Sample records for mineral electronic components

  1. 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.

  2. Extracellular electron transfer mechanisms between microorganisms and minerals.

    PubMed

    Shi, Liang; Dong, Hailiang; Reguera, Gemma; Beyenal, Haluk; Lu, Anhuai; Liu, Juan; Yu, Han-Qing; Fredrickson, James K

    2016-10-01

    Electrons can be transferred from microorganisms to multivalent metal ions that are associated with minerals and vice versa. As the microbial cell envelope is neither physically permeable to minerals nor electrically conductive, microorganisms have evolved strategies to exchange electrons with extracellular minerals. In this Review, we discuss the molecular mechanisms that underlie the ability of microorganisms to exchange electrons, such as c-type cytochromes and microbial nanowires, with extracellular minerals and with microorganisms of the same or different species. Microorganisms that have extracellular electron transfer capability can be used for biotechnological applications, including bioremediation, biomining and the production of biofuels and nanomaterials.

  3. Extracellular electron transfer mechanisms between microorganisms and minerals

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Shi, Liang; Dong, Hailiang; Reguera, Gemma

    Electrons can be transferred from microorganisms to multivalent metal ions that are associated with minerals and vice versa. As the microbial cell envelope is neither physically permeable to minerals nor electrically conductive, microorganisms have evolved strategies to exchange electrons with extracellular minerals. In this Review, we discuss the molecular mechanisms that underlie the ability of microorganisms to exchange electrons, such as c-type cytochromes and microbial nanowires, with extracellular minerals and with microorganisms of the same or different species. Microorganisms that have extracellular electron transfer capability can be used for biotechnological applications, including bioremediation, biomining and the production of biofuels andmore » nanomaterials.« less

  4. Electron Transfer Strategies Regulate Carbonate Mineral and Micropore Formation.

    PubMed

    Zeng, Zhirui; Tice, Michael M

    2018-01-01

    Some microbial carbonates are robust biosignatures due to their distinct morphologies and compositions. However, whether carbonates induced by microbial iron reduction have such features is unknown. Iron-reducing bacteria use various strategies to transfer electrons to iron oxide minerals (e.g., membrane-bound enzymes, soluble electron shuttles, nanowires, as well as different mechanisms for moving over or attaching to mineral surfaces). This diversity has the potential to create mineral biosignatures through manipulating the microenvironments in which carbonate precipitation occurs. We used Shewanella oneidensis MR-1, Geothrix fermentans, and Geobacter metallireducens GS-15, representing three different strategies, to reduce solid ferric hydroxide in order to evaluate their influence on carbonate and micropore formation (micro-size porosity in mineral rocks). Our results indicate that electron transfer strategies determined the morphology (rhombohedral, spherical, or long-chained) of precipitated calcium-rich siderite by controlling the level of carbonate saturation and the location of carbonate formation. Remarkably, electron transfer strategies also produced distinctive cell-shaped micropores in both carbonate and hydroxide minerals, thus producing suites of features that could potentially serve as biosignatures recording information about the sizes, shapes, and physiologies of iron-reducing organisms. Key Words: Microbial iron reduction-Micropore-Electron transfer strategies-Microbial carbonate. Astrobiology 18, 28-36.

  5. Cooling system for electronic components

    DOEpatents

    Anderl, William James; Colgan, Evan George; Gerken, James Dorance; Marroquin, Christopher Michael; Tian, Shurong

    2015-12-15

    Embodiments of the present invention provide for non interruptive fluid cooling of an electronic enclosure. One or more electronic component packages may be removable from a circuit card having a fluid flow system. When installed, the electronic component packages are coincident to and in a thermal relationship with the fluid flow system. If a particular electronic component package becomes non-functional, it may be removed from the electronic enclosure without affecting either the fluid flow system or other neighboring electronic component packages.

  6. Cooling system for electronic components

    DOEpatents

    Anderl, William James; Colgan, Evan George; Gerken, James Dorance; Marroquin, Christopher Michael; Tian, Shurong

    2016-05-17

    Embodiments of the present invention provide for non interruptive fluid cooling of an electronic enclosure. One or more electronic component packages may be removable from a circuit card having a fluid flow system. When installed, the electronic component packages are coincident to and in a thermal relationship with the fluid flow system. If a particular electronic component package becomes non-functional, it may be removed from the electronic enclosure without affecting either the fluid flow system or other neighboring electronic component packages.

  7. Transmission Electron Microscopy of Minerals and Rocks

    NASA Astrophysics Data System (ADS)

    McLaren, Alex C.

    1991-04-01

    Of the many techniques that have been applied to the study of crystal defects, none has contributed more to our understanding of their nature and influence on the physical and chemical properties of crystalline materials than transmission electron microscopy (TEM). TEM is now used extensively by an increasing number of earth scientists for direct observation of defect microstructures in minerals and rocks. Transmission Electron Microscopy of Rocks and Minerals is an introduction to the principles of the technique and is the only book to date on the subject written specifically for geologists and mineralogists. The first part of the book deals with the essential physics of the transmission electron microscope and presents the basic theoretical background required for the interpretation of images and electron diffraction patterns. The final chapters are concerned with specific applications of TEM in mineralogy and deal with such topics as planar defects, intergrowths, radiation-induced defects, dislocations and deformation-induced microstructures. The examples cover a wide range of rock-forming minerals from crustal rocks to those in the lower mantle, and also take into account the role of defects in important mineralogical and geological processes.

  8. Electron Transfer Strategies Regulate Carbonate Mineral and Micropore Formation

    NASA Astrophysics Data System (ADS)

    Zeng, Zhirui; Tice, Michael M.

    2018-01-01

    Some microbial carbonates are robust biosignatures due to their distinct morphologies and compositions. However, whether carbonates induced by microbial iron reduction have such features is unknown. Iron-reducing bacteria use various strategies to transfer electrons to iron oxide minerals (e.g., membrane-bound enzymes, soluble electron shuttles, nanowires, as well as different mechanisms for moving over or attaching to mineral surfaces). This diversity has the potential to create mineral biosignatures through manipulating the microenvironments in which carbonate precipitation occurs. We used Shewanella oneidensis MR-1, Geothrix fermentans, and Geobacter metallireducens GS-15, representing three different strategies, to reduce solid ferric hydroxide in order to evaluate their influence on carbonate and micropore formation (micro-size porosity in mineral rocks). Our results indicate that electron transfer strategies determined the morphology (rhombohedral, spherical, or long-chained) of precipitated calcium-rich siderite by controlling the level of carbonate saturation and the location of carbonate formation. Remarkably, electron transfer strategies also produced distinctive cell-shaped micropores in both carbonate and hydroxide minerals, thus producing suites of features that could potentially serve as biosignatures recording information about the sizes, shapes, and physiologies of iron-reducing organisms.

  9. Electron Transfer Between Electrically Conductive Minerals and Quinones

    NASA Astrophysics Data System (ADS)

    Taran, Olga

    2017-07-01

    Long-distance electron transfer in marine environments couples physically separated redox half-reactions, impacting biogeochemical cycles of iron, sulfur and carbon. Bacterial bio-electrochemical systems that facilitate electron transfer via conductive filaments or across man-made electrodes are well known, but the impact of abiotic currents across naturally occurring conductive and semiconducitve minerals is poorly understood. In this paper I use cyclic voltammetry to explore electron transfer between electrodes made of common iron minerals (magnetite, hematite, pyrite, pyrrhotite, mackinawite and greigite), and hydroquinones - a class of organic molecules found in carbon-rich sediments. Of all tested minerals, only pyrite and magnetite showed an increase in electric current in the presence of organic molecules, with pyrite showing excellent electrocatalytic performance. Pyrite electrodes performed better than commercially available glassy carbon electrodes and showed higher peak currents, lower overpotential values and a smaller separation between oxidation and reduction peaks for each tested quinone. Hydroquinone oxidation on pyrite surfaces was reversible, diffusion controlled, and stable over a large number of potential cycles. Given the ubiquity of both pyrite and quinones, abiotic electron transfer between minerals and organic molecules is likely widespread in Nature and may contribute to several different phenomena, including anaerobic respiration of a wide variety of microorganisms in temporally anoxic zones or in the proximity of hydrothermal vent chimneys, as well as quinone cycling and the propagation of anoxic zones in organic rich waters. Finally, interactions between pyrite and quinones make use of electrochemical gradients that have been suggested as an important source of energy for the origins of life on Earth. Ubiquinones and iron sulfide clusters are common redox cofactors found in electron transport chains across all domains of life and

  10. [Content of mineral elements of Gastrodia elata by principal components analysis].

    PubMed

    Li, Jin-ling; Zhao, Zhi; Liu, Hong-chang; Luo, Chun-li; Huang, Ming-jin; Luo, Fu-lai; Wang, Hua-lei

    2015-03-01

    To study the content of mineral elements and the principal components in Gastrodia elata. Mineral elements were determined by ICP and the data was analyzed by SPSS. K element has the highest content-and the average content was 15.31 g x kg(-1). The average content of N element was 8.99 g x kg(-1), followed by K element. The coefficient of variation of K and N was small, but the Mn was the biggest with 51.39%. The highly significant positive correlation was found among N, P and K . Three principal components were selected by principal components analysis to evaluate the quality of G. elata. P, B, N, K, Cu, Mn, Fe and Mg were the characteristic elements of G. elata. The content of K and N elements was higher and relatively stable. The variation of Mn content was biggest. The quality of G. elata in Guizhou and Yunnan was better from the perspective of mineral elements.

  11. Microbial interspecies electron transfer via electric currents through conductive minerals

    PubMed Central

    Kato, Souichiro; Hashimoto, Kazuhito; Watanabe, Kazuya

    2012-01-01

    In anaerobic biota, reducing equivalents (electrons) are transferred between different species of microbes [interspecies electron transfer (IET)], establishing the basis of cooperative behaviors and community functions. IET mechanisms described so far are based on diffusion of redox chemical species and/or direct contact in cell aggregates. Here, we show another possibility that IET also occurs via electric currents through natural conductive minerals. Our investigation revealed that electrically conductive magnetite nanoparticles facilitated IET from Geobacter sulfurreducens to Thiobacillus denitrificans, accomplishing acetate oxidation coupled to nitrate reduction. This two-species cooperative catabolism also occurred, albeit one order of magnitude slower, in the presence of Fe ions that worked as diffusive redox species. Semiconductive and insulating iron-oxide nanoparticles did not accelerate the cooperative catabolism. Our results suggest that microbes use conductive mineral particles as conduits of electrons, resulting in efficient IET and cooperative catabolism. Furthermore, such natural mineral conduits are considered to provide ecological advantages for users, because their investments in IET can be reduced. Given that conductive minerals are ubiquitously and abundantly present in nature, electric interactions between microbes and conductive minerals may contribute greatly to the coupling of biogeochemical reactions. PMID:22665802

  12. Mineral components and anti-oxidant activities of tropical seaweeds

    NASA Astrophysics Data System (ADS)

    Takeshi, Suzuki; Yumiko, Yoshie-Stark; Joko, Santoso

    2005-07-01

    Seaweeds are known to hold substances of high nutritional value; they are the richest resources of minerals important to the biochemical reactions in the human body. Seaweeds also hold non-nutrient compounds like dietary fiber and polyphenols. However, there is not enough information on the mineral compounds of tropical seaweeds. Also we are interested in the antioxidant activities of seaweeds, especially those in the tropical area. In this study, Indonesian green, brown and red algae were used as experimental materials with their mineral components analyzed by using an atomic absorption spectrophotometer. The catechins and flavonoids of these seaweeds were extracted with methanol and analyzed by high performance liquid chromatography (HPLC); the antioxidant activities of these seaweeds were evaluated in a fish oil emulsion system. The mineral components of tropical seaweeds are dominated by calcium, potassium and sodium, as well as small amounts of copper, iron and zinc. A green alga usually contains epigallocatechin, gallocatechin, epigallocatechin gallate and catechin. However, catechin and its isomers are not found in some green and red algae. In the presence of a ferrous ion catalyst, all the methanol extracts from the seaweeds show significantly lower peroxide values of the emulsion than the control, and that of a green alga shows the strongest antioxidant activity. The highest chelation on ferrous ions is also found in the extract of this alga, which is significantly different from the other methanol extracts in both 3 and 24 h incubations.

  13. Iron-oxide minerals affect extracellular electron-transfer paths of Geobacter spp.

    PubMed

    Kato, Souichiro; Hashimoto, Kazuhito; Watanabe, Kazuya

    2013-01-01

    Some bacteria utilize (semi)conductive iron-oxide minerals as conduits for extracellular electron transfer (EET) to distant, insoluble electron acceptors. A previous study demonstrated that microbe/mineral conductive networks are constructed in soil ecosystems, in which Geobacter spp. share dominant populations. In order to examine how (semi)conductive iron-oxide minerals affect EET paths of Geobacter spp., the present study grew five representative Geobacter strains on electrodes as the sole electron acceptors in the absence or presence of (semi)conductive iron oxides. It was found that iron-oxide minerals enhanced current generation by three Geobacter strains, while no effect was observed in another strain. Geobacter sulfurreducens was the only strain that generated substantial amounts of currents both in the presence and absence of the iron oxides. Microscopic, electrochemical and transcriptomic analyses of G. sulfurreducens disclosed that this strain constructed two distinct types of EET path; in the absence of iron-oxide minerals, bacterial biofilms rich in extracellular polymeric substances were constructed, while composite networks made of mineral particles and microbial cells (without polymeric substances) were developed in the presence of iron oxides. It was also found that uncharacterized c-type cytochromes were up-regulated in the presence of iron oxides that were different from those found in conductive biofilms. These results suggest the possibility that natural (semi)conductive minerals confer energetic and ecological advantages on Geobacter, facilitating their growth and survival in the natural environment.

  14. Bacteriostatic conformal coating for electronic components

    NASA Technical Reports Server (NTRS)

    Bland, C.; Le Doux, F. N.

    1967-01-01

    Coating for electronic components used in space applications has bacteriostatic qualities capable of hindering bacterial reproduction, both vegetative and sporulative viable microorganisms. It exhibits high electrical resistivity, a low outgassing rate, and is capable of restraining electronic components when subjected to mechanical vibrations.

  15. The nature of the mineral component of bone and the mechanism of calcification.

    PubMed

    Glimcher, M J

    1987-01-01

    From the physical chemical standpoint, the formation of a solid phase of Ca-P in bone represents a phase transformation, a process exemplified by the formation of ice from water. Considering the structural complexity and abundance of highly organized macromolecules in the cells and extracellular tissue spaces of mineralized tissues generally and in bone particularly, it is inconceivable that this phase transformation occurs by homogeneous nucleation, i.e., without the active participation of an organic component acting as a nucleator. This is almost surely true in biologic mineralization in general. Electron micrographs and low-angle neutron and X-ray diffraction studies clearly show that calcification of collagen fibrils occurs in an extremely intimate and highly organized fashion: initiation of crystal formation within the collagen fibrils in the hole zone region, with the long axes (c-axis) of the crystals aligned roughly parallel to the long axis of the fibril within which they are located. Crystals are initially formed in hole zone regions within individual fibrils separated by unmineralized regions. Calcification is initiated in spatially distinct nucleation sites. This indicates that such regions within a single, undirectional fibril represents independent sites for heterogeneous nucleation. Clearly, sites where mineralization is initiated in adjacent collagen fibrils are even further separated, emphasizing even more clearly that the process of progressive calcification of the collagen fibrils and therefore of the tissue is characterized principally by the presence of increasing numbers of independent nucleation sites within additional hole zone regions of the collagen fibrils. The increase in the mass of Ca-P apatite accrues principally by multiplication of more crystals, mostly by secondary nucleation from the crystals initially deposited in the hole zone region. Very little additional growth of the crystals occurs with time, the additional increase in

  16. A world of minerals in your mobile device

    USGS Publications Warehouse

    Jenness, Jane E.; Ober, Joyce A.; Wilkins, Aleeza M.; Gambogi, Joseph

    2016-09-15

    Mobile phones and other high-technology communications devices could not exist without mineral commodities. More than one-half of all components in a mobile device—including its electronics, display, battery, speakers, and more—are made from mined and semiprocessed materials (mineral commodities). Some mineral commodities can be recovered as byproducts during the production and processing of other commodities. As an example, bauxite is mined for its aluminum content, but gallium is recovered during the aluminum production process. The images show the ore minerals (sources) of some mineral commodities that are used to make components of a mobile device. On the reverse side, the map and table depict the major source countries producing these mineral commodities along with how these commodities are used in mobile devices. For more information on minerals, visit http://minerals.usgs.gov.

  17. 7 CFR 3201.80 - Electronic components cleaners.

    Code of Federal Regulations, 2013 CFR

    2013-01-01

    ... PROCUREMENT Designated Items § 3201.80 Electronic components cleaners. (a) Definition. Products that are designed to wash or remove dirt or extraneous matter from electronic parts, devices, circuits, or systems... 7 Agriculture 15 2013-01-01 2013-01-01 false Electronic components cleaners. 3201.80 Section 3201...

  18. 7 CFR 3201.80 - Electronic components cleaners.

    Code of Federal Regulations, 2014 CFR

    2014-01-01

    ... PROCUREMENT Designated Items § 3201.80 Electronic components cleaners. (a) Definition. Products that are designed to wash or remove dirt or extraneous matter from electronic parts, devices, circuits, or systems... 7 Agriculture 15 2014-01-01 2014-01-01 false Electronic components cleaners. 3201.80 Section 3201...

  19. Electron acoustic-Langmuir solitons in a two-component electron plasma

    NASA Astrophysics Data System (ADS)

    McKenzie, J. F.

    2003-04-01

    We investigate the conditions under which ‘high-frequency’ electron acoustic Langmuir solitons can be constructed in a plasma consisting of protons and two electron populations: one ‘cold’ and the other ‘hot’. Conservation of total momentum can be cast as a structure equation either for the ‘cold’ or ‘hot’ electron flow speed in a stationary wave using the Bernoulli energy equations for each species. The linearized version of the governing equations gives the dispersion equation for the stationary waves of the system, from which follows the necessary but not sufficient conditions for the existence of soliton structures; namely that the wave speed must be less than the acoustic speed of the ‘hot’ electron component and greater than the low-frequency compound acoustic speed of the two electron populations. In this wave speed regime linear waves are ‘evanescent’, giving rise to the exponential growth or decay, which readily can give rise to non-linear effects that may balance dispersion and allow soliton formation. In general the ‘hot’ component must be more abundant than the ‘cold’ one and the wave is characterized by a compression of the ‘cold’ component and an expansion in the ‘hot’ component necessitating a potential dip. Both components are driven towards their sonic points; the ‘cold’ from above and the ‘hot’ from below. It is this transonic feature which limits the amplitude of the soliton. If the ‘hot’ component is not sufficiently abundant the window for soliton formation shrinks to a narrow speed regime which is quasi-transonic relative to the ‘hot’ electron acoustic speed, and it is shown that smooth solitons cannot be constructed. In the special case of a very cold electron population (i.e. ‘highly supersonic’) and the other population being very hot (i.e. ‘highly subsonic’) with adiabatic index 2, the structure equation simplifies and can be integrated in terms of elementary

  20. Tibial component coverage based on bone mineral density of the cut tibial surface during unicompartmental knee arthroplasty: clinical relevance of the prevention of tibial component subsidence.

    PubMed

    Lee, Yong Seuk; Yun, Ji Young; Lee, Beom Koo

    2014-01-01

    An optimally implanted tibial component during unicompartmental knee arthroplasty would be flush with all edges of the cut tibial surface. However, this is often not possible, partly because the tibial component may not be an ideal shape or because the ideal component size may not be available. In such situations, surgeons need to decide between component overhang and underhang and as to which sites must be covered and which sites could be undercovered. The objectives of this study were to evaluate the bone mineral density of the cut surface of the proximal tibia around the cortical rim and to compare the bone mineral density according to the inclusion of the cortex and the site-specific matched evaluation. One hundred and fifty consecutive patients (100 men and 50 women) were enrolled in this study. A quantitative computed tomography was used to determine the bone density of the cut tibial surface. Medial and lateral compartments were divided into anterior, middle, and posterior regions, and these three regions were further subdivided into two regions according to containment of cortex. The site-specific matched comparison (medial vs. lateral) of bone mineral density was performed. In medial sides, the mid-region, including the cortex, showed the highest bone mineral density in male and female patients. The posterior region showed the lowest bone mineral density in male patients, and the anterior and posterior regions showed the lowest bone mineral density in female patients. Regions including cortex showed higher bone mineral density than pure cancellous regions in medial sides. In lateral sides, posterior regions including cortex showed highest bone mineral density with statistical significance in both male and female patients. The anterior region showed the lowest bone mineral density in both male and female patients. The mid-region of the medial side and the posterior region of the lateral side are relatively safe without cortical coverage when the component

  1. The enabling technology for recovery of valued components from minerals in the upper and Mid Amur region

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Sorokin, A.P.; Rimkevich, V.S.; Dem'yanova, L.P.

    2009-05-15

    Based on the physico-technical operations involved in the mineral processing technologies, the optimal production conditions are found for refractory fiber materials, aluminium, silicium, their compounds and other valued components. Ecologically safe and efficient aggregate technologies are developed for recovery of valued components from nonmetallic minerals and anthracides (brown coals).

  2. Towards Prognostics for Electronics Components

    NASA Technical Reports Server (NTRS)

    Saha, Bhaskar; Celaya, Jose R.; Wysocki, Philip F.; Goebel, Kai F.

    2013-01-01

    Electronics components have an increasingly critical role in avionics systems and in the development of future aircraft systems. Prognostics of such components is becoming a very important research field as a result of the need to provide aircraft systems with system level health management information. This paper focuses on a prognostics application for electronics components within avionics systems, and in particular its application to an Isolated Gate Bipolar Transistor (IGBT). This application utilizes the remaining useful life prediction, accomplished by employing the particle filter framework, leveraging data from accelerated aging tests on IGBTs. These tests induced thermal-electrical overstresses by applying thermal cycling to the IGBT devices. In-situ state monitoring, including measurements of steady-state voltages and currents, electrical transients, and thermal transients are recorded and used as potential precursors of failure.

  3. 21 CFR 11.200 - Electronic signature components and controls.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ... 21 Food and Drugs 1 2010-04-01 2010-04-01 false Electronic signature components and controls. 11... SERVICES GENERAL ELECTRONIC RECORDS; ELECTRONIC SIGNATURES Electronic Signatures § 11.200 Electronic signature components and controls. (a) Electronic signatures that are not based upon biometrics shall: (1...

  4. Multilayer electronic component systems and methods of manufacture

    NASA Technical Reports Server (NTRS)

    Thompson, Dane (Inventor); Wang, Guoan (Inventor); Kingsley, Nickolas D. (Inventor); Papapolymerou, Ioannis (Inventor); Tentzeris, Emmanouil M. (Inventor); Bairavasubramanian, Ramanan (Inventor); DeJean, Gerald (Inventor); Li, RongLin (Inventor)

    2010-01-01

    Multilayer electronic component systems and methods of manufacture are provided. In this regard, an exemplary system comprises a first layer of liquid crystal polymer (LCP), first electronic components supported by the first layer, and a second layer of LCP. The first layer is attached to the second layer by thermal bonds. Additionally, at least a portion of the first electronic components are located between the first layer and the second layer.

  5. Electronic Components Subsystems and Equipment: a Compilation

    NASA Technical Reports Server (NTRS)

    1975-01-01

    Developments in electronic components, subsystems, and equipment are summarized. Topics discussed include integrated circuit components and techniques, circuit components and techniques, and cables and connectors.

  6. Minerals and aligned collagen fibrils in tilapia fish scales: structural analysis using dark-field and energy-filtered transmission electron microscopy and electron tomography.

    PubMed

    Okuda, Mitsuhiro; Ogawa, Nobuhiro; Takeguchi, Masaki; Hashimoto, Ayako; Tagaya, Motohiro; Chen, Song; Hanagata, Nobutaka; Ikoma, Toshiyuki

    2011-10-01

    The mineralized structure of aligned collagen fibrils in a tilapia fish scale was investigated using transmission electron microscopy (TEM) techniques after a thin sample was prepared using aqueous techniques. Electron diffraction and electron energy loss spectroscopy data indicated that a mineralized internal layer consisting of aligned collagen fibrils contains hydroxyapatite crystals. Bright-field imaging, dark-field imaging, and energy-filtered TEM showed that the hydroxyapatite was mainly distributed in the hole zones of the aligned collagen fibrils structure, while needle-like materials composed of calcium compounds including hydroxyapatite existed in the mineralized internal layer. Dark-field imaging and three-dimensional observation using electron tomography revealed that hydroxyapatite and needle-like materials were mainly found in the matrix between the collagen fibrils. It was observed that hydroxyapatite and needle-like materials were preferentially distributed on the surface of the hole zones in the aligned collagen fibrils structure and in the matrix between the collagen fibrils in the mineralized internal layer of the scale.

  7. Sensory evaluation and electronic tongue for sensing flavored mineral water taste attributes.

    PubMed

    Sipos, László; Gere, Attila; Szöllősi, Dániel; Kovács, Zoltán; Kókai, Zoltán; Fekete, András

    2013-10-01

    In this article a trained sensory panel evaluated 6 flavored mineral water samples. The samples consisted of 3 different brands, each with 2 flavors (pear-lemon grass and josta berry). The applied sensory method was profile analysis. Our aim was to analyze the sensory profiles and to investigate the similarities between the sensitivity of the trained human panel and an electronic tongue device. Another objective was to demonstrate the possibilities for the prediction of sensory attributes from electronic tongue measurements using a multivariate statistical method (Partial Least Squares regression [PLS]). The results showed that the products manufactured under different brand name but with the same aromas had very similar sensory profiles. The panel performance evaluation showed that it is appropriate (discrimination ability, repeatability, and panel consensus) to compare the panel's results with the results of the electronic tongue. The samples can be discriminated by the electronic tongue and an accurate classification model can be built. Principal Component Analysis BiPlot diagrams showed that Brand A and B were similar because the manufacturers use the same aroma brands for their products. It can be concluded that Brand C was quite different compared to the other samples independently of the aroma content. Based on the electronic tongue results good prediction models can be obtained with high correlation coefficient (r(2) > 0.81) and low prediction error (RMSEP < 13.71 on the scale of the sensory evaluation from 0 to 100). © 2013 Institute of Food Technologists®

  8. Electron Transport at the Microbe–Mineral Interface: A Synthesis of Current Research Challenges

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Richardson, David; Fredrickson, Jim K.; Zachara, John M.

    2012-12-01

    Many bacterial and archaeal species can couple growth to the respiratory reduction or oxidation of insoluble mineral oxides of transition metals. These solid substrates are abundant electron sinks and sources for life on Earth, but, since they are insoluble in water, they cannot enter the bacterial cells. So, to exploit these electron sinks and sources, specific respiratory electron-transfer mechanisms must overcome the physical limitations associated with electron transfer between a microbe and extracellular metal oxides. Recent microbiological, geochemical, biochemical, spectroscopic and structural work is beginning to shed light on the molecular mechanism and impacts of electron transfer at themicrobe–mineral interfacemore » from a nanometre to kilometre scale. The research field is attracting attention in applied quarters from those with interests in nanowires, microbial fuel cells, bioremediation and microbial cell factories.« less

  9. Electron Microprobe Analyses of Lithic Fragments and Their Minerals from Luna 20 Fines

    NASA Technical Reports Server (NTRS)

    Conrad, G. H.; Hlava, P. F.; Green, J. A.; Moore, R. B.; Moreland, G.; Dowty, E.; Prinz, M.; Keil, K.; Nehru, C. E.; Bunch, T. E.

    1973-01-01

    The bulk analyses (determined with the broad beam electron microprobe technique) of lithic fragments are given in weight percentages and are arranged according to the rock classification. Within each rock group the analyses are arranged in order of increasing FeO content. Thin section and lithic fragment numbers are given at the top of each column of analysis and correspond to the numbers recorded on photo mosaics on file in the Institute of Meteoritics. CIPW molecular norms are given for each analysis. Electron microprobe mineral analyses (given in oxide weight percentages), structural formulae and molecular end member values are presented for plagioclase, olivine, pyroxene and K-feldspar. The minerals are selected mostly from lithic fragments that were also analyzed for bulk composition. Within each mineral group the analyses are presented according to the section number and lithic fragment number. Within each lithic fragment the mineral analyses are arranged as follows: Plagioclase in order of increasing CaO; olivine and pyroexene in order of increasing FeO; and K-feldspar in order of increasing K2O. The mineral grains are identified at the top of each column of analysis by grain number and lithic fragment number.

  10. Electronic warfare microwave components

    NASA Astrophysics Data System (ADS)

    Cosby, L. A.

    1984-09-01

    The current and projected state-of-the-art for electronic warfare (EW) microwave components is reviewed, with attention given to microwave components used extensively in EW systems for reconnaissance, threat warning, direction finding, and repeater jamming. It is emphasized that distributed EW systems must be able to operate from manned tactical and strategic platforms, with requirements including remote aerospace and space elements, as well as the need for expandable devices for detection, location, and denial/deception functions. EW coordination, or battle management, across a distributed system is a rapidly emerging requirement that must be integrated into current and projected command-and-control programs.

  11. Rapid electron exchange between surface-exposed bacterial cytochromes and Fe(III) minerals

    PubMed Central

    White, Gaye F.; Shi, Zhi; Shi, Liang; Wang, Zheming; Dohnalkova, Alice C.; Marshall, Matthew J.; Fredrickson, James K.; Zachara, John M.; Butt, Julea N.; Richardson, David J.; Clarke, Thomas A.

    2013-01-01

    The mineral-respiring bacterium Shewanella oneidensis uses a protein complex, MtrCAB, composed of two decaheme cytochromes, MtrC and MtrA, brought together inside a transmembrane porin, MtrB, to transport electrons across the outer membrane to a variety of mineral-based electron acceptors. A proteoliposome system containing a pool of internalized electron carriers was used to investigate how the topology of the MtrCAB complex relates to its ability to transport electrons across a lipid bilayer to externally located Fe(III) oxides. With MtrA facing the interior and MtrC exposed on the outer surface of the phospholipid bilayer, the established in vivo orientation, electron transfer from the interior electron carrier pool through MtrCAB to solid-phase Fe(III) oxides was demonstrated. The rates were 103 times higher than those reported for reduction of goethite, hematite, and lepidocrocite by S. oneidensis, and the order of the reaction rates was consistent with those observed in S. oneidensis cultures. In contrast, established rates for single turnover reactions between purified MtrC and Fe(III) oxides were 103 times lower. By providing a continuous flow of electrons, the proteoliposome experiments demonstrate that conduction through MtrCAB directly to Fe(III) oxides is sufficient to support in vivo, anaerobic, solid-phase iron respiration. PMID:23538304

  12. [Spatial heterogeneity of surface soil mineral components in a small catchment in Karst peak-cluster depression area, South China].

    PubMed

    Gao, Peng; Fu, Tong-Gang; Wang, Ke-Lin; Chen, Hong-Song; Zeng, Fu-Ping

    2013-11-01

    A total of 163 soil samples (0-20 cm layer) were collected from the grid sampling plots (80 m x 80 m) in Huanjiang Observation and Research Station of Karst Ecosystem in a small catchment in Karst cluster-peak depression area, South China. By using classical statistics and geostatistics, the spatial heterogeneity of mineral components (SiO2, Fe2O3, CaO, MgO, Al2O3, MnO, and TiO2) in the soils were studied. The contents of the seven soil mineral components in the study area differed greatly, being in the order of SiO2 > Al2O3 > CaO > MgO > Fe2O3 > TiO2 > MnO, and the variance coefficients also varied obviously, in the order of CaO > MgO > Fe2O3 > TiO2 > SiO2 > Al2O3 > MnO. The seven mineral components accounted for 69.4% of the total soil mass. The spatial patterns and the fittest models of the seven soil mineral components differed from each other. All the seven soil mineral components had a strong spatial autocorrelation, with shorter variation ranges and stronger spatial dependence. The Kriging contour maps indicated that the distribution patterns of soil SiO2, Fe2O3, Al2O3, MnO, and TiO2 were similar, being higher in south and east, lower in north and west, higher in depression, and lower in slope, while the distribution patterns of soil CaO and MgO were in adverse. Natural conditions (vegetation, bare rock rate, slope degree, and slope aspect, etc. ) and human disturbance were the most important factors affecting the spatial patterns of the soil mineral components.

  13. Core level electron energy-loss spectra of minerals: pre-edge fine structures at the oxygen K-edge . Comment on ``Water in minerals detectable by electron energy-loss spectroscopy EELS'' by R. Wirth, Phys Chem Minerals (1997) 24:561-568

    NASA Astrophysics Data System (ADS)

    van Aken, P. A.; Liebscher, B.; Styrsa, V. J.

    In a recent paper entitled ``Water in minerals detectable by electron energy-loss spectroscopy EELS'' by R. Wirth, it has been claimed that OH-- and H2O-bearing minerals exhibit a characteristic peak in the ELNES spectra at about 528 eV prior to the onset of the O K-edge at 532 eV, which could be used for (semi-)quantitative determination of water- or OH-contents on a nanometer scale. It is shown here by parallel electron energy-loss spectroscopy (PEELS) recorded in a transmission electron microscope (TEM) that O K-pre-edge peaks with very high intensities may also exist in water-free compounds and minerals, in particular when they contain transition metals. These spectral features arise from covalent mixing of the metal and oxygen states, which introduces oxygen p character in unoccupied states of mainly metal character. The point is illustrated by the comparison of hematite (α-Fe2O3) and lepidocrocite (γ-FeOOH) O K-edge PEELS spectra which exhibit similar intensities of the pre-edge peak, despite of their grossly different OH- contents. As a consequence, the general validity of the method proposed by Wirth is questioned.

  14. Scanning electron microscopy of clays and clay minerals

    USGS Publications Warehouse

    Bohor, B.F.; Hughes, R.E.

    1971-01-01

    The scanning electron microscope (SEM) proves to be ideally suited for studying the configuration, texture, and fabric of clay samples. Growth mechanics of crystalline units—interpenetration and interlocking of crystallites, crystal habits, twinning, helical growth, and topotaxis—also are uniquely revealed by the SEM.Authigenic kaolins make up the bulk of the examples because their larger crystallite size, better crystallinity, and open texture make them more suited to examination by the SEM than most other clay mineral types.

  15. Terrestrial and Martian weathering signatures of xenon components in shergottite mineral separates

    NASA Astrophysics Data System (ADS)

    Cartwright, J. A.; Ocker, K. D.; Crowther, S. A.; Burgess, R.; Gilmour, J. D.

    2010-08-01

    Xenon-isotopic ratios, step-heating release patterns, and gas concentrations of mineral separates from Martian shergottites Roberts Massif (RBT) 04262, Dar al Gani (DaG) 489, Shergotty, and Elephant Moraine (EET) 79001 lithology B are reported. Concentrations of Martian atmospheric xenon are similar in mineral separates from all meteorites, but more weathered samples contain more terrestrial atmospheric xenon. The distributions of xenon from the Martian and terrestrial atmospheres among minerals in any one sample are similar, suggesting similarities in the processes by which they were acquired. However, in opaque and maskelynite fractions, Martian atmospheric xenon is released at higher temperatures than terrestrial atmospheric xenon. It is suggested that both Martian and terrestrial atmospheric xenon were initially introduced by weathering (low temperature alteration processes). However, the Martian component was redistributed by shock, accounting for its current residence in more retentive sites. The presence or absence of detectable 129Xe from the Martian atmosphere in mafic minerals may correspond to the extent of crustal contamination of the rock's parent melt. Variable contents of excess 129Xe contrast with previously reported consistent concentrations of excess 40Ar, suggesting distinct sources contributed these gases to the parent magma.

  16. Optical-electronic system for express analysis of mineral raw materials dressability by color sorting method

    NASA Astrophysics Data System (ADS)

    Alekhin, Artem A.; Gorbunova, Elena V.; Chertov, Aleksandr N.; Petuhova, Darya B.

    2013-04-01

    Due to the depletion of solid minerals ore reserves and the involvement in the production of the poor and refractory ores a process of continuous appreciation of minerals is going. In present time at the market of enrichment equipment are well represented optical sorters of various firms. All these sorters are essentially different from each other by parameters of productivity, classes of particles sizes for processed raw, nuances of decision algorithm, as well as by color model (RGB, YUV, HSB, etc.) chosen to describe the color of separating mineral samples. At the same time there is no dressability estimation method for mineral raw materials without direct semi-industrial test on the existing type of optical sorter, as well as there is no equipment realizing mentioned dressability estimation method. It should also be note the lack of criteria for choosing of one or another manufacturer (or type) of optical sorter. A direct consequence of this situation is the "opacity" of the color sorting method and the rejection of its potential customers. The proposed solution of mentioned problems is to develop the dressability estimation method, and to create an optical-electronic system for express analysis of mineral raw materials dressability by color sorting method. This paper has the description of structure organization and operating principles of experimental model optical-electronic system for express analysis of mineral raw material. Also in this work are represented comparison results of the proposed optical-electronic system and the real color sorter.

  17. Screen printed passive components for flexible power electronics.

    PubMed

    Ostfeld, Aminy E; Deckman, Igal; Gaikwad, Abhinav M; Lochner, Claire M; Arias, Ana C

    2015-10-30

    Additive and low-temperature printing processes enable the integration of diverse electronic devices, both power-supplying and power-consuming, on flexible substrates at low cost. Production of a complete electronic system from these devices, however, often requires power electronics to convert between the various operating voltages of the devices. Passive components-inductors, capacitors, and resistors-perform functions such as filtering, short-term energy storage, and voltage measurement, which are vital in power electronics and many other applications. In this paper, we present screen-printed inductors, capacitors, resistors and an RLC circuit on flexible plastic substrates, and report on the design process for minimization of inductor series resistance that enables their use in power electronics. Printed inductors and resistors are then incorporated into a step-up voltage regulator circuit. Organic light-emitting diodes and a flexible lithium ion battery are fabricated and the voltage regulator is used to power the diodes from the battery, demonstrating the potential of printed passive components to replace conventional surface-mount components in a DC-DC converter application.

  18. Potting procedure for electronic components

    NASA Technical Reports Server (NTRS)

    Rubino, A. G.; Zimmerman, J.

    1977-01-01

    Potting process is modified to effect a match more closely between embedded electronic components, potting mediums, and thermal environment. Application of room-temperature vulcanizing silicone rubber band cured in modified thermal cycle minimizes coil-to-resin adhesion and thus lowers stresses between transformer and potting compound.

  19. Investigating Microbe-Mineral Interactions: Recent Advances in X-Ray and Electron Microscopy and Redox-Sensitive Methods

    NASA Astrophysics Data System (ADS)

    Miot, Jennyfer; Benzerara, Karim; Kappler, Andreas

    2014-05-01

    Microbe-mineral interactions occur in diverse modern environments, from the deep sea and subsurface rocks to soils and surface aquatic environments. They may have played a central role in the geochemical cycling of major (e.g., C, Fe, Ca, Mn, S, P) and trace (e.g., Ni, Mo, As, Cr) elements over Earth's history. Such interactions include electron transfer at the microbe-mineral interface that left traces in the rock record. Geomicrobiology consists in studying interactions at these organic-mineral interfaces in modern samples and looking for traces of past microbe-mineral interactions recorded in ancient rocks. Specific tools are required to probe these interfaces and to understand the mechanisms of interaction between microbes and minerals from the scale of the biofilm to the nanometer scale. In this review, we focus on recent advances in electron microscopy, in particular in cryoelectron microscopy, and on a panel of electrochemical and synchrotron-based methods that have recently provided new understanding and imaging of the microbe-mineral interface, ultimately opening new fields to be explored.

  20. Recent Progress on Stretchable Electronic Devices with Intrinsically Stretchable Components.

    PubMed

    Trung, Tran Quang; Lee, Nae-Eung

    2017-01-01

    Stretchable electronic devices with intrinsically stretchable components have significant inherent advantages, including simple fabrication processes, a high integrity of the stacked layers, and low cost in comparison with stretchable electronic devices based on non-stretchable components. The research in this field has focused on developing new intrinsically stretchable components for conductors, semiconductors, and insulators. New methodologies and fabrication processes have been developed to fabricate stretchable devices with intrinsically stretchable components. The latest successful examples of stretchable conductors for applications in interconnections, electrodes, and piezoresistive devices are reviewed here. Stretchable conductors can be used for electrode or sensor applications depending on the electrical properties of the stretchable conductors under mechanical strain. A detailed overview of the recent progress in stretchable semiconductors, stretchable insulators, and other novel stretchable materials is also given, along with a discussion of the associated technological innovations and challenges. Stretchable electronic devices with intrinsically stretchable components such as field-effect transistors (FETs), photodetectors, light-emitting diodes (LEDs), electronic skins, and energy harvesters are also described and a new strategy for development of stretchable electronic devices is discussed. Conclusions and future prospects for the development of stretchable electronic devices with intrinsically stretchable components are discussed. © 2016 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  1. Prognostics for Electronics Components of Avionics Systems

    NASA Technical Reports Server (NTRS)

    Celaya, Jose R.; Saha, Bhaskar; Wysocki, Philip F.; Goebel, Kai F.

    2009-01-01

    Electronics components have and increasingly critical role in avionics systems and for the development of future aircraft systems. Prognostics of such components is becoming a very important research filed as a result of the need to provide aircraft systems with system level health management. This paper reports on a prognostics application for electronics components of avionics systems, in particular, its application to the Isolated Gate Bipolar Transistor (IGBT). The remaining useful life prediction for the IGBT is based on the particle filter framework, leveraging data from an accelerated aging tests on IGBTs. The accelerated aging test provided thermal-electrical overstress by applying thermal cycling to the device. In-situ state monitoring, including measurements of the steady-state voltages and currents, electrical transients, and thermal transients are recorded and used as potential precursors of failure.

  2. An automatic chip structure optical inspection system for electronic components

    NASA Astrophysics Data System (ADS)

    Song, Zhichao; Xue, Bindang; Liang, Jiyuan; Wang, Ke; Chen, Junzhang; Liu, Yunhe

    2018-01-01

    An automatic chip structure inspection system based on machine vision is presented to ensure the reliability of electronic components. It consists of four major modules, including a metallographic microscope, a Gigabit Ethernet high-resolution camera, a control system and a high performance computer. An auto-focusing technique is presented to solve the problem that the chip surface is not on the same focusing surface under the high magnification of the microscope. A panoramic high-resolution image stitching algorithm is adopted to deal with the contradiction between resolution and field of view, caused by different sizes of electronic components. In addition, we establish a database to storage and callback appropriate parameters to ensure the consistency of chip images of electronic components with the same model. We use image change detection technology to realize the detection of chip images of electronic components. The system can achieve high-resolution imaging for chips of electronic components with various sizes, and clearly imaging for the surface of chip with different horizontal and standardized imaging for ones with the same model, and can recognize chip defects.

  3. Cryogenic applications of commercial electronic components

    NASA Astrophysics Data System (ADS)

    Buchanan, Ernest D.; Benford, Dominic J.; Forgione, Joshua B.; Harvey Moseley, S.; Wollack, Edward J.

    2012-10-01

    We have developed a range of techniques useful for constructing analog and digital circuits for operation in a liquid Helium environment (4.2 K), using commercially available low power components. The challenges encountered in designing cryogenic electronics include finding components that can function usefully in the cold and possess low enough power dissipation so as not to heat the systems they are designed to measure. From design, test, and integration perspectives it is useful for components to operate similarly at room and cryogenic temperatures; however this is not a necessity. Some of the circuits presented here have been used successfully in the MUSTANG [1] and in the GISMO [2] camera to build a complete digital to analog multiplexer (which will be referred to as the Cryogenic Address Driver board). Many of the circuit elements described are of a more general nature rather than specific to the Cryogenic Address Driver board, and were studied as a part of a more comprehensive approach to addressing a larger set of cryogenic electronic needs.

  4. Cryogenic Applications of Commercial Electronic Components

    NASA Technical Reports Server (NTRS)

    Buchanan, Ernest D.; Benford, Dominic J.; Forgione, Joshua B.; Moseley, S. Harvey; Wollack, Edward J.

    2012-01-01

    We have developed a range of techniques useful for constructing analog and digital circuits for operation in a liquid Helium environment (4.2K), using commercially available low power components. The challenges encountered in designing cryogenic electronics include finding components that can function usefully in the cold and possess low enough power dissipation so as not to heat the systems they are designed to measure. From design, test, and integration perspectives it is useful for components to operate similarly at room and cryogenic temperatures; however this is not a necessity. Some of the circuits presented here have been used successfully in the MUSTANG and in the GISMO camera to build a complete digital to analog multiplexer (which will be referred to as the Cryogenic Address Driver board). Many of the circuit elements described are of a more general nature rather than specific to the Cryogenic Address Driver board, and were studied as a part of a more comprehensive approach to addressing a larger set of cryogenic electronic needs.

  5. Mineral content changes in bone associated with damage induced by the electron beam.

    PubMed

    Bloebaum, Roy D; Holmes, Jennifer L; Skedros, John G

    2005-01-01

    Energy-dispersive x-ray (EDX) spectroscopy and backscattered electron (BSE) imaging are finding increased use for determining mineral content in microscopic regions of bone. Electron beam bombardment, however, can damage the tissue, leading to erroneous interpretations of mineral content. We performed elemental (EDX) and mineral content (BSE) analyses on bone tissue in order to quantify observable deleterious effects in the context of (1) prolonged scanning time, (2) scan versus point (spot) mode, (3) low versus high magnification, and (4) embedding in poly-methylmethacrylate (PMMA). Undemineralized cortical bone specimens from adult human femora were examined in three groups: 200x embedded, 200x unembedded, and 1000x embedded. Coupled BSE/EDX analyses were conducted five consecutive times, with no location analyzed more than five times. Variation in the relative proportions of calcium (Ca), phosphorous (P), and carbon (C) were measured using EDX spectroscopy, and mineral content variations were inferred from changes in mean gray levels ("atomic number contrast") in BSE images captured at 20 keV. In point mode at 200x, the embedded specimens exhibited a significant increase in Ca by the second measurement (7.2%, p < 0.05); in scan mode, a small and statistically nonsignificant increase (1.0%) was seen by the second measurement. Changes in P were similar, although the increases were less. The apparent increases in Ca and P likely result from decreases in C: -3.2% (p < 0.05) in point mode and -0.3% in scan mode by the second measurement. Analysis of unembedded specimens showed similar results. In contrast to embedded specimens at 200x, 1000x data showed significantly larger variations in the proportions of Ca, P, and C by the second or third measurement in scan and point mode. At both magnifications, BSE image gray level values increased (suggesting increased mineral content) by the second measurement, with increases up to 23% in point mode. These results show that

  6. Investigation of Mineral Transformations in Wet Supercritical CO2 by Electron Microscopy

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Arey, Bruce W.; Kovarik, Libor; Wang, Zheming

    2011-10-10

    The capture and storage of carbon dioxide and other greenhouse gases in deep geologic formations represents one of the most promising options for mitigating the impacts of greenhouse gases on global warming. In this regard, mineral-fluid interactions are of prime importance since such reactions can result in the long term sequestration of CO2 by trapping in mineral phases. Recently it has been recognized that interactions with neat to water-saturated non-aqueous fluids are of prime importance in understanding mineralization reactions since the introduced CO2 is likely to contain water initially or soon after injection and the supercritical CO2 (scCO2) is lessmore » dense than the aqueous phase which can result in a buoyant scCO2 plume contacting the isolating caprock. As a result, unraveling the molecular/microscopic mechanisms of mineral transformation in neat to water saturated scCO2 has taken on an added important. In this study, we are examining the interfacial reactions of the olivine mineral forsterite (Mg2SiO4) over a range of water contents up to and including complete water saturation in scCO2. The surface precipitates that form on the reacted forsterite grains are extremely fragile and difficult to experimentally characterize. In order to address this issue we have developed experimental protocols for preparing and imaging electron-transparent samples from fragile structures. These electron-transparent samples are then examined using a combination of STEM/EDX, FIB-TEM, and helium ion microscope (HIM) imaging (Figures 1-3). This combination of capabilities has provided unique insight into the geochemical processes that occur on scCO2 reacted mineral surfaces. The experimental procedures and protocols that have been developed also have useful applications for examining fragile structures on a wide variety of materials. This research was performed using EMSL, a national scientific user facility sponsored by the Department of Energy's Office of Biological

  7. Bacterial entombment by intratubular mineralization following orthograde mineral trioxide aggregate obturation: a scanning electron microscopy study

    PubMed Central

    Yoo, Jun Sang; Chang, Seok-Woo; Oh, So Ram; Perinpanayagam, Hiran; Lim, Sang-Min; Yoo, Yeon-Jee; Oh, Yeo-Rok; Woo, Sang-Bin; Han, Seung-Hyun; Zhu, Qiang; Kum, Kee-Yeon

    2014-01-01

    The time domain entombment of bacteria by intratubular mineralization following orthograde canal obturation with mineral trioxide aggregate (MTA) was studied by scanning electron microscopy (SEM). Single-rooted human premolars (n=60) were instrumented to an apical size #50/0.06 using ProFile and treated as follows: Group 1 (n=10) was filled with phosphate buffered saline (PBS); Group 2 (n=10) was incubated with Enterococcus faecalis for 3 weeks, and then filled with PBS; Group 3 (n=20) was obturated orthograde with a paste of OrthoMTA (BioMTA, Seoul, Korea) and PBS; and Group 4 (n=20) was incubated with E. faecalis for 3 weeks and then obturated with OrthoMTA–PBS paste. Following their treatments, the coronal openings were sealed with PBS-soaked cotton and intermediate restorative material (IRM), and the roots were then stored in PBS for 1, 2, 4, 8 or 16 weeks. After each incubation period, the roots were split and their dentin/MTA interfaces examined in both longitudinal and horizontal directions by SEM. There appeared to be an increase in intratubular mineralization over time in the OrthoMTA-filled roots (Groups 3 and 4). Furthermore, there was a gradual entombment of bacteria within the dentinal tubules in the E. faecalis inoculated MTA-filled roots (Group 4). Therefore, the orthograde obturation of root canals with OrthoMTA mixed with PBS may create a favorable environment for bacterial entombment by intratubular mineralization. PMID:25012869

  8. Current Space Station Experiments Investigating Component Level Electronics Repair

    NASA Technical Reports Server (NTRS)

    Easton, John W.; Struk, Peter M.

    2010-01-01

    The Soldering in a Reduced Gravity Experiment (SoRGE) and Component Repair Experiment (CRE)-1 are tests performed on the International Space Station to determine the techniques, tools, and training necessary to allow future crews to perform manual electronics repairs at the component level. SoRGE provides information on the formation and internal structure of through-hole solder joints, illustrating the challenges and implications of soldering in reduced gravity. SoRGE showed a significant increase in internal void defects for joints formed in low gravity compared to normal gravity. Methods for mitigating these void defects were evaluated using a modified soldering process. CRE-1 demonstrated the removal, cleaning, and replacement of electronics components by manual means on functional circuit boards. The majority of components successful passed a post-repair functional test demonstrating the feasibility of component-level repair within the confines of a spacecraft. Together, these tasks provide information to recommend material and tool improvements, training improvements, and future work to help enable electronics repairs in future space missions.

  9. State of the mineral component of rat bone tissue during hypokinesia and the recovery period

    NASA Technical Reports Server (NTRS)

    Volozhin, A. I.; Stupakov, G. P.; Pavlova, M. N.; Muradov, I. S.

    1980-01-01

    Experiments were conducted on young growing rats. Hypokinesia lasting from 20 to 200 days caused retarded gain in weight and volume of the femur and delayed development of the cortical layer of the diaphysis. In contrast, the density of the cortical layer of the femoral diaphysis increased due to elevation of the mineral saturation of the bone tissue microstructures. Incorporation of Ca into the bone tissue in hypokinesia had a tendency to reduce. Partial normalization of the bone tissue mineral component occurred during a 20 day recovery period following hypokinesia.

  10. Textile-Based Electronic Components for Energy Applications: Principles, Problems, and Perspective

    PubMed Central

    Kaushik, Vishakha; Lee, Jaehong; Hong, Juree; Lee, Seulah; Lee, Sanggeun; Seo, Jungmok; Mahata, Chandreswar; Lee, Taeyoon

    2015-01-01

    Textile-based electronic components have gained interest in the fields of science and technology. Recent developments in nanotechnology have enabled the integration of electronic components into textiles while retaining desirable characteristics such as flexibility, strength, and conductivity. Various materials were investigated in detail to obtain current conductive textile technology, and the integration of electronic components into these textiles shows great promise for common everyday applications. The harvest and storage of energy in textile electronics is a challenge that requires further attention in order to enable complete adoption of this technology in practical implementations. This review focuses on the various conductive textiles, their methods of preparation, and textile-based electronic components. We also focus on fabrication and the function of textile-based energy harvesting and storage devices, discuss their fundamental limitations, and suggest new areas of study. PMID:28347078

  11. Textile-Based Electronic Components for Energy Applications: Principles, Problems, and Perspective.

    PubMed

    Kaushik, Vishakha; Lee, Jaehong; Hong, Juree; Lee, Seulah; Lee, Sanggeun; Seo, Jungmok; Mahata, Chandreswar; Lee, Taeyoon

    2015-09-07

    Textile-based electronic components have gained interest in the fields of science and technology. Recent developments in nanotechnology have enabled the integration of electronic components into textiles while retaining desirable characteristics such as flexibility, strength, and conductivity. Various materials were investigated in detail to obtain current conductive textile technology, and the integration of electronic components into these textiles shows great promise for common everyday applications. The harvest and storage of energy in textile electronics is a challenge that requires further attention in order to enable complete adoption of this technology in practical implementations. This review focuses on the various conductive textiles, their methods of preparation, and textile-based electronic components. We also focus on fabrication and the function of textile-based energy harvesting and storage devices, discuss their fundamental limitations, and suggest new areas of study.

  12. Airborne mineral components and trace metals in Paris region: spatial and temporal variability.

    PubMed

    Poulakis, E; Theodosi, C; Bressi, M; Sciare, J; Ghersi, V; Mihalopoulos, N

    2015-10-01

    A variety of mineral components (Al, Fe) and trace metals (V, Cr, Mn, Ni, Cu, Zn, Cd, Pb) were simultaneously measured in PM2.5 and PM10 fractions at three different locations (traffic, urban, and suburban) in the Greater Paris Area (GPA) on a daily basis throughout a year. Mineral species and trace metal levels measured in both fractions are in agreement with those reported in the literature and below the thresholds defined by the European guidelines for toxic metals (Cd, Ni, Pb). Size distribution between PM2.5 and PM10 fractions revealed that mineral components prevail in the coarse mode, while trace metals are mainly confined in the fine one. Enrichment factor analysis, statistical analysis, and seasonal variability suggest that elements such as Mn, Cr, Zn, Fe, and Cu are attributed to traffic, V and Ni to oil combustion while Cd and Pb to industrial activities with regional origin. Meteorological parameters such as rain, boundary layer height (BLH), and air mass origin were found to significantly influence element concentrations. Periods with high frequency of northern and eastern air masses (from high populated and industrialized areas) are characterized by high metal concentrations. Finally, inner city and traffic emissions were also evaluated in PM2.5 fraction. Significant contributions (>50 %) were measured in the traffic site for Mn, Fe, Cr, Zn, and Cu, confirming that vehicle emissions contribute significantly to their levels, while in the urban site, the lower contributions (18 to 33 %) for all measured metals highlight the influence of regional sources on their levels.

  13. Screen printed passive components for flexible power electronics

    NASA Astrophysics Data System (ADS)

    Ostfeld, Aminy E.; Deckman, Igal; Gaikwad, Abhinav M.; Lochner, Claire M.; Arias, Ana C.

    2015-10-01

    Additive and low-temperature printing processes enable the integration of diverse electronic devices, both power-supplying and power-consuming, on flexible substrates at low cost. Production of a complete electronic system from these devices, however, often requires power electronics to convert between the various operating voltages of the devices. Passive components—inductors, capacitors, and resistors—perform functions such as filtering, short-term energy storage, and voltage measurement, which are vital in power electronics and many other applications. In this paper, we present screen-printed inductors, capacitors, resistors and an RLC circuit on flexible plastic substrates, and report on the design process for minimization of inductor series resistance that enables their use in power electronics. Printed inductors and resistors are then incorporated into a step-up voltage regulator circuit. Organic light-emitting diodes and a flexible lithium ion battery are fabricated and the voltage regulator is used to power the diodes from the battery, demonstrating the potential of printed passive components to replace conventional surface-mount components in a DC-DC converter application.

  14. Screen printed passive components for flexible power electronics

    PubMed Central

    Ostfeld, Aminy E.; Deckman, Igal; Gaikwad, Abhinav M.; Lochner, Claire M.; Arias, Ana C.

    2015-01-01

    Additive and low-temperature printing processes enable the integration of diverse electronic devices, both power-supplying and power-consuming, on flexible substrates at low cost. Production of a complete electronic system from these devices, however, often requires power electronics to convert between the various operating voltages of the devices. Passive components—inductors, capacitors, and resistors—perform functions such as filtering, short-term energy storage, and voltage measurement, which are vital in power electronics and many other applications. In this paper, we present screen-printed inductors, capacitors, resistors and an RLC circuit on flexible plastic substrates, and report on the design process for minimization of inductor series resistance that enables their use in power electronics. Printed inductors and resistors are then incorporated into a step-up voltage regulator circuit. Organic light-emitting diodes and a flexible lithium ion battery are fabricated and the voltage regulator is used to power the diodes from the battery, demonstrating the potential of printed passive components to replace conventional surface-mount components in a DC-DC converter application. PMID:26514331

  15. Basic studies on the role of components of Bacillus megaterium as flotation biocollectors in sulphide mineral separation.

    PubMed

    Vasanthakumar, Balasubramanian; Ravishankar, Honnavar; Subramanian, Sankaran

    2014-03-01

    Studies were carried out to assess the utility of the cellular and extracellular constituents of Bacillus megaterium for the flotation of sphalerite and galena minerals. Based on the flotation results on the individual minerals, it was observed that sphalerite was preferentially floated compared to galena. A maximum selectivity index (SI) value of 11.7 was achieved in the presence of the soluble fraction of the thermolysed cells, which was higher than that obtained with the intact cells (SI of 6.5) and the insoluble fraction of the thermolysed cells (SI of 9.6). The results of the various enzymatic treatment tests revealed that extracellular DNA played a vital role in the selective flotation of sphalerite. A noteworthy finding was that the single-stranded DNA (ssDNA) had a higher biocollector capacity vis-à-vis the double-stranded DNA (dsDNA), leading to better flotation efficiency. About 95 % recovery of sphalerite could be achieved from the mineral mixture by the combined addition of the ssDNA with the non-DNA components of the bacterial cells, resulting in a maximum SI of 19.1. Calcium and phosphate components of the nutrient media were found to be essential for better selectivity of separation of sphalerite. The mechanisms of microbe-mineral interaction are discussed.

  16. Electronic Components and Systems for Cryogenic Space Applications

    NASA Technical Reports Server (NTRS)

    Patterson, R. L.; Hammoud, A.; Dickman, J. E.; Gerber, S.; Elbuluk, M. E.; Overton, E.

    2001-01-01

    Electronic components and systems capable of operation at cryogenic temperatures are anticipated in many future NASA space missions such as deep space probes and planetary surface exploration. For example, an unheated interplanetary probe launched to explore the rings of Saturn would reach an average temperature near Saturn of about - 183 C. In addition to surviving the deep space harsh environment, electronics capable of low temperature operation would contribute to improving circuit performance, increasing system efficiency, and reducing payload development and launch costs. Terrestrial applications where components and systems must operate in low temperature environments include cryogenic instrumentation, superconducting magnetic energy storage, magnetic levitation transportation system, and arctic exploration. An on-going research and development program at the NASA Glenn Research Center focuses on the development of reliable electronic devices and efficient power systems capable of surviving in low temperature environments. An overview of the program will be presented in this paper. A description of the low temperature test facilities along with selected data obtained from in-house component testing will also be discussed. Ongoing research activities that are being performed in collaboration with various organizations will also be presented.

  17. Component Repair Experiment-1: An Experiment Evaluating Electronic Component-Level Repair During Spaceflight

    NASA Technical Reports Server (NTRS)

    Easton, John W.; Struk, Peter M.

    2012-01-01

    The Component Repair Experiment-1 (CRE-1) examines the capability for astronauts to perform electronics repair tasks in space. The goal is to determine the current capabilities and limits for the crew, and to make recommendations to improve and expand the range of work that astronauts may perform. CRE-1 provided two-layer, functional circuit boards and replacement components, a small tool kit, written and video training materials, and 1 hr of hands on training for the crew slated to perform the experiment approximately 7 months prior to the mission. Astronauts Michael Fincke and Sandra Magnus performed the work aboard the International Space Station (ISS) in February and March 2009. The astronauts were able to remove and replace components successfully, demonstrating the feasibility of performing component-level electronics repairs within a spacecraft. Several unsuccessful tasks demonstrated areas in need of improvement. These include improved and longer training prior to a mission, an improved soldering iron with a higher operating temperature and steady power source, video training and practice boards for refresher work or practice before a repair, and improved and varied hand tools and containment system.

  18. 77 FR 51572 - Certain Wireless Consumer Electronics Devices and Components Thereof; Institution of...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2012-08-24

    ... Electronics Devices and Components Thereof; Institution of Investigation Pursuant to 19 U.S.C. 1337 AGENCY: U... importation of certain wireless consumer electronics devices and components thereof by reason of infringement... wireless consumer electronics devices and components thereof that infringe one or more of claims 1, 6, 7, 9...

  19. Advanced Power Electronics Components

    NASA Technical Reports Server (NTRS)

    Schwarze, Gene E.

    2004-01-01

    This paper will give a description and status of the Advanced Power Electronics Materials and Components Technology program being conducted by the NASA Glenn Research Center for future aerospace power applications. The focus of this research program is on the following: 1) New and/or significantly improved dielectric materials for the development of power capacitors with increased volumetric efficiency, energy density, and operating temperature. Materials being investigated include nanocrystalline and composite ceramic dielectrics and diamond-like carbon films; 2) New and/or significantly improved high frequency, high temperature, low loss soft magnetic materials for the development of transformers/inductors with increased power/energy density, electrical efficiency, and operating temperature. Materials being investigated include nanocrystalline and nanocomposite soft magnetic materials; 3) Packaged high temperature, high power density, high voltage, and low loss SiC diodes and switches. Development of high quality 4H- and 6H- SiC atomically smooth substrates to significantly improve device performance is a major emphasis of the SiC materials program; 4) Demonstration of high temperature (> 200 C) circuits using the components developed above.

  20. Conflict Minerals in Electronic Systems: An Overview and Critique of Legal Initiatives.

    PubMed

    Jameson, N Jordan; Song, Xin; Pecht, Michael

    2016-10-01

    The Democratic Republic of Congo has vast natural resources, many of which are regularly exploited by the electronics industry. Unfortunately, in addition to these resources, there are widespread human rights abuses committed by armed groups entrenched in the eastern part of the Democratic Republic of Congo. These armed groups are using profits from these minerals as a source of funding. Their human rights abuses have led to a growing humanitarian interest in the region and prompted the international community to action. This paper explores the conflicts in the Democratic Republic of Congo, provides an understanding of the link between human rights abuses and conflict minerals, and interprets and critiques the legal actions of the international community.

  1. Effect of electrolyte on surface free energy components of feldspar minerals using thin-layer wicking method.

    PubMed

    Karagüzel, C; Can, M F; Sönmez, E; Celik, M S

    2005-05-01

    Application of the thin-layer wicking (TLW) technique on powdered minerals is useful for characterizing their surfaces. Albite (Na-feldspar) and orthoclase (K-feldspar) are feldspar minerals which are frequently found in the same matrix. Despite similarities in their physicochemical properties, separation of these minerals from each other by flotation is generally possible in the presence of monovalent salts such as NaCl. Both albite and orthoclase exhibit the same microflotation properties and rather close electrokinetic profiles in the absence of salt. In this study, contact angles of albite and orthoclase determined by the TLW technique yielded close values in the absence and presence of amine collector. While the calculated surface energies and their components determined using contact angle data reveal that the energy terms remain farther apart in the absence of the collector, the differences narrow down at collector concentrations where full flotation recoveries are obtained. However, the effect of addition of NaCl on contact angles and surface free energy components at constant amine concentration indicates that albite is significantly affected by salt addition, whereas orthoclase remains marginally affected. This interesting finding is explained on the basis of ion-exchange properties, the stability of the interface, flotation data, and zeta potential data in the presence of NaCl.

  2. Evaluation of runaway-electron effects on plasma-facing components for NET

    NASA Astrophysics Data System (ADS)

    Bolt, H.; Calén, H.

    1991-03-01

    Runaway electrons which are generated during disruptions can cause serious damage to plasma facing components in a next generation device like NET. A study was performed to quantify the response of NET plasma facing components to runaway-electron impact. For the determination of the energy deposition in the component materials Monte Carlo computations were performed. Since the subsurface metal structures can be strongly heated under runaway-electron impact from the computed results damage threshold values for the thermal excursions were derived. These damage thresholds are strongly dependent on the materials selection and the component design. For a carbonmolybdenum divertor with 10 and 20 mm carbon armour thickness and 1 degree electron incidence the damage thresholds are 100 MJ/m 2 and 220 MJ/m 2. The thresholds for a carbon-copper divertor under the same conditions are about 50% lower. On the first wall damage is anticipated for energy depositions above 180 MJ/m 2.

  3. QEMSCAN° (Quantitative Evaluation of Minerals by Scanning Electron Microscopy): capability and application to fracture characterization in geothermal systems

    NASA Astrophysics Data System (ADS)

    Ayling, B.; Rose, P. E.; Zemach, E.; Drakos, P. S.; Petty, S.

    2011-12-01

    Fractures are important conduits for fluids in geothermal systems, and the creation and maintenance of fracture permeability is a fundamental aspect of EGS (Engineered Geothermal System) development. Hydraulic or chemical stimulation techniques are often employed to achieve this. In the case of chemical stimulation, an understanding of the minerals present in the fractures themselves is desirable to better design a stimulation effort (i.e. which chemical to use and how much). Borehole televiewer surveys provide important information about regional and local stress regimes and fracture characteristics (e.g. fracture aperture), and XRD is useful for examining bulk rock mineralogy, but neither technique is able to quantify the distribution of these minerals in fractures. QEMSCAN° is a fully-automated micro-analysis system that enables quantitative chemical analysis of materials and generation of high-resolution mineral maps and images as well as porosity structure. It uses a scanning electron microscopy platform (SEM) with an electron beam source in combination with four energy-dispersive X-ray spectrometers (EDS). The measured backscattered electron and electron-induced secondary X-ray emission spectra are used to classify sample mineralogy. Initial applications of QEMSCAN° technology were predominantly in the minerals industry and application to geothermal problems has remained limited to date. In this pilot study, the potential application of QEMSCAN° technology to fracture characterization was evaluated using samples of representative mineralized fractures in two geothermal systems (Newberry Volcano, Oregon and Brady's geothermal field, Nevada). QEMSCAN° results were compared with XRD and petrographic techniques. Nine samples were analyzed from each field, collected from the drill core in the 1000-1500 m depth range in two shallow wells (GEO-N2 at Newberry Volcano and BCH-3 at Brady's). The samples were prepared as polished thin sections for QEMSCAN° analysis

  4. Antenna with distributed strip and integrated electronic components

    DOEpatents

    Rodenbeck, Christopher T [Albuquerque, NM; Payne, Jason A [Albuquerque, NM; Ottesen, Cory W [Albuquerque, NM

    2008-08-05

    An antenna comprises electrical conductors arranged to form a radiating element including a folded line configuration and a distributed strip configuration, where the radiating element can be in proximity to a ground conductor and/or arranged as a dipole. Embodiments of the antenna include conductor patterns formed on a printed wiring board, having a ground plane, spacedly adjacent to and coplanar with the radiating element. An antenna can comprise a distributed strip patterned on a printed wiring board, integrated with electronic components mounted on top of or below the distributed strip, and substantially within the extents of the distributed strip. Mounting of electronic components on top of or below the distributed strip has little effect on the performance of the antenna, and allows for realizing the combination of the antenna and integrated components in a compact form. An embodiment of the invention comprises an antenna including a distributed strip, integrated with a battery mounted on the distributed strip.

  5. Arbitrary amplitude fast electron-acoustic solitons in three-electron component space plasmas

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Mbuli, L. N.; Maharaj, S. K.; Department of Physics, University of the Western Cape

    We examine the characteristics of fast electron-acoustic solitons in a four-component unmagnetised plasma model consisting of cool, warm, and hot electrons, and cool ions. We retain the inertia and pressure for all the plasma species by assuming adiabatic fluid behaviour for all the species. By using the Sagdeev pseudo-potential technique, the allowable Mach number ranges for fast electron-acoustic solitary waves are explored and discussed. It is found that the cool and warm electron number densities determine the polarity switch of the fast electron-acoustic solitons which are limited by either the occurrence of fast electron-acoustic double layers or warm and hotmore » electron number density becoming unreal. For the first time in the study of solitons, we report on the coexistence of fast electron-acoustic solitons, in addition to the regular fast electron-acoustic solitons and double layers in our multi-species plasma model. Our results are applied to the generation of broadband electrostatic noise in the dayside auroral region.« less

  6. Calculating Strain Relief in Electronic-Component Leads

    NASA Technical Reports Server (NTRS)

    Snytsheuvel, H.

    1985-01-01

    Stress/strain formulas applicable to design of electronic-component leads compiled in report. Such things as factors of safety and whether or not lead is likely to fall in service determined in advance. Set of formulas is simple enough to be solved on programable hand-held calculator.

  7. Crystallinity of chitin and carbonate mineral components independently record crustacean biomineralization

    NASA Astrophysics Data System (ADS)

    Mergelsberg, S. T.; Michel, F. M.; Mukhopadhyay, B.; Dove, P. M.

