated the colonized minerals, several putative lithotrophic (NH4+, H2, Fe(II), and HS- oxidizing) taxa were detected in significant abundance above and within the RTZ. Such organisms may play a role in the coupling of anaerobic microbial metabolism to oxidative pathways with attendant impacts on elemental cycling and redox-sensitive contaminant behavior in the vicinity of the RTZ. PMID

  20. Microbial mineral colonization across a subsurface redox transition zone

    SciTech Connect

    Converse, Brandon J.; McKinley, James P.; Resch, Charles T.; Roden, Eric E.

    2015-08-28

    Here our study employed 16S rRNA gene amplicon pyrosequencing to examine the hypothesis that chemolithotrophic Fe(II)-oxidizing bacteria (FeOB) would preferentially colonize the Fe(II)-bearing mineral biotite compared to quartz sand when the minerals were incubated in situ within a subsurface redox transition zone (RTZ) at the Hanford 300 Area site in Richland, WA, USA. The work was motivated by the recently documented presence of neutral-pH chemolithotrophic FeOB capable of oxidizing structural Fe(II) in primary silicate and secondary phyllosilicate minerals in 300 Area sediments and groundwater (Benzine et al., 2013). Sterilized portions of sand+biotite or sand alone were incubated in situ for 5 months within a multilevel sampling (MLS) apparatus that spanned a ca. 2-m interval across the RTZ in two separate groundwater wells. Parallel MLS measurements of aqueous geochemical species were performed prior to deployment of the minerals. Contrary to expectations, the 16S rRNA gene libraries showed no significant difference in microbial communities that colonized the sand+biotite vs. sand-only deployments. Both mineral-associated and groundwater communities were dominated by heterotrophic taxa, with organisms from the Pseudomonadaceae accounting for up to 70% of all reads from the colonized minerals. These results are consistent with previous results indicating the capacity for heterotrophic metabolism (including anaerobic metabolism below the RTZ) as well as the predominance of heterotrophic taxa within 300 Area sediments and groundwater. Although heterotrophic organisms clearly dominated the colonized minerals, several putative lithotrophic (NH4+, H2, Fe(II), and HS- oxidizing) taxa were detected in significant abundance above and within the RTZ. Such organisms may play a role in the coupling of anaerobic microbial metabolism to oxidative pathways with attendant impacts on elemental cycling and redox-sensitive contaminant

  1. Secondary drowning in children.

    PubMed

    Pearn, J H

    1980-10-25

    Secondary drowning (and near-drowning) is one of the post-immersion respiratory syndromes. It is defined as deterioration of pulmonary function that follows deficient gas exchange due to loss or inactivation of surfactant. A review of 94 consecutive cases of near-drowning in childhood showed that this syndrome occurred in five (5%) cases. Its onset was usually rapid and characterised by a latent period of one to 48 hours of relative respiratory well-being. It occurred more rapidly after immersion in fresh water. The two children immersed in salt water died of secondary drowning, while the three immersed in fresh water recovered completely. If it is anticipated, recognised, and treated vigorously prognosis of secondary drowning is good in fresh water cases but bad after salt water immersion.

  2. Mineral Commodity Profiles -- Rubidium

    USGS Publications Warehouse

    Butterman, W.C.; Reese, R.G.

    2003-01-01

    Overview -- Rubidium is a soft, ductile, silvery-white metal that melts at 39.3 ?C. One of the alkali metals, it is positioned in group 1 (or IA) of the periodic table between potassium and cesium. Naturally occurring rubidium is slightly radioactive. Rubidium is an extremely reactive metal--it ignites spontaneously in the presence of air and decomposes water explosively, igniting the liberated hydrogen. Because of its reactivity, the metal and several of its compounds are hazardous materials, and must be stored and transported in isolation from possible reactants. Although rubidium is more abundant in the earth?s crust than copper, lead, or zinc, it forms no minerals of its own, and is, or has been, produced in small quantities as a byproduct of the processing of cesium and lithium ores taken from a few small deposits in Canada, Namibia, and Zambia. In the United States, the metal and its compounds are produced from imported raw materials by at least one company, the Cabot Corporation (Cabot, 2003). Rubidium is used interchangeably or together with cesium in many uses. Its principal application is in specialty glasses used in fiber optic telecommunication systems. Rubidium?s photoemissive properties have led to its use in night-vision devices, photoelectric cells, and photomultiplier tubes. It has several uses in medical science, such as in positron emission tomographic (PET) imaging, the treatment of epilepsy, and the ultracentrifugal separation of nucleic acids and viruses. A dozen or more other uses are known, which include use as a cocatalyst for several organic reactions and in frequency reference oscillators for telecommunications network synchronization. The market for rubidium is extremely small, amounting to 1 to 2 metric tons per year (t/yr) in the United States. World resources are vast compared with demand.

  3. Glycine Polymerization on Oxide Minerals

    NASA Astrophysics Data System (ADS)

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

    2016-07-01

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

  4. 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.

  5. Use of fracture filling mineral assemblages for characterizing water-rock interactions during exhumation of an accretionary complex: An example from the Shimanto Belt, southern Kyushu Japan

    NASA Astrophysics Data System (ADS)

    Ono, Takuya; Yoshida, Hidekazu; Metcalfe, Richard

    2016-06-01

    Various fracture filling minerals and secondary minerals in fracture walls were formed by fluid-rock interaction during the exhumation of the Palaeogene Shimanto Belt of Kyushu, Japan, which is located in an accretionary complex. Each mineral formed under favourable geological conditions and can be used to estimate the conditions of accretion and formation of the related rock sequences. Petrographic observations, mineralogical and geochemical analyses were made on fracture filling minerals and secondary minerals from boreholes of ca. 140 m depth, drilled in the Shimanto Belt. Results reveal that the secondary minerals were formed in three major stages distinguished by the sequential textural relationships of the minerals and the interpreted environment of mineral formation. Filling mineral assemblages show that the studied rock formation has been subducted to a depth of several km and the temperature reached was ca. 200-300 °C. After the subduction, the rock formation was uplifted and surface acidic water penetrated up to 80 m beneath the present ground surface. The acid water dissolved calcite fracture filling minerals to form the present groundwater flow-paths, which allowed recent wall rock alteration to occur. The results shown here imply that filling mineral assemblages can be an effective tool to evaluate the environmental changes during exhumation of an accretionary complex.

  6. Mineral sources and transport pathways for arsenic release in a coastal watershed, USA

    USGS Publications Warehouse

    Foley, Nora K.; Ayuso, Robert A.

    2008-01-01

    Metasedimentary bedrock of coastal Maine contains a diverse suite of As-bearing minerals that act as significant sources of elements found in ground and surface waters in the region. Arsenic sources in the Penobscot Formation include, in order of decreasing As content by weight: löllingite and realgar (c.70%), arsenopyrite, cobaltite, glaucodot, and gersdorffite (in the range of 34–45%), arsenian pyrite (<4%), and pyrrhotite (<0.15%). In the Penobscot Formation, the relative stability of primary As-bearing minerals follows a pattern where the most commonly observed highly altered minerals are pyrrhotite, realgar, niccolite, löllingite > glaucodot, arsenopyrite-cobaltian > arsenopyrite, cobaltite, gersdorffite, fine-grained pyrite, Ni-pyrite > coarse-grained pyrite. Reactions illustrate that oxidation of Fe-As disulphide group and As-sulphide minerals is the primary release process for As. Liberation of As by carbonation of realgar and orpiment in contact with high-pH groundwaters may contribute locally to elevated contents of As in groundwater, especially where As is decoupled from Fe. Released metals are sequestered in secondary minerals by sorption or by incorporation in crystal structures. Secondary minerals acting as intermediate As reservoirs include claudetite (c.75%), orpiment (61%), scorodite (c. 45%), secondary arsenopyrite (c. 46%), goethite (<4490 ppm), natrojarosite (<42 ppm), rosenite, melanterite, ferrihydrite, and Mn-hydroxide coatings. Some soils also contain Fe-Co-Ni-arsenate, Ca-arsenate, and carbonate minerals. Reductive dissolution of Fe-oxide minerals may govern the ultimate release of iron and arsenic – especially As(V) – to groundwater; however, dissolution of claudetite (arsenic trioxide) may directly contribute As(III). Processes thought to explain the release of As from minerals in bedrock include oxidation of arsenian pyrite or arsenopyrite, or carbonation of As-sulphides, and most models based on these generally rely on

  7. Fragrance sensitivity in coal miners.

    PubMed

    Goodfield, M J; Saihan, E M

    1988-02-01

    In a prospective study, we have examined the incidence of fragrance sensitivity in Nottinghamshire coal miners. Our results confirm previous reports of an increased incidence of such sensitivity in miners (45%) when compared with both male (20%) and female (13%) non-miners. This increased incidence is not related to an increased use of perfumed cosmetics, but may be related to the use of a highly perfumed body lotion in subjects who already have a high incidence of irritant hand eczema. There was no significant increase in the rate of positive reactions to other applied allergens.

  8. Quantification of Secondary Metabolites.

    PubMed

    2016-01-01

    Plants are a rich source of secondary metabolites that have medicinal and aromatic properties. Secondary metabolites such as alkaloids, iridoids and phenolics generally produced by plants for their defence mechanisms have been implicated in the therapeutic properties of most medicinal plants. Hence, quantification of these metabolites will aid to discover new and effective drugs from plant sources and also to scientifically validate the existing traditional practices. Quantification of large group of phytochemicals such as phenolics and flavonoids is quantified in this context. PMID:26939265

  9. 76 FR 44892 - Information Collection; Locatable Minerals

    Federal Register 2010, 2011, 2012, 2013, 2014

    2011-07-27

    ... Forest Service Information Collection; Locatable Minerals AGENCY: Forest Service, USDA. ACTION: Notice... approved information collection, Locatable Minerals-36 CFR part 228, subpart A. DATES: Comments must be... entry to the building. FOR FURTHER INFORMATION CONTACT: Tony Ferguson, Director, Minerals and...

  10. Mineral Losses During Extreme Environmental Conditions

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Advisory groups that make recommendations for mineral intakes continue to identify accurate determinations of sweat mineral losses during physical activity as a critical void in their deliberations. Although estimates of sweat mineral concentrations are available, they are highly variable. Practica...

  11. Assessment of the geoavailability of trace elements from selected zinc minerals

    USGS Publications Warehouse

    Driscoll, Rhonda L.; Hageman, Phillip L.; Benzel, William M.; Diehl, Sharon F.; Morman, Suzette; Choate, LaDonna M.; Lowers, Heather

    2014-01-01

    This assessment focused on five zinc-bearing minerals. The minerals were subjected to a number of analyses including quantitative X-ray diffraction, optical microscopy, leaching tests, and bioaccessibility and toxicity studies. Like a previous comprehensive assessment of five copper-bearing minerals, the purpose of this assessment was to obtain structural and chemical information and to characterize the reactivity of each mineral to various simulated environmental and biological conditions. As in the copper minerals study, analyses were conducted consistent with widely accepted methods. Unless otherwise noted, analytical methods used for this study were identical to those described in the investigation of copper-bearing minerals. Two sphalerite specimens were included in the zinc-minerals set. One sphalerite was recovered from a mine in Balmat, New York; the second came from a mine in Creede, Colorado. The location and conditions of origin are significant because, as analyses confirmed, the two sphalerite specimens are quite different. For example, data acquired from a simulated gastric fluid (SGF) study indicate that the hydrothermally formed Creede sphalerite contains orders of magnitude higher arsenic, cadmium, manganese, and lead than the much older metamorphic Balmat sphalerite. The SGF and other experimental results contained in this report suggest that crystallizing conditions such as temperature, pressure, fluidization, or alteration processes significantly affect mineral properties—properties that, in turn, influence reactivity, solubility, and toxicity. The three remaining minerals analyzed for this report—smithsonite, hemimorphite, and hydrozincite—are all secondary minerals or alteration products of zinc-ore deposits. In addition, all share physical characteristics such as tenacity, density, streak, and cleavage. Similarities end there. The chemical composition, unit-cell parameters, acid-neutralizing potential, and other observable and

  12. Mineral and water nutrition.

    PubMed

    Beede, D K

    1991-07-01

    In providing minerals to dairy cattle it is important to distinguish between dietary requirements and feeding recommendations. The requirement is the absolute amount of an element needed to meet the animal's metabolic needs for maintenance, growth, pregnancy, and lactation divided by the coefficient of absorption; this is estimated by the factorial method. Actual estimates of requirements for lactating dairy cattle have been determined for Ca and P. The major difficulties in relying on the requirement estimate are that dry matter intake varies and the true absorption coefficient of the mixture of feeds in the ration generally is unknown. Therefore, feeding recommendations, based on feeding graded concentrations of an element, often offer more applicable information. With the exception of Ca and P, the current feeding recommendations for the other macrominerals, Mg, Na, K, Cl and S, have resulted from feeding trials. With certain environmental and physiologic situations the feeding recommendations may vary. For example, during heat stress the dietary K recommendation for the lactating cow should be higher than in cool weather because of increased sweating and decreased feed intake. Another example may be that the source of supplemental Mg may affect what dietary inclusion rate will yield optimal performance and should be recommended. An important consideration in dairy ration formulation in the future will address the interrelationships of the various macrominerals. There is accumulating evidence that shows that different concentrations of Na, Cl, and K may interrelate and affect lactational performance. Many times the naturally occurring concentrations of one or more of these elements may have to be associated with varying concentrations of the others in order to optimize animal performance and health. Much experimentation likely will examine these interrelationships in the future. Supplementation of trace elements in diets of dairy cattle is common practice. This

  13. Highwall miners pursue thinner seams

    SciTech Connect

    Fiscor, S.

    2006-04-15

    OEMs have implemented design changes to reduce the machine's footprint and to mine more accurately. Three manufacturers offer highwall mining systems, American Highwall Systems (AMS), ICG Addcar and Superior Highwall Miners. Latest developments in their machines are reported. 3 photos.

  14. 77 FR 56273 - Conflict Minerals

    Federal Register 2010, 2011, 2012, 2013, 2014

    2012-09-12

    ..., Release No. 34-63547 (Dec. 15, 2010) [75 FR 80948] (the ``Proposing Release''). \\5\\ Public Law 111-203... (Jan. 7, 2011) (``WGC I''). \\33\\ Conflict Minerals, Release No. 34-63793 (Jan. 28, 2011) [76 FR...

