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Sample records for iron kalpha emission

  1. Iron K$\\alpha$ emission in type-I and type-II Active Galactic Nuclei

    CERN Document Server

    Ricci, Claudio; Paltani, Stephane; Ichikawa, Kohei; Gandhi, Poshak; Awaki, Hisamitsu

    2014-01-01

    The narrow Fe K$\\alpha$ line is one of the main signatures of the reprocessing of X-ray radiation from the material surrounding supermassive black holes, and it has been found to be omnipresent in the X-ray spectra of active galactic nuclei (AGN). In this work we study the characteristics of the narrow Fe K$\\alpha$ line in different types of AGN. Using the results of a large Suzaku study we find that Seyfert 2s have on average lower Fe K$\\alpha$ luminosities than Seyfert 1s for the same 10-50 keV continuum luminosity. Simulating dummy Sy1s and Sy2s populations using physical torus models of X-ray reflected emission, we find that this difference can be explained by means of different average inclination angles with respect to the torus, as predicted by the unified model. Alternative explanations include differences in the intensities of Compton humps or in the photon index distributions. We show that the ratio between the flux of the broad and narrow Fe K$\\alpha$ line in the 6.35-6.45 keV range depends on the ...

  2. Optimization of cold K-alpha emission using copper foams

    Science.gov (United States)

    Hussein, Amina; Hager, Jonathan; Flippo, Kirk

    2015-11-01

    Experiments were conducted at the Trident Laser Facility to increase the conversion efficiency of short-pulse, copper K-alpha x-ray backlighter sources. New target designs using copper foams are in development to investigate the role of underdense/near-critical density targets on the optimization of cold K-alpha emission. K-alpha emission was measured using Highly Ordered Pyrolytic Graphic (HOPG) and imaged with a toroidally bent quartz crystal to determine uniformity, spatial resolution and conversion efficiency of the new designs. Results from this experiment will help inform the development of short-pulse Cu K-alpha back-lighters on facilities like Omega, OmegaEP and the NIF, with a particular emphasis on creating advanced narrow-band backlighter sources capable of producing strong signal to noise with high x-ray fluxes.

  3. The Seyfert 2 galaxy NGC 2110: hard X-ray emission observed by NuSTAR and variability of the iron K$\\alpha$ line

    CERN Document Server

    Marinucci, A; Bianchi, S; Lu, T N; Arevalo, P; Baloković, M; Ballantyne, D; Bauer, F E; Boggs, S E; Christensen, F E; Craig, W W; Gandhi, P; Hailey, C J; Harrison, F; Puccetti, S; Rivers, E; Walton, D J; Stern, D; Zhang, W

    2014-01-01

    We present NuSTAR observations of the bright Seyfert 2 galaxy NGC 2110 obtained in 2012, when the source was at the highest flux level ever observed, and in 2013, when the source was at a more typical flux level. We include archival observations from other X-ray satellites, namely XMM-Newton, Suzaku, BeppoSAX, Chandra and Swift. Simultaneous NuSTAR and Swift broad band spectra (in the 3-80 keV range) indicate a cutoff energy $E_{\\rm c}>210$ keV, with no detectable contribution from Compton reflection. NGC 2110 is one of the very few sources where no evidence for distant Compton thick scattering is found and, by using temporal information collected over more than a decade, we investigate variations of the iron K$\\alpha$ line on time scales of years. The Fe K$\\alpha$ line is likely the sum of two components: one constant (originating from distant Compton-thick material) and the other one variable and linearly correlated with the source flux (possibly arising from Compton-thin material much closer to the black h...

  4. The Seyfert 2 Galaxy NGC 2110: Hard X-Ray Emission Observed by NuStar and Variability of the Iron K-Alpha Line

    Science.gov (United States)

    Marinucci, A.; Matt, G.; Bianchi, S.; Lu, T. N.; Arevalo, P.; Balokovic, M.; Ballantyne, D.; Bauer, F. E.; Boggs, S. E.; Stern, D.; Zhang, William W.

    2014-01-01

    We present NuSTAR observations of the bright Seyfert 2 galaxy NGC 2110 obtained in 2012, when the source was at the highest flux level ever observed, and in 2013, when the source was at a more typical flux level. We include archival observations from other X-ray satellites, namely XMM-Newton, Suzaku, BeppoSAX, Chandra and Swift. Simultaneous NuSTAR and Swift broad band spectra (in the 3-80 keV range) indicate a cutoff energy E(sub c) greater than 210 keV, with no detectable contribution from Compton reflection. NGC 2110 is one of the very few sources where no evidence for distant Compton thick scattering is found and, by using temporal information collected over more than a decade, we investigate variations of the iron K(alpha) line on time scales of years. The Fe K alpha line is likely the sum of two components: one constant (originating from distant Compton-thick material) and the other one variable and linearly correlated with the source flux (possibly arising from Compton-thin material much closer to the black hole).

  5. Variable Iron K-alpha Lines in Seyfert 1 Galaxies

    CERN Document Server

    Weaver, K A; Yaqoob, T

    2001-01-01

    We find that variability of the iron K-alpha line is common in Seyfert 1 galaxies. Using data from the ASCA archive for objects that have been observed more than once during the mission, we study the time-averaged spectra from individual observations, thereby probing variability on timescales that range from days to years. Since the statistics of the data do not warrant searches for line variability in terms of a complex physical model, we use a a simple Gaussian to model the gross shape of the line, and then use the centroid energy, intensity and equivalent width as robust indicators of changes in the line profile. We find that ~70% of Seyfert 1s (ten out of fifteen) show variability in at least one of these parameters: the centroid energy, intensity, and equivalent width vary in six, four, and eight sources respectively. Due to the low S/N, limited sampling and time averaging, we consider these results to represent lower limits to the rate of incidence of variability. In most cases changes in the line do no...

  6. Iron K$\\alpha$ line of boson stars

    CERN Document Server

    Cao, Zheng; Zhou, Menglei; Bambi, Cosimo; Herdeiro, Carlos A R; Radu, Eugen

    2016-01-01

    The present paper is a sequel to our previous work [Y. Ni et al., JCAP 1607, 049 (2016)] in which we studied the iron K$\\alpha$ line expected in the reflection spectrum of Kerr black holes with scalar hair. These metrics are solutions of Einstein's gravity minimally coupled to a massive, complex scalar field. They form a continuous bridge between a subset of Kerr black holes and a family of rotating boson stars depending on one extra parameter, the dimensionless scalar hair parameter $q$, ranging from 0 (Kerr black holes) to 1 (boson stars). Here we study the limiting case $q=1$, corresponding to rotating boson stars. For comparison, spherical boson stars are also considered. We simulate observations with XIS/Suzaku. Using the fact that current observations are well fit by the Kerr solution and thus requiring that acceptable alternative compact objects must be compatible with a Kerr fit, we find that some boson star solutions are relatively easy to rule out as potential candidates to explain astrophysical bla...

  7. Special relativistic effects on the strength of the fluorescent $K\\alpha$ iron line from black hole accretion disks

    CERN Document Server

    Reynolds, C S

    1997-01-01

    The broad iron K$\\alpha$ emission line, commonly seen in the X-ray spectrum of Seyfert nuclei, is thought to originate when the inner accretion disk is illuminated by an active disk-corona. We show that relative motion between the disk and the X-ray emitting material can have an important influence on the observed equivalent width (EW) of this line via special relativistic aberration and Doppler effects. We suggest this may be relevant to understanding why the observed EW often exceeds the prediction of the standard X-ray reflection model. Several observational tests are suggested that could disentangle these special relativistic effects from iron abundance effects.

  8. Resonant Auger Destruction and Iron K-Alpha Spectra in Compact X-ray Sources

    OpenAIRE

    Liedahl, Duane A.

    2005-01-01

    We examine the effects of resonant Auger destruction in modifying the intensities and flux distributions of K-alpha spectra from iron L-shell ions. Applications include X-ray irradiated stellar winds in X-ray binaries and accretion disk atmospheres. Using detailed atomic models, we find that resonant Auger destruction is selective, in that only a subset of the emitted K-alpha lines is highly attenuated. We also show that that the local excitation conditions can have a dramatic effect on the K...

  9. Discovery of strong Iron K{\\alpha} emitting Compton thick quasars at z=2.5 and 2.9

    CERN Document Server

    Feruglio, C; Fiore, F; Alexander, D M; Piconcelli, E; Malacaria, C

    2011-01-01

    We report the detection of the 6.4 keV Iron K{\\alpha} emission line in two infrared-luminous, massive, star-forming BzK galaxies at z = 2.578 and z = 2.90 in the CDF-S. The Chandra 4 Ms spectra of BzK4892 and BzK8608 show a reflection dominated continuum with strong Iron lines, with rest-frame equivalent widths EW-2.3 keV and 1.2 keV, respectively, demonstrating Compton thick obscuration of the central AGN. For BzK8608 the line identification closely matches the existing photometric redshift derived from the stellar emission. We use the observed luminosities of the Iron K{\\alpha} line, of the rest-frame mid-IR continuum and of the UV rest-frame narrow emission lines to infer intrinsic L(2-10 keV)>1e44 erg/s, about 1.0-2.5 dex larger than the observed ones, hence confirming the presence of an absorber with N(H) > 1e24 cm-2. The two BzK galaxies have stellar masses of 5e10 M\\odot and, based on VLA 1.4 GHz and submm 870{\\mu}m observations, they appear to host vigorous starburst activity with SFR - 300-700 M\\odot...

  10. Discovery of Red-Skewed K_alpha iron line in Cyg X-2 with Suzaku

    CERN Document Server

    Shaposhnikov, Nikolai; Laurent, Philippe

    2009-01-01

    We report on the Suzaku observation of neutron star low-mass X-ray binary Cygnus X-2 which reveals a presence of the iron K_alpha emission line. The line profile shows a significant red wing. This discovery increases the number of neutron star sources where red-skewed iron lines were observed and strongly suggests that this phenomenon is common not only in black holes but also in other types of accreting compact objects. We examine the line profile in terms of models which attribute its production to the relativistic effects due to reflection of X-ray radiation from a cold accretion disk and also as a result of the line formation in the extended wind/outflow configuration. Both models are able to adequately represent the observed line profile. We consider the results of line modeling in the context of subsecond variability. While we were unable to conclusively disqualify one of the models, we find that the wind paradigm has several advantages over the relativistic disk reflection model.

  11. Broad K$\\alpha$ iron line from accretion disks around traversable wormholes

    CERN Document Server

    Bambi, Cosimo

    2013-01-01

    It has been proposed that the supermassive black hole candidates at the centers of galaxies might be wormholes formed in the early Universe and connecting our Universe with other sister Universes. The analysis of the profile of the relativistic K$\\alpha$ iron line is currently the only available approach to probe the spacetime geometry around these objects. In this paper, I compute the expected K$\\alpha$ iron line in some wormhole spacetimes and I compare the results with the line produced around Kerr black holes. The line produced in accretion disks around non-rotating or very slow-rotating wormholes is relatively similar to the one expected around Kerr black holes with mid or high value of spin parameter and current observations are still marginally compatible with the possibility that the supermassive black hole candidates in galactic nuclei are these objects. For wormholes with spin parameter $a_* \\gtrsim 0.02$, the associated K$\\alpha$ iron line is instead quite different from the one produced around Ker...

  12. SMM observations of K-alpha radiation from fluorescence of photospheric iron by solar flare X-rays

    Science.gov (United States)

    Parmar, A. N.; Culhane, J. L.; Rapley, C. G.; Wolfson, C. J.; Acton, L. W.; Phillips, K. J. H.; Dennis, B. R.

    1984-01-01

    High-resolution Fe K-alpha spectra near 1.94 A observed during solar flares with the Bent Crystal Spectrometer on the Solar Maximum Mission are presented. The evidence for two possible excitation mechanisms, electron impact and fluorescence, is examined. It is found that the fluorescence mechanism satisfactorily describes the results, while the observations do not support electron collisional excitation of the Fe K-alpha transitions in low ionization stages (II-XII) of iron. Using Bai's model of the fluorescent excitation process, the photospheric iron abundance relative to that of hydrogen is estimated to be 5-6 x 10 to the -5th. The mean height of the soft X-ray source producing the K-alpha fluorescence is calculated on the basis of this model for about 40 large flares. The solar K-alpha lines are found to be about 25 percent wider than those measured in the laboratory. Weak line features observed at wavelengths shorter than that of the K-alpha lines are discussed.

  13. Using k-alpha emission to determine fast electron spectra using the Hybrid code ZEPHYROS

    CERN Document Server

    White, Thomas; Gregori, Gianluca

    2014-01-01

    A high intensity laser-solid interaction invariably drives a non-thermal fast electron current through the target, however characterizing these fast electron distributions can prove difficult. An understanding of how these electrons propagate through dense materials is of fundamental interest and has applications relevant to fast ignition schemes and ion acceleration. Here, we utilize an upgraded version of the Hybrid code ZEPHYROS to demonstrate how the resulting k-alpha emission from such an interaction can be used as a diagnostic to obtain the characteristic temperature, divergence and total energy of the fast electron population.

  14. Discovery of the Red-Skewed K-alpha Iron Line in Cyg X-2 with Suzaku

    Science.gov (United States)

    Shaposhnikov, Nikolai; Titarchuk, Lev; Laurent, Philippe

    2008-01-01

    We report on the Suzaku observation of neutron star low-mass X-ray binary Cygnus X-2 which reveals strong iron K-alpha emission line. The line profile shows a prominent red wing extending down to 4 keV. This discovery increases the number of neutron star sources where red-skewed iron lines were observed and strongly suggests that this phenomenon is common not only in black holes but also in other types of compact objects. We examine the line profile by fitting it with the model which attributes its production to the relativistic effects due to disk reflection of X-ray radiation. We also apply an alternative model where the red wing is a result of down-scattering effect of the first order with respect to electron velocity in the wind outflow. Both models describe adequately the observed line profile. However, the X-ray variability in a state similar to that in the Suzaku observation which we establish by analysing RXTE observation favors the wind origin of the line formation.

  15. K$\\alpha$ iron line profile from accretion disks around regular and singular exotic compact objects

    CERN Document Server

    Bambi, Cosimo

    2013-01-01

    The nature of the super-massive black hole candidates in galactic nuclei can be tested by analyzing the profile of the K$\\alpha$ iron line observed in their X-ray spectrum. In this paper, we consider the possibility that the spacetime in the immediate vicinity of these objects may be described by some non vacuum exact solutions of Einstein's equations resulting as the end-state of gravitational collapse. The vacuum far away portion of the spacetime is described by the Schwarzschild metric, while the interior part may be either regular or have a naked singularity at the center. The iron line generated around this class of objects has specific features, which can be used to distinguish such objects from Kerr black holes. In particular, their iron line cannot have the characteristic low-energy tail of the line generated from accretion disks around fast-rotating Kerr black holes. We can thus conclude that the super-massive black hole candidates whose spin parameter has been estimated to be close to 1 assuming the...

  16. K-Alpha Emission Spectra From Non-Equilibrium Ionizing Plasmas

    Energy Technology Data Exchange (ETDEWEB)

    Jacobs, V L; Decaux, V; Beiersdorfer, P

    2004-12-16

    K{alpha} X-ray emission spectra from highly charged Fe ions have been theoretically predicted using a detailed and systematic spectral model. Account has been taken of the fundamental atomic radiative-emission processes associated with inner-shell electron collisional excitation and ionization, as well as dielectronic recombination. Particular emphasis has been directed at extreme non-equilibrium or transient-ionization conditions, which can occur in astrophysical and tokamak plasmas. Good agreement has been found in comparisons with spectral observations on the EBIT-II electron beam ion trap at the Lawrence Livermore National Laboratory. We have identified spectral features that can serve as diagnostics of the electron density, the line-formation mechanism, and the charge-state distribution.

  17. The iron $K_\\alpha$ lines as a tool for magnetic field estimations in non-flat accretion flows

    CERN Document Server

    Zakharov, A F; Bao, Y

    2004-01-01

    Observations of AGNs and microquasars by ASCA, RXTE, Chandra and XMM-Newton indicate the existence of broad X-ray emission lines of ionized heavy elements in their spectra. Such spectral lines were discovered also in X-ray spectra of neutron stars and X-ray afterglows of GRBs. Recently, Zakharov et al. (MNRAS, 2003, 342, 1325) described a procedure to estimate an upper limit of the magnetic fields in regions from which X-ray photons are emitted. The authors simulated typical profiles of the iron $K_\\alpha$ line in the presence of magnetic field and compared them with observational data in the framework of the widely accepted accretion disk model. Here we further consider typical Zeeman splitting in the framework of a model of non-flat accretion flows, which is a generalization of previous consideration into non-equatorial plane motion of particles emitting X-ray photons. Using perspective facilities of space borne instruments (e.g. Constellation-X mission) a better resolution of the blue peak structure of iro...

  18. Iron K$\\alpha$ line of Kerr black holes with scalar hair

    CERN Document Server

    Ni, Yueying; Cardenas-Avendano, Alejandro; Bambi, Cosimo; Herdeiro, Carlos A R; Radu, Eugen

    2016-01-01

    Recently, a family of hairy black holes in 4-dimensional Einstein gravity minimally coupled to a complex, massive scalar field was discovered (Herdeiro & Radu, 2014). Besides the mass $M$ and spin angular momentum $J$, these objects are characterized by a Noether charge $Q$, measuring the amount of scalar hair, which is not associated to a Gauss law and cannot be measured at spatial infinity. Introducing a dimensionless scalar hair parameter $q$, ranging from 0 to 1, we recover (a subset of) Kerr black holes for $q=0$ and a family of rotating boson stars for $q=1$. In the present paper, we explore the possibility of measuring $q$ for astrophysical black holes with current and future X-ray missions. We study the iron K$\\alpha$ line expected in the reflection spectrum of such hairy black holes and we simulate observations with Suzaku and eXTP. As a proof of concept we show, by analyzing a sample of hairy black holes, that current observations can already rule out a region in the space of solutions, because ...

  19. Discovery of Oxygen Kalpha X-ray Emission from the Rings of Saturn

    CERN Document Server

    Bhardwaj, A; Waite, J H; Gladstone, G R; Cravens, T E; Ford, P G; Bhardwaj, Anil; Elsner, Ronald F.; Cravens, Thomas E.; Ford, Peter G.

    2005-01-01

    Using the Advanced CCD Imaging Spectrometer (ACIS), the Chandra X-ray Observatory (CXO) observed the Saturnian system for one rotation of the planet (~37 ks) on 20 January, 2004, and again on 26-27 January, 2004. In this letter we report the detection of X-ray emission from the rings of Saturn. The X-ray spectrum from the rings is dominated by emission in a narrow (~130 eV wide) energy band centered on the atomic oxygen K-alpha fluorescence line at 0.53 keV. The X-ray power emitted from the rings in the 0.49-0.62 keV band is 84 MW, which is about one-third of that emitted from Saturn disk in the photon energy range 0.24-2.0 keV. Our analysis also finds a clear detection of X-ray emission from the rings in the 0.49-0.62 keV band in an earlier (14-15 April, 2003) Chandra ACIS observation of Saturn. Fluorescent scattering of solar X-rays from oxygen atoms in the H2O icy ring material is the likely source mechanism for ring X-rays, consistent with the scenario of solar photo-production of a tenuous ring oxygen at...

  20. X-ray bumps, iron K-alpha lines, and X-ray suppression by obscuring tori in Seyfert galaxies

    Science.gov (United States)

    Krolik, Julian H.; Madau, Piero; Zycki, Piotr T.

    1994-01-01

    We investigate the X-ray spectral properties of unobscured type 1 and obscured type 2 Seyferts as predicted by the unified Seyfert scheme. We consider the reprocessing of X-ray photons by photoelectric absorption, iron fluorescence, and Compton downscattering in the obscuring tori surrounding these active nuclei, and compute by Monte Carlo methods the reprocessed spectra as a function of the viewing angle. Depending on the optical depth and shape of the torus, and on the viewing angle, the X-ray flux can be suppressed by substantial factors when our line of sight is obscured. We show that an immediate consequence of the existence of an obscuring thick torus is the production in the spectra of type 1 Seyfert galaxies of a bump in the continuum above 10-20 keV and an Fe K-alpha line with significant equivalent width. In those type 2 Seyferts for which the hard X-ray spectrum has been substantially suppressed, the equivalent width of the Fe K-alpha line in the transmitted spectrum can be very large.

  1. Constraining possible variations of the fine structure constant in strong gravitational fields with the K$\\alpha$ iron line

    CERN Document Server

    Bambi, Cosimo

    2013-01-01

    Extensions of general relativity and theories aiming at unifying gravity with the forces of the Standard Model are usually characterized by new degrees of freedom and violations of the Einstein Equivalence Principle. The search for time and/or space variations of fundamental parameters like the fine structure constant $\\alpha$ tests the assumption of Local Position Invariance. In this letter, I show that the analysis of the K$\\alpha$ iron line observed in the X-ray spectrum of black holes can probe $\\alpha$ in gravitational potentials relative to Earth of $\\Delta \\phi \\approx 0.1$. From the measurements of the black hole in Cygnus X-1 reported in the literature, one obtains $|\\Delta \\alpha / \\alpha| \\lesssim 0.01$.

  2. Resolving the Composite Fe K-alpha Emission Line in the Galactic Black Hole Cygnus X-1 with Chandra

    CERN Document Server

    Miller, J M; Wijnands, R; Remillard, R A; Wojdowski, P S; Schulz, N S; Matteo, T D; Marshall, H L; Canizares, C R; Pooley, D; Lewin, W H G

    2002-01-01

    We observed the Galactic black hole Cygnus X-1 with the Chandra High Energy Transmission Grating Spectrometer for 30 kiloseconds on 4 January, 2001. The source was in an intermediate state, with a flux that was approximately twice that commonly observed in its persistent low/hard state. Our best-fit model for the X-ray spectrum includes narrow Gaussian emission line (E = 6.415 +/- 0.007 keV, FWHM = 80 (+28, -19) eV, W = 16 (+3, -2) eV) and broad line (E = 5.82 (+0.06, -0.07) keV, FWHM = 1.9 (+0.5, -0.3) keV, W = 140 (+70, -40) eV) components, and a smeared edge at 7.3 +/- 0.2 keV (tau ~ 1.0). The broad line profile is not as strongly skewed as those observed in some Seyfert galaxies. We interpret these features in terms of an accretion disk with irradiation of the inner disk producing a broad Fe K-alpha emission line and edge, and irradiation of the outer disk producing a narrow Fe K-alpha emission line. The broad line is likely shaped predominantly by Doppler shifts and gravitational effects, and to a lesser...

  3. The dust sublimation radius as an outer envelope to the bulk of the narrow Fe Kalpha line emission in Type 1 AGN

    CERN Document Server

    Gandhi, Poshak; Kishimoto, Makoto

    2015-01-01

    The Fe Kalpha emission line is the most ubiquitous feature in the X-ray spectra of active galactic nuclei (AGN), but the origin of its narrow core remains uncertain. Here, we investigate the connection between the sizes of the Fe Kalpha core emission regions and the measured sizes of the dusty tori in 13 local Type 1 AGN. The observed Fe Kalpha emission radii (R_fe) are determined from spectrally resolved line widths in X-ray grating spectra, and the dust sublimation radii (R_dust) are measured either from optical/near-infrared reverberation time lags or from resolved near-infrared interferometric data. This direct comparison shows that the dust sublimation radius forms an outer envelope to the bulk of the Fe Kalpha emission. R_fe matches R_dust well in the AGN with the best constrained line widths currently. In a significant fraction of objects without a clear narrow line core, R_fe is similar to, or smaller than the radius of the optical broad line region. These facts place important constraints on the toru...