    2016-02-01

    Some of the earliest evidence for crustacean organisms is attributed to the discovery of Peytoia nathorsti, a predatory arthropod from 500 Ma (Cong, P. et al., 2014). These animals presumably began with a soft exoskeleton and evolved to fill diverse ecological niches while adopting a mineralized skeleton that is rarely preserved in its entirety (Klompmaker, A.A. et al., 2015). That is, one or more of the primary skeleton components (calcium carbonate minerals, the polysaccharide chitin, and minor proteins) were subject to decomposition during fossilization and preservation. These missing pieces present a significant obstacle to reconstructing ecosystem variability over long time periods. Our recent study of the exoskeletons from ten Malacostraca species suggests the physical and chemical structure of chitin holds promise as a secondary proxy for reconstructing skeleton reinforcement. Using high-energy X-ray diffraction and a novel Raman spectroscopy technique to enhance resolution, we determined the detailed nanostructures of chitin and the associated calcium carbonate minerals that comprise the cuticles of multiple body parts. Crab cuticles from the order Brachyura (Dungeness and Rock crabs) exhibit elevated crystallinities of the chitin and calcite in the more reinforced structures (such as the claw). In contrast, the cuticle of lobster body parts show a much greater variability of calcium carbonate crystallinity and a very consistent crystallinity of chitin. Calcite and chitin crystallinity exhibit a dependency within a species (body part to body part), but these dependencies can be different between taxa. Insights from this study suggest high resolution structural analyses hold promise for developing new proxies for the paleo-environment and paleo-ecology of specific Malacostraca animals, regardless of how well the specimen is preserved.

  8. Electrical and electronic devices and components: A compilation

    NASA Technical Reports Server (NTRS)

    1975-01-01

    Components and techniques which may be useful in the electronics industry are described. Topics discussed include transducer technology, printed-circuit technology, solid state devices, MOS transistors, Gunn device, microwave antennas, and position indicators.

  9. Radiation studies of optical and electronic components used in astronomical satellite studies

    NASA Technical Reports Server (NTRS)

    Becher, J.; Kernell, R. L.

    1981-01-01

    The synchronous orbit of the IUE carries the satellite through Earth's outer electron belt. A 40 mCi Sr90 source was used to simulate these electrons. A 5 mCi source of Co60 was used to simulate bremmstrahlung. A 10 MeV electron Linac and a 1.7 MeV electron Van de Graaf wer used to investigate the energy dependence of radiation effects and to perform radiations at a high flux rate. A 100 MeV proton cyclotron was used to simulate cosmic rays. Results are presented for three instrument systems of the IUE and measurements for specific components are reported. The three instrument systems were the ultraviolet converter, the fine error sensor (FES), and the SEC vidicon camera tube. The components were optical glasses, electronic components, silicon photodiodes, and UV window materials.

  10. Pamela observational capabilities of Jovian electrons component

    NASA Astrophysics Data System (ADS)

    di Felice, V.; PAMELA Collaboration

    PAMELA is a satellite-borne experiment that will be launched in the first half of 2006 It will make long duration measurements of cosmic radiation over an extended energy range 80Mev to 200 GeV Specifically PAMELA will measure the cosmic-ray antiproton and positron spectra over the largest energy range ever achieved 80MeV -- 190 GeV and will search for antinuclei with unprecedented sensitivity Furthermore it will measure the light nuclear component of cosmic rays and investigate phenomena connected with solar and earth physics The apparatus consists of a time of flight system a magnetic spectrometer an electromagnetic imaging calorimeter a shower tail catcher scintillator a neutron detector and an anticoincidence system In this work a study of the PAMELA capabilities to detect Jovian electrons is presented The Jovian magnetosphere is a powerful accelerator of electrons to several tens of MeV as observed at first by Pioneer 10 spacecraft 1973 The propagation of Jovian electrons to Earth is affected by modulation due to Corotating Interaction Regions CIR Their flux at Earth is moreover modulated because every sim 13 months Earth and Jupiter are aligned along the average direction of the Parker spiral of the Interplanetary Magnetic Field PAMELA will be able to measure the high energy tail of the Jovian electrons in the energy range from 50 MeV up to 130 MeV Moreover it will be possible to extract the Jovian component reaccelated at the solar wind termination shock above 130 MeV up to 2 GeV from the galactic flux

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

    NASA Astrophysics Data System (ADS)

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

    1996-04-01

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

  12. Clay Minerals

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    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 studiesmore » 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.« less

  13. Electric vehicle recycling 2020: Key component power electronics.

    PubMed

    Bulach, Winfried; Schüler, Doris; Sellin, Guido; Elwert, Tobias; Schmid, Dieter; Goldmann, Daniel; Buchert, Matthias; Kammer, Ulrich

    2018-04-01

    Electromobility will play a key role in order to reach the specified ambitious greenhouse gas reduction targets in the German transport sector of 42% between 1990 and 2030. Subsequently, a significant rise in the sale of electric vehicles (EVs) is to be anticipated in future. The amount of EVs to be recycled will rise correspondingly after a delay. This includes the recyclable power electronics modules which are incorporated in every EV as an important component for energy management. Current recycling methods using car shredders and subsequent post shredder technologies show high recycling rates for the bulk metals but are still associated with high losses of precious and strategic metals such as gold, silver, platinum, palladium and tantalum. For this reason, the project 'Electric vehicle recycling 2020 - key component power electronics' developed an optimised recycling route for recycling power electronics modules from EVs which is also practicable in series production and can be implemented using standardised technology. This 'WEEE recycling route' involves the disassembly of the power electronics from the vehicle and a subsequent recycling in an electronic end-of-life equipment recycling plant. The developed recycling process is economical under the current conditions and raw material prices, even though it involves considerably higher costs than recycling using the car shredder. The life cycle assessment shows basically good results, both for the traditional car shredder route and the developed WEEE recycling route: the latter provides additional benefits from some higher recovery rates and corresponding credits.

  14. Detection of counterfeit electronic components through ambient mass spectrometry and chemometrics.

    PubMed

    Pfeuffer, Kevin P; Caldwell, Jack; Shelley, Jake T; Ray, Steven J; Hieftje, Gary M

    2014-09-21

    In the last several years, illicit electronic components have been discovered in the inventories of several distributors and even installed in commercial and military products. Illicit or counterfeit electronic components include a broad category of devices that can range from the correct unit with a more recent date code to lower-specification or non-working systems with altered names, manufacturers and date codes. Current methodologies for identification of counterfeit electronics rely on visual microscopy by expert users and, while effective, are very time-consuming. Here, a plasma-based ambient desorption/ionization source, the flowing atmospheric pressure afterglow (FAPA) is used to generate a mass-spectral fingerprint from the surface of a variety of discrete electronic integrated circuits (ICs). Chemometric methods, specifically principal component analysis (PCA) and the bootstrapped error-adjusted single-sample technique (BEAST), are used successfully to differentiate between genuine and counterfeit ICs. In addition, chemical and physical surface-removal techniques are explored and suggest which surface-altering techniques were utilized by counterfeiters.

  15. Electronic Components and Circuits for Extreme Temperature Environments

    NASA Technical Reports Server (NTRS)

    Patterson, Richard L.; Hammoud, Ahmad; Dickman, John E.; Gerber, Scott

    2003-01-01

    Planetary exploration missions and deep space probes require electrical power management and control systems that are capable of efficient and reliable operation in very low temperature environments. Presently, spacecraft operating in the cold environment of deep space carry a large number of radioisotope heating units in order to maintain the surrounding temperature of the on-board electronics at approximately 20 C. Electronics capable of operation at cryogenic temperatures will not only tolerate the hostile environment of deep space but also reduce system size and weight by eliminating or reducing the radioisotope heating units and their associate structures; thereby reducing system development as well as launch costs. In addition, power electronic circuits designed for operation at low temperatures are expected to result in more efficient systems than those at room temperature. This improvement results from better behavior and tolerance in the electrical and thermal properties of semiconductor and dielectric materials at low temperatures. The Low Temperature Electronics Program at the NASA Glenn Research Center focuses on research and development of electrical components, circuits, and systems suitable for applications in the aerospace environment and deep space exploration missions. Research is being conducted on devices and systems for reliable use down to cryogenic temperatures. Some of the commercial-off-the-shelf as well as developed components that are being characterized include switching devices, resistors, magnetics, and capacitors. Semiconductor devices and integrated circuits including digital-to-analog and analog-to-digital converters, DC/DC converters, operational amplifiers, and oscillators are also being investigated for potential use in low temperature applications. An overview of the NASA Glenn Research Center Low Temperature Electronic Program will be presented in this paper. A description of the low temperature test facilities along with

  16. Incineration, pyrolysis and gasification of electronic waste

    NASA Astrophysics Data System (ADS)

    Gurgul, Agnieszka; Szczepaniak, Włodzimierz; Zabłocka-Malicka, Monika

    2017-11-01

    Three high temperature processes of the electronic waste processing: smelting/incineration, pyrolysis and gasification were shortly discussed. The most distinctive feature of electronic waste is complexity of components and their integration. This type of waste consists of polymeric materials and has high content of valuable metals that could be recovered. The purpose of thermal treatment of electronic waste is elimination of plastic components (especially epoxy resins) while leaving non-volatile mineral and metallic phases in more or less original forms. Additionally, the gaseous product of the process after cleaning may be used for energy recovery or as syngas.

  17. A review of typical thermal fatigue failure models for solder joints of electronic components

    NASA Astrophysics Data System (ADS)

    Li, Xiaoyan; Sun, Ruifeng; Wang, Yongdong

    2017-09-01

    For electronic components, cyclic plastic strain makes it easier to accumulate fatigue damage than elastic strain. When the solder joints undertake thermal expansion or cold contraction, different thermal strain of the electronic component and its corresponding substrate is caused by the different coefficient of thermal expansion of the electronic component and its corresponding substrate, leading to the phenomenon of stress concentration. So repeatedly, cracks began to sprout and gradually extend [1]. In this paper, the typical thermal fatigue failure models of solder joints of electronic components are classified and the methods of obtaining the parameters in the model are summarized based on domestic and foreign literature research.

  18. Fixture aids soldering of electronic components on circuit board

    NASA Technical Reports Server (NTRS)

    Ross, M. H.

    1966-01-01

    Spring clamp fixture holds small electronic components in a desired position while they are being soldered on a circuit board. The spring clamp is clipped on the edge of the circuit board and an adjustable spring-steel boom holds components against the board. The felt pad at the end of the boom is replaced with different attachments for other holding tasks.

  19. Thermoelectric-enhanced, liquid-based cooling of a multi-component electronic system

    DOEpatents

    Chainer, Timothy J; Graybill, David P; Iyengar, Madhusudan K; Kamath, Vinod; Kochuparambil, Bejoy J; Schmidt, Roger R; Steinke, Mark E

    2015-11-10

    Methods are provided for facilitating cooling of an electronic component. The methods include providing: a liquid-cooled structure, a thermal conduction path coupling the electronic component and the liquid-cooled structure, a coolant loop in fluid communication with a coolant-carrying channel of the liquid-cooled structure, and an outdoor-air-cooled heat exchange unit coupled to facilitate heat transfer from the liquid-cooled structure via, at least in part, the coolant loop. The thermoelectric array facilitates transfer of heat from the electronic component to the liquid-cooled structure, and the heat exchange unit cools coolant passing through the coolant loop by dissipating heat from the coolant to outdoor ambient air. In one implementation, temperature of coolant entering the liquid-cooled structure is greater than temperature of the outdoor ambient air to which heat is dissipated.

  20. Thermoelectric-enhanced, liquid-based cooling of a multi-component electronic system

    DOEpatents

    Chainer, Timothy J; Graybill, David P; Iyengar, Madhusudan K; Kamath, Vinod; Kochuparambil, Bejoy J; Schmidt, Roger R; Steinke, Mark E

    2015-05-12

    Apparatus and method are provided for facilitating cooling of an electronic component. The apparatus includes a liquid-cooled structure, a thermal conduction path coupling the electronic component and the liquid-cooled structure, a coolant loop in fluid communication with a coolant-carrying channel of the liquid-cooled structure, and an outdoor-air-cooled heat exchange unit coupled to facilitate heat transfer from the liquid-cooled structure via, at least in part, the coolant loop. The thermoelectric array facilitates transfer of heat from the electronic component to the liquid-cooled structure, and the heat exchange unit cools coolant passing through the coolant loop by dissipating heat from the coolant to outdoor ambient air. In one implementation, temperature of coolant entering the liquid-cooled structure is greater than temperature of the outdoor ambient air to which heat is dissipated.

  1. 77 FR 32996 - Certain Handheld Electronic Computing Devices, Related Software, and Components Thereof...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2012-06-04

    ... INTERNATIONAL TRADE COMMISSION [Investigation No. 337-TA-769] Certain Handheld Electronic Computing Devices, Related Software, and Components Thereof; Termination of the Investigation Based on... electronic computing devices, related software, and components thereof by reason of infringement of certain...

  2. Observation of nitrate coatings on atmospheric mineral dust particles

    NASA Astrophysics Data System (ADS)

    Li, W. J.; Shao, L. Y.

    2009-03-01

    Nitrate compounds have received much attention because of their ability to alter the hygroscopic properties and cloud condensation nuclei (CCN) activity of mineral dust particles in the atmosphere. However, very little is known about specific characteristics of ambient nitrate-coated mineral particles on an individual particle scale. In this study, sample collection was conducted during brown haze and dust episodes between 24 May and 21 June 2007 in Beijing, northern China. Sizes, morphologies, and compositions of 332 mineral dust particles together with their coatings were analyzed using transmission electron microscopy (TEM) coupled with energy-dispersive X-ray (EDX) microanalyses. Structures of some mineral particles were verified using selected-area electron diffraction (SAED). TEM observation indicates that approximately 90% of the collected mineral particles are covered by visible coatings in haze samples whereas only 5% are coated in the dust sample. 92% of the analyzed mineral particles are covered with Ca-, Mg-, and Na-rich coatings, and 8% are associated with K- and S-rich coatings. The majority of coatings contain Ca, Mg, O, and N with minor amounts of S and Cl, suggesting that they are possibly nitrates mixed with small amounts of sulfates and chlorides. These nitrate coatings are strongly correlated with the presence of alkaline mineral components (e.g., calcite and dolomite). CaSO4 particles with diameters from 10 to 500 nm were also detected in the coatings including Ca(NO3)2 and Mg(NO3)2. Our results indicate that mineral particles in brown haze episodes were involved in atmospheric heterogeneous reactions with two or more acidic gases (e.g., SO2, NO2, HCl, and HNO3). Mineral particles that acquire hygroscopic nitrate coatings tend to be more spherical and larger, enhancing their light scattering and CCN activity, both of which have cooling effects on the climate.

  3. Simulation of multi-element multispectral UV radiation source for optical-electronic system of minerals luminescence analysis

    NASA Astrophysics Data System (ADS)

    Peretyagin, Vladimir S.; Korolev, Timofey K.; Chertov, Aleksandr N.

    2017-02-01

    The problems of dressability the solid minerals are attracted attention of specialists, where the extraction of mineral raw materials is a significant sector of the economy. There are a significant amount of mineral ore dressability methods. At the moment the radiometric dressability methods are considered the most promising. One of radiometric methods is method photoluminescence. This method is based on the spectral analysis, amplitude and kinetic parameters luminescence of minerals (under UV radiation), as well as color parameters of radiation. The absence of developed scientific and methodological approaches of analysis irradiation area to UV radiation as well as absence the relevant radiation sources are the factors which hinder development and use of photoluminescence method. The present work is devoted to the development of multi-element UV radiation source designed for the solution problem of analysis and sorting minerals by their selective luminescence. This article is presented a method of theoretical modeling of the radiation devices based on UV LEDs. The models consider such factors as spectral component, the spatial and energy parameters of the LEDs. Also, this article is presented the results of experimental studies of the some samples minerals.

  4. [Analysis of the mineral elements of Lactuca sativa under the condition of different spectral components].

    PubMed

    Chen, Xiao-Li; Guo, Wen-Zhong; Xue, Xu-Zhang; Wang, Li-Chun; Li, Liang; Chen, Fei

    2013-08-01

    Mineral elements absorption and content of Lactuca sativa under different spectral component conditions were studied by ICP-AES technology. The results showed that: (1) For Lactuca sativa, the average proportion for Ca : Mg : K : Na : P was 5.5 : 2.5 : 2.3 : 1.5 : 1.0, the average proportion for Fe : Mn : Zn : Cu : B was 25.9 : 5.9 : 2.8 : 1.1 : 1.0; (2) The absorptions for K, P, Ca, Mg and B are the largest under the LED treatment R/B = 1 : 2.75, red light from fluorescent lamps and LED can both promote the absorptions of Fe and Cu; (3)The LED treatments exhibiting relatively higher content of mineral elements are R/B = 1 : 2.75 and R/W = 1 : 1 while higher dry matter accumulations are R/B = 1 : 2.75 and B/W = 1 : 1.

  5. Virtual enterprise model for the electronic components business in the Nuclear Weapons Complex

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Ferguson, T.J.; Long, K.S.; Sayre, J.A.

    1994-08-01

    The electronic components business within the Nuclear Weapons Complex spans organizational and Department of Energy contractor boundaries. An assessment of the current processes indicates a need for fundamentally changing the way electronic components are developed, procured, and manufactured. A model is provided based on a virtual enterprise that recognizes distinctive competencies within the Nuclear Weapons Complex and at the vendors. The model incorporates changes that reduce component delivery cycle time and improve cost effectiveness while delivering components of the appropriate quality.

  6. Structural relations between collagen and mineral in bone as determined by high voltage electron microscopic tomography

    NASA Technical Reports Server (NTRS)

    Landis, W. J.; Hodgens, K. J.; Arena, J.; Song, M. J.; McEwen, B. F.

    1996-01-01

    Aspects of the ultrastructural interaction between collagen and mineral crystals in embryonic chick bone have been examined by the novel technique of high voltage electron microscopic tomography to obtain three-dimensional information concerning extracellular calcification in this tissue. Newly mineralizing osteoid along periosteal surfaces of mid-diaphyseal regions from normal chick tibiae was embedded, cut into 0.25 microns thick sections, and documented at 1.0 MV in the Albany AEI-EM7 high voltage electron microscope. The areas of the tissue studied contained electron dense mineral crystals associated with collagen fibrils, some marked by crystals disposed along their cylindrically shaped lengths. Tomographic reconstructions of one site with two mineralizing fibrils were computed from a 5 degrees tilt series of micrographs over a +/- 60 degrees range. Reconstructions showed that the mineral crystals were platelets of irregular shape. Their sizes were variable, measured here up to 80 x 30 x 8 nm in length, width, and thickness, respectively. The longest crystal dimension, corresponding to the c-axis crystallographically, was generally parallel to the collagen fibril long axis. Individual crystals were oriented parallel to one another in each fibril examined. They were also parallel in the neighboring but apparently spatially separate fibrils. Crystals were periodically (approximately 67 nm repeat distance) arranged along the fibrils and their location appeared to correspond to collagen hole and overlap zones defined by geometrical imaging techniques. The crystals appeared to be continuously distributed along a fibril, their size and number increasing in a tapered fashion from a relatively narrow tip containing smaller and infrequent crystals to wider regions having more densely packed and larger crystals. Defined for the first time by direct visual 3D imaging, these data describe the size, shape, location, orientation, and development of early crystals in normal

  7. [Determination and principal component analysis of mineral elements based on ICP-OES in Nitraria roborowskii fruits from different regions].

    PubMed

    Yuan, Yuan-Yuan; Zhou, Yu-Bi; Sun, Jing; Deng, Juan; Bai, Ying; Wang, Jie; Lu, Xue-Feng

    2017-06-01

    The content of elements in fifteen different regions of Nitraria roborowskii samples were determined by inductively coupled plasma-atomic emission spectrometry(ICP-OES), and its elemental characteristics were analyzed by principal component analysis. The results indicated that 18 mineral elements were detected in N. roborowskii of which V cannot be detected. In addition, contents of Na, K and Ca showed high concentration. Ti showed maximum content variance, while K is minimum. Four principal components were gained from the original data. The cumulative variance contribution rate is 81.542% and the variance contribution of the first principal component was 44.997%, indicating that Cr, Fe, P and Ca were the characteristic elements of N. roborowskii.Thus, the established method was simple, precise and can be used for determination of mineral elements in N.roborowskii Kom. fruits. The elemental distribution characteristics among N.roborowskii fruits are related to geographical origins which were clearly revealed by PCA. All the results will provide good basis for comprehensive utilization of N.roborowskii. Copyright© by the Chinese Pharmaceutical Association.

  8. 21 CFR 11.200 - Electronic signature components and controls.

    Code of Federal Regulations, 2011 CFR

    2011-04-01

    ... signature components and controls. (a) Electronic signatures that are not based upon biometrics shall: (1... signatures based upon biometrics shall be designed to ensure that they cannot be used by anyone other than...

  9. 21 CFR 11.200 - Electronic signature components and controls.

    Code of Federal Regulations, 2013 CFR

    2013-04-01

    ... signature components and controls. (a) Electronic signatures that are not based upon biometrics shall: (1... signatures based upon biometrics shall be designed to ensure that they cannot be used by anyone other than...

  10. 21 CFR 11.200 - Electronic signature components and controls.

    Code of Federal Regulations, 2012 CFR

    2012-04-01

    ... signature components and controls. (a) Electronic signatures that are not based upon biometrics shall: (1... signatures based upon biometrics shall be designed to ensure that they cannot be used by anyone other than...

  11. 21 CFR 11.200 - Electronic signature components and controls.

    Code of Federal Regulations, 2014 CFR

    2014-04-01

    ... signature components and controls. (a) Electronic signatures that are not based upon biometrics shall: (1... signatures based upon biometrics shall be designed to ensure that they cannot be used by anyone other than...

  12. 78 FR 56245 - Certain Wireless Consumer Electronics Devices and Components Thereof; Notice of Request for...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2013-09-12

    ... Electronics Devices and Components Thereof; Notice of Request for Statements on the Public Interest AGENCY: U... wireless consumer electronics devices and components thereof imported by respondents Acer, Inc. of Taipei... Communications, Inc. of San Diego, California; LG Electronics, Inc. of Seoul, Korea; LG Electronics U.S.A., Inc...

  13. Structure and chemical characteristics of natural mineral deposit Terbunskaya (Lipetsk region, Russia)

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Motyleva, S., E-mail: motyleva-svetlana@mail.ru; Mertvishcheva, M.; Shchuchka, R.

    New knowledge about the mineralogical features Terbunsky mineral. Investigated 5 fractions isolated from the incision (2-2,5 m). Terbunskaya deposit belongs to minerals Santonian age. Scanning electron microscopy and energy dispersive analysis of fractions isolated studied in detail. In the coarse fractions found ancient organic remains of algae and micro-organisms that have been sedimented together with the mineral component during geological periods. The share of organic inclusions does not exceed 1.5%. Chemical composition confirms the presence of silicon and carbonate organisms. Advantageously proportion of minerals having a layered structure with a plurality of micro and nano pore size 600 - 80-nm andmore » an average chemical composition (wt%): Na (0,64), Mg (0,54), Al (13.48), Si (27 57), K (2.39) Ca (0.75)« less

  14. Mineral transformations during the dissolution of uranium ore minerals by dissimilatory metal-reducing bacteria

    NASA Astrophysics Data System (ADS)

    Glasauer, S.; Weidler, P.; Fakra, S.; Tyliszczak, T.; Shuh, D.

    2011-12-01

    Carnotite minerals [X2(UO2)2(VO4)2]; X = K, Ca, Ba, Mn, Na, Cu or Pb] form the major ore of uranium in the Colorado Plateau. These deposits are highly oxidized and contain U(VI) and V(IV). The biotransformation of U(VI) bound in carnotite by bacteria during dissimilatory metal reduction presents a complex puzzle in mineral chemistry. Both U(VI) and V(V) can be respired by metal reducing bacteria, and the mineral structure can change depending on the associated counterion. We incubated anaerobic cultures of S. putrefaciens CN32 with natural carnotite minerals from southeastern Utah in a nutrient-limited defined medium. Strain CN32 is a gram negative bacterium and a terrestrial isolate from New Mexico. The mineral and metal transformations were compared to a system that contained similar concentrations of soluble U(VI) and V(V). Electron (SEM, TEM) microscopies and x-ray spectromicroscopy (STXM) were used in conjunction with XRD to track mineral changes, and bacterial survival was monitored throughout the incubations. Slow rates of metal reduction over 10 months for the treatment with carnotite minerals revealed distinct biotic and abiotic processes, providing insight on mineral transformation and bacteria-metal interactions. The bacteria existed as small flocs or individual cells attached to the mineral phase, but did not adsorb soluble U or V, and accumulated very little of the biominerals. Reduction of mineral V(V) necessarily led to a dismantling of the carnotite structure. Bioreduction of V(V) by CN32 contributed small but profound changes to the mineral system, resulting in new minerals. Abiotic cation exchange within the carnotite group minerals induced the rearrangement of the mineral structures, leading to further mineral transformation. In contrast, bacteria survival was poor for treatments with soluble U(VI) and V(V), although both metals were reduced completely and formed solid UO2 and VO2; we also detected V(III). For these treatments, the bacteria

  15. Three component plasma electron distribution in the intermediate ionized coma of Comet Giacobini-Zinner

    NASA Astrophysics Data System (ADS)

    Zwickl, R. D.; Baker, D. N.; Bame, S. J.; Feldman, W. C.; Fuselier, S. A.; Huebner, W. F.; McComas, D. J.; Young, D. T.

    1986-04-01

    The observation of three distinct components of the electron distribution function measured in the intermediate ionized coma (IIC) and plasma tail of Comet Giacobini-Zinner is reported. It is believed that the cold component represents electrons produced close to the comet nucleus by ionization of cometary matter and subsequent cooling by Coulomb collisions. The second component also appears to be composed of electrons produced by photoionization of cometary neutrals, but sufficiently far from the nucleus that the distributions are largely unaffected by Coulomb interactions. The hot component is probably a population of electrons originating in the solar wind. Throughout the IIC, the electrostatic potential of the spacecraft was very low (less than 0.8 eV), implying that ICE generated very little impact-produced plasma during its passage.

  16. Mineral and organic matrix interaction in normally calcifying tendon visualized in three dimensions by high-voltage electron microscopic tomography and graphic image reconstruction

    NASA Technical Reports Server (NTRS)

    Landis, W. J.; Song, M. J.; Leith, A.; McEwen, L.; McEwen, B. F.

    1993-01-01

    To define the ultrastructural accommodation of mineral crystals by collagen fibrils and other organic matrix components during vertebrate calcification, electron microscopic 3-D reconstructions were generated from the normally mineralizing leg tendons from the domestic turkey, Meleagris gallopavo. Embedded specimens containing initial collagen mineralizing sites were cut into 0.5-micron-thick sections and viewed and photographed at 1.0 MV in the Albany AEI-EM7 high-voltage electron microscope. Tomographic 3-D reconstructions were computed from a 2 degree tilt series of micrographs taken over a minimum angular range of +/- 60 degrees. Reconstructions of longitudinal tendon profiles confirm the presence of irregularly shaped mineral platelets, whose crystallographic c-axes are oriented generally parallel to one another and directed along the collagen long axes. The reconstructions also corroborate observations of a variable crystal length (up to 170 nm measured along crystallographic c-axes), the presence of crystals initially in either the hole or overlap zones of collagen, and crystal growth in the c-axis direction beyond these zones into adjacent overlap and other hole regions. Tomography shows for the first time that crystal width varies (30-45 nm) but crystal thickness is uniform (approximately 4-6 nm at the resolution limit of tomography); more crystals are located in the collagen hole zones than in the overlap regions at the earliest stages of tendon mineralization; the crystallographic c-axes of the platelets lie within +/- 15-20 degrees of one another rather than being perfectly parallel; adjacent platelets are spatially separated by a minimum of 4.2 +/- 1.0 nm; crystals apparently fuse in coplanar alignment to form larger platelets; development of crystals in width occurs to dimensions beyond single collagen hole zones; and a thin envelope of organic origin may be present along or just beneath the surfaces of individual mineral platelets. Implicit in the

  17. System for Cooling of Electronic Components

    NASA Astrophysics Data System (ADS)

    Vasil'ev, L. L.; Grakovich, L. P.; Dragun, L. A.; Zhuravlev, A. S.; Olekhnovich, V. A.; Rabetskii, M. I.

    2017-01-01

    Results of computational and experimental investigations of heat pipes having a predetermined thermal resistance and a system based on these pipes for air cooling of electronic components and diode assemblies of lasers are presented. An efficient compact cooling system comprising heat pipes with an evaporator having a capillary coating of a caked copper powder and a condenser having a developed outer finning, has been deviced. This system makes it possible to remove, to the ambient air, a heat flow of power more than 300 W at a temperature of 40-50°C.

  18. Cooled electronic system with liquid-cooled cold plate and thermal spreader coupled to electronic component

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Chainer, Timothy J.; Graybill, David P.; Iyengar, Madhusudan K.

    Apparatus and method are provided for facilitating cooling of an electronic component. The apparatus includes a liquid-cooled cold plate and a thermal spreader associated with the cold plate. The cold plate includes multiple coolant-carrying channel sections extending within the cold plate, and a thermal conduction surface with a larger surface area than a surface area of the component to be cooled. The thermal spreader includes one or more heat pipes including multiple heat pipe sections. One or more heat pipe sections are partially aligned to a first region of the cold plate, that is, where aligned to the surface tomore » be cooled, and partially aligned to a second region of the cold plate, which is outside the first region. The one or more heat pipes facilitate distribution of heat from the electronic component to coolant-carrying channel sections of the cold plate located in the second region of the cold plate.« less

  19. Cooled electronic system with liquid-cooled cold plate and thermal spreader coupled to electronic component

    DOEpatents

    Chainer, Timothy J.; Graybill, David P.; Iyengar, Madhusudan K.; Kamath, Vinod; Kochuparambil, Bejoy J.; Schmidt, Roger R.; Steinke, Mark E.

    2016-08-09

    Apparatus and method are provided for facilitating cooling of an electronic component. The apparatus includes a liquid-cooled cold plate and a thermal spreader associated with the cold plate. The cold plate includes multiple coolant-carrying channel sections extending within the cold plate, and a thermal conduction surface with a larger surface area than a surface area of the component to be cooled. The thermal spreader includes one or more heat pipes including multiple heat pipe sections. One or more heat pipe sections are partially aligned to a first region of the cold plate, that is, where aligned to the surface to be cooled, and partially aligned to a second region of the cold plate, which is outside the first region. The one or more heat pipes facilitate distribution of heat from the electronic component to coolant-carrying channel sections of the cold plate located in the second region of the cold plate.

  20. Cooled electronic system with liquid-cooled cold plate and thermal spreader coupled to electronic component

    DOEpatents

    Chainer, Timothy J.; Graybill, David P.; Iyengar, Madhusudan K.; Kamath, Vinod; Kochuparambil, Bejoy J.; Schmidt, Roger R.; Steinke, Mark E.

    2016-04-05

    Apparatus and method are provided for facilitating cooling of an electronic component. The apparatus includes a liquid-cooled cold plate and a thermal spreader associated with the cold plate. The cold plate includes multiple coolant-carrying channel sections extending within the cold plate, and a thermal conduction surface with a larger surface area than a surface area of the component to be cooled. The thermal spreader includes one or more heat pipes including multiple heat pipe sections. One or more heat pipe sections are partially aligned to a first region of the cold plate, that is, where aligned to the surface to be cooled, and partially aligned to a second region of the cold plate, which is outside the first region. The one or more heat pipes facilitate distribution of heat from the electronic component to coolant-carrying channel sections of the cold plate located in the second region of the cold plate.

  1. 78 FR 16531 - Certain Electronic Devices for Capturing and Transmitting Images, and Components Thereof...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2013-03-15

    ... INTERNATIONAL TRADE COMMISSION [Investigation No. 337-TA-831] Certain Electronic Devices for Capturing and Transmitting Images, and Components Thereof; Commission Determination Not To Review an Initial... certain electronic devices for capturing and transmitting images, and components thereof. The complaint...

  2. XAFS and X-Ray and Electron Microscopy Investigations of Radionuclide Transformations at the Mineral-Microbe Interface

    NASA Astrophysics Data System (ADS)

    Kemner, Ken; O'Loughlin, Ed; Kelly, Shelly; Ravel, Bruce; Boyanov, Maxim; Sholto-Douglas, Deirdre; Lai, Barry; Cook, Russ; Carpenter, Everett; Harris, Vince; Nealson, Ken

    2007-02-01

    The microenvironment at and adjacent to surfaces of actively metabolizing cells, whether in a planktonic state or adhered to mineral surfaces, can be significantly different from the bulk environment. Microbial polymers (polysaccharides, DNA, RNA, and proteins), whether attached to or released from the cell, can contribute to the development of steep chemical gradients over very short distances. It is currently difficult to predict the behavior of contaminant radionuclides and metals in such microenvironments, because the chemistry there has been difficult or impossible to define. The behavior of contaminants in such microenvironments can ultimately affect their macroscopic fates. We have successfully performed a series of U LIII edge x-ray absorption fine structure (XAFS) spectroscopy, hard x-ray fluorescence (XRF) microprobe (150 nm resolution), and electron microscopy (EM) measurements on lepidocrocite thin films (˜1 micron thickness) deposited on kapton films that have been inoculated with the dissimilatory metal reducing bacterium Shewanella oneidensis MR-1 and exposed to 0.05 mM uranyl acetate under anoxic conditions. Similarly, we have performed a series of U LIII edge EXAFS measurements on lepidocrocite powders exposed to 0.05 mM uranyl acetate and exopolymeric components harvested from S. oneidensis MR-1 grown under aerobic conditions. These results demonstrate the utility of combining bulk XAFS with x-ray and electron microscopies.

  3. Shewanella oneidensis MR-1 chemotaxis proteins and electron-transport chain components essential for congregation near insoluble electron acceptors.

    PubMed

    Harris, H Wayne; El-Naggar, Mohamed Y; Nealson, Kenneth H

    2012-12-01

    Shewanella oneidensis MR-1 cells utilize a behaviour response called electrokinesis to increase their speed in the vicinity of IEAs (insoluble electron acceptors), including manganese oxides, iron oxides and poised electrodes [Harris, El-Naggar, Bretschger, Ward, Romine, Obraztsova and Nealson (2010) Proc. Natl. Acad. Sci. U.S.A. 107, 326-331]. However, it is not currently understood how bacteria remain in the vicinity of the IEA and accumulate both on the surface and in the surrounding medium. In the present paper, we provide results indicating that cells that have contacted the IEAs swim faster than those that have not recently made contact. In addition, fast-swimming cells exhibit an enhancement of swimming reversals leading to rapid non-random accumulation of cells on, and adjacent to, mineral particles. We call the observed accumulation near IEAs 'congregation'. Congregation is eliminated by the loss of a critical gene involved with EET (extracellular electron transport) (cymA, SO_4591) and is altered or eliminated in several deletion mutants of homologues of genes that are involved with chemotaxis or energy taxis in Escherichia coli. These genes include chemotactic signal transduction protein (cheA-3, SO_3207), methyl-accepting chemotaxis proteins with the Cache domain (mcp_cache, SO_2240) or the PAS (Per/Arnt/Sim) domain (mcp_pas, SO_1385). In the present paper, we report studies of S. oneidensis MR-1 that lend some insight into how microbes in this group can 'sense' the presence of a solid substrate such as a mineral surface, and maintain themselves in the vicinity of the mineral (i.e. via congregation), which may ultimately lead to attachment and biofilm formation.

  4. Electronic components embedded in a single graphene nanoribbon.

    PubMed

    Jacobse, P H; Kimouche, A; Gebraad, T; Ervasti, M M; Thijssen, J M; Liljeroth, P; Swart, I

    2017-07-25

    The use of graphene in electronic devices requires a band gap, which can be achieved by creating nanostructures such as graphene nanoribbons. A wide variety of atomically precise graphene nanoribbons can be prepared through on-surface synthesis, bringing the concept of graphene nanoribbon electronics closer to reality. For future applications it is beneficial to integrate contacts and more functionality directly into single ribbons by using heterostructures. Here, we use the on-surface synthesis approach to fabricate a metal-semiconductor junction and a tunnel barrier in a single graphene nanoribbon consisting of 5- and 7-atom wide segments. We characterize the atomic scale geometry and electronic structure by combined atomic force microscopy, scanning tunneling microscopy, and conductance measurements complemented by density functional theory and transport calculations. These junctions are relevant for developing contacts in all-graphene nanoribbon devices and creating diodes and transistors, and act as a first step toward complete electronic devices built into a single graphene nanoribbon.Adding functional electronic components to graphene nanoribbons requires precise control over their atomic structure. Here, the authors use a bottom-up approach to build a metal-semiconductor junction and a tunnel barrier directly into a single graphene nanoribbon, an exciting development for graphene-based electronic devices.

  5. Microorganisms meet solid minerals: interactions and biotechnological applications.

    PubMed

    Ng, Daphne H P; Kumar, Amit; Cao, Bin

    2016-08-01

    In natural and engineered environments, microorganisms often co-exist and interact with various minerals or mineral-containing solids. Microorganism-mineral interactions contribute significantly to environmental processes, including biogeochemical cycles in natural ecosystems and biodeterioration of materials in engineered environments. In this mini-review, we provide a summary of several key mechanisms involved in microorganism-mineral interactions, including the following: (i) solid minerals serve as substrata for biofilm development; (ii) solid minerals serve as an electron source or sink for microbial respiration; (iii) solid minerals provide microorganisms with macro or micronutrients for cell growth; and (iv) (semi)conductive solid minerals serve as extracellular electron conduits facilitating cell-to-cell interactions. We also highlight recent developments in harnessing microbe-mineral interactions for biotechnological applications.

  6. Thermoelectricity Generation and Electron-Magnon Scattering in a Natural Chalcopyrite Mineral from a Deep-Sea Hydrothermal Vent.

    PubMed

    Ang, Ran; Khan, Atta Ullah; Tsujii, Naohito; Takai, Ken; Nakamura, Ryuhei; Mori, Takao

    2015-10-26

    Current high-performance thermoelectric materials require elaborate doping and synthesis procedures, particularly in regard to the artificial structure, and the underlying thermoelectric mechanisms are still poorly understood. Here, we report that a natural chalcopyrite mineral, Cu1+x Fe1-x S2 , obtained from a deep-sea hydrothermal vent can directly generate thermoelectricity. The resistivity displayed an excellent semiconducting character, and a large thermoelectric power and high power factor were found in the low x region. Notably, electron-magnon scattering and a large effective mass was detected in this region, thus suggesting that the strong coupling of doped carriers and antiferromagnetic spins resulted in the natural enhancement of thermoelectric properties during mineralization reactions. The present findings demonstrate the feasibility of thermoelectric energy generation and electron/hole carrier modulation with natural materials that are abundant in the Earth's crust. © 2015 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  7. Effects of different radiation doses on the microhardness, superficial morphology, and mineral components of human enamel.

    PubMed

    de Barros da Cunha, Sandra Ribeiro; Fonseca, Felipe Paiva; Ramos, Pedro Augusto Minorin Mendes; Haddad, Cecília Maria Kalil; Fregnani, Eduardo Rodrigues; Aranha, Ana Cecília Corrêa

    2017-08-01

    To evaluate the effects of three different radiotherapy doses (20, 40, and 70Gy) on the microhardness, superficial morphology, and mineral content (based on Ca and P values) of three different depths of human enamel (cervical, middle, and occlusal). Thirty-four third molars were cut, separated, and prepared. Microhardness samples (n=30) were embedded in acrylic resin and then polished, and depths were delimited. Microhardness tests were performed on cervical, middle, and occlusal enamel pre- and post-radiotherapy with a load of 50g for 30s. For the scanning electron microscopy (SEM) analysis (n=4) and energy dispersive X-ray spectroscopy (EDS) (n=12), samples were fixed in a 3% glutaraldehyde solution, washed in 0.1M cacodylate solution, and dehydrated in crescent concentrations of ethanol. Microhardness data were tested for significant differences using a two-way analysis of variance (ANOVA) and Tukey's test (p<0.05), while SEM and EDS were evaluated qualitatively. The results showed a decrease in microhardness values only in the cervical enamel, regardless of the radiation dose used; no morphological or mineral change was observed. Radiotherapy can affect the microhardness values of only cervical enamel without compromising the morphological or mineral (Ca and P) content at any depth. Copyright © 2017 Elsevier Ltd. All rights reserved.

  8. Light and redox switchable molecular components for molecular electronics.

    PubMed

    Browne, Wesley R; Feringa, Ben L

    2010-01-01

    The field of molecular and organic electronics has seen rapid progress in recent years, developing from concept and design to actual demonstration devices in which both single molecules and self-assembled monolayers are employed as light-responsive components. Research in this field has seen numerous unexpected challenges that have slowed progress and the initial promise of complex molecular-based computers has not yet been realised. Primarily this has been due to the realisation at an early stage that molecular-based nano-electronics brings with it the interface between the hard (semiconductor) and soft (molecular) worlds and the challenges which accompany working in such an environment. Issues such as addressability, cross-talk, molecular stability and perturbation of molecular properties (e.g., inhibition of photochemistry) have nevertheless driven development in molecular design and synthesis as well as our ability to interface molecular components with bulk metal contacts to a very high level of sophistication. Numerous groups have played key roles in progressing this field not least teams such as those led by Whitesides, Aviram, Ratner, Stoddart and Heath. In this short review we will however focus on the contributions from our own group and those of our collaborators, in employing diarylethene based molecular components.

  9. 78 FR 32689 - Certain Portable Electronic Communications Devices, Including Mobile Phones and Components...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2013-05-31

    ..., Including Mobile Phones and Components Thereof Notice of Receipt of Complaint; Solicitation of Comments... Certain Portable Electronic Communications Devices, Including Mobile Phones and Components Thereof, DN... mobile phones and components thereof. The complaint names as respondents HTC Corporation of China and HTC...

  10. Analysis of minerals containing dissolved traces of the fluid phase components water and carbon dioxide

    NASA Technical Reports Server (NTRS)

    Freund, Friedemann

    1991-01-01

    Substantial progress has been made towards a better understanding of the dissolution of common gas/fluid phase components, notably H2O and CO2, in minerals. It has been shown that the dissolution mechanisms are significantly more complex than currently believed. By judiciously combining various solid state analytical techniques, convincing evidence was obtained that traces of dissolved gas/fluid phase components undergo, at least in part, a redox conversion by which they split into reduced H2 and and reduced C on one hand and oxidized oxygen, O(-), on the other. Analysis for 2 and C as well as for any organic molecules which may form during the process of co-segregation are still impeded by the omnipresent danger of extraneous contamination. However, the presence of O(-), an unusual oxidized form of oxygen, has been proven beyond a reasonable doubt. The presence of O(-) testifies to the fact that a redox reaction must have taken place in the solid state involving the dissolved traces of gas/fluid phase components. Detailed information on the techniques used and the results obtained are given.

  11. 77 FR 27078 - Certain Electronic Devices, Including Mobile Phones and Tablet Computers, and Components Thereof...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2012-05-08

    ... Phones and Tablet Computers, and Components Thereof; Notice of Receipt of Complaint; Solicitation of... entitled Certain Electronic Devices, Including Mobile Phones and Tablet Computers, and Components Thereof... the United States after importation of certain electronic devices, including mobile phones and tablet...

  12. Incineration and pyrolysis vs. steam gasification of electronic waste.

    PubMed

    Gurgul, Agnieszka; Szczepaniak, Włodzimierz; Zabłocka-Malicka, Monika

    2018-05-15

    Constructional complexity of items and their integration are the most distinctive features of electronic wastes. These wastes consist of mineral and polymeric materials and have high content of valuable metals that could be recovered. Elimination of polymeric components (especially epoxy resins) while leaving non-volatile mineral and metallic phases is the purpose of thermal treatment of electronic wastes. In the case of gasification, gaseous product of the process may be, after cleaning, used for energy recovery or chemical synthesis. If not melted, metals from solid products of thermal treatment of electronic waste could be recovered by hydrometallurgical processing. Three basic, high temperature ways of electronic waste processing, i.e. smelting/incineration, pyrolysis and steam gasification were shortly discussed in the paper, giving a special attention to gasification under steam, illustrated by laboratory experiments. Copyright © 2017 Elsevier B.V. All rights reserved.

  13. Pulmonary epithelial response in the rat lung to instilled Montserrat respirable dusts and their major mineral components.

    PubMed

    Housley, D G; Bérubé, K A; Jones, T P; Anderson, S; Pooley, F D; Richards, R J

    2002-07-01

    The Soufriere Hills, a stratovolcano on Montserrat, started erupting in July 1995, producing volcanic ash, both from dome collapse pyroclastic flows and phreatic explosions. The eruptions/ash resuspension result in high concentrations of suspended particulate matter in the atmosphere, which includes cristobalite, a mineral implicated in respiratory disorders. To conduct toxicological studies on characterised samples of ash, together with major components of the dust mixture (anorthite, cristobalite), and a bioreactive mineral control (DQ12 quartz). Rats were challenged with a single mass (1 mg) dose of particles via intratracheal instillation and groups sacrificed at one, three, and nine weeks. Acute bioreactivity of the particles was assessed by increases in lung permeability and inflammation, changes in epithelial cell markers, and increase in the size of bronchothoracic lymph nodes. Data indicated that respirable ash derived from pyroclastic flows (20.1% cristobalite) or phreatic explosion (8.6% cristobalite) had minimal bioreactivity in the lung. Anorthite showed low bioreactivity, in contrast to pure cristobalite, which showed progressive increases in lung damage. Results suggests that either the percentage mass of cristobalite particles present in Montserrat ash was not sufficient as a catalyst in the lung environment, or its surface reactivity was masked by the non-reactive volcanic glass components during the process of ash formation.

  14. Improved model for detection of homogeneous production batches of electronic components

    NASA Astrophysics Data System (ADS)

    Kazakovtsev, L. A.; Orlov, V. I.; Stashkov, D. V.; Antamoshkin, A. N.; Masich, I. S.

    2017-10-01

    Supplying the electronic units of the complex technical systems with electronic devices of the proper quality is one of the most important problems for increasing the whole system reliability. Moreover, for reaching the highest reliability of an electronic unit, the electronic devices of the same type must have equal characteristics which assure their coherent operation. The highest homogeneity of the characteristics is reached if the electronic devices are manufactured as a single production batch. Moreover, each production batch must contain homogeneous raw materials. In this paper, we propose an improved model for detecting the homogeneous production batches of shipped lot of electronic components based on implementing the kurtosis criterion for the results of non-destructive testing performed for each lot of electronic devices used in the space industry.

  15. Characterization of two distinctly different mineral-related proteins from the teeth of the Camarodont sea urchin Lytechinus variegatus: Specificity of function with relation to mineralization

    NASA Astrophysics Data System (ADS)

    Veis, A.; Alvares, K.; Dixit, S. N.; Robach, J. S.; Stock, S. R.

    2009-06-01

    The majority of the mineral phase of the Lytechinus variegatus tooth is comprised of magnesium containing calcite crystal elements, collectively arranged so that they appear as a single crystal under polarized light, as well as under X-ray or electron irradiation. However, the crystal elements are small, and in spite of the common alignment of their crystal axes, are not the same size or shape in different parts of the tooth. The toughness of the tooth structure arises from the fact that it is a composite in which the crystals are coated with surface layers of organic matter that probably act to inhibit crack formation and elongation. In the growth region the organic components represent a greater part of the tooth structure. In the most heavily mineralized adoral region the primary plates fuse with inter-plate pillars. Using Scanning Electron Microscopy; TOF-SIMS mapping of the characteristic amino acids of the mineral related proteins; and isolation and characterization of the mineral-protected protein we report that the late-forming inter-plate pillars had more than a three-fold greater Mg content than the primary plates. Furthermore, the aspartic acid content of the mineralrelated protein was highest in the high Mg pillars whereas the mineral-protected protein of the primary plates was richer in glutamic acid content.These results suggest that the Asp-rich protein(s) is important for formation of the late developing inter-plate pillars that fuse the primary plates and increase the stiffness of the most mature tooth segment. Supported by NIDCR Grant DE R01-01374 to AV.

  16. Approach to In Situ Component Level Electronics Assembly Repair (CLEAR) for Constellation

    NASA Technical Reports Server (NTRS)

    Struk, Peter M.; Oeftering, Richard C.

    2010-01-01

    Maintenance resupply is a significant issue for long duration space missions. Currently, the International Space Station (ISS) approaches maintenance primarily around replaceable modules called Orbital Replacement Units (ORU). While swapping out ORUs has served the ISS well keeping crew time for maintenance to a minimum, this approach assumes a substantial logistics capacity to provide replacement ORUs and return ORUs to Earth for repair. The ORUs used for ISS require relatively large blocks of replacement hardware even though the actual failed component may be several orders of magnitude smaller. The Component Level Electronics Assembly Repair (CLEAR) task was created to explore electronics repair down to the component level for future space missions. From 2006 to 2009, CLEAR was an activity under the Supportability project of the Exploration Technology Development Program. This paper describes the activities of CLEAR including making a case for component-level electronics repair, examination of current terrestrial repair hardware, and potential repair needs. Based on those needs, the CLEAR team proposes an architecture for an in-situ repair capability aboard a spacecraft or habitat. Additionally, this paper discusses recent progress toward developing in-space repair capabilities--including two spaceflight experiments-- and presents technology concepts which could help enable or benefit the same.

  17. 78 FR 71643 - Certain Wireless Consumer Electronics Devices and Components Thereof; Commission Determination To...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2013-11-29

    ... Electronics Devices and Components Thereof; Commission Determination To Review in Part A Final Initial... sale within the United States after importation of certain wireless consumer electronics devices and... Electronics, Inc. of Seoul, Korea and LG Electronics U.S.A., Inc. of Englewood Cliffs, New Jersey...

  18. Component-Level Electronic-Assembly Repair (CLEAR) Operational Concept

    NASA Technical Reports Server (NTRS)

    Oeftering, Richard C.; Bradish, Martin A.; Juergens, Jeffrey R.; Lewis, Michael J.; Vrnak, Daniel R.

    2011-01-01

    This Component-Level Electronic-Assembly Repair (CLEAR) Operational Concept document was developed as a first step in developing the Component-Level Electronic-Assembly Repair (CLEAR) System Architecture (NASA/TM-2011-216956). The CLEAR operational concept defines how the system will be used by the Constellation Program and what needs it meets. The document creates scenarios for major elements of the CLEAR architecture. These scenarios are generic enough to apply to near-Earth, Moon, and Mars missions. The CLEAR operational concept involves basic assumptions about the overall program architecture and interactions with the CLEAR system architecture. The assumptions include spacecraft and operational constraints for near-Earth orbit, Moon, and Mars missions. This document addresses an incremental development strategy where capabilities evolve over time, but it is structured to prevent obsolescence. The approach minimizes flight hardware by exploiting Internet-like telecommunications that enables CLEAR capabilities to remain on Earth and to be uplinked as needed. To minimize crew time and operational cost, CLEAR exploits offline development and validation to support online teleoperations. Operational concept scenarios are developed for diagnostics, repair, and functional test operations. Many of the supporting functions defined in these operational scenarios are further defined as technologies in NASA/TM-2011-216956.

  19. The nanometre-scale physiology of bone: steric modelling and scanning transmission electron microscopy of collagen–mineral structure

    PubMed Central

    Alexander, Benjamin; Daulton, Tyrone L.; Genin, Guy M.; Lipner, Justin; Pasteris, Jill D.; Wopenka, Brigitte; Thomopoulos, Stavros

    2012-01-01

    The nanometre-scale structure of collagen and bioapatite within bone establishes bone's physical properties, including strength and toughness. However, the nanostructural organization within bone is not well known and is debated. Widely accepted models hypothesize that apatite mineral (‘bioapatite’) is present predominantly inside collagen fibrils: in ‘gap channels’ between abutting collagen molecules, and in ‘intermolecular spaces’ between adjacent collagen molecules. However, recent studies report evidence of substantial extrafibrillar bioapatite, challenging this hypothesis. We studied the nanostructure of bioapatite and collagen in mouse bones by scanning transmission electron microscopy (STEM) using electron energy loss spectroscopy and high-angle annular dark-field imaging. Additionally, we developed a steric model to estimate the packing density of bioapatite within gap channels. Our steric model and STEM results constrain the fraction of total bioapatite in bone that is distributed within fibrils at less than or equal to 0.42 inside gap channels and less than or equal to 0.28 inside intermolecular overlap regions. Therefore, a significant fraction of bone's bioapatite (greater than or equal to 0.3) must be external to the fibrils. Furthermore, we observe extrafibrillar bioapatite between non-mineralized collagen fibrils, suggesting that initial bioapatite nucleation and growth are not confined to the gap channels as hypothesized in some models. These results have important implications for the mechanics of partially mineralized and developing tissues. PMID:22345156

  20. 78 FR 34132 - Certain Portable Electronic Communications Devices, Including Mobile Phones and Components...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2013-06-06

    ... INTERNATIONAL TRADE COMMISSION [Docket No 2958] Certain Portable Electronic Communications Devices, Including Mobile Phones and Components Thereof; Correction to Notice of Receipt of Complaint; Solicitation... of complaint entitled Certain Portable Electronic Communications Devices, Including Mobile Phones and...

  1. 3D calcite heterostructures for dynamic and deformable mineralized matrices

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Yi, Jaeseok; Wang, Yucai; Jiang, Yuanwen

    Scales are rooted in soft tissues, and are regenerated by specialized cells. The realization of dynamic synthetic analogues with inorganic materials has been a significant challenge, because the abiological regeneration sites that could yield deterministic growth behavior are hard to form. Here we overcome this fundamental hurdle by constructing a mutable and deformable array of three-dimensional calcite heterostructures that are partially locked in silicone. Individual calcite crystals exhibit asymmetrical dumbbell shapes and are prepared by a parallel tectonic approach under ambient conditions. Furthermore, the silicone matrix immobilizes the epitaxial nucleation sites through self-templated cavities, which enables symmetry breaking in reactionmore » dynamics and scalable manipulation of the mineral ensembles. With this platform, we devise several mineral-enabled dynamic surfaces and interfaces. For example, we show that the induced growth of minerals yields localized inorganic adhesion for biological tissue and reversible focal encapsulation for sensitive components in flexible electronics.« less

  2. 3D calcite heterostructures for dynamic and deformable mineralized matrices

    DOE PAGES

    Yi, Jaeseok; Wang, Yucai; Jiang, Yuanwen; ...

    2017-09-11

    Scales are rooted in soft tissues, and are regenerated by specialized cells. The realization of dynamic synthetic analogues with inorganic materials has been a significant challenge, because the abiological regeneration sites that could yield deterministic growth behavior are hard to form. Here we overcome this fundamental hurdle by constructing a mutable and deformable array of three-dimensional calcite heterostructures that are partially locked in silicone. Individual calcite crystals exhibit asymmetrical dumbbell shapes and are prepared by a parallel tectonic approach under ambient conditions. Furthermore, the silicone matrix immobilizes the epitaxial nucleation sites through self-templated cavities, which enables symmetry breaking in reactionmore » dynamics and scalable manipulation of the mineral ensembles. With this platform, we devise several mineral-enabled dynamic surfaces and interfaces. For example, we show that the induced growth of minerals yields localized inorganic adhesion for biological tissue and reversible focal encapsulation for sensitive components in flexible electronics.« less

  3. Chemical Bonding in Sulfide Minerals

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Vaughan, David J.; Rosso, Kevin M.

    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 andmore » 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

  4. Printing Electronic Components from Copper-Infused Ink and Thermoplastic Mediums

    NASA Astrophysics Data System (ADS)

    Flowers, Patrick F.

    The demand for printable electronics has sharply increased in recent years and is projected to continue to rise. Unfortunately, electronic materials which are suitable for desired applications while being compatible with available printing techniques are still often lacking. This thesis addresses two such challenging areas. In the realm of two-dimensional ink-based printing of electronics, a major barrier to the realization of printable computers that can run programs is the lack of a solution-coatable non-volatile memory with performance metrics comparable to silicon-based devices. To address this deficiency, I developed a nonvolatile memory based on Cu-SiO2 core-shell nanowires that can be printed from solution and exhibits on-off ratios of 106, switching speeds of 50 ns, a low operating voltage of 2 V, and operates for at least 104 cycles without failure. Each of these metrics is similar to or better than Flash memory (the write speed is 20 times faster than Flash). Memory architectures based on the individual memory cells demonstrated here could enable the printing of the more complex, embedded computing devices that are expected to make up an internet of things. Recently, the exploration of three-dimensional printing techniques to fabricate electronic materials began. A suitable general-purpose conductive thermoplastic filament was not available, however. In this work I examine the current state of conductive thermoplastic filaments, including a newly-released highly conductive filament that my lab has produced which we call Electrifi. I focus on the use of dual-material fused filament fabrication (FFF) to 3D print electronic components (conductive traces, resistors, capacitors, inductors) and circuits (a fully-printed high-pass filter). The resistivity of traces printed from conductive thermoplastic filaments made with carbon-black, graphene, and copper as conductive fillers was found to be 12, 0.78, and 0.014 ohm cm, respectively, enabling the creation of

  5. Application of Quantitative Analytical Electron Microscopy to the Mineral Content of Insect Cuticle

    NASA Astrophysics Data System (ADS)

    Rasch, Ron; Cribb, Bronwen W.; Barry, John; Palmer, Christopher M.

    2003-04-01

    Quantification of calcium in the cuticle of the fly larva Exeretonevra angustifrons was undertaken at the micron scale using wavelength dispersive X-ray microanalysis, analytical standards, and a full matrix correction. Calcium and phosphorus were found to be present in the exoskeleton in a ratio that indicates amorphous calcium phosphate. This was confirmed through electron diffraction of the calcium-containing tissue. Due to the pragmatic difficulties of measuring light elements, it is not uncommon in the field of entomology to neglect the use of matrix corrections when performing microanalysis of bulk insect specimens. To determine, firstly, whether such a strategy affects the outcome and secondly, which matrix correction is preferable, phi-rho (z) and ZAF matrix corrections were contrasted with each other and without matrix correction. The best estimate of the mineral phase was found to be given by using the phi-rho (z) correction. When no correction was made, the ratio of Ca to P fell outside the range for amorphous calcium phosphate, possibly leading to flawed interpretation of the mineral form when used on its own.

  6. Pulmonary epithelial response in the rat lung to instilled Montserrat respirable dusts and their major mineral components

    PubMed Central

    Housley, D; Berube, K; Jones, T; Anderson, S; Pooley, F; Richards, R

    2002-01-01

    Background: The Soufriere Hills, a stratovolcano on Montserrat, started erupting in July 1995, producing volcanic ash, both from dome collapse pyroclastic flows and phreatic explosions. The eruptions/ash resuspension result in high concentrations of suspended particulate matter in the atmosphere, which includes cristobalite, a mineral implicated in respiratory disorders. Aims: To conduct toxicological studies on characterised samples of ash, together with major components of the dust mixture (anorthite, cristobalite), and a bioreactive mineral control (DQ12 quartz). Methods: Rats were challenged with a single mass (1 mg) dose of particles via intratracheal instillation and groups sacrificed at one, three, and nine weeks. Acute bioreactivity of the particles was assessed by increases in lung permeability and inflammation, changes in epithelial cell markers, and increase in the size of bronchothoracic lymph nodes. Results: Data indicated that respirable ash derived from pyroclastic flows (20.1% cristobalite) or phreatic explosion (8.6% cristobalite) had minimal bioreactivity in the lung. Anorthite showed low bioreactivity, in contrast to pure cristobalite, which showed progressive increases in lung damage. Conclusion: Results suggests that either the percentage mass of cristobalite particles present in Montserrat ash was not sufficient as a catalyst in the lung environment, or its surface reactivity was masked by the non-reactive volcanic glass components during the process of ash formation. PMID:12107295

  7. DEVELOPMENT OF MULTI-PHASE AND MULTI-COMPONENT FLOW MODEL WITH REACTION IN POROUS MEDIA FOR RISK ASSESSMENT ON SOIL CONTAMINATION DUE TO MINERAL OIL

    NASA Astrophysics Data System (ADS)

    Sakamoto, Yasuhide; Nishiwaki, Junko; Hara, Junko; Kawabe, Yoshishige; Sugai, Yuichi; Komai, Takeshi

    In late years, soil contamination due to mineral oil in vacant lots of oil factory and oil field has become obvious. Measure for soil contamina tion and risk assessment are neces sary for sustainable development of industrial activity. Especially, in addition to contaminated sites, various exposure paths for human body such as well water, soil and farm crop are supposed. So it is very important to comprehend the transport phenomena of contaminated material under the environments of soil and ground water. In this study, mineral oil as c ontaminated material consisting of mu lti-component such as aliphatic and aromatic series was modeled. Then numerical mode l for transport phenomena in surface soil and aquifer was constructed. On the basis of modeling for mineral oil, our numerical model consists of three-phase (oil, water and gas) forty three-component. This numerical model becomes base program for risk assessment system on soil contamination due to mineral oil. Using this numerical model, we carried out some numerical simulation for a laboratory-scale experiment on oil-water multi-phase flow. Relative permeability that dominate flow behavior in multi-phase condition was formulated and the validity of the numerical model developed in this study was considered.

  8. Microstructural Analysis of Ti-6Al-4V Components Made by Electron Beam Additive Manufacturing

    NASA Astrophysics Data System (ADS)

    Coleman, Rashadd L.

    Electron Beam Additive Manufacturing (EBAM) is a relatively new additive manufacturing (AM) technology that uses a high-energy electron beam to melt and fuse powders to build full-density parts in a layer by layer fashion. EBAM can fabricate metallic components, particularly, of complex shapes, in an efficient and cost-effective manner compared to conventional manufacturing means. EBAM is an enabling technology for rapid manufacturing (RM) of metallic components, and thus, can efficiently integrate the design and manufacturing of aerospace components. However, EBAM for aerospace-related applications remain limited because the effect of the EBAM process on part characteristics is not fully understood. In this study, various techniques including microhardness, optical microscopy (OM), X-ray diffraction (XRD), Scanning Electron Microscopy (SEM), and electron backscatter diffraction (EBSD) were used to characterize Ti-6Al-4V components processed using EBAM. The results were compared to Ti-6Al-4V components processed using conventional techniques. In this study it is shown that EBAM built Ti-64 components have increased hardness, elastic modulus, and yield strength compared to wrought Ti-6Al-4V. Further, it is also shown in this study that the horizontal build EBAM Ti-6Al-4V has increased hardness, elastic modulus, and yield strength compared to vertical build EBAM due to a preferential growth of the beta phase.

  9. 27 CFR 73.11 - What are the required components and controls for acceptable electronic signatures?

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ... components and controls for acceptable electronic signatures? 73.11 Section 73.11 Alcohol, Tobacco Products and Firearms ALCOHOL AND TOBACCO TAX AND TRADE BUREAU, DEPARTMENT OF THE TREASURY (CONTINUED) PROCEDURES AND PRACTICES ELECTRONIC SIGNATURES; ELECTRONIC SUBMISSION OF FORMS Electronic Signatures § 73.11...

  10. Phenomenological characteristic of the electron component in gamma-quanta initiated showers

    NASA Technical Reports Server (NTRS)

    Nikolsky, S. I.; Stamenov, J. N.; Ushev, S. Z.

    1985-01-01

    The phenomenological characteristics of the electron component in showers initiated by primary gamma-quanta were analyzed on the basis of the Tien Shan experimental data. It is shown that the lateral distribution of the electrons ion gamma-quanta initiated showers can be described with NKG - function with age parameters bar S equals 0, 76 plus or minus 0, 02, different from the same parameter for normal showers with the same size bar S equals 0, 85 plus or minus 0, 01. The lateral distribution of the correspondent electron energy flux in gamma-quanta initiated showers is steeper as in normal cosmic ray showers.

  11. Carrier generation and electronic properties of a single-component pure organic metal

    NASA Astrophysics Data System (ADS)

    Kobayashi, Yuka; Terauchi, Takeshi; Sumi, Satoshi; Matsushita, Yoshitaka

    2017-01-01

    Metallic conduction generally requires high carrier concentration and wide bandwidth derived from strong orbital interaction between atoms or molecules. These requisites are especially important in organic compounds because a molecule is fundamentally an insulator; only multi-component salts with strong intermolecular interaction--namely, only charge transfer complexes and conducting polymers--have demonstrated intrinsic metallic behaviour. Herein we report a single-component electroactive molecule, zwitterionic tetrathiafulvalene(TTF)-extended dicarboxylate radical (TED), exhibiting metallic conduction even at low temperatures. TED exhibits d.c. conductivities of 530 S cm-1 at 300 K and 1,000 S cm-1 at 50 K with copper-like electronic properties. Spectroscopic and theoretical investigations of the carrier-generation mechanism and the electronic states of this single molecular species reveal a unique electronic structure with a spin-density gradient in the extended TTF moieties that becomes, in itself, a metallic state.

  12. Petrological features of selected components of the Cergowa sandstones (Outer Carpathians) recorded by scanning electron microscopy - preliminary study

    NASA Astrophysics Data System (ADS)

    Pszonka, Joanna

    2017-11-01

    The scanning electron microscope analysis of the Cergowa sandstones brings new data on their petrological features and chemical composition. Previous work in standard petrographic examination, e.g. polarising (PL) or cathodoluminescence (CL) microscopy, displayed limited information on grain surface topography and only assumptions to their geochemistry. Both identification and characterisation of minerals are fundamental in the progress of mining and minerals processing systems. Detrital grains of the Cergowa sandstones are bound by calcite and dolomitic cement and commonly corroded by diagenetic fluids, however, in varying degrees, which is illustrated here by feldspar, quartz and dolomite minerals. Dissolution processes of marginal parts of these mineral grains resulted in corrosion, which increased the contact surface between the grains and the cement. The difference in resistance to these processes was observed not only among distinct groups of minerals, but also within the group of feldspars: between K-feldspars and minerals of plagioclase. That combination resulted in exceptionally strong cementation of the Cergowa sandstones, which is expressed by their high hardness and resistance to abrasion, freezing, and thawing. Inherent parameters of sandstones are characterised by their petrographical properties.

  13. Growth of Iron(III)-Reducing Bacteria on Clay Minerals as the Sole Electron Acceptor and Comparison of Growth Yields on a Variety of Oxidized Iron Forms†

    PubMed Central

    Kostka, Joel E.; Dalton, Dava D.; Skelton, Hayley; Dollhopf, Sherry; Stucki, Joseph W.

    2002-01-01

    Smectite clay minerals are abundant in soils and sediments worldwide and are typically rich in Fe. While recent investigations have shown that the structural Fe(III) bound in clay minerals is reduced by microorganisms, previous studies have not tested growth with clay minerals as the sole electron acceptor. Here we have demonstrated that a pure culture of Shewanella oneidensis strain MR-1 as well as enrichment cultures of Fe(III)-reducing bacteria from rice paddy soil and subsurface sediments are capable of conserving energy for growth with the structural Fe(III) bound in smectite clay as the sole electron acceptor. Pure cultures of S. oneidensis were used for more detailed growth rate and yield experiments on various solid- and soluble-phase electron acceptors [smectite, Fe(III) oxyhydroxide FeOOH, Fe(III) citrate, and oxygen] in the same minimal medium. Growth was assessed as direct cell counts or as an increase in cell carbon (measured as particulate organic carbon). Cell counts showed that similar growth of S. oneidensis (108 cells ml−1) occurred with smectitic Fe(III) and on other Fe forms [amorphous Fe(III) oxyhydroxide, and Fe citrate] or oxygen as the electron acceptor. In contrast, cell yields of S. oneidensis measured as the increase in cell carbon were similar on all Fe forms tested while yields on oxygen were five times higher, in agreement with thermodynamic predictions. Over a range of particle loadings (0.5 to 4 g liter−1), the increase in cell number was highly correlated to the amount of structural Fe in smectite reduced. From phylogenetic analysis of the complete 16S rRNA gene sequences, a predominance of clones retrieved from the clay mineral-reducing enrichment cultures were most closely related to the low-G+C gram-positive members of the Bacteria (Clostridium and Desulfitobacterium) and the δ-Proteobacteria (members of the Geobacteraceae). Results indicate that growth with smectitic Fe(III) is similar in magnitude to that with Fe

  14. Energy Filtering Transmission Electron Tomography (EFTET) of Bacteria-Mineral Associations within the Deep sea Hydrothermal Vent Shrimp Rimicaris exoculata.

    NASA Astrophysics Data System (ADS)

    Anderson, L. M.; Halary, S.; Lechaire, J.; Frébourg, G.; Boudier, T.; Zbinden, M.; Laval, J.; Marco, S.; Gaill, F.