  15. Secondary Emergency Visits

    PubMed Central

    Mohr, Bruce; Wiley, Preston

    1991-01-01

    This study surveyed patients seeking emergency care at three Calgary hospitals during a 7-day period in February 1989. Twenty-one percent had seen another physician for the same medical problem within 72 hours. The study suggests that secondary visits at emergency departments affect health care costs. Further study is needed to investigate the extent and appropriateness of such visits. PMID:21229002

  16. Hebrew for Secondary Schools.

    ERIC Educational Resources Information Center

    Moskowitz, Solomon

    This teacher's handbook for Hebrew instruction in secondary Schools, designed for use in public schools, is patterned after New York State Education Department handbooks for French, Spanish, and German. Sections include: (1) teaching the four skills, (2) speaking, (3) audiolingual experiences, (4) suggested content and topics for audiolingual…

  17. Cosmetology. Secondary Curriculum Guide.

    ERIC Educational Resources Information Center

    Moye, Michael D.; And Others

    This curriculum guide is designed to offer guidelines along with supporting resources and teaching ideas from which the local secondary instructor can extract a cosmetology curriculum that meets local needs. Following an outline of the philosophy and goals underlying state and local vocational education programs in Georgia, the purpose and…

  18. Secondary Dance Instructional Guide.

    ERIC Educational Resources Information Center

    Montgomery County Public Schools, Rockville, MD. Dept. of Instructional Planning and Development.

    This manual provides guidelines for dance teachers in secondary schools. A brief statement is made on the purpose and philosophy of dance education, and activities and instructional suggestions are presented for various dance forms: (1) group dance--folk/ethnic, square dance, and social dance; (2) aerobic dance; (3) jazz dance; (4) modern dance;…

  19. Aircraft Electric Secondary Power

    NASA Technical Reports Server (NTRS)

    1983-01-01

    Technologies resulted to aircraft power systems and aircraft in which all secondary power is supplied electrically are discussed. A high-voltage dc power generating system for fighter aircraft, permanent magnet motors and generators for aircraft, lightweight transformers, and the installation of electric generators on turbine engines are among the topics discussed.

  20. Scheduling the Secondary School.

    ERIC Educational Resources Information Center

    Dempsey, Richard A.; Traverso, Henry P.

    This "how-to-do-it" manual on the intricacies of school scheduling offers both technical information and common sense advice about the process of secondary school scheduling. The first of six chapters provides an overview of scheduling; chapter 2 examines specific considerations for scheduling; chapter 3 surveys the scheduling models and their…

  1. Modernising Portugal's Secondary Schools

    ERIC Educational Resources Information Center

    Heitor, Teresa V.

    2008-01-01

    Portugal has a total of 477 public secondary schools. Some date from the end of the 19th century but the majority were built after 1970, reflecting the period of expansion in the school network and the extension of compulsory schooling. The schools are heterogeneous in terms of building types, architectural features and quality. An assessment of…

  2. Secondary Education in Austria.

    ERIC Educational Resources Information Center

    Aigner, Helmut

    This booklet provides a brief description of secondary education in Austria. The publication is part of a series that seeks to make the public aware of the education systems and traditions in all signatory states to the European Cultural Convention and to outline the essential problems these systems presently are facing. This short booklet…

  3. Secondary School Languages: Spanish.

    ERIC Educational Resources Information Center

    British Columbia Dept. of Education, Victoria.

    This curriculum guide outlines three programs for secondary school Spanish instruction, each program covering grades 9, 10, and 11 in British Columbian schools. Each outline specifies basic texts, supplementary readings, and teaching aids. In addition, a very basic outline of a beginner's Spanish 11 is offered, and a Spanish 12 literature course…

  4. Secondary Services in Physics.

    ERIC Educational Resources Information Center

    Cooper, Marianne; Terry, Edward

    The basic characteristics of sixty-nine secondary services in physics were analyzed in terms of sponsorship and distribution by: (1) country of origin, (2) language, (3) age, (4) frequency of publication, (5) subject and geographical coverage and (6) size. The eight major services, in terms of size, are identified. The use of the services by the…

  5. Preventing Secondary Conditions.

    ERIC Educational Resources Information Center

    Pope, Andrew M.

    1992-01-01

    This paper presents the Institute of Medicine model of the dynamic nature of the disabling process of both primary disabilities and secondary conditions, and the interaction of that process with risk factors and quality of life. The components of a comprehensive disability prevention program are discussed. (Author/JDD)

  6. Secondary Syphilitic Lesions

    PubMed Central

    Baughn, Robert E.; Musher, Daniel M.

    2005-01-01

    An important theme that emerges from all early historical accounts is that in addition to the decreased virulence of Treponema pallidum, the incidence of secondary syphilis has decreased drastically over the past three centuries. Even in the early 20th century, most syphilologists were of the opinion that the disease had undergone changes in its manifestations and that they were dealing with an attenuated form of the spirochete. Such opinions were based primarily on the observations that violent cutaneous reactions and fatalities associated with the secondary stage had become extremely rare. The rate of primary and secondary syphilis in the United States increased in 2002 for the second consecutive year. After a decade-long decline that led to an all-time low in 2000, the recent trend is attributable, to a large extent, by a increase in reported syphilis cases among men, particularly homosexual and bisexual men having sex with men. The present review addresses the clinical and diagnostic criteria for the recognition of secondary syphilis, the clinical course and manifestations of the disease if allowed to proceed past the primary stage of disease in untreated individuals, and the treatment for this stage of the disease. PMID:15653827

  7. Secondary optic nerve tumors.

    PubMed

    Christmas, N J; Mead, M D; Richardson, E P; Albert, D M

    1991-01-01

    Secondary tumors of the optic nerve are more common than primary optic nerve tumors. The involvement of the optic nerve may arise from direct invasion from intraocular malignancies, from hematopoietic malignancy, from meningeal carcinomatosis, or from distant primary tumors. Orbital tumors rarely invade the optic nerve, and brain tumors involve it only in their late stages.

  8. Subarctic weathering of mineral wastes provides a sink for atmospheric CO(2).

    PubMed

    Wilson, Siobhan A; Dipple, Gregory M; Power, Ian M; Barker, Shaun L L; Fallon, Stewart J; Southam, Gordon

    2011-09-15

    The mineral waste from some mines has the capacity to trap and store CO(2) within secondary carbonate minerals via the process of silicate weathering. Nesquehonite [MgCO(3)·3H(2)O] forms by weathering of Mg-silicate minerals in kimberlitic mine tailings at the Diavik Diamond Mine, Northwest Territories, Canada. Less abundant Na- and Ca-carbonate minerals precipitate from sewage treatment effluent deposited in the tailings storage facility. Radiocarbon and stable carbon and oxygen isotopes are used to assess the ability of mine tailings to trap and store modern CO(2) within these minerals in the arid, subarctic climate at Diavik. Stable isotopic data cannot always uniquely identify the source of carbon stored within minerals in this setting; however, radiocarbon isotopic data provide a reliable quantitative estimate for sequestration of modern carbon. At least 89% of the carbon trapped within secondary carbonate minerals at Diavik is derived from a modern source, either by direct uptake of atmospheric CO(2) or indirect uptake though the biosphere. Silicate weathering at Diavik is trapping 102-114 g C/m(2)/y within nesquehonite, which corresponds to a 2 orders of magnitude increase over the background rate of CO(2) uptake predicted from arctic and subarctic river catchment data. PMID:21854037

  9. The Zapot pegmatite mineral county

    USGS Publications Warehouse

    Foord, E.E.; Soregaroli, A.E.; Gordon, H.M.

    1999-01-01

    The Zapot pegmatite is currently being mined for mineral specimens (chiefly amazonite, topaz and smoky quartz in miarolitic cavities), for gemstones (topaz and smoky quartz) and for decorative rock (amazonite). The deposit is owned and operated by Harvey Gordon Minerals of Reno, Nevada, and is the only amazonite-topaz mining operation in the state. Thousands of specimens from this operation have reached the collector market.

  10. Mineral of the month: magnesium

    USGS Publications Warehouse

    Kramer, Deborah A.

    2005-01-01

    Magnesium, often confused with last month’s mineral of the month manganese, is valued primarily because of its light weight and high strength-to-weight ratio. Magnesium is the eighth most abundant element and constitutes about 2 percent of the Earth’s crust. It is the third most plentiful element dissolved in seawater, with a concentration averaging 0.13 percent. Magnesium is found in over 60 minerals, and also is recovered from seawater, wells, and lake brines and bitterns.

  11. Secondary impact hazard assessment

    NASA Technical Reports Server (NTRS)

    1986-01-01

    A series of light gas gun shots (4 to 7 km/sec) were performed with 5 mg nylon and aluminum projectiles to determine the size, mass, velocity, and spatial distribution of spall and ejecta from a number of graphite/epoxy targets. Similar determinations were also performed on a few aluminum targets. Target thickness and material were chosen to be representative of proposed Space Station structure. The data from these shots and other information were used to predict the hazard to Space Station elements from secondary particles resulting from impacts of micrometeoroids and orbital debris on the Space Station. This hazard was quantified as an additional flux over and above the primary micrometeoroid and orbital debris flux that must be considered in the design process. In order to simplify the calculations, eject and spall mass were assumed to scale directly with the energy of the projectile. Other scaling systems may be closer to reality. The secondary particles considered are only those particles that may impact other structure immediately after the primary impact. The addition to the orbital debris problem from these primary impacts was not addressed. Data from this study should be fed into the orbital debris model to see if Space Station secondaries make a significant contribution to orbital debris. The hazard to a Space Station element from secondary particles above and beyond the micrometeoroid and orbital debris hazard is categorized in terms of two factors: (1) the 'view factor' of the element to other Space Station structure or the geometry of placement of the element, and (2) the sensitivity to damage, stated in terms of energy. Several example cases were chosen, the Space Station module windows, windows of a Shuttle docked to the Space Station, the habitat module walls, and the photovoltaic solar cell arrays. For the examples chosen the secondary flux contributed no more than 10 percent to the total flux (primary and secondary) above a given calculated

  12. Intermediate-depth earthquake generation: what hydrous minerals can tell us

    NASA Astrophysics Data System (ADS)

    Deseta, N.; Ashwal, L.; Andersen, T. B.

    2012-04-01

    Subduction zone seismicity has commonly been causally related to the dehydration of minerals within the subducting slab(Hacker et al. 2004, Jung et al. (2004), Dobson et al. 2002, Rondenay et al. 2008). Other models for release of intermediate- and deep earthquakes include spontaneous reaction(s) affecting large rock-bodies along overstepped phase boundaries ( e.g. Green and Houston, 1995) and various shear heating-localization models (e.g. Kelemen and Hirth 2007, John et al. 2009). These concepts are principally reliant on seismic and thermo-petrological modeling; both of which are indirect methods of analysis. Recent discoveries of pseudotachylytes (PST) formed under high pressure conditions (Ivrea-Verbano Zone, Italy, Western Gneiss Region, Norway and Corsica) provide the first tangible opportunity to evaluate these models (Austrheim and Andersen, 2004, Lund and Austrheim, 2003, Obata and Karato, 1995, Jin et al., 1998). This case study focuses on observations based on ultramafic and mafic PST within the Ligurian Ophiolite of the high pressure-low temperature metamorphic (HP-LT) 'Shistes Lustres' complex in Cima di Gratera, Corsica (Andersen et al. 2008). These PST have been preserved in pristine lenses of peridotite and gabbro surrounded by schistose serpentinites. The PST range in thickness from 1mm to 25 cm (Andersen and Austrheim, 2006). Petrography and geochemistry on PST from the peridotite and gabbro samples indicates that total/near-total fusion of the local host rock mineral assemblage occurred; bringing up the temperature of shear zone from 350° C to 1400 - 1700° C; depending on the host rock (Andersen and Austrheim, 2006). The composition of the PST is highly variable, even at the thin section scale and this has been attributed to the coarse-grained nature of the host rock, its small scale inhomogeneity and poor mixing of the fusion melt. Almost all the bulk analyses of the PST are hydrous; the peridotitic PST is always hydrous (H2O content from 3

  13. Influence of abiotic stress signals on secondary metabolites in plants

    PubMed Central

    Ramakrishna, Akula; Ravishankar, Gokare Aswathanarayana

    2011-01-01

    Plant secondary metabolites are unique sources for pharmaceuticals, food additives, flavors, and industrially important biochemicals. Accumulation of such metabolites often occurs in plants subjected to stresses including various elicitors or signal molecules. Secondary metabolites play a major role in the adaptation of plants to the environment and in overcoming stress conditions. Environmental factors viz. temperature, humidity, light intensity, the supply of water, minerals, and CO2 influence the growth of a plant and secondary metabolite production. Drought, high salinity, and freezing temperatures are environmental conditions that cause adverse effects on the growth of plants and the productivity of crops. Plant cell culture technologies have been effective tools for both studying and producing plant secondary metabolites under in vitro conditions and for plant improvement. This brief review summarizes the influence of different abiotic factors include salt, drought, light, heavy metals, frost etc. on secondary metabolites in plants. The focus of the present review is the influence of abiotic factors on secondary metabolite production and some of important plant pharmaceuticals. Also, we describe the results of in vitro cultures and production of some important secondary metabolites obtained in our laboratory. PMID:22041989

  14. Influence of abiotic stress signals on secondary metabolites in plants.

    PubMed

    Ramakrishna, Akula; Ravishankar, Gokare Aswathanarayana

    2011-11-01

    Plant secondary metabolites are unique sources for pharmaceuticals, food additives, flavors, and industrially important biochemicals. Accumulation of such metabolites often occurs in plants subjected to stresses including various elicitors or signal molecules. Secondary metabolites play a major role in the adaptation of plants to the environment and in overcoming stress conditions. Environmental factors viz. temperature, humidity, light intensity, the supply of water, minerals, and CO2 influence the growth of a plant and secondary metabolite production. Drought, high salinity, and freezing temperatures are environmental conditions that cause adverse effects on the growth of plants and the productivity of crops. Plant cell culture technologies have been effective tools for both studying and producing plant secondary metabolites under in vitro conditions and for plant improvement. This brief review summarizes the influence of different abiotic factors include salt, drought, light, heavy metals, frost etc. on secondary metabolites in plants. The focus of the present review is the influence of abiotic factors on secondary metabolite production and some of important plant pharmaceuticals. Also, we describe the results of in vitro cultures and production of some important secondary metabolites obtained in our laboratory.

  15. Fate of organo-mineral particles in streams: Microbial degradation by streamwater & biofilm assemblages

    NASA Astrophysics Data System (ADS)

    Hunter, W. R.; Raich, M.; Wanek, W.; Battin, T. J.

    2013-12-01

    Inland waters are of global biogeochemical importance. They receive carbon inputs of ~ 4.8 Pg C/ y of which, 12 % is buried, 18 % transported to the oceans, and 70 % supports aquatic secondary production. However, the mechanisms that determine the fate of organic matter (OM) in these systems are poorly defined. One aspect of this is the formation of organo-mineral complexes in aquatic systems and their potential as a route for OM transport and burial vs. their use as carbon (C) and nitrogen (N) sources within aquatic systems. Organo-mineral particles form by sorption of dissolved OM to freshly eroded mineral surfaces and may contribute to ecosystem-scale particulate OM fluxes. We experimentally tested the availability of mineral-sorbed OM as a C & N source for streamwater microbial assemblages and streambed biofilms. Organo-mineral particles were constructed in vitro by sorption of 13C:15N-labelled amino acids to hydrated kaolin particles, and microbial degradation of these particles compared with equivalent doses of 13C:15N-labelled free amino acids. Experiments were conducted in 120 ml mesocosms over 7 days using biofilms and water sampled from the Oberer Seebach stream (Austria). Each incubation experienced a 16:8 light:dark regime, with metabolism monitored via changes in oxygen concentrations between photoperiods. The relative fate of the organo-mineral particles was quantified by tracing the mineralization of the 13C and 15N labels and their incorporation into microbial biomass. Here we present the initial results of 13C-label mineralization, incorporation and retention within dissolved organic carbon pool. The results indicate that 514 (× 219) μmol/ mmol of the 13:15N labeled free amino acids were mineralized over the 7-day incubations. By contrast, 186 (× 97) μmol/ mmol of the mineral-sorbed amino acids were mineralized over a similar period. Thus, organo-mineral complexation reduced amino acid mineralization by ~ 60 %, with no differences observed

  16. Mineral commodity profiles: nitrogen

    USGS Publications Warehouse

    Kramer, Deborah A.