  4. The Broad Iron K-alpha line of Cygnus X-1 as Seen by XMM-Newton in the EPIC-pn Modified Timing Mode

    Science.gov (United States)

    Duro, Refiz; Dauser, Thomas; Wilms, Jorn; Pottschmidt, Katja; Nowak, Michael A.; Fritz, Sonja; Kendziorra, Eckhard; Kirsch, Marcus G. F.; Reynolds, Christopher S.; Staubert, Rudiger

    2011-01-01

    We present the analysis of the broadened, flourescent iron K(alpha) line in simultaneous XMM-Newton and RXTE data from the black hole Cygnus X-I. The XMM-Newton data were taken in a modified version of the Timing Mode of the EPIC-pn camera. In this mode the lower energy threshold of the instrument is increased to 2.8 keV to avoid telemetry drop outs due to the brightness of the source, while at the same time preserving the signal to noise ratio in the Fe K(alpha) band. We find that the best-fit spectrum consists of the sum of an exponentially cut-off power-law and relativistically smeared, ionized reflection. The shape of the broadened Fe K(alpha) feature is due to strong Compton broadening combined with relativistic broadening. Assuming a standard, thin accretion disk, the black hole is close to maximally rotating. Key words. X-rays: binaries - black hole physics - gravitation

  5. Relativistic Iron Line Emission from the Neutron Star Low-mass X-ray Binary 4U 1636-536

    OpenAIRE

    Pandel, Dirk; Kaaret, Philip; Corbel, Stephane

    2008-01-01

    We present an analysis of XMM-Newton and RXTE data from three observations of the neutron star LMXB 4U 1636-536. The X-ray spectra show clear evidence of a broad, asymmetric iron emission line extending over the energy range 4-9 keV. The line profile is consistent with relativistically broadened Fe K-alpha emission from the inner accretion disk. The Fe K-alpha line in 4U 1636-536 is considerably broader than the asymmetric iron lines recently found in other neutron star LMXBs, which indicates...

  6. A Relativistic Fe K-alpha Emission Line in the Intermediate Luminosity BeppoSAX Spectrum of the Galactic Microquasar V4641 Sgr

    CERN Document Server

    Miller, J M; in 't Zand, J J M; Reynolds, C S; Wijnands, R; Nowak, M A; Lewin, W H G

    2002-01-01

    Broad Fe K-alpha emission lines have recently been reported in a number of Galactic black holes. Such lines are useful accretion flow diagnostics because they may be produced at the inner accretion disk and shaped by relativistic effects, but in general they have only been observed at luminosities of L_X = 10^(37-38) erg/s in soft X-rays. The Galactic microquasar V4641 Sgr -- widely known for its 12.2 Crab (1.5-12 keV) outburst in 1999 September -- displayed low-level activity in 1999 March. BeppoSAX observed the source in this state and Fe K-alpha line emission was found (in 't Zand et al. 2000). In re-analyzing these data, we find strong evidence that the Fe K-alpha line profile is broadened. For the most likely values of the source distance and black hole mass measured by Orosz et al. (2001), our fits to the total spectrum indicate that the source was observed at a luminosity of L_X = 1.9 (+1.0, -0.8) * 10^(36) erg/s (2-10 keV), or L_(2-10)/L_(Eddington) = 1.8 (+0.9, -0.8) * 10^(-3). Advection-dominated ac...

  7. XMM-Newton Observation of Fe K(alpha) Emission from a BAL QSO: Mrk 231

    Science.gov (United States)

    Turner, T. J.; Kraemer, S. B.

    2003-01-01

    We present results from a 20 ksec XMM-Newton observation of Mrk 231. EPIC spectral data reveal strong line emission due to Fe K alpha, which has rarely been detected in this class, as BAL QSOs are very faint in the X-ray band. The line energy is consistent with an origin in neutral Fe. The width of the line is equivalent to a velocity dispersion approximately 18,000 kilometers per second and thus the line may be attributed to transmission and/or reflection from a distribution of emitting clouds. If, instead, the line originates in the accretion disk then the line strength and flat X-ray continuum support some contribution from a reflected component, although the data disfavor a model where the hard X-ray band is purely reflected X-rays. The line parameters are similar to those obtained for the Fe Ka line detected in another BAL QSO, H1413 + 117.

  8. Revealing the broad iron Kalpha line in Cygnus X-1 through simultaneous XMM-Newton, RXTE, and INTEGRAL observations

    CERN Document Server

    Duro, Refiz; Grinberg, Victoria; Miškovičová, Ivica; Rodriguez, Jérôme; Tomsick, John; Hanke, Manfred; Pottschmidt, Katja; Nowak, Michael A; Kreykenbohm, Sonja; Bel, Marion Cadolle; Bodaghee, Arash; Lohfink, Anne; Kendziorra, Eckhard; Kirsch, Marcus G F; Staubert, Rüdiger; Wilms, Jörn

    2016-01-01

    We report on the analysis of the broad Fe Kalpha line feature of Cygnus X-1 in the spectra of four simultaneous hard intermediate state observations made with the X-ray Multiple Mirror mission (XMM-Newton), the Rossi X-ray Timing Explorer (RXTE), and the International Gamma-Ray Astrophysics Laboratory (INTEGRAL). The high quality of the XMM-Newton data taken in the Modified Timing Mode of the EPIC-pn camera provides a great opportunity to investigate the broadened Fe Kalpha reflection line at 6.4keV with a very high signal to noise ratio. The 4-500keV energy range is used to constrain the underlying continuum and the reflection at higher energies. We first investigate the data by applying a phenomenological model that consists of the sum of an exponentially cutoff power law and relativistically smeared reflection. Additionally, we apply a more physical approach and model the irradiation of the accretion disk directly from the lamp post geometry. All four observations show consistent values for the black hole ...

  9. Testing the space-time geometry around black hole candidates with the analysis of the broad K$\\alpha$ iron line

    CERN Document Server

    Bambi, Cosimo

    2012-01-01

    Astrophysical black hole candidates are thought to be the Kerr black holes predicted by General Relativity, but there is not yet a clear evidence that the geometry of the space-time around these objects is really described by the Kerr metric. In order to confirm the Kerr black hole hypothesis, we have to observe strong gravity features and check they are in agreement with the ones predicted by General Relativity. In this paper, I study what kind of information can be extracted by analyzing the broad K$\\alpha$ iron line, which is often seen in the X-ray spectrum of both stellar-mass and super-massive black hole candidates and whose shape is supposed to be strongly affected by the space-time geometry. I extend previous studies in the literature. It turns out that there is a strong degeneracy between the spin parameter and the deformation parameter; that is, the line emitted around a Kerr black hole with a certain spin can be very similar to the one coming from the space-time around a non-Kerr object with a quit...

  10. K-shell Emission of Neutral Iron Line from Sgr B2 Excited by Subrelativistic Protons

    CERN Document Server

    Dogiel, Vladimir; Koyama, Katsuji; Nobukawa, Masayoshi; Cheng, Kwong-Sang

    2011-01-01

    We investigated the emission of K$\\alpha$ iron line from the massive molecular clouds in the Galactic center (GC). We assume that at present the total flux of this emission consists of time variable component generated by primary X-ray photons ejected by Sagittarius A$^\\ast$ (Sgr A$^\\ast$) in the past and a relatively weak quasi-stationary component excited by impact of protons which were generated by star accretion onto the central black hole. The level of background emission was estimated from a rise of the 6.4 keV line intensity in the direction of several molecular clouds, that we interpreted as a stage when the X-ray front ejected by Sgr A$^\\ast$ entered into these clouds. The 6.4 keV emission before this intensity jump we interpreted as emission generated by subrelativistic cosmic rays there. The cross-section of K$\\alpha$ vacancies produced by protons differs from that of electrons or X-rays. Therefore, we expect that this processes can be distinguished from the analysis of the equivalent width of the ...

  11. K(alpha) x-ray emission characterization of 100 Hz, 15 mJ femtosecond laser system with high contrast ratio.

    Science.gov (United States)

    Fourmaux, S; Serbanescu, C; Kincaid, R E; Krol, A; Kieffer, J C

    2008-12-12

    We report K(alpha) x-ray production with a high energy (110 mJ per pulse at 800 nm before compression/15 mJ at 400 nm after compression), high repetition rate (100 Hz), and high pulse contrast (better than 10(-9) at 400 nm) laser system. To develop laser-based x-ray sources for biomedical imaging requires to use high-energy and high-power ultra-fast laser system where compression is achieved under vacuum. Using this type of laser system, we demonstrate long-term stability of the x-ray yield, conversion efficiency higher than 1.5 x 10(-5) with a Mo target, and the x-ray spot size close to the optical focal spot. This high-repetition K(alpha) x-ray source can be very useful for x-ray phase-contrast imaging.

  12. CONTROLLING ODOROUS EMISSIONS FROM IRON FOUNDRIES

    Science.gov (United States)

    The report discusses the control of odorous emissions from iron foundries. he main process sources of odors in iron foundries are mold and core making, casting, and sand shakeout. he odors are usually caused by chemicals, which may be present as binders and other additives to the...

  13. Relativistic Iron K Emission and absorption in the Seyfert 1.9 galaxy MCG-5-23-16

    CERN Document Server

    Braito, V; Dewangan, G C; George, I; Griffiths, R E; Markowitz, A; Nandra, K; Porquet, D; Ptak, A; Turner, T J; Yaqoob, T; Weaver, K

    2007-01-01

    We present the results of the simultaneous deep XMM and Chandra observations of the bright Seyfert 1.9 galaxy MCG-5-23-16, which is thought to have one of the best known examples of a relativistically broadened iron K-alpha line. The time averaged spectral analysis shows that the iron K-shell complex is best modeled with an unresolved narrow emission component (FWHM < 5000 km/s, EW ~ 60 eV) plus a broad component. This latter component has FWHM ~ 44000 km/s and EW ~ 50 eV. Its profile is well described by an emission line originating from an accretion disk viewed with an inclination angle ~ 40^\\circ and with the emission arising from within a few tens of gravitational radii of the central black hole. The time-resolved spectral analysis of the XMM EPIC-pn spectrum shows that both the narrow and broad components of the Fe K emission line appear to be constant in time within the errors. We detected a narrow sporadic absorption line at 7.7 keV which appears to be variable on a time-scale of 20 ksec. If associa...

  14. X-ray resonant photoexcitation: line widths and energies of K{\\alpha} transitions in highly charged Fe ions

    CERN Document Server

    Rudolph, J K; Epp, S W; Steinbrügge, R; Beilmann, C; Brown, G V; Eberle, S; Graf, A; Harman, Z; Hell, N; Leutenegger, M; Müller, A; Schlage, K; Wille, H -C; Yavas, H; Ullrich, J; López-Urrutia, J R Crespo

    2013-01-01

    Photoabsorption by and fluorescence of the K{\\alpha} transitions in highly charged iron ions are essential mechanisms for X-ray radiation transfer in astrophysical environments. We study photoabsorption due to the main K{\\alpha} transitions in highly charged iron ions from heliumlike to fluorinelike (Fe 24+...17+) using monochromatic X-rays around 6.6 keV at the PETRA III synchrotron photon source. Natural linewidths were determined with hitherto unattained accuracy. The observed transitions are of particular interest for the understanding of photoexcited plasmas found in X-ray binaries and active galactic nuclei.

  15. Fe K$\\alpha$ Profiles from Simulations of Accreting Black Holes

    CERN Document Server

    Kinch, Brooks E; Kallman, Timothy R; Krolik, Julian H

    2016-01-01

    We present first results from a new technique for the prediction of Fe K$\\alpha$ profiles directly from general relativistic magnetohydrodynamic (GRMHD) simulations. Data from a GRMHD simulation are processed by a Monte Carlo global radiation transport code, which determines the X-ray flux irradiating the disk surface and the coronal electron temperature self-consistently. With that irradiating flux and the disk's density structure drawn from the simulation, we determine the reprocessed Fe K$\\alpha$ emission from photoionization equilibrium and solution of the radiation transfer equation. We produce maps of the surface brightness of Fe K$\\alpha$ emission over the disk surface, which---for our example of a $10 M_\\odot$, Schwarzschild black hole accreting at $1\\%$ the Eddington value---rises steeply one gravitational radius outside the radius of the innermost stable circular orbit and then falls $\\propto r^{-2}$ at larger radii. We explain these features of the Fe K$\\alpha$ radial surface brightness profile as ...

  16. Iron Features in the XMM-Newton spectrum of NGC 4151

    CERN Document Server

    Schurch, N J; Griffiths, R E; Ptak, A F

    2002-01-01

    We present a detailed analysis of the hard X-ray (>2.5 keV) EPIC spectra from the first observations of NGC 4151 made by XMM-Newton. We fit the spectra with a model consisting of a power-law continuum modified by line-of-sight absorption (arising in both partially photoionized and neutral gas) plus additional iron-K emission and absorption features. This model provides an excellent overall fit to the EPIC spectra. The iron K-alpha line is well modelled as a narrow Gaussian component. In contrast to several earlier studies based on data from ASCA, a relativistically broadened iron K-alpha emission feature is not required by the XMM-Newton data. The upper limit on the flux contained in any additional broad line is ~8% of that in the narrow line. The measured intrinsic line width (sigma =32+_7 eV) may be ascribed to (i) the doublet nature of the iron K-alpha line and (ii) emission from low ionization states of iron, ranging from neutral up to ~FeXVII. The additional iron absorption edge arises in cool material a...

  17. Simulations of the Fe K-alpha Energy Spectra from Gravitationally Microlensed Quasars

    CERN Document Server

    Krawczynski, Henric

    2016-01-01

    Chartas et al. (2012, 2016a,b) reported the discovery of multiple and energy variable peaks of the Fe K-alpha emission from the gravitationally lensed quasar RX J1131-1231. The authors explain the observations by the microlensing (produced by the stars of the lensing galaxy) of the emission from different regions of the accretion disk with different Doppler and gravitational frequency shifts. In this paper, we combine detailed simulations of the Fe K-alpha emission of the accretion disk in the Kerr spacetime of the black hole with calculations of the effect of gravitational microlensing on the observed energy spectra. The simulations give multiply peaked energy spectra similar to the observed ones. We explore the dependence of the spectral characteristics on black hole spin, accretion disk inclination, corona height, and microlensing amplification factor, and show that the measurements can be used to constrain these parameters. The detailed simulations described in this paper confirm the earlier constraints o...

  18. A redshifted Fe K$\\alpha$ line from the unusual gamma-ray source PMN J1603-4904

    CERN Document Server

    Müller, C; Dauser, T; Kreikenbohm, A; Beuchert, T; Kadler, M; Ojha, R; Wilms, J; Böck, M; Carpenter, B; Markowitz, A; McConville, W; Pottschmidt, K; Stawarz, L; Taylor, G B

    2015-01-01

    Multiwavelength observations have revealed the highly unusual properties of the gamma-ray source PMN J1603-4904, which are difficult to reconcile with any other well established gamma-ray source class. The object is either a very atypical blazar or compact jet source seen at a larger angle to the line of sight. In order to determine the physical origin of the high-energy emission processes in PMN J1603-4904, we study the X-ray spectrum in detail. We performed quasi-simultaneous X-ray observations with XMM-Newton and Suzaku in 2013 September, resulting in the first high signal-to-noise X-ray spectrum of this source. The 2-10 keV X-ray spectrum can be well described by an absorbed power law with an emission line at 5.44$\\pm$0.05 keV (observed frame). Interpreting this feature as a K{\\alpha} line from neutral iron, we determine the redshift of PMN J1603-4904 to be z=0.18$\\pm$0.01, corresponding to a luminosity distance of 872$\\pm$54 Mpc. The detection of a redshifted X-ray emission line further challenges the or...

  19. A K-alpha x-ray source using high energy and high repetition rate laser system for phase contrast imaging.

    Science.gov (United States)

    Serbanescu, Cristina; Fourmaux, Sylvain; Kieffer, Jean-Claude; Kincaid, Russell; Krol, Andrzej

    2009-01-01

    K-alpha x-ray sources from laser produced plasmas provide completely new possibilities for x-ray phase-contrast imaging applications. By tightly focusing intense femtosecond laser pulses onto a solid target K-alpha x-ray pulses are generated through the interaction of energetic electrons created in the plasma with the bulk target. In this paper, we present a continuous and efficient Mo K-alpha x-ray source produced by a femtosecond laser system operating at 100 Hz repetition rate with maximum pulse energy of 110 mJ before compression. The source has an x-ray conversion efficiency of greater than 10(-5) into K-alpha line emission. In preparation for phase contrast imaging applications, the size of the resultant K-alpha x-ray emission spot has been also characterized. The source exhibits sufficient spatial coherence to observe phase contrast. We observe a relatively small broadening of the K-alpha source size compared to the size of the laser beam itself. Detailed characterization of the source including the x-ray spectrum and the x-ray average yield along with phase contrast images of test objects will be presented.

  20. Microlensing of the Fe K$\\alpha$ line and the X-ray continuum

    CERN Document Server

    Popovic, L C; Mediavilla, E; Zakharov, A F; Abajas, C; Muñoz, J A; Chartas, G

    2005-01-01

    The observed enhancement of the Fe K$\\alpha$ line in three gravitationally lensed QSOs (MG J0414+0534, QSO 2237+0305, H1413+117) is interpreted in terms of microlensing, even when equivalent X-ray continuum amplification is not observed. In order to interpret these observations, first we studied the effects of microlensing on quasars spectra, produced by straight fold caustic crossing over standard relativistic accretion disk. The disk emission was analyzed using the ray tracing method, considering Schwarzschild and Kerr metrics. When the emission is separated in two regions (an inner disk corresponding to the Fe K$\\alpha$ line and an outer annulus corresponding to the continuum, or vice-versa) we find microlensing events which enhance the Fe K$\\alpha$ line without noticeable amplification of the X-ray continuum, but only during a limited time interval. Continuum amplification is expected if a complete microlensing event is monitored. Second, we studied a more realistic case of amplification by caustic magnif...

  1. Suzaku Monitoring of the Iron K Emission Line in the Type 1 AGN NGC 5548

    CERN Document Server

    Liu, Yuan; McHardy, Ian M; Grupe, Dirk; Wilkes, Belinda J; Reeves, James; Brickhouse, Nancy; Krongold, Yair; Mathur, Smita; Minezaki, Takeo; Nicastro, Fabrizio; Yoshii, Yuzuru; Zhang, Shuang Nan

    2010-01-01

    We present 7 sequential weekly observations of NGC 5548 conducted in 2007 with the \\textit{Suzaku} X-ray Imaging Spectrometer (XIS) in the 0.2-12 keV band and Hard X-ray Detector (HXD) in 10-600 keV band. The iron K$\\alpha$ line is well detected in all seven observations and K$\\beta$ line is also detected in four observations. In this paper, we investigate the origin of the Fe K lines using both the width of the line and the reverberation mapping method. With the co-added XIS and HXD spectra, we identify Fe K$\\alpha$ and K$\\beta$ line at 6.396$_{-0.007}^{+0.009}$ keV and 7.08$_{-0.05}^{+0.05}$ keV, respectively. The width of line obtained from the co-added spectra is 38$_{-18}^{+16}$ eV ($\\textrm{FWHM}=4200_{-2000}^{+1800}$ km/s) which corresponds to a radius of 20$_{-10}^{+50}$ light days, for the virial production of $1.220\\times10^7$ M$_{\\odot}$ in NCG 5548. To quantitatively investigate the origin of the narrow Fe line by the reverberation mapping method, we compare the observed light curves of Fe K$\\alph...

  2. Atmospheric emission of polychlorinated naphthalenes from iron ore sintering processes.

    Science.gov (United States)

    Liu, Guorui; Zheng, Minghui; Du, Bing; Nie, Zhiqiang; Zhang, Bing; Liu, Wenbin; Li, Cheng; Hu, Jicheng

    2012-10-01

    Iron ore sintering processes constitute significant sources of dioxins, and studies have confirmed a close correlation between polychlorinated naphthalenes (PCNs) and dioxin formation. Thus, iron ore sintering processes are thought to be a potential source of PCNs, although intensive investigations on PCN emissions from sintering processes have not been carried out. Therefore, the aim of the present study was to qualify and quantify PCN emissions from nine sintering plants operating on different industrial scales. PCN concentrations ranged from 3 to 983 ng m(-3) (0.4-23.3 pg TEQ(PCN) m(-3)) and emission factors ranged from 14 to 1749 μg t(-1) (0.5-41.5 ng TEQ(PCN) t(-1)), with a geometric mean of 84 μg t(-1) (2.1 ng TEQ(PCN) t(-1)). The estimated annual emission of PCNs from sintering processes in China was 1390 mg TEQ(PCN). These figures will assist in the development of a PCN emissions inventory. Regarding emission characteristics, PCNs mainly comprised low-chlorinated homologs. The ratios of several characteristic PCN congeners were also measured and compared with those from other sources. Taken together, these results may provide useful information for identifying the sources of PCNs produced by iron ore sintering processes. Copyright © 2012 Elsevier Ltd. All rights reserved.

  3. Net Emission Coefficients for Copper and Iron Plasmas

    Science.gov (United States)

    Kassubek, Frank; Zilberberg, Oded; Doiron, Charles

    2016-09-01

    Radiative heat transfer is an important mechanism for heat transport in electrical arcs, e.g. in electrical switchgear. An exact description of this phenomenon is important (i) for the energy balance of the arc itself, and (ii) for the estimate of the escaping radiation that leads to evaporation of polymer nozzles; the evaporated material and its flow have a strong effect on the arcs. For low voltage arcs, the plasma composition within the arc is dominated by the contact material. In the present study, we compare copper and iron. Especially, we discuss the calculation of absorption and emission spectra and their characterisation by net emission coefficients. The latter describe well the effective power balance at the centre of the arc. We show that in addition to the net emission coefficients, it is important to characterise the radiation that is emitted from the arc core.

  4. K-alpha X-rays from cosmic ray oxygen. [Detection and calculation of equilibrium charge fractions

    Science.gov (United States)

    Pravdo, S. H.; Boldt, E. A.

    1975-01-01

    Equilibrium charge fractions are calculated for subrelativistic cosmic ray oxygen ions in the interstellar medium. These are used to determine the expected flux of K-alpha rays arising from atomic processes for a number of different postulated interstellar oxygen spectra. Relating these results to the diffuse X-ray background measured at the appropriate energy level suggests an observable line feature. If the flux of low energy cosmic ray oxygen is sufficiently large, K-alpha X-ray line emission from these nuclei will comprise a significant fraction of the total diffuse flux at approximately 0.6 keV. A satellite borne detector with a resolution greater than 30 percent could observe this feature if the subrelativistic interstellar cosmic ray oxygen spectrum is as large as certain theoretical estimates expressed in the text.

  5. [Effects of temperature and heating time on armco iron spectral emissivity in atmospheric environment].

    Science.gov (United States)

    Yu, Kun; Wang, Wen-Bao; Zhang, Kai-Hua; Liu, Yu-Fang

    2014-09-01

    The spectral emissivity of pure iron at 1.55 μm was investigated systematically by using our self-designed reflective experimental apparatus based on the Kirchhoff's law, and the influences of temperature and heating time on the spectral emissivity of pure iron were also discussed. The experimental data showed that the spectral emissivity of pure iron increased with temperature rising and its peak value and valley value appeared at certain temperatures. By analyzing the emissivity model of metal with oxidation layer, the variation of the spectral emissivity of pure iron was illustrated. The influence of heating time on the spectral emissivity was different at different temperature. The research results will further enrich pure iron spectral emissivity data, and provide the experimental basis for its application in atmospheric environment.

  6. Design Parameter Studies of Emission-Based Iron Opacity Measurements

    Science.gov (United States)

    Martin, Madison E.; London, Richard A.; Goluoglu, Sedat; Whitley, Heather D.

    2016-10-01

    Opacity is a critical parameter in the transport of radiation in systems such as inertial confinement fusion capsules and stars. The resolution of current disagreements between solar models and helioseismological observations would benefit from experimental validation of theoretical opacity models. Short pulse lasers can be used to heat targets to higher temperatures and densities than long pulse lasers and pulsed power machines, thus potentially enabling access to x-ray emission spectra at conditions relevant to solar models. The radiation-hydrodynamic code HYDRA is used to investigate the effects of modifying laser energy, laser pulse length, and target dimensions on the plasma conditions, x-ray emission, and inferred opacity of a buried layer iron target. The accuracy of the opacity inference is sensitive to tamper emission and optical depth effects. An example design that reaches temperatures and densities relevant to the radiative zone of the sun while reducing optical depth and tamper emission effects will be discussed. This work was performed under the auspices of the U.S. Department of Energy by Lawrence Livermore National Laboratory under Contract DE-AC52-07NA27344. Lawrence Livermore National Security, LLC.

  7. Evidence for a relativistic iron line in GRS 1915+105

    CERN Document Server

    Martocchia, A; Karas, V; Belloni, T; Feroci, M

    2002-01-01

    We report on the discovery of a relativistic iron K\\alpha fluorescent emission line in the BeppoSAX spectrum of the microquasar GRS 1915+105, taken on April 19, 1998, when the line was unusually intense. The feature is broad and skewed, clearly indicating emission from the innermost regions of the accretion disc. The inner emitting orbit is larger than the innermost stable orbit, even in Schwarzschild metric: thus, a non-zero BH spin is not required by these data.

  8. Ultra-fast Measurements of Optically Induced Lattice Dynamics in LuMnO3 Using Aluminum K-alpha X-Ray Diffraction.

    Science.gov (United States)

    Workman, J.; Wark, J. S.