    2007-12-01

    The chemical and temperature conditions around deep sea hydrothermal vents are both dynamic and extreme, yet the shrimp Rimicaris exoculata flourishes around these environments on the Mid--Atlantic Ridge (MAR). Epibiotic bacteria and minerals found within the branchial chamber (BC) of the shrimp are of great interest in the search for a chemical model for the Rainbow MAR hydrothermal vent site. Here we examine the close, three-- dimensional (3D) relationship between bacteria (on the inner surface of the BC wall) and the minerals that surround them. The morphology and chemistry of the minerals were analysed by Energy filtering Transmission Electron Microscopy (EFTEM, on a LEO--912 microscope) and X-ray Nano-analysis (EDXN, on a JEOL--2010 FEG microscope) respectively, and the 3D organization was determined by Transmission Electron Tomography (TET) and EFTET. Consecutive thin and semi--thin sections of 50--80nm (for EFTEM and EDXN) and 200--250nm (for TEM and EFTET) were cut through the BC cuticle and mounted on standard microscope grids. Sections were observed initially for morphology, to find broad relationships between bacteria and minerals. EFTET series acquisition was performed under cryo-conditions (-175°C) using a LEO-912 microscope. At each position of interest four tilt series were taken at two degree increments between -55° and +55° at various energy--losses: 1) zero--loss (ref); 2) 720 eV, 3) 690 eV and 4) 670 eV, to reconstruct the 3D location of iron. Tilted series were obtained using the ESIvision program (Soft--Imaging Software, Münster, Germany) with additional in--house scripts for automated acquisition. The 3D EFTET reconstruction volume was produced from the four tilted series using recently developed EFTET--J software (http://www.snv.jussieu.fr/~wboudier/softs.html). In many cases the observed minerals exhibit a sharp boundary against the bacteria, often with a substantial void between bacterial membrane/cell wall and mineral boundary. Mineral

  15. In vitro enzymatic reduction kinetics of mineral oxides by membrane fractions from Shewanella oneidensis MR-1

    NASA Astrophysics Data System (ADS)

    Ruebush, Shane S.; Icopini, Gary A.; Brantley, Susan L.; Tien, Ming

    2006-01-01

    This study documents the first example of in vitro solid-phase mineral oxide reduction by enzyme-containing membrane fractions. Previous in vitro studies have only reported the reduction of aqueous ions. Total membrane (TM) fractions from iron-grown cultures of Shewanella oneidensis MR-1 were isolated and shown to catalyze the reduction of goethite, hematite, birnessite, and ramsdellite/pyrolusite using formate. In contrast, nicotinamide adenine dinucleotide (NADH) and succinate cannot function as electron donors. The significant implications of observations related to this cell-free system are: (i) both iron and manganese mineral oxides are reduced by the TM fraction, but aqueous U(VI) is not; (ii) TM fractions from anaerobically grown, but not aerobically grown, cells can reduce the mineral oxides; (iii) electron shuttles and iron chelators are not needed for this in vitro reduction, documenting conclusively that reduction can occur by direct contact with the mineral oxide; (iv) electron shuttles and EDTA stimulate the in vitro Fe(III) reduction, documenting that exogenous molecules can enhance rates of enzymatic mineral reduction; and (v) multiple membrane components are involved in solid-phase oxide reduction. The membrane fractions, consisting of liposomes of cytoplasmic and outer membrane segments, contain at least 100 proteins including the enzyme that oxidizes formate, formate dehydrogenase. Mineral oxide reduction was inhibited by the addition of detergent Triton X-100, which solubilizes membranes and their associated proteins, consistent with the involvement of multiple electron carriers that are disrupted by detergent addition. In contrast, formate dehydrogenase activity was not inhibited by Triton X-100. The addition of anthraquinone-2,6-disulfonate (AQDS) and menaquinone-4 was unable to restore activity; however, menadione (MD) restored 33% of the activity. The addition of AQDS and MD to reactions without added detergent increased the rate of goethite

  16. Boundaries of intergrowths between mineral individuals: A zone of secondary mineral formation in aggregates

    NASA Astrophysics Data System (ADS)

    Brodskaya, R. L.; Bil'Skaya, I. V.; Lyakhnitskaya, V. D.; Markovsky, B. A.; Sidorov, E. G.

    2007-12-01

    Intergrowth boundaries between mineral individuals in dunite of the Gal’moenan massif in Koryakia was studied in terms of crystal morphology, crystal optics, and ontogenesis. The results obtained allowed us to trace the staged formation of olivine and chromite and four generations of these minerals. Micro-and nanotopography of boundary surfaces between intergrown mineral individuals of different generations was examined with optic, electron, and atomic force microscopes. The boundaries between mineral individuals of different generations are distinguished by their microsculpture for both olivine and chromite grains. Both minerals demonstrate a compositional trend toward refinement from older to younger generations. The decrease in the iron mole fraction in olivine and chromite is accompanied by the crystallization of magnetite along weakened zones in olivine of the first generation and as outer rims around the chromite grains of the second generation observable under optic and electronic microscopes. The subsequent refinement of chromite results in the release of PGE from its lattice, as established by atomic power microscopy. The newly formed PGM are localized at the boundaries between mineral individuals and, thus, mark a special stage in the ontogenetic evolution of mineral aggregates. Further recrystallization is expressed in the spatial redistribution of grain boundaries and the formation of monomineralic intergrowth boundaries, i.e., the glomerogranular structure of rock and substructures of PGM, chromite, and olivine grains as intermediate types of organization of the granular assemblies in the form of reticulate, chain, and cellular structures and substructures of aggregates.

  17. Metabolically healthy/unhealthy components may modify bone mineral density in obese people.

    PubMed

    Mirzababaei, Atieh; Mirzaei, Khadijeh; Khorrami-Nezhad, Leila; Maghbooli, Zhila; Keshavarz, Seyed Ali

    2017-10-29

    Link between obesity and bone health is controversial. It seems that maybe the difference in metabolic status leads to this difference. We studied relation between metabolically healthy/unhealthy components with bone mineral density. Results showed metabolically unhealthy obesity (MUHO) phenotypes have better bone status at hip site than metabolically healthy obesity (MHO). Also, component metabolic can effect on BMD in different sites. This cross-sectional study aimed to compare total BMD and L-L4 BMD in MHO and MUHO base on Karelis criteria. We enrolled 272 Iranian obese women and men (BMI ≥ 30). According to Karelis criteria, the participants were grouped base to MHO and MUHO. The body composition and BMD were assessed for all cases. Serum HDL-C, LDL-C, total cholesterol, triglyceride (TG), fasting blood glucose, homeostatic model assessment-insulin resistance (HOMA-IR), and hypersensitive C-reactive protein (hs-CRP) levels were quantified by ELISA method. Our results demonstrate MUHO phenotype have high total BMD more than MHO (P = 0.01, CI = 0.12 to 0.21). Also, the results of logistic regression analysis showed MUHO have strongly associated with total BMD (β = -0.42, CI = - 0.31 to - 0.04, P = 0.009), but did not affected L2-L4 BMD (β = - 0.09, CI = - 0.14 to 0.08, P = 0.578); this represents that there was discordance in MUHO subjects. Our evidence implicated that HOMA-IR, high level serum TG, hs-CRP, and low level serum HDL had mediatory effect on relationship between obesity and high BMD at the hip region in MUHO subjects (P < 0.05). Present evidence indicates that, could be a novel link between difference in MUH phenotype and MH phenotype with bone status. Also, component metabolic can effect on BMD in different sites.

  18. A new active solder for joining electronic components

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    SMITH,RONALD W.; VIANCO,PAUL T.; HERNANDEZ,CYNTHIA L.

    Electronic components and micro-sensors utilize ceramic substrates, copper and aluminum interconnect and silicon. The joining of these combinations require pre-metallization such that solders with fluxes can wet such combinations of metals and ceramics. The paper will present a new solder alloy that can bond metals, ceramics and composites. The alloy directly wets and bonds in air without the use flux or premetallized layers. The paper will present typical processing steps and joint microstructures in copper, aluminum, aluminum oxide, aluminum nitride, and silicon joints.

  19. Mineralization of collagen may occur on fibril surfaces: evidence from conventional and high-voltage electron microscopy and three-dimensional imaging

    NASA Technical Reports Server (NTRS)

    Landis, W. J.; Hodgens, K. J.; Song, M. J.; Arena, J.; Kiyonaga, S.; Marko, M.; Owen, C.; McEwen, B. F.

    1996-01-01

    The interaction between collagen and mineral crystals in the normally calcifying leg tendons from the domestic turkey, Meleagris gallopavo, has been investigated at an ultrastructural level with conventional and high-voltage electron microscopy, computed tomography, and three-dimensional image reconstruction methods. Specimens treated by either aqueous or anhydrous techniques and resin-embedded were appropriately sectioned and regions of early tendon mineralization were photographed. On the basis of individual photomicrographs, stereoscopic pairs of images, and tomographic three-dimensional image reconstructions, platelet-shaped crystals may be demonstrated for the first time in association with the surface of collagen fibrils. Mineral is also observed in closely parallel arrays within collagen hole and overlap zones. The mineral deposition at these spatially distinct locations in the tendon provides insight into possible means by which calcification is mediated by collagen as a fundamental event in skeletal and dental formation among vertebrates.

  20. Component-Level Electronic-Assembly Repair (CLEAR) System Architecture

    NASA Technical Reports Server (NTRS)

    Oeftering, Richard C.; Bradish, Martin A.; Juergens, Jeffrey R.; Lewis, Michael J.; Vrnak, Daniel R.

    2011-01-01

    This document captures the system architecture for a Component-Level Electronic-Assembly Repair (CLEAR) capability needed for electronics maintenance and repair of the Constellation Program (CxP). CLEAR is intended to improve flight system supportability and reduce the mass of spares required to maintain the electronics of human rated spacecraft on long duration missions. By necessity it allows the crew to make repairs that would otherwise be performed by Earth based repair depots. Because of practical knowledge and skill limitations of small spaceflight crews they must be augmented by Earth based support crews and automated repair equipment. This system architecture covers the complete system from ground-user to flight hardware and flight crew and defines an Earth segment and a Space segment. The Earth Segment involves database management, operational planning, and remote equipment programming and validation processes. The Space Segment involves the automated diagnostic, test and repair equipment required for a complete repair process. This document defines three major subsystems including, tele-operations that links the flight hardware to ground support, highly reconfigurable diagnostics and test instruments, and a CLEAR Repair Apparatus that automates the physical repair process.

  1. TomoMiner and TomoMinerCloud: A software platform for large-scale subtomogram structural analysis

    PubMed Central

    Frazier, Zachary; Xu, Min; Alber, Frank

    2017-01-01

    SUMMARY Cryo-electron tomography (cryoET) captures the 3D electron density distribution of macromolecular complexes in close to native state. With the rapid advance of cryoET acquisition technologies, it is possible to generate large numbers (>100,000) of subtomograms, each containing a macromolecular complex. Often, these subtomograms represent a heterogeneous sample due to variations in structure and composition of a complex in situ form or because particles are a mixture of different complexes. In this case subtomograms must be classified. However, classification of large numbers of subtomograms is a time-intensive task and often a limiting bottleneck. This paper introduces an open source software platform, TomoMiner, for large-scale subtomogram classification, template matching, subtomogram averaging, and alignment. Its scalable and robust parallel processing allows efficient classification of tens to hundreds of thousands of subtomograms. Additionally, TomoMiner provides a pre-configured TomoMinerCloud computing service permitting users without sufficient computing resources instant access to TomoMiners high-performance features. PMID:28552576

  2. Mid-Infrared Spectroscopy Analysis of the Effects of Erbium, Chromium:Yattrium-Scandium-Gallium-Garnet (Er,Cr:YSGG) Laser Irradiation on Bone Mineral and Organic Components.

    PubMed

    Benetti, Carolina; Ana, Patricia Aparecida; Bachmann, Luciano; Zezell, Denise Maria

    2015-12-01

    The effects of varying the energy density of a high-intensity erbium, chromium: yttrium-scandium-gallium-garnet (Er,Cr:YSGG) laser on the mineral and organic components of bone tissue were evaluated using Fourier transform infrared spectroscopy. Bone samples obtained from the tibias of rabbits were irradiated with five energy densities (3, 6, 8, 12, and 15 J/cm(2)), and the effects on the carbonate to phosphate ratio and in the organic components were compared with those of nonirradiated samples. The increased temperature during the laser irradiation was also measured using infrared thermography to relate the observed spectral changes to the laser thermal effects. The analyses of the infrared spectra suggests that the irradiation with Er,Cr:YSGG promoted changes in bone tissue in both the mineral and organic components that depend on the laser energy density, pointing to the importance of using the proper energy density in clinical procedures.

  3. Vibrational Analysis of Engine Components Using Neural-Net Processing and Electronic Holography

    NASA Technical Reports Server (NTRS)

    Decker, Arthur J.; Fite, E. Brian; Mehmed, Oral; Thorp, Scott A.

    1997-01-01

    The use of computational-model trained artificial neural networks to acquire damage specific information from electronic holograms is discussed. A neural network is trained to transform two time-average holograms into a pattern related to the bending-induced-strain distribution of the vibrating component. The bending distribution is very sensitive to component damage unlike the characteristic fringe pattern or the displacement amplitude distribution. The neural network processor is fast for real-time visualization of damage. The two-hologram limit makes the processor more robust to speckle pattern decorrelation. Undamaged and cracked cantilever plates serve as effective objects for testing the combination of electronic holography and neural-net processing. The requirements are discussed for using finite-element-model trained neural networks for field inspections of engine components. The paper specifically discusses neural-network fringe pattern analysis in the presence of the laser speckle effect and the performances of two limiting cases of the neural-net architecture.

  4. Vibrational Analysis of Engine Components Using Neural-Net Processing and Electronic Holography

    NASA Technical Reports Server (NTRS)

    Decker, Arthur J.; Fite, E. Brian; Mehmed, Oral; Thorp, Scott A.

    1998-01-01

    The use of computational-model trained artificial neural networks to acquire damage specific information from electronic holograms is discussed. A neural network is trained to transform two time-average holograms into a pattern related to the bending-induced-strain distribution of the vibrating component. The bending distribution is very sensitive to component damage unlike the characteristic fringe pattern or the displacement amplitude distribution. The neural network processor is fast for real-time visualization of damage. The two-hologram limit makes the processor more robust to speckle pattern decorrelation. Undamaged and cracked cantilever plates serve as effective objects for testing the combination of electronic holography and neural-net processing. The requirements are discussed for using finite-element-model trained neural networks for field inspections of engine components. The paper specifically discusses neural-network fringe pattern analysis in the presence of the laser speckle effect and the performances of two limiting cases of the neural-net architecture.

  5. Characterizing mineral dusts and other aerosols from the Middle East--Part 1: ambient sampling.

    PubMed

    Engelbrecht, Johann P; McDonald, Eric V; Gillies, John A; Jayanty, R K M; Casuccio, Gary; Gertler, Alan W

    2009-02-01

    The purpose of the Enhanced Particulate Matter Surveillance Program was to provide scientifically founded information on the chemical and physical properties of dust collected over a period of approximately 1 year in Djibouti, Afghanistan (Bagram, Khowst), Qatar, United Arab Emirates, Iraq (Balad, Baghdad, Tallil, Tikrit, Taji, Al Asad), and Kuwait (northern, central, coastal, and southern regions). Three collocated low-volume particulate samplers, one each for the total suspended particulate matter, < 10 micro m in aerodynamic diameter (PM(10)) particulate matter, and < 2.5 micro m in aerodynamic diameter (PM(2.5)) particulate matter, were deployed at each of the 15 sites, operating on a '1 in 6' day sampling schedule. Trace-element analysis was performed to measure levels of potentially harmful metals, while major-element and ion-chemistry analyses provided an estimate of mineral components. Scanning electron microscopy with energy dispersive spectroscopy was used to analyze the chemical composition of small individual particles. Secondary electron images provided information on particle size and shape. This study shows the three main air pollutant types to be geological dust, smoke from burn pits, and heavy metal condensates (possibly from metals smelting and battery manufacturing facilities). Non-dust storm events resulted in elevated trace metal concentrations in Baghdad, Balad, and Taji in Iraq. Scanning-electron-microscopy secondary electron images of individual particles revealed no evidence of freshly fractured quartz grains. In all instances, quartz grains had rounded edges and mineral grains were generally coated by clay minerals and iron oxides.

  6. Composition and method for removing photoresist materials from electronic components

    DOEpatents

    Davenhall, Leisa B [Santa Fe, NM; Rubin, James B [Los Alamos, NM; Taylor, Craig M. V. [Jemez Springs, NM

    2008-06-03

    Composition and method for removing photoresist materials from electronic components. The composition is a mixture of at least one dense phase fluid and at least one dense phase fluid modifier. The method includes exposing a substrate to at least one pulse of the composition in a supercritical state to remove photoresist materials from the substrate.

  7. Composition and method for removing photoresist materials from electronic components

    DOEpatents

    Davenhall, Leisa B.; Rubin, James B.; Taylor, Craig M.

    2005-01-25

    Composition and method for removing photoresist materials from electronic components. The composition is a mixture of at least one dense phase fluid and at least one dense phase fluid modifier. The method includes exposing a substrate to at least one pulse of the composition in a supercritical state to remove photoresist materials from the substrate.

  8. 77 FR 4059 - Certain Electronic Devices for Capturing and Transmitting Images, and Components Thereof; Receipt...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2012-01-26

    ... Images, and Components Thereof; Receipt of Complaint; Solicitation of Comments Relating to the Public... Devices for Capturing and Transmitting Images, and Components Thereof, DN 2869; the Commission is... importation of certain electronic devices for capturing and transmitting images, and components thereof. The...

  9. Iron oxyhydroxide mineralization on microbial extracellular polysaccharides

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Chan, Clara S.; Fakra, Sirine C.; Edwards, David C.

    2010-06-22

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

  10. Multi-component sorption of Pb(II), Cu(II) and Zn(II) onto low-cost mineral adsorbent.

    PubMed

    Prasad, Murari; Xu, Huan-yan; Saxena, Sona

    2008-06-15

    Multi-component sorption studies were carried out for attenuation of divalent heavy metal cations (Pb2+, Cu2+ and Zn2+) by a low-cost mineral adsorbent from the aqueous solution. Kinetic and equilibrium batch-type sorption experiments were conducted under variable conditions for multi-component using low-grade (<12%P2O5) phosphate rock. Percentage of multiple heavy metal species removal increases with decreasing initial metals concentration and particle size. The equilibrium data were well described to a lesser extent by Freundlich model but Langmuir model seemed to be more appropriate with the fixation capacity obtained at room temperature for Pb2+, Cu2+ and Zn2+ was 227.2, 769.2 and 666.6 micromol g(-1), respectively. Two simple kinetic models were tested to investigate the adsorption mechanism. Rate constants have been found nearly constant at all metal concentrations for first order. The comparison of adsorption capacity of low-grade phosphate rock decreases in multi-component system as compared to single component due to ionic interactions. X-ray powder diffraction (XRPD) technique was used to ascertain the formation of new metal phases followed by surface complexation. Used adsorbents have been converted into a value added product by utilizing innovative Zero-waste concept to solve the used adsorbents disposal problem and thus protecting the environment.

  11. Mineral resources of Novokuznetsk administrative district of Kemerovo region (metallic and non-metallic minerals)

    NASA Astrophysics Data System (ADS)

    Gutak, Ja M.

    2017-09-01

    The article summarizes data on metallic and non-metallic minerals of Novokuznetsk district of Kemerovo region. Consistently reviewed are iron deposits (Tersinskaya group of deposits), gold deposits (placer accumulations and vein gold deposits), mineral water deposits (Tersinskoe deposit), deposit of refractory clay (Barkinskoe) and wide spread mineral deposits such as brick clay, keramzite materials, sand and gravel, building stones, ornamental stones, facing stones, peat, materials for lime production. It is indicated that resource base of metallic and nonmetallic minerals is inferior to that of mineral coal. At the same time it can be of considerable interest to small and medium-size businesses as objects with quick return of investment (facing and ornamental stones). For a number of wide spread mineral resources (brick clay, keramzite materials, sand and gravel) it is an important component of local industry.

  12. Imaging Cytoskeleton Components by Electron Microscopy.

    PubMed

    Svitkina, Tatyana

    2016-01-01

    The cytoskeleton is a complex of detergent-insoluble components of the cytoplasm playing critical roles in cell motility, shape generation, and mechanical properties of a cell. Fibrillar polymers-actin filaments, microtubules, and intermediate filaments-are major constituents of the cytoskeleton, which constantly change their organization during cellular activities. The actin cytoskeleton is especially polymorphic, as actin filaments can form multiple higher order assemblies performing different functions. Structural information about cytoskeleton organization is critical for understanding its functions and mechanisms underlying various forms of cellular activity. Because of the nanometer-scale thickness of cytoskeletal fibers, electron microscopy (EM) is a key tool to determine the structure of the cytoskeleton. This article describes application of rotary shadowing (or metal replica) EM for visualization of the cytoskeleton. The procedure is applicable to thin cultured cells growing on glass coverslips and consists of detergent extraction of cells to expose their cytoskeleton, chemical fixation to provide stability, ethanol dehydration and critical point drying to preserve three-dimensionality, rotary shadowing with platinum to create contrast, and carbon coating to stabilize replicas. This technique provides easily interpretable three-dimensional images, in which individual cytoskeletal fibers are clearly resolved, and individual proteins can be identified by immunogold labeling. More importantly, replica EM is easily compatible with live cell imaging, so that one can correlate the dynamics of a cell or its components, e.g., expressed fluorescent proteins, with high resolution structural organization of the cytoskeleton in the same cell.

  13. 77 FR 68829 - Certain Electronic Digital Media Devices and Components Thereof; Notice of Request for Statements...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2012-11-16

    ... INTERNATIONAL TRADE COMMISSION [Investigation No. 337-TA-796] Certain Electronic Digital Media... electronic digital media devices and components thereof imported by respondents Samsung Electronics Co, Ltd... Samsung. FOR FURTHER INFORMATION CONTACT: Cathy Chen, Office of the General Counsel, U.S. International...

  14. Recommendations for Enabling Manual Component Level Electronic Repair for Future Space Missions

    NASA Technical Reports Server (NTRS)

    Struk, Peter M.; Easton, John W.; Funk, Gregory P.; Latta, Gary S.; Ganster, Andrew W.; Estes, Brett E.

    2011-01-01

    Long duration missions to the Moon and Mars pose a number of challenges to mission designers, controllers, and the crews. Among these challenges are planning for corrective maintenance actions which often require a repair. Current repair strategies on the International Space Station (ISS) rely primarily on the use of Orbital Replacement Units (ORUs), where a faulty unit is replaced with a spare, and the faulty unit typically returns to Earth for analysis and possible repair. The strategy of replace to repair has posed challenges even for the ISS program. Repairing faulty hardware at lower levels such as the component level can help maintain system availability in situations where no spares exist and potentially reduce logistic resupply mass.This report provides recommendations to help enable manual replacement of electronics at the component-level for future manned space missions. The recommendations include hardware, tools, containment options, and crew training. The recommendations are based on the work of the Component Level Electronics Assembly Repair (CLEAR) task of the Exploration Technology Development Program from 2006 to 2009. The recommendations are derived based on the experience of two experiments conducted by the CLEAR team aboard the International Space Station as well as a group of experienced Miniature/Microminiature (2M) electronics repair technicians and instructors from the U.S. Navy 2M Project Office. The emphasis of the recommendations is the physical repair. Fault diagnostics and post-repair functional test are discussed in other CLEAR reports.

  15. Redox linked flavin sites in extracellular decaheme proteins involved in microbe-mineral electron transfer.

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Edwards, Marcus J.; White, Gaye F.; Norman, Michael

    2015-07-01

    Extracellular microbe-mineral electron transfer is a major driving force for the oxidation of organic carbon in many subsurface environments. Extracellular multi-heme cytochromes of the Shewenella genus play a major role in this process but the mechanism of electron exchange at the interface between cytochrome and acceptor is widely debated. The 1.8 Å x-ray crystal structure of the decaheme MtrC revealed a highly conserved CX₈C disulfide that, when substituted for AX₈A, severely compromised the ability of S. oneidensis to grow under aerobic conditions. Reductive cleavage of the disulfide in the presence of flavin mononucleotide (FMN) resulted in the reversible formation ofmore » a stable flavocytochrome. Similar results were also observed with other decaheme cytochromes, OmcA, MtrF and UndA. The data suggest that these decaheme cytochromes can transition between highly reactive flavocytochromes or less reactive cytochromes, and that this transition is controlled by a redox active disulfide that responds to the presence of oxygen.« less

  16. Mineralization of Carbon Dioxide: Literature Review

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Romanov, V; Soong, Y; Carney, C

    2015-01-01

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

  17. Component-Level Electronic-Assembly Repair (CLEAR) Spacecraft Circuit Diagnostics by Analog and Complex Signature Analysis

    NASA Technical Reports Server (NTRS)

    Oeftering, Richard C.; Wade, Raymond P.; Izadnegahdar, Alain

    2011-01-01

    The Component-Level Electronic-Assembly Repair (CLEAR) project at the NASA Glenn Research Center is aimed at developing technologies that will enable space-flight crews to perform in situ component-level repair of electronics on Moon and Mars outposts, where there is no existing infrastructure for logistics spares. These technologies must provide effective repair capabilities yet meet the payload and operational constraints of space facilities. Effective repair depends on a diagnostic capability that is versatile but easy to use by crew members that have limited training in electronics. CLEAR studied two techniques that involve extensive precharacterization of "known good" circuits to produce graphical signatures that provide an easy-to-use comparison method to quickly identify faulty components. Analog Signature Analysis (ASA) allows relatively rapid diagnostics of complex electronics by technicians with limited experience. Because of frequency limits and the growing dependence on broadband technologies, ASA must be augmented with other capabilities. To meet this challenge while preserving ease of use, CLEAR proposed an alternative called Complex Signature Analysis (CSA). Tests of ASA and CSA were used to compare capabilities and to determine if the techniques provided an overlapping or complementary capability. The results showed that the methods are complementary.

  18. Effects of mineral dust on global atmospheric nitrate concentrations

    NASA Astrophysics Data System (ADS)

    Karydis, V. A.; Tsimpidi, A. P.; Pozzer, A.; Astitha, M.; Lelieveld, J.

    2016-02-01

    This study assesses the chemical composition and global aerosol load of the major inorganic aerosol components, focusing on mineral dust and aerosol nitrate. The mineral dust aerosol components (i.e., Ca2+, Mg2+, K+, Na+) and their emissions are included in the ECHAM5/MESSy Atmospheric Chemistry model (EMAC). Gas/aerosol partitioning is simulated using the ISORROPIA-II thermodynamic equilibrium model that considers K+, Ca2+, Mg2+, NH4+, Na+, SO42-, NO3-, Cl-, and H2O aerosol components. Emissions of mineral dust are calculated online by taking into account the soil particle size distribution and chemical composition of different deserts worldwide. Presence of metallic ions can substantially affect the nitrate partitioning into the aerosol phase due to thermodynamic interactions. The model simulates highest fine aerosol nitrate concentration over urban and industrialized areas (1-3 µg m-3), while coarse aerosol nitrate is highest close to deserts (1-4 µg m-3). The influence of mineral dust on nitrate formation extends across southern Europe, western USA, and northeastern China. The tropospheric burden of aerosol nitrate increases by 44 % when considering interactions of nitrate with mineral dust. The calculated global average nitrate aerosol concentration near the surface increases by 36 %, while the coarse- and fine-mode concentrations of nitrate increase by 53 and 21 %, respectively. Other inorganic aerosol components are affected by reactive dust components as well (e.g., the tropospheric burden of chloride increases by 9 %, ammonium decreases by 41 %, and sulfate increases by 7 %). Sensitivity tests show that nitrate aerosol is most sensitive to the chemical composition of the emitted mineral dust, followed by the soil size distribution of dust particles, the magnitude of the mineral dust emissions, and the aerosol state assumption.

  19. 21 CFR 177.2355 - Mineral reinforced nylon resins.

    Code of Federal Regulations, 2012 CFR

    2012-04-01

    ... 21 Food and Drugs 3 2012-04-01 2012-04-01 false Mineral reinforced nylon resins. 177.2355 Section... as Components of Articles Intended for Repeated Use § 177.2355 Mineral reinforced nylon resins. Mineral reinforced nylon resins identified in paragraph (a) of this section may be safely used as articles...

  20. 21 CFR 177.2355 - Mineral reinforced nylon resins.

    Code of Federal Regulations, 2013 CFR

    2013-04-01

    ... 21 Food and Drugs 3 2013-04-01 2013-04-01 false Mineral reinforced nylon resins. 177.2355 Section... as Components of Articles Intended for Repeated Use § 177.2355 Mineral reinforced nylon resins. Mineral reinforced nylon resins identified in paragraph (a) of this section may be safely used as articles...

  1. 21 CFR 177.2355 - Mineral reinforced nylon resins.

    Code of Federal Regulations, 2011 CFR

    2011-04-01

    ... 21 Food and Drugs 3 2011-04-01 2011-04-01 false Mineral reinforced nylon resins. 177.2355 Section... as Components of Articles Intended for Repeated Use § 177.2355 Mineral reinforced nylon resins. Mineral reinforced nylon resins identified in paragraph (a) of this section may be safely used as articles...

  2. Solder Reflow Failures in Electronic Components During Manual Soldering

    NASA Technical Reports Server (NTRS)

    Teverovsky, Alexander; Greenwell, Chris; Felt, Frederick

    2008-01-01

    This viewgraph presentation reviews the solder reflow failures in electronic components that occur during manual soldering. It discusses the specifics of manual-soldering-induced failures in plastic devices with internal solder joints. The failure analysis turned up that molten solder had squeezed up to the die surface along the die molding compound interface, and the dice were not protected with glassivation allowing solder to short gate and source to the drain contact. The failure analysis concluded that the parts failed due to overheating during manual soldering.

  3. Non-autoclaved aerated concrete with mineral additives

    NASA Astrophysics Data System (ADS)

    Il'ina, L. V.; Rakov, M. A.

    2016-01-01

    We investigated the effect of joint grinding of Portland cement clinker, silica and carbonate components and mineral additives to specific surface of 280 - 300 m2/kg on the properties (strength, average density and thermal conductivity) of non-autoclaved aerated concrete, and the porosity of the hardened cement paste produced from Portland cement clinker with mineral additives. The joint grinding of the Portland cement clinker with silica and carbonate components and mineral additives reduces the energy consumption of non-autoclaved aerated concrete production. The efficiency of mineral additives (diopside, wollastonite) is due to the closeness the composition, the type of chemical bonds, physical and chemical characteristics (specific enthalpy of formation, specific entropy) to anhydrous clinker minerals and their hydration products. Considering the influence of these additions on hydration of clinker minerals and formation of hardened cement paste structure, dispersed wollastonite and diopside should be used as mineral additives. The hardness and, consequently, the elastic modulus of diopside are higher than that of hardened cement paste. As a result, there is a redistribution of stresses in the hardened cement paste interporous partitions and hardening, both the partitions and aerated concrete on the whole. The mineral additives introduction allowed to obtain the non-autoclaved aerated concrete with average density 580 kg/m3, compressive strength of 3.3 MPa and thermal conductivity of 0.131 W/(m.°C).

  4. Engineering Design Handbook. Dielectric Embedding of Electrical or Electronic Components

    DTIC Science & Technology

    1979-04-06

    its excellent electrical properties are maintained at elevated temperatures. Even when the insulation is exposed to a direct flame, it burns to a...machine by one operator; these molds are generally equipped with insulated handles to prevent personal in- jury from burns . In electronic embedment...Excellent for large volume runs; tooling is minimal. Pres- ence of a shell or housing as- sures no exposed components, as can occur in casting. Some

  5. Use of an Electronic Tongue System and Fuzzy Logic to Analyze Water Samples

    NASA Astrophysics Data System (ADS)

    Braga, Guilherme S.; Paterno, Leonardo G.; Fonseca, Fernando J.

    2009-05-01

    An electronic tongue (ET) system incorporating 8 chemical sensors was used in combination with two pattern recognition tools, namely principal component analysis (PCA) and Fuzzy logic for discriminating/classification of water samples from different sources (tap, distilled and three brands of mineral water). The Fuzzy program exhibited a higher accuracy than the PCA and allowed the ET to classify correctly 4 in 5 types of water. Exception was made for one brand of mineral water which was sometimes misclassified as tap water. On the other hand, the PCA grouped water samples in three clusters, one with the distilled water; a second with tap water and one brand of mineral water, and the third with the other two other brands of mineral water. Samples in the second and third clusters could not be distinguished. Nevertheless, close grouping between repeated tests indicated that the ET system response is reproducible. The potential use of the Fuzzy logic as the data processing tool in combination with an electronic tongue system is discussed.

  6. 78 FR 12354 - Certain Wireless Consumer Electronics Devices and Components Thereof; Commission Determination...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2013-02-22

    ... INTERNATIONAL TRADE COMMISSION [Investigation No. 337-TA-853] Certain Wireless Consumer Electronics Devices and Components Thereof; Commission Determination Concerning an Initial Determination Granting a Motion To Amend Complaint and Notice of Investigation AGENCY: U.S. International Trade...

  7. [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

  8. A novel aerobic sulfate reduction process in landfill mineralized refuse.

    PubMed

    Liu, Weijia; Long, Yuyang; Fang, Yuan; Ying, Luyao; Shen, Dongsheng

    2018-05-08

    It is thought that mineralized refuse could be excavated from almost-full landfill sites to provide space for the increasing burden of municipal solid waste. When excavating, however, the H 2 S emissions from the mineralized waste need to be considered carefully. In an attempt to understand how H 2 S emissions might change during this excavation process, we carried out a series of tests, including exposing anaerobic mineralized refuse to oxygen, isolating and determining possible functional bacteria, and characterizing the electron donors and/or acceptors. The results showed that H 2 S would be released when landfill mineralized refuse was exposed to oxygen (O 2 ), and could reach concentrations of 6 mg m -3 , which was 3 times the concentrations of H 2 S released from anaerobic mineralized refuse. Sulfur-metabolized microorganisms accounted for only 0.5% of the microbial functional bacteria (MFB) derived from the mineralized refuse when exposed to O 2 for 60 days, and SRB were not present. The MFB maintained H 2 S production by aerobic sulfate reduction using SO 4 2- and S 2 O 3 2- as electron acceptors, and sulfate-reducing rates of 16% and 55%, respectively, were achieved. Lactate and S 2 O 3 2- were the preferred electron donor and acceptor, respectively. By enhancing the carbon source and electron transfer, MFB may undergo strong aerobic sulfate reduction even at low abundances of sulfur-metabolized microorganisms. Copyright © 2018 Elsevier B.V. All rights reserved.

  9. Preservation of protein globules and peptidoglycan in the mineralized cell wall of nitrate-reducing, iron(II)-oxidizing bacteria: a cryo-electron microscopy study.

    PubMed

    Miot, J; Maclellan, K; Benzerara, K; Boisset, N

    2011-11-01

    Iron-oxidizing bacteria are important actors of the geochemical cycle of iron in modern environments and may have played a key role all over Earth's history. However, in order to better assess that role on the modern and the past Earth, there is a need for better understanding the mechanisms of bacterial iron oxidation and for defining potential biosignatures to be looked for in the geologic record. In this study, we investigated experimentally and at the nanometre scale the mineralization of iron-oxidizing bacteria with a combination of synchrotron-based scanning transmission X-ray microscopy (STXM), scanning transmission electron microscopy (STEM) and cryo-transmission electron microscopy (cryo-TEM). We show that the use of cryo-TEM instead of conventional microscopy provides detailed information of the successive iron biomineralization stages in anaerobic nitrate-reducing iron-oxidizing bacteria. These results suggest the existence of preferential Fe-binding and Fe-oxidizing sites on the outer face of the plasma membrane leading to the nucleation and growth of Fe minerals within the periplasm of these cells that eventually become completely encrusted. In contrast, the septa of dividing cells remain nonmineralized. In addition, the use of cryo-TEM offers a detailed view of the exceptional preservation of protein globules and the peptidoglycan within the Fe-mineralized cell walls of these bacteria. These organic molecules and ultrastructural details might be protected from further degradation by entrapment in the mineral matrix down to the nanometre scale. This is discussed in the light of previous studies on the properties of Fe-organic interactions and more generally on the fossilization of mineral-organic assemblies. © 2011 Blackwell Publishing Ltd.

  10. Biomimetic Bone-like Hydroxyapatite by Mineralization on Supramolecular Porous Fiber Networks.

    PubMed

    Li, Bo; Kan, Lei; Zhang, Xinyue; Li, Jie; Li, Ruiting; Gui, Qinyuan; Qiu, Dengli; He, Fei; Ma, Ning; Wang, Yapei; Wei, Hao

    2017-08-29

    Hydroxyapatite (HA), the main inorganic component of bone tissue, is mineralized with collagen fibril scaffolds during bone formation. Inspired by the process, a self-assembled porous network architecture was designed and synthesized by using the 2-ureido-4[1H]-pyrimidone (UPy) modified glycerol molecule UPy-Gly, which was further utilized as a template for biomimetic mineralization. When incubated in simulated body fluid (SBF), the HA nucleus first formed in the holes of the template by the induction of hydroxyls on the surface, grew along the nanofibers, and fused with the template to fabricate hydroxyapatite composites (UPy-Gly/HA). Transmission electron microscopic observation demonstrates that the mineral clusters are accumulated by lamella-like nano hydroxyapatite and the elasticity modulus measured by atomic force microscopy is about 5.5 GPa, which is quite close to the natural cancellous bone tissue of human both in structure and in mechanical properties. The Cell Counting Kit 8 (CCK-8) assay of UPy-Gly and UPy-Gly/HA shows noncytotoxicity to mouse fibroblast L-929 cells. This bioinspired composite will be a promising material for potential use in bone tissue implantation and regeneration engineering.

  11. 76 FR 55944 - In the Matter of Certain Electronic Devices With Image Processing Systems, Components Thereof...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2011-09-09

    ... With Image Processing Systems, Components Thereof, and Associated Software; Notice of Commission... importation of certain electronic devices with image processing systems, components thereof, and associated... direct infringement is asserted and the accused article does not meet every limitation of the asserted...

  12. Microsupercapacitors as miniaturized energy-storage components for on-chip electronics

    NASA Astrophysics Data System (ADS)

    Kyeremateng, Nana Amponsah; Brousse, Thierry; Pech, David

    2017-01-01

    The push towards miniaturized electronics calls for the development of miniaturized energy-storage components that can enable sustained, autonomous operation of electronic devices for applications such as wearable gadgets and wireless sensor networks. Microsupercapacitors have been targeted as a viable route for this purpose, because, though storing less energy than microbatteries, they can be charged and discharged much more rapidly and have an almost unlimited lifetime. In this Review, we discuss the progress and the prospects of integrated miniaturized supercapacitors. In particular, we discuss their power performances and emphasize the need of a three-dimensional design to boost their energy-storage capacity. This is obtainable, for example, through self-supported nanostructured electrodes. We also critically evaluate the performance metrics currently used in the literature to characterize microsupercapacitors and offer general guidelines to benchmark performances towards prospective applications.

  13. Microsupercapacitors as miniaturized energy-storage components for on-chip electronics.

    PubMed

    Kyeremateng, Nana Amponsah; Brousse, Thierry; Pech, David

    2017-01-01

    The push towards miniaturized electronics calls for the development of miniaturized energy-storage components that can enable sustained, autonomous operation of electronic devices for applications such as wearable gadgets and wireless sensor networks. Microsupercapacitors have been targeted as a viable route for this purpose, because, though storing less energy than microbatteries, they can be charged and discharged much more rapidly and have an almost unlimited lifetime. In this Review, we discuss the progress and the prospects of integrated miniaturized supercapacitors. In particular, we discuss their power performances and emphasize the need of a three-dimensional design to boost their energy-storage capacity. This is obtainable, for example, through self-supported nanostructured electrodes. We also critically evaluate the performance metrics currently used in the literature to characterize microsupercapacitors and offer general guidelines to benchmark performances towards prospective applications.

  14. An overview of vertebrate mineralization with emphasis on collagen-mineral interaction

    NASA Technical Reports Server (NTRS)

    Landis, W. J.

    1999-01-01

    The nucleation, growth, and development of mineral crystals through their interaction principally with collagen in normal bone and calcifying tendon have been elaborated by applying a number of different techniques for analysis of the inorganic and organic constituents of these tissues. The methods have included conventional and high voltage electron microscopy, electron diffraction, microscopic tomography and 3D image reconstruction, and atomic force microscopy. This summary presents results of these studies that have now characterized the size, shape, and aspects of the chemical nature of the crystals as well as their orientation, alignment, location, and distribution with respect to collagen. These data have provided the means for understanding more completely the formation and strength of the collagen-mineral composite present in most vertebrate calcifying tissues and, from that information, a basis for the adaptation of such tissues under mechanical constraints. In the context of the latter point, other data are given showing effects on collagen in bone cell cultures subjected to the unloading parameters of spaceflight. Implications of these results may be particularly relevant to explaining loss of bone by humans and other vertebrate animals during missions in space, during situations of extended fracture healing, long-term bedrest, physical immobilization, and related conditions. In a broader sense, the data speak to the response of bone and mineralized vertebrate tissues to changes in gravitational loading and applied mechanical forces in general.

  15. Toxicity of electronic waste leachates to Daphnia magna: screening and toxicity identification evaluation of different products, components, and materials.

    PubMed

    Lithner, Delilah; Halling, Maja; Dave, Göran

    2012-05-01

    Electronic waste has become one of the fastest growing waste problems in the world. It contains both toxic metals and toxic organics. The aim of this study was to (1) investigate to what extent toxicants can leach from different electronic products, components, and materials into water and (2) identify which group of toxicants (metals or hydrophobic organics) that is causing toxicity. Components from five discarded electronic products (cell phone, computer, phone modem, keyboard, and computer mouse) were leached in deionised water for 3 days at 23°C in concentrations of 25 g/l for metal components, 50 g/l for mixed-material components, and 100 g/l for plastic components. The water phase was tested for acute toxicity to Daphnia magna. Eighteen of 68 leachates showed toxicity (with immobility of D. magna ≥ 50% after 48 h) and came from metal or mixed-material components. The 8 most toxic leachates, with 48 h EC(50)s ranging from 0.4 to 20 g/l, came from 2 circuit sheets (key board), integrated drive electronics (IDE) cable clips (computer), metal studs (computer), a circuit board (computer mouse), a cord (phone modem), mixed parts (cell phone), and a circuit board (key board). All 5 electronic products were represented among them. Toxicity identification evaluations (with C18 and CM resins filtrations and ethylenediaminetetraacetic acid addition) indicated that metals caused the toxicity in the majority of the most toxic leachates. Overall, this study has shown that electronic waste can leach toxic compounds also during short-term leaching with pure water.

  16. Electrochemical analyses of redox-active iron minerals: a review of nonmediated and mediated approaches.

    PubMed

    Sander, Michael; Hofstetter, Thomas B; Gorski, Christopher A

    2015-05-19

    Redox-active minerals are ubiquitous in the environment and are involved in numerous electron transfer reactions that significantly affect biogeochemical processes and cycles as well as pollutant dynamics. As a consequence, research in different scientific disciplines is devoted to elucidating the redox properties and reactivities of minerals. This review focuses on the characterization of mineral redox properties using electrochemical approaches from an applied (bio)geochemical and environmental analytical chemistry perspective. Establishing redox equilibria between the minerals and working electrodes is a major challenge in electrochemical measurements, which we discuss in an overview of traditional electrochemical techniques. These issues can be overcome with mediated electrochemical analyses in which dissolved redox mediators are used to increase the rate of electron transfer and to facilitate redox equilibration between working electrodes and minerals in both amperometric and potentiometric measurements. Using experimental data on an iron-bearing clay mineral, we illustrate how mediated electrochemical analyses can be employed to derive important thermodynamic and kinetic data on electron transfer to and from structural iron. We summarize anticipated methodological advancements that will further contribute to advance an improved understanding of electron transfer to and from minerals in environmentally relevant redox processes.

  17. 76 FR 12994 - In the Matter of Certain Digital Televisions and Components Thereof, and Certain Electronic...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2011-03-09

    ... INTERNATIONAL TRADE COMMISSION [Inv. No. 337-TA-764] In the Matter of Certain Digital Televisions and Components Thereof, and Certain Electronic Devices Having a Blu-Ray Disc Player and Components Thereof; Notice of Investigation AGENCY: U.S. International Trade Commission. ACTION: Institution of...

  18. Measurement of the intrinsic electron neutrino component in the T2K neutrino beam with the ND280 detector

    NASA Astrophysics Data System (ADS)

    Abe, K.; Adam, J.; Aihara, H.; Akiri, T.; Andreopoulos, C.; Aoki, S.; Ariga, A.; Ariga, T.; Assylbekov, S.; Autiero, D.; Barbi, M.; Barker, G. J.; Barr, G.; Bass, M.; Batkiewicz, M.; Bay, F.; Bentham, S. W.; Berardi, V.; Berger, B. E.; Berkman, S.; Bertram, I.; Bhadra, S.; Blaszczyk, F. d. M.; Blondel, A.; Bojechko, C.; Bordoni, S.; Boyd, S. B.; Brailsford, D.; Bravar, A.; Bronner, C.; Buchanan, N.; Calland, R. G.; Caravaca Rodríguez, J.; Cartwright, S. L.; Castillo, R.; Catanesi, M. G.; Cervera, A.; Cherdack, D.; Christodoulou, G.; Clifton, A.; Coleman, J.; Coleman, S. J.; Collazuol, G.; Connolly, K.; Cremonesi, L.; Dabrowska, A.; Danko, I.; Das, R.; Davis, S.; de Perio, P.; De Rosa, G.; Dealtry, T.; Dennis, S. R.; Densham, C.; Di Lodovico, F.; Di Luise, S.; Drapier, O.; Duboyski, T.; Duffy, K.; Dufour, F.; Dumarchez, J.; Dytman, S.; Dziewiecki, M.; Emery, S.; Ereditato, A.; Escudero, L.; Finch, A. J.; Floetotto, L.; Friend, M.; Fujii, Y.; Fukuda, Y.; Furmanski, A. P.; Galymov, V.; Giffin, S.; Giganti, C.; Gilje, K.; Goeldi, D.; Golan, T.; Gomez-Cadenas, J. J.; Gonin, M.; Grant, N.; Gudin, D.; Hadley, D. R.; Haesler, A.; Haigh, M. D.; Hamilton, P.; Hansen, D.; Hara, T.; Hartz, M.; Hasegawa, T.; Hastings, N. C.; Hayato, Y.; Hearty, C.; Helmer, R. L.; Hierholzer, M.; Hignight, J.; Hillairet, A.; Himmel, A.; Hiraki, T.; Hirota, S.; Holeczek, J.; Horikawa, S.; Huang, K.; Ichikawa, A. K.; Ieki, K.; Ieva, M.; Ikeda, M.; Imber, J.; Insler, J.; Irvine, T. J.; Ishida, T.; Ishii, T.; Ives, S. J.; Iwai, E.; Iyogi, K.; Izmaylov, A.; Jacob, A.; Jamieson, B.; Johnson, R. A.; Jo, J. H.; Jonsson, P.; Jung, C. K.; Kabirnezhad, M.; Kaboth, A. C.; Kajita, T.; Kakuno, H.; Kameda, J.; Kanazawa, Y.; Karlen, D.; Karpikov, I.; Kearns, E.; Khabibullin, M.; Khotjantsev, A.; Kielczewska, D.; Kikawa, T.; Kilinski, A.; Kim, J.; Kisiel, J.; Kitching, P.; Kobayashi, T.; Koch, L.; Kolaceke, A.; Konaka, A.; Kormos, L. L.; Korzenev, A.; Koseki, K.; Koshio, Y.; Kreslo, I.; Kropp, W.; Kubo, H.; Kudenko, Y.; Kumaratunga, S.; Kurjata, R.; Kutter, T.; Lagoda, J.; Laihem, K.; Lamont, I.; Larkin, E.; Laveder, M.; Lawe, M.; Lazos, M.; Lee, K. P.; Lindner, T.; Lister, C.; Litchfield, R. P.; Longhin, A.; Ludovici, L.; Macaire, M.; Magaletti, L.; Mahn, K.; Malek, M.; Manly, S.; Marino, A. D.; Marteau, J.; Martin, J. F.; Maruyama, T.; Marzec, J.; Mathie, E. L.; Matveev, V.; Mavrokoridis, K.; Mazzucato, E.; McCarthy, M.; McCauley, N.; McFarland, K. S.; McGrew, C.; Metelko, C.; Mezzetto, M.; Mijakowski, P.; Miller, C. A.; Minamino, A.; Mineev, O.; Mine, S.; Missert, A.; Miura, M.; Monfregola, L.; Moriyama, S.; Mueller, Th. A.; Murakami, A.; Murdoch, M.; Murphy, S.; Myslik, J.; Nagasaki, T.; Nakadaira, T.; Nakahata, M.; Nakai, T.; Nakamura, K.; Nakayama, S.; Nakaya, T.; Nakayoshi, K.; Naples, D.; Nielsen, C.; Nirkko, M.; Nishikawa, K.; Nishimura, Y.; O'Keeffe, H. M.; Ohta, R.; Okumura, K.; Okusawa, T.; Oryszczak, W.; Oser, S. M.; Owen, R. A.; Oyama, Y.; Palladino, V.; Palomino, J.; Paolone, V.; Payne, D.; Perevozchikov, O.; Perkin, J. D.; Petrov, Y.; Pickard, L.; Pinzon Guerra, E. S.; Pistillo, C.; Plonski, P.; Poplawska, E.; Popov, B.; Posiadala, M.; Poutissou, J.-M.; Poutissou, R.; Przewlocki, P.; Quilain, B.; Radicioni, E.; Ratoff, P. N.; Ravonel, M.; Rayner, M. A. M.; Redij, A.; Reeves, M.; Reinherz-Aronis, E.; Retiere, F.; Robert, A.; Rodrigues, P. A.; Rojas, P.; Rondio, E.; Roth, S.; Rubbia, A.; Ruterbories, D.; Sacco, R.; Sakashita, K.; Sánchez, F.; Sato, F.; Scantamburlo, E.; Scholberg, K.; Schoppmann, S.; Schwehr, J.; Scott, M.; Seiya, Y.; Sekiguchi, T.; Sekiya, H.; Sgalaberna, D.; Shiozawa, M.; Short, S.; Shustrov, Y.; Sinclair, P.; Smith, B.; Smith, R. J.; Smy, M.; Sobczyk, J. T.; Sobel, H.; Sorel, M.; Southwell, L.; Stamoulis, P.; Steinmann, J.; Still, B.; Suda, Y.; Suzuki, A.; Suzuki, K.; Suzuki, S. Y.; Suzuki, Y.; Szeglowski, T.; Tacik, R.; Tada, M.; Takahashi, S.; Takeda, A.; Takeuchi, Y.; Tanaka, H. K.; Tanaka, H. A.; Tanaka, M. M.; Terhorst, D.; Terri, R.; Thompson, L. F.; Thorley, A.; Tobayama, S.; Toki, W.; Tomura, T.; Totsuka, Y.; Touramanis, C.; Tsukamoto, T.; Tzanov, M.; Uchida, Y.; Ueno, K.; Vacheret, A.; Vagins, M.; Vasseur, G.; Wachala, T.; Waldron, A. V.; Walter, C. W.; Wark, D.; Wascko, M. O.; Weber, A.; Wendell, R.; Wilkes, R. J.; Wilking, M. J.; Wilkinson, C.; Williamson, Z.; Wilson, J. R.; Wilson, R. J.; Wongjirad, T.; Yamada, Y.; Yamamoto, K.; Yanagisawa, C.; Yen, S.; Yershov, N.; Yokoyama, M.; Yuan, T.; Yu, M.; Zalewska, A.; Zalipska, J.; Zambelli, L.; Zaremba, K.; Ziembicki, M.; Zimmerman, E. D.; Zito, M.; Żmuda, J.; T2K Collaboration

    2014-05-01

    The T2K experiment has reported the first observation of the appearance of electron neutrinos in a muon neutrino beam. The main and irreducible background to the appearance signal comes from the presence in the neutrino beam of a small intrinsic component of electron neutrinos originating from muon and kaon decays. In T2K, this component is expected to represent 1.2% of the total neutrino flux. A measurement of this component using the near detector (ND280), located 280 m from the target, is presented. The charged current interactions of electron neutrinos are selected by combining the particle identification capabilities of both the time projection chambers and electromagnetic calorimeters of ND280. The measured ratio between the observed electron neutrino beam component and the prediction is 1.01±0.10 providing a direct confirmation of the neutrino fluxes and neutrino cross section modeling used for T2K neutrino oscillation analyses. Electron neutrinos coming from muons and kaons decay are also separately measured, resulting in a ratio with respect to the prediction of 0.68±0.30 and 1.10±0.14, respectively.

  19. Mineral features of connective dental hard tissues in hypoplastic amelogenesis imperfecta.

    PubMed

    Kammoun, R; Behets, C; Mansour, L; Ghoul-Mazgar, S

    2018-04-01

    To explore the mineral features of dentin and cementum in hypoplastic Amelogenesis imperfecta AI teeth. Forty-four (44) teeth cleaned and free of caries were used: 20 control and 24 affected by hypoplastic amelogenesis imperfecta. Thirty-two teeth were studied by pQCT, cut in sections, and analyzed under microradiography, polarized light microscopy, and confocal Raman spectroscopy. Eight teeth were observed under scanning electron microscope. Four teeth were used for an X-ray diffraction. The mineral density data were analyzed statistically with the Mann-Whitney U test, using GraphPad InStat software. Both coronal dentin and radicular dentin were less mineralized in AI teeth when compared to control (respectively 6.2% and 6.8%; p < .001). Root dentinal walls were thin and irregular, while the cellular cementum layers were thick, reaching sometimes the cervical region of the tooth. Regular dentinal tubules and sclerotic dentin areas were noticed. Partially tubular or cellular dysplastic dentin and hyper-, normo-, or hypomineralized areas were noticed in the inter-radicular areas of hypoplastic AI teeth. The main mineral component was carbonate hydroxyapatite as explored by Raman spectroscopy and X-ray diffraction. Dentin and cementum in hypoplastic AI teeth are (i) hypomineralized, (ii) constituted of carbonate hydroxyapatite, and (iii) of non-homogenous structure. © 2017 John Wiley & Sons A/S. Published by John Wiley & Sons Ltd. All rights reserved.

  20. The nanosphere iron mineral(s) in Mars soil

    NASA Technical Reports Server (NTRS)

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

    1993-01-01

    A series of surface-modified clays containing nanophase (np) iron/oxyhydroxides of extremely small particle sizes, with total iron contents as high as found in Mars soil, were prepared by iron deposition on the clay surface from ferrous chloride solution. Comprehensive studies of the iron mineralogy in these 'Mars-soil analogs' were conducted using chemical extractions, solubility analyses, pH and redox, x ray and electron diffractometry, electron microscopic imaging specific surface area and particle size determinations, differential thermal analyses, magnetic properties characterization, spectral reflectance, and Viking biology simulation experiments. The clay matrix and the procedure used for synthesis produced nanophase iron oxides containing a certain proportion of divalent iron, which slowly converts to more stable, fully oxidized iron minerals. The noncrystalline nature of the iron compounds precipitated on the surface of the clay was verified by their complete extractability in oxalate. Lepidocrocite (gamma-FeOOH) was detected by selected area electron diffraction. It is formed from a double iron Fe(II)/Fe(III) hydroxyl mineral such as 'green rust', or ferrosic hydroxide. Magnetic measurements suggested that lepidocrocite converted to the more stable meaghemite (gamma-Fe203) by mild heat treatment and then to nanophase hematite (aplha-Fe203) by extensive heat treatment. Their chemical reactivity offers a plausible mechanism for the somewhat puzzling observations of the Viking biology experiments. Their unique chemical reactivities are attributed to the combined catalytic effects of the iron oxide/oxyhydroxide and silicate phase surfaces. The mode of formation of these (nanophase) iron oxides on Mars is still unknown.

  1. Survey of Biodegradation of Electronic Components and Associated Testing Using Decontamination Solution

    DTIC Science & Technology

    1991-08-01

    Development and Engineering Center, ATTN: SMCCR- SPS -T, Aberdeen Proving Ground, MD 21010-5423. However, the Defense Technical Information Center and the...and conducting electrical tests to determine materiel degradation. Organisms of Penicillium s were among the most aggressive biota and, in some cases...tested electronic components for fungal degradation using Aspergillus, Penicillium , Alternaria, Streptomyces, and Rhodotorula. Electrical parameter

  2. Nacre in Abalone Shell: Organic and Inorganic Components and their effects to the Formation and Mechanical Properties

    NASA Astrophysics Data System (ADS)

    Lopez, Maria Isabel

    Abalone nacre is a natural composite that exhibits exceptional mechanical properties due to its organization that extends to various levels of hierarchy. Most of the toughness has been attributed by nacre's third level of hierarchy which entitles a brick and mortar structure consisting of the CaCO3 tiles and organic interlayers. However, there are other important components that are vital to the structure and strength of red abalone nacre. The process of formation of red abalone (Haliotis rufescens) nacre following periods of growth interruption, taking into consideration important environmental factors (access to food and temperature) and to employ high-magnification characterization techniques (scanning electron microscopy and transmission electron microscopy) to better understand how the soft tissue (e.g. epithelium and organic membrane) influences the mechanism of growth. The structure-property relationship of red abalone (Haliotis rufescens) nacre, focusing in the individual constituents (isolated mineral and isolated organic component) and comparing that to the integrated structure. Mechanical tests such as, tensile tests, microscratch, and nanoindentation is performed on the isolated organic constituent and the isolated mineral of red abalone shell. Specimens are characterized by SEM to verify the toughening and deformation mechanisms. Results obtained from the isolated mineral validate the importance of the organic constituent as the mechanical properties decline greatly as the organic component is removed. This approach forms a general picture of the mechanical response of the organic interlayers and growth bands and their effect on the toughness of the abalone nacre. These results are significant to understand the important characteristics of abalone nacre, such as the structure and mechanical properties, and an attempt to aid in improving the latest attempts to produce novel nacre-inspired materials.

  3. 42 CFR 37.60 - Submitting required chest roentgenograms and miner identification documents.

    Code of Federal Regulations, 2012 CFR

    2012-10-01

    ... prescribed in this subpart, all the forms shall be submitted with his or her name and social security account... miner identification document containing the miner's name, address, social security number and place of... format specified by NIOSH either using portable electronic media, or a secure electronic file transfer...

  4. Electronic zero-point fluctuation forces inside circuit components

    PubMed Central

    Leonhardt, Ulf

    2018-01-01

    One of the most intriguing manifestations of quantum zero-point fluctuations are the van der Waals and Casimir forces, often associated with vacuum fluctuations of the electromagnetic field. We study generalized fluctuation potentials acting on internal degrees of freedom of components in electrical circuits. These electronic Casimir-like potentials are induced by the zero-point current fluctuations of any general conductive circuit. For realistic examples of an electromechanical capacitor and a superconducting qubit, our results reveal the possibility of tunable forces between the capacitor plates, or the level shifts of the qubit, respectively. Our analysis suggests an alternative route toward the exploration of Casimir-like fluctuation potentials, namely, by characterizing and measuring them as a function of parameters of the environment. These tunable potentials may be useful for future nanoelectromechanical and quantum technologies. PMID:29719863

  5. Exogenic and endogenic Europa minerals

    NASA Astrophysics Data System (ADS)

    Maynard-Casely, H. E.; Brand, H. E. A.; Wilson, S. A.

    2016-12-01

    The Galileo Near Infrared Mapping Spectrometer (NIMS) identified a significant `non-ice' component upon the surface of Jupiter's moon Europa. Current explanations invoke both endogenic and exogenic origins for this material. It has long been suggested that magnesium and sodium sulfate minerals could have leached from the rock below a putative ocean (endogenic) 1 and that sulfuric acid hydrate minerals could have been radiologically produced from ionised sulfur originally from Io's volcanoes (exogenic) 2. However, a more recent theory proposes that the `non-ice' component could be radiation damaged NaCl leached from Europa's speculative ocean 3. What if the minerals are actually from combination of both endogenic and exogenic sources? To investigate this possibility we have focused on discovering new minerals that might form in the combination of the latter two cases, that is a mixture of leached sulfates hydrates with radiologically produced sulfuric acid. To this end we have explored a number of solutions in the MgSO4-H2SO4-H2O and Na2SO4-H2SO4-H2O systems, between 80 and 280 K with synchrotron x-ray powder diffraction. We report a number of new materials formed in this these ternary systems. This suggests that it should be considered that the `non-ice' component of the Europa's surface could be a material derived from endogenic and exogenic components. 1 Kargel, J. S. Brine volcanism and the interior structures of asteroids and icy satellites. Icarus 94, 368-390 (1991). 2 Carlson, R. W., Anderson, M. S., Mehlman, R. & Johnson, R. E. Distribution of hydrate on Europa: Further evidence for sulfuric acid hydrate. Icarus 177, 461-471, doi:10.1016/j.icarus.2005.03.026 (2005). 3 Hand, K. P. & Carlson, R. W. Europa's surface color suggests an ocean rich with sodium chloride. Geophysical Research Letters, 2015GL063559, doi:10.1002/2015gl063559 (2015).

  6. A Model for the Ultrastructure of Bone Based on Electron Microscopy of Ion-Milled Sections

    PubMed Central

    McNally, Elizabeth A.; Schwarcz, Henry P.; Botton, Gianluigi A.; Arsenault, A. Larry

    2012-01-01

    The relationship between the mineral component of bone and associated collagen has been a matter of continued dispute. We use transmission electron microscopy (TEM) of cryogenically ion milled sections of fully-mineralized cortical bone to study the spatial and topological relationship between mineral and collagen. We observe that hydroxyapatite (HA) occurs largely as elongated plate-like structures which are external to and oriented parallel to the collagen fibrils. Dark field images suggest that the structures (“mineral structures”) are polycrystalline. They are approximately 5 nm thick, 70 nm wide and several hundred nm long. Using energy-dispersive X-ray analysis we show that approximately 70% of the HA occurs as mineral structures external to the fibrils. The remainder is found constrained to the gap zones. Comparative studies of other species suggest that this structural motif is ubiquitous in all vertebrates. PMID:22272230

  7. Earth mineral resource of the month: asbestos

    USGS Publications Warehouse

    Virta, Robert L.

    2010-01-01

    The article discusses the characteristics and feature of asbestos. According to the author, asbestos is a generic name for six needle-shaped minerals that possess high tensile strengths, flexibility, and resistance to chemical and thermal degradation. These minerals are actinolite, amosite, anthophyllite, chrysolite, crocilodite and tremolite. Asbestos is used for strengthening concrete pipe, plastic components, and gypsum plasters.

  8. Magnesium-rich minerals in sediment and suspended particulates of South Florida water bodies: implications for turbidity.

    PubMed

    Harris, W G; Fisher, M M; Cao, X; Osborne, T; Ellis, L

    2007-01-01

    Fine sediments in shallow water bodies such as Lake Okeechobee are prone to resuspension. Predominantly inorganic "mud" sediment that covers approximately 670 km2 of the lake has been recognized as a persistent source of turbidity. The objective of this study was to determine if mineral components of sediments in Lake Okeechobee and water conveyances of the northern Everglades also occur as suspended sediment and hence constitute a potential abiotic contributor to turbidity. Sediment samples were collected from nine stations within the lake and eight locations north of Water Conservation Area 2A in the Everglades. Water samples were also collected at selected locations. The silt and clay mineralogy of sediment and suspended particles was determined using X-ray diffraction, thermogravimetry, scanning-electron microscopy, energy-dispersive X-ray elemental microanalysis, and high-resolution transmission-electron microscopy. Clay fractions of the lake sediment contained the Mg silicate minerals sepiolite and palygorskite, along with smectite, dolomite, calcite, and kaolinite. Sediment silt fractions were dominated by carbonates and/or quartz, with smaller amounts of Ca phosphates and sepiolite. Mineralogy of the mud sediment was similar to that reported for geologic phosphate deposits. This suggests that the mud sediment might have accumulated by stream transport of minerals from these deposits. Suspended solids and mud-sediment mineralogy were similar, except that smectite was more abundant in suspended solids. Everglade samples also contained Mg-rich minerals. The small size, low density, and fibrous or platy nature of the prevalent mud sediment minerals make them an abiotic, hydrodynamically sensitive source of persistent turbidity in a shallow lake. Mitigation efforts focused exclusively on P-induced biogeochemical processes do not address the origin or effects of these minerals. Ecological management issues such as turbidity control, P retention, geologic P input

  9. Measurements of the effective atomic numbers of minerals using bremsstrahlung produced by low-energy electrons

    NASA Astrophysics Data System (ADS)

    Czarnecki, S.; Williams, S.

    2017-12-01

    The accuracy of a method for measuring the effective atomic numbers of minerals using bremsstrahlung intensities has been investigated. The method is independent of detector-efficiency and maximum accelerating voltage. In order to test the method, experiments were performed which involved low-energy electrons incident on thick malachite, pyrite, and galena targets. The resultant thick-target bremsstrahlung was compared to bremsstrahlung produced using a standard target, and experimental effective atomic numbers were calculated using data from a previous study (in which the Z-dependence of thick-target bremsstrahlung was studied). Comparisons of the results to theoretical values suggest that the method has potential for implementation in energy-dispersive X-ray spectroscopy systems.

  10. Hypermineralized whale rostrum as the exemplar for bone mineral

    PubMed Central

    Li, Zhen; Pasteris, Jill D.; Novack, Deborah

    2013-01-01

    Although bone is a nanocomposite of mineral and collagen, mineral has been the more elusive component to study. A standard for bone mineral clearly is needed. We hypothesized that the most natural, least-processed bone mineral could be retrieved from the most highly mineralized bone. We therefore studied the rostrum of the toothed whale Mesoplodon densirostris, which has the densest recognized bone. Essential to establishment of a standard for bone mineral is documentation that the proposed tissue is bone-like in all properties except for its remarkably high concentration of mineral. Transmitted-light microscopy of unstained sections of rostral material shows normal bone morphology in osteon geometry, lacunae concentration, and vasculature development. Stained sections reveal extremely low density of thin collagen fibers throughout most of the bone, but enrichment in and thicker collagen fibers around vascular holes and in a minority of osteons. FE-SEM shows the rostrum to consist mostly of dense mineral prisms. Most rostral areas have the same chemical-structural features, Raman spectroscopically dominated by strong bands at ~962 Δcm−1 and weak bands at ~2940 Δcm−1. Spectral features indicate that the rostrum is composed mainly of the calcium phosphate mineral apatite and has only about 4 wt.% organic content. The degree of carbonate substitution (~8.5 wt.% carbonate) in the apatite is in the upper range found in most types of bone. We conclude that, despite its enamel-like extraordinarily high degree of mineralization, the rostrum is in all other features bone-like. Its mineral component is the long-sought uncontaminated, unaltered exemplar of bone mineral. PMID:23586370

  11. Kingian Co-Evolution of the Water and Mineral/Rock Components for Earth and Mars: Implications for Planetary Habitability (Invited)

    NASA Astrophysics Data System (ADS)

    Baker, V. R.

    2013-12-01

    Planetary habitability may fluctuate episodically against a background provided by the co-evolution of a planet's mineral/rock (geosphere) components and its water (hydrosphere) in relation to its position in a circumstellar system. The water/rock (geosphere/hydrosphere) co-evolution can be inferred from the geological histories of the terrestrial planets of the solar system, particularly from the very extensive understanding of Earth and Mars. Habitability and water/rock co-evolution have components that are tychistic (i.e., driven by chance) and anancastic (i.e., dynamically driven largely by deterministic forces). They also have a final, end-directed (i.e., teleomatic) aspect that operates in accordance with natural laws. This is a larger perspective on the idea of planetary habitability than is generally associated with an astronomical approach, and it incorporates additional insights from a geological perspective on the issue. The geological histories of Mars and Earth are punctuated with critical, short-term epochs of extreme change, which for Earth are known to be associated with major disruptions of its biosphere. These catastrophic epochs can be described as a type of non-Darwinian evolution that was envisioned by the geologist Clarence King. In an 1877 paper King proposed that accelerated evolutionary change occurs during sudden environmental disruptions. Such Kingian disruptions in mineral/rock and water evolution mark the planetary histories of Mars and Earth, including the early formation and condensation of a steam atmosphere, an impacting cataclysm at about 3.9 to 4 Ga, episodes of concentrated volcanism and tectonism, and associated rapid changes in the linked atmosphere and hydrosphere. These disruptions are closely tied to migrations of water between different planetary reservoirs, the nature of planetary accretion, the origin of a physically coupled atmosphere and ocean, the prospects for initiating plate tectonics, and punctuated greenhouse

  12. Mineral essential elements for nutrition in different chocolate products.

    PubMed

    Cinquanta, Luciano; Di Cesare, Cinzia; Manoni, Remo; Piano, Angela; Roberti, Piero; Salvatori, Giancarlo

    2016-11-01

    In this work, the essential mineral nutritional elements in cocoa beans, in chocolates at different cocoa percentage (60,70,80 and 90%) and in milk chocolate are evaluated. Dark chocolates are confirmed as an excellent source of magnesium (252.2 mg/100 g) and iron (10.9 mg/100 g): in chocolate containing 90% cocoa, their content corresponds to, respectively, 67.0% and 80.3 of Nutrient Reference Values (NRV) in the European Union. The chocolate containing 90% cocoa is also a good source of zinc (3.5 mg/100 g), which is important for the immune system, and selenium (0.1 mg/100 g). Three main components suitable to explain the mineral concentrations are analyzed by factor analysis. The component 1 can be interpreted as the contribution from the cocoa beans, owing to the mineral characteristics of the soil in which they have grown; the component 2 is mainly due to the manipulation and transformation of the cocoa in chocolate, while the component 3 represents the milk powder.

  13. In vivo imaging of free radicals produced by multivitamin-mineral supplements.

    PubMed

    Rabovsky, Alexander B; Buettner, Garry R; Fink, Bruno

    2015-12-01

    Redox active minerals in dietary supplements can catalyze unwanted and potentially harmful oxidations. To determine if this occurs in vivo we employed electron paramagnetic (EPR) imaging. We used 1-hydroxy-3-carboxy-2,2,5,5-tetramethylpyrrolidine (CPH) as a reporter for one-electron oxidations, e.g . free radical-mediated oxidations; the one-electron oxidation product of CPH, 3-carboxy-2,2,5,5-tetramethyl-1-pyrrolidinyloxy (CP • ), is a nitroxide free radical that is relatively persistent in vivo and detectable by EPR. As model systems, we used research formulations of vitamin mineral supplements (RVM) that are typical of commercial products. In in vitro experiments, upon suspension of RVM in aqueous solution, we observed: (1) the uptake of oxygen in the solution, consistent with oxidation of the components in the RVM; (2) the ascorbate free radical, a real-time indicator of ongoing oxidations; and (3) when amino acid/oligosaccharide (AAOS; glycinate or aspartate with non-digestible oligofructose) served as the matrix in the RVM, the rate of oxidation was significantly slowed. In a murine model, EPR imaging showed that the ingestion of RVM along with CPH results in the one-electron oxidation of CPH by RVM in the digestive system. The resulting CP • distributes throughout the body. Inclusion of AAOS in the RVM formulation diminished the oxidation of CPH to CP • in vivo. These data demonstrate that typical formulations of multivitamin/multimineral dietary supplements can initiate the oxidation of bystander substances and that AAOS-complexes of essential redox active metals, e.g . copper and iron, have reduced ability to catalyze free radical formation and associated detrimental oxidations when a part of a multivitamin/multimineral formulation.