    2004-01-01

    Overview -- Nitrogen (N) is an essential element of life and a part of all animal and plant proteins. As a part of the DNA and RNA molecules, nitrogen is an essential constituent of each individual's genetic blueprint. As an essential element in the chlorophyll molecule, nitrogen is vital to a plant's ability to photosynthesize. Some crop plants, such as alfalfa, peas, peanuts, and soybeans, can convert atmospheric nitrogen into a usable form by a process referred to as 'fixation.' Most of the nitrogen that is available for crop production, however, comes from decomposing animal and plant waste or from commercially produced fertilizers. Commercial fertilizers contain nitrogen in the form of ammonium and/or nitrate or in a form that is quickly converted to the ammonium or nitrate form once the fertilizer is applied to the soil. Ammonia is generally the source of nitrogen in fertilizers. Anhydrous ammonia is commercially produced by reacting nitrogen with hydrogen under high temperatures and pressures. The source of nitrogen is the atmosphere, which is almost 80 percent nitrogen. Hydrogen is derived from a variety of raw materials, which include water, and crude oil, coal, and natural gas hydrocarbons. Nitrogen-based fertilizers are produced from ammonia feedstocks through a variety of chemical processes. Small quantities of nitrates are produced from mineral resources principally in Chile. In 2002, anhydrous ammonia and other nitrogen materials were produced in more than 70 countries. Global ammonia production was 108 million metric tons (Mt) of contained nitrogen. With 28 percent of this total, China was the largest producer of ammonia. Asia contributed 46 percent of total world ammonia production, and countries of the former U.S.S.R. represented 13 percent. North America also produced 13 percent of the total; Western Europe, 9 percent; the Middle East, 7 percent; Central America and South America, 5 percent; Eastern Europe, 3 percent; and Africa and Oceania

  17. Mineral-resource data bases

    USGS Publications Warehouse

    ,

    1997-01-01

    Data bases are essential for modern scientific research. The new and exciting work being done in the Mineral Resource Program in the U.S. Geological Survey (USGS) usually begins with the question, "Where are the known deposits?" A mineral-resource data base containing this type of information and more can be useful not just to USGS scientists, but to anyone who needs such data. Users of the data bases from outside the USGS include mining and exploration companies, environmental groups, academia, other Federal Agencies, and the general public. At present, the USGS has two large mineral-resource data bases, MRDS (Mineral Resource Data System) and MAS (Minerals Availability System). MRDS was built and is mamtained by the USGS, and MAS was built and maintained by the Bureau of Mines. In 1996, after the Bureau was abolished, MAS was transferred to the USGS. The two data bases were compiled for different purposes and contain very different mformation. For instance, MAS contains information on costs, details of mining methods, and feasibility studies. MRDS has mineralogical and geologic data that are not contained in MAS. Because they are both mineral-resource data bases, however, they contain some information in common, such as location, name(s) of sites, and commodities present. Both data bases are international in scope, and both are quite large. MRDS contains over 110,000 records, while MAS has over 220,000. One reason that MAS has more records is that it contains information on smelters, mill sites, and fossil fuel sites, as well as mineral- resource sites. The USGS is working to combine the information in both data bases. This is a large undertaking that will require some years to complete. In the interim, information from both data bases will still be available

  18. 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.

  19. Biosolids-derived nitrogen mineralization and transformation in forest soils.

    PubMed

    Wang, Hailong; Kimberley, Mark O; Schlegelmilch, Mirko

    2003-01-01

    Utilization of biosolids through land application is becoming increasingly popular among wastewater managers. To minimize the potential contamination of receiving waters from biosolids-derived nitrogen (N), it is important to understand the availability of N after land application of biosolids. In this study, four secondary biosolids (two municipal and two pulp and paper industrial biosolids) were used in a laboratory incubation experiment to simulate N mineralization and transformation after land application. Municipal biosolids were from either aerobically or anaerobically digested sources, while pulp and paper industrial biosolids were from aerated wastewater stabilization lagoons. These biosolids were mixed with two New Zealand forest soils (top 100 mm of a volcanic soil and a brown soil) and incubated at two temperatures (10 and 20 degrees C) for 26 wk. During incubation, mineralized N was periodically leached from the soil-biosolids mixture with 0.01 M CaCl2 solution and concentrations of NH4 and NO3 in leachate were determined. Mineralization of N from aerobically digested municipal biosolids (32.1%) was significantly more than that from anaerobically digested biosolids (15.2%). Among the two pulp and paper industrial biosolids, little N leached from one, while as much as 18.0% of total organic N was leached from the other. As expected, mineralization of N was significantly greater at 20 degrees C (average 22.8%) than at 10 degrees C (average 9.7%). It was observed that more N in municipal biosolids was mineralized in the brown soil, whereas more N in pulp and paper industrial biosolids mineralized in the volcanic soil. Transformation of NH4 to NO3 was affected by soil type and temperature. PMID:14535329

  20. Secondary hypertension in adults

    PubMed Central

    Puar, Troy Hai Kiat; Mok, Yingjuan; Debajyoti, Roy; Khoo, Joan; How, Choon How; Ng, Alvin Kok Heong

    2016-01-01

    Secondary hypertension occurs in a significant proportion of adult patients (~10%). In young patients, renal causes (glomerulonephritis) and coarctation of the aorta should be considered. In older patients, primary aldosteronism, obstructive sleep apnoea and renal artery stenosis are more prevalent than previously thought. Primary aldosteronism can be screened by taking morning aldosterone and renin levels, and should be considered in patients with severe, resistant or hypokalaemia-associated hypertension. Symptoms of obstructive sleep apnoea should be sought. Worsening of renal function after starting an angiotensin-converting enzyme inhibitor suggests the possibility of renal artery stenosis. Recognition, diagnosis and treatment of secondary causes of hypertension lead to good clinical outcomes and the possible reversal of end-organ damage, in addition to blood pressure control. As most patients with hypertension are managed at the primary care level, it is important for primary care physicians to recognise these conditions and refer patients appropriately. PMID:27211205

  1. Developmental haemostasis: secondary haemostasis.

    PubMed

    Monagle, Paul; Massicotte, Patricia

    2011-12-01

    The haemostatic system is a complex interaction between the vasculature, cellular components and plasma proteins that interact to maintain haemostasis in the healthy body. The haemostatic system can be further defined as primary, secondary and tertiary haemostasis to better define the interdependent mechanisms that combine to maintain haemostasis. The term 'developmental haemostasis' was first introduced by Maureen Andrews in the 1980s to describe the age-related physiological changes of the coagulation system as it develops progressively over time from fetal, neonatal, paediatric to adult and geriatric systems. This paper will focus on developmental changes in secondary haemostasis, that is, the plasma protein changes that occur with age, particularly during the fetal and neonatal period, when the changes are most marked compared to the adult system.

  2. Understanding mineral dusts from the Middle East

    NASA Astrophysics Data System (ADS)

    Engelbrecht, J. P.; McDonald, E.; Gillies, J. A.; Jayanty, J.; Casuccio, G.; Gertler, A.

    2012-12-01

    The purpose of the program was to provide scientifically founded information on the chemical and physical properties of airborne mineral dust collected during a period of approximately one year, largely in 2006, at Djibouti, Afghanistan (Bagram, Khowst), Qatar, United Arab Emirates, Iraq (Balad, Baghdad, Tallil, Tikrit, Taji, Al Asad), and Kuwait (Northern, Central, Coastal, and Southern regions). To fully understand mineral dusts, their chemical and physical properties as well as mineralogical interrelationships were accurately established. Three collocated low volume particulate samplers, one each for the total suspended (TSP), less than 10 μm in aerodynamic diameter (PM10), and less than 2.5 μm in aerodynamic diameter (PM2.5) particulate matter were deployed at each of the 15 sites, operating on a "1 in 6 day" sampling schedule. A total of 3,136 filter samples were collected on a 1-in-6 day schedule, along with one-time bulk soil samples, at each of the 15 sites. Sample media included Teflon® membrane and quartz fiber filters for chemical analysis (71 species), and Nuclepore® filters for individual particle analysis by Scanning Electron Microscopy (SEM). The provisional study of the data revealed three broad air pollution sources: geological dust, smoke from burn pits, and until now unidentified lead-zinc smelters and battery-processing facilities. SEM results and secondary electron imagery show that quartz and other silicate minerals and, to a lesser extent, dolomite and calcite particles are coated by a thin Si-Al-Mg layer, probably the clay minerals palygorskite and/or montmorillonite/illite. Positive Matrix Factorization (PMF) was performed on aerosol samples collected at six military sites in Iraq (Balad, Baghdad, Tallil, Tikrit, Taji, and Al Asad). PMF results reflect chemical differences amongst sources impacting at individual sites, further complicated by the regional geomorphology and meteorology. Sampling sites are seldom impacted by one source at

  3. SECONDARY ELECTRON MULTIPLIERS

    DOEpatents

    Morton, G.A.; Green, M.W.

    1959-01-01

    A secondary emission multiplier having exceptionally high output signal current is described. In previous multiplier tubes the output signal current was limited by the space charge surrounding the electrodes. The present multiplier tubes provides a source of ions within the tube adjacent the anode to neutralize the space charge effect, and the dynode voltage is switched on intermittently for periods of time so brief that the ions do not move towards the cathode.

  4. Raynaud's phenomenon (secondary)

    PubMed Central

    2014-01-01

    Introduction Raynaud’s phenomenon is episodic vasospasm of the peripheral vessels. It presents as episodic colour changes of the digits (sometimes accompanied by pain and paraesthesia), usually in response to cold exposure or stress. The classic triphasic colour change is white (ischaemia), then blue (de-oxygenation), then red (reperfusion). Raynaud’s phenomenon can be primary (idiopathic) or secondary to several different conditions and causes. When secondary (e.g., to systemic sclerosis), it can progress to ulceration of the fingers and toes. This review deals with secondary Raynaud’s phenomenon. Methods and outcomes We conducted a systematic review and aimed to answer the following clinical questions: What are the effects of surgical interventions in complicated secondary Raynaud’s phenomenon? We searched: Medline, Embase, The Cochrane Library, and other important databases up to March 2014 (Clinical Evidence reviews are updated periodically; please check our website for the most up-to-date version of this review). We included harms alerts from relevant organisations such as the US Food and Drug Administration (FDA) and the UK Medicines and Healthcare products Regulatory Agency (MHRA). Results We found two studies that met our inclusion criteria. We performed a GRADE evaluation of the quality of evidence for interventions. Conclusions In this systematic review, we present information relating to the effectiveness and safety of the following interventions: botulinum toxin, simple debridement/surgical toilet of ulcers, peripheral sympathectomy (digital, digital plus sympathectomy of the ulnar and/or radial artery, ligation of the ulnar artery), cervical/thoracic sympathectomy, arterial reconstruction (venous graft, arterial graft, balloon angioplasty), and amputation PMID:25322727

  5. [Functional secondary megaduodenum].

    PubMed

    Vasile, I; Vilcea, D; Mogoş, D; Teodorescu, M; Păun, I; Iacob, T; Marinescu, Sidonia; Dragomir, T; Florescu, M

    2003-01-01

    This paper aim is to present the case of a 72 year old male, diagnosed with functional secondary megaduodenum. We intend to discuss the pathogenic and positive diagnostic difficulties (the presence or absence of a mechanical obstructive factor or the participated of the megaduodenum in an intestinal pseudo-obstruction syndrome). Also we outline the rare frequency of this disease and especially the therapeutic difficulties: inefficiency of conservatory treatment, delicate problems of surgical tactics and technique.

  6. 1996 annual report on Alaska's mineral resources

    USGS Publications Warehouse

    Schneider, Jill L.

    1997-01-01

    This is the fifteenth annual report that has been prepared in response to the Alaska National Interest Lands Conservation Act. Current Alaskan mineral projects and events that occurred during 1995 are summarized. For the purpose of this document, the term 'minerals' encompasses both energy resources (oil and gas, coal and peat, uranium, and geothermal) and nonfuel-mineral resources (metallic and industrial minerals).

  7. 43 CFR 8.5 - Mineral rights.

    Code of Federal Regulations, 2012 CFR

    2012-10-01

    ... 43 Public Lands: Interior 1 2012-10-01 2011-10-01 true Mineral rights. 8.5 Section 8.5 Public... INTERIOR AND OF THE ARMY RELATIVE TO RESERVOIR PROJECT LANDS § 8.5 Mineral rights. Mineral, oil and gas..., but mineral rights not acquired will be subordinated to the Government's right to regulate...

  8. 43 CFR 3861.3 - Mineral surveyors.

    Code of Federal Regulations, 2013 CFR

    2013-10-01

    ... 43 Public Lands: Interior 2 2013-10-01 2013-10-01 false Mineral surveyors. 3861.3 Section 3861.3..., DEPARTMENT OF THE INTERIOR MINERALS MANAGEMENT (3000) MINERAL PATENT APPLICATIONS Surveys and Plats § 3861.3 Mineral surveyors....

  9. 21 CFR 573.680 - Mineral oil.

    Code of Federal Regulations, 2013 CFR

    2013-04-01

    ... 21 Food and Drugs 6 2013-04-01 2013-04-01 false Mineral oil. 573.680 Section 573.680 Food and... Listing § 573.680 Mineral oil. Mineral oil may be safely used in animal feed, subject to the provisions of this section. (a) Mineral oil, for the purpose of this section, is that complying with the...

  10. 43 CFR 3830.10 - Locatable minerals.

    Code of Federal Regulations, 2011 CFR

    2011-10-01

    ... 43 Public Lands: Interior 2 2011-10-01 2011-10-01 false Locatable minerals. 3830.10 Section 3830..., DEPARTMENT OF THE INTERIOR MINERALS MANAGEMENT (3000) LOCATING, RECORDING, AND MAINTAINING MINING CLAIMS OR SITES; GENERAL PROVISIONS Mining Law Minerals § 3830.10 Locatable minerals....

  11. 43 CFR 3830.10 - Locatable minerals.

    Code of Federal Regulations, 2012 CFR

    2012-10-01

    ... 43 Public Lands: Interior 2 2012-10-01 2012-10-01 false Locatable minerals. 3830.10 Section 3830..., DEPARTMENT OF THE INTERIOR MINERALS MANAGEMENT (3000) LOCATING, RECORDING, AND MAINTAINING MINING CLAIMS OR SITES; GENERAL PROVISIONS Mining Law Minerals § 3830.10 Locatable minerals....