    2005-10-01

    An experiment to study the structural dynamics at the ultra-fast time scale in optically-pumped samples is presented. Measurements of lattice dynamics in LuMnO3 are presented and compared to calculations using dynamical diffraction theory modified for hexagonal crystal structure. Ultra-fast x-ray emission is used to measure Bragg peak shifts using diffraction and compared to calculations. Results are presented for optical pump energy densities of 8 and 20-mJ/cm^2. The experiment uses ˜150 mJ of a 100fs Ti:Sapphire laser to excite K-alpha x-ray emission in an aluminum wire with ˜1-2% split off for the material pump. The x-ray emission is relayed using a spherical Quartz crystal to the sample target. Plans for experiments using Cu K-alpha emission to probe Fe samples will also be described.

  9. Comparison of CO2 emission between COREX and blast furnace iron-making system.

    Science.gov (United States)

    Hu, Changqing; Han, Xiaowei; Li, Zhihong; Zhang, Chunxia

    2009-01-01

    Steel works faced increasing demand to minimize the emission of GHGs. The CO2 emissions of COREX and blast furnace iron-making system were compared. It is point out that COREX contribute little to CO2 emission reduction. Comparing to conventional blast furnace iron-making system, direct CO2 emissions of COREX is higher. Considering the credits of export gases for power generation, the total CO2 emission of COREX have advantages only when the COREX is joined with high-efficiency generating units which efficiency is greater than 45% and CO2 emission factor of the grid is higher than 0.9 kgCO2/kWh.

  10. Mercury mass flow in iron and steel production process and its implications for mercury emission control.

    Science.gov (United States)

    Wang, Fengyang; Wang, Shuxiao; Zhang, Lei; Yang, Hai; Gao, Wei; Wu, Qingru; Hao, Jiming

    2016-05-01

    The iron and steel production process is one of the predominant anthropogenic sources of atmospheric mercury emissions worldwide. In this study, field tests were conducted to study mercury emission characteristics and mass flows at two iron and steel plants in China. It was found that low-sulfur flue gas from sintering machines could contribute up to 41% of the total atmospheric mercury emissions, and desulfurization devices could remarkably help reduce the emissions. Coal gas burning accounted for 17%-49% of the total mercury emissions, and therefore the mercury control of coal gas burning, specifically for the power plant burning coal gas to generate electricity, was significantly important. The emissions from limestone and dolomite production and electric furnaces can contribute 29.3% and 4.2% of the total mercury emissions from iron and steel production. More attention should be paid to mercury emissions from these two processes. Blast furnace dust accounted for 27%-36% of the total mercury output for the whole iron and steel production process. The recycling of blast furnace dust could greatly increase the atmospheric mercury emissions and should not be conducted. The mercury emission factors for the coke oven, sintering machine and blast furnace were 0.039-0.047gHg/ton steel, and for the electric furnace it was 0.021gHg/ton steel. The predominant emission species was oxidized mercury, accounting for 59%-73% of total mercury emissions to air.

  11. Emission factors of the iron and steel sector for the emission reporting; Emissionsfaktoren zur Eisen- und Stahlindustrie fuer die Emissionsberichterstattung

    Energy Technology Data Exchange (ETDEWEB)

    Hensmann, Michael; Haardt, Sebastian; Ebert, Dominik [Betriebsforschungsinstitut VDEh-Institut fuer Angewandte Forschung GmbH, Duesseldorf (Germany)

    2012-10-15

    The German Umweltbundesamt (UBA) records emission factors of important groups of emitters of the iron- and steelmaking industry in a central database named ''Zentrales System Emissionen'' (ZSE) since 1990. This data is being used for calculations of emission inventories. The main purposes are the generation of forecasts, calculating emissions of other plants and the appraisal of potential measures for reduction of pollution. This makes it possible to identify and appraise future problems and measures. Because of steadily increasing requirements to data quality and quality assurance, it became necessary to update the ZSE with characteristical emission data in order to give a representative view of relevant stages in the iron- and steelmaking industry with respect to emissions. In 2008, the VDEh-Betriebsforschungsinstitut (BFI) was assigned to determine up-to-date emission factors for the following relevant stages in the iron- and steelmaking industry: - sintering plant - coking plant - blast furnace - steel making (differentiated between oxygen and electric steel making) - production of rolled steel Due to a wide diversity of data quality, a consecutive project to determine the corresponding uncertainty of the emission factors was integrated into the ongoing project. This is necessary to create reliable forecasts of emissions and to meet national and international duties of reporting. The project was supported by 18 companies of the German iron- and steelmaking industry. A total of 40 relevant sources of emissions were identified within the five stages of steelmaking and taken into consideration. The emission data for documenting organic and inorganic components of harmful gas, heavy metals and air borne dusts in the ZSE was taken from the reports of emissions 2008 of the supporting companies and made up for a total of 63 plants. Due to a wide variety of data quality the emissions of point sources and diffuse sources are treated separately. While

  12. On the equivalent width of the Fe K$\\alpha$ line produced by a dusty absorber in active galactic nuclei

    CERN Document Server

    Gohil, Raj

    2015-01-01

    Obscured AGNs provide an opportunity to study the material surrounding the central engine. Geometric and physical constraints on the absorber can be deduced from the reprocessed AGN emission. In particular, the obscuring gas may reprocess the nuclear X-ray emission producing a narrow Fe K$\\alpha$ line and a Compton reflection hump. In recent years, models of the X-ray reflection from an obscuring torus have been computed; however, although the reflecting gas may be dusty, the models do not yet take into account the effects of dust on the predicted spectrum. We study this problem by analyzing two sets of models, with and without the presence of dust, using the one dimensional photo-ionization code Cloudy. The calculations are performed for a range of column densities ($22 <{\\rm log}[N_H(\\rm cm^{-2})]< 24.5$ ) and hydrogen densities ( $6 <{\\rm log}[n_H(\\rm cm^{-3})]< 8$). The calculations show the presence of dust can enhance the Fe K$\\alpha$ equivalent width (EW) in the reflected spectrum by factor...

  13. The narrow Fe K$\\alpha$ line and the molecular torus in active galactic nuclei - an IR/X-ray view

    CERN Document Server

    Ricci, Claudio; Ichikawa, Kohei; Paltani, Stephane; Boissay, Rozenn; Gandhi, Poshak; Stalevski, Marko; Awaki, Hisamitsu

    2014-01-01

    The narrow component of the iron K$\\alpha$ is an almost ubiquitous feature in the X-ray spectra of active galactic nuclei (AGN) and is believed to originate in neutral material, possibly located in the molecular torus. This would imply a tight connection between the Fe K$\\alpha$ equivalent width (EW) and the physical properties of the torus. In a recent work we have shown that the decrease of the covering factor of the torus with the luminosity, as expected by luminosity-dependent unification models, would be able to explain the decrease of Fe K$\\alpha$ EW with the luminosity (i.e., the X-ray Baldwin effect). Recent developments in the study of the mid-IR (MIR) spectrum of AGN allow important parameters of the torus to be deduced, such as its covering factor ($f_{\\rm\\,obs}$) and equatorial column density ($N_{\\rm\\,H}^{\\rm\\,T}$), by applying clumpy torus models. Using XMM-Newton/EPIC observations of a sample of 24 type-I AGN, we investigate the relation between the physical parameters of the torus obtained by ...

  14. EMISSION FACTORS FOR IRON AND STEEL SOURCES: CRITERIA AND TOXIC POLLUTANTS

    Science.gov (United States)

    The report provides a comprehensive set of emission factors for sources of both criteria and toxic air pollutants in integrated iron and steel plants and specialty electric arc shops (minimills). Emission factors are identified for process sources, and process and open source fug...

  15. An Empirical Ultraviolet Template for Iron Emission in Quasars as Derived from I Zw 1

    DEFF Research Database (Denmark)

    Vestergaard, Marianne; Wilkes, B. J.

    2001-01-01

    contaminant in optical--UV spectra of AGNs. Its presence complicates and limits the accuracy of measurements of both strong and weak emission lines and the continuum emission, affecting studies of line and continuum interrelations, the ionization structure, and elemental abundances in AGNs. Despite the wealth...... of work on modeling the AGN FeII emission and the need to account for it in observed AGN spectra, there is no UV template electronically available to aid this process. The iron template we present is based on HST spectra of the Narrow Line Seyfert 1, IZw1. Its intrinsic narrow lines (~900 km/s) and rich...... iron spectrum make the template particularly suitable for use with most AGN spectra. The iron emission spectrum and the line identifications and measurements are presented and compared with the work of Laor et al. We illustrate the application of the derived FeII and FeIII templates by fitting...

  16. X-ray Fluorescent Fe Kalpha Lines from Stellar Photospheres

    CERN Document Server

    Drake, Jeremy J; Swartz, Douglas A

    2007-01-01

    X-ray spectra from stellar coronae are reprocessed by the underlying photosphere through scattering and photoionization events. While reprocessed X-ray spectra reaching a distant observer are at a flux level of only a few percent of that of the corona itself, characteristic lines formed by inner shell photoionization of some abundant elements can be significantly stronger. The emergent photospheric spectra are sensitive to the distance and location of the fluorescing radiation and can provide diagnostics of coronal geometry and abundance. Here we present Monte Carlo simulations of the photospheric Kalpha doublet arising from quasi-neutral Fe irradiated by a coronal X-ray source. Fluorescent line strengths have been computed as a function of the height of the radiation source, the temperature of the ionising X-ray spectrum, and the viewing angle. We also illustrate how the fluorescence efficiencies scale with the photospheric metallicity and the Fe abundance. Based on the results we make three comments: (1) fl...

  17. Types of greenhouse gas emissions in the production of cast iron and steel

    Science.gov (United States)

    Lisienko, V. G.; Chesnokov, Yu N.; Lapteva, A. V.; Noskov, V. Yu

    2016-09-01

    Types of carbon dioxide emissions in iron and steel production are indicated. Production processes have been classified according to mechanisms of carbon dioxide formation. Mathematical models for calculation of carbon dioxide emissions for each type of process are found. Calculations results of carbon dioxide emissions of coke (BF + EAF) and cokeless processes (Corex, Midrex, HyL-3, Romelt) in combination with EAF are provided.

  18. Wavelengths, oscillator strengths and radiative transition rates for K{alpha} lines in titanium x-ray spectra

    Energy Technology Data Exchange (ETDEWEB)

    Hu Feng; Wang Chuangke; Zhao Xuefeng [Research Center of Laser Fusion, China Academy of Engineering Physics, Mianyang 621900 (China); Yang Jiamin; Jiang Gang, E-mail: yjm70018@my-public.sc.cninfo.net [Institute of Atomic and Molecular Physics, Sichuan University, Chengdu 610064 (China)

    2011-06-15

    The oscillator strengths, line strengths and wavelengths are presented for all 1s-2p transitions in titanium ions. X-ray emission from titanium is extensively used, for example for diagnosis, in fusion experiments. The K{alpha} 1s-2p transitions are limited to transitions from helium-like to fluorine-like ion as the 2p subshell is filled beyond fluorine. While there are two 1s-2p transitions (1s{sup 2}S{sub 1/2}-2p{sup 2}P{sub 1/2} and 1s{sup 2}S{sub 1/2}-2p{sup 2}P{sub 3/2}) for hydrogen-like titanium, Ti{sup 20+}, the number varies depending on the number of electrons in the 2p subshell before and after the transition. For example, there are 35 1s-2p transitions giving the same number of K{alpha} lines for carbon-like titanium, Ti{sup 16+}. The present results are obtained from configuration interaction atomic structure calculations using the code GRASPVU, which includes relativistic effects in the Dirac-Fock approximation. The results have been benchmarked for a few ionic states. A comparison of our results with the very few transitions in the literature as well as those from other codes shows reasonable accuracy of the present results.

  19. L- and K-shell emission from X-FEL heated iron

    Science.gov (United States)

    Heimann, Philip; Hansen, Stephanie; Loisel, Guillaume; Bailey, James; Gamboa, Eliseo; Glenzer, Siegfried; Mancini, Roberto; Saunders, Alison; Falcone, Roger; Galtier, Eric

    2016-10-01

    At the LCLS MEC instrument, a tightly focused X-ray FEL beam is used to isochorically heat thin iron samples. Two compound refractive lenses produce a focus estimated to be 0.5 microns (FWHM). The L-emission from the hot, solid-density samples is measured by RAP(001) crystal and grating spectrometers. In addition, the K-emission is observed by a Ge(111) crystal spectrometer. The L-shell emission from iron, which is initially photoionized by the X-ray FEL, tests recent measurements indicating higher-than-predicted broadening of the L-shell emission lines. Heating at 7 and 9.2 keV photon energies compares different heating mechanisms.

  20. An intense and broad FeKalpha line observed in the X-ray luminous quasar Q0056-363 with XMM-Newton

    CERN Document Server

    Porquet, D; Porquet, Delphine

    2003-01-01

    We present an XMM-Newton observation of the radio-quiet quasar Q0056-363 (z=0.162). This is the first time that this quasar is observed in the hard X-ray range (above 2 keV). We find that Q0056-363 is a powerful X-ray quasar, with a 0.3-12 keV unabsorbed luminosity of about 1.2 x 10^45 erg s-1 with the largest part (~67%) emitted below 2 keV. The spectrum reveals a large featureless soft X-ray excess below 2 keV and a strong broad FeKalpha line at 6.4 keV (in the quasar frame). The FeK alpha line is due to low to moderate ionization states of iron (i.e., < Fe XVII), with an equivalent width of about 250 eV and a velocity width of about 25,000 km s-1. Q0056-363 is presently the most luminous AGN known to exhibit such a broad and intense FeKalpha line profile from near neutral iron. The line can be fitted with a relativistic profile from an accretion disc around either a Schwarzschild (non-rotating) or a Kerr (rotating) black hole. A combination of two thermal Comptonization components and a disc reflection ...

  1. Method for characterization of a spherically bent crystal for K.alpha. X-ray imaging of laser plasmas using a focusing monochromator geometry

    Science.gov (United States)

    Kugland, Nathan; Doeppner, Tilo; Glenzer, Siegfried; Constantin, Carmen; Niemann, Chris; Neumayer, Paul

    2015-04-07

    A method is provided for characterizing spectrometric properties (e.g., peak reflectivity, reflection curve width, and Bragg angle offset) of the K.alpha. emission line reflected narrowly off angle of the direct reflection of a bent crystal and in particular of a spherically bent quartz 200 crystal by analyzing the off-angle x-ray emission from a stronger emission line reflected at angles far from normal incidence. The bent quartz crystal can therefore accurately image argon K.alpha. x-rays at near-normal incidence (Bragg angle of approximately 81 degrees). The method is useful for in-situ calibration of instruments employing the crystal as a grating by first operating the crystal as a high throughput focusing monochromator on the Rowland circle at angles far from normal incidence (Bragg angle approximately 68 degrees) to make a reflection curve with the He-like x-rays such as the He-.alpha. emission line observed from a laser-excited plasma.

  2. Effect of Tourmaline-Doped on the Far Infrared Emission of Iron Ore Tailings Ceramics.

    Science.gov (United States)

    Liu, Jie; Meng, Junping; Liang, Jinsheng; Zhang, Hongchen; Gu, Xiaoyang

    2016-04-01

    Iron ore tailings as secondary resources have been of great importance to many countries in the world. Their compositions are similar to that of infrared emission ceramics, but there are few reports about it. In addition, tourmaline has high infrared emission properties due to its unique structure. With the purpose of expanding functional utilization of iron ore tailings, as well as reducing the production cost of far infrared ceramics, a new kind of far infrared emission ceramics was prepared by using iron ore tailings, calcium carbonate, silica, and natural tourmaline. The ceramics powders were characterized by Fourier transform infrared spectroscope, X-ray diffraction and scanning electron microscopy, respectively. The results show that after being sintered at 1065 °C, the percentage of pseudobrookite and lattice strain of samples increased with increasing the elbaite content. Furthermore, the added tourmaline was conducive to the densification sintering of ceramics. The appearance of Li-O vibration at 734.73 cm-1, as well as the strengthened Fe-O vibration at 987.68 cm-1 were attributed to the formation of Li0.375Fe1.23Ti1.4O5 solid solution, which led the average far infrared emissivity of ceramics increase from 0.861 to 0.906 within 8-14 µm.

  3. Iron

    Science.gov (United States)

    Iron is a mineral that our bodies need for many functions. For example, iron is part of hemoglobin, a protein which carries ... It helps our muscles store and use oxygen. Iron is also part of many other proteins and ...

  4. Iron

    Science.gov (United States)

    ... of iron stored in the body become low, iron deficiency anemia sets in. Red blood cells become smaller and ... from the lungs throughout the body. Symptoms of iron deficiency anemia include tiredness and lack of energy, GI upset, ...

  5. Updated atmospheric speciated mercury emissions from iron and steel production in China during 2000–2015

    Directory of Open Access Journals (Sweden)

    Q. Wu

    2017-09-01

    Full Text Available Iron and steel production (ISP is one of the significant atmospheric Hg emission sources in China. Atmospheric mercury (Hg emissions from ISP during 2000–2015 were estimated by using a technology-based emission factor method. To support the application of this method, databases of Hg concentrations in raw materials, technology development trends, and Hg removal efficiencies of air pollution control devices (APCDs were constructed through national sampling and literature review. Hg input to ISP increased from 21.6 t in 2000 to 94.5 t in 2015. In the various types of raw materials, coking coal and iron concentrates contributed 35–46 and 25–32 % of the total Hg input. Atmospheric Hg emissions from ISP increased from 11.5 t in 2000 to 32.7 t in 2015 with a peak of 35.6 t in 2013. Pollution control promoted the increase in average Hg removal efficiency, from 47 % in 2000 to 65 % in 2015. During the study period, sinter/pellet plants and blast furnaces were the largest two emission processes. However, emissions from roasting plants and coke ovens cannot be ignored, which accounted for 22–34 % of ISP's emissions. Overall, Hg speciation shifted from 50/44/6 (gaseous elemental Hg (Hg0/gaseous oxidized Hg (HgII/particulate-bound Hg (Hgp in 2000 to 40/59/1 in 2015, which indicated a higher proportion of Hg deposition around the emission points. Future emissions of ISP were expected to decrease based on the comprehensive consideration crude-steel production, steel scrap utilization, energy saving, and pollution control measures.

  6. X-ray spectra of Hercules X-1. I - Iron line fluorescence from a subrelativistic shell

    Science.gov (United States)

    Pravdo, S. H.; Becker, R. H.; Boldt, E. A.; Holt, S. S.; Serlemitsos, P. J.; Swank, J. H.

    1977-01-01

    The X-ray spectrum of Her X-1 was observed in the energy range from 2 to 24 keV from August 29 to September 3, 1975. Emission features are observed near the K-alpha iron-line energy which exhibit both broadening and a double line structure. The total luminosity in these features is about 4 by 10 to the 35th power ergs/s. Iron line fluorescence from an opaque cool (not exceeding 1 million K) shell of material at the Alfven surface provides the necessary luminosity in this feature. The double line structure and the line energy width can be due to Doppler shifts if the shell is forced to corotate with the pulsar at a radius of at least 800 million cm. Implications of this model regarding physical conditions near Her X-1 are discussed.

  7. System and method for making metallic iron with reduced CO.sub.2 emissions

    Science.gov (United States)

    Kiesel, Richard F; Englund, David J; Schlichting, Mark; Meehan, John; Crouch, Jeremiah; Wilson, Logan

    2014-10-14

    A method and system for making metallic iron nodules with reduced CO.sub.2 emissions is disclosed. The method includes: assembling a linear hearth furnace having entry and exit portions, at least a conversion zone and a fusion zone, and a moving hearth adapted to move reducible iron bearing material through the furnace on contiguous hearth sections; assembling a shrouded return substantially free of air ingress extending adjacent at least the conversion and fusion zones of the furnace through which hearth sections can move from adjacent the exit portion to adjacent the entry portion of the furnace; transferring the hearth sections from the furnace to the shrouded return adjacent the exit portion; reducing reducible material in the linear hearth furnace to metallic iron nodules; and transporting gases from at least the fusion zone to the shrouded return to heat the hearth sections while in the shrouded return.

  8. Mega fire emissions in Siberia: potential supply of bioavailable iron from forests to the ocean

    Directory of Open Access Journals (Sweden)

    A. Ito

    2011-06-01

    Full Text Available Significant amounts of carbon and nutrients are released to the atmosphere due to large fires in forests. Characterization of the spatial distribution and temporal variation of the intense fire emissions is crucial for assessing the atmospheric loadings of trace gases and aerosols. This paper discusses issues of the representation of forest fires in the estimation of emissions and the application to an atmospheric chemistry transport model (CTM. The potential contribution of forest fires to the deposition of bioavailable iron (Fe into the ocean is highlighted, with a focus on mega fires in eastern Siberia.

    Satellite products of burned area, active fire, and land cover are used to estimate biomass burning emissions in conjunction with a biogeochemical model. Satellite-derived plume height from MISR is used for the injection height of boreal forest fire emissions. This methodology is applied to quantify fire emission rates in each three-dimensional grid location in the high latitude Northern Hemisphere (>30° N latitude over a 5-yr period from 2001 to 2005. There is large interannual variation in forest burned area during 2001–2005 (13–49 × 103 km2 yr−1 which results in a corresponding variation in the annual emissions of carbon monoxide (CO (14–81 Tg CO y−1. Satellite observations of CO column from MOPITT are used to evaluate the model performance in simulating the spatial distribution and temporal variation of the fire emissions. The model results for CO enhancements due to eastern Siberian fires are in good agreement with MOPITT observations. These validation results suggest that the model using emission rates estimated in this work is able to describe the interannual changes in CO due to intense forest fires.

    Bioavailable iron is derived from atmospheric processing of relatively insoluble iron from desert sources by anthropogenic pollutants (mainly sulfuric acid formed

  9. Iron oxidation kinetics study by using infrared spectral emissivity measurements below 570deg. C

    Energy Technology Data Exchange (ETDEWEB)

    Campo, Leire del [Departamento de Fisica de la Materia Condensada, Facultad de Ciencia y Tecnologi' a, Universidad del Pai' s Vasco, Barrio Sarriena s/n, 48940 Leioa, Bizkaia (Spain); Perez-Saez, Raul B. [Departamento de Fisica de la Materia Condensada, Facultad de Ciencia y Tecnologi' a, Universidad del Pai' s Vasco, Barrio Sarriena s/n, 48940 Leioa, Bizkaia (Spain); Instituto de Sintesis y Estudio de Materiales, Universidad del Pais Vasco, Apdo. 644, 48080 Bilbao (Spain)], E-mail: raul.perez@ehu.es; Tello, Manuel J. [Departamento de Fisica de la Materia Condensada, Facultad de Ciencia y Tecnologi' a, Universidad del Pai' s Vasco, Barrio Sarriena s/n, 48940 Leioa, Bizkaia (Spain); Instituto de Sintesis y Estudio de Materiales, Universidad del Pais Vasco, Apdo. 644, 48080 Bilbao (Spain)

    2008-01-15

    The oxidation kinetics of iron below 570deg. C is investigated through the dependence of the spectral emissivity on the surface oxidation state. Using the theory of radiative effects of thin films, the oxide scale thickness is obtained as a function of time. A parabolic growth has been observed in all the cases, and applying Wagner's theory, the oxidation parabolic rate constants have been calculated at four temperatures. The temperature dependence of these results has additionally been used to obtain the activation energy of the oxidation process in iron. The parabolic rate constants and activation energy values are in good agreement with the theoretical predictions, and this suggests that the lattice diffusion mechanisms for the high temperature magnetite growth also occur until 400deg. C. The experimental results are also useful to test the applicability of emissivity measurements for in situ oxidation kinetics studies in the spectral range where the scales are optically thin.

  10. Analysis of emissions collected from four types of iron casting molds.

    Science.gov (United States)

    Palmer, W G; James, R H; Moorman, W J

    1985-12-01

    The levels of polycyclic aromatic hydrocarbons (PAH) and related compounds, phenols and particulates were determined in emissions collected from iron casting molds composed of four different types of chemical binders: furan, urethane, green sand with sea coal and phenol-formaldehyde resins in shell molds. The shell sample, with 50% particulates, contained the most water-soluble material; green sand, 25% particulates; furan, 10% particulates; and urethane, less than 2% particulate material. The portion of the particulate fraction soluble in cyclohexane varies from 16 to 36% between mold types; emissions from urethane and furan molds contained the lowest quantities of cyclohexane-soluble components and of PAH and related compounds. Phenol, which was found in all four foundry samples, was present in the highest concentration in emissions from urethane molds. Shell mold emissions contained the highest levels of 2- and 4-nitrophenol.