  14. Arsenic mineral dissolution and possible mobilization in mineral-microbe-groundwater environment.

    PubMed

    Islam, A B M R; Maity, Jyoti Prakash; Bundschuh, Jochen; Chen, Chien-Yen; Bhowmik, Bejon Kumar; Tazaki, Kazue

    2013-11-15

    Arsenic (As) is widely distributed in the nature as ores or minerals. It has been attracted much attention for the global public health issue, especially for groundwater As contamination. The aim of this study was to elucidate the characteristics of microbes in groundwater where As-minerals were dissolved. An ex situ experiment was conducted with 7 standard As-minerals in bacteria-free groundwater and stored in experimental vessels for 1 year without supplementary nutrients. The pH (6.7-8.4) and EhS.H.E. (24-548 mV) changed between initial (0 day) and final stages (365 days) of experiment. The dissolution of As was detected higher from arsenolite (4240 ± 8.69 mg/L) and native arsenic (4538 ± 9.02 mg/L), whereas moderately dissolved from orpiment (653 ± 3.56 mg/L) and realgar (319 ± 2.56 mg/L) in compare to arsenopyrite (85 ± 1.25mg/L) and tennantite (3 ± 0.06 mg/L). Optical microscopic, scanning electron microscopic observations and flurometric enumeration revealed the abundance of As-resistant bacillus, coccus and filamentous types of microorganisms on the surface of most of As-mineral. 4'-6-Diamidino-2-phenylindole (DAPI)-stained epifluorescence micrograph confirmed the presence of DNA and carboxyfluorescein diacetate (CFDA) staining method revealed the enzymatically active bacteria on the surface of As-minerals such as in realgar (As4S4). Therefore, the microbes enable to survive and mobilize the As in groundwater by dissolution/bioweathering of As-minerals. Copyright © 2012. Published by Elsevier B.V.

  15. Molecular Characterization of Bacterial Respiration on Minerals

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Blake, Robert C.

    2013-04-26

    The overall aim of this project was to contribute to our fundamental understanding of proteins and biological processes under extreme environmental conditions. We sought to define the biochemical and physiological mechanisms that underlie biodegradative and other cellular processes in normal, extreme, and engineered environments. Toward that end, we sought to understand the substrate oxidation pathways, the electron transport mechanisms, and the modes of energy conservation employed during respiration by bacteria on soluble iron and insoluble sulfide minerals. In accordance with these general aims, the specific aims were two-fold: To identify, separate, and characterize the extracellular biomolecules necessary for aerobic respirationmore » on iron under strongly acidic conditions; and to elucidate the molecular principles whereby these bacteria recognize and adhere to their insoluble mineral substrates under harsh environmental conditions. The results of these studies were described in a total of nineteen manuscripts. Highlights include the following: 1. The complete genome of Acidithiobacillus ferrooxidans ATCC 23270 (type strain) was sequenced in collaboration with the DOE Joint Genome Institute; 2. Genomic and mass spectrometry-based proteomic methods were used to evaluate gene expression and in situ microbial activity in a low-complexity natural acid mine drainage microbial biofilm community. This was the first effort to successfully analyze a natural community using these techniques; 3. Detailed functional and structural studies were conducted on rusticyanin, an acid-stable electron transfer protein purified from cell-free extracts of At. ferrooxidans. The three-dimensional structure of reduced rusticyanin was determined from a combination of homonuclear proton and heteronuclear 15N- and 13C-edited NMR spectra. Concomitantly, the three-dimensional structure of oxidized rusticyanin was determined by X-ray crystallography to a resolution of 1.9 A by

  16. Probing the rhizosphere to define mineral organic relationships

    NASA Astrophysics Data System (ADS)

    Schulz, M. S.; Dohnalkova, A.; Stonestrom, D. A.

    2016-12-01

    Soil organic matter (SOM) accumulation and stabilization over time is an important process as soils are a large carbon reservoir in which feedbacks under changing climates are unclear. The association of SOM with poorly crystalline or short-range-ordered secondary minerals has been shown to be important for carbon stabilization. Commonly used soil extraction techniques display correlations of SOM with secondary phases but do not show causation. The fate of root exudates in soils and processes controlling exudate associations with mineral phases are as yet structurally undefined. Sub-micron exploration of in-situ relations provides valuable information on SOM-mineral interactions. Soils of the Santa Cruz (California) marine terrace chronosequence are used to illustrate changes in deep (> 1 m) rhizosphere through time. Cracks and soil ped faces are sites of high root density and organic matter (biofilm or mucilage) deposition. We employ a variety of scanning electron microscopy (SEM) and scanning transmission electron microscopy (STEM) techniques for high resolution imaging and elemental analyses of deep rhizosphere and associated carbon mineral interactions. In these coastal prairie soils microscopy reveals secondary clay minerals associated with and possibly forming from organic-rich mucilage that occurs along the aforementioned rooting networks on fracture surfaces. We hypothesize that the production of secondary clays in the rhizosphere is an important mode of C incorporation into secondary minerals.

  17. Transmission Electron Microscopy of Cometary Residues from Micron-Sized Craters in the Stardust Al-Foils

    NASA Technical Reports Server (NTRS)

    Leroux, Hugues; Stroud, Rhonda M.; Dai, Zu Rong; Graham, Giles A.; Troadec, David; Bradley, John P.; Teslich, Nick; Borg, Janet; Kearsley, Anton T.; Horz, Friedrich

    2008-01-01

    We report Transmission Electron Microscopy (TEM) investigations of micro-craters that originated from hypervelocity impacts of comet 81P/Wild 2 dust particles on the aluminium foil of the Stardust collector. The craters were selected by Scanning Electron Microscopy (SEM) and then prepared by Focused Ion Beam (FIB) milling techniques in order to provide electron transparent cross-sections for TEM studies. The crater residues contain both amorphous and crystalline materials in varying proportions and compositions. The amorphous component is interpreted as resulting from shock melting during the impact and the crystalline phases as relict minerals. The latter show evidence for shock metamorphism. Based on the residue morphology and the compositional variation, the impacting particles are inferred to have been dominated by mixtures of submicron olivine, pyroxene and Fe-sulfide grains, in agreement with prior results of relatively coarse-grained mineral assemblages in the aerogel collector.

  18. Emergency Dosimetry Using Ceramic Components in Personal Electronic Devices

    NASA Astrophysics Data System (ADS)

    Kouroukla, E. C.; Bailiff, I. K.; Terry, I.

    2014-02-01

    The rapid assessment of radiation dose to members of the public exposed to significant levels of ionizing radiation during a radiological incident presents a significant difficulty in the absence of planned radiation monitoring. However, within most personal electronic devices components such as resistors with alumina substrates can be found that have potentially suitable properties as solid state dosimeters using luminescence measurement techniques. The suitability of several types of ceramic-based components (e.g., resonators, inductors and resistors) has been previously examined using optically stimulated luminescence (OSL) and thermoluminescence (TL) techniques to establish their basic characteristics for the retrospective determination of absorbed dose. In this paper, we present results obtained with aluminum oxide surface mount resistors extracted from mobile phones that further extend this work. Very encouraging results have been obtained related to the measurement of luminescence sensitivity, dose response, reusability, limit of detection, signal reproducibility and known-dose recovery. However, the alumina exhibits a rapid loss of the latent luminescence signal with time following irradiation attributed to athermal (or anomalous) fading. The issues related to obtaining a reliable correction protocol for this loss and the detailed examinations required of the fading behavior are discussed.

  19. Skeletal biology: Where matrix meets mineral

    PubMed Central

    Young, Marian F.

    2017-01-01

    The skeleton is unique from all other tissues in the body because of its ability to mineralize. The incorporation of mineral into bones and teeth is essential to give them strength and structure for body support and function. For years, researchers have wondered how mineralized tissues form and repair. A major focus in this context has been on the role of the extracellular matrix, which harbors key regulators of the mineralization process. In this introductory minireview, we will review some key concepts of matrix biology as it related to mineralized tissues. Concurrently, we will highlight the subject of this special issue covering many aspects of mineralized tissues, including bones and teeth and their associated structures cartilage and tendon. Areas of emphasis are on the generation and analysis of new animal models with permutations of matrix components as well as the development of new approaches for tissue engineering for repair of damaged hard tissue. In assembling key topics on mineralized tissues written by leaders in our field, we hope the reader will get a broad view of the topic and all of its fascinating complexities. PMID:27131884

  20. Microbe-Clay Mineral Reactions and Characterization Techniques

    NASA Astrophysics Data System (ADS)

    Dong, H.; Zhang, G.; Ji, S.; Jaisi, D.; Kim, J.

    2008-12-01

    Clays and clay minerals are ubiquitous in soils, sediments, and sedimentary rocks. They play an important role in environmental processes such as nutrient cycling, plant growth, contaminant migration, organic matter maturation, and petroleum production. The changes in the oxidation state of the structural iron in clay minerals, in part, control their physical and chemical properties in natural environments, such as clay particle flocculation, dispersion, swelling, hydraulic conductivity, surface area, cation and anion exchange capacity, and reactivity towards organic and inorganic contaminants. The structural ferric iron [Fe(III)] in clay minerals can be reduced either chemically or biologically. Many different chemical reductants have been tried, but the most commonly used agent is dithionite. Biological reductants are bacteria, including dissimilatory iron reducing prokaryotes (DIRP) and sulfate-reducing bacteria (SRB). A wide variety of DIRP have been used to reduce ferric iron in clay minerals, including mesophilic, thermophilic, and hyperthermophilic prokaryotes. Multiple clay minerals have been used for microbial reduction studies, including smectite, nontronite (iron-rich smectite variety), illite, illite/smectite, chlorite, and their various mixtures. All these clay minerals are reducible by microorganisms under various conditions with smectite (nontronite) being the most reducible. The reduction extent and rate of ferric iron in clay minerals are measured by wet chemistry, and the reduced clay mineral products are typically characterized with chemical methods, X-ray diffraction, scanning and transmission electron microscopy, Mössbauer spectroscopy, Fourier Transform Infrared Spectroscopy (FTIR), UV-vis spectroscopy, and synchrotron-based techniques (such as EXAFS). Microbially reduced smectites (nontronites) have been found to be reactive in reducing a variety of organic and inorganic contaminants. Degradable organic contaminants include pesticides

  1. Glycine Polymerization on Oxide Minerals.

    PubMed

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

    2017-06-01

    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 NH 3 + group of adsorbed Gly to the nucleophilic NH 2 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.

  2. Optical properties of selected components of mineral dust aerosol processed with organic acids and humic material

    NASA Astrophysics Data System (ADS)

    Alexander, Jennifer M.; Grassian, V. H.; Young, M. A.; Kleiber, P. D.

    2015-03-01

    Visible light scattering phase function and linear polarization profiles of mineral dust components processed with organic acids and humic material are measured, and results are compared to T-matrix simulations of the scattering properties. Processed samples include quartz mixed with humic material, and calcite reacted with acetic and oxalic acids. Clear differences in light scattering properties are observed for all three processed samples when compared to the unprocessed dust or organic salt products. Results for quartz processed with humic acid sodium salt (NaHA) indicate the presence of both internally mixed quartz-NaHA particles and externally mixed NaHA aerosol. Simulations of light scattering suggest that the processed quartz particles become more moderate in shape due to the formation of a coating of humic material over the mineral core. Experimental results for calcite reacted with acetic acid are consistent with an external mixture of calcite and the reaction product, calcium acetate. Modeling of the light scattering properties does not require any significant change to the calcite particle shape distribution although morphology changes cannot be ruled out by our data. It is expected that calcite reacted with oxalic acid will produce internally mixed particles of calcite and calcium oxalate due to the low solubility of the product salt. However, simulations of the scattering for the calcite-oxalic acid system result in rather poor fits to the data when compared to the other samples. The poor fit provides a less accurate picture of the impact of processing in the calcite-oxalic acid system.

  3. Atomtronics: Realizing the behavior of electronic components in ultracold atomic systems

    NASA Astrophysics Data System (ADS)

    Pepino, Ron

    2007-06-01

    Atomtronics focuses on creating an analogy of electronic devices and circuits with ultracold atoms. Such an analogy can come from the highly tunable band structure of ultracold neutral atoms trapped in optical lattices. Solely by tuning the parameters of the optical lattice, we demonstrate that conditions can be created that cause atoms in lattices to exhibit the same behavior as electrons moving through solid state media. We present our model and show how the atomtronic diode, field effect transistor, and bipolar junction transistor can all be realized. Our analogs of these fundamental components exhibit precisely-controlled atomic signal amplification, trimming, and switching (on/off) characteristics. In addition, the evolution of dynamics of the superfluid atomic currents within these systems is completely reversible. This implies a possible use of atomtronic systems in the development of quantum computational devices.

  4. Fractionation of mineral species by electrophoresis

    NASA Technical Reports Server (NTRS)

    Dunning, J. D.; Herren, B. J.; Tipps, R. W.; Snyder, R. S.

    1982-01-01

    The fractionation of fine-grained aggregates into their major components is a problem in many scientific areas including earth and planetary science. Electrophoresis, the transport of electrically charged particles, immersed in a suspension medium, by a direct current field (Bier, 1959), was employed in this study as a means of separating simulated lunar soil into its constituent minerals. In these tests, conducted in a static analytical cylindrical microelectrophoresis apparatus, samples of simulated lunar soil and samples of pure mineral constituents were placed in the chamber; the electrophoretic mobilities of the lunar soil and the individual mineral constituents were measured. In most of the suspension buffers employed separability was indicated, on the basis of differences in mobility, for all the constituent mineral species except ilmenite and pyroxene, which were not efficiently separable in any of the buffers. Although only a few suspension media were employed, the success of this initial study suggests that electrophoresis may be an important mineral fractionation option in fine-grained aggregate processing.

  5. Management status of end-of-life vehicles and development strategies of used automotive electronic control components recycling industry in China.

    PubMed

    Wang, Junjun; Chen, Ming

    2012-11-01

    Recycling companies play a leading role in the system of end-of-life vehicles (ELVs) in China. Automotive manufacturers in China are rarely involved in recycling ELVs, and they seldom provide dismantling information for recycling companies. In addition, no professional shredding plant is available. The used automotive electronic control components recycling industry in China has yet to take shape because of the lack of supporting technology and profitable models. Given the rapid growth of the vehicle population and electronic control units in automotives in China, the used automotive electronic control components recycling industry requires immediate development. This paper analyses the current recycling system of ELVs in China and introduces the automotive product recycling technology roadmap as well as the recycling industry development goals. The strengths, weaknesses, opportunities and challenges of the current used automotive electronic control components recycling industry in China are analysed comprehensively based on the 'strengths, weaknesses, opportunities and threats' (SWOT) method. The results of the analysis indicate that this recycling industry responds well to all the factors and has good opportunities for development. Based on the analysis, new development strategies for the used automotive electronic control components recycling industry in accordance with the actual conditions of China are presented.

  6. Radiation and temperature effects on electronic components investigated under the CSTI high capacity power project

    NASA Technical Reports Server (NTRS)

    Schwarze, Gene E.; Niedra, Janis M.; Frasca, Albert J.; Wieserman, William R.

    1993-01-01

    The effects of nuclear radiation and high temperature environments must be fully known and understood for the electronic components and materials used in both the Power Conditioning and Control subsystem and the reactor Instrumentation and Control subsystem of future high capacity nuclear space power systems. This knowledge is required by the designer of these subsystems in order to develop highly reliable, long-life power systems for future NASA missions. A review and summary of the experimental results obtained for the electronic components and materials investigated under the power management element of the Civilian Space Technology Initiative (CSTI) high capacity power project are presented: (1) neutron, gamma ray, and temperature effects on power semiconductor switches, (2) temperature and frequency effects on soft magnetic materials; and (3) temperature effects on rare earth permanent magnets.

  7. Underground coal miners' foot and boot problems.

    PubMed

    Wood, G; Marr, S; Berry, G; Nubé, V; Cole, J

    1999-11-01

    The New South Wales (NSW) Joint Coal Board Health and Safety Trust funded an investigation into foot problems reported by 400 randomly selected underground coal miners from 15 mines in NSW. Miners were interviewed and their responses were entered directly into laptop computers. Digital cameras were also used to take pictures of skin conditions and miners' posture. Observations of the skin results indicate that miners find gumboots to be hot, sweaty and uncomfortable. Skin breakdown and tinea, is frequent and disabling and responsible for absences from the workforce that are costly for both miner and employer. A more comfortable and better designed boot is needed, fabricated in waterproof leather together with socks that 'wick' the moisture away from the foot. Socks worn were of varying components and washed at irregular intervals, indicating a need for regular changes of socks and improved hygiene.

  8. Effect of Mineral and Microbe Interactions on Biomass Yield

    NASA Astrophysics Data System (ADS)

    Pena, S. A.; Block, K. A.; Katz, A.; Gottlieb, P.

    2016-12-01

    The ecological feedback of microbes (bacteria and viruses) in association with minerals is virtually unexplored in the context of characterizing how carbon cycles in the terrestrial ecosystem. These interactions include the ability for bacteriophage to control bacteria populations, the ability of minerals to provide a substrate for bacteria growth, and the effect of minerals on bacteriophage viability. We investigate bacteriophage aggregation with minerals in the clay size fraction (< 0.2 µm) as well as the interaction between bacteriophage and mineral biofilms. In our virus experiments, bacteriophage Φ6 was suspended with the minerals smectite, illite, kaolinite, and goethite at low divalent cation concentrations so aggregation was in the reaction limited colloidal aggregation (RLCA) regime, at neutral pH and room temperature conditions. Virus remained viable at a 1:1 virus-clay ratio for clays, and at an approximate 100:1 ratio for goethite. However, the number of plaque forming units was reduced by 99%. Electron micrographs show viable as well as partially disassembled virus, similar to the results found by Block et al. 2014. We found that inactivation of a 4 x 1011 cm-3 concentration of bacteriophage Φ6 by smectite, illite, kaolinite, and goethite, required a minimum sediment concentration of 1.5 x 1011 cm-3, 1.4 x 1011 cm-3, 2.5 x 1011 cm-3, and 1.1 x 109 cm-3, respectively. Mineral biofilms were generated by suspension of tropical soil clays with gram-positive and gram-negative microbes and characterized by x-ray diffraction and imaged by electron microscopy (SEM and TEM). Mineral biomass produced by gram negative organisms were subjected to virus infection to determine influence of minerals on community resilience. Lastly, we report biomass yield in each instance to quantify the influence of mineral composition on total biomass production.

  9. In vivo imaging of free radicals produced by multivitamin-mineral supplements

    PubMed Central

    Buettner, Garry R.; Fink, Bruno

    2015-01-01

    Background Redox active minerals in dietary supplements can catalyze unwanted and potentially harmful oxidations. Methods To determine if this occurs in vivo we employed electron paramagnetic (EPR) imaging. We used 1-hydroxy-3-carboxy-2,2,5,5-tetramethylpyrrolidine (CPH) as a reporter for one-electron oxidations, e.g. free radical-mediated oxidations; the one-electron oxidation product of CPH, 3-carboxy-2,2,5,5-tetramethyl-1-pyrrolidinyloxy (CP•), is a nitroxide free radical that is relatively persistent in vivo and detectable by EPR. As model systems, we used research formulations of vitamin mineral supplements (RVM) that are typical of commercial products. Results In in vitro experiments, upon suspension of RVM in aqueous solution, we observed: (1) the uptake of oxygen in the solution, consistent with oxidation of the components in the RVM; (2) the ascorbate free radical, a real-time indicator of ongoing oxidations; and (3) when amino acid/oligosaccharide (AAOS; glycinate or aspartate with non-digestible oligofructose) served as the matrix in the RVM, the rate of oxidation was significantly slowed. In a murine model, EPR imaging showed that the ingestion of RVM along with CPH results in the one-electron oxidation of CPH by RVM in the digestive system. The resulting CP• distributes throughout the body. Inclusion of AAOS in the RVM formulation diminished the oxidation of CPH to CP• in vivo. Conclusions These data demonstrate that typical formulations of multivitamin/multimineral dietary supplements can initiate the oxidation of bystander substances and that AAOS-complexes of essential redox active metals, e.g. copper and iron, have reduced ability to catalyze free radical formation and associated detrimental oxidations when a part of a multivitamin/multimineral formulation. PMID:26705481

  10. Research on fault characteristics about switching component failures for distribution electronic power transformers

    NASA Astrophysics Data System (ADS)

    Sang, Z. X.; Huang, J. Q.; Yan, J.; Du, Z.; Xu, Q. S.; Lei, H.; Zhou, S. X.; Wang, S. C.

    2017-11-01

    The protection is an essential part for power device, especially for those in power grid, as the failure may cost great losses to the society. A study on the voltage and current abnormality in the power electronic devices in Distribution Electronic Power Transformer (D-EPT) during the failures on switching components is presented, as well as the operational principles for 10 kV rectifier, 10 kV/400 V DC-DC converter and 400 V inverter in D-EPT. Derived from the discussion on the effects of voltage and current distortion, the fault characteristics as well as a fault diagnosis method for D-EPT are introduced.

  11. Extracellular Electron Transfer and Survival Strategies in Acid Mine Drainage Impacted Soils

    NASA Astrophysics Data System (ADS)

    Gorby, Y. A.; Senko, J.

    2011-12-01

    Acid mine drainage (AMD) is a prominent and increasing problem in the greater Appalachian region of the United States and throughout the world. Recognition of the importance of extracellular electron transfer (EET) in microbial communities has provided a fertile research environment for multidisciplinary collaborations to emerge and effectively address complex questions with important environmental implications. Our research focuses on the components, strategies and mechanisms of EET in soil systems impacted by AMD and extends to other biogeochemical systems typified by steep redox gradients. Organisms within acid mine drainage use Fe(II) as their primary electron donor and couple Fe(II) oxidation to the reduction of oxygen as the terminal electron acceptor. Biogenic minerals formed by this process completely encase microbes in think deposits that would seem to limit diffusion of both Fe(II) and O2 for access by the organisms. We have developed methods for catalytically removing biogenic minerals revealing microorganisms and a fine network of filamentous extracellular material. Here we present a status report of our efforts to characterize the molecular and electronic properties of these filaments and to address the hypothesis that at least some of these filaments are electrically conductive microbial nanowires that facilitate electron transfer reactions within this complex biogeochemical system.

  12. Effect of Minerals on Intestinal IgA Production Using Deep Sea Water Drinks.

    PubMed

    Shiraishi, Hisashi; Fujino, Maho; Shirakawa, Naoki; Ishida, Nanao; Funato, Hiroki; Hirata, Ayumu; Abe, Noriaki; Iizuka, Michiro; Jobu, Kohei; Yokota, Junko; Miyamura, Mitsuhiko

    2017-01-01

    Minerals are essential for life, as they are a vital part of protein constituents, enzyme cofactors, and other components in living organisms. Deep sea water is characterized by its cleanliness and stable low temperature, and its possible health- and medical benefits are being studied. However, no study has yet evaluated the physical properties of the numerous commercially available deep sea water products, which have varying water sources and production methods. We analyzed these products' mineral content and investigated their effect on living organism, focusing on immune functions, and investigated the relation between physiological immunoactivities and mineral intake. We qualitatively analyzed the mineral compositions of the deep sea water drinks and evaluated the drinks' physical properties using principal component analysis, a type of multivariate analysis, of their mineral content. We create an iron and copper-deficient rat model and administered deep sea water drinks for 8 weeks. We then measured their fecal immunoglobulin A (IgA) to evaluate immune function. Principal component analysis suggested that physical properties of deep sea water drinks could be determined by their sources. Administration of deep sea water drinks increased fecal IgA, thus tending to stimulate immune function, but the extent of this effect varied by drink. Of the minerals contained in deep sea water, iron showed positive correlations with the fecal IgA. The principal component analysis used in this study is suitable for evaluating deep sea water containing many minerals, and our results form a useful basis for comparative evaluations of deep sea water's bioactivity.

  13. Amino Acid Contents of Meteorite Mineral Separates

    NASA Astrophysics Data System (ADS)

    Berger, E. L.; Burton, A. S.; Locke, D.

    2017-07-01

    We investigate the relationship between parent body conditions, mineralogy, and amino acid composition, by analyzing meteoric mineral separates using liquid chromatography-mass spectrometry, scanning electron microscopy, and x-ray diffraction.

  14. From chemolithoautotrophs to electrolithoautotrophs: CO2 fixation by Fe(II)-oxidizing bacteria coupled with direct uptake of electrons from solid electron sources.

    PubMed

    Ishii, Takumi; Kawaichi, Satoshi; Nakagawa, Hirotaka; Hashimoto, Kazuhito; Nakamura, Ryuhei

    2015-01-01

    At deep-sea vent systems, hydrothermal emissions rich in reductive chemicals replace solar energy as fuels to support microbial carbon assimilation. Until recently, all the microbial components at vent systems have been assumed to be fostered by the primary production of chemolithoautotrophs; however, both the laboratory and on-site studies demonstrated electrical current generation at vent systems and have suggested that a portion of microbial carbon assimilation is stimulated by the direct uptake of electrons from electrically conductive minerals. Here we show that chemolithoautotrophic Fe(II)-oxidizing bacterium, Acidithiobacillus ferrooxidans, switches the electron source for carbon assimilation from diffusible Fe(2+) ions to an electrode under the condition that electrical current is the only source of energy and electrons. Site-specific marking of a cytochrome aa3 complex (aa3 complex) and a cytochrome bc1 complex (bc1 complex) in viable cells demonstrated that the electrons taken directly from an electrode are used for O2 reduction via a down-hill pathway, which generates proton motive force that is used for pushing the electrons to NAD(+) through a bc1 complex. Activation of carbon dioxide fixation by a direct electron uptake was also confirmed by the clear potential dependency of cell growth. These results reveal a previously unknown bioenergetic versatility of Fe(II)-oxidizing bacteria to use solid electron sources and will help with understanding carbon assimilation of microbial components living in electronically conductive chimney habitats.

  15. From chemolithoautotrophs to electrolithoautotrophs: CO2 fixation by Fe(II)-oxidizing bacteria coupled with direct uptake of electrons from solid electron sources

    PubMed Central

    Ishii, Takumi; Kawaichi, Satoshi; Nakagawa, Hirotaka; Hashimoto, Kazuhito; Nakamura, Ryuhei

    2015-01-01

    At deep-sea vent systems, hydrothermal emissions rich in reductive chemicals replace solar energy as fuels to support microbial carbon assimilation. Until recently, all the microbial components at vent systems have been assumed to be fostered by the primary production of chemolithoautotrophs; however, both the laboratory and on-site studies demonstrated electrical current generation at vent systems and have suggested that a portion of microbial carbon assimilation is stimulated by the direct uptake of electrons from electrically conductive minerals. Here we show that chemolithoautotrophic Fe(II)-oxidizing bacterium, Acidithiobacillus ferrooxidans, switches the electron source for carbon assimilation from diffusible Fe2+ ions to an electrode under the condition that electrical current is the only source of energy and electrons. Site-specific marking of a cytochrome aa3 complex (aa3 complex) and a cytochrome bc1 complex (bc1 complex) in viable cells demonstrated that the electrons taken directly from an electrode are used for O2 reduction via a down-hill pathway, which generates proton motive force that is used for pushing the electrons to NAD+ through a bc1 complex. Activation of carbon dioxide fixation by a direct electron uptake was also confirmed by the clear potential dependency of cell growth. These results reveal a previously unknown bioenergetic versatility of Fe(II)-oxidizing bacteria to use solid electron sources and will help with understanding carbon assimilation of microbial components living in electronically conductive chimney habitats. PMID:26500609

  16. Supply of and demand for selected energy related mineral commodities

    USGS Publications Warehouse

    Sibley, Scott F.

    2010-01-01

    In this report, subjects discussed include components of mineral supply, production, and consumption data, and information on selected mineral commodities in which the Energy Critical Elements Study Group has an interest, and U.S. Geological Survey (USGS) recycling studies, with some results of these studies.

  17. 30 CFR 27.22 - Methane detector component.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... 30 Mineral Resources 1 2010-07-01 2010-07-01 false Methane detector component. 27.22 Section 27.22... APPROVAL OF MINING PRODUCTS METHANE-MONITORING SYSTEMS Construction and Design Requirements § 27.22 Methane detector component. (a) A methane detector component shall be suitably constructed for incorporation in or...

  18. 78 FR 63492 - Certain Electronic Devices, Including Mobile Phones and Tablet Computers, and Components Thereof...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2013-10-24

    ... INTERNATIONAL TRADE COMMISSION [Investigation No. 337-TA-847] Certain Electronic Devices, Including Mobile Phones and Tablet Computers, and Components Thereof; Notice of Request for Statements on the Public Interest AGENCY: U.S. International Trade Commission. ACTION: Notice. SUMMARY: Notice is...

  19. Quantum-mechanical predictions of electron-induced ionization cross sections of DNA components

    NASA Astrophysics Data System (ADS)

    Champion, Christophe

    2013-05-01

    Ionization of biomolecules remains still today rarely investigated on both the experimental and the theoretical sides. In this context, the present work appears as one of the first quantum mechanical approaches providing a multi-differential description of the electron-induced ionization process of the main DNA components for impact energies ranging from the target ionization threshold up to about 10 keV. The cross section calculations are here performed within the 1st Born approximation framework in which the ejected electron is described by a Coulomb wave whereas the incident and the scattered electrons are both described by a plane wave. The biological targets of interest, namely, the DNA nucleobases and the sugar-phosphate backbone, are here described by means of the GAUSSIAN 09 system using the restricted Hartree-Fock method with geometry optimization. The theoretical predictions also obtained have shown a reasonable agreement with the experimental total ionization cross sections while huge discrepancies have been pointed out with existing theoretical models, mainly developed within a semi-classical framework.

  20. Mineral content prediction for unconventional oil and gas reservoirs based on logging data

    NASA Astrophysics Data System (ADS)

    Maojin, Tan; Youlong, Zou; Guoyue

    2012-09-01

    Coal bed methane and shale oil &gas are both important unconventional oil and gas resources, whose reservoirs are typical non-linear with complex and various mineral components, and the logging data interpretation model are difficult to establish for calculate the mineral contents, and the empirical formula cannot be constructed due to various mineral. The radial basis function (RBF) network analysis is a new method developed in recent years; the technique can generate smooth continuous function of several variables to approximate the unknown forward model. Firstly, the basic principles of the RBF is discussed including net construct and base function, and the network training is given in detail the adjacent clustering algorithm specific process. Multi-mineral content for coal bed methane and shale oil &gas, using the RBF interpolation method to achieve a number of well logging data to predict the mineral component contents; then, for coal-bed methane reservoir parameters prediction, the RBF method is used to realized some mineral contents calculation such as ash, volatile matter, carbon content, which achieves a mapping from various logging data to multimineral. To shale gas reservoirs, the RBF method can be used to predict the clay content, quartz content, feldspar content, carbonate content and pyrite content. Various tests in coalbed and gas shale show the method is effective and applicable for mineral component contents prediction

  1. Application of Scanning Electron Microscopy/Energy-Dispersive X-Ray Spectroscopy for Characterization of Detrital Minerals in Karst Cave Speleothems.

    PubMed

    Zupančič, Nina; Miler, Miloš; Šebela, Stanka; Jarc, Simona

    2016-02-01

    Micro-scale observations in karst caves help to identify different processes that shaped local morphology. Scanning electron microscopy/energy-dispersive X-ray spectroscopy inspection of speleothems from two karst caves in Slovenia, Predjama and Črna Jama, confirmed the presence of sub-angular to sub-rounded detrital fragments of clay minerals, feldspars, quartz, Fe-oxides/hydroxides, rutile and Nb-rutile, xenotime, kassite, allanite, fluorapatite, epidote, ilmenite, monazite, sphene, and zircon, between 2 and 50 μm across. These occur in porous layers separating calcite laminae in the clayey coating on the layer below the surface of the speleothems, and are also incorporated within actual crystals. It is likely that they are derived from the weathered rocks of the Eocene flysch. Probably they were first transported into the caves by floodwaters forming cave sediments. Later, depending upon the climate conditions, they were moved by air currents or by water to the surface of active speleothems. They might also be redeposited from overlying soils enriched with wind-transported minerals from the flysch, or from higher passages filled with weathered flysch sediment, by drip water percolating through the fissured limestone. As some of the identified minerals are carriers of rare earth elements, Ti and Zr, their presence could affect any palaeoclimatic interpretations that are based upon the geochemical composition of the speleothems.

  2. Effect of Electrostatic Discharge on Electrical Characteristics of Discrete Electronic Components

    NASA Technical Reports Server (NTRS)

    Wysocki, Phil; Vashchenko, Vladislav; Celaya, Jose; Saha, Sankalita; Goebel, Kai

    2009-01-01

    This article reports on preliminary results of a study conducted to examine how temporary electrical overstress seed fault conditions in discrete power electronic components that cannot be detected with reliability tests but impact longevity of the device. These defects do not result in formal parametric failures per datasheet specifications, but result in substantial change in the electrical characteristics when compared with pristine device parameters. Tests were carried out on commercially available 600V IGBT devices using transmission line pulse (TLP) and system level ESD stress. It was hypothesized that the ESD causes local damage during the ESD discharge which may greatly accelerate degradation mechanisms and thus reduce the life of the components. This hypothesis was explored in simulation studies where different types of damage were imposed to different parts of the device. Experimental results agree qualitatively with the simulation for a number of tests which will motivate more in-depth modeling of the damage.

  3. Repair of dentin defects from DSPP knockout mice by PILP mineralization

    PubMed Central

    Nurrohman, H.; Saeki, K.; Carneiro, K.; Chien, Y.C.; Djomehri, S.; Ho, S.P.; Qin, C.; Marshall, S.J.; Gower, L.B.; Marshall, G.W.; Habelitz, S.

    2016-01-01

    Dentinogenesis imperfecta type II (DGI-II) lacks intrafibrillar mineral with severe compromise of dentin mechanical properties. A Dspp knockout (Dspp−/−) mouse, with a phenotype similar to that of human DGI-II, was used to determine if poly-L-aspartic acid [poly(ASP)] in the “polymer-induced liquid-precursor” (PILP) system can restore its mechanical properties. Dentin from six-week old Dspp−/− and wild-type mice was treated with CaP solution containing poly(ASP) for up to 14 days. Elastic modulus and hardness before and after treatment were correlated with mineralization from Micro x-ray computed tomography (Micro-XCT). Transmission electron microscopy (TEM)/Selected area electron diffraction (SAED) were used to compare matrix mineralization and crystallography. Mechanical properties of the Dspp−/− dentin were significantly less than wild-type dentin and recovered significantly (P < 0.05) after PILP-treatment, reaching values comparable to wild-type dentin. Micro-XCT showed mineral recovery similar to wild-type dentin after PILP-treatment. TEM/SAED showed repair of patchy mineralization and complete mineralization of defective dentin. This approach may lead to new strategies for hard tissue repair. PMID:27239097

  4. 30 CFR 7.507 - Air-monitoring components.

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... 30 Mineral Resources 1 2012-07-01 2012-07-01 false Air-monitoring components. 7.507 Section 7.507... APPROVAL OF MINING PRODUCTS TESTING BY APPLICANT OR THIRD PARTY Refuge Alternatives § 7.507 Air-monitoring components. (a) Each refuge alternative shall have an air-monitoring component that provides persons inside...

  5. 30 CFR 7.507 - Air-monitoring components.

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... 30 Mineral Resources 1 2013-07-01 2013-07-01 false Air-monitoring components. 7.507 Section 7.507... APPROVAL OF MINING PRODUCTS TESTING BY APPLICANT OR THIRD PARTY Refuge Alternatives § 7.507 Air-monitoring components. (a) Each refuge alternative shall have an air-monitoring component that provides persons inside...

  6. 30 CFR 7.507 - Air-monitoring components.

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... 30 Mineral Resources 1 2014-07-01 2014-07-01 false Air-monitoring components. 7.507 Section 7.507... APPROVAL OF MINING PRODUCTS TESTING BY APPLICANT OR THIRD PARTY Refuge Alternatives § 7.507 Air-monitoring components. (a) Each refuge alternative shall have an air-monitoring component that provides persons inside...

  7. Minerals in the foods eaten by mountain gorillas (Gorilla beringei).

    PubMed

    Cancelliere, Emma C; DeAngelis, Nicole; Nkurunungi, John Bosco; Raubenheimer, David; Rothman, Jessica M

    2014-01-01

    Minerals are critical to an individual's health and fitness, and yet little is known about mineral nutrition and requirements in free-ranging primates. We estimated the mineral content of foods consumed by mountain gorillas (Gorilla beringei beringei) in the Bwindi Impenetrable National Park, Uganda. Mountain gorillas acquire the majority of their minerals from herbaceous leaves, which constitute the bulk of their diet. However, less commonly eaten foods were sometimes found to be higher in specific minerals, suggesting their potential importance. A principal component analysis demonstrated little correlation among minerals in food items, which further suggests that mountain gorillas might increase dietary diversity to obtain a full complement of minerals in their diet. Future work is needed to examine the bioavailability of minerals to mountain gorillas in order to better understand their intake in relation to estimated needs and the consequences of suboptimal mineral balance in gorilla foods.

  8. Minerals in the Foods Eaten by Mountain Gorillas (Gorilla beringei)

    PubMed Central

    Cancelliere, Emma C.; DeAngelis, Nicole; Nkurunungi, John Bosco; Raubenheimer, David; Rothman, Jessica M.

    2014-01-01

    Minerals are critical to an individual’s health and fitness, and yet little is known about mineral nutrition and requirements in free-ranging primates. We estimated the mineral content of foods consumed by mountain gorillas (Gorilla beringei beringei) in the Bwindi Impenetrable National Park, Uganda. Mountain gorillas acquire the majority of their minerals from herbaceous leaves, which constitute the bulk of their diet. However, less commonly eaten foods were sometimes found to be higher in specific minerals, suggesting their potential importance. A principal component analysis demonstrated little correlation among minerals in food items, which further suggests that mountain gorillas might increase dietary diversity to obtain a full complement of minerals in their diet. Future work is needed to examine the bioavailability of minerals to mountain gorillas in order to better understand their intake in relation to estimated needs and the consequences of suboptimal mineral balance in gorilla foods. PMID:25372712

  9. Mineral deposition in bacteria-filled and bacteria-free calcium bodies in the crustacean Hyloniscus riparius (Isopoda: Oniscidea).

    PubMed

    Vittori, Miloš; Rozman, Alenka; Grdadolnik, Jože; Novak, Urban; Štrus, Jasna

    2013-01-01

    Crustacean calcium bodies are epithelial sacs which contain a mineralized matrix. The objectives of this study were to describe the microscopic anatomy of calcium bodies in the terrestrial isopod Hyloniscus riparius and to establish whether they undergo molt-related structural changes. We performed 3D reconstruction of the calcium bodies from paraffin sections and analyzed their structure with light and electron microscopy. In addition, we analyzed the chemical composition of their mineralized matrices with micro-Raman spectroscopy. Two pairs of these organs are present in H. riparius. One pair is filled with bacteria while the other pair is not. In non-molting animals, the bacteria-filled calcium bodies contain apatite crystals and the bacteria-free calcium bodies enclose CaCO3-containing concretions with little organic matrix. During preparation for molt, an additional matrix layer is deposited in both pairs of calcium bodies. In the bacteria-filled calcium bodies it contains a mixture of calcium carbonate and calcium phosphate, whereas only calcium carbonate is present in bacteria-free calcium bodies. After ecdysis, all mineral components in bacteria-free calcium bodies and the additional matrix layer in bacteria-filled calcium bodies are completely resorbed. During calcium resorption, the apical surface of the calcium body epithelium is deeply folded and electron dense granules are present in spaces between epithelial cells. Our results indicate that the presence of bacteria might be linked to calcium phosphate mineralization. Calcium bodies likely provide a source of calcium and potentially phosphate for the mineralization of the new cuticle after molt. Unlike other terrestrial isopods, H. riparius does not form sternal CaCO3 deposits and the bacteria-free calcium bodies might functionally replace them in this species.

  10. Mineral Deposition in Bacteria-Filled and Bacteria-Free Calcium Bodies in the Crustacean Hyloniscus riparius (Isopoda: Oniscidea)

    PubMed Central

    Vittori, Miloš; Rozman, Alenka; Grdadolnik, Jože; Novak, Urban; Štrus, Jasna

    2013-01-01

    Crustacean calcium bodies are epithelial sacs which contain a mineralized matrix. The objectives of this study were to describe the microscopic anatomy of calcium bodies in the terrestrial isopod Hyloniscus riparius and to establish whether they undergo molt-related structural changes. We performed 3D reconstruction of the calcium bodies from paraffin sections and analyzed their structure with light and electron microscopy. In addition, we analyzed the chemical composition of their mineralized matrices with micro-Raman spectroscopy. Two pairs of these organs are present in H. riparius. One pair is filled with bacteria while the other pair is not. In non-molting animals, the bacteria-filled calcium bodies contain apatite crystals and the bacteria-free calcium bodies enclose CaCO3-containing concretions with little organic matrix. During preparation for molt, an additional matrix layer is deposited in both pairs of calcium bodies. In the bacteria-filled calcium bodies it contains a mixture of calcium carbonate and calcium phosphate, whereas only calcium carbonate is present in bacteria-free calcium bodies. After ecdysis, all mineral components in bacteria-free calcium bodies and the additional matrix layer in bacteria-filled calcium bodies are completely resorbed. During calcium resorption, the apical surface of the calcium body epithelium is deeply folded and electron dense granules are present in spaces between epithelial cells. Our results indicate that the presence of bacteria might be linked to calcium phosphate mineralization. Calcium bodies likely provide a source of calcium and potentially phosphate for the mineralization of the new cuticle after molt. Unlike other terrestrial isopods, H. riparius does not form sternal CaCO3 deposits and the bacteria-free calcium bodies might functionally replace them in this species. PMID:23554963

  11. Microstructure-Evolution and Reliability Assessment Tool for Lead-Free Component Insertion in Army Electronics

    DTIC Science & Technology

    2008-10-01

    provide adequate means for thermal heat dissipation and cooling. Thus electronic packaging has four main functions [1]: • Signal distribution which... dissipation , involving structural and materials consideration. • Mechanical, chemical and electromagnetic protection of components and... nature when compared to phenomenological models. Microelectronic packaging industry spends typically several months building and reliability

  12. Microbial mineralization of cis-dichloroethene and vinyl chloride as a component of natural attenuation of chloroethene contaminants under conditions identified in the field as anoxic

    USGS Publications Warehouse

    Bradley, Paul M.

    2012-01-01

    Chlororespiration is a key component of remediation at many chloroethene-contaminated sites. In some instances, limited accumulation of reductive dechlorination daughter products may suggest that natural attenuation is not adequate for site remediation. This conclusion is justified when evidence for parent compound (tetrachloroethene, PCE, or trichloroethene, TCE) degradation is lacking. For many chloroethene-contaminated shallow aquifer systems, however, non-conservative losses of the parent compounds are clear but the mass balance between parent compound attenuation and accumulation of reductive dechlorination daughter products is incomplete. Incomplete mass balance indicates a failure to account for important contaminant attenuation mechanisms, and is consistent with contaminant degradation to non-diagnostic mineralization products. An ongoing technical debate over the potential for mineralization of dichloroethene (DCE) and vinyl chloride (VC) to CO2 in the complete absence of diatomic oxygen has largely obscured the importance of microbial DCE/VC mineralization at dissolved oxygen (DO) concentrations below the current field standard (DO < 0.1-0.5 milligrams per liter) for nominally anoxic conditions. This study demonstrates that oxygen-based microbial mineralization of DCE and VC can be substantial under field conditions that are frequently characterized as "anoxic." Because mischaracterization of operant contaminant biodegradation processes can lead to expensive and ineffective remedial actions, a modified framework for assessing the potential importance of oxygen during chloroethene biodegradation was developed.

  13. The application of artificial intelligence for the identification of the maceral groups and mineral components of coal

    NASA Astrophysics Data System (ADS)

    Mlynarczuk, Mariusz; Skiba, Marta

    2017-06-01

    The correct and consistent identification of the petrographic properties of coal is an important issue for researchers in the fields of mining and geology. As part of the study described in this paper, investigations concerning the application of artificial intelligence methods for the identification of the aforementioned characteristics were carried out. The methods in question were used to identify the maceral groups of coal, i.e. vitrinite, inertinite, and liptinite. Additionally, an attempt was made to identify some non-organic minerals. The analyses were performed using pattern recognition techniques (NN, kNN), as well as artificial neural network techniques (a multilayer perceptron - MLP). The classification process was carried out using microscopy images of polished sections of coals. A multidimensional feature space was defined, which made it possible to classify the discussed structures automatically, based on the methods of pattern recognition and algorithms of the artificial neural networks. Also, from the study we assessed the impact of the parameters for which the applied methods proved effective upon the final outcome of the classification procedure. The result of the analyses was a high percentage (over 97%) of correct classifications of maceral groups and mineral components. The paper discusses also an attempt to analyze particular macerals of the inertinite group. It was demonstrated that using artificial neural networks to this end makes it possible to classify the macerals properly in over 91% of cases. Thus, it was proved that artificial intelligence methods can be successfully applied for the identification of selected petrographic features of coal.

  14. Conductive iron oxide minerals accelerate syntrophic cooperation in methanogenic benzoate degradation.

    PubMed

    Zhuang, Li; Tang, Jia; Wang, Yueqiang; Hu, Min; Zhou, Shungui

    2015-08-15

    Recent studies have suggested that conductive iron oxide minerals can facilitate syntrophic metabolism of the methanogenic degradation of organic matter, such as ethanol, propionate and butyrate, in natural and engineered microbial ecosystems. This enhanced syntrophy involves direct interspecies electron transfer (DIET) powered by microorganisms exchanging metabolic electrons through electrically conductive minerals. Here, we evaluated the possibility that conductive iron oxides (hematite and magnetite) can stimulate the methanogenic degradation of benzoate, which is a common intermediate in the anaerobic metabolism of aromatic compounds. The results showed that 89-94% of the electrons released from benzoate oxidation were recovered in CH4 production, and acetate was identified as the only carbon-bearing intermediate during benzoate degradation. Compared with the iron-free controls, the rates of methanogenic benzoate degradation were enhanced by 25% and 53% in the presence of hematite and magnetite, respectively. This stimulatory effect probably resulted from DIET-mediated methanogenesis in which electrons transfer between syntrophic partners via conductive iron minerals. Phylogenetic analyses revealed that Bacillaceae, Peptococcaceae, and Methanobacterium are potentially involved in the functioning of syntrophic DIET. Considering the ubiquitous presence of iron minerals within soils and sediments, the findings of this study will increase the current understanding of the natural biological attenuation of aromatic hydrocarbons in anaerobic environments. Copyright © 2015 Elsevier B.V. All rights reserved.

  15. The Online Mineral Library at the University of Minnesota

    NASA Astrophysics Data System (ADS)

    Feinberg, J. M.; Burdette, E.; Clayton, M.

    2012-12-01

    The University of Minnesota maintains a world-class mineral collection comprising over 7000 specimens, many of which are museum quality. Prof. Newton H. Winchell started the collection in the 1850s shortly after the founding of the University itself. Many of the specimens come from pioneering mineralogists such as Winchell, George F. Kunz, and Tibor Zoltai. A small fraction of the most eye-catching samples are on public display within the Department of Earth Sciences, but until recently the vast majority of the collection was housed in locked metal cabinets, which meant that the collection received very little use by students and researchers. To improve the visibility and accessibility of our mineral collection we created an elegant, database-driven website (http://mineral.esci.umn.edu/). This dynamic website is one of the more extensive of its kind and allows the collection to be used as a tool for teaching and research. The searchable, online database contains high-resolution photographs of the University's mineral collection and provides access to the complete collection. Administrators can link numerous specimens to create online "collections" that emphasize particular themes, e.g., economic mineralogy, common mineral donors, or common geographic origin. The online database has already been interwoven into courses for Earth Science majors and non-majors. Researchers are able to explore the library for mineral standards for instrument calibration or more involved experimental research. Further, the online library allows graduate students and faculty to "check out" certain mineral specimens for research, which for the first time allows us to accurately track the use of the collection. The electronic framework for the Online Mineral Library was constructed using the Drupal open source content management system. Undergraduate interns are in the process of systematically photographing each of the mineral specimens for inclusion in the Online Library. Additionally

  16. Exploring the Relationships between the Electronic Health Record System Components and Patient Outcomes in an Acute Hospital Setting

    ERIC Educational Resources Information Center

    Wiggley, Shirley L.

    2011-01-01

    Purpose: The purpose of this study was to examine the relationship between the electronic health record system components and patient outcomes in an acute hospital setting, given that the current presidential administration has earmarked nearly $50 billion to the implementation of the electronic health record. The relationship between the…

  17. Enamel mineral loss.

    PubMed

    West, Nicola X; Joiner, Andrew

    2014-06-01

    To summarise the chemical, biological and host factors that impact enamel mineral loss, to highlight approaches to contemporary management of clinical conditions involving mineral loss and summarise emerging trends and challenges in this area. "Medline" and "Scopus" databases were searched electronically with the principal key words tooth, enamel, *mineral*, caries and erosion. Language was restricted to English and original studies and reviews were included. Conference papers and abstracts were excluded. Enamel mineral loss leads to the degradation of the surface and subsurface structures of teeth. This can impact their shape, function, sensitivity and aesthetic qualities. Dental caries is a multifactorial disease caused by the simultaneous interplay of dietary sugars, dental plaque, the host and time. There is a steady decline in dental caries in developed countries and the clinical management of caries is moving towards a less invasive intervention, with risk assessment, prevention, control, restoration and recall. Tooth wear can be caused by erosion, abrasion and attrition. Dental erosion can be the result of acid from intrinsic sources, such as gastric acids, or extrinsic sources, in particular from the diet and consumption of acidic foods and drinks. Its prevalence is increasing and it increases with age. Clinical management requires diagnosis and risk assessment to understand the underlying aetiology, so that optimal preventative measures can be implemented. Overall, prevention of enamel mineral loss from caries and tooth wear should form the basis of lifelong dental management. Evidence based oral hygiene and dietary advice is imperative, alongside preventive therapy, to have a healthy lifestyle, whilst retaining hard tooth tissue. © 2014 Elsevier Ltd. All rights reserved.

  18. Proteins and saccharides of the sea urchin organic matrix of mineralization: characterization and localization in the spine skeleton.

    PubMed

    Ameye, L; De Becker, G; Killian, C; Wilt, F; Kemps, R; Kuypers, S; Dubois, P

    2001-04-01

    Properties of the echinoderm skeleton are under biological control, which is exerted in part by the organic matrix embedded in the mineralized part of the skeleton. This organic matrix consists of proteins and glycoproteins whose carbohydrate component is specifically involved in the control mechanisms. The saccharide moiety of the organic matrix of the spines of the echinoid Paracentrotus lividus was characterized using enzyme-linked lectin assays (ELLAs). O-glycoproteins, different types of complex N-glycoproteins, and terminal sialic acids were detected. Sialic acids are known to interact with Ca ions and could play an important role in the mineralization process. Some of the carbohydrate components detected by ELLAs as well as two organic matrix proteins (SM30 and SM50) were localized within different subregions of the spine skeleton using field-emission scanning electron microscopy. The mappings show that some of these components are not homogeneously distributed in the different skeletal subregions. For example, some N-glycoproteins were preferentially located in the putative amorphous subregion of the skeleton, whereas some O-glycoproteins were localized in the subregion where skeletal growth is inhibited. These results suggest that the biological control exerted on the skeletal properties can be partly modulated by local differences in the organic matrix composition. Copyright 2001 Academic Press.

  19. 30 CFR 27.22 - Methane detector component.

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... 30 Mineral Resources 1 2012-07-01 2012-07-01 false Methane detector component. 27.22 Section 27.22... detector component. (a) A methane detector component shall be suitably constructed for incorporation in or... detector shall include: (1) A method of continuous sampling of the atmosphere in which it functions. (2) A...

  20. 30 CFR 27.22 - Methane detector component.

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... 30 Mineral Resources 1 2014-07-01 2014-07-01 false Methane detector component. 27.22 Section 27.22... detector component. (a) A methane detector component shall be suitably constructed for incorporation in or... detector shall include: (1) A method of continuous sampling of the atmosphere in which it functions. (2) A...

  1. 30 CFR 27.22 - Methane detector component.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... 30 Mineral Resources 1 2011-07-01 2011-07-01 false Methane detector component. 27.22 Section 27.22... detector component. (a) A methane detector component shall be suitably constructed for incorporation in or... detector shall include: (1) A method of continuous sampling of the atmosphere in which it functions. (2) A...

  2. 30 CFR 27.22 - Methane detector component.

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... 30 Mineral Resources 1 2013-07-01 2013-07-01 false Methane detector component. 27.22 Section 27.22... detector component. (a) A methane detector component shall be suitably constructed for incorporation in or... detector shall include: (1) A method of continuous sampling of the atmosphere in which it functions. (2) A...

  3. Enantiomer-specific analysis of multi-component mixtures by correlated electron imaging-ion mass spectrometry

    NASA Astrophysics Data System (ADS)

    Fanood, Mohammad M. Rafiee; Ram, N. Bhargava; Lehmann, C. Stefan; Powis, Ivan; Janssen, Maurice H. M.

    2015-06-01

    Simultaneous, enantiomer-specific identification of chiral molecules in multi-component mixtures is extremely challenging. Many established techniques for single-component analysis fail to provide selectivity in multi-component mixtures and lack sensitivity for dilute samples. Here we show how enantiomers may be differentiated by mass-selected photoelectron circular dichroism using an electron-ion coincidence imaging spectrometer. As proof of concept, vapours containing ~1% of two chiral monoterpene molecules, limonene and camphor, are irradiated by a circularly polarized femtosecond laser, resulting in multiphoton near-threshold ionization with little molecular fragmentation. Large chiral asymmetries (2-4%) are observed in the mass-tagged photoelectron angular distributions. These asymmetries switch sign according to the handedness (R- or S-) of the enantiomer in the mixture and scale with enantiomeric excess of a component. The results demonstrate that mass spectrometric identification of mixtures of chiral molecules and quantitative determination of enantiomeric excess can be achieved in a table-top instrument.

  4. 30 CFR 36.32 - Electrical components and systems.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... 30 Mineral Resources 1 2011-07-01 2011-07-01 false Electrical components and systems. 36.32... TRANSPORTATION EQUIPMENT Construction and Design Requirements § 36.32 Electrical components and systems. (a) Electrical components on mobile diesel-powered transportation equipment shall be certified or approved under...

  5. 30 CFR 36.32 - Electrical components and systems.

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... 30 Mineral Resources 1 2014-07-01 2014-07-01 false Electrical components and systems. 36.32... TRANSPORTATION EQUIPMENT Construction and Design Requirements § 36.32 Electrical components and systems. (a) Electrical components on mobile diesel-powered transportation equipment shall be certified or approved under...

  6. 30 CFR 36.32 - Electrical components and systems.

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... 30 Mineral Resources 1 2013-07-01 2013-07-01 false Electrical components and systems. 36.32... TRANSPORTATION EQUIPMENT Construction and Design Requirements § 36.32 Electrical components and systems. (a) Electrical components on mobile diesel-powered transportation equipment shall be certified or approved under...

  7. 30 CFR 36.32 - Electrical components and systems.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... 30 Mineral Resources 1 2010-07-01 2010-07-01 false Electrical components and systems. 36.32... TRANSPORTATION EQUIPMENT Construction and Design Requirements § 36.32 Electrical components and systems. (a) Electrical components on mobile diesel-powered transportation equipment shall be certified or approved under...

  8. 30 CFR 36.32 - Electrical components and systems.

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... 30 Mineral Resources 1 2012-07-01 2012-07-01 false Electrical components and systems. 36.32... TRANSPORTATION EQUIPMENT Construction and Design Requirements § 36.32 Electrical components and systems. (a) Electrical components on mobile diesel-powered transportation equipment shall be certified or approved under...

  9. The enamel protein amelotin is a promoter of hydroxyapatite mineralization.

    PubMed

    Abbarin, Nastaran; San Miguel, Symone; Holcroft, James; Iwasaki, Kengo; Ganss, Bernhard

    2015-05-01

    Amelotin (AMTN) is a recently discovered protein that is specifically expressed during the maturation stage of dental enamel formation. It is localized at the interface between the enamel surface and the apical surface of ameloblasts. AMTN knock-out mice have hypomineralized enamel, whereas transgenic mice overexpressing AMTN have a compact but disorganized enamel hydroxyapatite (HA) microstructure, indicating a possible involvement of AMTN in regulating HA mineralization directly. In this study, we demonstrated that recombinant human (rh) AMTN dissolved in a metastable buffer system, based on light scattering measurements, promotes HA precipitation. The mineral precipitates were characterized by scanning and transmission electron microscopy and electron diffraction. Colloidal gold immunolabeling of AMTN in the mineral deposits showed that protein molecules were associated with HA crystals. The binding affinity of rh-AMTN to HA was found to be comparable to that of amelogenin, the major protein of the forming enamel matrix. Overexpression of AMTN in mouse calvaria cells also increased the formation of calcium deposits in the culture medium. Overexpression of AMTN during the secretory stage of enamel formation in vivo resulted in rapid and uncontrolled enamel mineralization. Site-specific mutagenesis of the potential serine phosphorylation motif SSEEL reduced the in vitro mineral precipitation to less than 25%, revealing that this motif is important for the HA mineralizing function of the protein. A synthetic short peptide containing the SSEEL motif was only able to facilitate mineralization in its phosphorylated form ((P)S(P) SEEL), indicating that this motif is necessary but not sufficient for the mineralizing properties of AMTN. These findings demonstrate that AMTN has a direct influence on biomineralization by promoting HA mineralization and suggest a critical role for AMTN in the formation of the compact aprismatic enamel surface layer during the maturation

  10. Clay minerals in primitive meteorites and interplanetary dust 2. Smectites and micas

    NASA Technical Reports Server (NTRS)

    Keller, L. P.; Zolensky, M. E.

    1991-01-01

    The classification is briefly summarized of stony meteorites and cosmic dust, and the mineralogy and chemistry is described of serpentine group minerals. The occurrence of smectites and micas in extraterrestrial materials is examined. The characterization of fine grained minerals in meteorites and IDPs relies heavily on electron beam instruments, especially the transmission electron microscope (TEM). Typically, phyllosilicates are identified by a combination of high resolution imaging of basal spacings, electron diffraction, and chemical analysis. Smectites can be difficult to differentiate from micas because the smectites lose their interlayer water and the interlayer partly collapse in the high vacuum of the TEM.

  11. Carbon Nanotubes: Molecular Electronic Components

    NASA Technical Reports Server (NTRS)

    Srivastava, Deepak; Saini, Subhash; Menon, Madhu

    1997-01-01

    The carbon Nanotube junctions have recently emerged as excellent candidates for use as the building blocks in the formation of nanoscale molecular electronic networks. While the simple joint of two dissimilar tubes can be generated by the introduction of a pair of heptagon-pentagon defects in an otherwise perfect hexagonal graphene sheet, more complex joints require other mechanisms. In this work we explore structural characteristics of complex 3-point junctions of carbon nanotubes using a generalized tight-binding molecular-dynamics scheme. The study of pi-electron local densities of states (LDOS) of these junctions reveal many interesting features, most prominent among them being the defect-induced states in the gap.

  12. Time structure of the EAS electron and muon components measured by the KASCADE Grande experiment

    NASA Astrophysics Data System (ADS)

    Apel, W. D.; Arteaga, J. C.; Badea, A. F.; Bekk, K.; Bertaina, M.; Blümer, J.; Bozdog, H.; Brancus, I. M.; Brüggemann, M.; Buchholz, P.; Cantoni, E.; Chiavassa, A.; Cossavella, F.; Daumiller, K.; de Souza, V.; Di Pierro, F.; Doll, P.; Engel, R.; Engler, J.; Finger, M.; Fuhrmann, D.; Ghia, P. L.; Gils, H. J.; Glasstetter, R.; Grupen, C.; Haungs, A.; Heck, D.; Hörandel, J. R.; Huege, T.; Isar, P. G.; Kampert, K.-H.; Kickelbick, D.; Klages, H. O.; Kolotaev, Y.; Luczak, P.; Mathes, H. J.; Mayer, H. J.; Meurer, C.; Milke, J.; Mitrica, B.; Morello, C.; Navarra, G.; Nehls, S.; Oehlschläger, J.; Ostapchenko, S.; Over, S.; Petcu, M.; Pierog, T.; Plewnia, S.; Rebel, H.; Roth, M.; Schieler, H.; Sima, O.; Stümpert, M.; Toma, G.; Trinchero, G. C.; Ulrich, H.; van Buren, J.; Walkowiak, W.; Weindl, A.; Wochele, J.; Zabierowski, J.

    2008-06-01

    Extensive air showers measured by the KASCADE-Grande experiment at the Forschungszentrum Karlsruhe are studied with respect to the arrival times of electrons and muons at observation level. The mean and the spread of the arrival time distributions have been used to determine the average time profile of the electromagnetic and muonic shower disk. For core distances R>200m particles of the muonic shower component arrive on average earlier at observation level than particles of the electromagnetic shower component. The difference increases with the core distance from Δ=(12.9±0.2)ns at R>200m to Δ=(47±1)ns at R=500m, where the width of the muonic and electromagnetic shower disks are comparable. This difference in arrival time is used to separate the electrons and muons dependent on the distance from the shower center. This is intended to be used by experiments with time resolving detectors.

  13. 30 CFR 75.1103-7 - Electrical components; permissibility requirements.

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... 30 Mineral Resources 1 2012-07-01 2012-07-01 false Electrical components; permissibility... Protection § 75.1103-7 Electrical components; permissibility requirements. The electrical components of each... dust when the electrical power is deenergized as required by § 75.313, but these components shall be...

  14. 30 CFR 75.1103-7 - Electrical components; permissibility requirements.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... 30 Mineral Resources 1 2010-07-01 2010-07-01 false Electrical components; permissibility... Protection § 75.1103-7 Electrical components; permissibility requirements. The electrical components of each... dust when the electrical power is deenergized as required by § 75.313, but these components shall be...

  15. 30 CFR 75.1103-7 - Electrical components; permissibility requirements.

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... 30 Mineral Resources 1 2013-07-01 2013-07-01 false Electrical components; permissibility... Protection § 75.1103-7 Electrical components; permissibility requirements. The electrical components of each... dust when the electrical power is deenergized as required by § 75.313, but these components shall be...

  16. 30 CFR 75.1103-7 - Electrical components; permissibility requirements.

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... 30 Mineral Resources 1 2014-07-01 2014-07-01 false Electrical components; permissibility... Protection § 75.1103-7 Electrical components; permissibility requirements. The electrical components of each... dust when the electrical power is deenergized as required by § 75.313, but these components shall be...

  17. 30 CFR 75.1103-7 - Electrical components; permissibility requirements.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... 30 Mineral Resources 1 2011-07-01 2011-07-01 false Electrical components; permissibility... Protection § 75.1103-7 Electrical components; permissibility requirements. The electrical components of each... dust when the electrical power is deenergized as required by § 75.313, but these components shall be...

  18. Low energy electron induced fragmentation and reactions of DNA and its molecular components

    NASA Astrophysics Data System (ADS)

    Bass, Andrew

    2005-05-01

    Much research has been stimulated by the recognition that ionizing radiation can, in condensed matter, generate large numbers of secondary electrons with energies less than 20 eV [1] and by the experimental demonstration that such electrons may induce both single and double strand breaks in plasmid DNA [2]. Identifying the underlying mechanisms involves several research methodologies, from further experiments with DNA to studies of the electron interaction with the component `sub-units' of DNA in both the gas and condensed phases [3]. In particular, understanding electron-induced strand break damage, the type of damage most difficult for organisms to repair, necessitates study of the sub-units of DNA back-bone, and here Tetrahyrofuran (THF) and its derivatives, provide a useful model for the furyl ring at the centre of the deoxyribose sugar. In this contribution, we review with particular reference to DNA and related molecules, the use of electron spectroscopy and mass spectrometry to study electron-induced fragmentation and reactions in thin molecular solids. We describe a newly completed instrument that combines laser post-ionization with a time-of-flight mass analyzer for highly sensitive ion and neutral detection. Use of the instrument is illustrated with results for THF and derivatives. Anion desorption measurements reveal the role of transient negative ions (TNI) and Dissociative Electron Attachment in significant molecular fragmentation and permit effective cross sections for this electron-induced damage to be obtained. The neutral yield functions also illustrate the importance of TNI, mirroring features seen in recently measured cross sections for electron induced aldehyde production in THF [4]. 1. J. A. Laverne and S. M. Pimblott, Radiat. Res. 141, 208 (1995) 2. B. Boudaiffa, et al, Science 287, 1658 (2000) 3. L. Sanche. Physica Scripta. 68, C108, (2003) 4. S.-P. Breton, et al.,J. Chem. Phys. 121, 11240 (2004)

  19. Quantitative determination of the mineral distribution in different collagen zones of calcifying tendon using high voltage electron microscopic tomography

    NASA Technical Reports Server (NTRS)

    McEwen, B. F.; Song, M. J.; Landis, W. J.

    1991-01-01

    High voltage electron microscopic tomography was used to make the first quantitative determination of the distribution of mineral between different regions of collagen fibrils undergoing early calcification in normal leg tendons of the domestic turkey, Meleagris gallopavo. The tomographic 3-D reconstruction was computed from a tilt series of 61 different views spanning an angular range of +/- 60 degrees in 2 degrees intervals. Successive applications of an interactive computer operation were used to mask the collagen banding pattern of either hole or overlap zones into separate versions of the reconstruction. In such 3-D volumes, regions specified by the mask retained their original image density while the remaining volume was set to background levels. This approach was also applied to the mineral crystals present in the same volumes to yield versions of the 3-D reconstructions that were masked for both the crystal mass and the respective collagen zones. Density profiles from these volumes contained a distinct peak corresponding only to the crystal mass. A comparison of the integrated density of this peak from each profile established that 64% of the crystals observed were located in the collagen hole zones and 36% were found in the overlap zones. If no changes in crystal stability occur once crystals are formed, this result suggests the possibilities that nucleation of mineral is preferentially and initially associated with the hole zones, nucleation occurs more frequently in the hole zones, the rate of crystal growth is more rapid in the hole zones, or a combination of these alternatives. All lead to the conclusion that the overall accumulation of mineral mass is predominant in the collagen hole zones compared to overlap zones during early collagen fibril calcification.

  20. Flexible Electronic Substrate Film Fabricated Using Natural Clay and Wood Components with Cross-Linking Polymer.

    PubMed

    Takahashi, Kiyonori; Ishii, Ryo; Nakamura, Takashi; Suzuki, Asami; Ebina, Takeo; Yoshida, Manabu; Kubota, Munehiro; Nge, Thi Thi; Yamada, Tatsuhiko

    2017-05-01

    Requirements for flexible electronic substrate are successfully accomplished by green nanocomposite film fabricated with two natural components: glycol-modified biomass lignin and Li + montmorillonite clay. In addition to these major components, a cross-linking polymer between the lignin is incorporated into montmorillonite. Multilayer-assembled structure is formed due to stacking nature of high aspect montmorillonite, resulting in thermal durability up to 573 K, low thermal expansion, and oxygen barrier property below measurable limit. Preannealing for montmorillonite and the cross-linking formation enhance moisture barrier property superior to that of industrial engineering plastics, polyimide. As a result, the film has advantages for electronic film substrate. Furthermore, these properties can be achieved at the drying temperature up to 503 K, while the polyimide films are difficult to fabricate by this temperature. In order to examine its applicability for substrate film, flexible electrodes are finely printed on it and touch sensor device can be constructed with rigid elements on the electrode. In consequence, this nanocomposite film is expected to contribute to production of functional materials, progresses in expansion of biomass usage with low energy consumption, and construction of environmental friendly flexible electronic devices. © 2017 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  1. [The determination of molecular sulphur in Matsesta mineral water and its analog Novonukutskaya mineral water].

    PubMed

    Khutorianskiĭ, V A; Smirnov, A I; Matveev, D A

    2014-01-01

    The method of microcolumn reversed phase high performance liquid chromatography (rp-HPLC) was employed to determine the content of elemental sulphur in mineral waters. The study envisaged the analysis of the samples of sulphide-containing mineral waters Novonukutskaya and Matsesta obtained by the solid phase extraction technique. Based on these data, the authors discuss the origin and the circulation of sulphur in the hydrogen sulphide sources. The elution conditions selected in this study ensured the high-resolution separation of the octasulphur peak from the peaks of allotropic components of the extract whereas the two-wave detection technique allowed to identify the peaks of molecular sulphur.

  2. Microfabrication of passive electronic components with printed graphene-oxide deposition

    NASA Astrophysics Data System (ADS)

    Sinar, Dogan; Knopf, George K.; Nikumb, Suwas

    2014-03-01

    Flexible electronic circuitry is an emerging technology that will significantly impact the future of healthcare and medicine, food safety inspection, environmental monitoring, and public security. Recent advances in drop-on-demand printing technology and electrically conductive inks have enabled simple electronic circuits to be fabricated on mechanically flexible polymers, paper, and bioresorbable silk. Research has shown that graphene, and its derivative formulations, can be used to create low-cost electrically conductive inks. Graphene is a one atom thick two-dimensional layer composed of carbon atoms arranged in a hexagonal lattice forming a material with very high fracture strength, high Young's Modulus, and low electrical resistance. Non-conductive graphene-oxide (GO) inks can also be synthesized from inexpensive graphite powders. Once deposited on the flexible substrate the electrical conductivity of the printed GO microcircuit traces can be restored through thermal reduction. In this paper, a femtosecond laser with a wavelength of 775nm and pulse width of 120fs is used to transform the non-conductive printed GO film into electrically conductive oxygen reduced graphene-oxide (rGO) passive electronic components by the process of laser assisted thermal reduction. The heat affected zone produced during the process was minimized because of the femtosecond pulsed laser. The degree of conductivity exhibited by the microstructure is directly related to the laser power level and exposure time. Although rGO films have higher resistances than pristine graphene, the ability to inkjet print capacitive elements and modify local resistive properties provides for a new method of fabricating sensor microcircuits on a variety of substrate surfaces.