  12. 43 CFR 3861.3 - Mineral surveyors.

    Code of Federal Regulations, 2011 CFR

    2011-10-01

    ... 43 Public Lands: Interior 2 2011-10-01 2011-10-01 false Mineral surveyors. 3861.3 Section 3861.3..., DEPARTMENT OF THE INTERIOR MINERALS MANAGEMENT (3000) MINERAL PATENT APPLICATIONS Surveys and Plats § 3861.3 Mineral surveyors....

  13. 21 CFR 573.680 - Mineral oil.

    Code of Federal Regulations, 2011 CFR

    2011-04-01

    ... 21 Food and Drugs 6 2011-04-01 2011-04-01 false Mineral oil. 573.680 Section 573.680 Food and... Listing § 573.680 Mineral oil. Mineral oil may be safely used in animal feed, subject to the provisions of this section. (a) Mineral oil, for the purpose of this section, is that complying with the...

  14. 43 CFR 8.5 - Mineral rights.

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ... 43 Public Lands: Interior 1 2010-10-01 2010-10-01 false Mineral rights. 8.5 Section 8.5 Public... INTERIOR AND OF THE ARMY RELATIVE TO RESERVOIR PROJECT LANDS § 8.5 Mineral rights. Mineral, oil and gas..., but mineral rights not acquired will be subordinated to the Government's right to regulate...

  15. 43 CFR 8.5 - Mineral rights.

    Code of Federal Regulations, 2011 CFR

    2011-10-01

    ... 43 Public Lands: Interior 1 2011-10-01 2011-10-01 false Mineral rights. 8.5 Section 8.5 Public... INTERIOR AND OF THE ARMY RELATIVE TO RESERVOIR PROJECT LANDS § 8.5 Mineral rights. Mineral, oil and gas..., but mineral rights not acquired will be subordinated to the Government's right to regulate...

  16. 43 CFR 3861.3 - Mineral surveyors.

    Code of Federal Regulations, 2012 CFR

    2012-10-01

    ... 43 Public Lands: Interior 2 2012-10-01 2012-10-01 false Mineral surveyors. 3861.3 Section 3861.3..., DEPARTMENT OF THE INTERIOR MINERALS MANAGEMENT (3000) MINERAL PATENT APPLICATIONS Surveys and Plats § 3861.3 Mineral surveyors....

  17. 43 CFR 3830.10 - Locatable minerals.

    Code of Federal Regulations, 2013 CFR

    2013-10-01

    ... 43 Public Lands: Interior 2 2013-10-01 2013-10-01 false Locatable minerals. 3830.10 Section 3830..., DEPARTMENT OF THE INTERIOR MINERALS MANAGEMENT (3000) LOCATING, RECORDING, AND MAINTAINING MINING CLAIMS OR SITES; GENERAL PROVISIONS Mining Law Minerals § 3830.10 Locatable minerals....

  18. 43 CFR 8.5 - Mineral rights.

    Code of Federal Regulations, 2013 CFR

    2013-10-01

    ... 43 Public Lands: Interior 1 2013-10-01 2013-10-01 false Mineral rights. 8.5 Section 8.5 Public... INTERIOR AND OF THE ARMY RELATIVE TO RESERVOIR PROJECT LANDS § 8.5 Mineral rights. Mineral, oil and gas..., but mineral rights not acquired will be subordinated to the Government's right to regulate...

  19. 21 CFR 573.680 - Mineral oil.

    Code of Federal Regulations, 2014 CFR

    2014-04-01

    ... 21 Food and Drugs 6 2014-04-01 2014-04-01 false Mineral oil. 573.680 Section 573.680 Food and... Listing § 573.680 Mineral oil. Mineral oil may be safely used in animal feed, subject to the provisions of this section. (a) Mineral oil, for the purpose of this section, is that complying with the...

  20. 21 CFR 573.680 - Mineral oil.

    Code of Federal Regulations, 2012 CFR

    2012-04-01

    ... 21 Food and Drugs 6 2012-04-01 2012-04-01 false Mineral oil. 573.680 Section 573.680 Food and... Listing § 573.680 Mineral oil. Mineral oil may be safely used in animal feed, subject to the provisions of this section. (a) Mineral oil, for the purpose of this section, is that complying with the...

  1. 43 CFR 3861.3 - Mineral surveyors.

    Code of Federal Regulations, 2014 CFR

    2014-10-01

    ... 43 Public Lands: Interior 2 2014-10-01 2014-10-01 false Mineral surveyors. 3861.3 Section 3861.3..., DEPARTMENT OF THE INTERIOR MINERALS MANAGEMENT (3000) MINERAL PATENT APPLICATIONS Surveys and Plats § 3861.3 Mineral surveyors....

  2. 43 CFR 8.5 - Mineral rights.

    Code of Federal Regulations, 2014 CFR

    2014-10-01

    ... 43 Public Lands: Interior 1 2014-10-01 2014-10-01 false Mineral rights. 8.5 Section 8.5 Public... INTERIOR AND OF THE ARMY RELATIVE TO RESERVOIR PROJECT LANDS § 8.5 Mineral rights. Mineral, oil and gas..., but mineral rights not acquired will be subordinated to the Government's right to regulate...

  3. 43 CFR 3830.10 - Locatable minerals.

    Code of Federal Regulations, 2014 CFR

    2014-10-01

    ... 43 Public Lands: Interior 2 2014-10-01 2014-10-01 false Locatable minerals. 3830.10 Section 3830..., DEPARTMENT OF THE INTERIOR MINERALS MANAGEMENT (3000) LOCATING, RECORDING, AND MAINTAINING MINING CLAIMS OR SITES; GENERAL PROVISIONS Mining Law Minerals § 3830.10 Locatable minerals....

  4. 21 CFR 573.680 - Mineral oil.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ... 21 Food and Drugs 6 2010-04-01 2010-04-01 false Mineral oil. 573.680 Section 573.680 Food and... Listing § 573.680 Mineral oil. Mineral oil may be safely used in animal feed, subject to the provisions of this section. (a) Mineral oil, for the purpose of this section, is that complying with the...

  5. Portable Radiometer Identifies Minerals in the Field

    NASA Technical Reports Server (NTRS)

    Goetz, A. F. H.; Machida, R. A.

    1982-01-01

    Hand-held optical instrument aids in identifying minerals in field. Can be used in exploration for minerals on foot or by aircraft. The radiometer is especially suitable for identifying clay and carbonate minerals. Radiometer measures reflectances of mineral at two wavelengths, computes ratio of reflectances, and displays ratio to user.

  6. Formation and Reactivity of Biogenic Iron Minerals

    SciTech Connect

    Ferris, F. Grant

    2002-06-01

    Dissimilatory iron-reducing bacteria (DIRB) play an important role in regulating the aqueous geochemistry of iron and other metals in anaerobic, non-sulfidogenic groundwater environments; however, little work has directly assessed the cell surface electrochemistry of DIRB, or the nature of the interfacial environment around individual cells. The electrochemical properties of particulate solids are often inferred from titrations in which net surface charge is determined, assuming electroneutrality, as the difference between known added amounts of acid and base and measured proton concentration. The resultant titration curve can then be fit to a speciation model for the system to determine pKa values and site densities of reactive surface sites. Moreover, with the development of non-contact electrostatic force microscopy (EFM), it is now possible to directly inspect and quantify charge development on surfaces. A combination of acid-base titrations and EFM are being used to assess the electrochemical surface properties of the groundwater DIRB, Shewanella putrefaciens. The pKa spectra and EFM data show together that a high degree of electrochemical heterogeneity exists within the cell wall and at the cell surface of S. putrefaciens. Recognition of variations in the nature and spatial distribution of reactive sites that contribute to charge development on these bacteria implies further that the cell surface of these Fe(III)-reducing bacteria functions as a highly differentiated interfacial system capable of supporting multiple intermolecular interactions with both solutes and solids. These include surface complexation reactions involving dissolved metals, as well as adherence to mineral substrates such as hydrous ferric oxide through longer-range electrostatic interactions, and surface precipitation of secondary reduced-iron minerals.

  7. Traditional Methods for Mineral Analysis

    NASA Astrophysics Data System (ADS)

    Ward, Robert E.; Carpenter, Charles E.

    This chapter describes traditional methods for analysis of minerals involving titrimetric and colorimetric procedures, and the use of ion selective electrodes. Other traditional methods of mineral analysis include gravimetric titration (i.e., insoluble forms of minerals are precipitated, rinse, dried, and weighed) and redox reactions (i.e., mineral is part of an oxidation-reduction reaction, and product is quantitated). However, these latter two methods will not be covered because they currently are used little in the food industry. The traditional methods that will be described have maintained widespread usage in the food industry despite the development of more modern instrumentation such as atomic absorption spectroscopy and inductively coupled plasma-atomic emission spectroscopy (Chap. 24). Traditional methods generally require chemicals and equipment that are routinely available in an analytical laboratory and are within the experience of most laboratory technicians. Additionally, traditional methods often form the basis for rapid analysis kits (e.g., Quantab®; for salt determination) that are increasingly in demand. Procedures for analysis of minerals of major nutritional or food processing concern are used for illustrative purposes. For additional examples of traditional methods refer to references (1-6). Slight modifications of these traditional methods are often needed for specific foodstuffs to minimize interferences or to be in the range of analytical performance. For analytical requirements for specific foods see the Official Methods of Analysis of AOAC International (5) and related official methods (6).

  8. 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.

  9. The pleiotropic effects of paricalcitol: Beyond bone-mineral metabolism.

    PubMed

    Egido, Jesús; Martínez-Castelao, Alberto; Bover, Jordi; Praga, Manuel; Torregrosa, José Vicente; Fernández-Giráldez, Elvira; Solozábal, Carlos

    2016-01-01

    Secondary hyperparathyroidism (SHPT) is a common complication in patients with chronic kidney disease (CKD) that is characterised by elevated parathyroid hormone (PTH) levels and a series of bone-mineral metabolism anomalies. In patients with SHPT, treatment with paricalcitol, a selective vitamin D receptor activator, has been shown to reduce PTH levels with minimal serum calcium and phosphorus variations. The classic effect of paricalcitol is that of a mediator in mineral and bone homeostasis. However, recent studies have suggested that the benefits of treatment with paricalcitol go beyond PTH reduction and, for instance, it has a positive effect on cardiovascular disease and survival. The objective of this study is to review the most significant studies on the so-called pleiotropic effects of paricalcitol treatment in patients with CKD. PMID:26705959

  10. The pleiotropic effects of paricalcitol: Beyond bone-mineral metabolism.

    PubMed

    Egido, Jesús; Martínez-Castelao, Alberto; Bover, Jordi; Praga, Manuel; Torregrosa, José Vicente; Fernández-Giráldez, Elvira; Solozábal, Carlos

    2016-01-01

    Secondary hyperparathyroidism (SHPT) is a common complication in patients with chronic kidney disease (CKD) that is characterised by elevated parathyroid hormone (PTH) levels and a series of bone-mineral metabolism anomalies. In patients with SHPT, treatment with paricalcitol, a selective vitamin D receptor activator, has been shown to reduce PTH levels with minimal serum calcium and phosphorus variations. The classic effect of paricalcitol is that of a mediator in mineral and bone homeostasis. However, recent studies have suggested that the benefits of treatment with paricalcitol go beyond PTH reduction and, for instance, it has a positive effect on cardiovascular disease and survival. The objective of this study is to review the most significant studies on the so-called pleiotropic effects of paricalcitol treatment in patients with CKD.

  11. Rock Magnetic Mineral Assemblage in Mineral Separates from Xenoliths of Continental Lithospheric Mantle

    NASA Astrophysics Data System (ADS)

    Khakhalova, E.; Feinberg, J. M.; Ionov, D. A.; Ferre, E. C.; Friedman, S. A.; Hernandez, F. M.; Neal, C. R.; Conder, J. A.

    2014-12-01

    Studies of aeromagnetic anomalies suggest that the lithospheric mantle may contribute to long wavelength features. Examination of unaltered mantle xenoliths may reveal the mineralogical sources of these aeromagnetic anomalies. Prior work has reported microscopic inclusions of magnetic minerals in mantle silicates. Here we explore the magnetism of pure olivine, clinopyroxene, orthopyroxene, and spinel separated from peridotite xenoliths from the Dariganga and Tariat localities in Mongolia that sample the lithospheric mantle. All separates were leached with HF and HCl to remove secondary minerals adhering to the surface of the grains or in cracks. Separates were then mounted in cement to create monomineralic specimens for investigation using hysteresis loops, first order reversal curves (FORC), alternating field and thermal demagnetization of a 1T IRM, and low-temperature magnetometry. All specimens showed trace concentrations of ferromagnetic inclusions with Ms values of ~10-3 Am2kg-1. Thermal demagnetization showed a range of unblocking temperatures with median destructive temperatures of 300-400°C. Two specimens showed a dramatic demagnetization at 585°C, consistent with pure magnetite (Mt). The presence of Mt was confirmed by observations of the Verwey transition at 100-120K and by backfield remanence acquisition curves that plateau at ~300 mT. The median destructive alternating field was ~20 mT and 40-80 mT for specimens from Dariganga and Tariat, respectively. FORC diagrams show single-domain-like behavior with a median Hc of ~20 mT. The demagnetization experiments suggest that Mt inclusions in the lattice of olivine, opx, cpx and spinel carry magnetic remanence. Thus, the lithospheric mantle may exhibit in-situ ferromagnetism carried by Mt below 585°C. The magnetization of separates varies between xenolith localities but is consistent amongst minerals of the same locality. Future work will address whether the Mt formed before or during xenolith ascent.

  12. Cellular compartmentalization of secondary metabolism

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Fungal secondary metabolism is often considered apart from the essential housekeeping functions of the cell. However, there are clear links between fundamental cellular metabolism and the biochemical pathways leading to secondary metabolite synthesis. Besides utilizing key biochemical precursors sh...

  13. Radioactivity in bottled mineral waters.

    PubMed

    Martín Sánchez, A; Rubio Montero, M P; Gómez Escobar, V; Jurado Vargas, M

    1999-06-01

    Consumption of bottled mineral water is a growing practice and is sometimes a necessity rather than a choice. In this work, a study of the radioactive content of a wide selection of commercial bottled mineral waters for human intake was carried out. The origins of the analyzed waters were very different, coming from various locations in France, Portugal and Spain. Their total alpha and beta activity concentrations were determined and also gamma spectrometry was used to detect some radionuclides. In some cases, the waters presented high values of the total alpha and beta activity concentrations surpassing the reference levels established by the CSN, the Spanish. Regulatory Organization. In these cases, a determination of uranium and 226Ra was also performed by using low-level liquid scintillation counting. The results revealed a strong correlation between radioactive content and dry residue, and lead one to conclude that high radioactive content is mainly related to the mineralization in waters of underground origin.