  11. Emission mechanisms in stabilized iron-passivated porous silicon: Temperature and laser power dependences

    Energy Technology Data Exchange (ETDEWEB)

    Rahmani, M. [Unite de Spectroscopie Raman, Faculte des Sciences de Tunis, Universite de Tunis El Manar, 2092 El Manar, Tunis (Tunisia); Moadhen, A., E-mail: adel.moadhen@fst.rnu.tn [Unite de Spectroscopie Raman, Faculte des Sciences de Tunis, Universite de Tunis El Manar, 2092 El Manar, Tunis (Tunisia); Mabrouk Kamkoum, A. [Unite de Spectroscopie Raman, Faculte des Sciences de Tunis, Universite de Tunis El Manar, 2092 El Manar, Tunis (Tunisia); Zaiebi, M.-A. [Unite de Spectroscopie Raman, Faculte des Sciences de Tunis, Universite de Tunis El Manar, 2092 El Manar, Tunis (Tunisia); Ecole Superieure des Sciences et Techniques de Tunis, Universite de Tunis, 5 Av. Taha Hussein, 1008 Montfleury, Tunis (Tunisia); Chtourou, R. [Laboratoire de Photovoltaieque et de Semiconducteurs, Centre de Recherche et de Technologie de l' Energie, BP 95, Hammam-Lif 2050 (Tunisia); Haji, L. [Universite Europeenne de Bretagne, CNRS FOTON-UMR 6082, 6 rue de Kerampont, BP 80518, 22305 Lannion Cedex (France); Oueslati, M. [Unite de Spectroscopie Raman, Faculte des Sciences de Tunis, Universite de Tunis El Manar, 2092 El Manar, Tunis (Tunisia)

    2012-02-01

    Photoluminescence (PL) measurements of porous silicon (PS) and iron-porous silicon nanocomposites (PS/Fe) with stable optical properties versus temperature and laser power density have been investigated. The presence of iron in PS matrix is confirmed by Raman spectroscopy. The PL intensity of PS and PS/Fe increases at low temperature, the evolution of integrated PL intensity follows the modified Arrhenius model. The incorporation of iron in PS matrix reduces the activation energy traducing the existence of shallow levels related to iron atoms. Also, the temperature dependence of the porous silicon PL peak position follows a linear evolution at high temperature and a quadratic one at low temperature. Such evolution is due to the thermal carriers' redistribution and an energy transfer. Similarly, we have compared the laser power dependence of the PL in PS and PS/Fe layers. The results prove that the recombination process in PS is realised through the lower energy traps localised in the electronic gap. However, the observed emission in PS/Fe is essentially due to direct transitions. So, we can conclude that the presence of iron in PS matrix induces a strong modification of the PL mechanisms.

  12. Iron ore industry emissions as a potential ecological risk factor for tropical coastal vegetation.

    Science.gov (United States)

    Kuki, Kacilda N; Oliva, Marco A; Pereira, Eduardo G

    2008-07-01

    In the coastal zone of the Espírito Santo state, Brazil, fragments of restinga, which form a natural ecosystem, share their space with an increasing number of iron ore industries. The iron ore dust and SO(2) originating from the industry processing activities can interfere with the vegetation of the adjacent ecosystems at various levels. This study was undertaken in order to evaluate the effects of industry emissions on representative members of the restinga flora, by measuring physiological and phenological parameters. Foliar samples of Ipomoea pes caprae, Canavalia rosea, Sophora tomentosa, and Schinus terebinthifolius were collected at three increasing distances from an ore industry (1.0, 5.0, and 15.0 km), and were assessed for their dust deposition, chlorophyll, and Fe content. Phenological monitoring was focused on the formation of shoots, flowers, and fruits and was also performed throughout the course of a year. The results showed that the edaphic characteristics and the mineral constitutions of the plants were affected by industry emissions. In addition, the chlorophyll content of the four species increased with proximity to the industry. Phenological data revealed that the reproductive effort, as measured by fruit production, was affected by emissions and S. tomentosa was the most affected species. The use of an integrative approach that combines biochemical and ecological data indicates that the restinga flora is under stress due to industry emissions, which on a long-term basis may put the ecosystem at risk.

  13. Iron Ore Industry Emissions as a Potential Ecological Risk Factor for Tropical Coastal Vegetation

    Science.gov (United States)

    Kuki, Kacilda N.; Oliva, Marco A.; Pereira, Eduardo G.

    2008-07-01

    In the coastal zone of the Espírito Santo state, Brazil, fragments of restinga, which form a natural ecosystem, share their space with an increasing number of iron ore industries. The iron ore dust and SO2 originating from the industry processing activities can interfere with the vegetation of the adjacent ecosystems at various levels. This study was undertaken in order to evaluate the effects of industry emissions on representative members of the restinga flora, by measuring physiological and phenological parameters. Foliar samples of Ipomoea pes caprae, Canavalia rosea, Sophora tomentosa, and Schinus terebinthifolius were collected at three increasing distances from an ore industry (1.0, 5.0, and 15.0 km), and were assessed for their dust deposition, chlorophyll, and Fe content. Phenological monitoring was focused on the formation of shoots, flowers, and fruits and was also performed throughout the course of a year. The results showed that the edaphic characteristics and the mineral constitutions of the plants were affected by industry emissions. In addition, the chlorophyll content of the four species increased with proximity to the industry. Phenological data revealed that the reproductive effort, as measured by fruit production, was affected by emissions and S. tomentosa was the most affected species. The use of an integrative approach that combines biochemical and ecological data indicates that the restinga flora is under stress due to industry emissions, which on a long-term basis may put the ecosystem at risk.

  14. Mega fire emissions in Siberia: potential supply of soluble iron from forests to the ocean

    Directory of Open Access Journals (Sweden)

    A. Ito

    2011-02-01

    Full Text Available Significant amounts of carbon and nutrients are released to the atmosphere due to large fires in forests. Characterization of the spatial distribution and temporal variation of the intense fire emissions is crucial for assessing the atmospheric loadings of aerosols and trace gases. This paper discusses issues of the representation of forest fires in the estimation of emissions and the application to an atmospheric chemistry transport model (CTM. The potential contribution of forest fires to the deposition of soluble iron (Fe into the ocean is highlighted, with a focus on mega fires in eastern Siberia. Satellite products of burned area, active fire, and land cover are used to estimate biomass burning emissions in conjunction with a biogeochemical model. Satellite-derived plume height from MISR is used for the injection height of boreal forest fire emissions. This methodology is applied to quantify fire emission rates in each three-dimensional grid location in the high latitude Northern Hemisphere (> 30° N latitude over a 5-year period from 2001 to 2005. There is large interannual variation in forest burned area during 2001–2005 (13–51 × 103 km2 yr−1 which results in a corresponding variation in the annual emissions of carbon monoxide (CO (12–78 Tg CO yr−1. Satellite observations of CO from MOPITT are used to evaluate the model performance in simulating the spatial distribution and temporal variation of the fire emissions. During the major Siberian fire seasons in the summer of 2002 and in the spring of 2003, the model results for CO enhancements due to intense fires are in good agreement with MOPITT observations. These fire emission rates are applied to the aerosol chemistry transport model to examine the relative importance of biomass burning sources of soluble iron compared to those from dust sources. Compared to the dust sources without the atmospheric processing by acidic species

  15. Role of emission angular directionality in spin determination of accreting black holes with broad iron line

    CERN Document Server

    Svoboda, J; Goosmann, R W; Karas, V

    2009-01-01

    Spin of an accreting black hole can be determined by spectroscopy of the emission and absorption features produced in the inner regions of an accretion disc. We discuss the method employing the relativistic line profiles of iron in the X-ray domain, where the emergent spectrum is blurred by general relativistic effects. Precision of spectra fitting procedure could be compromised by inappropriate account of the angular distribution of the disc emission. Often a unique profile is assumed, invariable over the entire range of radii in the disc and energy in the spectral band. We study how sensitive the spin determination is to the assumptions about the intrinsic angular distribution of the emitted photons. We find that the uncertainty of the directional emission distribution translates to 20% uncertainty in determination of the marginally stable orbit. By assuming a rotating black hole in the centre of an accretion disc, we perform radiation transfer computations of an X-ray irradiated disc atmosphere to determin...

  16. [Characteristic of Mercury Emissions and Mass Balance of the Typical Iron and Steel Industry].

    Science.gov (United States)

    Zhang, Ya-hui; Zhang, Cheng; Wang, Ding-yong; Luo, Cheng-zhong; Yang, Xi; Xu, Feng

    2015-12-01

    To preliminarily discuss the mercury emission characteristics and its mass balance in each process of the iron and steel production, a typical iron and steel enterprise was chosen to study the total mercury in all employed materials and estimate the input and output of mercury during the steel production process. The results showed that the mercury concentrations of input materials in each technology ranged 2.93-159.11 µg · kg⁻¹ with the highest level observed in ore used in blast furnace, followed by coal of sintering and blast furnace. The mercury concentrations of output materials ranged 3.09-18.13 µg · kg⁻¹ and the mercury concentration of dust was the highest, followed by converter slag. The mercury input and the output in the coking plant were 1346.74 g · d⁻¹ ± 36.95 g · d⁻¹ and 177.42 g · d⁻¹ ± 13.73 g · d⁻¹, respectively. In coking process, mercury mainly came from the burning of coking coal. The sintering process was the biggest contributor for mercury input during the iron and steel production with the mercury input of 1075. 27 g · d⁻¹ ± 60.89 g · d⁻¹ accounting for 68.06% of the total mercury input during this production process, and the ore powder was considered as the main mercury source. For the solid output material, the output in the sintering process was 14.15 g · d⁻¹ ± 0.38 g · d⁻¹, accounting for 22.61% of the total solid output. The mercury emission amount from this studied iron and steel enterprise was estimated to be 553.83 kg in 2013 with the emission factor of 0.092 g · t⁻¹ steel production. Thus, to control the mercury emissions, iron and steel enterprises should combine with production practice, further reduce energy consumption of coking and sintering, or improve the quality of raw materials and reduce the input of mercury.

  17. Iron and Nickel Line Diagnostics for the Galactic Center Diffuse Emission

    CERN Document Server

    Koyama, K; Inui, T; Nakajima, H; Matsumoto, H; Tsuru, T G; Takahashi, T; Maeda, Y; Yamazaki, N; Murakami, H; Yamauchi, S; Tsuboi, Y; Senda, A; Kataoka, J; Takahashi, H; Holt, S S; Brown, G V; Koyama, Katsuji; Hyodo, Yoshiaki; Inui, Tatsuya; Nakajima, Hiroshi; Matsumoto, Hironori; Tsuru, Takeshi Go; Takahashi, Tadayuki; Maeda, Yoshitomo; Yamazaki, Noriko; Murakami, Hiroshi; Yamauchi, Shigeo; Tsuboi, Yohko; Senda, Atsushi; Kataoka, Jun; Takahashi, Hiromitsu; Holt, Stephen S; Brown, Gregory V

    2006-01-01

    We have observed the diffuse X-ray emission from the Galactic center (GC) using the X-ray Imaging Spectrometer (XIS) on Suzaku. The high-energy resolution and the low-background orbit provide excellent spectra of the GC diffuse X-rays (GCDX). The XIS found many emission lines in the GCDX near the energy of K-shell transitions of iron and nickel. The most pronounced features are FeI K alpha at 6.4 keV and K-shell absorption edge at 7.1 keV, which are from neutral and/or low ionization states of iron, and the K-shell lines at 6.7 keV and 6.9 keV from He-like (FeXXV K alpha) and hydrogenic (FeXXVI Ly alpha) ions of iron. In addition, K alpha lines from neutral or low ionization nickel (NiI K alpha) and He-like nickel (NiXXVII K alpha), and FeI K beta, FeXXV K beta, FeXXVI Ly beta, FeXXV K gamma and FeXXVI Ly gamma are detected for the first time. The line center energies and widths of FeXXV K alpha and FeXXVI Ly alpha favor a collisional excitation (CE) plasma for the origin of the GCDX. The electron temperature...

  18. India's iron and steel industry: Productivity, energy efficiency and carbon emissions

    Energy Technology Data Exchange (ETDEWEB)

    Schumacher, Katja; Sathaye, Jayant

    1998-10-01

    Historical estimates of productivity growth in India's iron and steel sector vary from indicating an improvement to a decline in the sector's productivity. The variance may be traced to the time period of study, source of data for analysis, and type of indices and econometric specifications used for reporting productivity growth. The authors derive both growth accounting and econometric estimates of productivity growth for this sector. Their results show that over the observed period from 1973--74 to 1993--94 productivity declined by 1.71{percent} as indicated by the Translog index. Calculations of the Kendrick and Solow indices support this finding. Using a translog specification the econometric analysis reveals that technical progress in India's iron and steel sector has been biased towards the use of energy and material, while it has been capital and labor saving. The decline in productivity was caused largely by the protective policy regarding price and distribution of iron and steel as well as by large inefficiencies in public sector integrated steel plants. Will these trends continue into the future, particularly where energy use is concerned? Most likely they will not. The authors examine the current changes in structure and energy efficiency undergoing in the sector. Their analysis shows that with the liberalization of the iron and steel sector, the industry is rapidly moving towards world-best technology, which will result in fewer carbon emissions and more efficient energy use in existing and future plants.

  19. Iron

    DEFF Research Database (Denmark)

    Hansen, Jakob Bondo; Moen, I W; Mandrup-Poulsen, T

    2014-01-01

    The interest in the role of ferrous iron in diabetes pathophysiology has been revived by recent evidence of iron as an important determinant of pancreatic islet inflammation and as a biomarker of diabetes risk and mortality. The iron metabolism in the β-cell is complex. Excess free iron is toxic......, but at the same time, iron is required for normal β-cell function and thereby glucose homeostasis. In the pathogenesis of diabetes, iron generates reactive oxygen species (ROS) by participating in the Fenton chemistry, which can induce oxidative damage and apoptosis. The aim of this review is to present...... and discuss recent evidence, suggesting that iron is a key pathogenic factor in both type 1 and type 2 diabetes with a focus on inflammatory pathways. Pro-inflammatory cytokine-induced β-cell death is not fully understood, but may include iron-induced ROS formation resulting in dedifferentiation by activation...

  20. Resonant K-alpha spectroscopy of a hot dense plasma created by the LCLS x-ray free electron laser

    Science.gov (United States)

    Cho, Byoung-Ick; Engelhorn, K.; Falcone, R. W.; Heimann, P. A.; Vinko, S. M.; Ciricosta, O.; Higginbotham, A.; Murphy, C.; Wark, J. S.; Chung, H.-K.; Brown, C. R. D.; Burian, T.; Vysin, L.; Juha, L.; Lee, H. J.; Messersmidt, M.; Schlotter, W.; Turner, J.; Nagler, B.; Ping, Y.; Lee, R. W.; Toleikis, S.; Zastrau, U.

    2011-10-01

    We present one of the first experimental studies of the interaction of high intensity x-ray free electron laser radiation with solid density matter. In the experiment performed at the LCLS, an intense 80 fs x-ray pulse at 1017 Wcm-2 with photon energies of 1480 ~ 1560 eV is focused on a thin Al foil and K-alpha emission spectra are observed. Although x-ray photon energy is lower than the absorption edge, because of its high intensity the sample is surprisingly heated up to 100 ~200 eV in the pulse duration and a hot dense plasma is created. Observed x-ray spectra indicate this dense plasma resonantly interacts with the x-ray photons. The emission spectra are also simulated using the collisional-radiative code, SCFLY which provides information about the electron temperature and density, the charge state distribution and opacity. The comparison of experiment and simulation provides a detailed description of a dense plasma resonantly interacting with an intense x-ray pulse.

  1. Chemical constituents in particulate emissions from an integrated iron and steel facility.

    Science.gov (United States)

    Tsai, Jiun-Horng; Lin, Kuo-Hsiung; Chen, Chih-Yu; Ding, Jian-Yuan; Choa, Ching-Guan; Chiang, Hung-Lung

    2007-08-17

    Particle emissions from four integrated iron and steel plant processes, i.e., coke making, sintering, cold forming, and hot forming, were investigated in this study. Particle compositions of 21 element species, 11 ionic species, elemental carbon (EC), organic carbon (OC) and 16 polyaromatic hydrocarbons (PAHs) were analyzed to create "fingerprints" of the particles emitted from various processes in an integrated iron and steel plant. Results indicated that element compositions (0.11-0.42 g/g), water-soluble ions (0.34-0.52 g/g), elemental carbon (0.008-0.14 g/g), organic carbon (0.02-0.06 g/g) and PAHs (0.52-6.2 mg/g) contributed to the particle mass. In general, sulfur had a higher mass contribution than the other elements, which resulted from the use of coal, flux, heavy oil, and many recycled materials in the iron and steel plant. The particle mass contribution of potassium and chlorine in the sinter plant was higher than in other processes; this may be attributed to the lower boiling point and volatility of potassium. In addition, many recycled materials were fed into the sinter plant, causing a high concentration of potassium and chlorine in the particle phase. Eight PAH compounds were analyzed in the four processes. The carcinogenic compound Benzo(a)pyrene (BaP) was detectable only in the sintering process.

  2. Decomposition analysis of energy-related carbon dioxide emissions in the iron and steel industry in China

    Institute of Scientific and Technical Information of China (English)

    Wenqiang SUN; Jiuju CAI, Hai YU, Lei DAI

    2012-01-01

    This work aims to identify the main factors influencing the energy-related carbon dioxide (CO2) emissions from the iron and steel industry in China during the period of 1995-2007. The logarithmic mean divisia index (LMDI) technique was applied with period-wise analysis and time-series analysis. Changes in energy- related CO2 emissions were decomposed into four factors: emission factor effect, energy structure effect, energy consumption effect, and the steel production effect. The results show that steel production is the major factor responsible for the rise in CO2 emissions during the sampling period; on the other hand the energy consump- tion is the largest contributor to the decrease in C02 emissions. To a lesser extent, the emission factor and energy structure effects have both negative and positive contributions to C02 emissions, respectively. Policy implications are provided regarding the reduction of C02 emissions from the iron and steel industry in China, such as controlling the overgrowth of steel production, improving energy-saving technologies, and introducing low-carbon energy sources into the iron and steel industry.

  3. A deep X-ray view of the bare AGN Ark 120. II. Evidence for Fe K emission transients

    CERN Document Server

    Nardini, E; Reeves, J N; Braito, V; Lobban, A; Matt, G

    2016-01-01

    We report on the results from a large observational campaign on the bare Seyfert galaxy Ark 120, jointly carried out in 2014 with XMM-Newton, Chandra, and NuSTAR. The fortunate line of sight to this source, devoid of any significant absorbing material, provides an incomparably clean view to the nuclear regions of an active galaxy. Here we focus on the analysis of the iron fluorescence features, which form a composite emission pattern in the 6$-$7 keV band. The prominent K$\\alpha$ line from neutral iron at 6.4 keV is resolved in the Chandra High-Energy Transmission Grating spectrum to a full-width at half maximum of 4700$^{+2700}_{-1500}$ km s$^{-1}$, consistent with an origin from the optical broad-line region. Excess components are detected on both sides of the narrow K$\\alpha$ line: the red one (6.0$-$6.3 keV) clearly varies in strength in about one year, and hints at the presence of a broad, mildly asymmetric line from the accretion disk; the blue one (6.5$-$7.0 keV), instead, is likely a blend of differen...

  4. K-alpha X-rays from cosmic-ray oxygen. [subrelativistic interstellar oxygen ions

    Science.gov (United States)

    Pravdo, S. H.; Boldt, E. A.

    1975-01-01

    Equilibrium charge fractions are calculated for subrelativistic cosmic-ray oxygen ions in the interstellar medium. These are used to determine the expected flux of K-alpha rays arising from atomic processes for a number of different postulated interstellar oxygen spectra. Relation of these results to the diffuse X-ray background measured at the appropriate energy (about 0.6 keV) suggests an observable broadened line feature.

  5. An XMM-Newton survey of broad iron lines in AGN

    CERN Document Server

    Nandra, K; George, I M; Reeves, J N; Turner, T J

    2006-01-01

    We report on the iron K-alpha line properties of a sample of Seyfert galaxies observed with the XMM-Newton EPIC pn instrument. Using a systematic and uniform analysis, we find that complexity at iron-K is extremely common in the XMM spectra. Once appropriate soft X-ray absorption, narrow 6.4 keV emission and associated Compton reflection are accounted for, ~75 of the sample show an improvement when a further Gaussian component is introduced. The typical properties of the broad emission are both qualitatively and quantitatively consistent with previous results from ASCA. The complexity is in general very well described by relativistic accretion disk models. In most cases the characteristic emission radius is constrained to be within ~50 R_g, where strong gravitational effects become important. We find in about 1/3 of the sample the accretion disk interpretation is strongly favoured over competing models. In a few objects no broad line is apparent. We find evidence for emission within 6 R_g in only two cases, b...

  6. Solid Fuel - Oxygen Fired Combustion for Production of Nodular Reduced Iron to Reduce CO2 Emissions and Improve Energy Efficiencies

    Energy Technology Data Exchange (ETDEWEB)

    Donald R. Fosnacht; Richard F. Kiesel; David W. Hendrickson; David J. Englund; Iwao Iwasaki; Rodney L. Bleifuss; Mathew A. Mlinar

    2011-12-22

    The current trend in the steel industry is an increase in iron and steel produced in electric arc furnaces (EAF) and a gradual decline in conventional steelmaking from taconite pellets in blast furnaces. In order to expand the opportunities for the existing iron ore mines beyond their blast furnace customer base, a new material is needed to satisfy the market demands of the emerging steel industry while utilizing the existing infrastructure and materials handling capabilities. This demand creates opportunity to convert iron ore or other iron bearing materials to Nodular Reduced Iron (NRI) in a recently designed Linear Hearth Furnace (LHF). NRI is a metallized iron product containing 98.5 to 96.0% iron and 2.5 to 4% C. It is essentially a scrap substitute with little impurity that can be utilized in a variety of steelmaking processes, especially the electric arc furnace. The objective of this project was to focus on reducing the greenhouse gas emissions (GHG) through reducing the energy intensity using specialized combustion systems, increasing production and the use of biomass derived carbon sources in this process. This research examined the use of a solid fuel-oxygen fired combustion system and compared the results from this system with both oxygen-fuel and air-fuel combustion systems. The solid pulverized fuels tested included various coals and a bio-coal produced from woody biomass in a specially constructed pilot scale torrefaction reactor at the Coleraine Minerals Research Laboratory (CMRL). In addition to combustion, the application of bio-coal was also tested as a means to produce a reducing atmosphere during key points in the fusion process, and as a reducing agent for ore conversion to metallic iron to capture the advantage of its inherent reduced carbon footprint. The results from this study indicate that the approaches taken can reduce both greenhouse gas emissions and the associated energy intensity with the Linear Hearth Furnace process for converting

  7. Emission characterization of unintentionally produced persistent organic pollutants from iron ore sintering process in China.

    Science.gov (United States)

    Tian, Bo; Huang, Jun; Wang, Bin; Deng, Shubo; Yu, Gang

    2012-10-01

    Emission of unintentionally produced persistent organic pollutants (Unintentional POPs), including polychlorinated dibenzo-p-dioxins (PCDDs), polychlorinated dibenzofurans (PCDFs), polychorinated biphenyls (PCBs), hexachlorobenzene (HxCBz) and pentachlorobenzene (PeCBz), were investigated in four typical iron ore sintering plants in China. The emission factors and annual mass releases of the Unintentional POPs were calculated. The results indicated that PCDFs contributed more than 60% to the overall toxic equivalent quantity (TEQ) values, while the contribution of the dl-PCBs is relatively low, and only in the range of 8-9%. The dominant congeners of PCDD/Fs and dl-PCBs contributing most to the total TEQ were 1,2,3,7,8-PeCDD, 2,3,4,7,8-PeCDF and PCB-126. With regard to the TEQ contributions, the most abundant homologues were PeCDFs and HxCDD/Fs, followed by PeCDDs and non-ortho dl-PCB, whereas HpCDD/Fs, OCDD/Fs and mono-ortho dl-PCBs almost made no contributions. Due to the massive use of recycled waste in the feeding materials, the average emission factor of PCDD/Fs and dl-PCBs of the four plants was 3.95 μg WHO-TEQ ton(-1). Based on the results, the annual release of PCDD/Fs and dl-PCBs in 2007-2009 were estimated to be 2070 g, 2212 g, and 2307 gWHO-TEQ, respectively. Copyright © 2012 Elsevier Ltd. All rights reserved.