  3. Citrate bridges between mineral platelets in bone

    PubMed Central

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

    2014-01-01

    We provide evidence that citrate anions bridge between mineral platelets in bone and hypothesize that their presence acts to maintain separate platelets with disordered regions between them rather than gradual transformations into larger, more ordered blocks of mineral. To assess this hypothesis, we take as a model for a citrate bridging between layers of calcium phosphate mineral a double salt octacalcium phosphate citrate (OCP-citrate). We use a combination of multinuclear solid-state NMR spectroscopy, powder X-ray diffraction, and first principles electronic structure calculations to propose a quantitative structure for this material, in which citrate anions reside in a hydrated layer, bridging between apatitic layers. To assess the relevance of such a structure in native bone mineral, we present for the first time, to our knowledge, 17O NMR data on bone and compare them with 17O NMR data for OCP-citrate and other calcium phosphate minerals relevant to bone. The proposed structural model that we deduce from this work for bone mineral is a layered structure with thin apatitic platelets sandwiched between OCP-citrate–like hydrated layers. Such a structure can explain a number of known structural features of bone mineral: the thin, plate-like morphology of mature bone mineral crystals, the presence of significant quantities of strongly bound water molecules, and the relatively high concentration of hydrogen phosphate as well as the maintenance of a disordered region between mineral platelets. PMID:24706850

  4. Redox properties of structural Fe in clay minerals. 2. Electrochemical and spectroscopic characterization of electron transfer irreversibility in ferruginous smectite, SWa-1.

    PubMed

    Gorski, Christopher A; Klüpfel, Laura; Voegelin, Andreas; Sander, Michael; Hofstetter, Thomas B

    2012-09-04

    Structural Fe in clay minerals is an important, albeit poorly characterized, redox-active phase found in many natural and engineered environments. This work develops an experimental approach to directly assess the redox properties of a natural Fe-bearing smectite (ferruginous smectite, SWa-1, 12.6 wt % Fe) with mediated electrochemical reduction (MER) and oxidation (MEO). By utilizing a suite of one-electron-transfer mediating compounds to facilitate electron transfer between structural Fe in SWa-1 and a working electrode, we show that the Fe2+/Fe3+ couple in SWa-1 is redox-active over a large range of potentials (from E(H) = -0.63 V to +0.61 V vs SHE). Electrochemical and spectroscopic analyses of SWa-1 samples that were subject to reduction and re-oxidation cycling revealed both reversible and irreversible structural Fe rearrangements that altered the observed apparent standard reduction potential (E(H)(ø)) of structural Fe. E(H)(ø)-values vary by as much as 0.56 V between SWa-1 samples with different redox histories. The wide range of E(H)-values over which SWa-1 is redox-active and redox history-dependent E(H)(ø)-values underscore the importance of Fe-bearing clay minerals as redox-active phases in a wide range of redox regimes.

  5. A mineralogical study in contrasts: highly mineralized whale rostrum and human enamel

    NASA Astrophysics Data System (ADS)

    Li, Zhen; Ai-Jawad, Maisoon; Siddiqui, Samera; Pasteris, Jill D.

    2015-11-01

    The outermost enamel of the human tooth and the rostrum of the whale Mesoplodon densirostris are two highly mineralized tissues that contain over 95 wt.% mineral, i.e., bioapatite. However, the same mineral type (carbonated hydroxylapatite) does not yield the same material properties, as revealed by Raman spectroscopy, scanning electron microscopy, electron microprobe analysis, and synchrotron X-ray diffraction analysis. Overall, the outermost enamel of a tooth has more homogeneous physical and chemical features than the rostrum. Chemical comparison of rostrum and enamel shows bioapatite in the rostrum to be enriched in Na, Mg, CO3, and S, whereas the outermost enamel shows only a slightly enriched Cl concentration. Morphologically, mineral rods (at tens of μm scale), crystallites and prisms (at μm and sub-μm scale), and platelets (at tens of nm scale) all demonstrate less organized texture in the rostrum than in enamel. Such contrasts between two mineralized tissues suggest distinct pathways of biomineralization, e.g., the nature of the equilibrium between mineral and body fluid. This study illustrates the remarkable flexibility of the apatite mineral structure to match its chemical and physical properties to specific biological needs within the same animal or between species.

  6. Shewanella secretes flavins that mediate extracellular electron transfer

    PubMed Central

    Marsili, Enrico; Baron, Daniel B.; Shikhare, Indraneel D.; Coursolle, Dan; Gralnick, Jeffrey A.; Bond, Daniel R.

    2008-01-01

    Bacteria able to transfer electrons to metals are key agents in biogeochemical metal cycling, subsurface bioremediation, and corrosion processes. More recently, these bacteria have gained attention as the transfer of electrons from the cell surface to conductive materials can be used in multiple applications. In this work, we adapted electrochemical techniques to probe intact biofilms of Shewanella oneidensis MR-1 and Shewanella sp. MR-4 grown by using a poised electrode as an electron acceptor. This approach detected redox-active molecules within biofilms, which were involved in electron transfer to the electrode. A combination of methods identified a mixture of riboflavin and riboflavin-5′-phosphate in supernatants from biofilm reactors, with riboflavin representing the dominant component during sustained incubations (>72 h). Removal of riboflavin from biofilms reduced the rate of electron transfer to electrodes by >70%, consistent with a role as a soluble redox shuttle carrying electrons from the cell surface to external acceptors. Differential pulse voltammetry and cyclic voltammetry revealed a layer of flavins adsorbed to electrodes, even after soluble components were removed, especially in older biofilms. Riboflavin adsorbed quickly to other surfaces of geochemical interest, such as Fe(III) and Mn(IV) oxy(hydr)oxides. This in situ demonstration of flavin production, and sequestration at surfaces, requires the paradigm of soluble redox shuttles in geochemistry to be adjusted to include binding and modification of surfaces. Moreover, the known ability of isoalloxazine rings to act as metal chelators, along with their electron shuttling capacity, suggests that extracellular respiration of minerals by Shewanella is more complex than originally conceived. PMID:18316736

  7. Compositional changes of minerals associated with dynamic recrystallizatin

    NASA Astrophysics Data System (ADS)

    Yund, Richard A.; Tullis, Jan

    1991-09-01

    The rate of compositional and isotopic exchange between minerals may be enhanced significantly if the rock is deformed simultaneously. The enhanced exchange rate may result from a reduction in grain size (shorter distance for volume diffusion), dissolution and growth of grains by diffusion creep (pressure solution), or the movement of high-angle grain boundaries through strained grains during recrystallization in the dislocation creep regime. The migration of high-angle grain boundaries provides high diffusivity paths for the rapid exchange of components during recrystallization. The operation of the latter process has been demonstrated by deforming aggregates consisting of two plagioclases (An1 and An79) at 900°C, 1 GPa confining pressure, and a strain rate of ˜2x10-6s-1. The polygonal, recrystallized grains were analyzed using an analytical transmission electron microscope and have a variable but often intermediate composition. At the conditions of these experiments, the volume interdiffusion rate of NaSi/CaAl is too slow to produce any observable chemical change, and microstructural-chemical relations indicate that the contribution from diffusion creep was insignificant except for initially fine-grained (2 10 μm) aggregates. These results indicate that strain-induced recrystallization can be an effective mechanism for enhancing the kinetics of metamorphic reactions and for resetting the isotope systematics of minerals such as feldspars, pyroxenes, and amphiboles.

  8. CO2 Driven Mineral Transformations in Fractured Reservoir

    NASA Astrophysics Data System (ADS)

    Schaef, T.

    2015-12-01

    Engineering fracture systems in low permeable formations to increase energy production, accelerate heat extraction, or to enhance injectivity for storing anthropogenic CO2, is a challenging endeavor. To complicate matters, caprocks, essential components of subsurface reservoirs, need to maintain their sealing integrity in this modified subsurface system. Supercritical CO2 (scCO2), a proposed non-aqueous based working fluid, is capable of driving mineral transformations in fracture environments. Water dissolution in scCO2 significantly impacts the reactivity of this fluid, largely due to the development of thin adsorbed H2O films on the surfaces of exposed rocks and minerals. Adsorbed H2O films are geochemically complex microenvironments that host mineral dissolution and precipitation processes that could be tailored to influence overall formation permeability. Furthermore, manipulating the composition of injected CO2 (e.g., moisture content and/or reactive gases such as O2, NOx, or SOx) could stimulate targeted mineral transformations that enhance or sustain reservoir performance. PNNL has developed specialized experimental techniques that can be used to characterize chemical reactions occurring between minerals and pressurized gases. For example, hydration of a natural shale sample (Woodford Shale) has been characterized by an in situ infrared spectroscopic technique as water partitions from the scCO2 onto the shale. Mineral dissolution and carbonate precipitation reactions were tracked by monitoring changes of Si-O and C-O stretching bands, respectively Structural changes indicated expandable clays in the shale such as montmorillonite are intercalated with scCO2, a process not observed with the non-expandable kaolinite component. Extreme scale ab initio molecular dynamics simulations were used in conjunction with model mineral systems to identify the driving force and mechanism of water films. They showed that the film nucleation and formation on minerals is

  9. Bone Mineral Density in Relation to Metabolic Syndrome Components in Postmenopausal Women With Diabetes Mellitus Type 2

    PubMed

    Bilić-Ćurčić, Ines; Makarović, Sandra; Mihaljević, Ivan; Franceschi, Maja; Jukić, Tomislav

    2017-03-01

    Diabetes mellitus type 2 is associated with greater bone mineral density (BMD) due to obesity, although rapid bone loss observed over time could be explained by elevated chronic inflammation. The objective of this study was to investigate the relationship between central adiposity and hyperinsulinemia, as well as inflammation markers with vertebral and femoral BMD and bone turnover markers in postmenopausal women with type 2 diabetes. Femoral and vertebral BMD, osteocalcin, pyrilinks D, beta-CrossLaps (B-CTx), insulin, C-reactive protein (CRP), fibrinogen and plasminogen activator inhibitor-1 (PAI-1) were measured in 114 postmenopausal female patients with diabetes type 2. The patients of similar age, HbA1c levels and diabetes duration were divided into 2 groups based on their body mass index (BMI) values: lower or equal to 27 kg/m(2) (31 patients) and higher than 27 kg/m(2) (83 patients). Lower levels of osteocalcin (p=0.001), B-CTx (p=0.000007) and pyrilinks D (p=0.0365), and higher femoral BMD (p=0.00006), insulin level (p=0.0002), PAI-1 (p=0.00000) and CRP (p=0.002) were found in the overweight group. There were no signifi cant differences in vertebral BMD and fibrinogen. Osteocalcin and B-CTx showed inverse correlation, and femoral BMD positive correlation with waist circumference, insulin level and PAI-1. This suggests that abdominal obesity and hyperinsulinemia as components of the metabolic syndrome could increase femoral BMD by lowering bone rate. In addition, the only inflammation marker linked with femoral BMD was PAI-1, which is associated with increased mineralization of cortical bone in mouse.

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

    NASA Astrophysics Data System (ADS)

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

    2010-10-01

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

  11. Space Radiation Shielding Studies for Astronaut and Electronic Component Risk Assessment

    NASA Technical Reports Server (NTRS)

    Fuchs, Jordan Robert

    2010-01-01

    The dosimetry component of the Center for Radiation Engineering and Science for Space Exploration (CRESSE) will design, develop and characterize the response of a suite of radiation detectors and supporting instrumentation and electronics with three primary goals that will: (1) Use established space radiation detection systems to characterize the primary and secondary radiation fields existing in the experimental test-bed zones during exposures at particle accelerator facilities. (2) Characterize the responses of newly developed space radiation detection systems in the experimental test-bed zones during exposures at particle accelerator facilities, and (3) Provide CRESSE collaborators with detailed dosimetry information in experimental test-bed zones.

  12. Speciation of individual mineral particles of micrometer size by the combined use of attenuated total reflectance-Fourier transform-infrared imaging and quantitative energy-dispersive electron probe X-ray microanalysis techniques.

    PubMed

    Jung, Hae-Jin; Malek, Md Abdul; Ryu, JiYeon; Kim, BoWha; Song, Young-Chul; Kim, HyeKyeong; Ro, Chul-Un

    2010-07-15

    Our previous work demonstrated for the first time the potential of the combined use of two techniques, attenuated total reflectance FT-IR (ATR-FT-IR) imaging and a quantitative energy-dispersive electron probe X-ray microanalysis, low-Z particle EPMA, for the characterization of individual aerosol particles. In this work, the speciation of mineral particles was performed on a single particle level for 24 mineral samples, including kaolinite, montmorillonite, vermiculite, talc, quartz, feldspar, calcite, gypsum, and apatite, by the combined use of ATR-FT-IR imaging and low-Z particle EPMA techniques. These two single particle analytical techniques provide complementary information, the ATR-FT-IR imaging on mineral types and low-Z particle EPMA on the morphology and elemental concentrations, on the same individual particles. This work demonstrates that the combined use of the two single particle analytical techniques can powerfully characterize externally heterogeneous mineral particle samples in detail and has great potential for the characterization of airborne mineral dust particles.

  13. Characteristics of minerals in vesicles produced by human osteoblasts hFOB 1.19 and osteosarcoma Saos-2 cells stimulated for mineralization.

    PubMed

    Strzelecka-Kiliszek, Agnieszka; Bozycki, Lukasz; Mebarek, Saida; Buchet, Rene; Pikula, Slawomir

    2017-06-01

    Bone cells control initial steps of mineralization by producing extracellular matrix (ECM) proteins and releasing vesicles that trigger apatite nucleation. Using transmission electron microscopy with energy dispersive X-ray microanalysis (TEM-EDX) we compared the quality of minerals in vesicles produced by two distinct human cell lines: fetal osteoblastic hFOB 1.19 and osteosarcoma Saos-2. Both cell lines, subjected to osteogenic medium with ascorbic acid (AA) and β-glycerophosphate (β-GP), undergo the entire osteoblastic differentiation program from proliferation to mineralization, produce the ECM and spontaneously release vesicles. We observed that Saos-2 cells mineralized better than hFOB 1.19, as probed by Alizarin Red-S (AR-S) staining, tissue nonspecific alkaline phosphatase (TNAP) activity and by analyzing the composition of minerals in vesicles. Vesicles released from Saos-2 cells contained and were surrounded by more minerals than vesicles released from hFOB 1.19. In addition, there were more F and Cl substituted apatites in vesicles from hFOB 1.19 than in those from Saos-2 cells as determined by ion ratios. Saos-2 and h-FOB 1.19 cells revealed distinct mineralization profiles, indicating that the process of mineralization may proceed differently in various types of cells. Our findings suggest that TNAP activity is correlated with the relative proportions of mineral-filled vesicles and mineral-surrounded vesicles. The origin of vesicles and their properties predetermine the onset of mineralization at the cellular level. Copyright © 2017 Elsevier Inc. All rights reserved.

  14. Sensor fusion of phase measuring profilometry and stereo vision for three-dimensional inspection of electronic components assembled on printed circuit boards.

    PubMed

    Hong, Deokhwa; Lee, Hyunki; Kim, Min Young; Cho, Hyungsuck; Moon, Jeon Il

    2009-07-20

    Automatic optical inspection (AOI) for printed circuit board (PCB) assembly plays a very important role in modern electronics manufacturing industries. Well-developed inspection machines in each assembly process are required to ensure the manufacturing quality of the electronics products. However, generally almost all AOI machines are based on 2D image-analysis technology. In this paper, a 3D-measurement-method-based AOI system is proposed consisting of a phase shifting profilometer and a stereo vision system for assembled electronic components on a PCB after component mounting and the reflow process. In this system information from two visual systems is fused to extend the shape measurement range limited by 2pi phase ambiguity of the phase shifting profilometer, and finally to maintain fine measurement resolution and high accuracy of the phase shifting profilometer with the measurement range extended by the stereo vision. The main purpose is to overcome the low inspection reliability problem of 2D-based inspection machines by using 3D information of components. The 3D shape measurement results on PCB-mounted electronic components are shown and compared with results from contact and noncontact 3D measuring machines. Based on a series of experiments, the usefulness of the proposed sensor system and its fusion technique are discussed and analyzed in detail.

  15. Heterogeneity of the electron exchange capacity of kitchen waste compost-derived humic acids based on fluorescence components.

    PubMed

    Yuan, Ying; Tan, Wen-Bing; He, Xiao-Song; Xi, Bei-Dou; Gao, Ru-Tai; Zhang, Hui; Dang, Qiu-Ling; Li, Dan

    2016-11-01

    Composting is widely used for recycling of kitchen waste to improve soil properties, which is mainly attributed to the nutrient and structural functions of compost-derived humic acids (HAs). However, the redox properties of compost-derived HAs are not fully explored. Here, a unique framework is employed to investigate the electron exchange capacity (EEC) of HAs during kitchen waste composting. Most components of compost-derived HAs hold EEC, but nearly two-thirds of them are found to be easily destroyed by Shewanella oneidensis MR-1 and thus result in an EEC lower than the electron - donating capacity in compost-derived HAs. Fortunately, a refractory component also existed within compost-derived HAs and could serve as a stable and effective electron shuttle to promote the MR-1 involved in Fe(III) reduction, and its EEC was significantly correlated with the aromaticity and the amount of quinones. Nevertheless, with the increase of composting time, the EEC of the refractory component did not show an increasing trend. These results implied that there was an optimal composting time to maximize the production of HAs with more refractory and redox molecules. Recognition of the heterogeneity of EEC of the compost-derived HAs enables an efficient utilization of the composts for a variety of environmental applications. Graphical abstract Microbial reduction of compost-derived HAs.

  16. Assessment of the geoavailability of trace elements from minerals in mine wastes: analytical techniques and assessment of selected copper minerals

    USGS Publications Warehouse

    Driscoll, Rhonda; Hageman, Phillip L.; Benzel, William M.; Diehl, Sharon F.; Adams, David T.; Morman, Suzette; Choate, LaDonna M.

    2012-01-01

    In this study, four randomly selected copper-bearing minerals were examined—azurite, malachite, bornite, and chalcopyrite. The objectives were to examine and enumerate the crystalline and chemical properties of each of the minerals, to determine which, if any, of the Cu-bearing minerals might adversely affect systems biota, and to provide a multi-procedure reference. Laboratory work included use of computational software for quantifying crystalline and amorphous material and optical and electron imaging instruments to model and project crystalline structures. Chemical weathering, human fluid, and enzyme simulation studies were also conducted. The analyses were conducted systematically: X-ray diffraction and microanalytical studies followed by a series of chemical, bio-leaching, and toxicity experiments.

  17. Hydrocerussite-related minerals and materials: structural principles, chemical variations and infrared spectroscopy.

    PubMed

    Siidra, Oleg; Nekrasova, Diana; Depmeier, Wulf; Chukanov, Nikita; Zaitsev, Anatoly; Turner, Rick

    2018-04-01

    White lead or basic lead carbonate, 2PbCO 3 ·Pb(OH) 2 , the synthetic analogue of hydrocerussite Pb 3 (OH) 2 (CO 3 ) 2 , has been known since antiquity as the most frequently used white paint. A number of different minerals and synthetic materials compositionally and structurally related to hydrocerussite have been described within the last two decades. Herein, a review is given of general structural principles, chemical variations and IR spectra of the rapidly growing family of hydrocerussite-related minerals and synthetic materials. Only structures containing a hydroxo- and/or oxo-component, i.e. which are compositionally directly related with hydrocerussite and `white lead', are reviewed in detail. An essential structural feature of all the considered phases is the presence of electroneutral [PbCO 3 ] 0 cerussite-type layers or sheets. Various interleaved sheets can be incorporated between the cerussite-type sheets. Different sheets are stacked into two-dimensional blocks separated by the stereochemically active 6s 2 lone electron pairs on Pb 2+ cations. Minerals and synthetic materials described herein, together with a number of still hypothetical members, constitute a family of modular structures. Hydrocerussite, abellaite and grootfonteinite can be considered to constitute a merotype family of structures. The remaining hydrocerussite-related structures discussed are built on similar principles, but are more complex. Structural architectures of somersetite and slag phase from Lavrion, Attica, Greece, are unique for oxysalt mineral structures in general. Thus, the whole family of hydrocerussite-related phases can be denoted as a plesiotype family of modular structures. The crystal structures of hydrocerussite from Merehead quarry, Somerset, England, and of its synthetic analogue, both determined from single crystals, are reported here for the first time. The results of the infrared (IR) spectroscopy show that this method is useful for distinguishing several

  18. Time-Resolved Study of Nanomorphology and Nanomechanic Change of Early-Stage Mineralized Electrospun Poly(lactic acid) Fiber by Scanning Electron Microscopy, Raman Spectroscopy and Atomic Force Microscopy

    PubMed Central

    Wang, Mengmeng; Cai, Yin; Zhao, Bo; Zhu, Peizhi

    2017-01-01

    In this study, scanning electron microscopy (SEM), Raman spectroscopy and high-resolution atomic force microscopy (AFM) were used to reveal the early-stage change of nanomorphology and nanomechanical properties of poly(lactic acid) (PLA) fibers in a time-resolved manner during the mineralization process. Electrospun PLA nanofibers were soaked in simulated body fluid (SBF) for different periods of time (0, 1, 3, 5, 7 and 21 days) at 10 °C, much lower than the conventional 37 °C, to simulate the slow biomineralization process. Time-resolved Raman spectroscopy analysis can confirm that apatites were deposited on PLA nanofibers after 21 days of mineralization. However, there is no significant signal change among several Raman spectra before 21 days. SEM images can reveal the mineral deposit on PLA nanofibers during the process of mineralization. In this work, for the first time, time-resolved AFM was used to monitor early-stage nanomorphology and nanomechanical changes of PLA nanofibers. The Surface Roughness and Young’s Modulus of the PLA nanofiber quantitatively increased with the time of mineralization. The electrospun PLA nanofibers with delicate porous structure could mimic the extracellular matrix (ECM) and serve as a model to study the early-stage mineralization. Tested by the mode of PLA nanofibers, we demonstrated that AFM technique could be developed as a potential diagnostic tool to monitor the early onset of pathologic mineralization of soft tissues. PMID:28817096

  19. Imaging and Analytical Approaches for Characterization of Soil Mineral Weathering

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Dohnalkova, Alice; Arey, Bruce; Varga, Tamas

    Soil minerals weathering is the primary natural source of nutrients necessary to sustain productivity in terrestrial ecosystems. Soil microbial communities increase soil mineral weathering and mineral-derived nutrient availability through physical and chemical processes. Rhizosphere, the zone immediately surrounding plant roots, is a biogeochemical hotspot with microbial activity, soil organic matter production, mineral weathering, and secondary phase formation all happening in a small temporally ephemeral zone of steep geochemical gradients. The detailed exploration of the micro-scale rhizosphere is essential to our better understanding of large-scale processes in soils, such as nutrient cycling, transport and fate of soil components, microbial-mineral interactions, soilmore » erosion, soil organic matter turnover and its molecular-level characterization, and predictive modeling.« less

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

    PubMed

    Vasanthakumar, Balasubramanian; Ravishankar, Honnavar; Subramanian, Sankaran

    2012-01-01

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

  1. Minerals Yearbook, volume I, Metals and Minerals

    USGS Publications Warehouse

    ,

    2018-01-01

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

  2. Alterations in mineral properties of zebrafish skeletal bone induced by liliput dtc232 gene mutation

    NASA Astrophysics Data System (ADS)

    Wang, Xiu-Mei; Cui, Fu-Zhai; Ge, Jun; Ma, Chen

    2003-11-01

    The alterations of mineral properties of bone by gene mutation in the zebrafish, which is associated with abnormal bone mineralization and bone diseases, were reported for the first time in this paper. Transmission electron microscope (TEM), Fourier transform infrared microspectroscopy (FTIRM) and thermogravimetric analysis (TGA) were used to investigate the changes in the mineral. Significant variations of the morphologies of the minerals and the mineral/matrix ratio after liliputdtc232(lil) gene mutation have been observed. The morphologies of the minerals, examined by TEM, revealed that the mutated mineral was in bigger size and the shape was block shaped but not plate shaped. The results of FTIRM indicated that the lil mutant zebrafish skeleton exhibited a greater mineral/matrix ratio (phosphate/matrix=4.86±0.28) than that of wild-type zebrafish bone (phosphate/matrix=4.17±0.67), which was confirmed by TGA analysis. Furthermore, the mineral of lil bone became less mature and crystalline with more ion substitutions. And the selected areas electron diffraction (SAED) patterns showed that the main crystal phases of the two type fishes were both hydroxyapatite. In addition, we have discussed the relationship among the mineral properties, nanomechanical properties and biomineralization process.

  3. Investigation of irradiation effects on highly integrated leading-edge electronic components of diagnostics and control systems for LHD deuterium operation

    NASA Astrophysics Data System (ADS)

    Ogawa, K.; Nishitani, T.; Isobe, M.; Murata, I.; Hatano, Y.; Matsuyama, S.; Nakanishi, H.; Mukai, K.; Sato, M.; Yokota, M.; Kobuchi, T.; Nishimura, T.; Osakabe, M.

    2017-08-01

    High-temperature and high-density plasmas are achieved by means of real-time control, fast diagnostic, and high-power heating systems. Those systems are precisely controlled via highly integrated electronic components, but can be seriously affected by radiation damage. Therefore, the effects of irradiation on currently used electronic components should be investigated for the control and measurement of Large Helical Device (LHD) deuterium plasmas. For the precise estimation of the radiation field in the LHD torus hall, the MCNP6 code is used with the cross-section library ENDF B-VI. The geometry is modeled on the computer-aided design. The dose on silicon, which is a major ingredient of electronic components, over nine years of LHD deuterium operation shows that the gamma-ray contribution is dominant. Neutron irradiation tests were performed in the OKTAVIAN at Osaka University and the Fast Neutron Laboratory at Tohoku University. Gamma-ray irradiation tests were performed at the Nagoya University Cobalt-60 irradiation facility. We found that there are ethernet connection failures of programmable logic controller (PLC) modules due to neutron irradiation with a neutron flux of 3  ×  106 cm-2 s-1. This neutron flux is equivalent to that expected at basement level in the LHD torus hall without a neutron shield. Most modules of the PLC are broken around a gamma-ray dose of 100 Gy. This is comparable with the dose in the LHD torus hall over nine years. If we consider the dose only, these components may survive more than nine years. For the safety of the LHD operation, the electronic components in the torus hall have been rearranged.

  4. Rapid electron transfer by the carbon matrix in natural pyrogenic carbon

    PubMed Central

    Sun, Tianran; Levin, Barnaby D. A.; Guzman, Juan J. L.; Enders, Akio; Muller, David A.; Angenent, Largus T.; Lehmann, Johannes

    2017-01-01

    Surface functional groups constitute major electroactive components in pyrogenic carbon. However, the electrochemical properties of pyrogenic carbon matrices and the kinetic preference of functional groups or carbon matrices for electron transfer remain unknown. Here we show that environmentally relevant pyrogenic carbon with average H/C and O/C ratios of less than 0.35 and 0.09 can directly transfer electrons more than three times faster than the charging and discharging cycles of surface functional groups and have a 1.5 V potential range for biogeochemical reactions that invoke electron transfer processes. Surface functional groups contribute to the overall electron flux of pyrogenic carbon to a lesser extent with greater pyrolysis temperature due to lower charging and discharging capacities, although the charging and discharging kinetics remain unchanged. This study could spur the development of a new generation of biogeochemical electron flux models that focus on the bacteria–carbon–mineral conductive network. PMID:28361882

  5. Electron paramagnetic resonance of natural and gamma-irradiated alunite and kaolin mineral powders

    NASA Astrophysics Data System (ADS)

    Koksal, F.; Koseoglu, R.; Saka, I.; Basaran, E.; Sener, F.

    2004-06-01

    Natural alunite and kaolin minerals obtained from West Anatolia were investigated by electron paramagnetic resonance (EPR) in natural and gamma-irradiated states at room temperature and at 113 K. The paramagnetic centres at ambient temperature in natural alunite were attributed to the (C) over dot H 2OH, (C) over dot O-3(-), (S) over dot O-2(-), (C) over dot O-2(-) and [AlO4 ](0) radicals. In natural kaolin, the paramagnetic centres were attributed to the (C) over dot O-3(-), (S) over dot O-2(-) (C) over dot O-2(-) and [AlO4](0) radicals. The gamma-irradiation does not produce any detectable effects on these radicals. At 113 K, the lines for (C) over dot H2OH could not be observed well, probably due to the anisotropic behaviour of the hyperfine interaction of the methylene protons, but the lines for [AlO4](0) centres were found to be perfectly observable at above 20 mW microwave power in both alunite and kaolin powders before and after gamma-irradiation. The EPR parameters of the observed paramagnetic centres were reported.

  6. Electron- and Photon-stimulated Desorption of Alkali Atoms from Lunar Sample and a Model Mineral Surface

    NASA Technical Reports Server (NTRS)

    Yakshinskiy, B. V.; Madey, T. E.

    2003-01-01

    We report recent results on an investigation of source mechanisms for the origin of alkali atoms in the tenuous planetary atmospheres, with focus on non-thermal processes (photon stimulated desorption (PSD), electron stimulated desorption (ESD), and ion sputtering). Whereas alkaline earth oxides (MgO, CaO) are far more abundant in lunar samples than alkali oxides (Na2O, K2O), the atmosphere of the Moon contains easily measurable concentrations of Na and K, while Ca and Mg are undetected there; traces of Ca have recently been seen in the Moon's atmosphere (10-3 of Na). The experiments have included ESD, PSD and ion sputtering of alkali atoms from model mineral surface (amorphous SiO2) and from a lunar basalt sample obtained from NASA. The comparison is made between ESD and PSD efficiency of monovalent alkalis (Na, K) and divalent alkaline earths (Ba, Ca).The ultrahigh vacuum measurement scheme for ESD and PSD of Na atoms includes a highly sensitive alkali metal detector based on surface ionization, and a time-of-flight technique. For PSD measurements, a mercury arc light source (filtered and chopped) is used. We find that bombardment of the alkali covered surfaces by ultraviolet photons or by low energy electrons (E>4 eV) causes desorption of hot alkali atoms. This results are consistent with the model developed to explain our previous measurements of sodium desorption from a silica surface and from water ice: electron- or photon-induced charge transfer from the substrate to the ionic adsorbate causes formation of a neutral alkali atom in a repulsive configuration, from which desorption occurs. The two-electron charge transfer to cause desorption of divalent alkaline eath ions is a less likely process.The data support the suggestion that PSD by UV solar photons is a dominant source process for alkalis in the tenuous lunar atmosphere.

  7. Problem of the thermodynamic status of the mixed-layer minerals

    USGS Publications Warehouse

    Zen, E.-A.

    1962-01-01

    Minerals that show mixed layering, particularly with the component layers in random sequence, pose problems because they may behave thermodynamically as single phases or as polyphase aggregates. Two operational criteria are proposed for their distinction. The first scheme requires two samples of mixed-layer material which differ only in the proportions of the layers. If each of these two samples are allowed to equilibrate with the same suitably chosen monitoring solution, then the intensive parameters of the solution will be invariant if the mixed-layer sample is a polyphase aggregate, but not otherwise. The second scheme makes use of the fact that portions of many titration curves of clay minerals show constancy of the chemical activities of the components in the equilibrating solutions, suggesting phase separation. If such phase separation occurs for a mixed-layer material, then, knowing the number of independent components in the system, it should be possible to decide on the number of phases the mixed-layer material represents. Knowledge of the phase status of mixed-layer material is essential to the study of the equilibrium relations of mineral assemblages involving such material, because a given mixed-layer mineral will be plotted and treated differently on a phase diagram, depending on whether it is a single phase or a polyphase aggregate. Extension of the titration technique to minerals other than the mixed-layer type is possible. In particular, this method may be used to determine if cryptoperthites and peristerites are polyphase aggregates. In general, for any high-order phase separation, the method may be used to decide just at what point in this continuous process the system must be regarded operationally as a polyphase aggregate. ?? 1962.

  8. Metacarpal head biomechanics: a comparative backscattered electron image analysis of trabecular bone mineral density in Pan troglodytes, Pongo pygmaeus, and Homo sapiens.

    PubMed

    Zeininger, Angel; Richmond, Brian G; Hartman, Gideon

    2011-06-01

    Great apes and humans use their hands in fundamentally different ways, but little is known about joint biomechanics and internal bone variation. This study examines the distribution of mineral density in the third metacarpal heads in three hominoid species that differ in their habitual joint postures and loading histories. We test the hypothesis that micro-architectural properties relating to bone mineral density reflect habitual joint use. The third metacarpal heads of Pan troglodytes, Pongo pygmaeus, and Homo sapiens were sectioned in a sagittal plane and imaged using backscattered electron microscopy (BSE-SEM). For each individual, 72 areas of subarticular cortical (subchondral) and trabecular bone were sampled from within 12 consecutive regions of the BSE-SEM images. In each area, gray levels (representing relative mineralization density) were quantified. Results show that chimpanzee, orangutan, and human metacarpal III heads have different gray level distributions. Weighted mean gray levels (WMGLs) in the chimpanzee showed a distinct pattern in which the 'knuckle-walking' regions (dorsal) and 'climbing' regions (palmar) are less mineralized, interpreted to reflect elevated remodeling rates, than the distal regions. Pongo pygmaeus exhibited the lowest WMGLs in the distal region, suggesting elevated remodeling rates in this region, which is loaded during hook grip hand postures associated with suspension and climbing. Differences among regions within metacarpal heads of the chimpanzee and orangutan specimens are significant (Kruskal-Wallis, p < 0.001). In humans, whose hands are used for manipulation as opposed to locomotion, mineralization density is much more uniform throughout the metacarpal head. WMGLs were significantly (p < 0.05) lower in subchondral compared to trabecular regions in all samples except humans. This micro-architectural approach offers a means of investigating joint loading patterns in primates and shows significant differences in

  9. JPL preferred parts list: Reliable electronic components

    NASA Technical Reports Server (NTRS)

    Covey, R. E.; Scott, W. R.; Hess, L. M.; Steffy, T. G.; Stott, F. R.

    1982-01-01

    The JPL Preferred Parts List was prepared to provide a basis for selection of electronic parts for JPL spacecraft programs. Supporting tests for the listed parts were designed to comply with specific spacecraft environmental requirements. The list tabulates the electronic, magnetic, and electromechanical parts applicable to all JPL electronic equipment wherein reliability is a major concern. The parts listed are revelant to equipment supplied by subcontractors as well as fabricated at the laboratory.

  10. 30 CFR 7.506 - Breathable air components.

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... 30 Mineral Resources 1 2014-07-01 2014-07-01 false Breathable air components. 7.506 Section 7.506... APPROVAL OF MINING PRODUCTS TESTING BY APPLICANT OR THIRD PARTY Refuge Alternatives § 7.506 Breathable air components. (a) Breathable air shall be supplied by compressed air cylinders, compressed breathable-oxygen...

  11. 30 CFR 7.506 - Breathable air components.

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... 30 Mineral Resources 1 2012-07-01 2012-07-01 false Breathable air components. 7.506 Section 7.506... APPROVAL OF MINING PRODUCTS TESTING BY APPLICANT OR THIRD PARTY Refuge Alternatives § 7.506 Breathable air components. (a) Breathable air shall be supplied by compressed air cylinders, compressed breathable-oxygen...

  12. 30 CFR 7.506 - Breathable air components.

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... 30 Mineral Resources 1 2013-07-01 2013-07-01 false Breathable air components. 7.506 Section 7.506... APPROVAL OF MINING PRODUCTS TESTING BY APPLICANT OR THIRD PARTY Refuge Alternatives § 7.506 Breathable air components. (a) Breathable air shall be supplied by compressed air cylinders, compressed breathable-oxygen...

  13. Electron spin resonance characterization of radical components in irradiated black pepper skin and core

    NASA Astrophysics Data System (ADS)

    Yamaoki, Rumi; Kimura, Shojiro; Ohta, Masatoshi

    2011-11-01

    Characteristics of free radical components of irradiated black pepper fruit (skin) and the pepper seed (core) were analyzed using electron spin resonance. A weak signal near g=2.005 was observed in black pepper before irradiation. Complex spectra near g=2.005 with three lines (the skin) or seven lines (the core) were observed in irradiated black pepper (both end line width; ca. 6.8 mT). The spectral intensities decreased considerably at 30 days after irradiation, and continued to decrease steadily thereafter. The spectra simulated on the basis of the content and the stability of radical components derived from plant constituents, including fiber, starch, polyphenol, mono- and disaccharide, were in good agreement with the observed spectra. Analysis showed that the signal intensities derived from fiber in the skin for an absorbed dose were higher, and the rates of decrease were lower, than that in the core. In particular, the cellulose radical component in the skin was highly stable.

  14. Global stocks of selected mineral-based commodities

    USGS Publications Warehouse

    Wilburn, David R.; Bleiwas, Donald I.; Karl, Nick A.

    2016-12-05

    IntroductionThe U.S. Geological Survey, National Minerals Information Center, analyzes mineral and metal supply chains by identifying and describing major components of mineral and material flows from ore extraction, through intermediate forms, to a final product. This report focuses on an important component of the world’s supply chain: the amounts and global distribution of major consumer, producer, and exchange stocks of selected mineral commodities. In this report, the term “stock” is used instead of “inventory” and refers to accumulations of mined ore, intermediate products, and refined mineral-based commodities that are in a form that meets the agreed-upon specifications of a buyer or processor of intermediate products. These may include certain ores such as bauxite, concentrates, smelter products, and refined metals. Materials sometimes referred to as inventory for accounting purposes, such as ore contained in a deposit or in a leach pile, or materials that need to be further processed before they can be shipped to a consumer, are not considered. Stocks may be held (owned) by consumers, governments, investors, producers, and traders. They may serve as (1) a means to achieve economic, social, and strategic goals through government policies; (2) a secure source of supply to meet demand and to mitigate potential shortages in the supply chain; (3) a hedge to mitigate price volatility; and (4) vehicles for speculative investment.The paucity and uneven reliability of data for stocks of ores and concentrates and for material held by producers, consumers, and merchants hinder the accurate estimating of the size and distribution of this portion of the supply chain for certain commodities. This paper reviews the more visible stocks held in commodity exchange warehouses distributed throughout the world.

  15. Acquisition of electrical signals using commercial electronic components for detection system of Lead ion in distilled water

    NASA Astrophysics Data System (ADS)

    Pujiyanto; Yasin, M.; Rusydi, F.

    2018-03-01

    Development of lead ion detection systems is expected to have an advantage in terms of simplicity of the device and easy for concentration analysis of a lead ion with very high performance. One important part of lead ion detection systems are electrical signal acquisition parts. The electrical signal acquisition part uses the main electronic components: non inverting op-amplifier, instrumentation amplifier, multiplier circuit and logarithmic amplifier. Here will be shown the performance of lead ion detection systems when the existing electrical signal processors use commercial electronic components. The results that can be drawn from this experimental were the lead ion sensor that has been developed can be used to detect lead ions with a sensitivity of 10.48 mV/ppm with the linearity 97.11% and had a measurement range of 0.1 ppm to 80 ppm.

  16. CALCMIN - an EXCEL™ Visual Basic application for calculating mineral structural formulae from electron microprobe analyses

    NASA Astrophysics Data System (ADS)

    Brandelik, Andreas

    2009-07-01

    CALCMIN, an open source Visual Basic program, was implemented in EXCEL™. The program was primarily developed to support geoscientists in their routine task of calculating structural formulae of minerals on the basis of chemical analysis mainly obtained by electron microprobe (EMP) techniques. Calculation programs for various minerals are already included in the form of sub-routines. These routines are arranged in separate modules containing a minimum of code. The architecture of CALCMIN allows the user to easily develop new calculation routines or modify existing routines with little knowledge of programming techniques. By means of a simple mouse-click, the program automatically generates a rudimentary framework of code using the object model of the Visual Basic Editor (VBE). Within this framework simple commands and functions, which are provided by the program, can be used, for example, to perform various normalization procedures or to output the results of the computations. For the clarity of the code, element symbols are used as variables initialized by the program automatically. CALCMIN does not set any boundaries in complexity of the code used, resulting in a wide range of possible applications. Thus, matrix and optimization methods can be included, for instance, to determine end member contents for subsequent thermodynamic calculations. Diverse input procedures are provided, such as the automated read-in of output files created by the EMP. Furthermore, a subsequent filter routine enables the user to extract specific analyses in order to use them for a corresponding calculation routine. An event-driven, interactive operating mode was selected for easy application of the program. CALCMIN leads the user from the beginning to the end of the calculation process.

  17. Universal formulation of second-order generalized Møller-Plesset perturbation theory for a spin-dependent two-component relativistic many-electron Hamiltonian

    NASA Astrophysics Data System (ADS)

    Nakano, Masahiko; Seino, Junji; Nakai, Hiromi

    2017-05-01

    We have derived and implemented a universal formulation of the second-order generalized Møller-Plesset perturbation theory (GMP2) for spin-dependent (SD) two-component relativistic many-electron Hamiltonians, such as the infinite-order Douglas-Kroll-Hess Hamiltonian for many-electron systems, which is denoted as IODKH/IODKH. Numerical assessments for He- and Ne-like atoms and 16 diatomic molecules show that the MP2 correlation energies with IODKH/IODKH agree well with those calculated with the four-component Dirac-Coulomb (DC) Hamiltonian, indicating a systematic improvement on the inclusion of relativistic two-electron terms. The present MP2 scheme for IODKH/IODKH is demonstrated to be computationally more efficient than that for DC.

  18. Green Clay Minerals

    NASA Astrophysics Data System (ADS)

    Velde, B.

    2003-12-01

    part of it is reduced, another is formed. This is the fundamental geochemical aspect of the genesis of green clay minerals; they contain iron in both oxidation states.Unfortunately modern methods of mineral analysis on a microscopic scale, electron microbeam and others, do not allow the determination of the different oxidation states of iron especially for nonstoichiometric minerals. One can use Mössbauer spectral analysis, but the scales of observations are not the same (Mössbauer needing more material); one method used for observations on a microscale, the other on a macroscale. Given the problems of micro- and macroscale observations, oxidation state information is almost excluded from data gathered since the 1980s or so, and hence information concerning the relations of iron reduction and clay genesis must be taken from older studies. A second, much greater problem is that little X-ray diffraction (XRD) work is done on samples which are analyzed chemically by electron microbeam studies. In the past both types of information, structural and chemical, were available for the same sample. Hence not only do we have no precise chemical data for many samples (oxidation state of iron), but there is a rarity of mineral structural information to go along with the incomplete chemistry. This is critical for the study of clay minerals, because slight chemical changes in a clay mineral are frequently accompanied by changes in its structure, especially when one deals with interstratified clay minerals (mica/smectites for example). In fact, the tendency to obtain more and more precision (analysis of a smaller and smaller sized sample) has led to a total loss of mineralogical data. The Heisenberg principle is unwittingly verified by geologists. We know more about a small part of a sample, but we know less about its whole. As a result, the following discussion is based largely upon old data, those which combine iron oxidation states and XRD information.

  19. Comparing Independent Component Analysis with Principle Component Analysis in Detecting Alterations of Porphyry Copper Deposit (case Study: Ardestan Area, Central Iran)

    NASA Astrophysics Data System (ADS)

    Mahmoudishadi, S.; Malian, A.; Hosseinali, F.

    2017-09-01

    The image processing techniques in transform domain are employed as analysis tools for enhancing the detection of mineral deposits. The process of decomposing the image into important components increases the probability of mineral extraction. In this study, the performance of Principal Component Analysis (PCA) and Independent Component Analysis (ICA) has been evaluated for the visible and near-infrared (VNIR) and Shortwave infrared (SWIR) subsystems of ASTER data. Ardestan is located in part of Central Iranian Volcanic Belt that hosts many well-known porphyry copper deposits. This research investigated the propylitic and argillic alteration zones and outer mineralogy zone in part of Ardestan region. The two mentioned approaches were applied to discriminate alteration zones from igneous bedrock using the major absorption of indicator minerals from alteration and mineralogy zones in spectral rang of ASTER bands. Specialized PC components (PC2, PC3 and PC6) were used to identify pyrite and argillic and propylitic zones that distinguish from igneous bedrock in RGB color composite image. Due to the eigenvalues, the components 2, 3 and 6 account for 4.26% ,0.9% and 0.09% of the total variance of the data for Ardestan scene, respectively. For the purpose of discriminating the alteration and mineralogy zones of porphyry copper deposit from bedrocks, those mentioned percentages of data in ICA independent components of IC2, IC3 and IC6 are more accurately separated than noisy bands of PCA. The results of ICA method conform to location of lithological units of Ardestan region, as well.

  20. In Situ Mineralization of Magnetite Nanoparticles in Chitosan Hydrogel

    NASA Astrophysics Data System (ADS)

    Wang, Yongliang; Li, Baoqiang; Zhou, Yu; Jia, Dechang

    2009-09-01

    Based on chelation effect between iron ions and amino groups of chitosan, in situ mineralization of magnetite nanoparticles in chitosan hydrogel under ambient conditions was proposed. The chelation effect between iron ions and amino groups in CS-Fe complex, which led to that chitosan hydrogel exerted a crucial control on the magnetite mineralization, was proved by X-ray photoelectron spectrum. The composition, morphology and size of the mineralized magnetite nanoparticles were characterized by X-ray diffraction, Raman spectroscopy, transmission electron microscopy and thermal gravity. The mineralized nanoparticles were nonstoichiometric magnetite with a unit formula of Fe2.85O4 and coated by a thin layer of chitosan. The mineralized magnetite nanoparticles with mean diameter of 13 nm dispersed in chitosan hydrogel uniformly. Magnetization measurement indicated that superparamagnetism behavior was exhibited. These magnetite nanoparticles mineralized in chitosan hydrogel have potential applications in the field of biotechnology. Moreover, this method can also be used to synthesize other kinds of inorganic nanoparticles, such as ZnO, Fe2O3 and hydroxyapatite.

  1. Mineral resource of the month: lithium

    USGS Publications Warehouse

    Ober, Joyce A.

    2006-01-01

    Lithium, the lightest metallic element, is silvery, white and soft, and highly reactive. It is used most frequently in chemical compounds or traded as mineral concentrates. Its thermal properties make it an ideal component in thermal shock-resistant ceramics, and its electrochemical properties make it an ideal material for several types of batteries.

  2. Structure of chitosan gels mineralized by sorption

    NASA Astrophysics Data System (ADS)

    Modrzejewska, Z.; Skwarczyńska, A.; Douglas, T. E. L.; Biniaś, D.; Maniukiewicz, W.; Sielski, J.

    2015-10-01

    The paper presents the structural studies of mineralized chitosan hydrogels. Hydrogels produced by using sodium beta-glycerophosphate (Na-β-GP) as a neutralizing agent. Mineralization was performed method "post loading", which consisted in sorption to the gels structure Ca ions. In order to obtain - in the structure of gels - compounds similar to the hydroxyapatites present naturally in bone tissue, gels after sorption were modified in: pH 7 buffer and sodium hydrogen phosphate. In order to determine the structural properties of the gels, the following methods were used: infrared spectroscopy with Fourier transformation, FTIR, X-ray diffractometry, XRD, scanning electron microscopy, SEM.

  3. Mineral distributions at the developing tendon enthesis.

    PubMed

    Schwartz, Andrea G; Pasteris, Jill D; Genin, Guy M; Daulton, Tyrone L; Thomopoulos, Stavros

    2012-01-01

    Tendon attaches to bone across a functionally graded interface, "the enthesis". A gradient of mineral content is believed to play an important role for dissipation of stress concentrations at mature fibrocartilaginous interfaces. Surgical repair of injured tendon to bone often fails, suggesting that the enthesis does not regenerate in a healing setting. Understanding the development and the micro/nano-meter structure of this unique interface may provide novel insights for the improvement of repair strategies. This study monitored the development of transitional tissue at the murine supraspinatus tendon enthesis, which begins postnatally and is completed by postnatal day 28. The micrometer-scale distribution of mineral across the developing enthesis was studied by X-ray micro-computed tomography and Raman microprobe spectroscopy. Analyzed regions were identified and further studied by histomorphometry. The nanometer-scale distribution of mineral and collagen fibrils at the developing interface was studied using transmission electron microscopy (TEM). A zone (∼20 µm) exhibiting a gradient in mineral relative to collagen was detected at the leading edge of the hard-soft tissue interface as early as postnatal day 7. Nanocharacterization by TEM suggested that this mineral gradient arose from intrinsic surface roughness on the scale of tens of nanometers at the mineralized front. Microcomputed tomography measurements indicated increases in bone mineral density with time. Raman spectroscopy measurements revealed that the mineral-to-collagen ratio on the mineralized side of the interface was constant throughout postnatal development. An increase in the carbonate concentration of the apatite mineral phase over time suggested possible matrix remodeling during postnatal development. Comparison of Raman-based observations of localized mineral content with histomorphological features indicated that development of the graded mineralized interface is linked to endochondral

  4. Mineral resource of the month: phosphate rock

    USGS Publications Warehouse

    Jasinski, Stephen M.

    2007-01-01

    Phosphate rock minerals provide the only significant global resources of phosphorus, which is an essential element for plant and animal nutrition. Phosphate rock is used primarily as a principal component of nitrogen-phosphorus-potassium fertilizers, but also to produce elemental phosphorus and animal feed.

  5. Microstructural and micromechanical study of a Ti6Al4V component made by electron beam melting

    NASA Astrophysics Data System (ADS)

    Scherillo, F.; Franchitti, S.; Borrelli, R.; Pirozzi, C.; Squillace, A.; Langella, A.; Carrino, L.

    2016-10-01

    Additive Layer Manufacturing is one of the most promising and investigated manufacturing system due to its advantages to produces near net shape components, also with a very complex shape, in a single shot. Among the different techniques now available, the Electron Beam Melting (EBM) is of particular interest in the production of metal components. Particularly the application of this technique to titanium alloys allows to produces components with a very low buy to fly ratio. In the present paper the microstructure attained is accurately described and mini tensile tests performed allowed to understand the fracture behavior of specimen with the specific microstructure realized under static load.

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

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ... patents, and mineral leasing within National Forest Wilderness. 19.8 Section 19.8 Public Lands: Interior... § 19.8 Prospecting, mineral locations, mineral patents, and mineral leasing within National Forest... locations, mineral patents, and mineral leasing within National Forest Wilderness are contained in parts...

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

    PubMed Central

    Vasanthakumar, Balasubramanian; Ravishankar, Honnavar; Subramanian, Sankaran

    2012-01-01

    Environmental concerns regarding the use of certain chemicals in the froth flotation of minerals have led investigators to explore biological entities as potential substitutes for the reagents in vogue. Despite the fact that several microorganisms have been used for the separation of a variety of mineral systems, a detailed characterization of the biochemical molecules involved therein has not been reported so far. In this investigation, the selective flotation of sphalerite from a sphalerite-galena mineral mixture has been achieved using the cellular components of Bacillus species. The key constituent primarily responsible for the flotation of sphalerite has been identified as DNA, which functions as a bio-collector. Furthermore, using reconstitution studies, the obligatory need for the presence of non-DNA components as bio-depressants for galena has been demonstrated. A probable model involving these entities in the selective flotation of sphalerite from the mineral mixture has been discussed. PMID:22768298

  8. 43 CFR 19.8 - Prospecting, mineral locations, mineral patents, and mineral leasing within National Forest...

    Code of Federal Regulations, 2014 CFR

    2014-10-01

    ... 43 Public Lands: Interior 1 2014-10-01 2014-10-01 false Prospecting, mineral locations, mineral patents, and mineral leasing within National Forest Wilderness. 19.8 Section 19.8 Public Lands: Interior... § 19.8 Prospecting, mineral locations, mineral patents, and mineral leasing within National Forest...

  9. 43 CFR 19.8 - Prospecting, mineral locations, mineral patents, and mineral leasing within National Forest...

    Code of Federal Regulations, 2011 CFR

    2011-10-01

    ... 43 Public Lands: Interior 1 2011-10-01 2011-10-01 false Prospecting, mineral locations, mineral patents, and mineral leasing within National Forest Wilderness. 19.8 Section 19.8 Public Lands: Interior... § 19.8 Prospecting, mineral locations, mineral patents, and mineral leasing within National Forest...

  10. 43 CFR 19.8 - Prospecting, mineral locations, mineral patents, and mineral leasing within National Forest...

    Code of Federal Regulations, 2012 CFR

    2012-10-01

    ... 43 Public Lands: Interior 1 2012-10-01 2011-10-01 true Prospecting, mineral locations, mineral patents, and mineral leasing within National Forest Wilderness. 19.8 Section 19.8 Public Lands: Interior... § 19.8 Prospecting, mineral locations, mineral patents, and mineral leasing within National Forest...

  11. 43 CFR 19.8 - Prospecting, mineral locations, mineral patents, and mineral leasing within National Forest...

    Code of Federal Regulations, 2013 CFR

    2013-10-01

    ... 43 Public Lands: Interior 1 2013-10-01 2013-10-01 false Prospecting, mineral locations, mineral patents, and mineral leasing within National Forest Wilderness. 19.8 Section 19.8 Public Lands: Interior... § 19.8 Prospecting, mineral locations, mineral patents, and mineral leasing within National Forest...

  12. Self-ordering and complexity in epizonal mineral deposits

    USGS Publications Warehouse

    Henley, Richard W.; Berger, Byron R.

    2000-01-01

    Giant deposits are relatively rare and develop where efficient metal deposition is spatially focused by repetitive brittle failure in active fault arrays. Some brief case histories are provided for epithermal, replacement, and porphyry mineralization. These highlight how rock competency contrasts and feedback between processes, rather than any single component of a hydrothermal system, govern the size of individual deposits. In turn, the recognition of the probabilistic nature of mineralization provides a firmer foundation through which exploration investment and risk management decisions can be made.

  13. Mineral lung burden of an urban population

    NASA Astrophysics Data System (ADS)

    Paoletti, L.; Falchi, M.; Batisti, D.; Carrieri, M. P.; Petrelli, M. G.; Ciallella, C.; Donelli, G.

    A study was carried out on mineral lung burden in 85 autopsy cases who died accidentally. Subjects of both sexes aged from 15 to 70 years were selected from all the autopsies performed at the Institute of Forensic Medicine in Rome. These subjects were living in an urban area and were not affected by neoplasm diseases. All selected subjects were residing in Rome at the time of their death. Information on years of legal residence in urban areas, smoking habits and occupational history were obtained by interviews with relatives. Lung parenchyma samples were obtained from the right upper lobe. The mineral particulate matter present in the tissue samples was studied by means of analytical transmission electron microscopy (ATEM) techniques: 16 mineral varieties and 22 metallic elements were identified. Smoke, age and residence seem to have influence on the lung burden.

  14. Mineral resource of the month: diatomite

    USGS Publications Warehouse

    ,

    2013-01-01

    The article discusses the properties and applications of the mineral diatomite. According to the author, diatomite is a soft, friable and very fine-grained siliceous sedimentary rock made of the remains of fossilized diatoms. The author adds that its properties make diatomite very useful as a filtration medium and as a component in cement.

  15. Identification of mineral compositions in some renal calculi by FT Raman and IR spectral analysis

    NASA Astrophysics Data System (ADS)

    Tonannavar, J.; Deshpande, Gouri; Yenagi, Jayashree; Patil, Siddanagouda B.; Patil, Nikhil A.; Mulimani, B. G.

    2016-02-01

    We present in this paper accurate and reliable Raman and IR spectral identification of mineral constituents in nine samples of renal calculi (kidney stones) removed from patients suffering from nephrolithiasis. The identified mineral components include Calcium Oxalate Monohydrate (COM, whewellite), Calcium Oxalate Dihydrate (COD, weddellite), Magnesium Ammonium Phosphate Hexahydrate (MAPH, struvite), Calcium Hydrogen Phosphate Dihydrate (CHPD, brushite), Pentacalcium Hydroxy Triphosphate (PCHT, hydroxyapatite) and Uric Acid (UA). The identification is based on a satisfactory assignment of all the observed IR and Raman bands (3500-400 cm- 1) to chemical functional groups of mineral components in the samples, aided by spectral analysis of pure materials of COM, MAPH, CHPD and UA. It is found that the eight samples are composed of COM as the common component, the other mineral species as common components are: MAPH in five samples, PCHT in three samples, COD in three samples, UA in three samples and CHPD in two samples. One sample is wholly composed of UA as a single component; this inference is supported by the good agreement between ab initio density functional theoretical spectra and experimental spectral measurements of both sample and pure material. A combined application of Raman and IR techniques has shown that, where the IR is ambiguous, the Raman analysis can differentiate COD from COM and PCHT from MAPH.

  16. Identification of mineral compositions in some renal calculi by FT Raman and IR spectral analysis.

    PubMed

    Tonannavar, J; Deshpande, Gouri; Yenagi, Jayashree; Patil, Siddanagouda B; Patil, Nikhil A; Mulimani, B G

    2016-02-05

    We present in this paper accurate and reliable Raman and IR spectral identification of mineral constituents in nine samples of renal calculi (kidney stones) removed from patients suffering from nephrolithiasis. The identified mineral components include Calcium Oxalate Monohydrate (COM, whewellite), Calcium Oxalate Dihydrate (COD, weddellite), Magnesium Ammonium Phosphate Hexahydrate (MAPH, struvite), Calcium Hydrogen Phosphate Dihydrate (CHPD, brushite), Pentacalcium Hydroxy Triphosphate (PCHT, hydroxyapatite) and Uric Acid (UA). The identification is based on a satisfactory assignment of all the observed IR and Raman bands (3500-400c m(-1)) to chemical functional groups of mineral components in the samples, aided by spectral analysis of pure materials of COM, MAPH, CHPD and UA. It is found that the eight samples are composed of COM as the common component, the other mineral species as common components are: MAPH in five samples, PCHT in three samples, COD in three samples, UA in three samples and CHPD in two samples. One sample is wholly composed of UA as a single component; this inference is supported by the good agreement between ab initio density functional theoretical spectra and experimental spectral measurements of both sample and pure material. A combined application of Raman and IR techniques has shown that, where the IR is ambiguous, the Raman analysis can differentiate COD from COM and PCHT from MAPH. Copyright © 2015 Elsevier B.V. All rights reserved.

  17. Deciphering Mineral Homeostasis in Barley Seed Transfer Cells at Transcriptional Level.

    PubMed

    Darbani, Behrooz; Noeparvar, Shahin; Borg, Søren

    2015-01-01

    In addition to the micronutrient inadequacy of staple crops for optimal human nutrition, a global downtrend in crop-quality has emerged from intensive breeding for yield. This trend will be aggravated by elevated levels of the greenhouse gas carbon dioxide. Therefore, crop biofortification is inevitable to ensure a sustainable supply of minerals to the large part of human population who is dietary dependent on staple crops. This requires a thorough understanding of plant-mineral interactions due to the complexity of mineral homeostasis. Employing RNA sequencing, we here communicate transfer cell specific effects of excess iron and zinc during grain filling in our model crop plant barley. Responding to alterations in mineral contents, we found a long range of different genes and transcripts. Among them, it is worth to highlight the auxin and ethylene signaling factors Arfs, Abcbs, Cand1, Hps4, Hac1, Ecr1, and Ctr1, diurnal fluctuation components Sdg2, Imb1, Lip1, and PhyC, retroelements, sulfur homeostasis components Amp1, Hmt3, Eil3, and Vip1, mineral trafficking components Med16, Cnnm4, Aha2, Clpc1, and Pcbps, and vacuole organization factors Ymr155W, RabG3F, Vps4, and Cbl3. Our analysis introduces new interactors and signifies a broad spectrum of regulatory levels from chromatin remodeling to intracellular protein sorting mechanisms active in the plant mineral homeostasis. The results highlight the importance of storage proteins in metal ion toxicity-resistance and chelation. Interestingly, the protein sorting and recycling factors Exoc7, Cdc1, Sec23A, and Rab11A contributed to the response as well as the polar distributors of metal-transporters ensuring the directional flow of minerals. Alternative isoform switching was found important for plant adaptation and occurred among transcripts coding for identical proteins as well as transcripts coding for protein isoforms. We also identified differences in the alternative-isoform preference between the treatments

  18. Deciphering Mineral Homeostasis in Barley Seed Transfer Cells at Transcriptional Level

    PubMed Central

    Borg, Søren

    2015-01-01

    In addition to the micronutrient inadequacy of staple crops for optimal human nutrition, a global downtrend in crop-quality has emerged from intensive breeding for yield. This trend will be aggravated by elevated levels of the greenhouse gas carbon dioxide. Therefore, crop biofortification is inevitable to ensure a sustainable supply of minerals to the large part of human population who is dietary dependent on staple crops. This requires a thorough understanding of plant-mineral interactions due to the complexity of mineral homeostasis. Employing RNA sequencing, we here communicate transfer cell specific effects of excess iron and zinc during grain filling in our model crop plant barley. Responding to alterations in mineral contents, we found a long range of different genes and transcripts. Among them, it is worth to highlight the auxin and ethylene signaling factors Arfs, Abcbs, Cand1, Hps4, Hac1, Ecr1, and Ctr1, diurnal fluctuation components Sdg2, Imb1, Lip1, and PhyC, retroelements, sulfur homeostasis components Amp1, Hmt3, Eil3, and Vip1, mineral trafficking components Med16, Cnnm4, Aha2, Clpc1, and Pcbps, and vacuole organization factors Ymr155W, RabG3F, Vps4, and Cbl3. Our analysis introduces new interactors and signifies a broad spectrum of regulatory levels from chromatin remodeling to intracellular protein sorting mechanisms active in the plant mineral homeostasis. The results highlight the importance of storage proteins in metal ion toxicity-resistance and chelation. Interestingly, the protein sorting and recycling factors Exoc7, Cdc1, Sec23A, and Rab11A contributed to the response as well as the polar distributors of metal-transporters ensuring the directional flow of minerals. Alternative isoform switching was found important for plant adaptation and occurred among transcripts coding for identical proteins as well as transcripts coding for protein isoforms. We also identified differences in the alternative-isoform preference between the treatments

  19. Atom exchange between aqueous Fe(II) and structural Fe in clay minerals.

    PubMed

    Neumann, Anke; Wu, Lingling; Li, Weiqiang; Beard, Brian L; Johnson, Clark M; Rosso, Kevin M; Frierdich, Andrew J; Scherer, Michelle M

    2015-03-03

    Due to their stability toward reductive dissolution, Fe-bearing clay minerals are viewed as a renewable source of Fe redox activity in diverse environments. Recent findings of interfacial electron transfer between aqueous Fe(II) and structural Fe in clay minerals and electron conduction in octahedral sheets of nontronite, however, raise the question whether Fe interaction with clay minerals is more dynamic than previously thought. Here, we use an enriched isotope tracer approach to simultaneously trace Fe atom movement from the aqueous phase to the solid ((57)Fe) and from the solid into the aqueous phase ((56)Fe). Over 6 months, we observed a significant decrease in aqueous (57)Fe isotope fraction, with a fast initial decrease which slowed after 3 days and stabilized after about 50 days. For the aqueous (56)Fe isotope fraction, we observed a similar but opposite trend, indicating that Fe atom movement had occurred in both directions: from the aqueous phase into the solid and from the solid into aqueous phase. We calculated that 5-20% of structural Fe in clay minerals NAu-1, NAu-2, and SWa-1 exchanged with aqueous Fe(II), which significantly exceeds the Fe atom layer exposed directly to solution. Calculations based on electron-hopping rates in nontronite suggest that the bulk conduction mechanism previously demonstrated for hematite1 and suggested as an explanation for the significant Fe atom exchange observed in goethite2 may be a plausible mechanism for Fe atom exchange in Fe-bearing clay minerals. Our finding of 5-20% Fe atom exchange in clay minerals indicates that we need to rethink how Fe mobility affects the macroscopic properties of Fe-bearing phyllosilicates and its role in Fe biogeochemical cycling, as well as its use in a variety of engineered applications, such as landfill liners and nuclear repositories.

  20. Indispensable role of biochar-inherent mineral constituents in its environmental applications: A review.

    PubMed

    Xu, Xiaoyun; Zhao, Yinghao; Sima, Jingke; Zhao, Ling; Mašek, Ondřej; Cao, Xinde

    2017-10-01

    Biochar typically consists of both carbon and mineral fractions, and the carbon fraction has been generally considered to determine its properties and applications. Recently, an increasing body of research has demonstrated that mineral components inherent in biochar, such as alkali or alkaline earth metals in the form of carbonates, phosphates, or oxides, could also influence the properties and thus the applications. The review articles published thus far have mainly focused on multiple environmental and agronomic applications of biochar, including carbon sequestration, soil improvement, environmental remediation, etc. This review aims to highlight the indispensable role of the mineral fraction of biochar in these different applications, especially in environmental applications. Specifically, it provides a critical review of current research findings related to the mineral composition of biochar and the effect of the mineral fraction on the physicochemical properties, contaminant sorption, carbon retention and stability, and nutrient bioavailability of biochar. Furthermore, the role of minerals in the emerging applications of biochar, as a precursor for fuel cells, supercapacitors, and photoactive components, is also summarized. Overall, inherent minerals should be fully considered while determining the most appropriate application for any given biochar. A thorough understanding of the role of biochar-bound minerals in different applications will also allow the design or selection of the most suitable biochar for specific applications based on the consideration of feedstock composition, production parameters, and post-treatment. Copyright © 2017 Elsevier Ltd. All rights reserved.

  1. Honeycomb chassis for electronic components

    NASA Technical Reports Server (NTRS)

    Read, W. S.; Stebbins, B. W.

    1977-01-01

    In new electronic chassis support, machined honeycomb members are used to change basic relationship between chassis and support structure. Improved chassis combines internal and external support and heat dissipation by altering chassis internal geometry. Honeycomb materials allow mechanical support and thermal load sharing to be combined at lower weight and lower cost than previous equipment.

  2. Mössbauer study of iron minerals transformations by Fuchsiella ferrireducens

    NASA Astrophysics Data System (ADS)

    Gracheva, M. A.; Chistyakova, N. I.; Antonova, A. V.; Rusakov, V. S.; Zhilina, T. N.; Zavarzina, D. G.

    2017-11-01

    Biogenic transformations of iron-containing minerals synthesized ferrihydrite, magnetite and hydrothermal siderite by anaerobic alkaliphilic bacterium Fuchsiella ferrireducens (strain Z-7101T) were studied by 57Fe Mössbauer spectroscopy. Mössbauer investigations of solid phase samples obtained after microbial transformation were carried out at room temperature and at 82 K. It was found that all tested minerals transformed during bacterial growth. In the presence of synthesized ferrihydrite, added as an electron acceptor, a mixture of large (more than 100 nm) and small (˜5 nm) particles of magnetically ordered phase and siderite was formed. Synthesized magnetite that contains both Fe3+ and Fe2+ forms could serve as electron acceptor as well as an electron donor for F.ferrireducens growth. As a result of its biotransformation, no siderite formation was observed while small particles of magnetite were formed. In the case of the addition of siderite as an electron donor formation of a small amount of a new phase containing Fe2+ caused by recrystallization of siderite during bacterial growth was detected.

  3. Fabrication of mineralized electrospun PLGA and PLGA/gelatin nanofibers and their potential in bone tissue engineering.

    PubMed

    Meng, Z X; Li, H F; Sun, Z Z; Zheng, W; Zheng, Y F

    2013-03-01

    Surface mineralization is an effective method to produce calcium phosphate apatite coating on the surface of bone tissue scaffold which could create an osteophilic environment similar to the natural extracellular matrix for bone cells. In this study, we prepared mineralized poly(D,L-lactide-co-glycolide) (PLGA) and PLGA/gelatin electrospun nanofibers via depositing calcium phosphate apatite coating on the surface of these nanofibers to fabricate bone tissue engineering scaffolds by concentrated simulated body fluid method, supersaturated calcification solution method and alternate soaking method. The apatite products were characterized by the scanning electron microscopy (SEM), Fourier transform-infrared spectroscopy (FT-IR), and X-ray diffractometry (XRD) methods. A large amount of calcium phosphate apatite composed of dicalcium phosphate dihydrate (DCPD), hydroxyapatite (HA) and octacalcium phosphate (OCP) was deposited on the surface of resulting nanofibers in short times via three mineralizing methods. A larger amount of calcium phosphate was deposited on the surface of PLGA/gelatin nanofibers rather than PLGA nanofibers because gelatin acted as nucleation center for the formation of calcium phosphate. The cell culture experiments revealed that the difference of morphology and components of calcium phosphate apatite did not show much influence on the cell adhesion, proliferation and activity. Copyright © 2012 Elsevier B.V. All rights reserved.

  4. 75 FR 28651 - In the Matter of Certain Electronic Paper Towel Dispensing Devices and Components Thereof; Notice...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2010-05-21

    ... INTERNATIONAL TRADE COMMISSION [Inv. No. 337-TA-718] In the Matter of Certain Electronic Paper Towel Dispensing Devices and Components Thereof; Notice of Investigation AGENCY: International Trade... that a complaint was filed with the U.S. International Trade Commission on April 19, 2010, under...

  5. Reaction mechanisms for enhancing carbon dioxide mineral sequestration

    NASA Astrophysics Data System (ADS)

    Jarvis, Karalee Ann

    Increasing global temperature resulting from the increased release of carbon dioxide into the atmosphere is one of the greatest problems facing society. Nevertheless, coal plants remain the largest source of electrical energy and carbon dioxide gas. For this reason, researchers are searching for methods to reduce carbon dioxide emissions into the atmosphere from the combustion of coal. Mineral sequestration of carbon dioxide reacted in electrolyte solutions at 185°C and 2200 psi with olivine (magnesium silicate) has been shown to produce environmentally benign carbonates. However, to make this method feasible for industrial applications, the reaction rate needs to be increased. Two methods were employed to increase the rate of mineral sequestration: reactant composition and concentration were altered independently in various runs. The products were analyzed with complete combustion for total carbon content. Crystalline phases in the product were analyzed with Debye-Scherrer X-ray powder diffraction. To understand the reaction mechanism, single crystals of San Carlos Olivine were reacted in two solutions: (0.64 M NaHCO3/1 M NaCl) and (5.5 M KHCO3) and analyzed with scanning electron microscopy (SEM), transmission electron microscopy (TEM), electron energy loss spectroscopy (EELS), and fluctuation electron microscopy (FEM) to study the surface morphology, atomic crystalline structure, composition and amorphous structure. From solution chemistry studies, it was found that increasing the activity of the bicarbonate ion increased the conversion rate of carbon dioxide to magnesite. The fastest conversion, 60% conversion in one hour, occurred in a solution of 5.5 M KHCO3. The reaction product particles, magnesium carbonate, significantly increased in both number density and size on the coupon when the bicarbonate ion activity was increased. During some experiments reaction vessel corrosion also altered the mineral sequestration mechanism. Nickel ions from vessel

  6. How UV photolysis accelerates the biodegradation and mineralization of sulfadiazine (SD).

    PubMed

    Pan, Shihui; Yan, Ning; Liu, Xinyue; Wang, Wenbing; Zhang, Yongming; Liu, Rui; Rittmann, Bruce E

    2014-11-01

    Sulfadiazine (SD), one of broad-spectrum antibiotics, exhibits limited biodegradation in wastewater treatment due to its chemical structure, which requires initial mono-oxygenation reactions to initiate its biodegradation. Intimately coupling UV photolysis with biodegradation, realized with the internal loop photobiodegradation reactor, accelerated SD biodegradation and mineralization by 35 and 71 %, respectively. The main organic products from photolysis were 2-aminopyrimidine (2-AP), p-aminobenzenesulfonic acid (ABS), and aniline (An), and an SD-photolysis pathway could be identified using C, N, and S balances. Adding An or ABS (but not 2-AP) into the SD solution during biodegradation experiments (no UV photolysis) gave SD removal and mineralization rates similar to intimately coupled photolysis and biodegradation. An SD biodegradation pathway, based on a diverse set of the experimental results, explains how the mineralization of ABS and An (but not 2-AP) provided internal electron carriers that accelerated the initial mono-oxygenation reactions of SD biodegradation. Thus, multiple lines of evidence support that the mechanism by which intimately coupled photolysis and biodegradation accelerated SD removal and mineralization was through producing co-substrates whose oxidation produced electron equivalents that stimulated the initial mono-oxygenation reactions for SD biodegradation.