  14. Respiratory disability in coal miners

    SciTech Connect

    Morgan, W.K.C.; Lapp, N.L.; Seaton, D.

    1980-06-20

    It has been suggested that the assessment of ventilatory capacity alone is inadequate for the determination of disabling occupational respiratory impairment in coal miners. The Department of Labor has accepted this view and now routinely requests blood gas analyses in those claimants not meeting the ventilatory criteria. We tested the validity of this contention by selecting two groups of coal miners claiming total disability. The first consisted of 150 claimants who were referred for spirometry, while the second consisted of 50 claimants who had been referred for blood gas studies. Of those in group 1, eight met the extant criteria for disability, while only two of those in group 2 satisfied the criteria, and, in both, cardiac disease was responsible. We conclude that blood gas analyses are unnecessary in the determination of pulmonary disability in coal miners.

  15. Mineral Abundance Near Aristarchus Crater

    NASA Astrophysics Data System (ADS)

    Bradford, Alison; Storrs, A.

    2007-12-01

    Mineral Abundance Near Aristarchus Crater Alison Bradford and Alex Storrs Towson University We analyze Hubble Space Telescope (HST) images to determine the abundance of minerals near Aristarchus crater. Following the calibration of Robinson et al. (2007) we present ratio maps of images obtained in August of 2005 showing the abundance of TiO2 and other minerals in this interesting area in the middle of Oceanus Procellarum. A prominent cleft (Schroter's Valley, presumably a collapsed lava tube) makes this region of special interest for analyzing the formation of mare basalts. Reference: Robinson, M.S., et al. (2007): "High resolution mapping of TiO2 abundances on the Moon using the Hubble Space Telescope", GRL 34, L13203

  16. Geochemistry and Minerality of Wine

    NASA Astrophysics Data System (ADS)

    Oze, C.; Horton, T. W.; Beaman, M.

    2010-12-01

    Kaolinite (Al2Si2O5(OH)4) and gibbsite (Al(OH)3) are capable of forming in a variety of environments including anthropogenic solutions such as wine. Here, we evaluate the geochemistry of twelve white wines in order to assess the potential relationship between kaolinite/gibbsite saturation and minerality, a common wine descriptor used to express the rock and/or soil character in the aromas and flavors of wines. Aluminum and Si concentrations ranged from 228-1,281 µg L-1 and 6,583-19,746 µg L-1, respectively, where Si and Al are the only elements to demonstrate positive covariance with minerality scores. Sulfur levels varied from 25,013-167,383 µg L-1 and show the strongest negative covariance with minerality scores. However, like all of the elements studied (Al, Si, Na, Mg, S, K, Ca, and Fe), these trends were not significantly different than random at the 95% confidence level. In contrast, the relative degrees of gibbsite/kaolinite saturation display strong positive covariance with minerality scores and these trends are not random at the greater than 95% confidence level. Overall, our tasters were able to accurately assess the degree of gibbsite/kaolinite saturation amongst the twelve wines based on the objective of assessing minerality. Although the wines were undersaturated with respect to gibbsite/kaolinite, geochemical modeling reveals that increasing the wines’ pHs from ~3.3 to 4.1-4.6 (which is achievable on the palate where saliva has a pH of 7.4) results in gibbsite/kaolinite oversaturation. By considering that minerality is a function of gibbsite/kaolinite saturation and decreasing S, the origin of minerality’s taste and chemical origin in wine with known physical standards becomes increasingly crystalline.

  17. Nucleoside phosphorylation by phosphate minerals.

    PubMed

    Costanzo, Giovanna; Saladino, Raffaele; Crestini, Claudia; Ciciriello, Fabiana; Di Mauro, Ernesto

    2007-06-01

    In the presence of formamide, crystal phosphate minerals may act as phosphate donors to nucleosides, yielding both 5'- and, to a lesser extent, 3'-phosphorylated forms. With the mineral Libethenite the formation of 5'-AMP can be as high as 6% of the adenosine input and last for at least 10(3) h. At high concentrations, soluble non-mineral phosphate donors (KH(2)PO(4) or 5'-CMP) afford 2'- and 2':3'-cyclic AMP in addition to 5'-and 3'-AMP. The phosphate minerals analyzed were Herderite Ca[BePO(4)F], Hureaulite Mn(2+)(5)(PO(3)(OH)(2)(PO(4))(2)(H(2)O)(4), Libethenite Cu(2+)(2)(PO(4))(OH), Pyromorphite Pb(5)(PO(4))(3)Cl, Turquoise Cu(2+)Al(6)(PO(4))(4)(OH)(8)(H(2)O)(4), Fluorapatite Ca(5)(PO(4))(3)F, Hydroxylapatite Ca(5)(PO(4))(3)OH, Vivianite Fe(2+)(3)(PO(4))(2)(H(2)O)(8), Cornetite Cu(2+)(3)(PO(4))(OH)(3), Pseudomalachite Cu(2+)(5)(PO(4))(2)(OH)(4), Reichenbachite Cu(2+)(5)(PO(4))(2)(OH)(4), and Ludjibaite Cu(2+)(5)(PO(4))(2)(OH)(4)). Based on their behavior in the formamide-driven nucleoside phosphorylation reaction, these minerals can be characterized as: 1) inactive, 2) low level phosphorylating agents, or 3) active phosphorylating agents. Instances were detected (Libethenite and Hydroxylapatite) in which phosphorylation occurs on the mineral surface, followed by release of the phosphorylated compounds. Libethenite and Cornetite markedly protect the beta-glycosidic bond. Thus, activated nucleic monomers can form in a liquid non-aqueous environment in conditions compatible with the thermodynamics of polymerization, providing a solution to the standard-state Gibbs free energy change (DeltaG degrees ') problem, the major obstacle for polymerizations in the liquid phase in plausible prebiotic scenarios.

  18. Mineral Supertrumps: A new card game to assist learning of mineralogy

    NASA Astrophysics Data System (ADS)

    Spandler, C.

    2015-12-01

    Mineralogy is considered one of the cornerstone subjects of geoscience curriculum. It provides the basic information from which we can understand the composition and behaviour of Earth and planetary materials, yet many students struggle to obtain adequate comprehension and knowledge of mineralogy during tertiary degree programs. Here, I introduce a new card game called "Mineral Supertrumps" that can be used to assist teaching of mineralogy at secondary and tertiary level. The card game is easy to learn and play, and is designed to promote active learning in a group environment. The game involves 3 to 6 people, and is similar to the "Top Trumps™" card games. The pack consists of 54 mineral cards, and 6 supertrump cards. Each mineral card includes information about the mineral such as the generic chemical formula, the classification, crystal system, the geological environment where the mineral is commonly found or formed, as well as information in the five playing categories (or trumps) of Hardness, Specific Gravity, Cleavage, Crustal Abundance, and Economic Value. The first three playing categories relate to distinct physical properties of the mineral, while last two categories rate the importance of the mineral in terms of abundance in the Earth's crust and value to modern societies. Results of a formal evaluation of the game by students in the second year of a tertiary geology program indicate that the game has clear benefits for learning about mineralogy. The majority of students enjoyed playing the game and considered it to be effective for enhancing learning about mineral properties and their application to other Earth Science disciplines. Therefore, inclusion of "Mineral Supertrumps" into Earth Science curriculum at secondary or tertiary level has the potential to redress the difficulties students face in learning of mineralogy, while requiring little to no adjustment to existing teaching programs.

  19. Accelerated Growth Plate Mineralization and Foreshortened Proximal Limb Bones in Fetuin-A Knockout Mice

    PubMed Central

    Gupta, Himadri S.; Schäfer, Cora; Krauss, Stefanie; Dunlop, John W. C.; Masic, Admir; Kerschnitzki, Michael; Zaslansky, Paul; Boesecke, Peter; Catalá-Lehnen, Philip; Schinke, Thorsten; Fratzl, Peter; Jahnen-Dechent, Willi

    2012-01-01

    The plasma protein fetuin-A/alpha2-HS-glycoprotein (genetic symbol Ahsg) is a systemic inhibitor of extraskeletal mineralization, which is best underscored by the excessive mineral deposition found in various tissues of fetuin-A deficient mice on the calcification-prone genetic background DBA/2. Fetuin-A is known to accumulate in the bone matrix thus an effect of fetuin-A on skeletal mineralization is expected. We examined the bones of fetuin-A deficient mice maintained on a C57BL/6 genetic background to avoid bone disease secondary to renal calcification. Here, we show that fetuin-A deficient mice display normal trabecular bone mass in the spine, but increased cortical thickness in the femur. Bone material properties, as well as mineral and collagen characteristics of cortical bone were unaffected by the absence of fetuin-A. In contrast, the long bones especially proximal limb bones were severely stunted in fetuin-A deficient mice compared to wildtype littermates, resulting in increased biomechanical stability of fetuin-A deficient femora in three-point-bending tests. Elevated backscattered electron signal intensities reflected an increased mineral content in the growth plates of fetuin-A deficient long bones, corroborating its physiological role as an inhibitor of excessive mineralization in the growth plate cartilage matrix - a site of vigorous physiological mineralization. We show that in the case of fetuin-A deficiency, active mineralization inhibition is a necessity for proper long bone growth. PMID:23091616

  20. Accelerated growth plate mineralization and foreshortened proximal limb bones in fetuin-A knockout mice.

    PubMed

    Seto, Jong; Busse, Björn; Gupta, Himadri S; Schäfer, Cora; Krauss, Stefanie; Dunlop, John W C; Masic, Admir; Kerschnitzki, Michael; Zaslansky, Paul; Boesecke, Peter; Catalá-Lehnen, Philip; Schinke, Thorsten; Fratzl, Peter; Jahnen-Dechent, Willi

    2012-01-01

    The plasma protein fetuin-A/alpha2-HS-glycoprotein (genetic symbol Ahsg) is a systemic inhibitor of extraskeletal mineralization, which is best underscored by the excessive mineral deposition found in various tissues of fetuin-A deficient mice on the calcification-prone genetic background DBA/2. Fetuin-A is known to accumulate in the bone matrix thus an effect of fetuin-A on skeletal mineralization is expected. We examined the bones of fetuin-A deficient mice maintained on a C57BL/6 genetic background to avoid bone disease secondary to renal calcification. Here, we show that fetuin-A deficient mice display normal trabecular bone mass in the spine, but increased cortical thickness in the femur. Bone material properties, as well as mineral and collagen characteristics of cortical bone were unaffected by the absence of fetuin-A. In contrast, the long bones especially proximal limb bones were severely stunted in fetuin-A deficient mice compared to wildtype littermates, resulting in increased biomechanical stability of fetuin-A deficient femora in three-point-bending tests. Elevated backscattered electron signal intensities reflected an increased mineral content in the growth plates of fetuin-A deficient long bones, corroborating its physiological role as an inhibitor of excessive mineralization in the growth plate cartilage matrix--a site of vigorous physiological mineralization. We show that in the case of fetuin-A deficiency, active mineralization inhibition is a necessity for proper long bone growth.

  1. Water concentrations in mantle peridotite minerals

    NASA Astrophysics Data System (ADS)

    Warren, J. M.; Hauri, E. H.

    2010-12-01

    The concentration and distribution of volatiles in the mantle is important for constraining many key properties, including melting systematics at ridges and subduction zones. We present measurements of water concentrations in nominally anhydrous minerals from abyssal, orogenic and xenolith peridotites. Analyses of fresh and altered samples from a variety of locations are used to assess the extent to which mineral water concentrations reflect primary mantle compositions, versus diffusive loss and/or hydration due to secondary processes. Water concentrations were measured in olivine (Ol), orthopyroxene (Opx) and clinopyroxene (Cpx) by ion microprobe, using mineral specific standards and monitoring background concentrations by analysis of synthetic forsterite. Analytical reproducibility, based on 11 repeat analyses of an Ol grain, is 10%, while background H2O levels varied from 7-19 ppm. Samples include xenoliths from Pali Aike, Samoa and Spitsbergen, along with unusually fresh oceanic peridotites from the Gakkel Ridge and the Tonga Trench. In addition, samples were analyzed from the Southwest Indian Ridge (SWIR) and the Josephine Peridotite, both of which have moderate degrees of alteration. In olivine, water concentrations are <11 ppm, with the exception of Pali Aike xenoliths, which have water concentrations of 16-33 ppm. On average, peridotite Opx have 187 ppm and Cpx have 474 ppm. Pyroxenite veins from the Southwest Indian Ridge have systematically lower concentrations, with an average of 12 ppm in Opx and 55 ppm in Cpx. Water partition coefficients for Opx/Ol have an average value of 28 and Cpx/Ol of 57, significantly higher than previous estimates (e.g., Hirth and Kohlstedt, 1996). Excluding the pyroxenites, the average Cpx/Opx partition coefficient is 2, in agreement with published estimates. This suggests that Cpx and Opx preserve mantle water concentrations, whereas Ol has undergone hydrogen loss. Mineral rims have water concentrations that are within error

  2. Modeling Hydrothermal Mineralization: Fractal or Multifrcatal Models?

    NASA Astrophysics Data System (ADS)

    Cheng, Q.

    2004-05-01

    Hydrothermal mineralization occurs when the natural geo-processes involve the interaction of ore material-carrying hydrothermal fluids with rocks in the earth's crust in a specific geological environment. Mineralization can cause element concentration enrichment or depletion in the country rocks. Local enrichment may form ore body that can be mined for profit at the current economic and technological conditions. To understand the spatial distribution of element concentration enrichment or depletion caused by mineralization in a mineral district is essential for mineral exploration and mineral prediction. Grade-tonnage model and mineral deposits size distribution model are common models used for characterizing mineral deposits. This paper proposes a non-linear mineralization model on the basis of a modified classical igneous differentiation mineralization model to describe the generation of multifractal distribution of element concentration in the country rocks as well as grade-tonnage fractal/multifractal distribution of ore deposits that have been often observed in hydrothermal mineralization. This work may also lead to a singularity model to explain the common properties of mineralization and mineralization-associated geochemical anomaly diversity and the generalized self-similarity of the anomalies. The model has been applied to a case study of mineral deposits prediction and mineral resource assessment in the Abitibi district, northern Ontario, Canada.

  3. Viewing minerals, atom by atom

    NASA Astrophysics Data System (ADS)

    Maggs, William Ward

    With state-of-the-art technology supported by scissors and bungy cords, Earth scientists are beginning to look at mineral surfaces and mineral-fluid interactions on an atomic scale.The instrument that can provide such a detailed view is the scanning tunneling microscope (STM), which made a great theoretical and practical splash when it was introduced in 1981 by Gerd Binnig and Heinrich Rohrer, physicists at IBM's laboratory in Zurich. They won a Nobel Prize in Physics for their work 5 years later.

  4. 43 CFR 3873.1 - Segregation of mineral from non-mineral land.

    Code of Federal Regulations, 2014 CFR

    2014-10-01

    ... 43 Public Lands: Interior 2 2014-10-01 2014-10-01 false Segregation of mineral from non-mineral...) BUREAU OF LAND MANAGEMENT, DEPARTMENT OF THE INTERIOR MINERALS MANAGEMENT (3000) ADVERSE CLAIMS, PROTESTS AND CONFLICTS Segregation § 3873.1 Segregation of mineral from non-mineral land. Where a survey...