  8. Somatic Mutations in PI3Kalpha: Structural Basis for Enzyme Activation and Drug Design

    Energy Technology Data Exchange (ETDEWEB)

    S Gabelli; D Mandelker; O Schmidt-Kittler; B Vogelstein; L Amzel

    2011-12-31

    The PI3K pathway is a communication hub coordinating critical cell functions including cell survival, cell growth, proliferation, motility and metabolism. Because PI3K{alpha} harbors recurrent somatic mutations resulting in gains of function in human cancers, it has emerged as an important drug target for many types of solid tumors. Various PI3K isoforms are also being evaluated as potential therapeutic targets for inflammation, heart disease, and hematological malignancies. Structural biology is providing insights into the flexibility of the PI3Ks, and providing basis for understanding the effects of mutations, drug resistance and specificity.

  9. K-alpha conversion efficiency measurments for x-ray scattering in inertial confinement fusion plasmas

    Energy Technology Data Exchange (ETDEWEB)

    Kritcher, A L; Neumayer, P; Urry, M K; Robey, H; Niemann, C; Landen, O L; Morse, E; Glenzer, S H

    2006-11-21

    The conversion efficiency of ultra short-pulse laser radiation to K-{alpha} x-rays has been measured for various chlorine-containing targets to be used as x-ray scattering probes of dense plasmas. The spectral and temporal properties of these sources will allow spectrally-resolved x-ray scattering probing with picosecond temporal resolution required for measuring the plasma conditions in inertial confinement fusion experiments. Simulations of x-ray scattering spectra from these plasmas show that fuel capsule density, capsule ablator density, and shock timing information may be inferred.

  10. Energy recovery and abatement potential of CO2 emissions for an integrated iron and steel making enterprise

    Institute of Scientific and Technical Information of China (English)

    2010-01-01

    The typical features for an integrated iron & steelmaking industry are high energy consumption and CO2 emission.The traditional BF-BOF process in an integrated Iron and steelmaking enterprise produces a large amount of residual heat and energy,which has great potential for recovery and abatement potential of CO2 emissions.In this paper,for an integrated Iron & steelmaking enterprise of 10 million tons per year in capacity,the residual heat and energy recovery analysis was conducted.It is indicateded that the residual heat and energy can be recovered as electric power by using present advanced process technology.By means of the distributed power generation,the residual heat and energy can be recovered,with a power generation capacity of 419.5 kWh per ton steel product.Accordingly,the abatement potential of CO2 emissions for an integrated iron & steel making enterprise was also evaluated,which indicated that about 398.5 kg CO2 could be reduced per ton steel product.

  11. Gas emissions from mining voids in Lorraine iron-bearing basin; Emissions gazeuses a partir des vides miniers dans le Bassin Ferrifere Lorrain

    Energy Technology Data Exchange (ETDEWEB)

    Grabowski, D.; Pokryszka, Z. [INERIS, Parc Technologique ALATA, 60 - Verneuil-en-Halatte (France)

    2003-07-01

    A study carried out in the iron basin of Lorraine (France) put the spot on the existence of under-oxygenated and noxious gas emissions (carbon dioxide, radon..) in built-up areas related to former mining works. Site investigations showed that the gas flow was mainly due to natural ventilation mechanisms. A further study is in progress in order to better understand the origin of the atmosphere modification within the old mine workings. (authors)

  12. Sensitivity of the Fe K-alpha Compton shoulder to the geometry and variability of the X-ray illumination of cosmic objects

    CERN Document Server

    Odaka, Hirokazu; Takahashi, Tadayuki; Fabian, Andrew

    2016-01-01

    In an X-ray reflection spectrum, a tail-like spectral feature generated via Compton down-scattering, known as a Compton shoulder (CS), appears at the low-energy side of the iron K$\\alpha$ line. Despite its great diagnostic potential, its use as a spectral probe of the reflector has been seriously limited due to observational difficulties and modelling complexities. We revisit the basic nature of the CS by systematic investigation into its dependence on spatial and temporal parameters. The calculations are performed by Monte-Carlo simulations for sphere and slab geometries. The dependence is obtained in a two-dimensional space of column density and metal abundance, demonstrating that the CS solves parameter degeneration between them which was seen in conventional spectral analysis using photoelectric absorption and fluorescence lines. Unlike the iron line, the CS does not suffer from any observational dependence on the spectral hardness. The CS profile is highly dependent on the inclination angle of the slab g...

  13. Dependence of the broad Fe K$\\alpha$ line on the physical parameters of AGN

    CERN Document Server

    Liu, Zhu; Lu, Youjun; Carrera, Francisco J; Falocco, Serena; Dong, Xiao-Bo

    2016-01-01

    In this paper, the dependence of the broad Fe K$\\alpha$ line on the physical parameters of AGN, such as the black hole mass $M_{BH}$, accretion rate (equivalently represented by Eddington ratio $\\lambda_{Edd}$), and optical classification, is investigated by applying the X-ray spectra stacking method to a large sample of AGN which have well measured optical parameters. A broad line feature is detected ($>3\\sigma$) in the stacked spectra of the high $\\lambda_{Edd}$ sub-sample ($\\log\\lambda_{Edd}>-0.9$). The profile of the broad line can be well fitted with relativistic broad line model, with the line energy consistent with highly ionized Fe K$\\alpha$ line (i.e. Fe xxvi). A model consisting of multiple narrow lines cannot be ruled out, however. We found hints that the Fe K line becomes broader as the $\\lambda_{Edd}$ increases. No broad line feature is shown in the sub-sample of broad-line Seyfert 1 (BLS1) galaxies and in the full sample, while a broad line might be present, though at low significance, in the su...

  14. Reducing PAH emissions from the iron ore sintering process by optimizing its operation parameters.

    Science.gov (United States)

    Chen, Yu-Cheng; Tsai, Perng-Jy; Mou, Jin-Luh

    2009-06-15

    This study set out to reduce polycyclic aromatic hydrocarbon (PAH) emissions from the iron ore sintering process by optimizing its operation parameters obtained from the Taguchi experimental design. Four operating parameters, including the water content (Wc; range = 6.0-7.0 wt %), suction pressure (Ps; range = 1000-1400 mmH2O), bed height (Hb; range = 500-600 mm), and type of hearth layer (HL; including sinter, hematite, and limonite) were selected and conducted on a pilot-scale sinter pot to simulate various sintering operating conditions of a real-scale sinter plant. We found that the resultant optimal combination (Wc = 6.5 wt %, Hb = 600 mm, Ps = 1400 mmH2O, and HL = limonite) could reduce the emission factor of total BaP equivalent concentration (EF(BaPeq)) up to 57.6% in comparison with the current operating condition of a real-scale sinter plant (Wc = 6.5 wt %, Hb = 550 mm, Ps = 1200 mmH2O, and HL = sinter). Through the ANOVA analysis, we found that Ps and Hb were the top two parameters affecting total EF(BaPeq) (accounting, respectively, for 70.9% and 21.2% of the total contribution of the four selected parameters). By examining both the sinter productivity and sinter strength, the values obtained from the optimal combination were quite comparable to those of the current operating condition. The above results further confirm the applicability of the obtained optimal combination for the real-scale sinter plant.

  15. Observation of iron spin-states using tabletop x-ray emission spectroscopy and microcalorimeter sensors

    Science.gov (United States)

    Joe, Y. I.; O'Neil, G. C.; Miaja-Avila, L.; Fowler, J. W.; Jimenez, R.; Silverman, K. L.; Swetz, D. S.; Ullom, J. N.

    2016-01-01

    X-ray emission spectroscopy (XES) is a powerful probe of the electronic and chemical state of elemental species embedded within complex compounds. X-ray sensors that combine high resolving power and high collecting efficiency are desirable for photon-starved XES experiments such as measurements of dilute, gaseous, and radiation-sensitive samples, time-resolved measurements, and in-laboratory XES. To assess whether arrays of cryogenic microcalorimeters will be useful in photon-starved XES scenarios, we demonstrate that these emerging energy-dispersive sensors can detect the spin-state of 3d electrons of iron in two different compounds, Fe2O3 and FeS2. The measurements were conducted with a picosecond pulsed laser-driven plasma as the exciting x-ray source. The use of this tabletop source suggests that time-resolved in-laboratory XES will be possible in the future. We also present simulations of {{K}}α and {{K}}β spectra that reveal the spin-state sensitivity of different combinations of sensor resolution and accumulated counts. These simulations predict that our current experimental apparatus can perform time-resolved XES measurements on some samples with a measurement time of a few 10 s of hours per time delay.

  16. A comprehensive emission inventory of multiple air pollutants from iron and steel industry in China: Temporal trends and spatial variation characteristics.

    Science.gov (United States)

    Wang, Kun; Tian, Hezhong; Hua, Shenbing; Zhu, Chuanyong; Gao, Jiajia; Xue, Yifeng; Hao, Jiming; Wang, Yong; Zhou, Junrui

    2016-07-15

    China has become the largest producer of iron and steel throughout the world since 1996. However, as an energy-and-pollution intensive manufacturing sector, a detailed comprehensive emission inventory of air pollutants for iron and steel industry of China is still not available. To obtain and better understand the temporal trends and spatial variation characteristics of typical hazardous air pollutants (HAPs) emissions from iron and steel production in China, a comprehensive emission inventory of multiple air pollutants, including size segregated particulate matter (TSP/PM10/PM2.5), gaseous pollutants (SO2, NOx, CO), heavy metals (Pb, Cd, Hg, As, Cr, Ni etc.), as well as the more dangerous PCDD/Fs, is established with the unit-based annual activity, specific dynamic emission factors for the historical period of 1978-2011, and the future potential trends till to 2050 are forecasted by using scenario analysis. Our results show that emissions of gaseous pollutants and particulate matter have experienced a gradual increase tendency since 2000, while emissions of priority-controlled heavy metals (Hg, Pb, As, Cd, Cr, and Ni) have exhibited a short-term fluctuation during the period of 1990 to 2005. With regard to the spatial distribution of HAPs emissions in base year 2011, Bohai economic circle is identified as the top emission intensity region where iron and steel smelting plants are densely built; within iron and steel industry, blast furnaces contribute the majority of PM emissions, sinter plants account for most of gaseous pollutants and the majority of PCDD/Fs, whereas steel making processes are responsible for the majority of heavy metal emissions. Moreover, comparisons of future emission trends under three scenarios indicate that advanced technologies and integrated whole process management strategies are in great need to further diminish various hazardous air pollutants from iron and steel industry in the future.

  17. [Emission characteristics of PM2.5 from blast furnace iron making].

    Science.gov (United States)

    Fan, Zhen-zhen; Zhao, Ya-li; Zhao, Hao-ning; Liang, Xing-yin; Sun, Jing-wen; Wang, Bao-gui; Wang, Ya-jun

    2014-09-01

    Electrical low pressure impactor (ELPI) was used to online analyze the PM2.5 particle size and mass concentration distribution in the trapping field and ore tank of blast furnace iron-making plant. Results showed that the grain number concentration of PM2.5 in trapping field after dust removal was in the range of 10(5)-10(6)cm-3 , and the particle size was mainly below 0. 1 μm. While the grain number concentration of the PM2.5 in ore tank after dust removal was in the range of 10(4)-10(5) cm-3, the particle size was mainly below 1.0 μm, and the mass concentration distribution showed a single peak. The micro-morphology of PM2.5 monomer was mainly divided into two categories, spherical particles and irregular aggregates. Chemical composition analysis indicated that the concentrations of water soluble SO(2-)(4) , K+ , Ca2+ were higher than other ions in PM2.5, with the percentage of 10. 32% -28.55% , 10. 36% -12. 15% , 3.97% -15. 4% , respectively. The major elements was Fe, Si, Al, with 16. 8% -31. 62% , 2. 24% -8.76% , 1.24% -5. 89% of total mass, respectively; organic carbon and elementary carbon were 2. 7% -4. 6% and 0. 8% -1. 3% , respectively. The emission factors of PM2.5 in trapping field and in ore tank after dust removal were ranged from 0.045 to 0.085 kg t(-1) and 0.042 to 0.071 kg t-1, respectively.

  18. A K-alpha x-ray source using high energy and high repetition rate laser system for phase contrast imaging

    OpenAIRE

    Serbanescu, Cristina; Fourmaux, Sylvain; Kieffer, Jean-Claude; Kincaid, Russell; Krol, Andrzej

    2009-01-01

    K-alpha x-ray sources from laser produced plasmas provide completely new possibilities for x-ray phase-contrast imaging applications. By tightly focusing intense femtosecond laser pulses onto a solid target K-alpha x-ray pulses are generated through the interaction of energetic electrons created in the plasma with the bulk target. In this paper, we present a continuous and efficient Mo K-alpha x-ray source produced by a femtosecond laser system operating at 100 Hz repetition rate with maximum...

  19. Thermal Iron K and Alpha: Line Emission from the X-Ray Binary GX 339-4

    Science.gov (United States)

    Xu, Y. D.; Zhang, S. N.; Zhang, X. L.; Liu, D. B.; Chen, L.; Xu, H. G.; You, J. H.

    2003-01-01

    The accretion rate of the black hole candidate X-ray binary GX 339-4 in the 'off' state is low, and an advection dominated accretion flow (ADAF) is present. Hydrogen-like and helium-like iron Kbalpha; emission lines at 6.7 and 6.95 keV from hot plasma of ADAF can be produced by recombination-cascade processes with moderately high intensities, which are markedly distinguished from the fluorescent iron Kα line at approximately 6.4 keV. We show that the observational features of GX 339-4 can be explained by the ADAF model, if the iron abundance is more than 10 times the solar value, though the reason for such a high abundance is still unclear. We suggest that the increase of the accretion rate makes GX 339-4 change from off, low, intermediate, to high and very high states, and the line center of iron Kbalpha; will therefore shift from approximately 6.83 to approximately 6.4 keV, i.e. to the fluorescent disc-line, since the disappearance of the ADAF due to its high accretion rate.

  20. Discovery Of Transient Iron Fluorescence In The Bare Seyfert Ark 120

    Science.gov (United States)

    Nardini, Emanuele; Porquet, D.; Reeves, J.; Braito, V.; Lobban, A.; Matt, G.

    2016-10-01

    We present the results from an X-ray observational campaign on the bare Seyfert galaxy Ark 120 jointly carried out with XMM- Newton, Chandra, and NuSTAR. The favourable line of sight to this source, devoid of any significant absorbing material, provides an incomparably clean view to the nuclear regions of an AGN, down to the the immediate surroundings of the radiatively efficient, accreting supermassive black hole. Here we focus on the nature, properties, and variability of the emission-line complex due to iron fluorescence detected in the 6-7 keV band. The narrow K-alpha feature from neutral iron at 6.4 keV is resolved by Chandra/HETG to a width of 5000 km/s, consistent with origin from the optical broad-line region. However, excess components are seen on both sides of this core. The excess emission map computed over the 7.5 days of XMM-Newton monitoring and the following, time-resolved spectral analysis show that both the red and blue features are highly variable on timescales of 10-15 hours. Any explanation (orbiting hotspots, coronal clumps, disc instabilities) requires a highly dynamic, inhomogeneous disc/coronal system. These observations thus prove the unique potential of a bare source like Ark 120 to better understand the physics of the accretion disc/X-ray corona system in AGN.

  1. Emerging Energy-efficiency and Carbon Dioxide Emissions-reduction Technologies for the Iron and Steel Industry

    Energy Technology Data Exchange (ETDEWEB)

    Hasanbeigi, Ali [Lawrence Berkeley National Lab. (LBNL), Berkeley, CA (United States). Energy Analysis and Environmental Impacts Dept.. China Energy Group; Price, Lynn [Lawrence Berkeley National Lab. (LBNL), Berkeley, CA (United States). Energy Analysis and Environmental Impacts Dept.. China Energy Group; Arens, Marlene [Fraunhofer Inst. for Systems and Innovation Research (ISI), Karlsruhe (Germany)

    2013-01-31

    Iron and steel manufacturing is among the most energy-intensive industries and accounts for the largest share, approximately 27 percent, of global carbon dioxide (CO2) emissions from the manufacturing sector. The ongoing increase in world steel demand means that this industry’s energy use and CO2 emissions continue to grow, so there is significant incentive to develop, commercialize and adopt emerging energy-efficiency and CO2 emissions-reduction technologies for steel production. Although studies from around the world have identified a wide range of energy-efficiency technologies applicable to the steel industry that have already been commercialized, information is limited and/or scattered regarding emerging or advanced energy-efficiency and low-carbon technologies that are not yet commercialized. This report consolidates available information on 56 emerging iron and steel industry technologies, with the intent of providing a well-structured database of information on these technologies for engineers, researchers, investors, steel companies, policy makers, and other interested parties. For each technology included, we provide information on energy savings and environmental and other benefits, costs, and commercialization status; we also identify references for more information.

  2. Assessment of Energy Efficiency Improvement and CO2 Emission Reduction Potentials in India's Iron and Steel Industry

    Energy Technology Data Exchange (ETDEWEB)

    Morrow, III, William R. [Lawrence Berkeley National Lab. (LBNL), Berkeley, CA (United States); Hasanbeigi, Ali [Lawrence Berkeley National Lab. (LBNL), Berkeley, CA (United States); Sathaye, Jayant [Lawrence Berkeley National Lab. (LBNL), Berkeley, CA (United States); Xu, Tengfang [Lawrence Berkeley National Lab. (LBNL), Berkeley, CA (United States)

    2012-12-03

    India’s 2010 annual crude steel production was 68 Mt which accounted for nearly five percent of the world’s annual steel production in the same year. In 2007, roughly 1600 PJ were consumed by India’s iron and steel industry to produce 53 Mt of steel. We identified and analyzed 25 energy efficiency technologies and measures applicable to the processes in the Indian iron and steel industry. The Conservation Supply Curve (CSC) used in this study is an analytical tool that captures both the engineering and the economic perspectives of energy conservation. Using a bottom-up electricity CSC model and compared to an electricity price forecast the cumulative plant-level cost-effective electricity savings potential for the Indian iron and steel industry for 2010-2030 is estimated to be 66 TWh, and the cumulative plant-level technical electricity saving potential is only slightly greater than 66 TWh for the same period. The primary energy related CO2 emissions reduction associated with cost-effective electricity savings is 65 Mt CO2. Compared to a fuel price forecast, an estimated cumulative cost-effective fuel savings potential of 768 PJ with associated CO2 emission reduction of 67 Mt CO2 during 2010-2030 is possible. In addition, a sensitivity analysis with respect to the discount rate used is conducted to assess the effect of changes in this parameter on the results. The result of this study gives a comprehensive and easy to understand perspective to the Indian iron and steel industry and policy makers about the energy efficiency potential and its associated cost.

  3. Polycyclic aromatic hydrocarbon emission profiles and removal efficiency by electrostatic precipitator and wetfine scrubber in an iron ore sintering plant

    Energy Technology Data Exchange (ETDEWEB)

    Ettore Guerriero; Antonina Lutri; Rosanna Mabilia; Maria Concetta Tomasi Sciano; Mauro Rotatori [Istituto sull' Inquinamento Atmosferico, Monterotondo Scalo (Italy). Consiglio Nazionale delle Ricerche

    2008-11-15

    A monitoring campaign of polychlorinated dibenzo-p-dioxins and dibenzofurans, polyaromatic hydrocarbons (PAHs), and polychlorinated biphenyl was carried out in an Italian iron ore sintering plant by sampling the combustion gases at the electrostatic precipitator (ESP) outlet, at the Wetfine scrubber (WS) outlet, and by collecting the ESP dust. Few data are available on these micropollutants produced in iron ore sintering plants, particularly from Italian plants. This study investigates the PAH emission profiles and the removal efficiency of ESPs and WS. PAHs were determined at the stack, ESP outlet flue gases, and in ESP dust to characterize the emission profiles and the performance of the ESP and the WS for reducing PAH emission. The 11 PAHs monitored are listed in the Italian legislative decree 152/2006. The mean total PAH sum concentration in the stack flue gases is 3.96 {mu}g/N m{sup 3}, in ESP outlet flue gases is 9.73 {mu}g/N m{sup 3}, and in ESP dust is 0.53 {mu}g/g. Regarding the emission profiles, the most abundant compound is benzo(b)fluoranthene, which has a relative low BaP toxic equivalency factors (TEF) value, followed by dibenzo(a,l)pyrene, which has a very high BaP(TEF) value. The emission profiles in ESP dust and in the flue gases after the ESP show some changes, whereas the fingerprint in ESP and stack flue gases is very similar. The removal efficiency of the ESP and of WS on the total PAH concentration is 5.2 and 59.5%, respectively. 2 figs., 5 tabs.

  4. PCDD/F and "Dioxin-like" PCB emissions from iron ore sintering plants in the UK.

    Science.gov (United States)

    Aries, Eric; Anderson, David R; Fisher, Raymond; Fray, Trevor A T; Hemfrey, Derek

    2006-11-01

    Investigations have been carried out at the three Corus UK sinter plants over the period 2002-2004 to characterise the emissions of both 2,3,7,8-PCDD/Fs and WHO-12 PCBs, to estimate annual mass releases of these organic micro-pollutants using the I-TEF and WHO-TEF schemes, and to investigate the formation of PCBs in the iron ore sintering process. Results showed that the sintering of iron ore produces a characteristic WHO-12 PCB and PCDD/F congener pattern that is substantially the same for all UK sinter plants. With regard to WHO-12 PCBs, the most abundant congeners were typically PCBs 118 (6-9 ngNm(-3)), 105 (2-4 ngNm(-3)) and 77 (2-3 ngNm(-3)). All other WHO-12 PCBs were also detected at concentrations around 1 ngNm(-3). All sinter plants investigated exhibited very similar TEQ concentrations. WHO-12 PCB emissions were in the range 0.042-0.111 ngWHO-TEQNm(-3), whereas PCDD/F emissions ranged from 0.39 to 1.62 ngWHO-TEQNm(-3). PCDF congeners were the main contributors to the overall TEQ in sintering emissions (ca. 85%). Amongst WHO-12 PCBs, PCB 126 was the only noteworthy contributor to total TEQ (ca. 5-7%), a similar contribution to that from PCDDs. Based on the measurements that Corus UK has undertaken at these three sinter plants, annual mass releases of WHO-12 PCBs and PCDD/Fs have been calculated. For UK sinter plants, a total mass release of 29.5 g WHO-TEQ per annum [WHO-12 PCBs+PCDD/Fs] has been estimated, representing 9% of the total PCDD/F emissions to the UK atmosphere. Measurements were also carried out at a UK sinter plant to determine the windleg emission profile of WHO-12 PCBs. Results showed that WHO-12 PCBs were formed in the same regions of the sinter strand as 2,3,7,8-PCDD/Fs, indicating that there was a strong correlation between the formation of WHO-12 PCBs and PCDD/Fs in the iron ore sintering process.

  5. Study on Emission Spectral Lines of Iron, Fe in Laser-Induced Breakdown Spectroscopy (LIBS) on Soil Samples

    Science.gov (United States)

    Idris, Nasrullah; Lahna, Kurnia; Fadhli; Ramli, Muliadi

    2017-05-01

    In this work, LIBS technique has been used for detection of heavy metal especially iron, Fe in soil sample. As there are a large number of emission spectral lines due to Fe and other constituents in soil, this study is intended to identify emission spectral lines of Fe and finally to find best fit emission spectral lines for carrying out a qualitative and quantitative analysis. LIBS apparatus used in this work consists of a laser system (Neodymium Yttrium Aluminum Garnet, Nd-YAG: Quanta Ray; LAB SERIES; 1,064 nm; 500 mJ; 8 ns) and an optical multichannel analyzer (OMA) system consisting of a spectrograph (McPherson model 2061; 1,000 mm focal length; f/8.6 Czerny- Turner) and an intensified charge coupled device (ICCD) 1024x256 pixels (Andor I*Star). The soil sample was collected from Banda Aceh city, Aceh, Indonesia. For spectral data acquisition, the soil sample has been prepared by a pressing machine in the form of pellet. The laser beam was focused using a high density lens (f=+150 mm) and irradiated on the surface of the pellet for generating luminous plasma under 1 atmosphere of air surrounding. The plasma emission was collected by an optical fiber and then sent to the optical multichannel analyzer (OMA) system for acquisition of the emission spectra. It was found that there are many Fe emission lines both atomic lines (Fe I) and ionic lines (Fe II) appeared in all detection windows in the wavelength regions, ranging from 200 nm to 1000 nm. The emission lines of Fe with strong intensities occurs together with emission lines due to other atoms such as Mg, Ca, and Si. Thus, the identification of emission lines from Fe is complicated by presence of many other lines due to other major and minor elements in soil. Considering the features of the detected emission lines, several emission spectral lines of Fe I (atomic emission line), especially Fe I 404.58 nm occurring at visible range are potential to be good candidate of analytical lines in relation to detection

  6. An innovative approach to sampling complex industrial emissions for use in animal toxicity tests: application to iron casting operations.