  7. Work-related musculoskeletal disorders (WMDs) risk assessment at core assembly production of electronic components manufacturing company

    NASA Astrophysics Data System (ADS)

    Yahya, N. M.; Zahid, M. N. O.

    2018-03-01

    This study conducted to assess the work-related musculoskeletal disorders (WMDs) among the workers at core assembly production in an electronic components manufacturing company located in Pekan, Pahang, Malaysia. The study is to identify the WMDs risk factor and risk level. A set of questionnaires survey based on modified Nordic Musculoskeletal Disorder Questionnaires have been distributed to respective workers to acquire the WMDs risk factor identification. Then, postural analysis was conducted in order to measure the respective WMDs risk level. The analysis were based on two ergonomics assessment tools; Rapid Upper Limb Assessment (RULA) and Rapid Entire Body Assessment (REBA). The study found that 30 respondents out of 36 respondents suffered from WMDs especially at shoulder, wrists and lower back. The WMDs risk have been identified from unloading process, pressing process and winding process. In term of the WMDs risk level, REBA and RULA assessment tools have indicated high risk level to unloading and pressing process. Thus, this study had established the WMDs risk factor and risk level of core assembly production in an electronic components manufacturing company at Malaysia environment.

  8. Maghemite Formation via Organics and the Prospect for Maghemite as a Biomarker Mineral on Mars

    NASA Technical Reports Server (NTRS)

    Bishop, Janice; Mancinelli, R. L.; Madsen, M. B.; Zent, A. P.

    2000-01-01

    One of the major questions on Mars is the origin of the magnetic component in the surface material. Our work on maghemite formation suggests that alteration of femhydrite in the presence of organics would provide a plausible formation scenario for this magnetic soil component and further suggests that maghemite might be an important biomarker mineral on Mars. Identification of biomarker minerals is an important aspect of Astrobiology . The iron oxide mineral maghemite is thought to be one of the magnetic components in the Martian surface material; however, it is a rare mineral on the Earth and requires a reducing agent for synthesis. Organic material serves as a reductant in maghemite formation during forest fires on Earth and may play an important role in maghemite formation on Mars through low-temperature heating (e.g., volcanism, impacts). This study involves analysis of magnetite, maghemite and hematite formation under Martian environmental conditions from femhydrite in the presence and absence of organics. A dehydrated version of the mineral femhydrite is thought to be present in Martian soil/dust grains and could have formed at an earlier time on Mars when water was present. Our work indicates that low-temperature alteration of femhydrite in the presence of organic material could be an important mechanism on Mars.

  9. Minerals

    MedlinePlus

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

  10. Mineral transformations associated with goethite reduction by Methanosarcina barkeri

    USGS Publications Warehouse

    Liu, D.; Wang, Hongfang; Dong, H.; Qiu, X.; Dong, X.; Cravotta, C.A.

    2011-01-01

    To investigate the interaction between methanogens and iron-containing minerals in anoxic environments, we conducted batch culture experiments with Methanosarcina barkeri in a phosphate-buffered basal medium (PBBM) to bioreduce structural Fe(III) in goethite with hydrogen as the sole substrate. Fe(II) and methane concentrations were monitored over the course of the bioreduction experiments with wet chemistry and gas chromatography, respectively. Subsequent mineralogical changes were characterized with X-ray diffraction (XRD) and scanning electron microscopy (SEM). In the presence of an electron shuttle anthraquinone-2,6-disulfonate (AQDS), 30% Fe(III) in goethite (weight basis) was reduced to Fe(II). In contrast, only 2% Fe(III) (weight basis) was bioreduced in the absence of AQDS. Most of the bioproduced Fe(II) was incorporated into secondary minerals including dufr??nite and vivianite. Our data implied a dufr??nite-vivianite transformation mechanism where a metastable dufr??nite transformed to a more stable vivianite over extended time in anaerobic conditions. Methanogenesis was greatly inhibited by bioreduction of goethite Fe(III). These results have important implications for the methane flux associated with Fe(III) bioreduction and ferrous iron mineral precipitation in anaerobic soils and sediments. ?? 2011 Elsevier B.V.

  11. Tracking Electron Uptake from a Cathode into Shewanella Cells: Implications for Energy Acquisition from Solid-Substrate Electron Donors

    PubMed Central

    Rajeev, Pournami; Jain, Abhiney; Pirbadian, Sahand; Okamoto, Akihiro; Gralnick, Jeffrey A.; El-Naggar, Mohamed Y.; Nealson, Kenneth H.

    2018-01-01

    ABSTRACT While typically investigated as a microorganism capable of extracellular electron transfer to minerals or anodes, Shewanella oneidensis MR-1 can also facilitate electron flow from a cathode to terminal electron acceptors, such as fumarate or oxygen, thereby providing a model system for a process that has significant environmental and technological implications. This work demonstrates that cathodic electrons enter the electron transport chain of S. oneidensis when oxygen is used as the terminal electron acceptor. The effect of electron transport chain inhibitors suggested that a proton gradient is generated during cathode oxidation, consistent with the higher cellular ATP levels measured in cathode-respiring cells than in controls. Cathode oxidation also correlated with an increase in the cellular redox (NADH/FMNH2) pool determined with a bioluminescence assay, a proton uncoupler, and a mutant of proton-pumping NADH oxidase complex I. This work suggested that the generation of NADH/FMNH2 under cathodic conditions was linked to reverse electron flow mediated by complex I. A decrease in cathodic electron uptake was observed in various mutant strains, including those lacking the extracellular electron transfer components necessary for anodic-current generation. While no cell growth was observed under these conditions, here we show that cathode oxidation is linked to cellular energy acquisition, resulting in a quantifiable reduction in the cellular decay rate. This work highlights a potential mechanism for cell survival and/or persistence on cathodes, which might extend to environments where growth and division are severely limited. PMID:29487241

  12. [Spectrum characteristics of leaching components from co-contaminated loess in ex-situ column washing reaction].

    PubMed

    Fan, Chun-hui; Zhang, Ying-chao; Du, Bo; He, Lei; Wang, Jia-hong

    2015-02-01

    Soil contamination is regarded as one of the most serious issues to humanity all over the world. It is statistically believed that over one-fifth of the farmland, that is 20 million ha, is found to be contaminated by heavy metals in China. And the related issues, caused by soil contamination, of food safety, human health and eco-environmental quality attract much attention by public with more serious contamination than before. The technological approach for soil remediation is widely investigated. The technology of soil washing is effective for contaminants removal, while the treatment procedure might lead to component leaching from soil system, harmful for soil fertility, physicochemical properties and ecological functions. The study of spectral characteristics on leaching component is significant for decision-making of contaminated sites remediation and ecological function recovery, while the related investigation seems weaker nowadays. The paper mainly revealed the leaching characteristics of component from Pb/Cd contaminated loess in the washing process with Ethylene Diamine Tetraacetic Acid (EDTA) in reaction column, and the research objectives included base cations, loess nutrients, clay minerals and organic matter. The variation of clay minerals was analyzed by X-ray diffraction (XRD) and scanning electron microscope (SEM), and 3D-EEM fluorescence spectrum was used for the identification of dissolved organic matter (DOM). The experimental results showed: the leaching component from loess is detected in the washing reaction. The final removal efficiency (240 min) of Pb and Cd from loess are 49. 86% and 62.25%, respectively. The sodium ions and nitrate nitrogen are the most easily leaching component, and little difference of clay minerals is identified before and after washing reaction. The fulvic acid-like (FA-like) material was firstly (10 min) detected around E(ex/em) = 240-250/320-340 and E(ex/em) = 260-290/450-470 in 3D-EEM fluorescence spectrum, and the

  13. Modeling dust as component minerals in the Community Atmosphere Model: development of framework and impact on radiative forcing

    DOE PAGES

    Scanza, R. A.; Mahowald, N.; Ghan, S.; ...

    2014-07-02

    The mineralogy of desert dust is important due to its effect on radiation, clouds and biogeochemical cycling of trace nutrients. This study presents the simulation of dust radiative forcing as a function of both mineral composition and size at the global scale using mineral soil maps for estimating emissions. Externally mixed mineral aerosols in the bulk aerosol module in the Community Atmosphere Model version 4 (CAM4) and internally mixed mineral aerosols in the modal aerosol module in the Community Atmosphere Model version 5.1 (CAM5) embedded in the Community Earth System Model version 1.0.5 (CESM) are speciated into common mineral componentsmore » in place of total dust. The simulations with mineralogy are compared to available observations of mineral atmospheric distribution and deposition along with observations of clear-sky radiative forcing efficiency. Based on these simulations, we estimate the all-sky direct radiative forcing at the top of the atmosphere as +0.05 W m −2 for both CAM4 and CAM5 simulations with mineralogy and compare this both with simulations of dust in release versions of CAM4 and CAM5 (+0.08 and +0.17 W m −2) and of dust with optimized optical properties, wet scavenging and particle size distribution in CAM4 and CAM5, −0.05 and −0.17 W m −2, respectively. The ability to correctly include the mineralogy of dust in climate models is hindered by its spatial and temporal variability as well as insufficient global in-situ observations, incomplete and uncertain source mineralogies and the uncertainties associated with data retrieved from remote sensing methods.« less

  14. Modeling dust as component minerals in the Community Atmosphere Model: development of framework and impact on radiative forcing

    DOE PAGES

    Scanza, Rachel; Mahowald, N.; Ghan, Steven J.; ...

    2015-01-01

    The mineralogy of desert dust is important due to its effect on radiation, clouds and biogeochemical cycling of trace nutrients. This study presents the simulation of dust radiative forcing as a function of both mineral composition and size at the global scale, using mineral soil maps for estimating emissions. Externally mixed mineral aerosols in the bulk aerosol module in the Community Atmosphere Model version 4 (CAM4) and internally mixed mineral aerosols in the modal aerosol module in the Community Atmosphere Model version 5.1 (CAM5) embedded in the Community Earth System Model version 1.0.5 (CESM) are speciated into common mineral componentsmore » in place of total dust. The simulations with mineralogy are compared to available observations of mineral atmospheric distribution and deposition along with observations of clear-sky radiative forcing efficiency. Based on these simulations, we estimate the all-sky direct radiative forcing at the top of the atmosphere as + 0.05 Wm⁻² for both CAM4 and CAM5 simulations with mineralogy. We compare this to the radiative forcing from simulations of dust in release versions of CAM4 and CAM5 (+0.08 and +0.17 Wm⁻²) and of dust with optimized optical properties, wet scavenging and particle size distribution in CAM4 and CAM5, -0.05 and -0.17 Wm⁻², respectively. The ability to correctly include the mineralogy of dust in climate models is hindered by its spatial and temporal variability as well as insufficient global in situ observations, incomplete and uncertain source mineralogies and the uncertainties associated with data retrieved from remote sensing methods.« less

  15. [An electron microscopic study on the RNA component of synaptonemal complexes in spermatocytes of Mus musculus].

    PubMed

    Xing, M; Jing, D Z; Hao, S

    1991-01-01

    The ultrastructural and cytochemical features of synaptonemal complexes (SC) in sections of spermatocytes of Mus musculus were studied under electron microscope. In specimens stained with uranyl acetate and lead citrate the SC was found consisting of three main elements. the lateral element (LE), the central element (CE) and the transverse filament (L-C filament). When stained with the Bernhard's technique, the SC was recognized as a contrasted, tripartite structure which was usually located in the bleached area occupied by the condensed chromatin and composed of highly electron-dense LEs and medium electron-dense CE and L-C filaments. The SC and the LE, stained either by uranyl acetate-lead citrate or by the Bernhard's technique, always showed diameters of about 210 nm and 60 nm, respectively. The results suggest that RNA may be an important component of the SC.

  16. Amyloid substance within stenotic aortic valves promotes mineralization.

    PubMed

    Audet, Audrey; Côté, Nancy; Couture, Christian; Bossé, Yohan; Després, Jean-Pierre; Pibarot, Philippe; Mathieu, Patrick

    2012-10-01

    Accumulation of apolipoproteins may play an important role in the pathobiology of calcific aortic valve disease (CAVD). We aimed to explore the hypothesis that apolipoprotein-derived amyloid could play a role in the development of CAVD. In 70 explanted CAVD valves and 15 control non-calcified aortic valves, we assessed the presence of amyloid by using Congo red staining. Immunohistochemistry was performed to document the presence of apolipoprotein AI (Apo-AI). Apoptosis was documented by terminal deoxynucleotidyl transferase dUTP nick end labelling (TUNEL) studies performed in control and CAVD valves. Control valves were free of amyloid. Deposition of amyloid was detected in all CAVD valves, and the amount was positively correlated with plasma high-density lipoprotein and Apo-AI levels. Apo-AI within CAVD valves co-localized with intense staining of fibrillar amyloid. In turn, deposition of amyloid co-localized with apoptosis near mineralized areas. Isolation of amyloid fibrils confirmed that Apo-AI is a major component of amyloid deposits in CAVD. In vitro, CAVD-derived amyloid extracts increased apoptosis and mineralization of isolated aortic valvular interstitial cells. Apo-AI is a major component of amyloid substance present within CAVD valves. Furthermore, amyloid deposits participate in mineralization in CAVD by promoting apoptosis of valvular interstitial cells. © 2012 Blackwell Publishing Ltd.

  17. An exploration in mineral supply chain mapping using tantalum as an example

    USGS Publications Warehouse

    Soto-Viruet, Yadira; Menzie, W. David; Papp, John F.; Yager, Thomas R.

    2013-01-01

    This report uses the supply chain of tantalum (Ta) to investigate the complexity of mineral and metal supply chains in general and show how they can be mapped. A supply chain is made up of all the manufacturers, suppliers, information networks, and so forth, that provide the materials and parts that go into making up a final product. The mineral portion of the supply chain begins with mineral material in the ground (the ore deposit); extends through a series of processes that include mining, beneficiation, processing (smelting and refining), semimanufacture, and manufacture; and continues through transformation of the mineral ore into concentrates, refined mineral commodities, intermediate forms (such as metals and alloys), component parts, and, finally, complex products. This study analyses the supply chain of tantalum beginning with minerals in the ground to many of the final goods that contain tantalum.

  18. Mineral sulphide-lime reactions and effect of CaO/C mole ratio during carbothermic reduction of complex mineral sulphides

    NASA Astrophysics Data System (ADS)

    Hara, Yotamu Stephen Rainford

    2014-01-01

    Mineral sulphide (MS)-lime (CaO) ion exchange reactions (MS + CaO = MO + CaS) and the effect of CaO/C mole ratio during carbothermic reduction (MS + CaO + C = M + CaS + CO(g)) were investigated for complex froth flotation mineral sulphide concentrates. Phases in the partially and fully reacted samples were characterised by X-ray diffraction (XRD) and scanning electron microscopy (SEM). The primary phases during mineral sulphide-lime ion exchange reactions are Fe3O4, CaSO4 Cu2S, and CaS. A complex liquid phase of Ca2CuFeO3S forms during mineral sulphide-lime exchange reactions above 1173 K. The formation mechanisms of Ca2CuFeO3S liquid phase are determined by characterising the partially reacted samples. The reduction rate and extent of mineral sulphides in the presence of CaO and C increase with the increase in CaO/C ratio. The metallic phases are surrounded by the CaS rich phase at CaO/C > 1, but the metallic phases and CaS are found as separate phases at CaO/C < 1. Experimental results show that the stoichiometric ratio of carbon should be slightly higher than that of CaO. The reactions between CaO and gangue minerals (SiO2 and Al2O3) are only observed at CaO/C > 1 and the reacted samples are excessively sintered.

  19. The global impact of mineral dust on cloud droplet number concentration

    NASA Astrophysics Data System (ADS)

    Karydis, V.; Tsimpidi, A.; Bacer, S.; Pozzer, A.; Nenes, A.; Lelieveld, J.

    2016-12-01

    This study assesses the importance of mineral dust for cloud droplet formation by taking into account i) the adsorption of water on the surface of insoluble dust particles, ii) the coating of soluble material on the surface of mineral particles which augments their cloud condensation nuclei activity, and iii) the effect of dust on the inorganic aerosol concentrations through thermodynamic interactions with mineral cations. Simulations are carried out with the EMAC chemistry climate model that calculates the global atmospheric aerosol composition using the ISORROPIA-II thermodynamic equilibrium model and considers the gas phase interactions with K+-Ca2+-Mg2+-NH4+-Na+-SO42-NO3-Cl-H2O particle components. Emissions of the inert mineral dust and the reactive dust aerosol components are calculated online by taking into account the soil particle size distribution and chemical composition of different deserts worldwide (Karydis et al., 2016). We have implemented the "unified dust activation parameterization" (Kumar et al., 2011; Karydis et al., 2011) to calculate the droplet number concentration by taking into account the inherent hydrophilicity from adsorption and the acquired hygroscopicity from soluble salts by dust particles. Our simulations suggest that mineral dust significantly increases the cloud droplet number concentration (CDNC) over the main deserts and the adjacent oceans. However, over polluted areas the CDNC decreases significantly in the presence of dust. Furthermore, we investigate the role of adsorption activation of insoluble aerosols and the mineral dust thermodynamic interactions with inorganic anions on the cloud droplet formation. The CDNC sensitivity to the emission load, chemical composition, and inherent hydrophilicity of mineral dust is also tested. ReferencesKarydis, et al. (2011). "On the effect of dust particles on global cloud condensation nuclei and cloud droplet number." J. Geophys. Res. Atmos. 116. Karydis, et al. (2016). "Effects of

  20. Craters of the Moon National Monument as a Terrestrial Mars Analog: Examination of Mars Analog Phosphate Minerals, Phosphate Mineral Shock-Recovery Experiments, and Phosphate Minerals in Martian Meteorites

    NASA Astrophysics Data System (ADS)

    Adcock, C. T.; Hausrath, E.; Tschauner, O. D.; Udry, A.

    2015-12-01

    Martian analogs, meteorites, and data from unmanned missions have greatly advanced our understanding of martian surface and near-surface processes. In particular, terrestrial analogs allow us to investigate Mars-relevant geomorphic, geochemical, petrogenetic, and hydrologic processes, as well as potential habitability. Craters of the Moon National Monument (COTM), located on the Snake River Plain of Idaho in the United States, represents a valuable phosphate-rich Mars analog, allowing us to examine phosphate minerals, important as volatile indicators and potential nutrient providers, under Mars-relevant conditions. COTM is in an arid to semi-arid environment with sub-freezing lows much of the year. Though wetter than present day Mars (24 - 38 cm MAP) [1], COTM may be analogous to a warmer and wetter past Mars. The area is also the locale of numerous lava flows, a number of which have been dated (2,000 to >18,000 y.b.p.) [2]. The flows have experienced weathering over time and thus represent a chronosequence with application to weathering on Mars. The flows have unusual chemistries, including high average phosphate contents (P2O5 1.75 wt% n=23 flows) [2], close to those in rocks analyzed at Gusev Crater, Mars (P2O5 1.79 wt% n=18 rocks) [3]. The Mars-like high phosphorus contents indicate a potential petrogenetic link and are also of astrobiological interest. Further, current samples of Mars phosphate minerals are limited to meteorites which have been heavily shocked - COTM represents a potential pre-shock and geochemical analog to Mars. We investigated weathering on COTM basalts and shock effects on Mars-relevant phosphate minerals. We used scanning electron microscopy, backscattered electron imagery, and X-Ray analysis/mapping to investigate COTM thin sections. Synchrotron diffraction was used to investigate martian meteorites and laboratory shocked Mars/COTM-relevant minerals for comparison. Results of our investigations indicate porosity development correlates

  1. The EPQ Code System for Simulating the Thermal Response of Plasma-Facing Components to High-Energy Electron Impact

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Ward, Robert Cameron; Steiner, Don

    2004-06-15

    The generation of runaway electrons during a thermal plasma disruption is a concern for the safe and economical operation of a tokamak power system. Runaway electrons have high energy, 10 to 300 MeV, and may potentially cause extensive damage to plasma-facing components (PFCs) through large temperature increases, melting of metallic components, surface erosion, and possible burnout of coolant tubes. The EPQ code system was developed to simulate the thermal response of PFCs to a runaway electron impact. The EPQ code system consists of several parts: UNIX scripts that control the operation of an electron-photon Monte Carlo code to calculate themore » interaction of the runaway electrons with the plasma-facing materials; a finite difference code to calculate the thermal response, melting, and surface erosion of the materials; a code to process, scale, transform, and convert the electron Monte Carlo data to volumetric heating rates for use in the thermal code; and several minor and auxiliary codes for the manipulation and postprocessing of the data. The electron-photon Monte Carlo code used was Electron-Gamma-Shower (EGS), developed and maintained by the National Research Center of Canada. The Quick-Therm-Two-Dimensional-Nonlinear (QTTN) thermal code solves the two-dimensional cylindrical modified heat conduction equation using the Quickest third-order accurate and stable explicit finite difference method and is capable of tracking melting or surface erosion. The EPQ code system is validated using a series of analytical solutions and simulations of experiments. The verification of the QTTN thermal code with analytical solutions shows that the code with the Quickest method is better than 99.9% accurate. The benchmarking of the EPQ code system and QTTN versus experiments showed that QTTN's erosion tracking method is accurate within 30% and that EPQ is able to predict the occurrence of melting within the proper time constraints. QTTN and EPQ are verified and validated

  2. The structure of ion-acoustic waves in a low-frequency three-component electron-ion space plasma with two-electron populations

    NASA Astrophysics Data System (ADS)

    Govender, G.; Moolla, S.

    2018-07-01

    Low-frequency ion-acoustic waves are analysed on the ion time-scale, in a three-component electron-ion space plasma. The solitary waves propagate in the positive x direction relative to an ambient magnetic field ěc {B}_0 which forms static background for a configuration consisting of cool fluid ions and both warm and hot Boltzmann-distributed electrons with temperatures T_{ic}, T_{ew} and T_{eh}, respectively. We derive linear dispersion relation for the waves by introducing first-order density, pressure and velocity perturbations into the ion fluid equations. Additionally, the variation in the nonlinear structure of the waves are investigated by carrying out a full parametric analysis utilising our numerical code. Our results reveal that ion-acoustic waves exhibit well-defined nonlinear spikes at speeds of M≥ 2.25 and an electric field amplitude of E_0=0.85. It is also shown that low wave speeds (M≤ 2), higher densities of the hot electrons, antiparallel drifting of the cool fluid ions, and increased ion temperatures all lead to significant dispersive effects. The ion-acoustic plasma waves featured in this paper have forms that are consistent with those classified as the type-A and type-B broadband electrostatic noise (BEN) observed in the data obtained from earlier satellite missions.

  3. Bioreduction of Fe-bearing clay minerals and their reactivity toward pertechnetate (Tc-99)

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Bishop, Michael E.; Dong, Hailiang; Kukkadapu, Ravi K.

    2011-07-01

    99Technetium (99Tc) is a fission product of uranium-235 and plutonium-239 and poses a high environmental hazard due to its long half-life (t1/2 = 2.13 x 105 y), abundance in nuclear wastes, and environmental mobility under oxidizing conditions [i.e., Tc(VII)]. Under reducing conditions, Tc(VII) can be reduced to insoluble Tc(IV). Ferrous iron [Fe(II)], either in aqueous form or in mineral form, has been used to reduce Tc(VII) to Tc(IV). However, the reactivity of Fe(II) from clay minerals, other than nontronite, toward immobilization of Tc(VII) and its role in retention of reduced Tc(IV) have not been investigated. In this study the reactivitymore » of a suite of clay minerals toward Tc(VII) reduction and immobilization was evaluated. The clay minerals chosen for this study included five members in the smectite-illite (S-I) series, (montmorillonite, nontronite, rectorite, mixed layered I-S, and illite), chlorite, and palygorskite. Fe-oxides were removed from these minerals with a modified dithionite-citrate-bicarbonate (DCB) procedure. The total Fe content of these clay minerals, after Fe-oxide removal, ranged from 0.7 to 30.4% by weight, and the Fe(III)/Fe(total) ratio ranged from 44.9 to 98.5%. X-ray diffraction (XRD) and Mössbauer spectroscopy results showed that after Fe oxide removal the clay minerals were free of Fe-oxides. Scanning electron microscopy (SEM) revealed that little dissolution occurred during the DCB treatment. Bioreduction experiments were performed in bicarbonate buffer (pH-7) with Fe(III) in the clay minerals as the sole electron acceptor, lactate as the sole electron donor, and Shewanella Putrifaciens CN32 cells as mediators. In select tubes, anthraquinone-2,6-disulfate (AQDS) was added as electron shuttle to facilitate electron transfer. The extent of Fe(III) bioreduction was the highest for chlorite (~43 wt%) and the lowest for palygorskite (~4.17 wt%). In the S-I series, NAu-2 was the most reducible (~31 %) and illite the least (~0

  4. 30 CFR 7.508 - Harmful gas removal components.

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... chemical used for removal of harmful gas shall be— (1) Contained such that when stored or used it cannot... for disposal of used chemical. (c) Each harmful gas removal component shall be tested to determine its... 30 Mineral Resources 1 2012-07-01 2012-07-01 false Harmful gas removal components. 7.508 Section 7...

  5. 30 CFR 7.508 - Harmful gas removal components.

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... chemical used for removal of harmful gas shall be— (1) Contained such that when stored or used it cannot... for disposal of used chemical. (c) Each harmful gas removal component shall be tested to determine its... 30 Mineral Resources 1 2013-07-01 2013-07-01 false Harmful gas removal components. 7.508 Section 7...

  6. 30 CFR 7.508 - Harmful gas removal components.

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... chemical used for removal of harmful gas shall be— (1) Contained such that when stored or used it cannot... for disposal of used chemical. (c) Each harmful gas removal component shall be tested to determine its... 30 Mineral Resources 1 2014-07-01 2014-07-01 false Harmful gas removal components. 7.508 Section 7...

  7. Application of electron probe X-ray microanalysis to calcification studies of bone and cartilage.

    PubMed

    Landis, W J

    1979-01-01

    The use of electron probe x-ray microanalysis in previous studies of bone and cartilage has been reviewed with emphasis on the results which have contributed to some of the current concepts of the mechanism of mineralization in these tissues. A number of investigations continuing in the author's laboratory utilizing high spatial resolution x-ray microanalysis and anhydrous methods of specimen preparation are described, including aspects concerning the derivation of calibration curves from synthetic calcium phosphate solids, qualitative and quantitative analyses of calcium and phosphorus in bone from embryonic chicks and in growth plate cartilage from rats, and the role of organically-bound phosphorus in mineralizing tissues. The data obtained have helped identify brushite, CaHPO4-2H2O, as the major crystalline solid phase of calcium phosphate in the earliest mineral deposits of bone tissue, brushite and poorly crystalline hydroxyapatite in bone mineral of increasing age, and poorly crystalline hydroxyapatite in the most mature mineral portions of the tissue. Growth plate cartilage examination has revealed calcium and phosphorus in single mitochondrial granules within chondrocytes and in certain extracellular particles distinct from matrix vesicles. These results have provided important information about the possible roles of cells, extracellular components, and the organic matrix in the regulation of mineralization and about the composition, structure, and organization of the mineral phase as a function of progressively increasing age and maturation of the tissues studied.

  8. Short-Range-Order Mineral Physical Protection On Black Carbon Stabilization

    NASA Astrophysics Data System (ADS)

    Liang, B.; Weng, Y. T.; Wang, C. C.; Song, Y. F.; Lehmann, J.; Wang, C. H.

    2015-12-01

    Soil organic matter is one of the largest reservoirs in global carbon cycle, and black carbon (BC) represents a chemical resistant component. Black C plays an important role in global climate change. Generally considered recalcitrant due to high aromaticity, the reactive surface and functional groups of BC are crucial for carbon sequestration in soils. Mineral sorption and physical protection is an important mechanism for BC long term stabilization and sequestration in environments. Previous studies on mineral protection of BC were limited to analysis techniques in two-dimensions, for example, by SEM, TEM, and NanoSIMS. Little is known about the scope of organo-mineral association, the in-situ distribution and forms of minerals, and the ultimate interplay of BC and minerals. The aim of this study is to investigate the three-dimensional interaction of organic C and minerals in submicron scale using synchrotron-based Transmission X-ray Microcopy (TXM) and Fourier-Transform Infrared Spectroscopy (FTIR). Abundant poorly-crystallined nano-minerals particles were observed. These short-range-order (SRO) minerals also aggregate into clusters and sheets, and form envelops-like structures on the surface of BC. On top of large surface contact area, the intimate interplay between BC and minerals reinforces the stability of both organic C and minerals, resulting from chemical bonding through cation bridging and ligand exchange. The mineral protection enhances BC stabilization and sequestration and lowers its bioavailability in environment. The results suggest that mineral physical protection for BC sequestration may be more important than previous understanding.

  9. Detection of the high energy component of Jovian electrons at 1 AU with the PAMELA experiment.

    NASA Astrophysics Data System (ADS)

    Casolino, M.; PAMELA Collaboration

    PAMELA is a satellite-borne experiment that will be launched in the first half of 2006 It will make long duration measurements of cosmic radiation over an extended energy range 80Mev to 200 GeV Specifically PAMELA will measure the cosmic-ray antiproton and positron spectra over the largest energy range ever achieved 80MeV - 190 GeV and will search for antinuclei with unprecedented sensitivity Furthermore it will measure the light nuclear component of cosmic rays and investigate phenomena connected with solar and earth physics The apparatus consists of a time of flight system a magnetic spectrometer an electromagnetic imaging calorimeter a shower tail catcher scintillator a neutron detector and an anticoincidence system The Jovian magnetosphere is a powerful accelerator of electrons to several tens of MeV as observed at first by Pioneer 10 spacecraft 1973 The propagation of Jovian electrons to Earth is affected by modulation due to Corotating Interaction Regions CIR Their flux at Earth is moreover modulated because every 13 months Earth and Jupiter are aligned along the average direction of the Parker spiral of the Interplanetary Magnetic Field For its characteristics PAMELA will be able to measure the high energy tail of the Jovian electrons in the energy range from 50 MeV up to 130 MeV With long term observation it will also be possible to detect the Jovian component reaccelated at the solar wind termination shock from the galactic flux

  10. Electron microscopy and forensic practice

    NASA Astrophysics Data System (ADS)

    Kotrlý, Marek; Turková, Ivana

    2013-05-01

    Electron microanalysis in forensic practice ranks among basic applications used in investigation of traces (latents, stains, etc.) from crime scenes. Applying electron microscope allows for rapid screening and receiving initial information for a wide range of traces. SEM with EDS/WDS makes it possible to observe topography surface and morphology samples and examination of chemical components. Physical laboratory of the Institute of Criminalistics Prague use SEM especially for examination of inorganic samples, rarely for biology and other material. Recently, possibilities of electron microscopy have been extended considerably using dual systems with focused ion beam. These systems are applied mainly in study of inner micro and nanoparticles , thin layers (intersecting lines in graphical forensic examinations, analysis of layers of functional glass, etc.), study of alloys microdefects, creating 3D particles and aggregates models, etc. Automated mineralogical analyses are a great asset to analysis of mineral phases, particularly soils, similarly it holds for cathode luminescence, predominantly colour one and precise quantitative measurement of their spectral characteristics. Among latest innovations that are becoming to appear also at ordinary laboratories are TOF - SIMS systems and micro Raman spectroscopy with a resolution comparable to EDS/WDS analysis (capable of achieving similar level as through EDS/WDS analysis).

  11. Impact of mineralization on carbon dioxide migration in term of critical value of fault permeability.

    NASA Astrophysics Data System (ADS)

    Alshammari, A.; Brantley, D.; Knapp, C. C.; Lakshmi, V.

    2017-12-01

    In this study, multi chemical components ((H2O, H2S) will be injected with supercritical carbon dioxide in onshore part of South Georgia Rift (SGR) Basin model. Chemical reaction expected issue between these components to produce stable mineral of carbonite rocks by the time. The 3D geological model has been extracted from petrel software and computer modelling group (CMG) package software has been used to build simulation model explain the effect of mineralization on fault permeability that control on plume migration critically between (0-0.05 m Darcy). The expected results will be correlated with single component case (CO2 only) to evaluate the importance the mineralization on CO2 plume migration in structure and stratigraphic traps and detect the variation of fault leakage in case of critical values (low permeability). The results will also, show us the ratio of every trapped phase in (SGR) basin reservoir model.

  12. Importance of interlayer H bonding structure to the stability of layered minerals

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Conroy, Michele; Soltis, Jennifer A.; Wittman, Rick S.

    Layered (oxy) hydroxide minerals often possess out-of-plane hydrogen atoms that form hydrogen bonding networks which stabilize the layered structure. However, less is known about how the ordering of these bonds affects the structural stability and solubility of these minerals. Here, we report a new strategy that uses the focused electron beam to probe the effect of differences in hydrogen bonding networks on mineral solubility. In this regard, the dissolution behavior of boehmite (γ-AlOOH) and gibbsite (γ-Al(OH)3) were compared and contrasted in real time via liquid cell electron microscopy. Under identical such conditions, 2D-nanosheets of boehmite (γ-AlOOH) exfoliated from the bulkmore » and then rapidly dissolved, whereas gibbsite was stable. Further, substitution of only 1% Fe(III) for Al(III) in the structure of boehmite inhibited delamination and dissolution. Factors such as pH, radiolytic species, and knock on damage were systematically studied and eliminated as proximal causes for boehmite dissolution. Instead, the creation of electron/hole pairs was considered to be the mechanism that drove dissolution. The widely disparate behaviors of boehmite, gibbsite, and Fe-doped boehmite are discussed in the context of differences in the OH bond strengths, hydrogen bonding networks, and the presence or absence of electron/hole recombination centers.« less

  13. Importance of interlayer H bonding structure to the stability of layered minerals

    DOE PAGES

    Conroy, Michele; Soltis, Jennifer A.; Wittman, Rick S.; ...

    2017-10-16

    Layered (oxy) hydroxide minerals often possess out-of-plane hydrogen atoms that form hydrogen bonding networks which stabilize the layered structure. However, less is known about how the ordering of these bonds affects the structural stability and solubility of these minerals. Here, we report a new strategy that uses the focused electron beam to probe the effect of differences in hydrogen bonding networks on mineral solubility. In this regard, the dissolution behavior of boehmite (γ-AlOOH) and gibbsite (γ-Al(OH)3) were compared and contrasted in real time via liquid cell electron microscopy. Under identical such conditions, 2D-nanosheets of boehmite (γ-AlOOH) exfoliated from the bulkmore » and then rapidly dissolved, whereas gibbsite was stable. Further, substitution of only 1% Fe(III) for Al(III) in the structure of boehmite inhibited delamination and dissolution. Factors such as pH, radiolytic species, and knock on damage were systematically studied and eliminated as proximal causes for boehmite dissolution. Instead, the creation of electron/hole pairs was considered to be the mechanism that drove dissolution. The widely disparate behaviors of boehmite, gibbsite, and Fe-doped boehmite are discussed in the context of differences in the OH bond strengths, hydrogen bonding networks, and the presence or absence of electron/hole recombination centers.« less

  14. Spatial variation in microbial processes controlling carbon mineralization within soils and sediments

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Fendorf, Scott; Kleber, Markus; Nico, Peter

    Soils have a defining role in global carbon cycling, having one of the largest dynamic stocks of C on earth—3300 Pg of C are stored in soils, which is three-times the amount stored in the atmosphere and more than the terrestrial land plants. An important control on soil organic matter (SOM) quantities is the mineralization rate. It is well recognized that the rate and extent of SOM mineralization is affected by climatic factors and mineral-organic matter associations. What remained elusive is to what extent constraints on microbial metabolism induced by the respiratory pathway, and specifically the electron acceptor in respiration,more » control overall rates of carbon mineralization in soils. Therefore, physical factors limiting oxygen diffusion such as soil texture and aggregate size (soil structure) may therefore be central controls on C mineralization rates. The goal of our research was therefore to determine if variations in microbial metabolic rates induced by anaerobic microsites in soils are a major control on SOM mineralization rates and thus storage. We performed a combination of laboratory experiments and field investigations will be performed to fulfill our research objectives. We used laboratory studies to examine fundamental factors of respiratory constraints (i.e., electron acceptor) on organic matter mineralization rates. We ground our laboratory studies with both manipulation of field samples and in-field measurements. Selection of the field sites is guided by variation in soil texture and structure while having (other environmental/soil factors constant. Our laboratory studies defined redox gradients and variations in microbial metabolism operating at the aggregate-scale (cm-scale) within soils using a novel constructed diffusion reactor. We further examined micro-scale variation in terminal electron accepting processes and resulting C mineralization rates within re-packed soils. A major outcome of our research is the ability to quantitatively

  15. Geophysical technique for mineral exploration and discrimination based on electromagnetic methods and associated systems

    DOEpatents

    Zhdanov,; Michael, S [Salt Lake City, UT

    2008-01-29

    Mineral exploration needs a reliable method to distinguish between uneconomic mineral deposits and economic mineralization. A method and system includes a geophysical technique for subsurface material characterization, mineral exploration and mineral discrimination. The technique introduced in this invention detects induced polarization effects in electromagnetic data and uses remote geophysical observations to determine the parameters of an effective conductivity relaxation model using a composite analytical multi-phase model of the rock formations. The conductivity relaxation model and analytical model can be used to determine parameters related by analytical expressions to the physical characteristics of the microstructure of the rocks and minerals. These parameters are ultimately used for the discrimination of different components in underground formations, and in this way provide an ability to distinguish between uneconomic mineral deposits and zones of economic mineralization using geophysical remote sensing technology.

  16. 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 Wilderness...

  17. 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 Wilderness...

  18. 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 Wilderness...

  19. 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 Wilderness...

  20. 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 Wilderness...

  1. [Study of Determination of Oil Mixture Components Content Based on Quasi-Monte Carlo Method].

    PubMed

    Wang, Yu-tian; Xu, Jing; Liu, Xiao-fei; Chen, Meng-han; Wang, Shi-tao

    2015-05-01

    Gasoline, kerosene, diesel is processed by crude oil with different distillation range. The boiling range of gasoline is 35 ~205 °C. The boiling range of kerosene is 140~250 °C. And the boiling range of diesel is 180~370 °C. At the same time, the carbon chain length of differentmineral oil is different. The carbon chain-length of gasoline is within the scope of C7 to C11. The carbon chain length of kerosene is within the scope of C12 to C15. And the carbon chain length of diesel is within the scope of C15 to C18. The recognition and quantitative measurement of three kinds of mineral oil is based on different fluorescence spectrum formed in their different carbon number distribution characteristics. Mineral oil pollution occurs frequently, so monitoring mineral oil content in the ocean is very important. A new method of components content determination of spectra overlapping mineral oil mixture is proposed, with calculation of characteristic peak power integrationof three-dimensional fluorescence spectrum by using Quasi-Monte Carlo Method, combined with optimal algorithm solving optimum number of characteristic peak and range of integral region, solving nonlinear equations by using BFGS(a rank to two update method named after its inventor surname first letter, Boyden, Fletcher, Goldfarb and Shanno) method. Peak power accumulation of determined points in selected area is sensitive to small changes of fluorescence spectral line, so the measurement of small changes of component content is sensitive. At the same time, compared with the single point measurement, measurement sensitivity is improved by the decrease influence of random error due to the selection of points. Three-dimensional fluorescence spectra and fluorescence contour spectra of single mineral oil and the mixture are measured by taking kerosene, diesel and gasoline as research objects, with a single mineral oil regarded whole, not considered each mineral oil components. Six characteristic peaks are

  2. Identification of concrete deteriorating minerals by polarizing and scanning electron microscopy

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Gregerova, Miroslava, E-mail: mirka@sci.muni.cz; Vsiansky, Dalibor, E-mail: daliborv@centrum.cz

    2009-07-15

    The deterioration of concrete represents one of the most serious problems of civil engineering worldwide. Besides other processes, deterioration of concrete consists of sulfate attack and carbonation. Sulfate attack results in the formation of gypsum, ettringite and thaumasite in hardened concrete. Products of sulfate attack may cause a loss of material strength and a risk of collapse of the concrete constructions. The authors focused especially on the microscopical research of sulfate attack. Concrete samples were taken from the Charles Bridge in Prague, Czech Republic. A succession of degrading mineral formation was suggested. Microscope methods represent a new approach to solvingmore » the deterioration problems. They enable evaluation of the state of concrete constructions and in cooperation with hydro-geochemistry, mathematics and statistics permit prediction of the durability of a structure. Considering the number of concrete constructions and their age, research of concrete deterioration has an increasing importance. The results obtained can also be useful for future construction, because they identify the risk factors associated with formation of minerals known to degrade structures.« less

  3. Mineral deposit densities for estimating mineral resources

    USGS Publications Warehouse

    Singer, Donald A.

    2008-01-01

    Estimates of numbers of mineral deposits are fundamental to assessing undiscovered mineral resources. Just as frequencies of grades and tonnages of well-explored deposits can be used to represent the grades and tonnages of undiscovered deposits, the density of deposits (deposits/area) in well-explored control areas can serve to represent the number of deposits. Empirical evidence presented here indicates that the processes affecting the number and quantity of resources in geological settings are very general across many types of mineral deposits. For podiform chromite, porphyry copper, and volcanogenic massive sulfide deposit types, the size of tract that geologically could contain the deposits is an excellent predictor of the total number of deposits. The number of mineral deposits is also proportional to the type’s size. The total amount of mineralized rock is also proportional to size of the permissive area and the median deposit type’s size. Regressions using these variables provide a means to estimate the density of deposits and the total amount of mineralization. These powerful estimators are based on analysis of ten different types of mineral deposits (Climax Mo, Cuban Mn, Cyprus massive sulfide, Franciscan Mn, kuroko massive sulfide, low-sulfide quartz-Au vein, placer Au, podiform Cr, porphyry Cu, and W vein) from 108 permissive control tracts around the world therefore generalizing across deposit types. Despite the diverse and complex geological settings of deposit types studied here, the relationships observed indicate universal controls on the accumulation and preservation of mineral resources that operate across all scales. The strength of the relationships (R 2=0.91 for density and 0.95 for mineralized rock) argues for their broad use. Deposit densities can now be used to provide a guideline for expert judgment or used directly for estimating the number of most kinds of mineral deposits.

  4. Reduction And Immobilization Of Hexavalent Chromium By Microbially Reduced Fe-bearing Clay Minerals

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Bishop, Michael E.; Glasser, Paul; Dong, Hailiang

    Hexavalent chromium (Cr6+) is a major contaminant in the environment. As a redox-sensitive element, the fate and toxicity of chromium is controlled by reduction-oxidation (redox) reactions. Previous research has shown the ability of structural Fe(II) in naturally present and chemically reduced clay minerals to reduce Cr6+ to Cr(III) as a way of immobilization and detoxification. However, it is still poorly known whether or not structural Fe(II) in biologically reduced clay minerals exhibits a similar reactivity and if so, what the kinetics and mechanisms of Cr6+ reduction are. The objective of this study was to determine the kinetics and possible mechanismsmore » of Cr6+ reduction by structural Fe(II) in microbially reduced clay minerals and the nature of reduced Cr(III). Structural Fe(III) in nontronite (NAu-2), montmorillonite (SWy-2), chlorite (CCa-2), and clay-rich sediments from the Ringold Formation of the Hanford site of Washington State, USA was first bioreduced to Fe(II) by an iron-reducing bacterium Geobacter sulfurreducens with acetate as the sole electron donor and anthraquinone-2,6-disulfate (AQDS) as electron shuttle in synthetic groundwater (pH 7). Biogenic Fe(II) was then used to reduce aqueous Cr6+ at three different temperatures, 10°, 20°, and 30°C, in order to determine the temperature dependence of the redox reaction between Cr6+ and clay-Fe(II). The results showed that nontronite and montmorillonite were most effective in reducing aqueous Cr6+ at all three temperatures. In contrast, most Fe(II) in chlorite was not reactive towards Cr6+ reduction at 10°C, though at 30°C there was some reduction. For all the clay minerals, the ratio of total Fe(II) oxidized to Cr6+ reduced was close to the expected stoichiometric value of 3. Characterization of the Cr-clay reaction product with scanning electron microscopy with focused ion beam and transmission electron microscopy with electron energy loss spectroscopy revealed that reduced chromium was

  5. Natural mineral bottled waters available on the Polish market as a source of minerals for the consumers. Part 1. Calcium and magnesium.

    PubMed

    Gątarska, Anna; Tońska, Elżbieta; Ciborska, Joanna

    2016-01-01

    Natural mineral waters may be an essential source of calcium, magnesium and other minerals. In bottled waters, minerals occur in an ionized form which is very well digestible. However, the concentration of minerals in underground waters (which constitute the material for the production of bottled waters) varies. In view of the above, the type of water consumed is essential. The aim of the study was to estimate the calcium and magnesium contents in products available on the market and to evaluate calcium and magnesium consumption with natural mineral water by different consumer groups with an assumed volume of the consumed product. These represented forty different brands of natural mineral available waters on Polish market. These waters were produced in Poland or other European countries. Among the studied products, about 30% of the waters were imported from Lithuania, Latvia, Czech Republic, France, Italy and Germany. The content of calcium and magnesium in mineral waters was determined using flame atomic absorption spectrometry in an acetylene-air flame. Further determinations were carried out using atomic absorption spectrometer--ICE 3000 SERIES-THERMO-England, equipped with a GLITE data station, background correction (a deuterium lamp) as well as other cathode lamps. Over half of the analysed natural mineral waters were medium-mineralized. The natural mineral waters available on the market can be characterized by a varied content of calcium and magnesium and a high degree of product mineralization does not guarantee significant amounts of these components. Among the natural mineral waters available on the market, only a few feature the optimum calcium-magnesium proportion (2:1). Considering the mineralization degree of the studied products, it can be stated that the largest percentage of products with significant calcium and magnesium contents can be found in the high-mineralized water group. For some natural mineral waters, the consumption of 1 litre daily may

  6. Importance of interlayer H bonding structure to the stability of layered minerals

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Conroy, Michele; Soltis, Jennifer A.; Wittman, Rick S.

    2017-10-16

    The exact atomic structures of layered minerals have been difficult to characterize because the layers often possess out-of-plane hydrogen atoms that cannot be detected by many analytical techniques. However, the ordering of these bonds are thought to play a fundamental role in the structural stability and solubility of layered minerals. We report a new strategy of using the intense radiation field of a focused electron beam to probe the effect of differences in hydrogen bonding networks on mineral solubility while simultaneously imaging the dissolution behavior in real time via liquid cell electron microscopy. We show the loss in hydrogens frommore » interlayers of boehmite (γ-AlOOH) resulted in 2D nanosheets exfoliating from the bulk that subsequently and rapidly dissolved. However gibbsite (γ-Al(OH)3), with its higher concentration of OH terminating groups, was more accommodating to the deprotonation and stable under the beam.« less

  7. Hierarchy effect on electronic structure and core-to-valence transitions in bone tissue: perspectives in medical nanodiagnostics of mineralized bone

    NASA Astrophysics Data System (ADS)

    Samoilenko, Dmitrii O.; Avrunin, Alexander S.; Pavlychev, Andrey A.

    2017-06-01

    Electronic structure and core-to-valence transitions in bone tissue are examined in the framework of the morphological 3DSL model that takes into account (i) structural and functional organization of the skeleton in the normal and pathological conditions and (ii) peculiarities of electron wave propagation in a three-dimensional superlattice of "black-nanocrystallites-in-muddy-waters". Our focus is on the HAP-to-bone red shifts of core-to-valence transitions near Ca and P 2p and O 1s edges in single-crystal hydroxyapatite (HAP) Ca10(PO4)6(OH)2. The origin of the HAP-to-bone shift is discussed and the extended comparative analysis of the experimental data is performed. The detected spectral shift is assigned with the effect of hierarchical organization of bone tissue. This hierarchy effect on the core-to-valence transition energies is regarded as a promising tool for medical imaging and perspective pathway for nanodiagnostics of mineralized bone. Contribution to the Topical Issue "Dynamics of Systems at the Nanoscale", edited by Andrey Solov'yov and Andrei Korol.

  8. Components of polarization-transfer to a bound proton in a deuteron measured by quasi-elastic electron scattering

    NASA Astrophysics Data System (ADS)

    Izraeli, D.; Yaron, I.; Schlimme, B. S.; Achenbach, P.; Arenhövel, H.; Ashkenazi, A.; Beričič, J.; Böhm, R.; Bosnar, D.; Cohen, E. O.; Distler, M. O.; Esser, A.; Friščić, I.; Gilman, R.; Korover, I.; Lichtenstadt, J.; Mardor, I.; Merkel, H.; Middleton, D. G.; Mihovilovič, M.; Müller, U.; Olivenboim, M.; Piasetzky, E.; Pochodzalla, J.; Ron, G.; Schoth, M.; Schulz, F.; Sfienti, C.; Širca, S.; Štajner, S.; Strauch, S.; Thiel, M.; Tyukin, A.; Weber, A.; A1 Collaboration

    2018-06-01

    We report the first measurements of the transverse (Px and Py) and longitudinal (Pz) components of the polarization transfer to a bound proton in the deuteron via the 2H (e → ,e‧ p →) reaction, over a wide range of missing momentum. A precise determination of the electron beam polarization reduces the systematic uncertainties on the individual components to a level that enables a detailed comparison to a state-of-the-art calculation of the deuteron using free-proton electromagnetic form factors. We observe very good agreement between the measured and the calculated Px /Pz ratios, but deviations of the individual components. Our results cannot be explained by medium modified electromagnetic form factors. They point to an incomplete description of the nuclear reaction mechanism in the calculation.

  9. Surface materials map of Afghanistan: iron-bearing minerals and other materials

    USGS Publications Warehouse

    King, Trude V.V.; Kokaly, Raymond F.; Hoefen, Todd M.; Dudek, Kathleen B.; Livo, Keith E.

    2012-01-01

    This map shows the distribution of selected iron-bearing minerals and other materials derived from analysis of HyMap imaging spectrometer data of Afghanistan. Using a NASA (National Aeronautics and Space Administration) WB-57 aircraft flown at an altitude of ~15,240 meters or ~50,000 feet, 218 flight lines of data were collected over Afghanistan between August 22 and October 2, 2007. The HyMap data were converted to apparent surface reflectance, then further empirically adjusted using ground-based reflectance measurements. The reflectance spectrum of each pixel of HyMap data was compared to the spectral features of reference entries in a spectral library of minerals, vegetation, water, ice, and snow. This map shows the spatial distribution of iron-bearing minerals and other materials having diagnostic absorptions at visible and near-infrared wavelengths. These absorptions result from electronic processes in the minerals. Several criteria, including (1) the reliability of detection and discrimination of minerals using the HyMap spectrometer data, (2) the relative abundance of minerals, and (3) the importance of particular minerals to studies of Afghanistan's natural resources, guided the selection of entries in the reference spectral library and, therefore, guided the selection of mineral classes shown on this map. Minerals occurring abundantly at the surface and those having unique spectral features were easily detected and discriminated. Minerals having similar spectral features were less easily discriminated, especially where the minerals were not particularly abundant and (or) where vegetation cover reduced the absorption strength of mineral features. Complications in reflectance calibration also affected the detection and identification of minerals.

  10. 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.

  11. Ceramic component for electrodes

    DOEpatents

    Marchant, David D.

    1979-01-01

    A ceramic component suitable for preparing MHD generator electrodes consists of HfO.sub.2 and sufficient Tb.sub.4 O.sub.7 to stabilize at least 60 volume percent of the HfO.sub.2 into the cubic structure. The ceramic component may also contain a small amount of PrO.sub.2, Yb.sub.2 O.sub.3 or a mixture of both to improve stability and electronic conductivity of the electrode. The component is highly resistant to corrosion by molten potassium seed and molten coal slag in the MHD fluid and exhibits both ionic and electronic conductivity.

  12. Connective Tissue Mineralization in Abcc6−/− Mice, a Model for Pseudoxanthoma Elasticum

    PubMed Central

    Kavukcuoglu, N. Beril; Li, Qiaoli; Pleshko, Nancy; Uitto, Jouni

    2012-01-01

    Pseudoxanthoma elasticum (PXE) is a heritable multisystem disorder characterized by ectopic mineralization. However, the structure of the mineral deposits, their interactions with the connective tissue matrix, and the details of the progressive maturation of the mineral crystals are currently unknown. In this study, we examined the mineralization processes in Abcc6−/− mice, a model system for PXE, by energy dispersive X-ray, and Fourier transform infrared imaging spectroscopy (FT-IRIS). The results indicated that the principal components of the mineral deposits were calcium and phosphate which co-localized within the histologically demonstrable lesions determined by topographic mapping. The Ca/P ratio increased in samples with progressive mineralization reaching the value comparable to that in endochondral bone. A progressive increase in mineralization was also reflected by increased mineral-to-matrix ratio determined by FT-IRIS. Determination of the mineral phases by FT-IRIS suggested progressive maturation of the mineral deposits from amorphous calcium phosphate to hydroxyapatite. These results provide critical information of the mechanisms of mineralization in PXE, with potential pharmacologic implications. PMID:22421595

  13. Carbonate and sulfate minerals in the Chassigny meteorite

    NASA Technical Reports Server (NTRS)

    Wentworth, Susan J.; Gooding, James L.

    1991-01-01

    SO2 and CO2 from pyrolysis and combustion of bulk Chassigny and infrared traces of sulfate and carbonate minerals have been previously reported. Using scanning electron microscopy (SEM) and energy-dispersive x ray spectrometry (EDS), portions of these samples are searched, and a Ca-sulfate/carbonate association is confirmed.

  14. The Origin of Refractory Minerals in Comet 81P/Wild 2

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Chi, M; Ishii, H A; Simon, S B

    2008-11-20

    Refractory Ti-bearing minerals in the calcium-, aluminium-rich inclusion (CAI) Inti, recovered from the comet 81P/Wild 2 sample, were examined using analytical (scanning) transmission electron microscopy (STEM) methods including imaging, nanodiffraction, energy dispersive spectroscopy (EDX) and electron energy loss spectroscopy (EELS). Inti fassaite (Ca(Mg,Ti,Al)(Si,Al){sub 2}O{sub 6}) was found to have a Ti{sup 3+}/Ti{sup 4+} ratio of 2.0 {+-} 0.2, consistent with fassaite in other solar system CAIs. The oxygen fugacity (log f{sub O{sub 2}}) of formation estimated from this ratio, assuming equilibration among phases at 1509K, is -19.4 {+-} 1.3. This value is near the canonical solar nebula value (-18.1 {+-}more » 0.3) and in close agreement with that reported for fassaite-bearing Allende CAIs (-19.8 {+-} 0.9) by other researchers using the same assumptions. Nanocrystals of osbornite (Ti(V)N), 2-40 nm in diameter, are embedded as inclusions within anorthite, spinel and diopside in Inti. Vanadium is heterogeneously distributed within some osbornite crystals. Compositions range from pure TiN to Ti{sub 0.36}V{sub 0.64}N. The possible presence of oxide and carbide in solid solution with the osbornite was evaluated. The osbornite may contain O but does not contain C. The presence of osbornite, likely a refractory early condensate, together with the other refractory minerals in Inti, indicates that the parent comet contains solids that condensed closer to the proto-sun than the distance at which the parent comet itself accreted. The estimated oxygen fugacity and the reported isotopic and chemical compositions are consistent with Inti originating in the inner solar system as opposed to it being a surviving CAI from an extrasolar source. These results provide insight for evaluating the validity of models of radial mass transport dynamics in the early solar system. The oxidation environments inferred for the Inti mineral assemblage are inconsistent with an X

  15. A simplified methylcoenzyme M methylreductase assay with artificial electron donors and different preparations of component C from Methanobacterium thermoautotrophicum delta H.

    PubMed Central

    Hartzell, P L; Escalante-Semerena, J C; Bobik, T A; Wolfe, R S

    1988-01-01

    Different preparations of the methylreductase were tested in a simplified methylcoenzyme M methylreductase assay with artificial electron donors under a nitrogen atmosphere. ATP and Mg2+ stimulated the reaction. Tris(2,2'-bipyridine)ruthenium (II), chromous chloride, chromous acetate, titanium III citrate, 2,8-diaminoacridine, formamidinesulfinic acid, cob(I)alamin (B12s), and dithiothreitol were tested as electron donors; the most effective donor was titanium III citrate. Methylreductase (component C) was prepared by 80% ammonium sulfate precipitation, 70% ammonium sulfate precipitation, phenyl-Sepharose chromatography, Mono Q column chromatography, DEAE-cellulose column chromatography, or tetrahydromethanopterin affinity column chromatography. Methylreductase preparations which were able to catalyze methanogenesis in the simplified reaction mixture contained contaminating proteins. Homogeneous component C obtained from a tetrahydromethanopterin affinity column was not active in the simplified assay but was active in a methylreductase assay that contained additional protein components. Images PMID:3372480

  16. Exploring the biochemistry at the extracellular redox frontier of bacterial mineral Fe(III) respiration

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Richardson, David J.; Edwards, Marcus; White, Gaye F.

    2012-06-01

    Many species of the bacterial Shewanella genus are notable for their ability to respire in anoxic environments utilizing insoluble minerals of Fe(III) and Mn(IV) as extracellular electron acceptors. In Shewanella oneidensis, the process is dependent on the decahaem electron-transport proteins that lie at the extracellular face of the outer membrane where they can contact the insoluble mineral substrates. These extracellular proteins are charged with electrons provided by an inter-membrane electron-transfer pathway that links the extracellular face of the outer membrane with the inner cytoplasmic membrane and thereby intracellular electron sources. In the present paper, we consider the common structural featuresmore » of two of these outermembrane decahaem cytochromes, MtrC and MtrF, and bring this together with biochemical, spectroscopic and voltammetric data to identify common and distinct properties of these prototypical members of different clades of the outer-membrane decahaem cytochrome superfamily.« less

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

    USGS Publications Warehouse

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

    1987-01-01

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

  18. Chemometric analysis of minerals in gluten-free products.

    PubMed

    Gliszczyńska-Świgło, Anna; Klimczak, Inga; Rybicka, Iga

    2018-06-01

    Numerous studies indicate mineral deficiencies in people on a gluten-free (GF) diet. These deficiencies may indicate that GF products are a less valuable source of minerals than gluten-containing products. In the study, the nutritional quality of 50 GF products is discussed taking into account the nutritional requirements for minerals expressed as percentage of recommended daily allowance (%RDA) or percentage of adequate intake (%AI) for a model celiac patient. Elements analyzed were calcium, potassium, magnesium, sodium, copper, iron, manganese, and zinc. Analysis of %RDA or %AI was performed using principal component analysis (PCA) and hierarchical cluster analysis (HCA). Using PCA, the differentiation between products based on rice, corn, potato, GF wheat starch and based on buckwheat, chickpea, millet, oats, amaranth, teff, quinoa, chestnut, and acorn was possible. In the HCA, four clusters were created. The main criterion determining the adherence of the sample to the cluster was the content of all minerals included to HCA (K, Mg, Cu, Fe, Mn); however, only the Mn content differentiated four formed groups. GF products made of buckwheat, chickpea, millet, oats, amaranth, teff, quinoa, chestnut, and acorn are better source of minerals than based on other GF raw materials, what was confirmed by PCA and HCA. © 2017 Society of Chemical Industry. © 2017 Society of Chemical Industry.

  19. Bacterial mineralization patterns in basaltic aquifers: implications for possible life in martian meteorite ALH84001

    NASA Technical Reports Server (NTRS)

    Thomas-Keprta, K. L.; McKay, D. S.; Wentworth, S. J.; Stevens, T. O.; Taunton, A. E.; Allen, C. C.; Coleman, A.; Gibson, E. K. Jr; Romanek, C. S.

    1998-01-01

    To explore the formation and preservation of biogenic features in igneous rocks, we have examined the organisms in experimental basaltic microcosms using scanning and transmission electron microscopy. Four types of microorganisms were recognized on the basis of size, morphology, and chemical composition. Some of the organisms mineralized rapidly, whereas others show no evidence of mineralization. Many mineralized cells are hollow and do not contain evidence of microstructure. Filaments, either attached or no longer attached to organisms, are common. Unattached filaments are mineralized and are most likely bacterial appendages (e.g., prosthecae). Features similar in size and morphology to unattached, mineralized filaments are recognized in martian meteorite ALH84001.

  20. 42 CFR 37.60 - Submitting required chest roentgenograms and miner identification documents.

    Code of Federal Regulations, 2013 CFR

    2013-10-01

    ... format specified by NIOSH either using portable electronic media, or a secure electronic file transfer... forms shall be submitted with his or her name and social security account number on each. If any of the... containing the miner's name, address, social security number and place of employment. [43 FR 33715, Aug. 1...

  1. Microstructural features of carious human enamel imaged with back-scattered electrons.

    PubMed

    Pearce, E I; Nelson, D G

    1989-02-01

    We have used back-scattered electrons (BE) in the scanning electron microscope to produce mineral density images of enamel. Flat surfaces of artificially-carious enamel, softened in an intra-oral experiment, and naturally-carious (white spot) enamel were polished to a high gloss with diamond lapping compound, rendering them almost featureless by secondary electron scanning electron microscopy. They were then examined at 10 to 30 kV in a Philips 505 instrument fitted with a 4-quadrant BE detector. Study of surfaces prepared approximately parallel to the natural surface showed that mineral was lost from both prism core and the interprismatic region, leaving a thin mineral-rich rim at the prism periphery. The same lesions viewed longitudinally on a surface prepared perpendicular to the natural surface showed mineral-rich bands at the prism margins in the outer enamel. Near the advancing front of the lesion, the prism junctions were widened and the prism cores sometimes hypermineralized. Natural lesions sectioned in the prism long axis showed features previously seen with other techniques, e.g., cross-striations and striae of Retzius, but in much greater detail. Mineral enrichment at the prism periphery in the lesion body and a widening of the prism junction at the advancing fronts of lesions in permanent teeth were most obvious. Calculations showed that with an accelerating voltage of 30 kV, the images reflected mineral density up to 4 microns beneath the surface. BE microscopy produces a high-resolution image of mineral loss or gain in carious enamel, with relatively easy sample preparation.

  2. Role of mineralization inhibitors in the regulation of hard tissue biomineralization: relevance to initial enamel formation and maturation

    PubMed Central

    Margolis, Henry C.; Kwak, Seo-Young; Yamazaki, Hajime

    2014-01-01

    Vertebrate mineralized tissues, i.e., enamel, dentin, cementum, and bone, have unique hierarchical structures and chemical compositions. Although these tissues are similarly comprised of a crystalline calcium apatite mineral phase and a protein component, they differ with respect to crystal size and shape, level and distribution of trace mineral ions, the nature of the proteins present, and their relative proportions of mineral and protein components. Despite apparent differences, mineralized tissues are similarly derived by highly concerted extracellular processes involving matrix proteins, proteases, and mineral ion fluxes that collectively regulate the nucleation, growth and organization of forming mineral crystals. Nature, however, provides multiple ways to control the onset, rate, location, and organization of mineral deposits in developing mineralized tissues. Although our knowledge is quite limited in some of these areas, recent evidence suggests that hard tissue formation is, in part, controlled through the regulation of specific molecules that inhibit the mineralization process. This paper addresses the role of mineralization inhibitors in the regulation of biological mineralization with emphasis on the relevance of current findings to the process of amelogenesis. Mineralization inhibitors can also serve to maintain driving forces for calcium phosphate precipitation and prevent unwanted mineralization. Recent evidence shows that native phosphorylated amelogenins have the capacity to prevent mineralization through the stabilization of an amorphous calcium phosphate precursor phase, as observed in vitro and in developing teeth. Based on present findings, the authors propose that the transformation of initially formed amorphous mineral deposits to enamel crystals is an active process associated with the enzymatic processing of amelogenins. Such processing may serve to control both initial enamel crystal formation and subsequent maturation. PMID:25309443

  3. Separation and identification of the silt-sized heavy-mineral fraction in sediments

    USGS Publications Warehouse

    Commeau, Judith A.; Poppe, Lawrence J.; Commeau, R.F.

    1992-01-01

    The separation of silt-sized minerals by specific gravity is made possible by using a nontoxic, heavy liquid medium of sodium polytungstate and water. Once separated, the silt-sized heavy-mineral fraction is prepared for analysis with a scanning electron microscope equipped with an automatic image analyzer and energy-dispersive spectrometer. Particles within each sample are sized and sorted according to their chemistry, and the data are tabulated in histograms and tables. Where possible, the user can define the chemical categories to simulate distinct mineral groups. Polymorphs and minerals that have overlapping compositions are combined into a group and differentiated by X-ray diffraction. Hundreds of particles can be rapidly sized and classified by chemistry. The technique can be employed on sediments from any environment.

  4. Titanium minerals of placer deposits as a source for new materials

    NASA Astrophysics Data System (ADS)

    Kotova, Olga; Ponaryadov, Alexey

    2015-04-01

    Heavy mineral deposits are a source of the economic important element titanium, which is contained in ilmenite and leucoxene. The mineral composition of placer titanium ore and localization pattern of ore minerals determine their processing and enriching technologies. New data on the mineralogy of titanium ores from modern coastal-marine placer in Stradbroke Island, Eastern Australia, and Pizhma paleoplacer in Middle Timan, Russia, and materials on their basis are presented. The samples were studied by the following methods: optical-mineralogical (stereomicroscope MBS-10, polarizing microscope POLAM L-311), semiquantitative x-ray phase analysis (x-ray difractometer X'Pert PRO MPD). Besides microprobe (VEGA 3 TESCAN) and x-ray fluorescent analysis (XRF-1800 Shimadzu) were used. By the mineralogical composition ores of the both deposits are complex: enriched by valuable minerals. Apart from main ore concentrates it is possible to obtain accompanying nonmetallic products. This will increase the efficiency of deposit exploitation. Ilmenite dominates in ore sands of Stradbroke Island, and leucoxene dominates in the ores of the Pizhma titanium deposit. Australian ilmenite and its altered varieties are mainly characterized by a very high MnO content (from 5.24 to 11.08 %). The irregular distribution of iron oxides, titanium and manganese in the altered ilmenite was shown in the paper. E.g., in the areas of substitution of ilmenite by pseudorutile the concentrations of the given elements are greatly various due to various ratios of basic components in each grain. Their ratios are equal in the area of rutile evolution. Moreover, the high content of gold, diamonds and also rare earth elements (REE) and rare metals (their forms are not determined) were studied. We found native copper on the surface of minerals composing titanium-bearing sandstones of the Pizhma placer. According to the technological features of rocks (density and magnetic) studied placers are close. The

  5. The mineral economy of Brazil--Economia mineral do Brasil

    USGS Publications Warehouse

    Gurmendi, Alfredo C.; Barboza, Frederico Lopes; Thorman, Charles H.

    1999-01-01

    This study depicts the Brazilian government structure, mineral legislation and investment policy, taxation, foreign investment policies, environmental laws and regulations, and conditions in which the mineral industry operates. The report underlines Brazil's large and diversified mineral endowment. A total of 37 mineral commodities, or groups of closely related commodities, is discussed. An overview of the geologic setting of the major mineral deposits is presented. This report is presented in English and Portuguese in pdf format.

  6. Mineral carbonation of gaseous carbon dioxide using a clay-hosted cation exchange reaction.

    PubMed

    Kang, Il-Mo; Roh, Ki-Min

    2013-01-01

    The mineral carbonation method is still a challenge in practical application owing to: (1) slow reaction kinetics, (2) high reaction temperature, and (3) continuous mineral consumption. These constraints stem from the mode of supplying alkaline earth metals through mineral acidification and dissolution. Here, we attempt to mineralize gaseous carbon dioxide into calcium carbonate, using a cation exchange reaction of vermiculite (a species of expandable clay minerals). The mineralization is operated by draining NaCI solution through vermiculite powders and continuously dropping into the pool of NaOH solution with CO2 gas injected. The mineralization temperature is regulated here at 293 and 333 K for 15 min. As a result of characterization, using an X-ray powder diffractometer and a scanning electron microscopy, two types of pure CaCO3 polymorphs (vaterite and calcite) are identified as main reaction products. Their abundance and morphology are heavily dependent on the mineralization temperature. Noticeably, spindle-shaped vaterite, which is quite different from a typical vaterite morphology (polycrystalline spherulite), forms predominantly at 333 K (approximately 98 wt%).

  7. Trace Mineral Micronutrients and Chronic Periodontitis-a Review.

    PubMed

    Gaur, Sumit; Agnihotri, Rupali

    2017-04-01

    Trace mineral micronutrients are imperative for optimum host response. Populations worldwide are prone to their insufficiency owing to lifestyle changes or poor nutritional intake. Balanced levels of trace minerals like iron (Fe), zinc (Zn), selenium (Se) and copper (Cu) are essential to prevent progression of chronic conditions like periodontitis. Their excess as well as deficiency is detrimental to periodontal health. This is specifically true in relation to Fe. Furthermore, some trace elements, e.g. Se, Zn and Cu are integral components of antioxidant enzymes and prevent reactive oxygen species induced destruction of tissues. Their deficiency can worsen periodontitis associated with systemic conditions like diabetes mellitus. With this background, the present review first focusses on the role of four trace minerals, namely, Fe, Zn, Se and Cu in periodontal health followed by an appraisal of the data from case control studies related to their association with chronic periodontitis.