  5. 43 CFR 3873.1 - Segregation of mineral from non-mineral land.

    Code of Federal Regulations, 2011 CFR

    2011-10-01

    ... 43 Public Lands: Interior 2 2011-10-01 2011-10-01 false Segregation of mineral from non-mineral...) BUREAU OF LAND MANAGEMENT, DEPARTMENT OF THE INTERIOR MINERALS MANAGEMENT (3000) ADVERSE CLAIMS, PROTESTS AND CONFLICTS Segregation § 3873.1 Segregation of mineral from non-mineral land. Where a survey...

  6. 43 CFR 3873.1 - Segregation of mineral from non-mineral land.

    Code of Federal Regulations, 2012 CFR

    2012-10-01

    ... 43 Public Lands: Interior 2 2012-10-01 2012-10-01 false Segregation of mineral from non-mineral...) BUREAU OF LAND MANAGEMENT, DEPARTMENT OF THE INTERIOR MINERALS MANAGEMENT (3000) ADVERSE CLAIMS, PROTESTS AND CONFLICTS Segregation § 3873.1 Segregation of mineral from non-mineral land. Where a survey...

  7. 43 CFR 3873.1 - Segregation of mineral from non-mineral land.

    Code of Federal Regulations, 2013 CFR

    2013-10-01

    ... 43 Public Lands: Interior 2 2013-10-01 2013-10-01 false Segregation of mineral from non-mineral...) BUREAU OF LAND MANAGEMENT, DEPARTMENT OF THE INTERIOR MINERALS MANAGEMENT (3000) ADVERSE CLAIMS, PROTESTS AND CONFLICTS Segregation § 3873.1 Segregation of mineral from non-mineral land. Where a survey...

  8. Is the geological concept of clay minerals appropriate for soil science? A literature-based and philosophical analysis

    NASA Astrophysics Data System (ADS)

    Churchman, G. Jock

    . Phyllosilicates from non-soil or geological sources are poor models for the representation of secondary clay-size minerals in soils. In philosophical terms, the reduction of soil mineralogy to mineralogy as it is practiced within geology is misleading because of the differences between the minerals formed in soil and geological environments. In other words, clay minerals as they are defined as mineralogical entities for geology are of a different ‘kind’ to clay minerals in soils and cannot serve as ‘types’ or ‘stereotypes’ to enable explanation of the contribution of secondary clay-size minerals to soil properties or behavior. It is more useful to view clay minerals in soils as secondary inorganic compounds of clay-size than to follow their definition for non-soil purposes as plastic phyllosilicate minerals.

  9. Fe-Ni metal and sulfide minerals in CM chondrites: An indicator for thermal history

    USGS Publications Warehouse

    Kimura, M.; Grossman, J.N.; Weisberg, M.K.

    2011-01-01

    CM chondrites were subjected to aqueous alteration and, in some cases, to secondary metamorphic heating. The effects of these processes vary widely, and have mainly been documented in silicate phases. Herein, we report the characteristic features of Fe-Ni metal and sulfide phases in 13 CM and 2 CM-related chondrites to explore the thermal history of these chondrites. The texture and compositional distribution of the metal in CM are different from those in unequilibrated ordinary and CO chondrites, but most have similarities to those in highly primitive chondrites, such as CH, CR, and Acfer 094. We classified the CM samples into three categories based on metal composition and sulfide texture. Fe-Ni metal in category A is kamacite to martensite. Category B is characterized by pyrrhotite grains always containing blebs or lamellae of pentlandite. Opaque mineral assemblages of category C are typically kamacite, Ni-Co-rich metal, and pyrrhotite. These categories are closely related to the degree of secondary heating and are not related to degree of the aqueous alteration. The characteristic features of the opaque minerals can be explained by secondary heating processes after aqueous alteration. Category A CM chondrites are unheated, whereas those in category B experienced small degrees of secondary heating. CMs in category C were subjected to the most severe secondary heating process. Thus, opaque minerals can provide constraints on the thermal history for CM chondrites. ?? The Meteoritical Society, 2011.

  10. Nonaqueous secondary batteries

    NASA Astrophysics Data System (ADS)

    Yamahira, Takayuki; Anzai, Masanori

    1991-04-01

    The object of the present invention is to make possible the repeated use for a long period of time of nonaqueous secondary battery that contains in the battery case a negative electrode of a carbonized organic substance, a positive electrode with Li(x)MO2 (where M is at least one of Co and Ni; x being 0.05 less than or = x less than or = 1.10) and an electrolytic solution. The method comprises at least one charging operation of the battery before the sealing of their cells to inhibit the gas generation that would occur in the finished battery in its charging and discharging.

  11. Detrital Mineral Grains in Tektites.

    PubMed

    Bairnes, V E

    1963-12-27

    Abundant detrital crystalline mineral grains have been found in layered Muong Nong-type indochinite tektites from Nong Sapong, northeastern Thailand. These grains are an integral part of some tektite layers, and their presence furnishes strong presumptive evidence that indochinites, as well as other tektite groups in which layered specimens occur, formed from surficial earth materials.

  12. Mineral evolution and Earth history

    USGS Publications Warehouse

    Bradley, Dwight C.

    2015-01-01

    The field of mineral evolution—a merger of mineralogy and Earth history—coalesced in 2008 with the first of several global syntheses by Robert Hazen and coworkers in the American Mineralogist. They showed that the cumulative abundance of mineral species has a stepwise trend with first appearances tied to various transitions in Earth history such as the end of planetary accretion at ca. 4.55 Ga and the onset of bio-mediated mineralogy at ca. >2.5 Ga. A global age distribution is best established for zircon. Observed abundance of zircon fluctuates through more than an order of magnitude during successive supercontinent cycles. The pulse of the Earth is also recorded, albeit imperfectly, by the 87Sr/86Sr composition of marine biogenic calcite; the Sr-isotopic ratio of this mineral reflects the balance of inputs of primitive strontium at mid-ocean ridges and evolved strontium that drains off the continents. A global mineral evolution database, currently in the works, will greatly facilitate the compilation and analysis of extant data and the expansion of research in mineralogy outside its traditional bounds and into more interdisciplinary realms.

  13. Mineral of the month: boron

    USGS Publications Warehouse

    Lyday, Phyllis A.

    2005-01-01

    What does boron have to do with baseball, apple pie, motherhood and Chevrolet? Boron minerals and chemicals are used in the tanning of leather baseballs and gloves; in micro-fertilizer to grow apples and in the glass and enamels of bakewares to cook apple pie; in boron detergents for soaking baby clothes and diapers; and in fiberglass parts for the Chevrolet Corvette.

  14. Mineral of the month: indium

    USGS Publications Warehouse

    George, Micheal W.

    2004-01-01

    Indium was discovered in Germany in 1863. Although it is a lustrous silver-white color, the finders named the new material for the “indigo” spectral lines the mineral created on the spectrograph. Indium ranks 61st in abundance in Earth’s crust and is about three times more abundant than silver or mercury.

  15. Mineral impurities in coal combustion

    SciTech Connect

    Raask, E.

    1985-01-01

    This article discusses the many and varied problems associated with coal combustion and suggests remedial measures to assist in producing electrical energy from coal more efficiently. Contents include: influence of coal mineral matter on boiler design; mineral impurities in coal; quality of coal utilized in power stations; coal grinding, abrasive fuel minerals and plant wear; particulates silicate minerals in boiler flame; reactions of nonsilicate impurities in coal flame; creation, capture and coalescence of particulate ash in boiler flame; slag viscosity; sintering, fusion and slagging propensities of coal ashes, adhesion of ash deposit on boiler tubes and refractory materials; deposition mechanisms, rate measurements and the mode of formation of boiler deposits; thermal radiation and heat transfer properties of boiler deposits; measures to combat boiler fouling and slagging; some specific ash-related problems with US Coals; use of additives in coal fired boilers; high temperature corrosion in coal-fired plants; ash impaction erosion wear; low temeprature fouling and corrosion; comparison of ash-related problems in pulverized fuel and other coal-fired systems.

  16. Mineral of the month: titanium

    USGS Publications Warehouse

    Gambogi, Joseph

    2004-01-01

    From paint to airplanes, titanium is important in a number of applications. Commercial production comes from titanium-bearing ilmenite, rutile and leucoxene (altered ilmenite). These minerals are used to produce titanium dioxide pigment, as well as an assortment of metal and chemical products.

  17. Mineral of the month: aggregates

    USGS Publications Warehouse

    Tepordei, Valentin V.

    2005-01-01

    Natural aggregates, consisting of crushed stone, and sand and gravel, are a major contributor to economic health, and have an amazing variety of uses. Aggregates are among the most abundant mineral resources and are major basic raw materials used by construction, agriculture and other industries that employ complex chemical and metallurgical processes.

  18. Detrital Mineral Grains in Tektites.

    PubMed

    Bairnes, V E

    1963-12-27

    Abundant detrital crystalline mineral grains have been found in layered Muong Nong-type indochinite tektites from Nong Sapong, northeastern Thailand. These grains are an integral part of some tektite layers, and their presence furnishes strong presumptive evidence that indochinites, as well as other tektite groups in which layered specimens occur, formed from surficial earth materials. PMID:17834370

  19. Mineral of the month: rhenium

    USGS Publications Warehouse

    Magyar, Michael J.

    2005-01-01

    Rhenium, an exotic, heat-resistant metal, has grown in importance since its discovery nearly 80 years ago. First isolated by a team of German chemists studying a platinum ore, the mineral was named for the Rhine River. From then until the 1960s, only 2 metric tons of rhenium were produced worldwide. In 2004, worldwide production was 40 metric tons.

  20. 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

  1. Secondary victims of rape.

    PubMed

    Christiansen, Dorte; Bak, Rikke; Elklit, Ask

    2012-01-01

    Rape is often a very traumatic experience, which affects not only the primary victim (PV) but also his/her significant others. Studies on secondary victims of rape are few and have almost exclusively studied male partners of female rape victims. This study examined the impact of rape on 107 secondary victims, including family members, partners, and friends of male and female rape victims. We found that many respondents found it difficult to support the PV and that their relationship with the PV was often affected by the assault. Furthermore, the sample showed significant levels of traumatization, and it was estimated that approximately one quarter of the respondents suffered from posttraumatic stress syndrome (PTSD). Degree of traumatization was associated with a more recent assault, higher efforts to support the PV, recurrent thoughts about having been able to prevent the assault, a lack of social support for the respondent, and feeling let down by others. The respondents were generally interested in friend-, family-, and partner-focused interventions, particularly in receiving education about how best to support a rape victim.

  2. [Secondary stroke prevention].

    PubMed

    Ferro, J M; Correia, M; Freire, A; Perez y Sanchez, J; Abrunhosa, M A; Perez y Sanchez, M F

    1998-11-01

    The guidelines for secondary stroke prevention, graded following available scientific evidence, are presented. Stroke and TIA are defined and the indications for referral established. Basic assessment of stroke patients should include laboratory evaluation, ECG, brain CT, ultrasound examination of the extracranial vessels for events in the carotid distribution, and transthoracic or transesophageal echocardiogram if cardioembolism is suspected. The pharmacological and non-pharmacological reduction of blood pressure and serum cholesterol, stopping smoking and reducing alcohol intake are general measures recommended for secondary stroke prevention, together with healthier life-style changes (eating a Mediterranean type diet and performing regular moderate physical exercise). Concerning antithrombotic therapy, oral anticoagulants are recommended for patients with atrial fibrillation and other high to medium emboligenic cardiac risk conditions. Antiplatelet drugs are recommended for all other survivors of an ischemic cerebral event. Aspirin (75-325 mg/day) is the drug of choice. Alternative antiplatelet agents are clopidrogrel, ticlopidine, dipiridamol or triflusal. They can be used in patients with intolerance or contraindication to aspirin or in high-risk subjects. Endarterectomy of the symptomatic carotid is an additional procedure recommended for patients with ischemic stroke or TIA and carotid stenosis > 80% on the side of the symptomatic cerebral hemisphere. PMID:10021804

  3. Secondary Electron Emission Yields

    NASA Technical Reports Server (NTRS)

    Krainsky, I.; Lundin, W.; Gordon, W. L.; Hoffman, R. W.

    1981-01-01

    The secondary electron emission (SEE) characteristics for a variety of spacecraft materials were determined under UHV conditions using a commercial double pass CMA which permits sequential Auger electron electron spectroscopic analysis of the surface. The transparent conductive coating indium tin oxide (ITO) was examined on Kapton and borosilicate glass and indium oxide on FED Teflon. The total SEE coefficient ranges from 2.5 to 2.6 on as-received surfaces and from 1.5 to 1.6 on Ar(+) sputtered surfaces with 5 nm removed. A cylindrical sample carousel provides normal incidence of the primary beam as well as a multiple Faraday cup measurement of the approximately nA beam currents. Total and true secondary yields are obtained from target current measurements with biasing of the carousel. A primary beam pulsed mode to reduce electron beam dosage and minimize charging of insulating coatings was applied to Mg/F2 coated solar cell covers. Electron beam effects on ITO were found quite important at the current densities necessary to do Auger studies.

  4. [Primary and secondary hypocholesterolemia].

    PubMed

    Song, Jun-xian; Ren, Jing-yi; Chen, Hong

    2010-10-18

    Hypocholesterolemia is characterized by serum total cholesterol that is lower than the 5th percentile for age and sex, or the cut-off value which predicts the adverse prognosis by epidemiological study. Unlike hypercholesterolemia, physicians pay less attention to the morbidity, causes and consequences of hypocholesterolemia in clinical practice. In fact, hypocholesterolemia is a common dislipidemia, and mainly results from secondary factors. The causes of primary hypocholesterolemia are some disorders owing to genetic mutation in the pathway of cholesterol absorption, biosynthesis or metabolism, including abetalipoproteinemia, hypobetalipoproteinemia, Tangier disease, chylomicron retention disease and inherited disorders of cholesterol biosynthesis. The causes of secondary hypocholesterolemia comprise anemia, hyperthyroidism, malignancy, live disease, critical illness, serious stress, malabsorption or malnutrition, acute or chronic infection, chronic inflammation, and use of some drugs. In addition, what's more important is that hypocholesterolemia can result in some adverse events, such as increased mortality, intracerebral hemorrhage, cancer, infection, adrenal failure, suicide and mental disorder. Therefore, with the practice of intensive lipid-lowering treatment and the tendency to the increased indications of statins, it's high time that physicians attached more importance to hypocholesterolemia. PMID:20957025

  5. [Melanoma secondary prevention].