    Science.gov (United States)

    Palmer, W G; Scholz, R C; Moorman, W J

    1983-03-01

    Sampling of complex mixtures of airborne contaminants for chronic animal toxicity tests often involves numerous sampling devices, requires extensive sampling time, and yields forms of collected materials unsuitable for administration to animals. A method is described which used a high volume, wet venturi scrubber for collection of respirable fractions of emissions from iron foundry casting operations. The construction and operation of the sampler are presented along with collection efficiency data and its application to the preparation of large quantities of samples to be administered to animals by intratracheal instillation.

  7. Revealing the High Energy Emission from the Obscured Seyfert Galaxy MCG -5-23-16 with Suzaku

    CERN Document Server

    Reeves, J N; Dewangan, G C; Fabian, A C; Fukazawa, Y; Gallo, L; Griffiths, R; Inoue, H; Kunieda, H; Markowitz, A; Miniutti, G; Mizuno, T; Mushotzky, R; Okajima, T; Ptak, A; Takahashi, T; Terashima, Y; Ushio, M; Watanabe, S; Yamasaki, T; Yamauchi, M; Yaqoob, T; Reeves, James N.; Awaki, Hisamitsu; Dewangan, Gulab C.; Fabian, Andy C.; Fukazawa, Yasushi; Gallo, Luigi; Griffiths, Richard; Inoue, Hajime; Kunieda, Hideyo; Markowitz, Alex; MiniuttI, Giovanni; Mizuno, Tsunefumi; Mushotzky, Richard; Okajima, Takashi; Ptak, Andy; Takahashi, Tadayuki; Terashima, Yuichi; Ushio, Masayoshi; Watanabe, Shin; Yamasaki, Tomonori; Yamauchi, Makoto; Yaqoob, Tahir

    2006-01-01

    We report on a 100 ks Suzaku observation of the bright, nearby (z=0.008486) Seyfert 1.9 galaxy MCG -5-23-16. The broad-band (0.4-100 keV) X-ray spectrum allows us to determine the nature of the high energy emission with little ambiguity. The X-ray continuum consists of a cutoff power-law of photon index $\\Gamma=1.9$, absorbed through Compton-thin matter of column density $N_{\\rm H}=1.6\\times10^{22}$ cm$^{-2}$. A soft excess is observed below 1 keV and is likely a combination of emission from scattered continuum photons and distant photoionized gas. The iron K line profile is complex, showing narrow neutral iron K$\\alpha$ and K$\\beta$ emission, as well as a broad line which can be modeled by a moderately inclined accretion disk. The line profile shows either the disk is truncated at a few tens of gravitational radii, or the disk emissivity profile is relatively flat. A strong Compton reflection component is detected above 10 keV, which is best modeled by a combination of reflection off distant matter and the a...

  8. Low CO{sub 2} emission technologies for iron and steelmaking as well as titania slag production

    Energy Technology Data Exchange (ETDEWEB)

    Orth, A.; Anastasijevic, N.; Eichberger, H. [Outokumpu Technol GmbH, Oberursel (Germany)

    2007-08-15

    Outokumpu Technology has developed direct reduction technologies that allow in combination with smelting reduction processes or electric arc furnaces a substantial lowering of CO{sub 2} emissions. In this paper three examples are given: The Circofer process, already demonstrated in pilot plant scale, uses coal as reductant in a two stage CFB (circulating fluidized bed)/FB (fluidized bed) reactor configuration to obtain a highly metallized product suitable for charging into smelting processes. One possible application of Circofer is, in a single stage configuration, as prereduction unit in combination with HIsmelt a smelting reduction technology to produce hot metal using iron ore and coal fines. Using Circofer as prereduction step, the capacity of a given HIsmelt installation can be increased by the factor three to four compared to cold feed and CO, emission can be lowered to values about 20% below the standard of a modern blast furnace, as this combination of technologies requires no agglomeration plant or coke ovens. A second application of Circofer is the combination with an electric arc furnace (EAF) to produce steel directly from direct reduced iron (DRI). Charging hot DRI into an EAF decreases drastically electric power consumption and thus further lowers CO, emission. Applying Circosmelt, the combination of a single stage Circofer system with an electric reduction furnace for ilmenite processing, only half of the electric power consumption required today for titania slag production using cold, unreduced feed material is required. A common additional advantage of all Circofer based routes is that a 99% pure CO{sub 2} stream is removed for process reasons from the process gas and can be used for enhanced crude oil production or sequestration methods.

  9. XMM-Newton observation of the Seyfert 1.8 ESO 113-G010: discovery of a highly redshifted iron line at 5.4 keV

    CERN Document Server

    Porquet, D; Uttley, P; Turner, T J

    2004-01-01

    We present a spectral analysis of the Seyfert 1.8 ESO 113-G010 observed with XMM-Newton for 4 ks. The spectrum shows a soft excess below 0.7 keV and more interestingly a narrow emission Gaussian line at 5.4 keV (in its rest-frame), most probably originating from a redshifted iron Kalpha line. No significant line at or above 6.4 keV is found contrary to other objects showing redshifted lines, ruling out a strong blue-wing to the line profile. The line is detected at 99% confidence, from performing Monte Carlo simulations which fully account for the range of energies where a narrow iron line is likely to occur. The energy of the line could indicate emission from relativistic (0.17 - 0.23 c) ejected matter moving away from the observer, as proposed for Mrk 766 by Turner et al. (2004). Alternatively, the emission from a narrow annulus at the surface of the accretion disk.

  10. An extreme, blueshifted iron line profile in the Narrow Line Seyfert 1 PG 1402+261; an edge-on accretion disk or highly ionized absorption?

    CERN Document Server

    Reeves, J N; Turner, T J

    2004-01-01

    We report on a short XMM-Newton observation of the radio-quiet Narrow Line Seyfert 1 PG 1402+261. The EPIC X-ray spectrum of PG 1402+261 shows a strong excess of counts between 6-9 keV in the rest frame. This feature can be modeled by an unusually strong (equivalent width 2 keV) and very broad (FWHM velocity of 110000 km/s) iron K-shell emission line. The line centroid energy at 7.3 keV appears blue-shifted with respect to the iron Kalpha emission band between 6.4-6.97 keV, while the blue-wing of the line extends to 9 keV in the quasar rest frame. The line profile can be fitted by reflection from the inner accretion disk, but an inclination angle of >60 deg is required to model the extreme blue-wing of the line. Furthermore the extreme strength of the line requires a geometry whereby the hard X-ray emission from PG 1402+261 above 2 keV is dominated by the pure-reflection component from the disk, while little or none of the direct hard power-law is observed. Alternatively the spectrum above 2 keV may instead b...

  11. Solution structure of BmKalphaIT01, an alpha-insect toxin from the venom of the Chinese scorpion Buthus martensii Karsch.

    Science.gov (United States)

    Tong, Xiaotian; Zhu, Jing; Ma, Yuguang; Chen, Xiang; Wu, Gong; He, Fahu; Cao, Chunyang; Wu, Houming

    2007-10-09

    The solution structure of an alpha-insect toxin from Buthus martensii Karsch, BmKalphaIT01, has been determined by two-dimensional NMR spectroscopy and molecular modeling techniques. Combining the sequence homology comparison and toxicity bioassays, BmKalphaIT01 has been suggested to be a natural mutant of alpha-insect toxins and so can serve as a tool to study the relationship of structure-function among this group of toxins. The overall structure of BmKalphaIT01 shares a common core structure consisting of an alpha-helix packed against a three-stranded antiparallel beta-sheet, which exhibits distinctive local conformations within the loops connecting these secondary structure elements. The solution structure of BmKalphaIT01 features a non-proline cis peptide bond between Asn9 and Tyr10, which is proposed to mediate the spatial closing of the five-residue turn (Gln8-Cys12) and the C-terminal segment (Arg58-His64) to form the NC domain and confer the toxin insect-specific bioactivity. Conformational heterogeneity is observed in the solution of BmKalphaIT01 and could be attributed to the cis-trans isomerization of the peptide bond between residues 9 and 10. The minor conformation of BmKalphaIT01 with a trans peptide bond between Asn9 and Tyr10 may be responsible for its moderate bioactivity against mammals. The cis-trans isomerization of the peptide bond between residues 9 and 10 may be the structural basis of dual pharmacological activities of alpha-insect and alpha-like scorpion toxins, which is supported by the fact that conformational heterogeneity occurs in the solution structures of LqhalphaIT, LqqIII, and LqhIII and by comparison of the solution structure of BmKalphaIT01 with those of some relevant alpha-type toxins.

  12. Nutrients removal and nitrous oxide emission during simultaneous nitrification, denitrification, and phosphorus removal process: effect of iron.

    Science.gov (United States)

    Jia, Wenlin; Wang, Qian; Zhang, Jian; Yang, Weihua; Zhou, Xiaowei

    2016-08-01

    The short- and long-term influences of ferric iron (Fe(III)) on nutrients removal and nitrous oxide (N2O) emission during SNDPR process were evaluated. According to the continuous cycle experiments, it was concluded that the addition of Fe(III) could lower the nitrogen removal of the following cycle during SNDPR process, which was mainly induced by the chemical removal of phosphorus. However, the impacts were transitory, and simultaneous nitrogen and phosphorus removal would recover from the inhibition of Fe(III) after running certain cycles. Moreover, the addition of Fe(III) could stimulate N2O emission transitorily during SNDPR process. However, if Fe(III) was added into reactor continuously, the nitrogen removal would be improved, especially at low Fe load condition. It was because that the activity of NO reductase was enhanced by the addition of Fe. However, the low Fe load in reactor would induce more N2O emission. When Fe(III) load was 40 mg/L in the reactor, the N2O yield was 10 % higher than control. The TN removal was weakened when Fe(III) load reached to 60 mg/L, and the N2O yield was lower than control, due to the inhibition of the high Fe load on denitrification enzymes.

  13. Variation of the X-ray non-thermal emission in the Arches cloud

    CERN Document Server

    Clavel, Maïca; Terrier, R; Tatischeff, V; Maurin, G; Ponti, G; Goldwurm, A; Decourchelle, A

    2014-01-01

    The origin of the iron fluorescent line at 6.4 keV from an extended region surrounding the Arches cluster is debated and the non-variability of this emission up to 2009 has favored the low-energy cosmic-ray origin over a possible irradiation by hard X-rays. By probing the variability of the Arches cloud non-thermal emission in the most recent years, including a deep observation in 2012, we intend to discriminate between the two competing scenarios. We perform a spectral fit of XMM-Newton observations collected from 2000 to 2013 in order to build the Arches cloud lightcurve corresponding to both the neutral Fe Kalpha line and the X-ray continuum emissions. We reveal a 30% flux drop in 2012, detected with more than 4 sigma significance for both components. This implies that a large fraction of the studied non-thermal emission is due to the reflection of an X-ray transient source.

  14. A Suzaku Observation of the Low-Ionization Fe-Line Emission from RCW 86

    CERN Document Server

    Ueno, M; Kataoka, J; Bamba, A; Harrus, I; Hiraga, J; Hughes, J P; Kilbourne, C A; Koyama, K; Kokubun, M; Nakajima, H; Ozaki, M; Petre, R; Takahashi, T; Tanaka, T; Tomida, H; Yamaguchi, H; Ueno, Masaru; Sato, Rie; Kataoka, Jun; Bamba, Aya; Harrus, Ilana; Hiraga, Junko; Hughes, John P.; Kilbourne, Caroline A.; Koyama, Katsuji; Kokubun, Motohide; Nakajima, Hiroshi; Ozaki, Masanobu; Petre, Robert; Takahashi, Tadayuki; Tanaka, Takaaki; Tomida, Hiroshi; Yamaguchi, Hiroya

    2006-01-01

    The newly operational X-ray satellite Suzaku observed the southwestern quadrant of the supernova remnant (SNR) RCW 86 in February 2006 to study the nature of the 6.4 keV emission line first detected with the Advanced Satellite for Cosmology and Astronomy (ASCA). The new data confirm the existence of the line, localizing it for the first time; most of the line emission is adjacent and interior to the forward shock and not at the locus of the continuum hard emission. We also report the first detection of a 7.1 keV line that we interpret as the K-beta emission from low-ionization iron. The Fe-K line features are consistent with a non-equilibrium plasma of Fe-rich ejecta with n_{e}t <~ 10^9 cm^-3 s and kT_{e} ~ 5 keV. This combination of low n_{e}t and high kT_{e} suggests collisionless electron heating in an SNR shock. The Fe K-alpha line shows evidence for intrinsic broadening, with a width of 47 (34--59) eV (99% error region). The difference of the spatial distributions of the hard continuum above 3 keV and...

  15. Molecular Dynamics Simulation of Porous Layer-enhanced Dislocation Emission and Crack Propagation in Iron Crystal

    Institute of Scientific and Technical Information of China (English)

    D. Li; F.Y. Meng; X.Q. Ma; L.J. Qiao; W.Y. Chu

    2011-01-01

    The internal stress induced by a porous layer or passive layer can assist the applied stress to promote dislocation emission and crack propagation, e.9. when the pipeline steel is buried in the soil containing water, resulting in stress corrosion cracking (SCC). Molecular dynamics (MD) simulation is performed to study the process of dislocation emission and crack propagation in a slab of Fe crystal with and without a porous layer on the surface of the crack. The results show that when there is a porous layer on the surface of the crack, the tensile stress induced by the porous layer can superimpose on the external applied stress and then assist the applied stress to initiate crack tip dislocation emission under lowered stress intensity KI, or stress. To respond to the corrosion accelerated dislocation emission and motion, the crack begins to propagate under lowered stress intensity KI, resulting in SCC.

  16. 钢铁生产CO2过程排放分析%Analysis of CO2 emissions of iron and steel making process

    Institute of Scientific and Technical Information of China (English)

    卢鑫; 白皓; 赵立华; 李宁; 李洪福

    2012-01-01

    钢铁生产成为大气中温室气体CO2的一大来源,准确测算钢铁生产CO2过程排放量是评估企业或行业减排的保障.建立基于CO2排放模块的CO2排放模型,选定国内典型钢铁生产企业进行分析,发现炼铁工序的CO2排放占总流程的60%左右,同时进一步分析了整体CO2排放强度与吨钢能耗的关系及工序CO2排放强度的分布.%The iron and steel making process has become one of the main sources of greenhouse gas CO2 in atmosphere, and the accurate calculation of CO2 emission in iron and steel making process will be the foundation to evaluate the emission reduction of specific enterprise and industry. With the CO2 emission model based on the CO2 emission module and the data from the selective typical iron and steel making plants in China, it was found that the CO2 emission of iron making process account for about 60% of total emission. Further, the relationship between total CO2 emission intensity and energy consumption intensity and the distribution of different process CO2 emission were analyzed.

  17. IronEmission Lines in Seyfert(-Like) Active Galactic Nuclei: Revelation of a Rapidly Spinning Central Black Hole

    Institute of Scientific and Technical Information of China (English)

    马振国

    2002-01-01

    Fe Kα lines are superimposed upon the x-ray continuum in most Seyfert(-like) active galactic nuclei (AGNs).By a data-fitting study, previous authors have claimed that the central black hole (BH) is either rotating ornon-rotating according to the thin disc model. We develop the disc model to the torus model to determine thereal spin of the BH. With formulations of the motion of both torus particles and photons near a BH in Kerrmetric, we simulate iron emission linesfrom a thin luminous torus. It is found that only spinning BH galaxiescan radiate observable profiles. The data-fitting to Fe lines of four AGNs observed by ASCA predicts that thecentral BH is spinning rapidly with the dimensionless specific angular momentum approaching the maximalvalueof 1.

  18. Iron line profiles including emission from within the innermost stable orbit of a black hole accretion disc

    CERN Document Server

    Young, A J; Fabian, A C

    1998-01-01

    Reynolds & Begelman (1997) have recently proposed a model in which the broad and extremely redshifted iron line seen during a deep minimum of the light curve of the Seyfert 1 galaxy MCG-6-30-15 originates from matter spiralling into a Schwarzschild black hole, contrary to previous claims that the black hole may be spinning rapidly (Iwasawa et al 1996; Dabrowski et al 1997). Here we calculate in detail the X-ray spectrum produced by their model using the full reflected continuum emission, including absorption features. This calculation takes into account the doppler and relativistic effects. For the range of parameters we consider, we find that the spectrum should show a large photoelectric absorption edge of iron, which is not seen in the data. The absorption edge is a consequence of the line emitting matter within the innermost stable orbit being highly ionized, and is largely independent of the parameters chosen for their model. If we restrict our attention to the 3-10 keV band we may effectively remove...

  19. Pharmacokinetics and red cell utilization of iron(III) hydroxide-sucrose complex in anaemic patients: a study using positron emission tomography.

    Science.gov (United States)

    Beshara, S; Lundqvist, H; Sundin, J; Lubberink, M; Tolmachev, V; Valind, S; Antoni, G; Långström, B; Danielson, B G

    1999-02-01

    The pharmacokinetics of a single intravenous injection of 100 mg iron hydroxide-sucrose complex labelled with a tracer in the form of 52Fe/59Fe was followed in six anaemic patients for a period ranging from 6 to 8 3 h using positron emission tomography (PET). Red cell utilization of the labelled iron was followed for 4 weeks. PET data showed radioactive uptake by the liver, spleen and bone marrow. The uptake by the macrophage-rich spleen demonstrated the reticuloendothelial uptake of this iron preparation, with subsequent effective release of that iron for marrow utilization. Red cell utilization, followed for 4 weeks, ranged from 59% to 97%. The bone marrow influx rate constant was independent of blood iron concentration, indicating non-saturation of the transport system in bone marrow. This implied that higher doses of the iron complex can probably be used in the same setting. A higher influx rate into the marrow compared with the liver seemed to be consistent with higher red cell utilization. This would indicate that early distribution of the injected iron complex may predict the long-term utilization.

  20. Standard practice for acoustic emission examination of cast iron yankee and steam heated paper dryers

    CERN Document Server

    American Society for Testing and Materials. Philadelphia

    2007-01-01

    1.1 This practice provides guidelines for carrying out acoustic emission (AE) examinations of Yankee and Steam Heated Paper Dryers (SHPD) of the type to make tissue, paper, and paperboard products. 1.2 This practice requires pressurization to levels used during normal operation. The pressurization medium may be high temperature steam, air, or gas. The dryer is also subjected to significant stresses during the heating up and cooling down periods of operation. Acoustic Emission data maybe collected during these time periods but this testing is beyond the scope of this document. 1.3 The AE measurements are used to detect, as well as, localize emission sources. Other methods of nondestructive testing (NDT) may be used to further evaluate the significance of acoustic emission sources. 1.4 This standard does not purport to address all of the safety concerns, if any, associated with its use. It is the responsibility of the user of this standard to establish appropriate safety and health practices and determine th...

  1. Field-scale spatial correlation between contents of iron oxides and CO2 emission in an Oxisol cultivated with sugarcane

    Directory of Open Access Journals (Sweden)

    Angélica Santos Rabelo de Souza Bahia

    2015-02-01

    Full Text Available Soil CO2 emission (FCO2 is one of the main sources of carbon release into the atmosphere. Moreover, FCO2 is related to soil attributes governing the transfer of gases from soil to the atmosphere. This study aimed firstly to describe the spatial variability of hematite (Hm, goethite (Gt, iron extracted with sodium dithionite-citrate-bicarbonate (Fed contents, soil CO2 emission (FCO2 and free-water porosity (FWP and secondly, to develop statistical models to predict the above mentioned factors in an Oxisol cultivated under manual harvesting of sugarcane (Saccharumspp. in southeastern Brazil. The study was conducted on an irregular 50 m × 50 m grid containing 89 points, each 0.5-10 m apart. The 0-0.1 m soil layer at each sampling point was used to assess soil FCO2, moisture and total pore volume. The results were subjected to descriptive statistical and geostatistical analyses using auto- and cross-semivariograms. All soil attributes exhibited a spatial dependence structure and the experimental semivariograms fitted spherical and exponential models. The Gt content was the individual attribute that exhibited the highest linear and spatial correlation, especially with FCO2. We were able to use diffuse reflectance spectroscopy to map large areas, which allows for easy identification and estimation of soil attributes such as FCO2 and FWP. Geostatistical techniques faciltate the interpretation of spatial relationships between soil respiration and the examined properties.

  2. Discovery of superstrong, fading, iron line emission and double-peaked Balmer lines of the galaxy SDSSJ0952+2143 - the light echo of a huge flare

    CERN Document Server

    Komossa, S; Wang, T; Ajello, M; Ge, J; Greiner, J; Lü, H; Salvato, M; Saxton, R; Shan, H; Xu, D; Yuan, W

    2008-01-01

    We report the discovery of superstrong, fading, high-ionization iron line emission in the galaxy SDSSJ095209.56+214313.3 (SDSSJ0952+2143 hereafter), which must have been caused by an X-ray outburst of large amplitude. SDSSJ0952+2143 is unique in its strong multiwavelength variability; such a broadband emission-line and continuum response has not been observed before. The strong iron line emission is accompanied by unusual Balmer line emission with a broad base, narrow core and double-peaked narrow horns, and strong HeII emission. These lines, while strong in the SDSS spectrum taken in 2005, have faded away significantly in new spectra taken in December 2007. Comparison of SDSS, 2MASS, GALEX and follow-up GROND photometry reveals variability in the NUV, optical and NIR band. Taken together, these unusual observations can be explained by a giant outburst in the EUV--X-ray band, detected even in the optical and NIR. The intense and variable iron, Helium and Balmer lines represent the ``light echo'' of the flare,...

  3. Solution structure of BmKalphaTx11, a toxin from the venom of the Chinese scorpion Buthus martensii Karsch.

    Science.gov (United States)

    Zhu, Jing; Tong, Xiaotian; Cao, Chunyang; Wu, Gong; Zhang, Naixia; Wu, Houming

    2010-01-01

    The solution structure of BmKalphaTx11 presented by this paper is distinctive from any other structures of wide-type scorpion alpha-toxins reported so far, for its trans-9,10 peptide bond conformation is accompanied by 'protruding' topology of the 'NC-domain'. The orientation of the C-tail of BmKalphaTx11 is obviously different from that of classical alpha-toxins (e.g., AaH2, BmK-M8), despite the fact that they share common trans conformation of peptide bond between residues 9 and 10. Accordingly, there must be other structural factors dominating the orientation of the C-tail except the conformation of peptide bond 9-10. Our study reveals that residues at position 58 play an important role in it, and different type of residues at this position (e.g., Lys, Arg, Met, Ile) result in different spatial relationship between the C-terminus and the 'five-residue-turn' and then different topology of the 'NC-domain', therefore residues at position 58 are believed to function as structure and bioactivity switch for specificity of scorpion alpha-toxins. The mechanism for stabilizing the geometry of the 'NC-domain' in wide-type scorpion alpha-toxins is also discussed.

  4. Enhanced Iron and Selenium Uptake in Plants by Volatile Emissions of Bacillus amyloliquefaciens (BF06

    Directory of Open Access Journals (Sweden)

    Jianfei Wang

    2017-01-01

    Full Text Available Volatile organic compounds (VOCs released by plant growth-promoting rhizobacteria (PGPR are involved in promoting growth and triggering systemic resistance (ISR in plants. Importantly, the release of VOCs by some PGPR strains confers improved plant uptake of nutrient elements from the soil. However, the underlying mechanisms of VOCs-regulated nutrient acquisition remain elusive. In this study, VOCs were extracted and identified from Bacillus amyloliquefaciens (strain BF06 using gas chromatography–mass spectrometry (GC–MS. BF06 VOCs exposure significantly promoted the growth and photosynthesis of Arabidopsis plants. To explore how microbial VOCs stimulate growth in plants, gene expression profiles of Arabidopsis seedlings exposed to BF06 VOCs were examined using transcriptomic analyses. In screening differentially expressed genes (DEGs, most upregulated DEGs were found to be related to amino acid transport, iron (Fe uptake and homeostasis, and sulfate transport. Furthermore, BF06 VOCs significantly enhanced Fe absorption in plants under Fe-limited conditions. However, when nitric oxide (NO synthesis was inhibited, BF06 VOCs exposure could not substantially augment Fe acquisition in plants under alkaline stress, indicating that VOCs-mediated plant uptake of Fe was required for induction of root NO accumulation. In addition, BF06 VOCs exposure led to a marked increase in some genes encoding for sulfate transporters, and further increased Se accumulation in plants. Intriguingly, BF06 VOCs exposure failed to increase Se uptake in sultr1;2 mutants, which may indicate that high-level transcription of these sulfate transporters induced by BF06 VOCs was essential for enhancing Se absorption by plants. Taken together, our results demonstrated the potential of VOCs released by this strain BF06 to increase Fe and Se uptake in plants.