  8. The study of ionization by electron impact of a substance simulating spent nuclear fuel components

    NASA Astrophysics Data System (ADS)

    Antonov, N. N.; Bochkarev, E. I.; Gavrikov, A. V.; Samokhin, A. A.; Smirnov, V. P.

    2015-11-01

    Plasma sources of model substances are necessary to solve problems associated with development of the spent nuclear fuel (SNF) plasma separation method. Lead was chosen to simulate kinetic and dynamic properties of the heavy SNF components. In this paper we present the results of a study of a lead vapor discharge with a lead concentration of 1012-1013 cm-3. Ionization was carried out by an electron beam (with energy of up to 500 eV per electron) inside a centimeter gap between planar electrodes. The discharge was numerically modeled using the hydrodynamic and single-particle approximation. Current-voltage characteristics and single ionization efficiency were obtained as functions of the vapors concentration and thermoelectric current. An ion current of hundreds of microamperes at the ionization efficiency near tenths of a percent was experimentally obtained. These results are in good agreement with our model.

  9. XPEEM valence state imaging of mineral micro-intergrowths with a spatial resolution of 100nm

    NASA Astrophysics Data System (ADS)

    Smith, A. D.; Schofield, P. F.; Scholl, A.; Pattrick, R. A. D.; Bridges, J. C.

    2003-03-01

    The crystal chemistry and textural relationships of minerals hold a vast amount of information relating to the formation, history and stability of natural materials. The application of soft X-ray spectroscopy to mineralogical material has revealed that 2p (L{2,3}) spectra provide a sensitive fingerprint of the electronic states of 3d metals. In bulk powdered samples much of the textural and microstructural information is lost, but the area-selectivity capability of X-ray Photo-Emission Electron Microscopy (XPEEM) provides the ability to obtain valence state information from mineral intergrowths with a submicron spatial resolution. Using the state-of-the-art PEEM2 facility on beamline 7.3.1.1 at the Advanced Light Source, Berkeley, USA, a range of minerals, mineral intergrowths and mineralogical textures have been studied for a broad suite of geological, planetary and environmental science materials. High-quality, multi-element valence images have been obtained showing the distribution/variation of the metal valence states across single grains or mineral intergrowths/textures at the l00 nm scale and quantitative valence state ratios can be obtained from areas of 0.01 μ m^2.

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

    NASA Astrophysics Data System (ADS)

    Chanturiya, V. A.

    2008-12-01

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

  11. Connecting the irreversible capacity loss in Li-ion batteries with the electronic insulating properties of solid electrolyte interphase (SEI) components.

    DOE PAGES

    Leung, Kevin; Lin, Yu -Xiao; Liu, Zhe; ...

    2016-01-01

    The formation and continuous growth of a solid electrolyte interphase (SEI) layer are responsible for the irreversible capacity loss of batteries in the initial and subsequent cycles, respectively. In this article, the electron tunneling barriers from Li metal through three insulating SEI components, namely Li 2CO 3, LiF and Li 3PO 4, are computed by density function theory (DFT) approaches. Based on electron tunneling theory, it is estimated that sufficient to block electron tunneling. It is also found that the band gap decreases under tension while the work function remains the same, and thus the tunneling barrier decreases under tensionmore » and increases under compression. A new parameter, η, characterizing the average distances between anions, is proposed to unify the variation of band gap with strain under different loading conditions into a single linear function of η. An analytical model based on the tunneling results is developed to connect the irreversible capacity loss, due to the Li ions consumed in forming these SEI component layers on the surface of negative electrodes. As a result, the agreement between the model predictions and experimental results suggests that only the initial irreversible capacity loss is due to the self-limiting electron tunneling property of the SEI.« less

  12. 30 CFR 75.1103-2 - Automatic fire sensors; approved components; installation requirements.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... 30 Mineral Resources 1 2010-07-01 2010-07-01 false Automatic fire sensors; approved components... Protection § 75.1103-2 Automatic fire sensors; approved components; installation requirements. (a) The components of each automatic fire sensor required to be installed in accordance with the provisions of § 75...

  13. 30 CFR 75.1103-2 - Automatic fire sensors; approved components; installation requirements.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... 30 Mineral Resources 1 2011-07-01 2011-07-01 false Automatic fire sensors; approved components... Protection § 75.1103-2 Automatic fire sensors; approved components; installation requirements. (a) The components of each automatic fire sensor required to be installed in accordance with the provisions of § 75...

  14. 30 CFR 75.1103-2 - Automatic fire sensors; approved components; installation requirements.

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... 30 Mineral Resources 1 2014-07-01 2014-07-01 false Automatic fire sensors; approved components... Protection § 75.1103-2 Automatic fire sensors; approved components; installation requirements. (a) The components of each automatic fire sensor required to be installed in accordance with the provisions of § 75...

  15. 30 CFR 75.1103-2 - Automatic fire sensors; approved components; installation requirements.

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... 30 Mineral Resources 1 2012-07-01 2012-07-01 false Automatic fire sensors; approved components... Protection § 75.1103-2 Automatic fire sensors; approved components; installation requirements. (a) The components of each automatic fire sensor required to be installed in accordance with the provisions of § 75...

  16. 30 CFR 75.1103-2 - Automatic fire sensors; approved components; installation requirements.

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... 30 Mineral Resources 1 2013-07-01 2013-07-01 false Automatic fire sensors; approved components... Protection § 75.1103-2 Automatic fire sensors; approved components; installation requirements. (a) The components of each automatic fire sensor required to be installed in accordance with the provisions of § 75...

  17. Laser-Assisted Atom Probe Tomography of Deformed Minerals: A Zircon Case Study.

    PubMed

    La Fontaine, Alexandre; Piazolo, Sandra; Trimby, Patrick; Yang, Limei; Cairney, Julie M

    2017-04-01

    The application of atom probe tomography to the study of minerals is a rapidly growing area. Picosecond-pulsed, ultraviolet laser (UV-355 nm) assisted atom probe tomography has been used to analyze trace element mobility within dislocations and low-angle boundaries in plastically deformed specimens of the nonconductive mineral zircon (ZrSiO4), a key material to date the earth's geological events. Here we discuss important experimental aspects inherent in the atom probe tomography investigation of this important mineral, providing insights into the challenges in atom probe tomography characterization of minerals as a whole. We studied the influence of atom probe tomography analysis parameters on features of the mass spectra, such as the thermal tail, as well as the overall data quality. Three zircon samples with different uranium and lead content were analyzed, and particular attention was paid to ion identification in the mass spectra and detection limits of the key trace elements, lead and uranium. We also discuss the correlative use of electron backscattered diffraction in a scanning electron microscope to map the deformation in the zircon grains, and the combined use of transmission Kikuchi diffraction and focused ion beam sample preparation to assist preparation of the final atom probe tip.

  18. Preliminary studies of mineralization during distraction osteogenesis.

    PubMed

    Aronson, J; Good, B; Stewart, C; Harrison, B; Harp, J

    1990-01-01

    Distraction osteogenesis by the Ilizarov method was performed on 20 dogs. Mineralization at the site of the left tibial metaphyseal lengthening was measured by weekly quantitative computer tomography (QCT) using the contralateral tibia as a control. Four dogs each were killed on Days 7, 14, 21, and 28 of distraction in order to correlate QCT with microradiology, nondecalcified histology, quantitative calcium analysis, and scanning electron microscopy. It was consistently found that intramembranous ossification proceeded centripetally from each corticotomy surface toward the central fibrous interzone. Bone columns crystallized along longitudinally oriented collagen bundles, expanding circumferentially to surrounding bundles. As the distraction gap increased, the bone columns increased in length and in diameter, while the fibrous interzone remained about 4 mm long. Histologically, the bone columns resembled stalagmites and stalactites, as seen by microradiography and scanning electron microscopy, that projected from each corticotomy surface toward the center. These cones reached maximum diameters of 150-200 mu at the corticotomy surfaces. Radiodensity (QCT) increased gradually from the central fibrous interzone toward each corticotomy surface. Mineral density, as determined by calcium quantification, reflected the microscopic geometry and radiographic polarity.

  19. Metals, minerals and microbes: geomicrobiology and bioremediation.

    PubMed

    Gadd, Geoffrey Michael

    2010-03-01

    Microbes play key geoactive roles in the biosphere, particularly in the areas of element biotransformations and biogeochemical cycling, metal and mineral transformations, decomposition, bioweathering, and soil and sediment formation. All kinds of microbes, including prokaryotes and eukaryotes and their symbiotic associations with each other and 'higher organisms', can contribute actively to geological phenomena, and central to many such geomicrobial processes are transformations of metals and minerals. Microbes have a variety of properties that can effect changes in metal speciation, toxicity and mobility, as well as mineral formation or mineral dissolution or deterioration. Such mechanisms are important components of natural biogeochemical cycles for metals as well as associated elements in biomass, soil, rocks and minerals, e.g. sulfur and phosphorus, and metalloids, actinides and metal radionuclides. Apart from being important in natural biosphere processes, metal and mineral transformations can have beneficial or detrimental consequences in a human context. Bioremediation is the application of biological systems to the clean-up of organic and inorganic pollution, with bacteria and fungi being the most important organisms for reclamation, immobilization or detoxification of metallic and radionuclide pollutants. Some biominerals or metallic elements deposited by microbes have catalytic and other properties in nanoparticle, crystalline or colloidal forms, and these are relevant to the development of novel biomaterials for technological and antimicrobial purposes. On the negative side, metal and mineral transformations by microbes may result in spoilage and destruction of natural and synthetic materials, rock and mineral-based building materials (e.g. concrete), acid mine drainage and associated metal pollution, biocorrosion of metals, alloys and related substances, and adverse effects on radionuclide speciation, mobility and containment, all with immense social

  20. The influence of organic substances type on the properties of mineral-organic fertilizers

    NASA Astrophysics Data System (ADS)

    Huculak-Mä Czka, Marta; Hoffmann, Krystyna; Hoffmann, Józef

    2010-05-01

    In presented research the lignite coal, peat, poultry droppings and their composts were suggested as a components of mineral-organic fertilizers. Fertility of soil is conditioned by an ability to supply plants with water and nutrients essential to their growth and development. The soil is described as tri-phase system consisting of solid, liquid and gas phase. In solid phase the soil minerals and organic matter can be distinguished. The content of micro-organisms contained in the soil i.e. microfauna and microflora is indispensable for high soil fertility. Nutrients should occur in the forms available for plants in order to obtain high yields of the high quality crops. Organic fertilizing has versatile activity. Increasing contents of humus, providing mineral nutrients included in organic substance and the improvement in physical properties of the soil belong to its main purposes. Due to applying organic fertilizers heavy soils is getting loosen and in consequence become more airy what probably influences stimulation of soil micro-organisms activity. An aqueous as well as sorption capacity of light soils is also increasing, buffer range and the stabilization of the proper level of pH value of the soil, plants are provided with basic macro and micronutrients. Conventional organic fertilizers applied in an arable farms are manure, dung, green manures and composts of different kind. Within compost group the following types can be distinguished: compost from farming, urban wastes, shredded straw, poultry droppings, industrial wastes, bark of coniferous tree etc. Properly developed fertilizer formulas should contain in their composition both mineral as well as organic elements. Such fertilizer should fit its composition to the soil and plant requirements. It should contain organic substance being characterized by a high aqueous and cations sorption capacity, substance undergoing the fast mineralization with the large calcium content. Inorganic substances e.g. bentonites

  1. Microbial community composition during anaerobic mineralization of tert-butyl alcohol (TBA) in fuel-contaminated aquifer material.

    PubMed

    Wei, Na; Finneran, Kevin T

    2011-04-01

    Anaerobic mineralization of tert-butyl alcohol (TBA) and methyl tert-butyl ether (MTBE) were studied in sediment incubations prepared with fuel-contaminated aquifer material. Microbial community compositions in all incubations were characterized by amplified ribosomal DNA restriction analysis (ARDRA). The aquifer material mineralized 42.3±9.9% of [U-(14)C]-TBA to 14CO2 without electron acceptor amendment. Fe(III), sulfate, and Fe(III) plus anthraquinone-2,6-disulfonate addition also promoted U-[14C]-TBA mineralization at levels similar to those of the unamended controls. Nitrate actually inhibited TBA mineralization relative to unamended controls. In contrast to TBA, [U-(14)C]-MTBE was not significantly mineralized in 400 days regardless of electron acceptor amendment. Microbial community analysis indicated that the abundance of one dominant clone group correlated closely with anaerobic TBA mineralization. The clone was phylogenetically distinct from known aerobic TBA-degrading microorganisms, Fe(III)- or sulfate-reducing bacteria. It was most closely associated with organisms belonging to the alphaproteobacteria. Microbial communities were different in MTBE and TBA amended incubations. Shannon indices and Simpson indices (statistical community comparison tools) both demonstrated that microbial community diversity decreased in incubations actively mineralizing TBA, with distinct "dominant" clones developing. These data contribute to our understanding of anaerobic microbial transformation of fuel oxygenates in contaminated aquifer material and the organisms that may catalyze the reactions.

  2. Analysis of mixed-layer clay mineral structures

    USGS Publications Warehouse

    Bradley, W.F.

    1953-01-01

    Among the enormously abundant natural occurrences of clay minerals, many examples are encountered in which no single specific crystallization scheme extends through a single ultimate grain. The characterization of such assemblages becomes an analysis of the distribution of matter within such grains, rather than the simple identification of mineral species. It having become established that the particular coordination complex typified by mica is a common component of many natural subcrystalline assemblages, the opportunity is afforded to analyze scattering from random associations of these complexes with other structural units. Successful analyses have been made of mixed hydration states of montmorillonite, of montmorillonite with mica, of vermiculite with mica, and of montmorillonite with chlorite, all of which are variants of the mica complex, and of halloysite with hydrated halloysite.

  3. ELECTRONIC COMPONENT COOLING ALTERNATIVES: COMPRESSED AIR & LIQUID NITROGEN

    EPA Science Inventory

    The goal of this study was to evaluate tools used to troubleshoot circuit boards with known or suspected thermally intermittent components. ailure modes for thermally intermittent components are typically mechanical defects, such as cracks in solder paths or joints, or broken bon...

  4. Controllable mineral coatings on PCL scaffolds as carriers for growth factor release

    PubMed Central

    Suárez-González, Darilis; Barnhart, Kara; Migneco, Francesco; Flanagan, Colleen; Hollister, Scott J.; Murphy, William L.

    2011-01-01

    In this study, we have developed mineral coatings on polycaprolactone scaffolds to serve as templates for growth factor binding and release. Mineral coatings were formed using a biomimetic approach that consisted in the incubation of scaffolds in modified simulated body fluids (mSBF). To modulate the properties of the mineral coating, which we hypothesized would dictate growth factor release, we used carbonate (HCO3) concentration in mSBF of 4.2 mM, 25mM, and 100mM. Analysis of the mineral coatings formed using scanning electron microscopy indicated growth of a continuous layer of mineral with different morphologies. X-ray diffraction analysis showed peaks associated with hydroxyapatite, the major inorganic constituent of human bone tissue in coatings formed in all HCO3 concentrations. Mineral coatings with increased HCO3 substitution showed more rapid dissolution kinetics in an environment deficient in calcium and phosphate but showed re-precipitation in an environment with the aforementioned ions. The mineral coating provided an effective mechanism for growth factor binding and release. Peptide versions of vascular endothelial growth factor (VEGF) and bone morphogenetic protein 2 (BMP2) were bound with efficiencies up to 90% to mineral mineral-coated PCL scaffolds. We also demonstrated sustained release of all growth factors with release kinetics that were strongly dependent in the solubility of the mineral coating. PMID:22014948

  5. Osteoblasts generate harder, stiffer, and more delamination-resistant mineralized tissue on titanium than on polystyrene, associated with distinct tissue micro- and ultrastructure.

    PubMed

    Saruwatari, Lei; Aita, Hideki; Butz, Frank; Nakamura, Hiromi K; Ouyang, Jianyong; Yang, Yang; Chiou, Wen-An; Ogawa, Takahiro

    2005-11-01

    This study revealed that osteoblasts generate harder, stiffer, and more delamination-resistant mineralized tissue on titanium than on the tissue culture polystyrene, associated with modulated gene expression, uniform mineralization, well-crystallized interfacial calcium-phosphate layer, and intensive collagen deposition. Knowledge of this titanium-induced alteration of osteogenic potential leading to enhanced intrinsic biomechanical properties of mineralized tissue provides novel opportunities and implications for understanding and improving bone-titanium integration and engineering physiomechanically tolerant bone. Bone-titanium integration is a biological phenomenon characterized by continuous generation and preservation of peri-implant bone and serves as endosseous anchors against endogenous and exogenous loading, of which mechanisms are poorly understood. This study determines the intrinsic biomechanical properties and interfacial strength of cultured mineralized tissue on titanium and characterizes the tissue structure as possible contributing factors in biomechanical modulation. Rat bone marrow-derived osteoblastic cells were cultured either on a tissue culture-grade polystyrene dish or titanium-coated polystyrene dish having comparable surface topography. Nano-indentation and nano-scratch tests were undertaken on mineralized tissues cultured for 28 days to evaluate its hardness, elastic modulus, and critical load (force required to delaminate tissue). Gene expression was analyzed using RT-PCR. The tissue structural properties were examined by scanning electron microscopy (SEM), collagen colorimetry and localization with Sirius red stain, mineral quantification, and localization with von Kossa stain and transmission electron microscopy (TEM). Hardness and elastic modulus of mineralized tissue on titanium were three and two times greater, respectively, than those on the polystyrene. Three times greater force was required to delaminate the tissue on titanium

  6. Effects of nutritional components on aging

    PubMed Central

    Lee, Dongyeop; Hwang, Wooseon; Artan, Murat; Jeong, Dae-Eun; Lee, Seung-Jae

    2015-01-01

    Nutrients including carbohydrates, proteins, lipids, vitamins, and minerals regulate various physiological processes and are essential for the survival of organisms. Reduced overall caloric intake delays aging in various organisms. However, the role of each nutritional component in the regulation of lifespan is not well established. In this review, we describe recent studies focused on the regulatory role of each type of nutrient in aging. Moreover, we will discuss how the amount or composition of each nutritional component may influence longevity or health in humans. PMID:25339542

  7. A quantitative estimation of the exhaust, abrasion and resuspension components of particulate traffic emissions using electron microscopy

    NASA Astrophysics Data System (ADS)

    Weinbruch, Stephan; Worringen, Annette; Ebert, Martin; Scheuvens, Dirk; Kandler, Konrad; Pfeffer, Ulrich; Bruckmann, Peter

    2014-12-01

    The contribution of the three traffic-related components exhaust, abrasion, and resuspension to kerbside and urban background PM10 and PM1 levels was quantified based on the analysis of individual particles by scanning electron microscopy. A total of 160 samples was collected on 38 days between February and September 2009 at a kerbside and an urban background station in the urban/industrial Ruhr area (Germany). Based on size, morphology, chemical composition and stability under electron bombardment, the 111,003 particles studied in detail were classified into the following 14 particle classes: traffic/exhaust, traffic/abrasion, traffic/resuspension, carbonaceous/organic, industry/metallurgy, industry/power plants, secondary particles, (aged) sea salt, silicates, Ca sulfates, carbonates, Fe oxides/hydroxides, biological particles, and other particles. The traffic/exhaust component consists predominantly of externally mixed soot particles and soot internally mixed with secondary particles. The traffic/abrasion component contains all particles with characteristic tracer elements (Fe, Cu, Ba, Sb, Zn) for brake and tire abrasion. The traffic/resuspension component is defined by the mixing state and comprises all internally mixed particles with a high proportion of silicates or Fe oxides/hydroxides which contain soot or abrasion particles as minor constituent. In addition, silicates and Fe oxides/hydroxides internally mixed with chlorine and sulphur containing particles were also assigned to the traffic/resuspension component. The total contribution of traffic to PM10 was found to be 27% at the urban background station and 48% at the kerbside station, the corresponding values for PM1 are 15% and 39%. These values lie within the range reported in previous literature. The relative share of the different traffic components for PM10 at the kerbside station was 27% exhaust, 15% abrasion, and 58% resuspension (38%, 8%, 54% for PM1). For the urban background, the following

  8. Nectar minerals as regulators of flower visitation in stingless bees and nectar hoarding wasps.

    PubMed

    Afik, Ohad; Delaplane, Keith S; Shafir, Sharoni; Moo-Valle, Humberto; Quezada-Euán, J Javier G

    2014-05-01

    Various nectar components have a repellent effect on flower visitors, and their adaptive advantages for the plant are not well understood. Persea americana (avocado) is an example of a plant that secretes nectar with repellent components. It was demonstrated that the mineral constituents of this nectar, mainly potassium and phosphate, are concentrated enough to repel honey bees, Apis mellifera, a pollinator often used for commercial avocado pollination. Honey bees, however, are not the natural pollinator of P. americana, a plant native to Central America. In order to understand the role of nectar minerals in plant-pollinator relationships, it is important to focus on the plant's interactions with its natural pollinators. Two species of stingless bees and one species of social wasp, all native to the Yucatan Peninsula, Mexico, part of the natural range of P. americana, were tested for their sensitivity to sugar solutions enriched with potassium and phosphate, and compared with the sensitivity of honey bees. In choice tests between control and mineral-enriched solutions, all three native species were indifferent for mineral concentrations lower than those naturally occurring in P. americana nectar. Repellence was expressed at concentrations near or exceeding natural concentrations. The threshold point at which native pollinators showed repellence to increasing levels of minerals was higher than that detected for honey bees. The results do not support the hypothesis that high mineral content is attractive for native Hymenopteran pollinators; nevertheless, nectar mineral composition may still have a role in regulating flower visitors through different levels of repellency.

  9. Mineral resource of the month: beryllium

    USGS Publications Warehouse

    ,

    2013-01-01

    The article discusses information about Beryllium. It notes that Beryllium is a light metal that has a gray color. The metal is used in the production of parts and devices including bearings, computer-chip heat sinks, and output windows of X-ray tubes. The article mentions Beryllium's discovery in 1798 by French chemist, Louis-Nicolas Vanquelin. It cites that bertrandite and beryl are the principal mineral components for the commercial production of beryllium.

  10. The petrogenesis of L-6 chondrites - Insights from the chemistry of minerals

    NASA Technical Reports Server (NTRS)

    Curtis, D. B.; Schmitt, R. A.

    1979-01-01

    Measurements of the major, minor and trace element abundances of the major minerals of the L-6 chondrites Alfianello, Colby (WI) and Leedey are used to investigate the formation mechanisms of L-6 chondrites. Electron microprobe analysis was performed on individual grains of each mineral, and separated minerals were analyzed by instrumental and radiochemical neutron activation analysis. The compositions of the three meteorites are observed to be generally uniform, however different abundances and distributions of rare earth elements and Co and Ni indicate that the meteorites have different petrogenetic histories. Alkali element distributions are found to be incompatible with internal equilibration of a closed system.

  11. Electron spin resonance as a high sensitivity technique for environmental magnetism: determination of contamination in carbonate sediments

    NASA Astrophysics Data System (ADS)

    Crook, Nigel P.; Hoon, Stephen R.; Taylor, Kevin G.; Perry, Chris T.

    2002-05-01

    This study investigates the application of high sensitivity electron spin resonance (ESR) to environmental magnetism in conjunction with the more conventional techniques of magnetic susceptibility, vibrating sample magnetometry (VSM) and chemical compositional analysis. Using these techniques we have studied carbonate sediment samples from Discovery Bay, Jamaica, which has been impacted to varying degrees by a bauxite loading facility. The carbonate sediment samples contain magnetic minerals ranging from moderate to low concentrations. The ESR spectra for all sites essentially contain three components. First, a six-line spectra centred around g = 2 resulting from Mn2+ ions within a carbonate matrix; second a g = 4.3 signal from isolated Fe3+ ions incorporated as impurities within minerals such as gibbsite, kaolinite or quartz; third a ferrimagnetic resonance with a maxima at 230 mT resulting from the ferrimagnetic minerals present within the bauxite contamination. Depending upon the location of the sites within the embayment these signals vary in their relative amplitude in a systematic manner related to the degree of bauxite input. Analysis of the ESR spectral components reveals linear relationships between the amplitude of the Mn2+ and ferrimagnetic signals and total Mn and Fe concentrations. To assist in determining the origin of the ESR signals coral and bauxite reference samples were employed. Coral representative of the matrix of the sediment was taken remote from the bauxite loading facility whilst pure bauxite was collected from nearby mining facilities. We find ESR to be a very sensitive technique particularly appropriate to magnetic analysis of ferri- and para-magnetic components within environmental samples otherwise dominated by diamagnetic (carbonate) minerals. When employing typical sample masses of 200 mg the practical detection limit of ESR to ferri- and para-magnetic minerals within a diamagnetic carbonate matrix is of the order of 1 ppm and 1 ppb

  12. Isotopic data for Late Cretaceous intrusions and associated altered and mineralized rocks in the Big Belt Mountains, Montana

    USGS Publications Warehouse

    du Bray, Edward A.; Unruh, Daniel M.; Hofstra, Albert H.

    2017-03-07

    The quartz monzodiorite of Mount Edith and the concentrically zoned intrusive suite of Boulder Baldy constitute the principal Late Cretaceous igneous intrusions hosted by Mesoproterozoic sedimentary rocks of the Newland Formation in the Big Belt Mountains, Montana. These calc-alkaline plutonic masses are manifestations of subduction-related magmatism that prevailed along the western edge of North America during the Cretaceous. Radiogenic isotope data for neodymium, strontium, and lead indicate that the petrogenesis of the associated magmas involved a combination of (1) sources that were compositionally heterogeneous at the scale of the geographically restricted intrusive rocks in the Big Belt Mountains and (2) variable contamination by crustal assimilants also having diverse isotopic compositions. Altered and mineralized rocks temporally, spatially, and genetically related to these intrusions manifest at least two isotopically distinct mineralizing events, both of which involve major inputs from spatially associated Late Cretaceous igneous rocks. Alteration and mineralization of rock associated with the intrusive suite of Boulder Baldy requires a component characterized by significantly more radiogenic strontium than that characteristic of the associated igneous rocks. However, the source of such a component was not identified in the Big Belt Mountains. Similarly, altered and mineralized rocks associated with the quartz monzodiorite of Mount Edith include a component characterized by significantly more radiogenic strontium and lead, particularly as defined by 207Pb/204Pb values. The source of this component appears to be fluids that equilibrated with proximal Newland Formation rocks. Oxygen isotope data for rocks of the intrusive suite of Boulder Baldy are similar to those of subduction-related magmatism that include mantle-derived components; oxygen isotope data for altered and mineralized equivalents are slightly lighter.

  13. 30 CFR 27.35 - Tests to determine life of critical components and subassemblies.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... 30 Mineral Resources 1 2010-07-01 2010-07-01 false Tests to determine life of critical components and subassemblies. 27.35 Section 27.35 Mineral Resources MINE SAFETY AND HEALTH ADMINISTRATION, DEPARTMENT OF LABOR TESTING, EVALUATION, AND APPROVAL OF MINING PRODUCTS METHANE-MONITORING SYSTEMS Test...

  14. 30 CFR 27.35 - Tests to determine life of critical components and subassemblies.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... 30 Mineral Resources 1 2011-07-01 2011-07-01 false Tests to determine life of critical components and subassemblies. 27.35 Section 27.35 Mineral Resources MINE SAFETY AND HEALTH ADMINISTRATION, DEPARTMENT OF LABOR TESTING, EVALUATION, AND APPROVAL OF MINING PRODUCTS METHANE-MONITORING SYSTEMS Test...

  15. Microbial Impacts on Clay Mineral Transformation and Reactivity

    NASA Astrophysics Data System (ADS)

    Dong, H.; Jaisi, D.; Fredrickson, J.; Plymale, A.

    2006-05-01

    Clays and clay minerals are ubiquitous in soils, sedimentary rocks, and pelagic oozes. They play important roles in environmental processes such as nutrient cycling, plant growth, contaminant migration, organic matter maturation, and petroleum production. Iron is a major constituent in clay minerals, and its mobility and stability in different environmental processes is, in part, controlled by the oxidation state. Recent studies have shown that biological reduction of structural Fe(III) in clay minerals can change the physical and chemical properties of clay minerals, such as swelling, cation exchange and fixation capacity, specific surface area, color, and magnetic exchange interactions. As a result of biological reduction of Fe(III), clay minerals also undergo mineral transformations, such as dissolution of smectite and precipitation of illite, siderite and vivianite. These chemical, structural and mineralogical changes of clay minerals have a profound effect on clay mineral reactivity, such as their reactivity with organic and inorganic (i.e., heavy metals and radionuclides) contaminants. Our latest data show that biologically reduced nontronite (a smectite variety) is much more effective in reducing soluble and mobile Tc(VII) to Tc(IV) than unreduced nontronite. The reduced Tc(IV) is insoluble in groundwater and soil and thus is immobile. Biologically reduced nontronite can be prepared by microbially reducing Fe(III) in nontronite by Shewanella putrefaciens in the absence of oxygen. Approximately 30% of structurally Fe(III) can be reduced in this manner. Biogenic Fe(II) can then serve as an electron donor to reduce Tc(VII). Nearly all Fe(II) is available to reduce Tc(VII), with the rate of reduction (typically within weeks) possibly depending on the speciation of Fe(II) (surface sorbed Fe(II) vs. structural Fe(II)). Further investigations are underway to further assess the reversibility of Tc reduction upon exposure to oxygen and to elucidate Tc reduction

  16. Mineral trioxide aggregate: part 2 - a review of the material aspects.

    PubMed

    Malhotra, Neeraj; Agarwal, Antara; Mala, Kundabala

    2013-03-01

    The purpose of this two-part series is to review the composition, properties, and products of mineral trioxide aggregate (MTA) materials. PubMed and MedLine electronic databases were used to identify scientific papers from January 1991 to May 2010. Based on the selected inclusion criteria, citations were referenced from the scientific peer-reviewed dental literature. Mineral trioxide aggregate is a refined form of the parent compound, Portland cement (PC), and demonstrates a strong biocompatibility due to the high pH level and the material's ability to form hydroxyapatite. Mineral trioxide aggregate materials provide better microleakage protection than traditional endodontic materials as observed in findings from dye-leakage, fluid-filtration, protein-leakage, and bacterial penetration-leakage studies and has been recognized as a bioactive material. Various MTA commercial products are available, including gray mineral trioxide aggregate (GMTA), white mineral trioxide aggregate (WMTA), and mineral trioxide aggregate-Angelus (AMTA). Although these materials are indicated for various dental uses and applications, long-term in-vivo clinical studies are needed. Part 1 of this article highlighted and discussed the composition and characteristics of the material. Part 2 provides an overview of commercially available MTA materials.

  17. Interactions Between Snow-Adapted Organisms, Minerals and Snow in a Mars-Analog Environment, and Implications for the Possible Formation of Mineral Biosignatures

    NASA Astrophysics Data System (ADS)

    Hausrath, E.; Bartlett, C. L.; Garcia, A. H.; Tschauner, O. D.; Murray, A. E.; Raymond, J. A.

    2015-12-01

    Increasing evidence suggests that icy environments on bodies such as Mars, Europa, and Enceladus may be important potential habitats in our solar system. Life in icy environments faces many challenges, including water limitation, temperature extremes, and nutrient limitation. Understanding how life has adapted to withstand these challenges on Earth may help understand potential life on other icy worlds, and understanding the interactions of such life with minerals may help shed light on the detection of possible mineral biosignatures. Snow environments, being particularly nutrient limited, may require specific adaptations by the microbiota living there. Previous observations have suggested that associated minerals and microorganisms play an important role in snow algae micronutrient acquisition. Here, in order to interpret micronutrient uptake by snow algae, and potential formation of mineral biosignatures, we present observations of interactions between snow algae and associated microorganisms and minerals in both natural, Mars-analog environments, and laboratory experiments. Samples of snow, dust, snow algae, and microorganisms were collected from Mount Anderson Ridge, CA. Some samples were DAPI-stained and analyzed by epifluorescent microscopy, and others were freeze-dried and examined by scanning electron microscopy, synchrotron X-ray diffraction (XRD) and synchrotron X-ray fluorescence (XRF). Xenic cultures of the snow alga Chloromonas brevispina were also grown under Fe-limiting conditions with and without the Fe-containing mineral nontronite to determine impacts of the mineral on algal growth. Observations from epifluorescent microscopy show bacteria closely associated with the snow algae, consistent with a potential role in micronutrient acquisition. Particles are also present on the algal cell walls, and synchrotron-XRD and XRF observations indicate that they are Fe-rich, and may therefore be a micronutrient source. Laboratory experiments indicated

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

    NASA Technical Reports Server (NTRS)

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

    1993-01-01

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

  19. The phosphate mineral arrojadite-(KFe) and its spectroscopic characterization

    NASA Astrophysics Data System (ADS)

    Frost, Ray L.; Xi, Yunfei; Scholz, Ricardo; Horta, Laura Frota Campos

    2013-05-01

    The arrojadite-(KFe) mineral has been analyzed using a combination of scanning electron microscopy and a combination of Raman and infrared spectroscopy. The origin of the mineral is Rapid Creek sedimentary phosphatic iron formation, northern Yukon. The formula of the mineral was determined as KNaCaNa(FeMgMn)Al(PO)10.85(POOH)(OH)2. The complexity of the mineral formula is reflected in the spectroscopy. Raman bands at 975, 991 and 1005 cm-1 with shoulder bands at 951 and 1024 cm-1 are assigned to the PO43- ν1 symmetric stretching modes. The Raman bands at 1024, 1066, 1092, 1123, 1148 and 1187 cm-1 are assigned to the PO43- ν3 antisymmetric stretching modes. A series of Raman bands observed at 540, 548, 557, 583, 604, 615 and 638 cm-1 are attributed to the ν4 out of plane bending modes of the PO4 and H2PO4 units. The ν2 PO4 and H2PO4 bending modes are observed at 403, 424, 449, 463, 479 and 513 cm-1. Hydroxyl and water stretching bands are readily observed. Vibrational spectroscopy enables new information about the complex phosphate mineral arrojadite-(KFe) to be obtained.

  20. 42 CFR 37.60 - Submitting required chest radiograph classification and miner identification documents.

    Code of Federal Regulations, 2014 CFR

    2014-10-01

    ... software and format specified by NIOSH either using portable electronic media, or a secure electronic file... forms shall be submitted with his or her name and social security account number on each. If any of the... containing the miner's name, address, social security number and place of employment. [43 FR 33715, Aug. 1...

  1. Practical applications of trace minerals for dairy cattle.

    PubMed

    Overton, T R; Yasui, T

    2014-02-01

    Trace minerals have critical roles in the key interrelated systems of immune function, oxidative metabolism, and energy metabolism in ruminants. To date, the primary trace elements of interest in diets for dairy cattle have included Zn, Cu, Mn, and Se although data also support potentially important roles of Cr, Co, and Fe in diets. Trace minerals such as Zn, Cu, Mn, and Se are essential with classically defined roles as components of key antioxidant enzymes and proteins. Available evidence indicates that these trace minerals can modulate aspects of oxidative metabolism and immune function in dairy cattle, particularly during the transition period and early lactation. Chromium has been shown to influence both immune function and energy metabolism of cattle; dairy cows fed Cr during the transition period and early lactation have evidence of improved immune function, increased milk production, and decreased cytological endometritis. Factors that complicate trace mineral nutrition at the farm level include the existence of a large number of antagonisms affecting bioavailability of individual trace minerals and uncertainty in terms of requirements under all physiological and management conditions; therefore, determining the optimum level and source of trace minerals under each specific situation continues to be a challenge. Typical factorial approaches to determine requirements for dairy cattle do not account for nuances in biological function observed with supplementation with various forms and amounts of trace minerals. Trace mineral nutrition modulates production, health, and reproduction in cattle although both formal meta-analysis and informal survey of the literature reveal substantial heterogeneity of response in these outcome variables. The industry has largely moved away from oxide-based programs toward sulfate-based programs; however, some evidence favors shifting supplementation strategies further toward more bioavailable forms of inorganic and organic trace

  2. FAM20A Gene Mutation: Amelogenesis or Ectopic Mineralization?

    PubMed

    Lignon, Guilhem; Beres, Fleur; Quentric, Mickael; Rouzière, Stephan; Weil, Raphael; De La Dure-Molla, Muriel; Naveau, Adrien; Kozyraki, Renata; Dessombz, Arnaud; Berdal, Ariane

    2017-01-01

    Background and objective: FAM20A gene mutations result in enamel renal syndrome (ERS) associated with amelogenesis imperfecta (AI), nephrocalcinosis, gingival fibromatosis, and impaired tooth eruption. FAM20A would control the phosphorylation of enamel peptides and thus enamel mineralization. Here, we characterized the structure and chemical composition of unerupted tooth enamel from ERS patients and healthy subjects. Methods: Tooth sections were analyzed by Scanning Electron Microscopy (SEM), Energy Dispersive Spectroscopy (EDS), X-Ray Diffraction (XRD), and X-Ray Fluorescence (XRF). Results: SEM revealed that prisms were restricted to the inner-most enamel zones. The bulk of the mineralized matter covering the crown was formed by layers with varying electron-densities organized into lamellae and micronodules. Tissue porosity progressively increased at the periphery, ending with loose and unfused nanonodules also observed in the adjoining soft tissues. Thus, the enamel layer covering the dentin in all ERS patients (except a limited layer of enamel at the dentino-enamel junction) displayed an ultrastructural globular pattern similar to one observed in ectopic mineralization of soft tissue, notably in the gingiva of Fam20a knockout mice. XRD analysis confirmed the existence of alterations in crystallinity and composition (vs. sound enamel). XRF identified lower levels of calcium and phosphorus in ERS enamel. Finally, EDS confirmed the reduced amount of calcium in ERS enamel, which appeared similar to dentin. Conclusion: This study suggests that, after an initial normal start to amelogenesis, the bulk of the tissue covering coronal dentin would be formed by different mechanisms based on nano- to micro-nodule aggregation. This evocated ectopic mineralization process is known to intervene in several soft tissues in FAM20A gene mutant.

  3. Research of seafloor topographic analyses for a staged mineral exploration

    NASA Astrophysics Data System (ADS)

    Ikeda, M.; Kadoshima, K.; Koizumi, Y.; Yamakawa, T.; Asakawa, E.; Sumi, T.; Kose, M.

    2016-12-01

    J-MARES (Research and Development Partnership for Next Generation Technology of Marine Resources Survey, JAPAN) has been designing a low-cost and high-efficiency exploration system for seafloor hydrothermal massive sulfide (SMS) deposits in "Cross-ministerial Strategic Innovation Promotion Program (SIP)" granted by the Cabinet Office, Government of Japan since 2014. We proposed the multi-stage approach, which is designed from the regional scaled to the detail scaled survey stages through semi-detail scaled, focusing a prospective area by seafloor topographic analyses. We applied this method to the area of more than 100km x 100km around Okinawa Trough, including some well-known mineralized deposits. In the regional scale survey, we assume survey areas are more than 100 km x 100km. Then the spatial resolution of topography data should be bigger than 100m. The 500 m resolution data which is interpolated into 250 m resolution was used for extracting depression and performing principal component analysis (PCA) by the wavelength obtained from frequency analysis. As the result, we have successfully extracted the areas having the topographic features quite similar to well-known mineralized deposits. In the semi-local survey stage, we use the topography data obtained by bathymetric survey using multi-narrow beam echo-sounder. The 30m-resolution data was used for extracting depression, relative-large mounds, hills, lineaments as fault, and also for performing frequency analysis. As the result, wavelength as principal component constituting in the target area was extracted by PCA of wavelength obtained from frequency analysis. Therefore, color image was composited by using the second principal component (PC2) to the forth principal component (PC4) in which the continuity of specific wavelength was observed, and consistent with extracted lineaments. In addition, well-known mineralized deposits were discriminated in the same clusters by using clustering from PC2 to PC4.We

  4. Assessment of CO2 Mineralization and Dynamic Rock Properties at the Kemper Pilot CO2 Injection Site

    NASA Astrophysics Data System (ADS)

    Qin, F.; Kirkland, B. L.; Beckingham, L. E.

    2017-12-01

    CO2-brine-mineral reactions following CO2 injection may impact rock properties including porosity, permeability, and pore connectivity. The rate and extent of alteration largely depends on the nature and evolution of reactive mineral interfaces. In this work, the potential for geochemical reactions and the nature of the reactive mineral interface and corresponding hydrologic properties are evaluated for samples from the Lower Tuscaloosa, Washita-Fredericksburg, and Paluxy formations. These formations have been identified as future regionally extensive and attractive CO2 storage reservoirs at the CO2 Storage Complex in Kemper County, Mississippi, USA (Project ECO2S). Samples from these formations were obtained from the Geological Survey of Alabama and evaluated using a suite of complementary analyses. The mineral composition of these samples will be determined using petrography and powder X-ray Diffraction (XRD). Using these compositions, continuum-scale reactive transport simulations will be developed and the potential CO2-brine-mineral interactions will be examined. Simulations will focus on identifying potential reactive minerals as well as the corresponding rate and extent of reactions. The spatial distribution and accessibility of minerals to reactive fluids is critical to understanding mineral reaction rates and corresponding changes in the pore structure, including pore connectivity, porosity and permeability. The nature of the pore-mineral interface, and distribution of reactive minerals, will be determined through imaging analysis. Multiple 2D scanning electron microscopy (SEM) backscattered electron (BSE) images and energy dispersive x-ray spectroscopy (EDS) images will be used to create spatial maps of mineral distributions. These maps will be processed to evaluate the accessibility of reactive minerals and the potential for flow-path modifications following CO2 injection. The "Establishing an Early CO2 Storage Complex in Kemper, MS" project is funded by

  5. Impact of bran components on the quality of whole wheat bread

    USDA-ARS?s Scientific Manuscript database

    Whole grains contain components, such as dietary fiber, starch, fat, antioxidant nutrients, minerals, vitamin, lignans, and phenolic compounds, which are beneficial to human health. Most of the beneficial components are found in the germ and bran as part of a wheat kernel, which are reduced in the ...

  6. Mechanisms of Mineral Substrate Acquisition in a Thermoacidophile.

    PubMed

    Amenabar, Maximiliano J; Boyd, Eric S

    2018-06-15

    The thermoacidophile Acidianus is widely distributed in Yellowstone National Park hot springs that span large gradients in pH (1.60 to 4.84), temperature (42 to 90°C), and mineralogical composition. To characterize the potential role of flexibility in mineral-dependent energy metabolism in contributing to the widespread ecological distribution of this organism, we characterized the spectrum of minerals capable of supporting metabolism and the mechanisms that it uses to access these minerals. The energy metabolism of Acidianus strain DS80 was supported by elemental sulfur (S 0 ), a variety of iron (hydr)oxides, and arsenic sulfide. Strain DS80 reduced, oxidized, and disproportionated S 0 Cells growing via S 0 reduction and disproportionation did not require direct access to the mineral to reduce it, whereas cells growing via S 0 oxidation did require direct access, observations that are attributable to the role of H 2 S produced by S 0 reduction/disproportionation in solubilizing and increasing the bioavailability of S 0 Cells growing via iron (hydr)oxide reduction did not require access to the mineral, suggesting that the cells reduce Fe(III) that is being leached by the acidic growth medium. Cells growing via oxidation of arsenic sulfide with Fe(III) did not require access to the mineral to grow. The stoichiometry of reactants to products indicates that cells oxidize soluble As(III) released from oxidation of arsenic sulfide by aqueous Fe(III). Taken together, these observations underscore the importance of feedbacks between abiotic and biotic reactions in influencing the bioavailability of mineral substrates and defining ecological niches capable of supporting microbial metabolism. IMPORTANCE Mineral sources of electron donor and acceptor that support microbial metabolism are abundant in the natural environment. However, the spectrum of minerals capable of supporting a given microbial strain and the mechanisms that are used to access these minerals in support of

  7. Binding of Pseudomonas aeruginosa Apo-Bacterioferritin Associated Ferredoxin to Bacterioferritin B Promotes Heme Mediation of Electron Delivery and Mobilization of Core Mineral Iron†

    PubMed Central

    Weeratunga, Saroja K.; Gee, Casey E.; Lovell, Scott; Zeng, Yuhong; Woodin, Carrie L.; Rivera, Mario

    2009-01-01

    The bfrB gene from Pseudomonas aeruginosa was cloned and expressed in E. coli. The resultant protein (BfrB), which assembles into a 445.3 kDa complex0020from 24 identical subunits, binds 12 molecules of heme axially coordinated by two Met residues. BfrB, isolated with 5–10 iron atoms per protein molecule, was reconstituted with ferrous ions to prepare samples with a core mineral containing 600 ± 40 ferric ions per BfrB molecule and approximately one phosphate molecule per iron atom. In the presence of sodium dithionite or in the presence of P. aeruginosa ferredoxin NADP reductase (FPR) and NADPH the heme in BfrB remains oxidized and the core iron mineral is mobilized sluggishly. In stark contrast, addition of NADPH to a solution containing BfrB, FPR and the apo-form of P. aeruginosa bacterioferritin associated ferredoxin (apo-Bfd) results in rapid reduction of the heme in BfrB and in the efficient mobilization of the core iron mineral. Results from additional experimentation indicate that Bfd must bind to BfrB to promote heme mediation of electrons from the surface to the core to support the efficient mobilization of ferrous ions from BfrB. In this context, the thus far mysterious role of heme in bacterioferritins has been brought to the front by reconstituting BfrB with its physiological partner, apo-Bfd. These findings are discussed in the context of a model for the utilization of stored iron in which the significant upregulation of the bfd gene under low-iron conditions [Ochsner, U.A., Wilderman, P.J., Vasil, A.I., and Vasil, M.L. (2002) Mol. Microbiol. 45, 1277–1287] ensures sufficient concentrations of apo-Bfd to bind BfrB and unlock the iron stored in its core. Although these findings are in contrast to previous speculations suggesting redox mediation of electron transfer by holo-Bfd, the ability of apo-Bfd to promote iron mobilization is an economical strategy used by the cell because it obviates the need to further deplete cellular iron levels to

  8. 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 is...

  9. 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 is...

  10. 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 is...

  11. Spin-orbit coupling calculations with the two-component normalized elimination of the small component method

    NASA Astrophysics Data System (ADS)

    Filatov, Michael; Zou, Wenli; Cremer, Dieter

    2013-07-01

    A new algorithm for the two-component Normalized Elimination of the Small Component (2cNESC) method is presented and tested in the calculation of spin-orbit (SO) splittings for a series of heavy atoms and their molecules. The 2cNESC is a Dirac-exact method that employs the exact two-component one-electron Hamiltonian and thus leads to exact Dirac SO splittings for one-electron atoms. For many-electron atoms and molecules, the effect of the two-electron SO interaction is modeled by a screened nucleus potential using effective nuclear charges as proposed by Boettger [Phys. Rev. B 62, 7809 (2000), 10.1103/PhysRevB.62.7809]. The use of the screened nucleus potential for the two-electron SO interaction leads to accurate spinor energy splittings, for which the deviations from the accurate Dirac Fock-Coulomb values are on the average far below the deviations observed for other effective one-electron SO operators. For hydrogen halides HX (X = F, Cl, Br, I, At, and Uus) and mercury dihalides HgX2 (X = F, Cl, Br, I) trends in spinor energies and SO splittings as obtained with the 2cNESC method are analyzed and discussed on the basis of coupling schemes and the electronegativity of X.

  12. Molecular orbital (SCF-Xα-SW) theory of metal-metal charge transfer processes in minerals

    USGS Publications Warehouse

    Sherman, David M.

    1987-01-01

    Electronic transitions between the Fe-Fe bonding and Fe-Fe antibonding orbitals results in the optically-induced intervalence charge transfer bands observed in the electronic spectra of mixed valence minerals. Such transitions are predicted to be polarized along the metal-metal bond direction, in agreement with experimental observations.

  13. Response of Microbial Soil Carbon Mineralization Rates to Oxygen Limitations

    NASA Astrophysics Data System (ADS)

    Keiluweit, M.; Denney, A.; Nico, P. S.; Fendorf, S. E.

    2014-12-01

    The rate of soil organic matter (SOM) mineralization is known to be controlled by climatic factors as well as molecular structure, mineral-organic associations, and physical protection. What remains elusive is to what extent oxygen (O2) limitations impact overall rates of microbial SOM mineralization (oxidation) in soils. Even within upland soils that are aerobic in bulk, factors limiting O2 diffusion such as texture and soil moisture can result in an abundance of anaerobic microsites in the interior of soil aggregates. Variation in ensuing anaerobic respiration pathways can further impact SOM mineralization rates. Using a combination of (first) aggregate model systems and (second) manipulations of intact field samples, we show how limitations on diffusion and carbon bioavailability interact to impose anaerobic conditions and associated respiration constraints on SOM mineralization rates. In model aggregates, we examined how particle size (soil texture) and amount of dissolved organic carbon (bioavailable carbon) affect O2 availability and distribution. Monitoring electron acceptor profiles (O2, NO3-, Mn and Fe) and SOM transformations (dissolved, particulate, mineral-associated pools) across the resulting redox gradients, we then determined the distribution of operative microbial metabolisms and their cumulative impact on SOM mineralization rates. Our results show that anaerobic conditions decrease SOM mineralization rates overall, but those are partially offset by the concurrent increases in SOM bioavailability due to transformations of protective mineral phases. In intact soil aggregates collected from soils varying in texture and SOM content, we mapped the spatial distribution of anaerobic microsites. Optode imaging, microsensor profiling and 3D tomography revealed that soil texture regulates overall O2 availability in aggregate interiors, while particulate SOM in biopores appears to control the fine-scale distribution of anaerobic microsites. Collectively, our

  14. Identification and significance of accessory minerals from a bituminous coal

    USGS Publications Warehouse

    Finkelman, R.B.; Stanton, R.W.

    1978-01-01

    A scanning electron microscope (SEM) has been used to study the in situ accessory minerals in polished blocks and pellets of petrographically analysed samples of the Waynesburg coal (hvb). Individual grains from the low-temperature ash (LTA) of the same coal were also studied. The visual resolution of the SEM permitted the detection of submicron mineral grains, which could then be analysed by the attached energy-dispersive system. Emphasis was placed on the highly reflective grains in the carbominerite bands. Among the most abundant accessory minerals observed were rutile, zircon, and rare-earth-bearing minerals. Small (1-5 ??m) particles of what may be authigenic iron-rich chromite and a nickel silicate form rims on quartz grains. The SEM also permits the observation of grain morphology and mineral intergrowths. These data are useful in determining authigenicity and diagenic alteration. Substances in density splits of LTA include authigenic, detrital, extraterrestrial magnetite, tourmaline, and evaporite (?) minerals, and a fluorine-bearing amphibole. This analytical approach allows the determination of specific sites for many of the trace elements in coals. In the Waynesburg coal, most of the chromium is in the iron-chromium rims, the fluorine is in the amphibole, and the rare-earth elements are in rare-earth-bearing minerals. The ability to relate trace-element data to specific minerals will aid in predicting the behaviour of elements in coal during combustion, liquefaction, gasification, weathering, and leaching processes. This ability also permits insight into the degree of mobility of these elements in coal and provides clues to sedimentological and diagenetic conditions. ?? 1978.

  15. An investigation of the mineral in ductile and brittle cortical mouse bone.

    PubMed

    Rodriguez-Florez, Naiara; Garcia-Tunon, Esther; Mukadam, Quresh; Saiz, Eduardo; Oldknow, Karla J; Farquharson, Colin; Millán, José Luis; Boyde, Alan; Shefelbine, Sandra J

    2015-05-01

    Bone is a strong and tough material composed of apatite mineral, organic matter, and water. Changes in composition and organization of these building blocks affect bone's mechanical integrity. Skeletal disorders often affect bone's mineral phase, either by variations in the collagen or directly altering mineralization. The aim of the current study was to explore the differences in the mineral of brittle and ductile cortical bone at the mineral (nm) and tissue (µm) levels using two mouse phenotypes. Osteogenesis imperfecta model, oim(-/-) , mice have a defect in the collagen, which leads to brittle bone; PHOSPHO1 mutants, Phospho1(-/-) , have ductile bone resulting from altered mineralization. Oim(-/-) and Phospho1(-/-) were compared with their respective wild-type controls. Femora were defatted and ground to powder to measure average mineral crystal size using X-ray diffraction (XRD) and to monitor the bulk mineral to matrix ratio via thermogravimetric analysis (TGA). XRD scans were run after TGA for phase identification to assess the fractions of hydroxyapatite and β-tricalcium phosphate. Tibiae were embedded to measure elastic properties with nanoindentation and the extent of mineralization with backscattered electron microscopy (BSE SEM). Results revealed that although both pathology models had extremely different whole-bone mechanics, they both had smaller apatite crystals, lower bulk mineral to matrix ratio, and showed more thermal conversion to β-tricalcium phosphate than their wild types, indicating deviations from stoichiometric hydroxyapatite in the original mineral. In contrast, the degree of mineralization of bone matrix was different for each strain: brittle oim(-/-) were hypermineralized, whereas ductile Phospho1(-/-) were hypomineralized. Despite differences in the mineralization, nanoscale alterations in the mineral were associated with reduced tissue elastic moduli in both pathologies. Results indicated that alterations from normal crystal size

  16. Study of the acid-base properties of mineral soil horizons using pK spectroscopy

    NASA Astrophysics Data System (ADS)

    Shamrikova, E. V.; Vanchikova, E. V.; Ryazanov, M. A.

    2007-11-01

    The presence of groups 4 and 5 participating in acid-base equilibria was revealed in samples from mineral horizons of the gley-podzolic soil of the Komi Republic using pK spectroscopy (the mathematical processing of potentiometric titration curves for plotting the distribution of acid groups according to their pK values). The specific quantity of acid-base sites in soil samples was calculated. The contribution of organic and mineral soil components to the groups of acid-base sites was estimated. The pK values of groups determining the potential, exchangeable, and unexchangeable acidities were found. The heterogeneity of acid components determining different types of soil acidity was revealed.

  17. Mineral precipitation and dissolution at two slag-disposal sites in northwestern Indiana, USA

    USGS Publications Warehouse

    Bayless, E.R.; Schulz, M.S.

    2003-01-01

    Slag is a ubiquitous byproduct of the iron- and steel-refining industries. In northwestern Indiana and northeastern Illinois, slag has been deposited over more than 52 km2 of land surface. Despite the widespread use of slag for fill and construction purposes, little is known about its chemical effects on the environment. Two slagdisposal sites were examined in northwestern Indiana where slag was deposited over the native glacial deposits. At a third site, where slag was not present, background conditions were defined. Samples were collected from cores and drill cuttings and described with scanning electron microscopy and electron microprobe analysis. Ground-water samples were collected and used to assess thermodynamic equilibria between authigenic minerals and existing conditions. Differences in the mineralogy at background and slag-affected sites were apparent. Calcite, dolomite, gypsum, iron oxides, and clay minerals were abundant in native sediments immediately beneath the slag. Mineral features indicated that these minerals precipitated rapidly from slag drainage and co-precipitated minor amounts of non-calcium metals and trace elements. Quartz fragments immediately beneath the slag showed extensive pitting that was not apparent in sediments from the background site, indicating chemical weathering by the hyperalkaline slag drainage. The environmental impacts of slag-related mineral precipitation include disruption of natural ground-water flow patterns and bed-sediment armoring in adjacent surface-water systems. Dissolution of native quartz by the hyperalkaline drainage may cause instability in structures situated over slag fill or in roadways comprised of slag aggregates.

  18. Mechanisms of electron transfer from structrual Fe(II) in reduced nontronite to oxygen for production of hydroxyl radicals

    NASA Astrophysics Data System (ADS)

    Yuan, Songhu; Liu, Xixiang; Liao, Wenjuan; Zhang, Peng; Wang, Xiaoming; Tong, Man

    2018-02-01

    Production of hydroxyl radicals (radOH) has been recently revealed upon oxygenation of sediments in redox-dynamic subsurface environments. In particular, Fe(II)-bearing clay minerals are the major sediment components contributing to radOH production upon oxygenation, and the produced radOH can oxidize contaminants and inactivate bacteria. Whereas, the mechanisms of radOH production from oxygenation of Fe(II)-bearing clay minerals remain elusive. The objectives of this study were to identify the structural variation of Fe(II) entities during the oxidation of Fe(II)-bearing clay minerals by O2, and to unravel the mechanisms of electron transfer within the mineral structure and from mineral to O2 for radOH production. Nontronite (NAu-2, 23% Fe) which was chemically reduced to 54.5% Fe(II) in total Fe was used as a model Fe(II)-bearing clay mineral. Production of radOH and oxidation of Fe(II) were measured during the oxidation of reduced NAu-2 by O2. A wide spectrum of spectroscopic techniques, including Fourier transform infrared spectroscopy (FTIR), Fe K-edge X-ray absorption spectroscopy (XAS), Mössbauer spectra, and X-ray photoelectron spectroscopy (XPS), were employed to explore the structural variation of Fe(II) entities in NAu-2 and the electron transfer within NAu-2 and from NAu-2 to O2. For 180 min oxidation of 1 g/L reduced NAu-2, a biphasic radOH production was observed, being quick within the initial 15 min and slow afterwards. Production of radOH correlates well with oxidation of Fe(II) in the reduced NAu-2. Within the initial 15 min, trioctahedral Fe(II)-Fe(II)-Fe(II) entities and edge Fe(II) in the reduced NAu-2 were preferentially and quickly oxidized, and electrons from the interior Fe(II)-Fe(II)-Fe(II) entities were most likely ejected from the basal siloxane plane to O2. Meanwhile, trioctahedral Fe(II)-Fe(II)-Fe(II) entities were mainly transformed to dioctahedral Fe(II)-Fe(II) entities. When the time of oxygenation was longer than 15 min

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

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    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.

  20. Influence of quantum diffraction and shielding on electron-ion collision in two-component semiclassical plasmas

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Hong, Woo-Pyo; Jung, Young-Dae, E-mail: ydjung@hanyang.ac.kr; Department of Applied Physics and Department of Bionanotechnology, Hanyang University, Ansan, Kyunggi-Do 426-791

    2015-01-15

    The influence of quantum diffraction and shielding on the electron-ion collision process is investigated in two-component semiclassical plasmas. The eikonal method and micropotential taking into account the quantum diffraction and shielding are used to obtain the eikonal scattering phase shift and the eikonal collision cross section as functions of the collision energy, density parameter, Debye length, electron de Broglie wavelength, and the impact parameter. The result shows that the quantum diffraction and shielding effects suppress the eikonal scattering phase shift as well as the differential eikonal collision cross section, especially, in small-impact parameter regions. It is also shown that themore » quantum shielding effect on the eikonal collision cross section is more important in low-collision energies. In addition, it is found that the eikonal collision cross section increases with an increase in the density parameter. The variations of the eikonal cross section due to the quantum diffraction and shielding effects are also discussed.« less

  1. Graphene oxide/oxidized carbon nanofiber/mineralized hydroxyapatite based hybrid composite for biomedical applications

    NASA Astrophysics Data System (ADS)

    Murugan, N.; Sundaramurthy, Anandhakumar; Chen, Shen-Ming; Sundramoorthy, Ashok K.

    2017-12-01

    Hydroxyapatite (Ca10(PO4)6(OH)2, HAP), a multi-mineral substituted calcium phosphate is the main mineral component of tooth enamel and bone, has become an important biomaterial for biomedical applications. However, as-synthesized HAP has poor mechanical properties and inferior wear resistance, so it is not suitable to use in bone tissue engineering applications. We report the successful incorporation of oxidized carbon nanofibers (O-CNF) and graphene oxide (GO) into the mineralized hydroxyapatite (M-HAP) which showed excellent mechanical and biological properties. GO improved the high mechanical strength and corrosion protection of the substrate in simulated body fluid (SBF) solution and promoted the viability of osteoblasts MG63 cells. As-prepared M-HAP/O-CNF/GO composite showed materials characteristics that similar to natural bone (M-HAP) with high mechanical strength. The resultant M-HAP/O-CNF/GO composite was characterized out by x-ray diffraction (XRD), field-emission scanning electron microscopy (FE-SEM), and Fourier-transform infrared spectroscopy (FT-IR), respectively. The mechanical strength of the material was determined by Vicker’s micro-hardness method and it was found that M-HAP/O-CNF/GO (468  ±  4 Hv) composite has superior mechanical properties than M-HAP (330  ±  3 Hv) and M-HAP/GO (425  ±  5 Hv) samples. In addition, antibacterial activity of the composite was studied against Staphylococcus aureus and Escherichia coli. Furthermore, the cell viability of the composite was observed in vitro against osteoblast cells. All these studies confirmed that the M-HAP/O-CNF/GO composite can be considered as potential candidate for dental and orthopedic applications.

  2. Identifying Fossil Biosignatures and Minerals in Mars Analog Materials Using Time-Resolved Raman Spectroscopy

    NASA Astrophysics Data System (ADS)

    Shkolyar, S.; Farmer, J.; Alerstam, E.; Maruyama, Y.; Blacksberg, J.

    2013-12-01

    Mars sample return has been identified as a top priority in the planetary science decadal survey. A Mars sample selection and caching mission would be the likely first step in this endeavor. Such a mission would aim to select and prioritize for return to Earth aqueously formed geological samples present at a selected site on Mars, based upon their potential for biosignature capture and preservation. If evidence of past life exists and is found, it is likely to come via the identification of fossilized carbonaceous matter of biological origin (kerogen) found in the selected samples analyzed in laboratories after return to Earth. Raman spectroscopy is considered one of the primary techniques for analyzing materials in situ and selecting the most promising samples for Earth return. We have previously performed a pilot study to better understand the complexities of identifying kerogen using Raman spectroscopy. For the study, we examined a variety of Mars analog materials representing a broad range of mineral compositions and kerogen maturities. The study revealed that kerogen identification in many of the most promising lithologies is often impeded by background fluorescence that originates from long (>10 ns to ms) and short (<1 ns) lifetime fluorophores in both the mineral matrixes and preserved organic matter in the samples. This work explores the potential for time-gated Raman spectroscopy to enable clear kerogen and mineral identifications in such samples. The JPL time-resolved Raman system uses time gating to reduce background fluorescence. It uses a custom-built SPAD (single photon avalanche diode) detector, featuring a 1-ns time-gate, and electronically variable gate delay. Results for a range of fluorescent samples show that the JPL system reduces fluorescence, allowing the identification of both kerogen and mineral components more successfully than with conventional Raman systems. In some of the most challenging samples, the detection of organic matter is

  3. Electron transfer and atom exchange between aqueous Fe(II) and structural Fe(III) in clays. Role in U and Hg(II) transformations

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Scherer, Michelle

    2016-08-31

    During this project, we investigated Fe electron transfer and atom exchange between aqueous Fe(II) and structural Fe(III) in clay minerals. We used selective chemical extractions, enriched Fe isotope tracer experiments, computational molecular modeling, and Mössbauer spectroscopy. Our findings indicate that structural Fe(III) in clay minerals is reduced by aqueous Fe(II) and that electron transfer occurs when Fe(II) is sorbed to either basal planes and edge OH-groups of clay mineral. Findings from highly enriched isotope experiments suggest that up to 30 % of the Fe atoms in the structure of some clay minerals exhanges with aqueous Fe(II). First principles calculations usingmore » a small polaron hopping approach suggest surprisingly fast electron mobility at room temperature in a nontronite clay mineral and are consistent with temperature dependent Mössbauer data Fast electron mobility suggests that electrons may be able to conduct through the mineral fast enough to enable exchange of Fe between the aqueous phase and clay mineral structure. over the time periods we observed. Our findings suggest that Fe in clay minerals is not as stable as previously thought.« less

  4. Multiple-component covalent organic frameworks

    PubMed Central

    Huang, Ning; Zhai, Lipeng; Coupry, Damien E.; Addicoat, Matthew A.; Okushita, Keiko; Nishimura, Katsuyuki; Heine, Thomas; Jiang, Donglin

    2016-01-01

    Covalent organic frameworks are a class of crystalline porous polymers that integrate molecular building blocks into periodic structures and are usually synthesized using two-component [1+1] condensation systems comprised of one knot and one linker. Here we report a general strategy based on multiple-component [1+2] and [1+3] condensation systems that enable the use of one knot and two or three linker units for the synthesis of hexagonal and tetragonal multiple-component covalent organic frameworks. Unlike two-component systems, multiple-component covalent organic frameworks feature asymmetric tiling of organic units into anisotropic skeletons and unusually shaped pores. This strategy not only expands the structural complexity of skeletons and pores but also greatly enhances their structural diversity. This synthetic platform is also widely applicable to multiple-component electron donor–acceptor systems, which lead to electronic properties that are not simply linear summations of those of the conventional [1+1] counterparts. PMID:27460607

  5. Multiple-component covalent organic frameworks

    NASA Astrophysics Data System (ADS)

    Huang, Ning; Zhai, Lipeng; Coupry, Damien E.; Addicoat, Matthew A.; Okushita, Keiko; Nishimura, Katsuyuki; Heine, Thomas; Jiang, Donglin

    2016-07-01

    Covalent organic frameworks are a class of crystalline porous polymers that integrate molecular building blocks into periodic structures and are usually synthesized using two-component [1+1] condensation systems comprised of one knot and one linker. Here we report a general strategy based on multiple-component [1+2] and [1+3] condensation systems that enable the use of one knot and two or three linker units for the synthesis of hexagonal and tetragonal multiple-component covalent organic frameworks. Unlike two-component systems, multiple-component covalent organic frameworks feature asymmetric tiling of organic units into anisotropic skeletons and unusually shaped pores. This strategy not only expands the structural complexity of skeletons and pores but also greatly enhances their structural diversity. This synthetic platform is also widely applicable to multiple-component electron donor-acceptor systems, which lead to electronic properties that are not simply linear summations of those of the conventional [1+1] counterparts.

  6. Mass transfer in fuel cells. [electron microscopy of components, thermal decomposition of Teflon, water transport, and surface tension of KOH solutions

    NASA Technical Reports Server (NTRS)

    Walker, R. D., Jr.

    1973-01-01

    Results of experiments on electron microscopy of fuel cell components, thermal decomposition of Teflon by thermogravimetry, surface area and pore size distribution measurements, water transport in fuel cells, and surface tension of KOH solutions are described.

  7. Amino acid and N mineralization dynamics in heathland soil after long-term warming and repetitive drought

    NASA Astrophysics Data System (ADS)

    Andresen, L. C.; Bode, S.; Tietema, A.; Boeckx, P.; Rütting, T.

    2015-04-01

    Monomeric organic nitrogen (N) compounds such as free amino acids (FAAs) are an important resource for both plants and soil microorganisms and a source of ammonium (NH4+) via microbial FAA mineralization. We compared gross FAA dynamics with gross N mineralization in a Dutch heathland soil using a 15N tracing technique. A special focus was made on the effects of climate change factors warming and drought, followed by rewetting. Our aims were to (1) compare FAA mineralization (NH4+ production from FAAs) with gross N mineralization, (2) assess gross FAA production rate (depolymerization) and turnover time relative to gross N mineralization rate, and (3) assess the effects of a 14 years of warming and drought treatment on these rates. The turnover of FAA in the soil was ca. 3 h, which is almost 2 orders of magnitude faster than that of NH4+ (i.e. ca. 4 days). This suggests that FAA is an extensively used resource by soil microorganisms. In control soil (i.e. no climatic treatment), the gross N mineralization rate (10 ± 2.9 μg N g-1 day-1) was 8 times smaller than the total gross FAA production rate of five AAs (alanine, valine, leucine, isoleucine, proline: 127.4 to 25.0 μg N g-1 day-1). Gross FAA mineralization (3.4 ± 0.2 μg N g-1 day-1) contributed 34% to the gross N mineralization rate and is therefore an important component of N mineralization. In the drought treatment, a 6-29% reduction in annual precipitation caused a decrease of gross FAA production by 65% and of gross FAA mineralization by 41% compared to control. On the other hand, gross N mineralization was unaffected by drought, indicating an increased mineralization of other soil organic nitrogen (SON) components. A 0.5-1.5 °C warming did not significantly affect N transformations, even though gross FAA production declined. Overall our results suggest that in heathland soil exposed to droughts a different type of SON pool is mineralized. Furthermore, compared to agricultural soils, FAA mineralization

  8. Amino acid and N mineralization dynamics in heathland soil after long-term warming and repetitive drought

    NASA Astrophysics Data System (ADS)

    Andresen, L. C.; Bode, S.; Tietema, A.; Boeckx, P.; Rütting, T.

    2014-11-01

    Monomeric organic nitrogen (N) such as free amino acids (fAA) is an important resource for both plants and soil microorganisms and is, furthermore, a source of ammonium (NH4+) via microbial fAA mineralization. We compared gross fAA dynamics with gross N mineralization in a Dutch heathland soil using 15N labelling. A special focus was made on the effects of climate change factors warming and drought, followed by rewetting. Our aims were to: (1) compare fAA mineralization (NH4+ production from fAAs) with gross N mineralization, (2) assess gross fAA production rate (depolymerization) and turnover time relative to gross N mineralization rate, and (3) assess the effects of warming and drought on these rates. The turnover of fAA in the soil was ca. 3 h, which is almost two orders of magnitude faster than that of NH4+ (i.e. ca. 4 days). This suggests that fAAs is an extensively used resource by soil microorganisms. In control soil (i.e. no climatic treatment), the gross N mineralization rate (10 ± 2.9 μg N g-1 day-1) was eight-times smaller than the summed gross fAA production rate of five AAs (alanine, valine, leucine, isoleucine, proline: 127.4 to 25.0 μg N g-1 day-1). Gross fAA mineralization (3.4 ± 0.2 μg N g-1 day-1) contributed by 34% to the gross N mineralization rate and is, thus, an important component of N mineralization. In the drought treatment, gross fAA production was reduced by 65% and gross fAA mineralization by 41%, compared to control. On the other hand, gross N mineralization was unaffected by drought, indicating an increased mineralization of other soil organic nitrogen (SON) components. Warming did not significantly affect N transformations, even though that gross fAA production was more than halved. Overall our results suggest that heathland soil exposed to droughts has a shift in the composition of the SON being mineralized. Furthermore, compared to agricultural soils, fAA mineralization was relatively less important in the investigated

  9. Vitamin C-sulfate inhibits mineralization in chondrocyte cultures: a caveat

    NASA Technical Reports Server (NTRS)

    Boskey, A. L.; Blank, R. D.; Doty, S. B.