    PubMed

    Suppa, M; Daxhelet, M; del Marmol, V

    2015-09-01

    Melanoma represents a major public health problem. Its incidence is constantly rising and the mortality rate can be frightfully important if the diagnosis is delayed. Melanoma also exerts a significant economical burden on the society. Therefore there is a need of concrete and pragmatic public health strategies in order to enhance melanoma prevention. Primary prevention of melanoma consists in avoiding excessive exposure to ultraviolet rays,'which represent the main risk factor for the disease occurrence. Secondary prevention is a synonym of melanoma early diagnosis and can be obtained by means of two methods : patients' self-examination and medical examination. Both these examinations must be routinely and thoroughly performed, must be based on the ABCDE rule and the ugly duckling sign, and ideally must be aided by the use of total-body photography. Current international guidelines suggest that all cutaneous screenings should be performed using dermoscopy, a non-invasive imaging technique that allows improving considerably the diagnostic performance. More sophisticated imaging techniques, such as confocal microscopy, are also available in specialised centres. The current scientific evidence supports the efficacy of melanoma primary and secondary prevention programs as a tool to decrease melanoma mortality. Many skin cancer prevention campaigns have been organised worldwide. The most famous and successful in Europe is Euromelanoma.

  6. Chemical Bonding in Sulfide Minerals

    SciTech Connect

    Vaughan, David J.; Rosso, Kevin M.

    2006-08-01

    An understanding of chemical bonding and electronic structure in sulfide minerals is central to any attempt at understanding their crystal structures, stabilities and physical properties. It is also an essential precursor to understanding reactivity through modeling surface structure at the molecular scale. In recent decades, there have been remarkable advances in first principles (ab initio) methods for the quantitative calculation of electronic structure. These advances have been made possible by the very rapid development of high performance computers. Several review volumes that chart the applications of these developments in mineralogy and geochemistry are available (Tossell and Vaughan, 1992; Cygan and Kubicki, 2001). An important feature of the sulfide minerals is the diversity of their electronic structures, as evidenced by their electrical and magnetic properties (see Pearce et al. 2006, this volume). Thus, sulfide minerals range from insulators through semiconductors to metals, and exhibit every type of magnetic behavior. This has presented problems for those attempting to develop bonding models for sulfides, and also led to certain misconceptions regarding the kinds of models that may be appropriate. In this chapter, chemical bonding and electronic structure models for sulfides are reviewed with emphasis on more recent developments. Although the fully ab initio quantitative methods are now capable of a remarkable degree of sophistication in terms of agreement with experiment and potential to interpret and predict behavior with varying conditions, both qualitative and more simplistic quantitative approaches will also be briefly discussed. This is because we believe that the insights which they provide are still helpful to those studying sulfide minerals. In addition to the application of electronic structure models and calculations to solid sulfides, work on sulfide mineral surfaces (Rosso and Vaughan 2006a,b) and solution complexes and clusters (Rickard

  7. Uranium mineralization in the two mica granite of gabal Ribdab area, South Eastern Desert, Egypt.

    PubMed

    Ibrahim, M E; Saleh, G M; Abd El-Naby, H H

    2001-12-01

    Among the different rock units in the Gabal Ribdab area, the two-mica leucogranite and muscovite pegmatitic granite are the most favourable host rocks for uranium and thorium mineralization. The muscovite pegmatitic granite shows evidence of post-magmatic alteration, e.g. Na- and K-metasomatism, whereas the two-mica leucogranite could be regarded as being fresh. The spectrometric survey revealed the presence of three enriched zones with a maximum eU content of 140 ppm and the maximum eTh is 36 ppm. Uranophane, zippeite and becquerelite are the most abundant uranium minerals. The origin of these secondary minerals is mainly related to alteration of primary minerals by the action of oxidizing fluids, mobilization of uranium and then redeposition in other forms. Redistribution by circulating meteoric waters might have taken place.

  8. U.S. Geological Survey Mineral Resources Program—Mineral resource science supporting informed decisionmaking

    USGS Publications Warehouse

    Wilkins, Aleeza M.; Doebrich, Jeff L.

    2016-09-19

    The USGS Mineral Resources Program (MRP) delivers unbiased science and information to increase understanding of mineral resource potential, production, and consumption, and how mineral resources interact with the environment. The MRP is the Federal Government’s sole source for this mineral resource science and information. Program goals are to (1) increase understanding of mineral resource formation, (2) provide mineral resource inventories and assessments, (3) broaden knowledge of the effects of mineral resources on the environment and society, and (4) provide analysis on the availability and reliability of mineral supplies.

  9. Quantifying elemental compositions of primary minerals from granitic rocks and saprolite within the Santa Catalina Mountain Critical Zone Observatory

    NASA Astrophysics Data System (ADS)

    Lybrand, R. A.; Rasmussen, C.

    2011-12-01

    Granitic terrain comprises a significant area of the earth's land surface (>15%). Quantifying weathering processes involved in the transformation of granitic rock to saprolite and soil is central to understanding landscape evolution in these systems. The quantification of primary mineral composition is important for assessing subsequent mineral transformations and soil production. This study focuses on coupling detailed analysis of primary mineral composition to soil development across an array of field sites sampled from the Santa Catalina Mountain Critical Zone observatory (SCM-CZO) environmental gradient. The gradient spans substantial climate-driven shifts in vegetation, ranging from desert scrub to mixed conifer forests. The parent material is a combination of Precambrian and Tertiary aged granites and quartz diorite. Primary mineral type and composition are known to vary among the various aged granitic materials and this variability is hypothesized to manifest as significant variation in regolith forming processes across the SCM-CZO. To address this variability, the mineral composition and mineral formulae of rock and saprolite samples were determined by electron microprobe chemical analyses. The rocks were pre-dominantly quartz, biotite, muscovite, orthoclase and calcium/sodium-rich plagioclase feldspars. Trace minerals observed in the samples included sphene, rutile, zircon, garnet, ilmenite, and apatite. Mineral formulae from electron microprobe analyses were combined with quantitative x-ray diffraction (QXRD) and x-ray fluorescence (XRF) data to quantify both primary and secondary mineralogical components in soil profiles from each of the field sites. Further, electron microprobe analyses of <2mm mixed conifer saprolite revealed weathered plagioclase grains coated with clay-sized particles enriched in silica and aluminum (~25% and 15%, respectively), suggesting kaolin as the secondary phase. The coatings were interspersed within each plagioclase grain, a

  10. Equilibrium of Groundwater with Carbonate Minerals of the Water-Bearing Rocks under Anthropogenic Impact (by the example of Kishinev, Moldova)

    NASA Astrophysics Data System (ADS)

    Timoshenkova, A. N.; Pasechnik, E. Yu; Tokarenko, O. G.

    2014-08-01

    The paper presents calculation results of equilibrium of groundwater in Kishenev with a variety of secondary carbonate minerals. It is shown that the groundwater-rock system is in equilibrium with some minerals, such as calcite, magnesite, dolomite, siderite, but at the same time is not in equilibrium with strontianite. It indicates that secondary mineral precipitation is possible. Specific nitrate chemical water type, which is rarely observed in nature and characterized by the presence of anthropogenic impact in this territory, in some cases is of higher saturation as compared to calcite, dolomite and magnesite due to the fact that nitrate ion content increases with the increase of calcium content.

  11. Organo-mineral complexation alters carbon and nitrogen cycling in stream microbial assemblages

    NASA Astrophysics Data System (ADS)

    Hunter, William Ross; Wanek, Wolfgang; Prommer, Judith; Mooshammer, Maria; Battin, Tom

    2014-05-01

    Inland waters are of global biogeochemical importance receiving carbon inputs of ~ 4.8 Pg C y-1. Of this 12 % is buried, 18 % transported to the oceans, and 70 % supports aquatic secondary production. However, the mechanisms that determine the fate of organic matter (OM) in these systems are poorly defined. One important aspect is the formation of organo-mineral complexes in aquatic systems and their potential as a route for OM transport and burial vs. microbial utilization as organic carbon (C) and nitrogen (N) sources. Organo-mineral particles form by sorption of dissolved OM to freshly eroded mineral surfaces and may contribute to ecosystem-scale particulate OM fluxes. We tested the availability of mineral-sorbed OM as a C & N source for streamwater microbial assemblages and streambed biofilms. Organo-mineral particles were constructed in vitro by sorption of 13C:15N-labelled amino acids to hydrated kaolin particles, and microbial degradation of these particles compared with equivalent doses of 13C:15N-labelled free amino acids. Experiments were conducted in 120 ml mesocosms over 7 days using biofilms and streamwater sampled from the Oberer Seebach stream (Austria), tracing assimilation and mineralization of 13C and 15N labels from mineral-sorbed and dissolved amino acids. Here we present data on the effects of organo-mineral sorption upon amino acid mineralization and its C:N stoichiometry. Organo-mineral sorption had a significant effect upon microbial activity, restricting C and N mineralization by both the biofilm and streamwater treatments. Distinct differences in community response were observed, with both dissolved and mineral-stabilized amino acids playing an enhanced role in the metabolism of the streamwater microbial community. Mineral-sorption of amino acids differentially affected C & N mineralization and reduced the C:N ratio of the dissolved amino acid pool. The present study demonstrates that organo-mineral complexes restrict microbial degradation

  12. Primary and secondary hypohedonia.

    PubMed

    Meehl, P E

    2001-02-01

    Having shown taxometrically that there exists a hypohedonic schizotypal taxon in a college population, J. J. Blanchard, S. W. Gangestad, S. A. Brown, and W. P. Horan (2000) suggested that P. E. Meehl erred in revising his 1962 theory by postulating a normal-range individual differences variable of hedonic capacity that potentiates schizotypy into schizophrenia. The aversive drift and secondary anhedonia of Meehl's theory imply that the schizotypal taxon will generate hypohedonic taxonicity in an adult population. Psychometrically measurable hedonic disposition (as distinguished from genetic primary hedonic capacity) is "dragged along" by the schizogene, especially in the social domain. To choose between causal interpretations, it could be ascertained whether the schizotypal anhedonic taxon is composed of individuals who are schizotaxic on the basis of psychophysiological, cognitive, and soft neurologic indicators.

  13. Management of secondary peritonitis.

    PubMed Central

    Wittmann, D H; Schein, M; Condon, R E

    1996-01-01

    OBJECTIVE. The authors review current definition, classification, scoring, microbiology, inflammatory response, and goals of management of secondary peritonitis. SUMMARY BACKGROUND DATA. Despite improved diagnostic modalities, potent antibiotics, modern intensive care, and aggressive surgical treatment, up to one third of patients still die of severe secondary peritonitis. Against the background of current understanding of the local and systemic inflammatory response associated with peritonitis, there is growing controversy concerning the optimal antibiotic and operative therapy, intensified by lack of properly conducted randomized studies. In this overview the authors attempt to outline controversies, suggest a practical clinical approach, and highlight issues necessitating further research. METHODS. The authors review the literature and report their experience. RESULTS. The emerging concepts concerning antibiotic treatment suggest that less-in terms of the number of drugs and the duration of treatment-is better. The classical single operation for peritonitis, which obliterates the source of infection and purges the peritoneal cavity, may be inadequate for severe forms of peritonitis; for the latter, more aggressive surgical techniques are necessary to decompress increased intra-abdominal pressure and prevent or treat persistent and recurrent infection. The widespread acceptance of the more aggressive and demanding surgical methods has been hampered by the lack of randomized trials and reportedly high associated morbidity rates. CONCLUSIONS. Sepsis represents the host's systemic inflammatory response to bacterial peritonitis. To improve results, both the initiator and the biologic consequences of the peritoneal infective-inflammatory process should be addressed. The initiator may be better controlled in severe forms of peritonitis by aggressive surgical methods, whereas the search for methods to abort its systemic consequences is continuing. PMID:8678610

  14. Vitamin and Mineral Supplement Fact Sheets

    MedlinePlus

    ... Tables Online DRI Tool Daily Value (DV) Tables Vitamin and Mineral Supplement Fact Sheets Search the list ... Supplements: Background Information Botanical Dietary Supplements: Background Information Vitamin and Mineral Fact Sheets Botanical Supplement Fact Sheets ...

  15. Mineral Resources, Economic Growth, and World Population

    ERIC Educational Resources Information Center

    Brooks, David B.; Andrews, P. W.

    1974-01-01

    World mineral supply and demand is discussed. The economics of future mineral availability in terms of effects on pollution, land use, energy consumption, human settlements, and the international distribution of income are emphasized. (DT)

  16. USSR and Afghanistan mineral resources

    SciTech Connect

    Shroder, J.F. Jr.

    1983-01-01

    Afghanistan is a geological complex in which plentiful minerals and fuels were formed. Western geologists explored that country during the last 100 years and produced many reports and maps. Real progress in a systematic analysis, however, was not made until the intensive efforts of the Soviet Union during the past two decades. By diplomatic and economic maneuvers, the Soviets took control of Afghanistan's nascent hydrocarbon indusry during the 1960s. Following the 1973 coup, the Soviets and Afghan supporters replaced pro-Western technical advisors and hampered Western-linked development. Intensive field investgations led to the discovery of hundreds of mineral deposits and several good petroleum prospects. The current Russian military occupation is partially subsidized with Afghanistan resources. 83 references, 3 figures, 3 tables.

  17. Quarterly minerals outlook, June 1983

    SciTech Connect

    Glass, G.B.

    1983-01-01

    An overview is presented of the mineral industry of Wyoming. Petroleum production shows a slight annual decline. Many producers have been shutting in their natural gas wells due to the sharp decline in demand. Activities in the base, precious, and ferrous metals industry are summarized. Uranium and trona production is down from the previous year. Other minerals mentioned are gypsum, limestone, bentonite, and phosphorus. Production of coal is given by county. Electric utilities have not used all the coal they bought last year, and construction of several power plants have been delayed indefinitely. Underground coal gasification projects are mentioned. Tables present production forecasts for coal to 1990, for oil and gas to 1988, and for uranium and trona to 1987. 5 tables.

  18. Iron phase transformations resulting from the respiration of Shewanella putrefaciens on a mixed mineral phase

    NASA Astrophysics Data System (ADS)

    Boyanov, M. I.; O'Loughlin, E. J.; Kemner, K. M.

    2009-11-01

    The initial Fe(III) minerals and the secondary mineralization products of Shewanella putrefaciens CN32 grown in the presence of dissolved phosphate and a commercial Fe(III) oxide, nominally nanoparticulate lepidocrocite, were determined using XRD and XAFS. The starting material was transformed by the bacteria from a reddish brown, rust colour mineral to a dark green phase over 90 days. Acid extraction of the bioreduced solids with 0.75 M HCl recovered 83% of the total iron as Fe(II), leaving a solid, acid-resistant phase. The latter was identified as nanoparticulate hematite by EXAFS. Subsequently, the starting Fe(III) phase was determined to be a mixture of 60% lepidocrocite, 26% ferrihydrite, and 14% hematite, using linear combination EXAFS analysis. For the acid-extractable phase, XANES and EXAFS indicated a predominantly Fe(II) valence state and a spectrum consistent with a mixture of brucite-type minerals(e.g., green rust or ferrous hydroxide) and siderite. The observed transformations suggest that in this mixed-mineral system, lepidocrocite and ferrihydrite are readily reducible to green rust and siderite, whereas hematite is less amenable to bacterial reduction. This study also demonstrates the utility of XAFS spectroscopy in the quantitative characterization of dissimilatory metal transformations, particularly in complex systems such as nanoparticulate minerals in hydrated mineral-bacteria assemblages.