  5. Characterization of polycyclic aromatic hydrocarbons in fugitive PM10 emissions from an integrated iron and steel plant.

    Science.gov (United States)

    Khaparde, V V; Bhanarkar, A D; Majumdar, Deepanjan; Rao, C V Chalapati

    2016-08-15

    Fugitive emissions of PM10 (particles blast furnace and steel manufacturing unit in an integrated iron and steel plant situated in India. Concentrations of PM10, PM10-bound total PAHs, benzo (a) pyrene, carcinogenic PAHs and combustion PAHs were found to be highest around the sintering unit. Concentrations of 3-ring and 4-ring PAHs were recorded to be highest in the coking unit whereas 5-and 6-ring PAHs were found to be highest in other units. The following indicatory PAHs were identified: indeno (1,2,3-cd) pyrene, dibenzo (a,h) anthracene, benzo (k) fluoranthene in blast furnace unit; indeno (1,2,3-cd) pyrene, dibenzo (a,h) anthracene, chrysene in sintering unit; Anthracene, fluoranthene, chrysene in coking unit and acenaphthene, fluoranthene, fluorene in steel making unit. Total-BaP-TEQ (Total BaP toxic equivalent quotient) and BaP-MEQ (Total BaP mutagenic equivalent quotient) concentration levels ranged from 2.4 to 231.7ng/m(3) and 1.9 to 175.8ng/m(3), respectively. BaP and DbA (dibenzo (a,h) anthracene) contribution to total-BaP-TEQ was found to be the highest.

  6. Broad iron emission line and kilohertz quasi-periodic oscillations in the neutron star system 4U 1636-53

    CERN Document Server

    Sanna, Andrea; Altamirano, Diego; Belloni, Tomaso; Hiemstra, Beike; Linares, Manuel

    2014-01-01

    Both the broad iron (Fe) line and the frequency of the kilohertz quasi-periodic oscillations (kHz QPOs) in neutron star low-mass X-ray binaries (LMXBs) can potentially provide independent measures of the inner radius of the accretion disc. We use XMM-Newton and simultaneous Rossi X-ray Timing Explorer observations of the LMXB 4U 1636-53 to test this hypothesis. We study the properties of the Fe-K emission line as a function of the spectral state of the source and the frequency of the kHz QPOs. We find that the inner radius of the accretion disc deduced from the frequency of the upper kHz QPO varies as a function of the position of the source in the colour-colour diagram, in accordance with previous work and with the standard scenario of accretion disc geometry. On the contrary, the inner disc radius deduced from the profile of the Fe line is not correlated with the spectral state of the source. The values of the inner radius inferred from kHz QPOs and Fe lines, in four observations, do not lead to a consisten...

  7. Emission of organic compounds from mould and core binders used for casting iron, aluminium and bronze in sand moulds.

    Science.gov (United States)

    Tiedje, Niels; Crepaz, Rudolf; Eggert, Torben; Bey, Niki

    2010-12-01

    Emissions from mould and core sand binders commonly used in the foundry industry have been investigated. Degradation of three different types of binders was investigated: Furfuryl alcohol (FA), phenolic urethane (PU) and resol-CO2 (RC). In each group of binders, at least two different binder compositions were tested. A test method that provides uniform test conditions is described. The method can be used as a general test method to analyse off gases from binders. Moulds, containing a standard size casting, were produced and the amount and type of organic compounds, resulting from thermal degradation of binders, was monitored when cast iron, bronze and aluminium was poured in the moulds. Binder degradation was measured by collecting off gases in a specially designed ventilation hood at a constant flow rate. Samples were taken from the ventilation system and analysed for hydrocarbons and CO content. It is shown how off-gases vary with time after pouring and shake out. Also the composition of off-gases is analysed and shown. It is further shown how the composition of off-gasses varies between different types of binders and with varying composition of the binders as well as function of the thermal load on the moulding sand.

  8. Testing the Kerr Nature of Black Hole Candidates using Iron Line Spectra in the CPR Framework

    CERN Document Server

    Jiang, Jiachen; Steiner, James F

    2015-01-01

    The iron K$\\alpha$ line commonly observed in the X-ray spectrum of both stellar-mass and supermassive black hole candidates originates from X-ray fluorescence of the inner accretion disk. Accordingly, it can be used to map the spacetime geometry around these objects. In this paper, we extend previous work using the iron K$\\alpha$ line to test the Kerr black hole hypothesis. We adopt the Cardoso-Pani-Rico parametrization and we test the possibility of constraining possible deviations from the Kerr solution that can be obtained from observations across the range of black hole spins and inclination angles. We confirm previous claims that the iron K$\\alpha$ line is potentially a quite powerful probe for testing the Kerr metric given sufficiently high quality data and with systematics under control, especially in the case of fast-rotating black holes and high inclination angles since both conditions serve to maximize relativistic effects. We find that some geometric perturbations from Kerr geometry manifest more s...

  9. Assessment of Energy Efficiency Improvement and CO2 Emission Reduction Potentials in the Iron and Steel Industry in China

    Energy Technology Data Exchange (ETDEWEB)

    Hasanbeigi, Ali [Lawrence Berkeley National Lab. (LBNL), Berkeley, CA (United States); Morrow, William [Lawrence Berkeley National Lab. (LBNL), Berkeley, CA (United States); Sathaye, Jayant [Lawrence Berkeley National Lab. (LBNL), Berkeley, CA (United States); Masanet, Eric [Lawrence Berkeley National Lab. (LBNL), Berkeley, CA (United States); Xu, Tengfang [Lawrence Berkeley National Lab. (LBNL), Berkeley, CA (United States)

    2012-05-15

    China’s annual crude steel production in 2010 was 638.7 Mt accounting for nearly half of the world’s annual crude steel production in the same year. Around 461 TWh of electricity and 14,872 PJ of fuel were consumed to produce this quantity of steel in 2010. We identified and analyzed 23 energy efficiency technologies and measures applicable to the processes in the iron and steel industry. The Conservation Supply Curve (CSC) used in this study is an analytical tool that captures both the engineering and the economic perspectives of energy conservation. Using a bottom-up electricity CSC model, the cumulative cost-effective electricity savings potential for the Chinese iron and steel industry for 2010-2030 is estimated to be 251 TWh, and the total technical electricity saving potential is 416 TWh. The CO2 emissions reduction associated with cost-effective electricity savings is 139 Mt CO2 and the CO2 emission reduction associated with technical electricity saving potential is 237 Mt CO2. The FCSC model for the iron and steel industry shows cumulative cost-effective fuel savings potential of 11,999 PJ, and the total technical fuel saving potential is 12,139. The CO2 emissions reduction associated with cost-effective and technical fuel savings is 1,191 Mt CO2 and 1,205 Mt CO2, respectively. In addition, a sensitivity analysis with respect to the discount rate used is conducted to assess the effect of changes in this parameter on the results. The result of this study gives a comprehensive and easy to understand perspective to the Chinese iron and steel industry and policy makers about the energy efficiency potential and its associated cost.

  10. A disk wind interpretation of the strong Fe K{\\alpha} features in 1H 0707-495

    CERN Document Server

    Hagino, Kouichi; Done, Chris; Tomaru, Ryota; Watanabe, Shin; Takahashi, Tadayuki

    2015-01-01

    1H 0707-495 is the most convincing example of a supermassive black hole with an X-ray spectrum being dominated by extremely smeared, relativistic reflection. However, here we show that the iron features in its 2--10 keV spectrum are rather similar to the archetypal wind dominated source, PDS 456. We fit all the 2--10 keV spectra from 1H 0707-495 using the same wind model as used for PDS 456, but viewed at higher inclination so that the iron absorption line is broader but not so blueshifted. This gives a good overall fit to the data from 1H 0707-495, and an extrapolation of this model to higher energies also gives a good match to the NuSTAR data. Small remaining residuals may indicate that the emission from the wind is stronger than in PDS 456, consistent with the wider angle wind expected from a continuum driven wind from the super-Eddington mass accretion rate in 1H 0707-495. We suggest that the spectrum of 1H 0707-495 is sculpted more by absorption in a wind than by extreme relativistic effects in strong gr...

  11. Discussion of "Normal Spectral Emissivity Measurement of Liquid Iron and Nickel Using Electromagnetic Levitation in Direct Current Magnetic Field."

    Science.gov (United States)

    Daun, Kyle J.

    2016-07-01

    This note corrects nonphysical Drude model parameters presented for molten iron and nickel. A comparison of the corrected Drude models with data published in the literature shows that a simple Drude form is inadequate to describe the optical properties of molten iron and nickel.

  12. A search for iron emission lines in the Chandra X-ray spectra of neutron star low-mass X-ray binaries

    CERN Document Server

    Cackett, E M; Homan, J; Van der Klis, M; Lewin, W H G; Méndez, M; Raymond, J; Steeghs, D; Wijnands, R

    2008-01-01

    While iron emission lines are well studied in black hole systems, both in X-ray binaries and Active Galactic Nuclei, there has been less of a focus on these lines in neutron star low-mass X-ray binaries (LMXBs). However, recent observations with Suzaku and XMM-Newton have revealed broad asymmetric iron line profiles in 4 neutron star LMXBs, confirming an inner disk origin for these lines in neutron star systems. Here, we present a search for iron lines in 6 neutron star LMXBs. For each object we have simultaneous Chandra and RXTE observations at 2 separate epochs, allowing for both a high resolution spectrum, as well as broadband spectral coverage. Out of the six objects in the survey, we only find significant iron lines in two of the objects, GX 17+2 and GX 349+2. However, we cannot rule out that there are weak, broad lines present in the other sources. The equivalent width of the line in GX 17+2 is consistent between the 2 epochs, while in GX 349+2 the line equivalent width increases by a factor of ~3 betwe...

  13. Spatial and Temporal Variations of the Diffuse Iron 6.4 keV Line in the Galactic Center Region

    CERN Document Server

    Chernyshov, D O; Nobukawa, M; Tsuru, T G; Koyama, K; Uchiyama, H; Matsumoto, H

    2011-01-01

    We analyze the diffuse Fe I K-alpha line generated in the diffuse interstellar molecular hydrogen by primary photons or subrelativistic protons injected by Sagittarius (Sgr) A*. We showed that unlike emission from compact molecular clouds, this emission can be permanently observed in the directions of the Galactic center. We conclude that the diffuse emission of 6.4 keV line observed at present is probably due to Fe I K-alpha vacancy production by primary photons if the X-ray luminosity of Sgr A* was about Lx ~ 10^39-10^40 erg/s. In principle these data can also be described in the framework of the model when the 6.4 keV line emission is generated by subrelativistic protons generated by accretion onto the central black hole but in this case extreme parameters of this model are necessary.

  14. 浅议碳排放与废钢铁的节能减排功效%Carbon emission and effect of energy-saving and emission-reducing of iron scrap

    Institute of Scientific and Technical Information of China (English)

    林加冲

    2012-01-01

    CO2 is the main cause of global warming and environmental deterioration. The situation of CO2 emission of iron and steel industry in the world was introduced. According to the current situation in China, the paper proposed it should develop iron scrap industry, and increase the supply capability of iron scrap, which is the main approach for iron industry to get out of crisis and realize low-carbon development and green development.%二氧化碳是导致全球气候变暖、人类生存环境恶化的主要原因。简要介绍世界钢铁工业二氧化碳排放情况,针对我国钢铁工业碳排放的具体情况,提出发展我国废钢产业,提高废钢铁的供应能力,是我国钢铁工业摆脱危机,实现低碳发展、绿色发展的主要途径。

  15. Kinetic analysis of 52Fe-labelled iron(III) hydroxide-sucrose complex following bolus administration using positron emission tomography.

    Science.gov (United States)

    Beshara, S; Lundqvist, H; Sundin, J; Lubberink, M; Tolmachev, V; Valind, S; Antoni, G; Långström, B; Danielson, B G

    1999-02-01

    Kinetic analysis of a single intravenous injection of 100 mg iron(III) hydroxide-sucrose complex (Venofer) mixed with 52Fe(III) hydroxide-sucrose as a tracer was followed for 3-6 h in four generally anaesthetized, artificially ventilated minipigs using positron emission tomography (PET). The amount of injected radioactivity ranged from 30 to 200 MBq. Blood radioactivity, measured by PET in the left ventricle of the heart, displayed a fast clearance phase followed by a slow one. In the liver and bone marrow a fast radioactivity uptake occurred during the first 30 min, followed by a slower steady increase. In the liver a slight decrease in radioactivity uptake was noted by the end of the study. A kinetic analysis using a three-compartment (namely blood pool, reversible and irreversible tissue pools) model showed a fairly high distribution volume in the liver as compared with the bone marrow. In conclusion, the pharmacokinetics of the injected complex was clearly visualized with the PET technique. The organs of particular interest, namely the heart (for blood kinetics), liver and bone marrow could all be viewed by a single setting of a PET tomograph with an axial field of view of 10 cm. The half-life (T1/2) of 52Fe (8.3 h) enables a detailed kinetic study up to 24 h. A novel method was introduced to verify the actual 52Fe contribution to the PET images by removing the interfering radioactive daughter 52mMn positron emissions. The kinetic data fitted the three-compartment model, from which rate constants could be obtained for iron transfer from the blood to a pool of iron in bone marrow or liver to which it was bound during the study period. In addition, there was a reversible tissue pool of iron, which in the liver slowly equilibrated with the blood, to give a net efflux from the liver some hours after i.v. administration. The liver uptake showed a relatively long distribution phase, whereas the injected iron was immediately incorporated into the bone marrow. Various

  16. Deviation from Boltzmann distribution in excited energy levels of singly-ionized iron in an argon glow discharge plasma for atomic emission spectrometry

    Energy Technology Data Exchange (ETDEWEB)

    Zhang Lei; Kashiwakura, Shunsuke; Wagatsuma, Kazuaki, E-mail: wagatuma@imr.tohoku.ac.jp

    2012-01-15

    A Boltzmann plot for many iron ionic lines having excitation energies of 4.7-9.1 eV was investigated in an argon glow discharge plasma when the discharge parameters, such as the voltage/current and the gas pressure, were varied. A Grimm-style radiation source was employed in a DC voltage range of 400-800 V at argon pressures of 400-930 Pa. The plot did not follow a linear relationship over a wide range of the excitation energy, but it yielded a normal Boltzmann distribution in the range of 4.7-5.8 eV and a large overpopulation in higher-lying excitation levels of iron ion. A probable reason for this phenomenon is that excitations for higher excited energy levels of iron ion would be predominantly caused by non-thermal collisions with argon species, the internal energy of which is received by iron atoms for the ionization. Particular intense ionic lines, which gave a maximum peak of the Boltzmann plot, were observed at an excitation energy of ca. 7.7 eV. They were the Fe II 257.297-nm and the Fe II 258.111-nm lines, derived from the 3d{sup 5}4s4p {sup 6}P excited levels. The 3d{sup 5}4s4p {sup 6}P excited levels can be highly populated through a resonance charge transfer from the ground state of argon ion, because of good matching in the excitation energy as well as the conservation of the total spin before and after the collision. An enhancement factor of the emission intensity for various Fe II lines could be obtained from a deviation from the normal Boltzmann plot, which comprised the emission lines of 4.7-5.8 eV. It would roughly correspond to a contribution of the charge transfer excitation to the excited levels of iron ion, suggesting that the charge-transfer collision could elevate the number density of the corresponding excited levels by a factor of ca.10{sup 4}. The Boltzmann plots give important information on the reason why a variety of iron ionic lines can be emitted from glow discharge plasmas.

  17. MCDF-RCI predictions for structure and width of $K\\alpha_{1,2}$ x-ray line of Al and Si

    CERN Document Server

    Kozioł, Karol

    2014-01-01

    Multiconfiguration Dirac-Fock and Relativistic Configuration Interaction methods have been employed to predict the structure and the width of $K\\alpha_{1,2}$ x-ray lines of Al and Si. The influences of electron correlation and inclusion of possible satellite contributions on spectra structure have been studied. The widths of $K$ and $L_{2,3}$ atomic levels of Al and Si have been also computed.

  18. Temperature sensitivity of Cu K(alpha) imaging efficiency using a spherical Bragg reflecting crystal

    Energy Technology Data Exchange (ETDEWEB)

    Akli, K U; Key, M H; Chung, H K; Hansen, S B; Freeman, R R; Chen, M H; Gregori, G; Hatchett, S; Hey, D; Izumi, N; King, J A; Kuba, J; Norreys, P; Mackinnon, A J; Murphy, C D; Snavely, R; Stepehens, R; Stoeckel, C; Theobald, W; Zhang, B

    2006-08-07

    The Vulcan laser facility at the Rutherford Appleton Laboratory was used to study the interaction of a 75 J 10 ps, high intensity laser beam with low-mass solid, Cu targets. Two instruments were fielded as diagnostics of the Cu K-shell emission from the targets: A single photon counting CCD spectrometer provided the absolute K{sub {alpha}} yield and a spherically bent Bragg crystal recorded 2D monochromatic images with a spatial resolution of 10 {micro}m. Due to the shifting and broadening of the K{sub {alpha}} spectral lines with increasing temperature, there is a temperature dependence of the crystal collection efficiency. This provides a temperature diagnostic when cross calibrated against a single hit CCD spectrometer, and it affects measurements of the spatial pattern of electron transport. The experimental data showing changing collection efficiency are presented. The results are discussed in light of modeling of the temperature-dependent spectrum of Cu K-shell emission.

  19. A frequent kinase domain mutation that changes the interaction between PI3K[alpha] and the membrane

    Energy Technology Data Exchange (ETDEWEB)

    Mandelker, Diana; Gabelli, Sandra B.; Schmidt-Kittler, Oleg; Zhu, Jiuxiang; Cheong, Ian; Huang, Chuan-Hsiang; Kinzler, Kenneth W.; Vogelstein, Bert; Amzel, L. Mario; (JHU-MED); (HHMI)

    2009-12-01

    Mutations in oncogenes often promote tumorigenesis by changing the conformation of the encoded proteins, thereby altering enzymatic activity. The PIK3CA oncogene, which encodes p110{alpha}, the catalytic subunit of phosphatidylinositol 3-kinase alpha (PI3K{alpha}), is one of the two most frequently mutated oncogenes in human cancers. We report the structure of the most common mutant of p110{alpha} in complex with two interacting domains of its regulatory partner (p85{alpha}), both free and bound to an inhibitor (wortmannin). The N-terminal SH2 (nSH2) domain of p85{alpha} is shown to form a scaffold for the entire enzyme complex, strategically positioned to communicate extrinsic signals from phosphopeptides to three distinct regions of p110{alpha}. Moreover, we found that Arg-1047 points toward the cell membrane, perpendicular to the orientation of His-1047 in the WT enzyme. Surprisingly, two loops of the kinase domain that contact the cell membrane shift conformation in the oncogenic mutant. Biochemical assays revealed that the enzymatic activity of the p110{alpha} His1047Arg mutant is differentially regulated by lipid membrane composition. These structural and biochemical data suggest a previously undescribed mechanism for mutational activation of a kinase that involves perturbation of its interaction with the cellular membrane.

  20. Using learning curves on energy-efficient technologies to estimate future energy savings and emission reduction potentials in the U.S. iron and steel industry

    Energy Technology Data Exchange (ETDEWEB)

    Karali, Nihan [Lawrence Berkeley National Lab. (LBNL), Berkeley, CA (United States); Park, Won Young [Lawrence Berkeley National Lab. (LBNL), Berkeley, CA (United States); McNeil, Michael A. [Lawrence Berkeley National Lab. (LBNL), Berkeley, CA (United States)

    2015-06-18

    Increasing concerns on non-sustainable energy use and climate change spur a growing research interest in energy efficiency potentials in various critical areas such as industrial production. This paper focuses on learning curve aspects of energy efficiency measures in the U.S iron and steel sector. A number of early-stage efficient technologies (i.e., emerging or demonstration technologies) are technically feasible and have the potential to make a significant contribution to energy saving and CO2 emissions reduction, but fall short economically to be included. However, they may also have the cost effective potential for significant cost reduction and/or performance improvement in the future under learning effects such as ‘learning-by-doing’. The investigation is carried out using ISEEM, a technology oriented, linear optimization model. We investigated how steel demand is balanced with/without the availability learning curve, compared to a Reference scenario. The retrofit (or investment in some cases) costs of energy efficient technologies decline in the scenario where learning curve is applied. The analysis also addresses market penetration of energy efficient technologies, energy saving, and CO2 emissions in the U.S. iron and steel sector with/without learning impact. Accordingly, the study helps those who use energy models better manage the price barriers preventing unrealistic diffusion of energy-efficiency technologies, better understand the market and learning system involved, predict future achievable learning rates more accurately, and project future savings via energy-efficiency technologies with presence of learning. We conclude from our analysis that, most of the existing energy efficiency technologies that are currently used in the U.S. iron and steel sector are cost effective. Penetration levels increases through the years, even though there is no price reduction. However, demonstration technologies are not economically

  1. Characterisation of NEXT-DEMO using xenon K$_{\\alpha}$ X-rays

    CERN Document Server

    Lorca, D; Laing, A; Ferrario, P; Gómez-Cadenas, J J; Álvarez, V; Borges, F I G; Camargo, M; Cárcel, S; Cebrián, S; Cervera, A; Conde, C A N; Dafni, T; Díaz, J; Esteve, R; Fernandes, L M P; Ferreira, A L; Freitas, E D C; Gehman, V M; Goldschmidt, A; Gómez, H; González-Díaz, D; Gutiérrez, R M; Hauptman, J; Morata, J A Hernando; Herrera, D C; Irastorza, I G; Labarga, L; Liubarsky, I; Losada, M; Luzón, G; Marí, A; Martínez-Lema, G; Martínez, A; Miller, T; Monrabal, F; Monserrate, M; Monteiro, C M B; Mora, F J; Moutinho, L M; Vidal, J Muñoz; Nebot-Guinot, M; Nygren, D; Oliveira, C A B; Pérez, J; Aparicio, J L Pérez; Renner, J; Ripoll, L; Rodríguez, A; Rodríguez, J; Santos, F P; Santos, J M F dos; Seguí, L; Serra, L; Shuman, D; Simón, A; Sofka, C; Sorel, M; Toledo, J F; Torrent, J; Tsamalaidze, Z; Veloso, J F C A; Webb, R; White, J T; Yahlali, N

    2014-01-01

    The NEXT experiment aims to observe the neutrinoless double beta decay of $^{136}$Xe in a high pressure gas TPC using electroluminescence (EL) to amplify the signal from ionization. Understanding the response of the detector is imperative in achieving a consistent and well understood energy measurement. The abundance of xenon k-shell x-ray emission during data taking has been identified as a multitool for the characterisation of the fundamental parameters of the gas as well as the equalisation of the response of the detector. The NEXT-DEMO prototype is a ~1.5 kg volume TPC filled with natural xenon. It employs an array of 19 PMTs as an energy plane and of 256 SiPMs as a tracking plane with the TPC light tube and SiPM surfaces being coated with tetraphenyl butadiene (TPB) which acts as a wavelength shifter for the VUV scintillation light produced by xenon. This paper presents the measurement of the properties of the drift of electrons in the TPC, the effects of the EL production region, and the extraction of p...

  2. Complex X-ray Absorption and the Fe K(alpha) Profile in NGC 3516

    Science.gov (United States)

    Turner, T. J.; Kraemer, S. B.; George, I. M.; Reeves, J. N.; Botorff, M. C.