    2001-01-01

    Differentiating chick limb-bud mesenchymal cell micro-mass cultures routinely mineralize in the presence of 10% fetal calf serum, antibiotics, 4 mM inorganic phosphate (or 2.5 mM beta-glycerophosphate), 0.3 mg/ml glutamine and either 25 microg/ml vitamin C or 5-12 microg/ml vitamin C-sulfate. The failure of these cultures to produce a mineralized matrix (assessed by electron microscopy, 45Ca uptake and Fourier transform infrared microscopy) led to the evaluation of each of these additives. We report here that the "stable" vitamin C-sulfate (ascorbic acid-2-sulfate) causes increased sulfate incorporation into the cartilage matrix. Furthermore, the release of sulfate from the vitamin C derivative appears to be responsible for the inhibition of mineral deposition, as demonstrated in cultures with equimolar amounts of vitamin C and sodium sulfate.

  10. Back-scattered electron imaging of skeletal tissues.

    PubMed

    Boyde, A; Jones, S J

    The use of solid-state back-scattered electron (BSE) detectors in the scanning electron microscopic study of skeletal tissues has been investigated. To minimize the topographic element in the image, flat samples and a ring detector configuration with the sample at normal incidence to the beam and the detector are used. Very flat samples are prepared by diamond micromilling or diamond polishing plastic-embedded tissue. Density discrimination in the image is so good that different density phases within mineralized bone can be imaged. For unembedded spongy bone, cut surfaces can be discriminated from natural surfaces by a topographic contrast mechanism. BSE imaging also presents advantages for unembedded samples with rough topography, such as anorganic preparations of the mineralization zone in cartilage, which give rise to severe charging problems with conventional secondary electron imaging.

  11. Inkjet deposited circuit components

    NASA Astrophysics Data System (ADS)

    Bidoki, S. M.; Nouri, J.; Heidari, A. A.

    2010-05-01

    All-printed electronics as a means of achieving ultra-low-cost electronic circuits has attracted great interest in recent years. Inkjet printing is one of the most promising techniques by which the circuit components can be ultimately drawn (i.e. printed) onto the substrate in one step. Here, the inkjet printing technique was used to chemically deposit silver nanoparticles (10-200 nm) simply by ejection of silver nitrate and reducing solutions onto different substrates such as paper, PET plastic film and textile fabrics. The silver patterns were tested for their functionality to work as circuit components like conductor, resistor, capacitor and inductor. Different levels of conductivity were achieved simply by changing the printing sequence, inks ratio and concentration. The highest level of conductivity achieved by an office thermal inkjet printer (300 dpi) was 5.54 × 105 S m-1 on paper. Inkjet deposited capacitors could exhibit a capacitance of more than 1.5 nF (parallel plate 45 × 45 mm2) and induction coils displayed an inductance of around 400 µH (planar coil 10 cm in diameter). Comparison of electronic performance of inkjet deposited components to the performance of conventionally etched items makes the technique highly promising for fabricating different printed electronic devices.

  12. 30 CFR 260.130 - What criteria does MMS use for selecting bidding systems and bidding system components?

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... 30 Mineral Resources 2 2010-07-01 2010-07-01 false What criteria does MMS use for selecting bidding systems and bidding system components? 260.130 Section 260.130 Mineral Resources MINERALS MANAGEMENT SERVICE, DEPARTMENT OF THE INTERIOR OFFSHORE OUTER CONTINENTAL SHELF OIL AND GAS LEASING Bidding Systems Bidding System Selection Criteria §...

  13. Korteweg-deVries-Burgers (KdVB) equation in a five component cometary plasma with kappa described electrons and ions

    NASA Astrophysics Data System (ADS)

    Michael, Manesh; Willington, Neethu T.; Jayakumar, Neethu; Sebastian, Sijo; Sreekala, G.; Venugopal, Chandu

    2016-12-01

    We investigate the existence of ion-acoustic shock waves in a five component cometary plasma consisting of positively and negatively charged oxygen ions, kappa described hydrogen ions, hot solar electrons, and slightly colder cometary electrons. The KdVB equation has been derived for the system, and its solution plotted for different kappa values, oxygen ion densities, as well as the temperature ratios for the ions. It is found that the amplitude of the shock wave decreases with increasing kappa values. The strength of the shock profile decreases with increasing temperatures of the positively charged oxygen ions and densities of negatively charged oxygen ions.

  14. Transmission Electron Microscopy of the Matrix Minerals in the Tagish Lake Carbonaceous Chondrite

    NASA Technical Reports Server (NTRS)

    Mikouchi, T.; Kasama, T.; Zolensky, M. E.; Tachikawa, O.

    2001-01-01

    We studied the Tagish Lake matrix minerals by TEM. The result shows similarities to CIs (and CRs) and differences from CMs, but its heterogeneity (e.g., carbonate abundance, saponite/serpentine ratio) suggests its complex history. Additional information is contained in the original extended abstract.

  15. Mineralization/Anti-Mineralization Networks in the Skin and Vascular Connective Tissues

    PubMed Central

    Li, Qiaoli; Uitto, Jouni

    2014-01-01

    Ectopic mineralization has been linked to several common clinical conditions with considerable morbidity and mortality. The mineralization processes, both metastatic and dystrophic, affect the skin and vascular connective tissues. There are several contributing metabolic and environmental factors that make uncovering of the precise pathomechanisms of these acquired disorders exceedingly difficult. Several relatively rare heritable disorders share phenotypic manifestations similar to those in common conditions, and, consequently, they serve as genetically controlled model systems to study the details of the mineralization process in peripheral tissues. This overview will highlight diseases with mineral deposition in the skin and vascular connective tissues, as exemplified by familial tumoral calcinosis, pseudoxanthoma elasticum, generalized arterial calcification of infancy, and arterial calcification due to CD73 deficiency. These diseases, and their corresponding mouse models, provide insight into the pathomechanisms of soft tissue mineralization and point to the existence of intricate mineralization/anti-mineralization networks in these tissues. This information is critical for understanding the pathomechanistic details of different mineralization disorders, and it has provided the perspective to develop pharmacological approaches to counteract the consequences of ectopic mineralization. PMID:23665350

  16. Regional distribution of mineral and matrix in the femurs of rats flown on Cosmos 1887 biosatellite

    NASA Technical Reports Server (NTRS)

    Mechanic, Gerald L.; Arnaud, Sara B.; Boyde, Alan; Bromage, Timothy G.; Buckendahl, Patricia

    1990-01-01

    The location and nature of the defect in mineralization known to occur in growing animals after spaceflight are studied. The distribution of bone mineral density in situ is mapped, and these images are correlated with the chemical composition of the diaphyseal bone. Concentrations of mineral and osteocalcin are found to be low in the distal half of the diaphysis and concentrations of collagen to be low with evidence of increased synthesis in the proximal half of the diaphysis of the flight bones. X-ray microtomography indicates a longitudinal gradient of decreasing mineralization toward the distal diaphysis. Analysis of embedded sections by backscattered electrons reveals patterns of mineral distribution in the proximal, central, and distal regions of the diaphysis and also shows a net reduction in mineral levels toward the distal shaft. Increases in mineral density to higher fractions in controls are less in the flight bones at all three levels.

  17. Exploration of geo-mineral compounds in granite mining soils using XRD pattern data analysis

    NASA Astrophysics Data System (ADS)

    Koteswara Reddy, G.; Yarakkula, Kiran

    2017-11-01

    The purpose of the study was to investigate the major minerals present in granite mining waste and agricultural soils near and away from mining areas. The mineral exploration of representative sub-soil samples are identified by X-Ray Diffractometer (XRD) pattern data analysis. The morphological features and quantitative elementary analysis was performed by Scanning Electron Microscopy-Energy Dispersed Spectroscopy (SEM-EDS).The XRD pattern data revealed that the major minerals are identified as Quartz, Albite, Anorthite, K-Feldspars, Muscovite, Annite, Lepidolite, Illite, Enstatite and Ferrosilite in granite waste. However, in case of agricultural farm soils the major minerals are identified as Gypsum, Calcite, Magnetite, Hematite, Muscovite, K-Feldspars and Quartz. Moreover, the agricultural soils neighbouring mining areas, the minerals are found that, the enriched Mica group minerals (Lepidolite and Illite) the enriched Orthopyroxene group minerals (Ferrosilite and Enstatite). It is observed that the Mica and Orthopyroxene group minerals are present in agricultural farm soils neighbouring mining areas and absent in agricultural farm soils away from mining areas. The study demonstrated that the chemical migration takes place at agricultural farm lands in the vicinity of the granite mining areas.

  18. Adsorption of Aqueous Crude Oil Components on the Basal Surfaces of Clay Minerals: Molecular Simulations Including Salinity and Temperature Effects

    DOE PAGES

    Greathouse, J. A.; Cygan, R. T.; Fredrich, J. T.; ...

    2017-09-28

    Molecular simulations of the adsorption of representative organic molecules onto the basal surfaces of various clay minerals were used to assess the mechanisms of enhanced oil recovery associated with salinity changes and water flooding. Simulations at the density functional theory (DFT) and classical levels provide insights into the molecular structure, binding energy, and interfacial behavior of saturate, aromatic, and resin molecules near clay mineral surfaces. Periodic DFT calculations reveal binding geometries and ion pairing mechanisms at mineral surfaces while also providing a basis for validating the classical force field approach. Through classical molecular dynamics simulations, the influence of aqueous cationsmore » at the interface and the role of water solvation are examined to better evaluate the dynamical nature of cation-organic complexes and their co-adsorption onto the clay surfaces. The extent of adsorption is controlled by the hydrophilic nature and layer charge of the clay mineral. All organic species studied showed preferential adsorption on hydrophobic mineral surfaces. However, the anionic form of the resin (decahydro-2-naphthoic acid)—expected to be prevalent at near-neutral pH conditions in petroleum reservoirs—readily adsorbs to the hydrophilic kaolinite surface through a combination of cation pairing and hydrogen bonding with surface hydroxyl groups. Analysis of cation-organic pairing in both the adsorbed and desorbed states reveals a strong preference for organic anions to coordinate with divalent calcium ions rather than monovalent sodium ions, lending support to current theories regarding low-salinity water flooding.« less

  19. Adsorption of Aqueous Crude Oil Components on the Basal Surfaces of Clay Minerals: Molecular Simulations Including Salinity and Temperature Effects

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Greathouse, J. A.; Cygan, R. T.; Fredrich, J. T.

    Molecular simulations of the adsorption of representative organic molecules onto the basal surfaces of various clay minerals were used to assess the mechanisms of enhanced oil recovery associated with salinity changes and water flooding. Simulations at the density functional theory (DFT) and classical levels provide insights into the molecular structure, binding energy, and interfacial behavior of saturate, aromatic, and resin molecules near clay mineral surfaces. Periodic DFT calculations reveal binding geometries and ion pairing mechanisms at mineral surfaces while also providing a basis for validating the classical force field approach. Through classical molecular dynamics simulations, the influence of aqueous cationsmore » at the interface and the role of water solvation are examined to better evaluate the dynamical nature of cation-organic complexes and their co-adsorption onto the clay surfaces. The extent of adsorption is controlled by the hydrophilic nature and layer charge of the clay mineral. All organic species studied showed preferential adsorption on hydrophobic mineral surfaces. However, the anionic form of the resin (decahydro-2-naphthoic acid)—expected to be prevalent at near-neutral pH conditions in petroleum reservoirs—readily adsorbs to the hydrophilic kaolinite surface through a combination of cation pairing and hydrogen bonding with surface hydroxyl groups. Analysis of cation-organic pairing in both the adsorbed and desorbed states reveals a strong preference for organic anions to coordinate with divalent calcium ions rather than monovalent sodium ions, lending support to current theories regarding low-salinity water flooding.« less

  20. Bacterial mineralization patterns in basaltic aquifers: Implications for possible life in Martian meteorite ALH84001

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Thomas-Keprta, K.L.; Wentworth, S.J.; Allen, C.C.

    To explore the formation and preservation of biogenic features in igneous rocks, the authors have examined the organisms in experimental basaltic microcosms using scanning and transmission electron microscopy. Four types of microorganisms were recognized on the basis of size, morphology, and chemical composition. Some of the organisms mineralized rapidly, whereas others show no evidence of mineralization. Many mineralized cells are hollow and do not contain evidence of microstructure. Filaments, either attached or no longer attached to organisms, are common. Unattached filaments are mineralized and are most likely bacterial appendages (e.g., prosthecae). Features similar in size and morphology to unattached, mineralizedmore » filaments are recognized in martial meteorite ALH84001.« less

  1. Composition of Mineral Produced by Dental Mesenchymal Stem Cells.

    PubMed

    Volponi, A A; Gentleman, E; Fatscher, R; Pang, Y W Y; Gentleman, M M; Sharpe, P T

    2015-11-01

    Mesenchymal stem cells isolated from different dental tissues have been described to have osteogenic/odontogenic-like differentiation capacity, but little attention has been paid to the biochemical composition of the material that each produces. Here, we used Raman spectroscopy to analyze the mineralized materials produced in vitro by different dental cell populations, and we compared them with the biochemical composition of native dental tissues. We show that different dental stem cell populations produce materials that differ in their mineral and matrix composition and that these differ from those of native dental tissues. In vitro, BCMP (bone chip mass population), SCAP (stem cells from apical papilla), and SHED (stem cells from human-exfoliated deciduous teeth) cells produce a more highly mineralized matrix when compared with that produced by PDL (periodontal ligament), DPA (dental pulp adult), and GF (gingival fibroblast) cells. Principal component analyses of Raman spectra further demonstrated that the crystallinity and carbonate substitution environments in the material produced by each cell type varied, with DPA cells, for example, producing a more carbonate-substituted mineral and with SCAP, SHED, and GF cells creating a less crystalline material when compared with other dental stem cells and native tissues. These variations in mineral composition reveal intrinsic differences in the various cell populations, which may in turn affect their specific clinical applications. © International & American Associations for Dental Research 2015.

  2. 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

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

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Bridges, J. C.; Schwenzer, S. P.; Leveille, R.

    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

  4. Composition of Mineral Produced by Dental Mesenchymal Stem Cells

    PubMed Central

    Volponi, A.A.; Gentleman, E.; Fatscher, R.; Pang, Y.W.Y.; Gentleman, M.M.; Sharpe, P.T.

    2015-01-01

    Mesenchymal stem cells isolated from different dental tissues have been described to have osteogenic/odontogenic-like differentiation capacity, but little attention has been paid to the biochemical composition of the material that each produces. Here, we used Raman spectroscopy to analyze the mineralized materials produced in vitro by different dental cell populations, and we compared them with the biochemical composition of native dental tissues. We show that different dental stem cell populations produce materials that differ in their mineral and matrix composition and that these differ from those of native dental tissues. In vitro, BCMP (bone chip mass population), SCAP (stem cells from apical papilla), and SHED (stem cells from human-exfoliated deciduous teeth) cells produce a more highly mineralized matrix when compared with that produced by PDL (periodontal ligament), DPA (dental pulp adult), and GF (gingival fibroblast) cells. Principal component analyses of Raman spectra further demonstrated that the crystallinity and carbonate substitution environments in the material produced by each cell type varied, with DPA cells, for example, producing a more carbonate-substituted mineral and with SCAP, SHED, and GF cells creating a less crystalline material when compared with other dental stem cells and native tissues. These variations in mineral composition reveal intrinsic differences in the various cell populations, which may in turn affect their specific clinical applications. PMID:26253190

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

    DOE PAGES

    Bridges, J. C.; Schwenzer, S. P.; Leveille, R.; ...

    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

  6. Removal of atmospheric features in near infrared spectra by means of principal component analysis and target transformation on Mars: I. Method

    NASA Astrophysics Data System (ADS)

    Geminale, A.; Grassi, D.; Altieri, F.; Serventi, G.; Carli, C.; Carrozzo, F. G.; Sgavetti, M.; Orosei, R.; D'Aversa, E.; Bellucci, G.; Frigeri, A.

    2015-06-01

    The aim of this work is to extract the surface contribution in the martian visible/near-infrared spectra removing the atmospheric components by means of Principal Component Analysis (PCA) and target transformation (TT). The developed technique is suitable for separating spectral components in a data set large enough to enable an effective usage of statistical methods, in support to the more common approaches to remove the gaseous component. In this context, a key role is played by the estimation, from the spectral population, of the covariance matrix that describes the statistical correlation of the signal among different points in the spectrum. As a general rule, the covariance matrix becomes more and more meaningful increasing the size of initial population, justifying therefore the importance of sizable datasets. Data collected by imaging spectrometers, such as the OMEGA (Observatoire pour la Minéralogie, l'Eau, les Glaces et l'Activité) instrument on board the ESA mission Mars Express (MEx), are particularly suitable for this purpose since it includes in the same session of observation a large number of spectra with different content of aerosols, gases and mineralogy. The methodology presented in this work has been first validated using a simulated dataset of spectra to evaluate its accuracy. Then, it has been applied to the analysis of OMEGA sessions over Nili Fossae and Mawrth Vallis regions, which have been already widely studied because of the presence of hydrated minerals. These minerals are key components of the surface to investigate the presence of liquid water flowing on the martian surface in the Noachian period. Moreover, since a correction for the atmospheric aerosols (dust) component is also applied to these observations, the present work is able to completely remove the atmospheric contribution from the analysed spectra. Once the surface reflectance, free from atmospheric contributions, has been obtained, the Modified Gaussian Model (MGM) has

  7. Microbial control of soil organic matter mineralization responses to labile carbon in subarctic climate change treatments.

    PubMed

    Rousk, Kathrin; Michelsen, Anders; Rousk, Johannes

    2016-12-01

    Half the global soil carbon (C) is held in high-latitude systems. Climate change will expose these to warming and a shift towards plant communities with more labile C input. Labile C can also increase the rate of loss of native soil organic matter (SOM); a phenomenon termed 'priming'. We investigated how warming (+1.1 °C over ambient using open top chambers) and litter addition (90 g m -2  yr -1 ) treatments in the subarctic influenced the susceptibility of SOM mineralization to priming, and its microbial underpinnings. Labile C appeared to inhibit the mineralization of C from SOM by up to 60% within hours. In contrast, the mineralization of N from SOM was stimulated by up to 300%. These responses occurred rapidly and were unrelated to microbial successional dynamics, suggesting catabolic responses. Considered separately, the labile C inhibited C mineralization is compatible with previously reported findings termed 'preferential substrate utilization' or 'negative apparent priming', while the stimulated N mineralization responses echo recent reports of 'real priming' of SOM mineralization. However, C and N mineralization responses derived from the same SOM source must be interpreted together: This suggested that the microbial SOM-use decreased in magnitude and shifted to components richer in N. This finding highlights that only considering SOM in terms of C may be simplistic, and will not capture all changes in SOM decomposition. The selective mining for N increased in climate change treatments with higher fungal dominance. In conclusion, labile C appeared to trigger catabolic responses of the resident microbial community that shifted the SOM mining to N-rich components; an effect that increased with higher fungal dominance. Extrapolating from these findings, the predicted shrub expansion in the subarctic could result in an altered microbial use of SOM, selectively mining it for N-rich components, and leading to a reduced total SOM-use. © 2016 John Wiley

  8. Experiment K-6-01. Distribution and biochemistry of mineral and matrix in the femurs of rats

    NASA Technical Reports Server (NTRS)

    Arnaud, S.; Mechanic, G.; Buckendahl, P.; Bromage, T.; Boyde, A.; Elliott, J.; Katz, E.; Durnova, G

    1990-01-01

    Previous analyses of the composition of mineral and matrix in the bone of young rats following space flight has revealed deficits in calcium, phosphorus, and osteocalcin, a non-collagenous protein, without an associated decrease in collagen. To characterize the location and nature of this mineralization defect in a weight bearing long bone, the femur, researchers attempted to relate the spatial distribution of mineral in situ in the proximal, central and distal thirds of the femoral diaphysis to the biochemical composition of bone from the same area. Biochemical analyses revealed lower concentrations of calcium, phosphorus and osteocalcin but not collagen only in the central third of the diaphysis of the flight animals (F) compared to synchronous controls (S). Collagen concentration was reduced only in the proximal third of the diaphysis, where all 3 crosslinks, expressed as nM/mol collagen were higher in F than S. A new technique, x ray microtomography, with a resolution of 26 microns, was used to obtain semi-quantitative data on mineral distribution in reconstructed sections of wet whole bone. To improve the resolution of the mineral density distribution, images of the surfaces of cut sections were analyzed by backscattered electrons in a scanning electron microscope (BSE). There was good agreement between the results of the two stereochemical techniques which revealed distinct patterns of mineralization in transverse and longitudinal directions of the diaphysis. The novel methodology developed for this flight experiment shows considerable promise in elucidating the biochemical nature of what appear to be regional alterations in the mineralization of long bones of animals exposed to spaceflight.

  9. A Direct Electric Field-Aided Biomimetic Mineralization System for Inducing the Remineralization of Dentin Collagen Matrix

    PubMed Central

    Wu, Xiao-Ting; Mei, May Lei; Li, Quan-Li; Cao, Chris Ying; Chen, Jia-Long; Xia, Rong; Zhang, Zhi-Hong; Chu, Chun Hung

    2015-01-01

    This in vitro study aimed to accelerate the remineralization of a completely demineralized dentine collagen block in order to regenerate the dentinal microstructure of calcified collagen fibrils by a novel electric field-aided biomimetic mineralization system in the absence of non-collagenous proteins. Completely demineralized human dentine slices were prepared using ethylene diamine tetraacetic acid (EDTA) and treated with guanidine hydrochloride to extract the bound non-collagenous proteins. The completely demineralized dentine collagen blocks were then remineralized in a calcium chloride agarose hydrogel and a sodium hydrogen phosphate and fluoride agarose hydrogel. This process was accelerated by subjecting the hydrogels to electrophoresis at 20 mA for 4 and 12 h. X-ray diffraction (XRD), scanning electron microscopy (SEM), energy dispersive X-ray spectroscopy (EDX), and transmission electron microscopy (TEM) were used to evaluate the resultant calcification of the dentin collagen matrix. SEM indicated that mineral particles were precipitated on the intertubular dentin collagen matrix; these densely packed crystals mimicked the structure of the original mineralized dentin. However, the dentinal tubules were not occluded by the mineral crystals. XRD and EDX both confirmed that the deposited crystals were fluorinated hydroxyapatite. TEM revealed the existence of intrafibrillar and interfibrillar mineralization of the collagen fibrils. A novel electric field-aided biomimetic mineralization system was successfully developed to remineralize a completely demineralized dentine collagen matrix in the absence of non-collagenous proteins. This study developed an accelerated biomimetic mineralization system which can be a potential protocol for the biomineralization of dentinal defects. PMID:28793685

  10. Near-infrared reflectance spectra of mixtures of kaolin-group minerals: Use in clay mineral studies

    USGS Publications Warehouse

    Crowley, James K.; Vergo, Norma

    1988-01-01

    Near-infrared (NIR) reflectance spectra for mixtures of ordered kaolinite and ordered dickite have been found to simulate the spectral response of disordered kaolinite. The amount of octahedral vacancy disorder in nine disordered kaolinite samples was estimated by comparing the sample spectra to the spectra of reference mixtures. The resulting estimates are consistent with previously published estimates of vacancy disorder for similar kaolin minerals that were modeled from calculated X-ray diffraction patterns. The ordered kaolinite and dickite samples used in the reference mixtures were carefully selected to avoid undesirable particle size effects that could bias the spectral results.NIR spectra were also recorded for laboratory mixtures of ordered kaolinite and halloysite to assess whether the spectra could be potentially useful for determining mineral proportions in natural physical mixtures of these two clays. Although the kaolinite-halloysite proportions could only be roughly estimated from the mixture spectra, the halloysite component was evident even when halloysite was present in only minor amounts. A similar approach using NIR spectra for laboratory mixtures may have applications in other studies of natural clay mixtures.

  11. 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... AND CONFLICTS Segregation § 3873.1 Segregation of mineral from non-mineral land. Where a survey is... satisfactorily established that there are existent prior unpatented mining claims, the segregation of the latter...

  12. 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.

  13. Fungal biomineralization of montmorillonite and goethite to short-range-ordered minerals

    NASA Astrophysics Data System (ADS)

    Li, Huan; Hu, Shuijin; Polizzotto, Matthew L.; Chang, Xiaoli; Shen, Qirong; Ran, Wei; Yu, Guanghui

    2016-10-01

    Highly reactive nano-scale minerals, e.g., short-range-ordered minerals (SROs) and other nanoparticles, play an important role in soil carbon (C) retention. Yet, the mechanisms that govern biomineralization from bulk minerals to highly reactive nano-scale minerals remain largely unexplored, which critically hinders our efforts toward managing nano-scale minerals for soil C retention. Here we report the results from a study that explores structural changes during Aspergillus fumigatus Z5 transformation of montmorillonite and goethite to SROs. We examined the morphology and structure of nano-scale minerals, using high-resolution transmission electron microscopy, time-resolved solid-state 27Al and 29Si NMR, and Fe K-edge X-ray absorption fine structure spectroscopy combined with two dimensional correlation spectroscopy (2D COS) analysis. Our results showed that after a 48-h cultivation of montmorillonite and goethite with Z5, new biogenic intracellular and extracellular reactive nano-scale minerals with a size of 3-5 nm became abundant. Analysis of 2D COS further suggested that montmorillonite and goethite were the precursors of the dominant biogenic nano-scale minerals. Carbon 1s near edge X-ray absorption fine structure (NEXAFS) spectra and their deconvolution results demonstrated that during fungus Z5 growth, carboxylic C (288.4-289.1 eV) was the dominant organic group, accounting for approximately 34% and 59% in the medium and aggregates, respectively. This result suggested that high percentage of the production of organic acids during the growth of Z5 was the driving factor for structural changes during biomineralization. This is, to the best of our knowledge, the first report of the structural characterization of nano-scale minerals by 2D COS, highlighting its potential to elucidate biomineralization pathways and thus identify the precursors of nano-scale minerals.

  14. Direct observation of nitrate and sulfate formations from mineral dust and sea-salts using low- Z particle electron probe X-ray microanalysis

    NASA Astrophysics Data System (ADS)

    Hwang, HeeJin; Ro, Chul-Un

    In the present work, it is demonstrated that a single particle analytical technique, named low- Z particle electron probe X-ray microanalysis, is a practically useful tool for the study of heterogeneous reactions of mineral dust and sea-salts when this analytical technique was applied to a sample collected during an Asian Dust storm event. The technique does not require a special treatment of sample to identify particles reacted in the air. Also, quantitative chemical speciation of reacted particles can provide concrete information on what chemical reaction, if any, occurred for individual particles. Among overall 178 analyzed particles, the number of reacted particles is 81 and heterogeneous chemical reactions mostly occurred on CaCO 3 mineral dust (54 particles) and sea-salts (26 particles). Several observations made for the Asian Dust sample in the present work are: (1) CaCO 3 species almost completely reacted to produce mostly Ca(NO 3) 2 species, and CaSO 4 to a much lesser extent. (2) When reacted particles contain CaSO 4, almost all of them are internally mixed with nitrate. (3) Reacted CaCO 3 particles seem to contain moisture when they were collected. (4) Some reacted CaCO 3 particles have unreacted mineral species, such as aluminosilicates, iron oxide, SiO 2, etc., in the core region. (5) All sea-salt particles are observed to have reacted in the air. Some of them were recrystallized in the air before being collected and they are observed as crystalline NaNO 3 particles. (6) Many sea-salts were collected as water drops, and some of them were fractionally recrystallized on Ag collecting substrate. When sea-salts were not recrystallized on the substrate, they are found as particles internally mixed with NaNO 3 and Mg(NO 3) 2, and in some cases SO 4 and Cl species as additional anions.

  15. International strategic minerals inventory summary report; rare-earth oxides

    USGS Publications Warehouse

    Jackson, W.D.; Christiansen, Grey

    1993-01-01

    Bastnaesite, monazite, and xenotime are currently the most important rare-earth minerals. Bastnaesite occurs as a primary mineral in carbonatites. Monazite and xenotime also can be found in primary deposits but are recovered principally from heavy-mineral placers that are mined for titanium or tin. Each of these minerals has a different composition of the 15 rare-earth elements. World resources of economically exploitable rare-earth oxides (REO) are estimated at 93.4 million metric tons in place, composed of 93 percent in primary deposits and 7 percent in placers. The average mineral composition is 83 percent bastnaesite, 13 percent monazite, and 4 percent of 10 other minerals. Annual global production is about 67,000 metric tons of which 41 percent is from placers and 59 percent is from primary deposits; mining methods consist of open pits (94 percent) and dredging (6 percent). This output could be doubled if the operations that do not currently recover rare earths would do so. Resources are more than sufficient to meet the demand for the predictable future. About 52 percent of the world's REO resources are located in China. Ranking of other countries is as follows: Namibia (22 percent), the United States (15 percent), Australia (6 percent), and India (3 percent); the remainder is in several other countries. Conversely, 38 percent of the production is in China, 33 percent in the United States, 12 percent in Australia, and 5 percent each in Malaysia and India. Several other countries, including Brazil, Canada, South Africa, Sri Lanka, and Thailand, make up the remainder. Markets for rare earths are mainly in the metallurgical, magnet, ceramic, electronic, chemical, and optical industries. Rare earths improve the physical and rolling properties of iron and steel and add corrosion resistance and strength to structural members at high temperatures. Samarium and neodymium are used in lightweight, powerful magnets for electric motors. Cerium and yttrium increase the

  16. Characterization of Rare Earth Element Minerals in Coal Utilization Byproducts

    DOE Office of Scientific and Technical Information (OSTI.GOV)

    Montross, Scott N.; Verba, Circe A.; Collins, Keith

    realizing the occurrence of REE mineral phases in CUB and allowed us to calculate structural and volumetric estimates of REE. Collectively, the rock and coal ash samples contained minerals such as quartz, kaolinite, muscovite/illite, iron oxide (as hematite or magnetite), mullite, and clinochlore. Trace minerals included pyrite, zircon, siderite, rutile, diopside, foresterite, gypsum, and barite. We identified REE phosphate minerals monazite (Ce,La,Nd,Th)(PO 4,SiO 4), xenotime (YPO 4,SiO 4), and apatite (Ca 5(PO 4) 3(F,Cl,OH) via SEM and electron microprobe analysis: these materials generally occurred as 1-10 μm-long crystals in the rock and ash samples. As has been shown in other studies, amorphous material-aluminosilicate glass or iron oxyhydroxide-are the major components of coal fly and bottom ash. Trace amounts of amorphous calcium oxide and mixed element (e.g., Al-Si-Ca-Fe) slag are also present. Quartz, mullite, hematite, and magnetite are the crystalline phases present. We found that REEs are present as monomineralic grains dispersed within the ash, as well as fused to or encapsulated by amorphous aluminosilicate glass particles. Monazite and xenotime have relatively high melting points (>1800 °C) compared to typical combustion temperatures; our observations indicate that the REE-phosphates, which presumably contribute a large percentage of REE to the bulk ash REE pool, as measured by mass spectroscopy, are largely unaltered by the combustion. Our study shows that conventional coal combustion processes sequester REE minerals into aluminosilicate glass phases, which presents a new engineering challenge for extracting REE from coal ash. The characterization work summarized in this report provides a semi-quantitative assessments of REE in coal-containing rock and CUB. The data we obtained from 2- and 3-D imaging, elemental mapping, volumetric estimates, and advanced high-resolution pixel classification successfully identified the different mineral phases present in

  17. Nanoforms: a new type of protein-associated mineralization

    NASA Astrophysics Data System (ADS)

    Vali, Hojatollah; McKee, Marc D.; Çiftçioglu, Neva; Sears, S. Kelly; Plows, Fiona L.; Chevet, Eric; Ghiabi, Pegah; Plavsic, Marc; Kajander, E. Olavi; Zare, Richard N.

    2001-01-01

    Controversy surrounds the interpretation of various nano-phenomena as being living organisms. Incubation of fetal bovine serum under standard cell culture conditions results in the formation of free entities in solution, here referred to as nanoforms. These nanoforms, when examined by transmission electron microscopy, have a distinct ovoid morphology ranging in size from tens to hundreds of nanometers. They are composed of hydroxyapatite and proteins and constitute a novel form of protein-associated mineralization. No detectable cell structure resembling bacteria is apparent. However, immunodetection of the proteins associated with the nanoforms, by two specific monoclonal antibodies, suggests a possible biogenic origin. The significance of nanoforms for the recognition of biological activity in ancient geological systems is discussed. The mode of mineralization in nanoforms is also compared to matrix-mediated calcification in vertebrates.

  18. An in situ FTIR step-scan photoacoustic investigation of kerogen and minerals in oil shale.

    PubMed

    Alstadt, Kristin N; Katti, Dinesh R; Katti, Kalpana S

    2012-04-01

    Step-scan photoacoustic infrared spectroscopy experiments were performed on Green River oil shale samples obtained from the Piceance Basin located in Colorado, USA. We have investigated the molecular nature of light and dark colored areas of the oil shale core using FTIR photoacoustic step-scan spectroscopy. This technique provided us with the means to analyze the oil shale in its original in situ form with the kerogen-mineral interactions intact. All vibrational bands characteristic of kerogen were found in the dark and light colored oil shale samples confirming that kerogen is present throughout the depth of the core. Depth profiling experiments indicated that there are changes between layers in the oil shale molecular structure at a length scale of micron. Comparisons of spectra from the light and dark colored oil shale core samples suggest that the light colored regions have high kerogen content, with spectra similar to that from isolated kerogen, whereas, the dark colored areas contain more mineral components which include clay minerals, dolomite, calcite, and pyrite. The mineral components of the oil shale are important in understanding how the kerogen is "trapped" in the oil shale. Comparing in situ kerogen spectra with spectra from isolated kerogen indicate significant band shifts suggesting important nonbonded molecular interactions between the kerogen and minerals. Copyright © 2011 Elsevier B.V. All rights reserved.

  19. Osteogenic differentiation of human mesenchymal stem cells in mineralized alginate matrices.

    PubMed

    Westhrin, Marita; Xie, Minli; Olderøy, Magnus Ø; Sikorski, Pawel; Strand, Berit L; Standal, Therese

    2015-01-01

    Mineralized biomaterials are promising for use in bone tissue engineering. Culturing osteogenic cells in such materials will potentially generate biological bone grafts that may even further augment bone healing. Here, we studied osteogenic differentiation of human mesenchymal stem cells (MSC) in an alginate hydrogel system where the cells were co-immobilized with alkaline phosphatase (ALP) for gradual mineralization of the microenvironment. MSC were embedded in unmodified alginate beads and alginate beads mineralized with ALP to generate a polymer/hydroxyapatite scaffold mimicking the composition of bone. The initial scaffold mineralization induced further mineralization of the beads with nanosized particles, and scanning electron micrographs demonstrated presence of collagen in the mineralized and unmineralized alginate beads cultured in osteogenic medium. Cells in both types of beads sustained high viability and metabolic activity for the duration of the study (21 days) as evaluated by live/dead staining and alamar blue assay. MSC in beads induced to differentiate in osteogenic direction expressed higher mRNA levels of osteoblast-specific genes (RUNX2, COL1AI, SP7, BGLAP) than MSC in traditional cell cultures. Furthermore, cells differentiated in beads expressed both sclerostin (SOST) and dental matrix protein-1 (DMP1), markers for late osteoblasts/osteocytes. In conclusion, Both ALP-modified and unmodified alginate beads provide an environment that enhance osteogenic differentiation compared with traditional 2D culture. Also, the ALP-modified alginate beads showed profound mineralization and thus have the potential to serve as a bone substitute in tissue engineering.

  20. Osteogenic Differentiation of Human Mesenchymal Stem Cells in Mineralized Alginate Matrices

    PubMed Central

    Westhrin, Marita; Xie, Minli; Olderøy, Magnus Ø.; Sikorski, Pawel

    2015-01-01

    Mineralized biomaterials are promising for use in bone tissue engineering. Culturing osteogenic cells in such materials will potentially generate biological bone grafts that may even further augment bone healing. Here, we studied osteogenic differentiation of human mesenchymal stem cells (MSC) in an alginate hydrogel system where the cells were co-immobilized with alkaline phosphatase (ALP) for gradual mineralization of the microenvironment. MSC were embedded in unmodified alginate beads and alginate beads mineralized with ALP to generate a polymer/hydroxyapatite scaffold mimicking the composition of bone. The initial scaffold mineralization induced further mineralization of the beads with nanosized particles, and scanning electron micrographs demonstrated presence of collagen in the mineralized and unmineralized alginate beads cultured in osteogenic medium. Cells in both types of beads sustained high viability and metabolic activity for the duration of the study (21 days) as evaluated by live/dead staining and alamar blue assay. MSC in beads induced to differentiate in osteogenic direction expressed higher mRNA levels of osteoblast-specific genes (RUNX2, COL1AI, SP7, BGLAP) than MSC in traditional cell cultures. Furthermore, cells differentiated in beads expressed both sclerostin (SOST) and dental matrix protein-1 (DMP1), markers for late osteoblasts/osteocytes. In conclusion, Both ALP-modified and unmodified alginate beads provide an environment that enhance osteogenic differentiation compared with traditional 2D culture. Also, the ALP-modified alginate beads showed profound mineralization and thus have the potential to serve as a bone substitute in tissue engineering. PMID:25769043

  1. The contamination of Lake Superior with amphibole gangue minerals.

    PubMed

    Langer, A M; Maggiore, C M; Nicholson, W J; Rohl, A N; Rubin, I B; Selikoff, I J

    1979-01-01

    Iron ore called taconite is mined in the Biwabik Iron Formation in the Eastern Mesabi region of the Mesabi Range, in eastern Minnesota. After mining, ore is shipped to Silver Bay, Minnnesota for processing and wet magnetic extraction. Tailings from the process are dumped, as a slurry, into a man-made containment delta constructed in Lake Superior. Submicroscopic amphibole fibers and/or cleavage fragments, a component of the gangue, apparently escape from the delta at Silver Bay, and enter Lake Superior. These particles contaiminate the potable water supplies of municipalities drawing directly from the lake. One of the gangue minerals is the amphibole grunerite, whose asbestiform variety is called amosite. Major emphasis of this study was directed at identification of submicroscopic particle pollutants, based on morphology, structure and chemical composition. Quantitative determination of fibrous amphibole phases, present in a range of water samples, was undertaken. Transmission electron microscopy, selected area electron diffraction, and an electron microprobe technique was used for identification and enumeration and this information was compared with data sets determined from standards. Grunerite fiber and/or acicular cleavage fragments, in some instances indistinguishable from asbestiform grunerite, are present in the tailings, lake water and drinking water of a number of municipalities, a result of contamination of the lake at the Silver Bay milling operation. This amphibole is found in drinking water in concentrations which range from 0.6 to 2.8 X 10(6) fiber/liter. The risk to health, associated with direct ingestion of grunerite fiber is unknown and is extrapolated from the asbestiform grunerite (amosite) data base. The biological activity of other fibrous amphiboles observed, unrelated to any asbestiform silicate variety, is presently unknown and warrants investigation.

  2. Laboratory manual: mineral X-ray diffraction data retrieval/plot computer program

    USGS Publications Warehouse

    Hauff, Phoebe L.; VanTrump, George

    1976-01-01

    The Mineral X-Ray Diffraction Data Retrieval/Plot Computer Program--XRDPLT (VanTrump and Hauff, 1976a) is used to retrieve and plot mineral X-ray diffraction data. The program operates on a file of mineral powder diffraction data (VanTrump and Hauff, 1976b) which contains two-theta or 'd' values, and intensities, chemical formula, mineral name, identification number, and mineral group code. XRDPLT is a machine-independent Fortran program which operates in time-sharing mode on a DEC System i0 computer and the Gerber plotter (Evenden, 1974). The program prompts the user to respond from a time-sharing terminal in a conversational format with the required input information. The program offers two major options: retrieval only; retrieval and plot. The first option retrieves mineral names, formulas, and groups from the file by identification number, by the mineral group code (a classification by chemistry or structure), or by searches based on the formula components. For example, it enables the user to search for minerals by major groups (i.e., feldspars, micas, amphiboles, oxides, phosphates, carbonates) by elemental composition (i.e., Fe, Cu, AI, Zn), or by a combination of these (i.e., all copper-bearing arsenates). The second option retrieves as the first, but also plots the retrieved 2-theta and intensity values as diagrammatic X-ray powder patterns on mylar sheets or overlays. These plots can be made using scale combinations compatible with chart recorder diffractograms and 114.59 mm powder camera films. The overlays are then used to separate or sieve out unrelated minerals until unknowns are matched and identified.

  3. Sodium-bicarbonated mineral water decreases aldosterone levels without affecting urinary excretion of bone minerals.

    PubMed

    Schoppen, Stefanie; Pérez-Granados, Ana M; Carbajal, Angeles; Sarriá, Beatriz; Navas-Carretero, Santiago; Pilar Vaquero, M

    2008-06-01

    AIM To assess in healthy postmenopausal women the influence of consuming sodium-bicarbonated mineral water on postprandial evolution of serum aldosterone and urinary electrolyte excretion. Eighteen postmenopausal women consumed 500 ml of two sodium-bicarbonated mineral waters (sodium-bicarbonated mineral water 1 and sodium-bicarbonated mineral water 2) and a low-mineral water with a standard meal. Postprandial blood samples were taken at 60, 120, 240, 360 and 420 min and aldosterone concentrations were measured. Postprandial urinary minerals were determined. Urinary and total mineral excretion and urinary mineral concentrations did not differ except for sodium concentration, which was significantly higher with sodium-bicarbonated mineral water 1 than with low-mineral water (P = 0.005). There was a time effect (P = 0.003) on the aldosterone concentration. At 120 min, aldosterone concentrations were lower with sodium-bicarbonated mineral water 1 (P = 0.021) and sodium-bicarbonated mineral water 2 (P = 0.030) compared with low-mineral water. Drinking a sodium-rich bicarbonated mineral water with a meal increases urinary sodium concentration excretion without changes in the excretion of potassium and bone minerals.

  4. Identification of provenance rocks based on EPMA analyses of heavy minerals

    NASA Astrophysics Data System (ADS)

    Shimizu, M.; Sano, N.; Ueki, T.; Yonaga, Y.; Yasue, K. I.; Masakazu, N.

    2017-12-01

    Information on mountain building is significant in the field of geological disposal of high-level radioactive waste, because this affects long-term stability in groundwater flow system. Provenance analysis is one of effective approaches for understanding building process of mountains. Chemical compositions of heavy minerals, as well as their chronological data, can be an index for identification of provenance rocks. The accurate identification requires the measurement of as many grains as possible. In order to achieve an efficient provenance analysis, we developed a method for quick identification of heavy minerals using an Electron Probe Micro Analyzer (EPMA). In this method, heavy mineral grains extracted from a sample were aligned on a glass slide and mounted in a resin. Concentration of 28 elements was measured for 300-500 grains per sample using EPMA. To measure as many grains as possible, we prioritized swiftness of measurement over precision, configuring measurement time of about 3.5 minutes for each grain. Identification of heavy minerals was based on their chemical composition. We developed a Microsoft® Excel® spread sheet input criteria of mineral identification using a typical range of chemical compositions for each mineral. The grains of <80 wt.% or >110 wt.% total were rejected. The criteria of mineral identification were revised through the comparison between mineral identification by optical microscopy and chemical compositions of grains classified as "unknown minerals". Provenance rocks can be identified based on abundance ratio of identified minerals. If no significant difference of the abundance ratio was found among source rocks, chemical composition of specific minerals was used as another index. This method was applied to the sediments of some regions in Japan where provenance rocks had lithological variations but similar formation ages. Consequently, the provenance rocks were identified based on chemical compositions of heavy minerals

  5. Iron Sulfide Minerals Record Microbe-Mineral Interactions in Anoxic Environments

    NASA Astrophysics Data System (ADS)

    Picard, A.; Gartman, A.; Cosmidis, J.; Clarke, D. R.; Girguis, P. R.

    2017-12-01

    The precipitation of most minerals in low-temperature environments on Earth is directly or indirectly influenced by the presence of organic substances and/or microbial biomass. Notably, the influence of microorganisms on the formation of Mn and Fe oxides/oxyhydroxides at the surface of the Earth has been well characterized (Chan et al., 2011; Estes et al., 2017). However, an oxygenated atmosphere is a unique feature of planet Earth. It is therefore critical for the search of life on other planetary bodies to characterize microbe-mineral interactions that form in anoxic conditions. Here we explore the role of microorganisms on the formation of iron sulfide minerals, which form under anoxic conditions. On modern Earth, sulfate-reducing microorganisms (SRM) are the major source of dissolved sulfide in low-temperature sedimentary environments. We experimentally demonstrate that SRM play a role in the nucleation and growth of iron sulfide minerals by acting as organic templates. The physical characteristics of the resulting minerals are different from those formed under abiotic conditions. Moreover, upon forming, iron sulfide minerals become associated with organic carbon, producing a potential organo-mineral signature. We also evaluate how the presence of various organic substances affect the formation of abiotic minerals and how this could produce false biosignatures that could be mistaken as biogenic minerals. Chan, C.S., Fakra, S.C., Emerson, D., Fleming, E.J. and Edwards, K.J. (2011) Lithotrophic iron-oxidizing bacteria produce organic stalks to control mineral growth: implications for biosignature formation. Isme Journal 5, 717-727. Estes, E.R., Andeer, P.F., Nordlund, D., Wankel, S.D. and Hansel, C.M. (2017) Biogenic manganese oxides as reservoirs of organic carbon and proteins in terrestrial and marine environments. Geobiology 15, 158-172.

  6. Biologically enhanced mineral weathering: what does it look like, can we model it?

    NASA Astrophysics Data System (ADS)

    Schulz, M. S.; Lawrence, C. R.; Harden, J. W.; White, A. F.

    2011-12-01

    The interaction between plants and minerals in soils is hugely important and poorly understood as it relates to the fate of soil carbon. Plant roots, fungi and bacteria inhabit the mineral soil and work symbiotically to extract nutrients, generally through low molecular weight exudates (organic acids, extracelluar polysachrides (EPS), siderophores, etc.). Up to 60% of photosynthetic carbon is allocated below ground as roots and exudates, both being important carbon sources in soils. Some exudates accelerate mineral weathering. To test whether plant exudates are incorporated into poorly crystalline secondary mineral phases during precipitation, we are investigating the biologic-mineral interface. We sampled 5 marine terraces along a soil chronosequence (60 to 225 ka), near Santa Cruz, CA. The effects of the biologic interactions with mineral surfaces were characterized through the use of Scanning Electron Microscopy (SEM). Morphologically, mycorrhizal fungi were observed fully surrounding minerals, fungal hyphae were shown to tunnel into primary silicate minerals and we have observed direct hyphal attachment to mineral surfaces. Fungal tunneling was seen in all 5 soils by SEM. Additionally, specific surface area (using a nitrogen BET method) of primary minerals was measured to determine if the effects of mineral tunneling are quantifiable in older soils. Results suggest that fungal tunneling is more extensive in the primary minerals of older soils. We have also examined the influence of organic acids on primary mineral weathering during soil development using a geochemical reactive transport model (CrunchFlow). Addition of organic acids in our models of soil development at Santa Cruz result in decreased activity of Fe and Al in soil pore water, which subsequently alters the spatial extent of primary mineral weathering and kaolinite precipitation. Overall, our preliminary modeling results suggest biological processes may be an important but underrepresented aspect of

  7. Melt rock components in KREEPy breccia 15205: Petrography and mineral chemistry of KREEP basalts and quartz-normative mare basalts

    NASA Astrophysics Data System (ADS)

    Shervais, John W.; Vetter, Scott K.

    1993-05-01

    Many current models for the origin of lunar highland rocks feature as an essential component the assimilation of KREEPy material by primitive magmas parental to the Mg-rich suite and alkali suite plutonic rocks. Similar models have also been proposed for the origin of various mare basalt suites. However, any model which considers assimilation of KREEP an important petrologic process must sooner-or-later deal with the question: what is KREEP? Because pristine KREEP basalts are rare, and most known samples are small (e.g., 15382/15386), the geochemical variability of KREEP basalts is poorly known. Other KREEP compositions which are commonly used in these models include the hypothetical 'high-K KREEP' component of Warren and Wasson, which is derived from Apollo 14 soil data, and the 'superKREEP' quartz-monzodiorite 15405. Lunar breccia 15205 is a polymict regolith breccia that consists of approximately 20% KREEP basalt clasts and 20% quartz-normative basalt clasts in a KREEP-rich matrix. Bulk rock mixing calculations show that this sample comprises about 84% KREEP. The clasts range up to 1 cm in size, but most are considerably smaller. The primary aim is to characterize pristine KREEP basalts petrographically, to establish the range in chemical compositions of KREEP basalts, and to test models that were proposed for their origin. In addition, we may be able to extend the compositional range recognized in the quartz-normative basalt suite and cast some light on its origin as well. Preliminary whole rock geochemical data on the KREEP basalts are presented in a companion paper by M.M. Lindstrom and co-workers. Concentration is on petrography and mineral chemistry of these clasts, and the implications these data have for the origin of the different melt rock suites.

  8. Melt rock components in KREEPy breccia 15205: Petrography and mineral chemistry of KREEP basalts and quartz-normative mare basalts

    NASA Technical Reports Server (NTRS)

    Shervais, John W.; Vetter, Scott K.

    1993-01-01

    Many current models for the origin of lunar highland rocks feature as an essential component the assimilation of KREEPy material by primitive magmas parental to the Mg-rich suite and alkali suite plutonic rocks. Similar models have also been proposed for the origin of various mare basalt suites. However, any model which considers assimilation of KREEP an important petrologic process must sooner-or-later deal with the question: what is KREEP? Because pristine KREEP basalts are rare, and most known samples are small (e.g., 15382/15386), the geochemical variability of KREEP basalts is poorly known. Other KREEP compositions which are commonly used in these models include the hypothetical 'high-K KREEP' component of Warren and Wasson, which is derived from Apollo 14 soil data, and the 'superKREEP' quartz-monzodiorite 15405. Lunar breccia 15205 is a polymict regolith breccia that consists of approximately 20% KREEP basalt clasts and 20% quartz-normative basalt clasts in a KREEP-rich matrix. Bulk rock mixing calculations show that this sample comprises about 84% KREEP. The clasts range up to 1 cm in size, but most are considerably smaller. The primary aim is to characterize pristine KREEP basalts petrographically, to establish the range in chemical compositions of KREEP basalts, and to test models that were proposed for their origin. In addition, we may be able to extend the compositional range recognized in the quartz-normative basalt suite and cast some light on its origin as well. Preliminary whole rock geochemical data on the KREEP basalts are presented in a companion paper by M.M. Lindstrom and co-workers. Concentration is on petrography and mineral chemistry of these clasts, and the implications these data have for the origin of the different melt rock suites.

  9. Estimating mineral requirements of Nellore beef bulls fed with or without inorganic mineral supplementation and the influence on mineral balance.

    PubMed

    Zanetti, D; Godoi, L A; Estrada, M M; Engle, T E; Silva, B C; Alhadas, H M; Chizzotti, M L; Prados, L F; Rennó, L N; Valadares Filho, S C

    2017-04-01

    The objectives of this study were to quantify the mineral balance of Nellore cattle fed with and without Ca, P, and micromineral (MM) supplementation and to estimate the net and dietary mineral requirement for cattle. Nellore cattle ( = 51; 270.4 ± 36.6 kg initial BW and 8 mo age) were assigned to 1 of 3 groups: reference ( = 5), maintenance ( = 4), and performance ( = 42). The reference group was slaughtered prior to the experiment to estimate initial body composition. The maintenance group was used to collect values of animals at low gain and reduced mineral intake. The performance group was assigned to 1 of 6 treatments: sugarcane as the roughage source with a concentrate supplement composed of soybean meal and soybean hulls with and without Ca, P, and MM supplementation; sugarcane as the roughage source with a concentrate supplement composed of soybean meal and ground corn with and without Ca, P, and MM supplementation; and corn silage as the roughage source with a concentrate supplement composed of soybean meal and ground corn with and without Ca, P, and MM supplementation. Orthogonal contrasts were adopted to compare mineral intake, fecal and urinary excretion, and apparent retention among treatments. Maintenance requirements and true retention coefficients were generated with the aid of linear regression between mineral intake and mineral retention. Mineral composition of the body and gain requirements was assessed using nonlinear regression between body mineral content and mineral intake. Mineral intake and fecal and urinary excretion were measured. Intakes of Ca, P, S, Cu, Zn, Mn, Co, and Fe were reduced in the absence of Ca, P, and MM supplementation ( < 0.05). Fecal excretion of Ca, Cu, Zn, Mn, and Co was also reduced in treatments without supplementation ( < 0.01). Overall, excretion and apparent absorption and retention coefficients were reduced when minerals were not supplied ( < 0.05). The use of the true retention coefficient instead of the true

  10. Enhanced thermogenesis in rats by Panax ginseng, multivitamins and minerals

    NASA Astrophysics Data System (ADS)

    Kumar, Ratan; Grover, S. K.; Divekar, H. M.; Gupta, A. K.; Shyam, Radhey; Srivastava, K. K.

    1996-12-01

    Substances which enhance endurance for physical and mental work and increase non-specific resistance to stress during a prolonged stay in physiologically adverse habitats are called ‘adaptogens’. Panax ginseng is well known for its anti-stress and adaptogenic properties. In the present study, adaptogenic activity by the intake of a herbo-vitamin-mineral preparation (HVMP) containing P. ginseng and multivitamin-mineral preparation (MVMP) was evaluated using the cold-hypoxia-restrained (C-H-R) animal model. The aim was to determine whether the cold tolerance and recovery from acute hypothermia mediated by P. ginseng was modified by simultaneous intake of additional vitamins and minerals. Results suggest that the adaptogenic effect of HVMP was more or less the sum total of its two components P. ginseng and MVMP. In HVMP, P. ginseng was found to be effective for developing resistance to cooling and MVMP helped in stimulating faster recovery from acute hypothermia.

  11. Electromagnetic system for detection and localization of the miners caught by accident in mine

    NASA Astrophysics Data System (ADS)

    Pronenko, Vira; Dudkin, Fedir

    2016-04-01

    It is well known that the profession of a miner is one of the most dangerous in the world. Among the main causes of the people death in the underground coal mining enterprises is their untimely alerting of the accident, as well as the lack of information for the rescuers about the actual location of the miners after the accident. As world practice shows, the electromagnetic (EM) systems for the search and detection of people across a massive layer of rock are the most effective. Such systems are under development almost half a century in many countries dealing with mine industry. However, substantial progress related to the localization of personnel at a distance at least of 20-30 meters through the rock is not reached. In an emergency situation (failure or destruction of underground infrastructure), personnel search behind and beneath of obstruction should be provided urgently. But none of the standard technologies (RFID, DECT, WiFi, emitting cable), which use the stationary technical devices in mines, do not provide notification of people caught by accident location. The only technology that provides guaranteed delivery of messages about the accident to the mine personnel, regardless of their location and under any destruction in the mine, is low-frequency radio technology able to operate through the thickness of rocks. From the general theoretical considerations, it is clear that the miners localization system requires solving the inverse problem of the magnetic field source coordinates determining using the data of 3-component magnetic field measurements. A fundamentally new approach, based on the measurement of the magnetic field of the miner's responder beacon by two fixed and spaced three-component magnetic field receivers and solution of the inverse problem using the results of the magnetic field measurement, was proposed. As a result, the concept of the equipment for miners beacon search and localization implementation (MILES - miner's location emergency

  12. Hygroscopic properties of large aerosol particles using the example of aged Saharan mineral dust - a semi-automated electron microscopy approach

    NASA Astrophysics Data System (ADS)

    Hartmann, Markus; Heim, Lars-Oliver; Ebert, Martin; Weinbruch, Stephan; Kandler, Konrad

    2015-04-01

    Hygroscopic properties of large aerosol particles using the example of aged Saharan mineral dust - a semi-automated electron microscopy approach Markus Hartmann(1), Lars-Oliver Heim(2), Martin Ebert(1), Stephan Weinbruch(1), Konrad Kandler(1) The Saharan Aerosol Long-range Transport and Aerosol-Cloud-Interaction Experiment (SALTRACE) took place at Barbados from June 10 to July 15 2013. During this period, dust was frequently transported from Africa across the Atlantic Ocean toward the Caribbean. In this study, we investigate the atmospheric aging of the dust aerosol based on its hygroscopicity. Aerosol samples were collected ground-based at Ragged Point (13°9'54.4"N, 59°25'55.7"W) with a single round jet cascade impactor on nickel-substrates. The particles from the stage with a 50% efficiency cutoff size of 1 µm were analyzed with an Environmental Scanning Electron Microscope (ESEM) equipped with an energy-dispersive X-ray detector (EDX) and a cooling stage. In an initial automated run, information on particle size and chemical composition for elements heavier than carbon were gathered. Afterwards, electron microscope images of the same sample areas as before were taken during a stepwise increase of relative humidities (between 50 % and 92%), so that the hygroscopic growth of the droplets could be directly observed. The observed hygroscopic growth can be correlated to the chemical composition of the respective particles. For the automated analysis of several hundred images of droplets an image processing algorithm in Python was developed. The algorithm is based on histogram equalization and watershed segmentation. Since SEM images can only deliver two-dimensional information, but the hygroscopic growth factor usually refers to the volume of a drop, Atomic Force Microscopy (AFM) was used to derive an empirical function for the drop volume depending on the apparent drop diameter in the electron images. Aside from the mineral dust, composed of mostly silicates and

  13. ELECTRONIC COMPONENT COOLING ALTERNATIVES: COMPRESSED AIR AND LIQUID NITROGEN

    EPA Science Inventory

    The goal of this study was to evaluate topics used to troubleshoot circuit boards with known or suspected thermally intermittent components. Failure modes for thermally intermittent components are typically mechanical defects, such as cracks in solder paths or joints, or broken b...

  14. AuScope research infrastructure - supporting Australian mineral discovery

    NASA Astrophysics Data System (ADS)

    McInnes, B.; Rawling, T.

    2016-12-01

    Earth and geospatial scientists are heavy users of data products. When industry geologists access spatial data from the field and the exploration office they require data products that are discoverable, searchable, interoperable and attributed with robust metadata. Over the last decade AuScope has utilised NCRIS funding to provide a variety of data products including geophysical data (reflection and passive seismic, magnetotellurics and gravity), GIS layers from state and national geological survey organisations, hyperspectral core logging (National Virtual Core Library) and time-series geospatial data from GNSS and VLBI instruments - all delivered using AuScope GRID technologies based on the Spatial Information Services Stack (SiSS). Perhaps one of the best examples of collaboration to deliver data products to industry users is the National Mineral Library. Working with researchers at Curtin Universities John de Laeter Centre and ANDS, AuScope has also supported the development of a Laboratory Information Management System (LIMS). The project has produced an entirely new workflow, based around a TESCAN TIMA field emission scanning electron microscope, that allows metadata to be collected and recorded from the sample collection and preparation right through to data delivery and publication. This process has facilitated the scanning of a large stockpile of mineral samples from across Western Australia that will produce a state-wide Mineral Library, allowing mineral explorers to better understand the composition of critical rock outcrop samples from all over the state. This new NCRIS supported initiative provides a dataset that underpins both academic and applied research programs and is important for the economic future of Australia. Mining companies do a lot of heavy mineral analysis in research and development but, because there isn't a baseline for mineralogy across each state, it is difficult to have full confidence in the heavy mineral data. This creates an

  15. Using MicroFTIR to Map Mineral Distributions in Serpentinizing Systems

    NASA Astrophysics Data System (ADS)

    Johnson, A.; Kubo, M. D.; Cardace, D.

    2016-12-01

    Serpentinization, the water-rock reaction forming serpentine mineral assemblages from ultramafic precursors, can co-occur with the production of hydrogen, methane, and diverse organic compounds (McCollom and Seewald, 2013), evolving water appropriate for carbonate precipitation, including in ophiolite groundwater flow systems and travertine-producing seeps/springs. Serpentinization is regarded as a geologic process important to the sustainability of the deep biosphere (Schrenk et al., 2013) and the origin of life (Schulte et al., 2006). In this study, we manually polished wafers of ultramafic rocks/associated minerals (serpentinite, peridotite, pyroxenite, dunite; olivine, diopside, serpentine, magnetite), and travertine/constituent minerals (carbonate crusts; calcite, dolomite), and observed mineral boundaries and interfaces using µFTIR analysis in reflection mode. We used a Thermo Nicolet iS50 FTIR spectrometer coupled with a Continuum IR microscope to map minerals/boundaries. We identify, confirm, and document FTIR wavenumber regions linked to serpentinite- and travertine-associated minerals by referencing IR spectra (RRUFF) and aligning with x-ray diffraction. The ultramafic and carbonate samples are from the following field localities: McLaughlin Natural Reserve - a UC research reserve, Lower Lake, CA; Zambales, PH; Ontario, CA; Yellow Dog, MI; Taskesti, TK; Twin Sisters Range, WA; Sharon, MA; Klamath Mountains, CA; Dun Mountain, NZ; and Sussex County, NJ. Our goals are to provide comprehensive µFTIR characterization of mineral profiles important in serpentinites and related rocks, and evaluate the resolving power of µFTIR for the detection of mineral-encapsulated, residual organic compounds from biological activity. We report on µFTIR data for naturally occurring ultramafics and travertines and also estimate the limit of detection for cell membrane components in mineral matrices, impregnating increasing mass proportions of xanthan gum in a peridotite sand

  16. Analytical energy gradient for the two-component normalized elimination of the small component method

    NASA Astrophysics Data System (ADS)

    Zou, Wenli; Filatov, Michael; Cremer, Dieter

    2015-06-01

    The analytical gradient for the two-component Normalized Elimination of the Small Component (2c-NESC) method is presented. The 2c-NESC is a Dirac-exact method that employs the exact two-component one-electron Hamiltonian and thus leads to exact Dirac spin-orbit (SO) splittings for one-electron atoms. For many-electron atoms and molecules, the effect of the two-electron SO interaction is modeled by a screened nucleus potential using effective nuclear charges as proposed by Boettger [Phys. Rev. B 62, 7809 (2000)]. The effect of spin-orbit coupling (SOC) on molecular geometries is analyzed utilizing the properties of the frontier orbitals and calculated SO couplings. It is shown that bond lengths can either be lengthened or shortened under the impact of SOC where in the first case the influence of low lying excited states with occupied antibonding orbitals plays a role and in the second case the jj-coupling between occupied antibonding and unoccupied bonding orbitals dominates. In general, the effect of SOC on bond lengths is relatively small (≤5% of the scalar relativistic changes in the bond length). However, large effects are found for van der Waals complexes Hg2 and Cn2, which are due to the admixture of more bonding character to the highest occupied spinors.

  17. AN INVESTIGATION OF THE MINERAL IN DUCTILE AND BRITTLE CORTICAL MOUSE BONE

    PubMed Central

    Rodriguez-Florez, Naiara; Garcia-Tunon, Esther; Mukadam, Quresh; Saiz, Eduardo; Oldknow, Karla J.; Farquharson, Colin; Millán, José Luis; Boyde, Alan; Shefelbine, Sandra J.

    2015-01-01

    Bone is a strong and tough material composed of apatite mineral, organic matter and water. Changes in composition and organization of these building blocks affect bone’s mechanical integrity. Skeletal disorders often affect bone’s mineral phase, either by variations in the collagen or directly altering mineralization. The aim of the current study was to explore the differences in the mineral of brittle and ductile cortical bone at the mineral (nm) and tissue (µm) levels using two mouse phenotypes. Osteogenesis imperfecta murine (oim−/−) mice were used to model brittle bone; PHOSPHO1 mutants (Phospho1−/−) had ductile bone. They were compared to their respective wild-type controls. Femora were defatted and ground to powder to measure average mineral crystal size using X-ray diffraction (XRD), and to monitor the bulk mineral to matrix ratio via thermogravimetric analysis (TGA). XRD scans were run after TGA for phase identification, to assess the fractions of hydroxyapatite and β-tricalcium phosphate. Tibiae were embedded to measure elastic properties with nanoindentation and the extent of mineralization with backscattered electron microscopy (qbSEM). Interestingly, the mineral of brittle oim−/− and ductile Phospho1−/− bones had many similar characteristics. Both pathology models had smaller apatite crystals, lower mineral to matrix ratio, and showed more thermal conversion to β-tricalcium phosphate than their wild-types, indicating deviations from stoichiometric hydroxyapatite in the original mineral. The degree of mineralization of the bone matrix was different for each strain: oim−/− were hypermineralized, while Phospho1−/− were hypomineralized. However, alterations in the mineral were associated with reduced tissue elastic moduli in both pathologies. Results revealed that despite having extremely different whole bone mechanics, the mineral of oim−/− and Phospho1−/− has several similar trends at smaller length scales. This

  18. Defective Mineralization in X-Linked Hypophosphatemia Dental Pulp Cell Cultures.

    PubMed

    Coyac, B R; Hoac, B; Chafey, P; Falgayrac, G; Slimani, L; Rowe, P S; Penel, G; Linglart, A; McKee, M D; Chaussain, C; Bardet, C

    2018-02-01

    X-linked hypophosphatemia (XLH) is a skeletal disease caused by inactivating mutations in the PHEX gene. Mutated or absent PHEX protein/enzyme leads to a decreased serum phosphate level, which cause mineralization defects in the skeleton and teeth (osteomalacia/odontomalacia). It is not yet altogether clear whether these manifestations are caused solely by insufficient circulating phosphate availability for mineralization or also by a direct, local intrinsic effect caused by impaired PHEX activity. Here, we evaluated the local role of PHEX in a 3-dimensional model of extracellular matrix (ECM) mineralization. Dense collagen hydrogels were seeded either with human dental pulp cells from patients with characterized PHEX mutations or with sex- and age-matched healthy controls and cultured up to 24 d using osteogenic medium with standard phosphate concentration. Calcium quantification, micro-computed tomography, and histology with von Kossa staining for mineral showed significantly lower mineralization in XLH cell-seeded scaffolds, using nonparametric statistical tests. While apatitic mineralization was observed along collagen fibrils by electron microscopy in both groups, Raman microspectrometry indicated that XLH cells harboring the PHEX mutation produced less mineralized scaffolds having impaired mineral quality with less carbonate substitution and lower crystallinity. In the XLH cultures, immunoblotting revealed more abundant osteopontin (OPN), dentin matrix protein 1 (DMP1), and matrix extracellular phosphoglycoprotein (MEPE) than controls, as well as the presence of fragments of these proteins not found in controls, suggesting a role for PHEX in SIBLING protein degradation. Immunohistochemistry revealed altered OPN and DMP1 associated with an increased alkaline phosphatase staining in the XLH cultures. These results are consistent with impaired PHEX activity having local ECM effects in XLH. Future treatments for XLH should target both systemic and local

  19. U.S. Geological Survey Mineral Resources Program - Science Supporting Mineral Resource Stewardship

    USGS Publications Warehouse

    Kropschot, S.J.

    2007-01-01

    The United States is the world's largest user of mineral resources. We use them to build our homes and cities, fertilize our food crops, and create wealth that allows us to buy goods and services. Individuals rarely use nonfuel mineral resources in their natural state - we buy light bulbs, not the silica, soda ash, lime, coal, salt, tungsten, copper, nickel, molybdenum, iron, manganese, aluminum, and zinc used to convert electricity into light. The USGS Mineral Resources Program (MRP) is the sole Federal source of scientific information and unbiased research on nonfuel mineral potential, production, and consumption, as well as on the environmental effects of minerals. The MRP also provides baseline geochemical, geophysical, and mineral-deposit data used to understand environmental issues related to extraction and use of mineral resources. Understanding how minerals, water, plants, and organisms interact contributes to our understanding of the environment, which is essential for maintaining human and ecosystem health. To support creation of economic and national security policies in a global context, MRP collects and analyzes data on essential mineral commodities from around the world.

  20. Cytochrome bc1-cy Fusion Complexes Reveal the Distance Constraints for Functional Electron Transfer Between Photosynthesis Components*

    PubMed Central

    Lee, Dong-Woo; Öztürk, Yavuz; Osyczka, Artur; Cooley, Jason W.; Daldal, Fevzi

    2008-01-01

    Photosynthetic (Ps) growth of purple non-sulfur bacteria such as Rhodobacter capsulatus depends on the cyclic electron transfer (ET) between the ubihydroquinone (QH2): cytochrome (cyt) c oxidoreductases (cyt bc1 complex), and the photochemical reaction centers (RC), mediated by either a membrane-bound (cyt cy) or a freely diffusible (cyt c2) electron carrier. Previously, we constructed a functional cyt bc1-cy fusion complex that supported Ps growth solely relying on membrane-confined ET (Lee, D.-W., Ozturk, Y., Mamedova, A., Osyczka, A., Cooley, J. W., and Daldal, F. (2006) Biochim. Biophys. Acta1757 ,346 -35216781662). In this work, we further characterized this cyt bc1-cy fusion complex, and used its derivatives with shorter cyt cy linkers as “molecular rulers” to probe the distances separating the Ps components. Comparison of the physicochemical properties of both membrane-embedded and purified cyt bc1-cy fusion complexes established that these enzymes were matured and assembled properly. Light-activated, time-resolved kinetic spectroscopy analyses revealed that their variants with shorter cyt cy linkers exhibited fast, native-like ET rates to the RC via the cyt bc1. However, shortening the length of the cyt cy linker decreased drastically this electronic coupling between the cyt bc1-cy fusion complexes and the RC, thereby limiting Ps growth. The shortest and still functional cyt cy linker was about 45 amino acids long, showing that the minimal distance allowed between the cyt bc1-cy fusion complexes and the RC and their surrounding light harvesting proteins was very short. These findings support the notion that membrane-bound Ps components form large, active structural complexes that are “hardwired” for cyclic ET. PMID:18343816