  19. Calcioolivine, γ-Ca2SiO4, an old and New Mineral species

    NASA Astrophysics Data System (ADS)

    Zadov, A. E.; Gazeev, V. M.; Pertsev, N. N.; Gurbanov, A. G.; Gobechiya, E. R.; Yamnova, N. A.; Chukanov, N. V.

    2009-12-01

    Calcioolivine has been included into the MDI mineral database in the list of grandfathered minerals. Its history, together with related artificial compounds, is extremely complex: various minerals and compounds received this name, including natural orthorhombic Ca orthosilicate. In this paper, the crystal structure and properties of natural calcioolivine are described for the first time. The new mineral has been found at Mt. Lakargi, Upper Chegem Plateau, the northern Caucasus, Kabarda-Balkaria Republic, Russia. It has been identified in skarnified, primary carbonate xenoliths entrained by middle to late Pliocene silicic ignimbrites of the Upper Chegem caldera. These xenoliths of a few centimeters to a few meters in size are located close to the volcanic vent. Calcioolivine rims relics of larnite and occurs as relict grains among crystals of spurrite, rondorfite, wadalite or secondary hillebrandite, afwillite, thaumasite, and ettringite. Hillebrandite is the major product of alteration of calcioolivine; larnite is relatively more resistant to low-temperature alteration. Spurrite, larnite, tilleyite, kilchoanite, cuspidine, wadalite, rondorfite, reinhardbraunsite, lakargiite (CaZrO3), members of ellestadite series, afwillite, ettringite, katoite, and thaumasite are associated minerals. It is inferred that calcioolivine has been produced as a result of interaction of host carbonate rocks in xenoliths with volcanic lava and gases during eruption. The name calcioolivine was approved by the Commission on New Minerals and Mineral Names, International Mineralogical Association, September 6, 2007 (no. 07-B).

  20. Characterization and implications of dickite-mineralized fractures in Mesaverde core from Piceance Creek basin

    SciTech Connect

    Finley, S.J.; Lorenz, J.C.

    1989-03-01

    The presence of authigenic dickite, a polymorph of kaolinite, in fractures in the gas-productive Mesaverde Formation of the Piceance Creek basin may indicate a locally interconnected fracture system. Core used in this study is from the US Department of Energy's Multiwell Experiment located in the Rulison field in northwestern Colorado. The Mesaverde is fractured throughout the 4000-ft section cored at this location. Although spray calcite is the most common fracture mineralization throughout the section, dickite mineralization commonly occurs as a secondary phase in fractures within a roughly 400 ft-thick interval. The petrography of the host rock where these fractures are concentrated is similar to the petrography of other core intervals where dickite mineralization and/or irregular fractures were not detected. No apparent difference is seen in the mineral constituents or the diagenetic alteration of the minerals present, suggesting that the source of the dickite may have been extraformational. If the dickite is extraformational, the variation in the orientations of these anomalous dickite-mineralized fractures, coupled with the presence of dickite on some other types of fractures, implies that at some time in the depositional and burial history of the rock the dickite fractures represented an interconnected fracture system. Microporosity is associated with the dickite mineralization, and this fracture system may still be locally interconnected and permeable making this a potentially gas-productive interval. Special consideration of drilling and/or stimulation fluid interaction with dickite may be necessary.

  1. Minerals

    MedlinePlus

    ... yogurt legumes, such as beans, split peas, and lentils Zinc Zinc helps your immune system, which is ... peanuts legumes, such as beans, split peas, and lentils When people don't get enough of these ...

  2. Minerals

    Technology Transfer Automated Retrieval System (TEKTRAN)

    Over the past two decades, the aquaculture industry has expanded rapidly throughout the world and is expected to continue to grow in the years to come due to the high cost of harvesting fish from the oceans, the un-sustainability of ocean fishing methods, and the increased demand for fish as a resul...

  3. Miners custom-make trailer

    SciTech Connect

    Not Available

    1987-06-01

    The Maintenance Department at Glenharold Mine in Stanton, North Dakota, has developed a custom solution to a nagging problem. Employees have fabricated a flatbed trailer to haul large equipment and have saved the mine the expense of investing in a new tractor-trailer. Using Lincoln Electric's Jetweld LH-100M to fillet weld Tl steel, the miners constructed a 200-t-capacity flatbed from scraps. The trailer can haul a D-10 bulldozer or a 60 cu-yd dragline bucket.

  4. Evaporites, petroleum and mineral resources

    SciTech Connect

    Melvin, J.L.

    1991-01-01

    This book illustrates the expanding knowledge of evaporites as important reservoir seals, fluid aquitards, ore-hosting sediments, and economically viable sediments in their own right. Researchers, oil and gas professionals, minerals resource professionals, environmental specialists and others within geology and the other earth sciences shall utilize the information within this book in their understanding of the many recent discoveries and concepts involved in the field of evaporite sedimentology.

  5. 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.

  6. Oral Manifestations of Secondary Syphilis.

    PubMed

    de Paulo, Luiz Fernando Barbosa; Servato, João Paulo Silva; Oliveira, Maiolino Thomaz Fonseca; Durighetto, Antonio Francisco; Zanetta-Barbosa, Darceny

    2015-06-01

    Known as "the great imitator," secondary syphilis may clinically manifest itself in myriad ways, involving different organs including the oral mucosa, and mimicking, both clinically and histologically, several diseases, thereby making diagnosis a challenge for clinicians. We highlight the clinical aspects of oral manifestation in 7 patients with secondary syphilis. Clinicians should consider secondary syphilis in the differential diagnosis of ulcerative and/or white oral lesions.

  7. Oral Manifestations of Secondary Syphilis.

    PubMed

    de Paulo, Luiz Fernando Barbosa; Servato, João Paulo Silva; Oliveira, Maiolino Thomaz Fonseca; Durighetto, Antonio Francisco; Zanetta-Barbosa, Darceny

    2015-06-01

    Known as "the great imitator," secondary syphilis may clinically manifest itself in myriad ways, involving different organs including the oral mucosa, and mimicking, both clinically and histologically, several diseases, thereby making diagnosis a challenge for clinicians. We highlight the clinical aspects of oral manifestation in 7 patients with secondary syphilis. Clinicians should consider secondary syphilis in the differential diagnosis of ulcerative and/or white oral lesions. PMID:25892249

  8. Mine and mineral occurrences of Afghanistan

    USGS Publications Warehouse

    Orris, G.J.; Bliss, J.D.

    2002-01-01

    This inventory of more than 1000 mines and mineral occurrences in Afghanistan was compiled from published literature and the files of project members of the National Industrial Minerals project of the U.S. Geological Survey. The compiled data have been edited for consistency and most duplicates have been deleted. The data cover metals, industrial minerals, coal, and peat. Listings in the table represent several levels of information, including mines, mineral showings, deposits, and pegmatite fields.

  9. Drivers of Phosphorus Uptake by Barley Following Secondary Resource Application

    PubMed Central

    Brod, Eva; Øgaard, Anne Falk; Krogstad, Tore; Haraldsen, Trond Knapp; Frossard, Emmanuel; Oberson, Astrid

    2016-01-01

    Minable rock phosphate is a finite resource. Replacing mineral phosphorus (P) fertilizer with P-rich secondary resources is one way to manage P more efficiently, but the importance of physicochemical and microbial soil processes induced by secondary resources for plant P uptake is still poorly understood. Using radioactive-labeling techniques, the fertilization effects of dairy manure, fish sludge, meat bone meal, and wood ash were studied as P uptake by barley after 44 days and compared with those of water-soluble mineral P (MinP) and an unfertilized control (NoP) in a pot experiment with an agricultural soil containing little available P at two soil pH levels, approximately pH 5.3 (unlimed soil) and pH 6.2 (limed soil). In a parallel incubation experiment, the effects of the secondary resources on physicochemical and microbial soil processes were studied. The results showed that the relative agronomic efficiency compared with MinP decreased in the order: manure ≥fish sludge ≥wood ash ≥meat bone meal. The solubility of inorganic P in secondary resources was the main driver for P uptake by barley (Hordeum vulgare). The effects of secondary resources on physicochemical and microbial soil processes were of little overall importance. Application of organic carbon with manure resulted in microbial P immobilization and decreased uptake by barley of P derived from the soil. On both soils, P uptake by barley was best explained by a positive linear relationship with the H2O + NaHCO3-soluble inorganic P fraction in fertilizers or by a linear negative relationship with the HCl-soluble inorganic P fraction in fertilizers. PMID:27243015

  10. Drivers of Phosphorus Uptake by Barley Following Secondary Resource Application.

    PubMed

    Brod, Eva; Øgaard, Anne Falk; Krogstad, Tore; Haraldsen, Trond Knapp; Frossard, Emmanuel; Oberson, Astrid

    2016-01-01

    Minable rock phosphate is a finite resource. Replacing mineral phosphorus (P) fertilizer with P-rich secondary resources is one way to manage P more efficiently, but the importance of physicochemical and microbial soil processes induced by secondary resources for plant P uptake is still poorly understood. Using radioactive-labeling techniques, the fertilization effects of dairy manure, fish sludge, meat bone meal, and wood ash were studied as P uptake by barley after 44 days and compared with those of water-soluble mineral P (MinP) and an unfertilized control (NoP) in a pot experiment with an agricultural soil containing little available P at two soil pH levels, approximately pH 5.3 (unlimed soil) and pH 6.2 (limed soil). In a parallel incubation experiment, the effects of the secondary resources on physicochemical and microbial soil processes were studied. The results showed that the relative agronomic efficiency compared with MinP decreased in the order: manure ≥fish sludge ≥wood ash ≥meat bone meal. The solubility of inorganic P in secondary resources was the main driver for P uptake by barley (Hordeum vulgare). The effects of secondary resources on physicochemical and microbial soil processes were of little overall importance. Application of organic carbon with manure resulted in microbial P immobilization and decreased uptake by barley of P derived from the soil. On both soils, P uptake by barley was best explained by a positive linear relationship with the H2O + NaHCO3-soluble inorganic P fraction in fertilizers or by a linear negative relationship with the HCl-soluble inorganic P fraction in fertilizers. PMID:27243015

  11. Is Struvite a Prebiotic Mineral?

    PubMed Central

    Gull, Maheen; Pasek, Matthew A.

    2013-01-01

    The prebiotic relevance of mineral struvite, MgNH4PO4·6H2O, was studied experimentally as a phosphorylating reagent and, theoretically, to understand the geochemical requirements for its formation. The effectiveness of phosphorylation by the phosphate mineral, monetite, CaHPO4, was also studied to compare to the efficiency of struvite. The experiments focused on the phosphorylation reactions of the minerals with organic compounds, such as nucleosides, glycerol and choline chloride, and heat at 75 °C for about 7–8 days and showed up to 28% phosphorylation of glycerol. In contrast, the compositional requirements for the precipitation of struvite are high ammonium and phosphate concentrations, as well as a little Ca2+ dissolved in the water. Combined, these requirements suggest that it is not likely that struvite was present in excess on the early Earth to carry out phosphorylation reactions. The present study focuses on the thermodynamic aspects of struvite formation, complementing the results given by Orgel and Handschuh (1973), which were based on the kinetic effects. PMID:25369744

  12. Raising Environmental Awareness among Miners in Iran

    ERIC Educational Resources Information Center

    Mozaffari, Ezatollah

    2013-01-01

    Generation of waste is inevitable but controllable in minerals industry. The aim of this research is to find ways for raising environmental awareness among miners. Miners' attitude towards environmental mining has been investigated. A survey has been done collecting mine managers' point of view coupled with current trend on mine waste management…

  13. MARINE MINERAL RESOURCES - AN UPDATE AND INTRODUCTION.

    USGS Publications Warehouse

    Cruickshank, Michael J.; Siapno, William

    1985-01-01

    This article briefly traces the status of marine minerals development, and it describes papers presented in this special issue on the subject. Subjects covered include types of deposits, marine mining in Canada, Manganese nodules, metalliferous sulfides as seabed minerals, metallurgical processes for reducing sulfide minerals, U. S. phosphate industry, construction materials and placers, and industry problems.

  14. 30 CFR 57.5070 - Miner training.

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... 30 Mineral Resources 1 2014-07-01 2014-07-01 false Miner training. 57.5070 Section 57.5070 Mineral Resources MINE SAFETY AND HEALTH ADMINISTRATION, DEPARTMENT OF LABOR METAL AND NONMETAL MINE SAFETY AND HEALTH SAFETY AND HEALTH STANDARDS-UNDERGROUND METAL AND NONMETAL MINES Air Quality, Radiation,...

  15. 30 CFR 57.5070 - Miner training.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... 30 Mineral Resources 1 2011-07-01 2011-07-01 false Miner training. 57.5070 Section 57.5070 Mineral Resources MINE SAFETY AND HEALTH ADMINISTRATION, DEPARTMENT OF LABOR METAL AND NONMETAL MINE SAFETY AND HEALTH SAFETY AND HEALTH STANDARDS-UNDERGROUND METAL AND NONMETAL MINES Air Quality, Radiation, Physical Agents, and Diesel Particulate...

  16. 30 CFR 57.5070 - Miner training.

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... 30 Mineral Resources 1 2013-07-01 2013-07-01 false Miner training. 57.5070 Section 57.5070 Mineral Resources MINE SAFETY AND HEALTH ADMINISTRATION, DEPARTMENT OF LABOR METAL AND NONMETAL MINE SAFETY AND HEALTH SAFETY AND HEALTH STANDARDS-UNDERGROUND METAL AND NONMETAL MINES Air Quality, Radiation,...

  17. 36 CFR 331.17 - Minerals.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... 36 Parks, Forests, and Public Property 3 2011-07-01 2011-07-01 false Minerals. 331.17 Section 331..., KENTUCKY AND INDIANA § 331.17 Minerals. All activities in connection with prospecting, exploration, development, mining or other removal or the processing of mineral resources and all uses reasonably...

  18. 36 CFR 331.17 - Minerals.

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... 36 Parks, Forests, and Public Property 3 2014-07-01 2014-07-01 false Minerals. 331.17 Section 331..., KENTUCKY AND INDIANA § 331.17 Minerals. All activities in connection with prospecting, exploration, development, mining or other removal or the processing of mineral resources and all uses reasonably...

  19. 36 CFR 331.17 - Minerals.

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... 36 Parks, Forests, and Public Property 3 2013-07-01 2012-07-01 true Minerals. 331.17 Section 331..., KENTUCKY AND INDIANA § 331.17 Minerals. All activities in connection with prospecting, exploration, development, mining or other removal or the processing of mineral resources and all uses reasonably...

  20. 36 CFR 331.17 - Minerals.

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... 36 Parks, Forests, and Public Property 3 2012-07-01 2012-07-01 false Minerals. 331.17 Section 331..., KENTUCKY AND INDIANA § 331.17 Minerals. All activities in connection with prospecting, exploration, development, mining or other removal or the processing of mineral resources and all uses reasonably...