    2004-01-01

    We present data from simultaneous Chandra, XMM-Newton and BeppoSAX observations of the Seyfert 1 galaxy NGC 3516, taken during 2001 April and November. We have investigated the nature of the very flat observed X-ray spectrum. Chandra grating data show the presence of X-ray absorption lines, revealing two distinct components of the absorbing gas, one which is consistent with our previous model of the UV/X-ray absorber while the other, which is outflowing at a velocity of approximately 1100 kilometers per second, has a larger column density and is much more highly ionized. The broad-band spectral characteristics of the X-ray continuum observed with XMM during 2001 April, reveal the presence of a third layer of absorption consisting of a very large column (approximately 2.5 x 10(exp 23) per square centimeter) of highly ionized gas with a covering fraction approximately 50%. This low covering fraction suggests that the absorber lies within a few 1t-days of the X-ray source and/or is filamentary in structure. Interestingly, these absorbers are not in thermal equilibrium with one another. The two new components are too highly ionized to be radiatively accelerated, which we suggest is evidence for a hydromagnetic origin for the outflow. Applying our model to the November dataset, we can account for the spectral variability primarily by a drop in the ionization states of the absorbers, as expected by the change in the continuum flux. When this complex absorption is accounted for we find the underlying continuum to be typical of Seyfert 1 galaxies. The spectral curvature attributed to the high column absorber, in turn, reduces estimates of the flux and extent of any broad Fe emission line from the accretion disk.

  3. Emission of organic compounds from mould and core binders used for casting iron, aluminium and bronze in sand moulds

    DEFF Research Database (Denmark)

    Tiedje, Niels Skat; Crepaz, Rudolf; Eggert, Torben;

    2010-01-01

    of binders was monitored when cast iron, bronze and aluminium was poured in the moulds. Binder degradation was measured by collecting off gasses in a specially designed ventilation hood at a constant flow rate. Samples were taken from the ventilation system and analysed for hydrocarbons and CO content...... compositions were tested. A test method that provides uniform test conditions is described. The method can be used as general test method to analyse off gasses from binders. Moulds containing a standard size casting were produced and the amount and type of organic compounds resulting from thermal degradation...

  4. A Chandra Observation of the Ultraluminous Infrared Galaxy IRAS 19254-7245 (The Superantennae): X-Ray Emission from the Compton-Thick Active Galactic Nucleus and the Diffuse Starburst

    Science.gov (United States)

    Jia, Jianjun; Ptak, Andrew; Heckman, Timothy M.; Braito, Valentina; Reeves, James

    2012-01-01

    We present a Chandra observation of IRAS 19254-7245, a nearby ultraluminous infrared galaxy also known as the Superantennae. The high spatial resolution of Chandra allows us to disentangle for the first time the diffuse starburst (SB) emission from the embedded Compton-thick active galactic nucleus (AGN) in the southern nucleus. No AGN activity is detected in the northern nucleus. The 2-10 keV spectrum of the AGN emission is fitted by a flat power law (TAU = 1.3) and an He-like Fe Kalpha line with equivalent width 1.5 keV, consistent with previous observations. The Fe K line profile could be resolved as a blend of a neutral 6.4 keV line and an ionized 6.7 keV (He-like) or 6.9 keV (H-like) line. Variability of the neutral line is detected compared with the previous XMM-Newton and Suzaku observations, demonstrating the compact size of the iron line emission. The spectrum of the galaxy-scale extended emission excluding the AGN and other bright point sources is fitted with a thermal component with a best-fit kT of approximately 0.8 keV. The 2-10 keV luminosity of the extended emission is about one order of magnitude lower than that of the AGN. The basic physical and structural properties of the extended emission are fully consistent with a galactic wind being driven by the SB. A candidate ultraluminous X-ray source is detected 8 south of the southern nucleus. The 0.3 - 10 keV luminosity of this off-nuclear point source is approximately 6 x 10(exp 40) erg per second if the emission is isotropic and the source is associated with the Superantennae.

  5. 2020年我国钢铁行业C02排放趋势和减排路径分析%Analysis on CO2 Emission Trend and Emission Reduction Path of China's Steel and Iron Industry in 2020

    Institute of Scientific and Technical Information of China (English)

    袁敏; 康艳兵; 刘强; 赵盟

    2012-01-01

    我国钢铁行业CO2排放占全国排放总量的近20%,分析钢铁行业的CO2排放趋势和减排路径对我国控制温室气体排放有着重要的现实意义.本文从影响钢铁行业排放的主要影响因素着手,分析了钢铁产量和工序能耗的现状及未来发展趋势,测算了2010 -2020年钢铁行业排放趋势和减排潜力,同时给出了减排途径和各种减排措施的贡献度,并提出了相关政策建议.%CO2 emission from China's steel and iron industry accounts for nearly 20% of total national emissions. Analysis on CO2 emission trend and emission reduction path of steel and iron industry is significant to control CO2 emissions in China. From the perspective of major influencing factors, this paper analyzes the status and future trend of steel and iron production and energy consumption per unit of product, calculates historical and future emissions as well as emission reduction potentials, and also analyzes reduction paths and contributions of various reduction measures, finally proposes appropriate policy recommendations.

  6. Investigation of iron emission lines in the eclipsing high mass X-ray binary pulsar OAO 1657-415

    CERN Document Server

    Jaisawal, Gaurava K

    2016-01-01

    We present the results obtained from timing and spectral studies of high mass X-ray binary pulsar OAO 1657-415 using a Suzaku observations in 2011 September. X-ray pulsations were detected in the light curves up to $\\sim$70 keV. The continuum spectra during the high- and low-flux regions in light curves were well described by high energy cutoff power-law model along with a blackbody component and iron fluorescent lines at 6.4 keV and 7.06 keV. Time resolved spectroscopy was carried out by dividing the entire observations into 18 narrow segments. Presence of additional dense matter at various orbital phases was confirmed as the cause of low-flux regions in the observations. Presence of additional matter at several orbital phases of the pulsar was interpreted as due to the inhomogeneously distributed clumps of matter around the neutron star. Using clumpy wind hypothesis, the physical parameters of the clumps causing the high- and low-flux episodes in the pulsar light curve were estimated. The equivalent width o...

  7. [Effect of Ferric Iron on Nitrogen Immigration and Transformation and Nitrous Oxide Emission During Simultaneous Nitrification Denitrification Process].

    Science.gov (United States)

    Li, Hao; Yan, Yu-jie; Xie, Hui-jun; Jia, Wen-lin; Hu, Zhen; Zhang, Jian

    2015-04-01

    Effect of Fe(III) concentration on nitrogen immigration and transformation and nitrous oxide emission during the simultaneous nitrification denitrification (SND) process was investigated. Higher nitrogen removal efficiency was obtained when the Fe(III) concentration was 20 mg x L(-1), while lower nitrogen removal efficiency was observed when the Fe (III) concentration turned to 60 mg x L(-1). In addition, higher Fe(III) concentration significantly enhanced the N2O emission, as well as the N2O conversion ratio. This was mainly attributed to (1) the high concentration of nitrite accumulation during the oxic stage, which was caused by lower dehydrogenase activity at high Fe(III) concentration; (2) less PHB production during the anoxic stage, which would led to shortage of carbon source for denitrification in the following oxic stage. The results also showed that Fe(III) addition could improve the TP removal efficiency. TP removal efficiency increased with increasing Fe(III) concentration, mainly because of extra chemical reaction.

  8. Scale heights and equivalent widths of the iron K-shell lines in the Galactic diffuse X-ray emission

    CERN Document Server

    Yamauchi, Shigeo; Nobukawa, Masayoshi; Uchiyama, Hideki; Koyama, Katsuji

    2016-01-01

    This paper reports the analysis of the X-ray spectra of the Galactic diffuse X-ray emission (GDXE) in the Suzaku archive. The fluxes of the Fe I K alpha (6.4 keV), Fe XXV,He alpha (6.7 keV) and Fe XXVI Ly alpha (6.97 keV) lines are separately determined. From the latitude distributions, we confirm that the GDXE is decomposed into the Galactic center (GCXE), the Galactic bulge (GBXE) and the Galactic ridge (GRXE) X-ray emissions. The scale heights (SHs) of the Fe XXV He alpha line of the GCXE, GBXE and GRXE are determined to be ~40, ~310 and ~140 pc, while those of the Fe I K alpha line are ~30, ~160 and ~70 pc, respectively. The mean equivalent widths (EWs) of the sum of the Fe XXV He alpha and Fe XXVI Ly alpha lines are ~750 eV, ~600 eV and ~550 eV, while those of the Fe I K alpha line are ~150~eV, ~60~eV and ~100~eV for the GCXE, GBXE and GRXE, respectively. The origin of the GBXE, GRXE and GCXE is separately discussed based on the new results of the SHs and EWs, in comparison with those of the Cataclysmic ...

  9. Analysis of Electrodeposited Nickel-Iron Alloy Film Composition Using Particle-Induced X-Ray Emission

    Directory of Open Access Journals (Sweden)

    Alyssa A. Frey

    2011-01-01

    Full Text Available The elemental composition of electrodeposited NiFe thin films was analyzed with particle-induced X-ray emission (PIXE. The thin films were electrodeposited on polycrystalline Au substrates from a 100 mM NiSO4, 10 mM FeSO4, 0.5 M H3BO3, and 1 M Na2SO4 solution. PIXE spectra of these films were analyzed to obtain relative amounts of Ni and Fe as a function of deposition potential and deposition time. The results show that PIXE can measure the total deposited metal in a sample over at least four orders of magnitude with similar fractional uncertainties. The technique is also sensitive enough to observe the variations in alloy composition due to sample nonuniformity or variations in deposition parameters.

  10. Method development for the determination of calcium, copper, magnesium, manganese, iron, potassium, phosphorus and zinc in different types of breads by microwave induced plasma-atomic emission spectrometry.

    Science.gov (United States)

    Ozbek, Nil; Akman, Suleyman

    2016-06-01

    A novel method was developed for the determination of calcium, magnesium, potassium, iron, copper, zinc, and manganese and phosphorous in various kinds of breads samples sold in Turkey by microwave plasma-atomic emission spectrometry (MIP-AES). Breads were dried at 100 °C for one day, ground thoroughly and then digested using nitric acid/hydrogen per oxide (3:1). The analytes in certified reference wheat flour and maize flour samples were determined in the uncertainty limits of the certified values as well as the analytes added to the mixture of ground bread and acid mixture prior to digestion were recovered quantitatively (>90%). Therefore, all determinations were made by linear calibration technique using aqueous standards. The LOD values for Ca, Cu, Fe, K, Mg, Mn, P and Zn were 13.1, 0.28, 4.47, 118, 1.10, 0.41, 7550 and 3.00 ng mL(-1), respectively. No spectral interference was detected at the working wavelengths of the analytes.

  11. Emission Control on № 5 & 6 Coke Oven Batteries of Handan Iron & Steel Complex%邯钢5、6号焦炉的烟尘治理

    Institute of Scientific and Technical Information of China (English)

    胡汉; 许波; 吴云强

    2001-01-01

    The process of emission control on № 5 & 6 coke oven batteries of Handan Iron & Steel Complex is introduced, and the control mode, software feature, problems occurred in production and improving method for automatic control system of coke oven emission control are described.%介绍了邯钢5、6号焦炉烟尘的治理工艺及其自动控制系统的控制方式、软件特点、生产中出现的问题及改进方法。

  12. Emission of BTEX and PAHs from molding sands with furan cold setting resins containing different contents of free furfuryl alcohol during production of cast iron

    Directory of Open Access Journals (Sweden)

    Mariusz Holtzer

    2015-11-01

    Full Text Available At present, furan resin is the largest selling no-bake system of moulding sands. The most commonly used furan no-bake binders (FNB are condensation products of furfuryl alcohol (FA urea, formaldehyde and phenol. They are generally cured by exposure to organic sulfonic acids. FNB provide excellent mold and core strength, cure rapidly and allow the sand to be reclaimed at fairly high yields, generally 75%-80%, especially in applications where due allowance is made for the need to keep total sulfur content below 0.1%. However, due to probable carcinogenic properties of furfuryl alcohol, the EU Directive limits the content of this substance (in a monomer form in resin to 25%. The classification of furfuryl alcohol and the resulting furan resin products has changed from "harmful" to "toxic" by inhalation? The aim of this study was to determine the effect of free furfuryl alcohol content in the resin on the emission of harmful substances from the BTEX (Benzene Toluene Ethylbenzene & Xylene and PAHs (polycyclic aromatic hydrocarbon group exposed to high temperature and how it affects the emissions allowance of reclaimed sand in the matrix. Three resins from a leading manufacturer were examined, which contain a free furfuryl alcohol content of 71%-72%, about 50% and < 25%, respectively. The hardener for each resin was 65% aqueous solution of paratoluenesulfonic acid. Tests were carried out in semi-industrial conditions where liquid cast-iron was poured into sample sand mold at 1,350 ìC. The matrix of the studied sands was reclaimed in the amount of 0, 50%, 100%, respectively. With the increase of free furfuryl alcohol content, the volume of evolved gases decreased. For all resins the main component from the BTEX group dominating in the emitted gases was benzene; however toluene also appeared in the amount of a few percentages. In contrast, ethylbenzene and xylenes occurred only in the gases emitted from resin-bonded sands with the largest furfuryl

  13. Pressure effect on the electronic structure of iron in (Mg,Fe)(Al,Si)O3 perovskite: A combined synchrotron M?ssbauer and x-ray emission spectroscopy study up to 100 GPa

    Energy Technology Data Exchange (ETDEWEB)

    Li, J; Sturhahn, W; Jackson, J; Struzhkin, V V; Lin, J F; Zhao, J; Mao, H K; Shen, G

    2006-01-23

    We investigated the valence and spin state of iron in an Al-bearing ferromagnesian silicate perovskite sample, (Mg{sub 0.88}Fe{sub 0.09})(Si{sub 0.94}Al{sub 0.10})O{sub 3}, at 300 K and up to 100 GPa, using diamond-anvil cells and synchrotron Moessbauer spectroscopy techniques. Under elevated pressures, our Moessbauer time spectra are sufficiently fitted by a ''three-doublet'' model, which assumes two ferrous (Fe{sup 2+}) iron types and one ferric (Fe{sup 3+}) iron type with distinct hyperfine parameters. At pressures above 20 GPa, the fraction of the ferric iron, Fe{sup 3+}/{Sigma}Fe, is about 75% and remains unchanged to the highest pressure, indicating a fixed valence state of iron within this pressure range. Between 20 and 100 GPa, the quadruple splittings of all three iron types do not change with pressure, while the isomer shift between the Fe{sup 3+} types and the Fe{sup 2+} type increases continuously with increasing pressure. In conjunction with previous x-ray emission data on the same sample, the unchanging quadruple splittings and increasing isomer shift suggest that Fe{sup 2+} undergoes a broad spin crossover towards the low-spin state at 100 GPa, while Fe{sup 3+} remains in the high-spin state. The essentially constant quadruple splittings of Fe{sup 2+} can also be taken as an indication for strong resistance against further distortion of the local iron environment after initial compression.

  14. 铁矿石烧结行业二英类形成机制与排放水平%Formation mechanism and emission profiles of PCDD/Fs in iron ore sintering

    Institute of Scientific and Technical Information of China (English)

    王梦京; 吴素愫; 高新华; 侯梅芳; 唐琛; 刘文彬

    2014-01-01

    Iron ore sintering is one of the important emission sources for PCDD/Fs. This paper summarized formation mechanisms of PCDD/Fs in sintering process and the emission profile of PCDD/Fs in typical sintering stack gas. Key influencing factors of PCDD/Fs formation, including temperature, time, oxygen concentration and other conditions in raw material composition were analyzed. Reduction technologies of PCDD/Fs emission were also suggested in this paper. Finally, it provided analysis and outlook on the current emission of PCDD/Fs from iron ore sintering industry in China and several developed countries. It is aimed to provide reference for the management and reduction of emission of PCDD/Fs in the iron ore sintering industry in China.%铁矿石烧结是我国重要的二英类( PCDD/Fs)排放源之一。本文总结了烧结过程PCDD/Fs的生成机制,以及典型烧结烟气的PCDD/Fs排放特征。针对影响PCDD/Fs生成的关键因素进行了分析,探讨了原料组成中关键元素的影响,以及温度、时间和氧气含量等条件的影响,进而对PCDD/Fs的减排技术等方面进行了讨论。最后本文还对部分发达国家和我国的铁矿石烧结行业PCDD/Fs排放现状进行了分析和展望。可为我国铁矿石烧结行业PCDD/Fs的管理和减排提供参考。

  15. Accretion Disk Line Emission in AGN a Devil's Advocacy

    CERN Document Server

    Sulentic, J W; Dultzin-Hacyan, D

    1998-01-01

    We review the evidence for AGN optical and X-ray broad line emission from an accretion disk. We argue that there is little, if any, statistical evidence to support this assertion. The inconsistency is strongest for the rare class of Balmer profiles that show double peaks. The line profiles predicted by a simple illuminated disk model are often incompatible with the observations. We suggest that the Fe Kalpha line in Seyfert 1 galaxies, where a broad line is most often and most strongly detected, is actually a composite of two lines both with Gaussian profiles; one narrow/unshifted and the other broad/redshifted.

  16. Iron Test

    Science.gov (United States)

    ... as: Serum Iron; Serum Fe Formal name: Iron, serum Related tests: Ferritin ; TIBC, UIBC and Transferrin ; Hemoglobin ; Hematocrit ; Complete Blood Count ; Reticulocyte Count ; Zinc Protoporphyrin ; Iron Tests ; Soluble Transferrin Receptor ... I should know? How is it used? Serum iron, total iron-binding capacity (TIBC) , and/or ...

  17. Selective Iron(III ion uptake using CuO-TiO2 nanostructure by inductively coupled plasma-optical emission spectrometry

    Directory of Open Access Journals (Sweden)

    Rahman Mohammed M

    2012-12-01

    Full Text Available Abstract Background CuO-TiO2 nanosheets (NSs, a kind of nanomaterials is one of the most attracting class of transition doped semiconductor materials due to its interesting and important optical, electrical, and structural properties and has many technical applications, such as in metal ions detection, photocatalysis, Chemi-sensors, bio-sensors, solar cells and so on. In this paper the synthesis of CuO-TiO2 nanosheets by the wet-chemically technique is reported. Methods CuO-TiO2 NSs were prepared by a wet-chemical process using reducing agents in alkaline medium and characterized by UV/vis., FT-IR spectroscopy, X-ray photoelectron spectroscopy (XPS, powder X-ray diffraction (XRD, and field-emission scanning electron microscopy (FE-SEM etc. Results The structural and optical evaluation of synthesized NSs were measured by XRD pattern, Fourier transform infrared (FT-IR and UV–vis spectroscopy, respectively which confirmed that the obtained NSs are well-crystalline CuO-TiO2 and possessing good optical properties. The morphological analysis of CuO-TiO2 NSs was executed by FE-SEM, which confirmed that the doped products were sheet-shaped and growth in large quantity. Here, the analytical efficiency of the NSs was applied for a selective adsorption of iron(III ion prior to detection by inductively coupled plasma-optical emission spectrometry (ICP-OES. The selectivity of NSs towards various metal ions, including Au(III, Cd(II, Co(II, Cr(III, Fe(III, Pd(II, and Zn(II was analyzed. Conclusions Based on the selectivity study, it was confirmed that the selectivity of doped NSs phase was the most towards Fe(III ion. The static adsorption capacity for Fe(III was calculated to be 110.06 mgg−1. Results from adsorption isotherm also verified that the adsorption process was mainly monolayer-adsorption onto a surface containing a finite number of CuO-TiO2 NSs adsorption sites.

  18. Determining optimal operation parameters for reducing PCDD/F emissions (I-TEQ values) from the iron ore sintering process by using the Taguchi experimental design.

    Science.gov (United States)

    Chen, Yu-Cheng; Tsai, Perng-Jy; Mou, Jin-Luh

    2008-07-15

    This study is the first one using the Taguchi experimental design to identify the optimal operating condition for reducing polychlorinated dibenzo-p-dioxins and dibenzofurans (PCDD/ Fs) formations during the iron ore sintering process. Four operating parameters, including the water content (Wc; range = 6.0-7.0 wt %), suction pressure (Ps; range = 1000-1400 mmH2O), bed height (Hb; range = 500-600 mm), and type of hearth layer (including sinter, hematite, and limonite), were selected for conducting experiments in a pilot scale sinter pot to simulate various sintering operating conditions of a real-scale sinter plant We found that the resultant optimal combination (Wc = 6.5 wt%, Hb = 500 mm, Ps = 1000 mmH2O, and hearth layer = hematite) could decrease the emission factor of total PCDD/Fs (total EF(PCDD/Fs)) up to 62.8% by reference to the current operating condition of the real-scale sinter plant (Wc = 6.5 wt %, Hb = 550 mm, Ps = 1200 mmH2O, and hearth layer = sinter). Through the ANOVA analysis, we found that Wc was the most significant parameter in determining total EF(PCDD/Fs (accounting for 74.7% of the total contribution of the four selected parameters). The resultant optimal combination could also enhance slightly in both sinter productivity and sinter strength (30.3 t/m2/day and 72.4%, respectively) by reference to those obtained from the reference operating condition (29.9 t/m (2)/day and 72.2%, respectively). The above results further ensure the applicability of the obtained optimal combination for the real-scale sinter production without interfering its sinter productivity and sinter strength.

  19. Broad-band X-ray emission and the reality of the broad iron line from the neutron star-white dwarf X-ray binary 4U 1820-30

    Science.gov (United States)

    Mondal, Aditya S.; Dewangan, G. C.; Pahari, M.; Misra, R.; Kembhavi, A. K.; Raychaudhuri, B.

    2016-09-01

    Broad relativistic iron lines from neutron star X-ray binaries are important probes of the inner accretion disc. The X-ray reflection features can be weakened due to strong magnetic fields or very low iron abundances such as is possible in X-ray binaries with low mass, first generation stars as companions. Here, we investigate the reality of the broad iron line detected earlier from the neutron-star low-mass X-ray binary 4U 1820-30 with a degenerate helium dwarf companion. We perform a comprehensive, systematic broad-band spectral study of the atoll source using Suzaku and simultaneous NuSTAR and Swift observations. We have used different continuum models involving accretion disc emission, thermal blackbody and thermal Comptonization of either disc or blackbody photons. The Suzaku data show positive and negative residuals in the region of Fe K band. These features are well described by two absorption edges at 7.67 ± 0.14 keV and 6.93 ± 0.07 keV or partial covering photoionized absorption or by blurred reflection. Though, the simultaneous Swift and NuSTAR data do not clearly reveal the emission or absorption features, the data are consistent with the presence of either absorption or emission features. Thus, the absorption based models provide an alternative to the broad iron line or reflection model. The absorption features may arise in winds from the inner accretion disc. The broad-band spectra appear to disfavour continuum models in which the blackbody emission from the neutron-star surface provides the seed photons for thermal Comptonization. Our results suggest emission from a thin accretion disc (kTdisc ˜ 1 keV), Comptonization of disc photons in a boundary layer most likely covering a large fraction of the neutron-star surface and innermost parts of the accretion disc, and blackbody emission (kTbb ˜ 2 keV) from the polar regions.

  20. Atmospheric iron deposition: global distribution, variability, and human perturbations.

    Science.gov (United States)

    Mahowald, Natalie M; Engelstaedter, Sebastian; Luo, Chao; Sealy, Andrea; Artaxo, Paulo; Benitez-Nelson, Claudia; Bonnet, Sophie; Chen, Ying; Chuang, Patrick Y; Cohen, David D; Dulac, Francois; Herut, Barak; Johansen, Anne M; Kubilay, Nilgun; Losno, Remi; Maenhaut, Willy; Paytan, Adina; Prospero, Joseph M; Shank, Lindsey M; Siefert, Ronald L

    2009-01-01

    Atmospheric inputs of iron to the open ocean are hypothesized to modulate ocean biogeochemistry. This review presents an integration of available observations of atmospheric iron and iron deposition, and also covers bioavailable iron distributions. Methods for estimating temporal variability in ocean deposition over the recent past are reviewed. Desert dust iron is estimated to represent 95% of the global atmospheric iron cycle, and combustion sources of iron are responsible for the remaining 5%. Humans may be significantly perturbing desert dust (up to 50%). The sources of bioavailable iron are less well understood than those of iron, partly because we do not know what speciation of the iron is bioavailable. Bioavailable iron can derive from atmospheric processing of relatively insoluble desert dust iron or from direct emissions of soluble iron from combustion sources. These results imply that humans could be substantially impacting iron and bioavailable iron deposition to ocean regions, but there are large uncertainties in our understanding.

  1. Broadband X-ray emission and the reality of the broad iron line from the Neutron Star - White Dwarf X-ray binary 4U 1820-30

    CERN Document Server

    Mondal, Aditya S; Pahari, Mayukh; Misra, Ranjeev; Kembhavi, Ajit K; Raychaudhuri, Biplab

    2016-01-01

    Broad relativistic iron lines from neutron star X-ray binaries are important probes of the inner accretion disk. The X-ray reflection features can be weakened due to strong magnetic fields or very low iron abundances such as is possible in X-ray binaries with low mass, first generation stars as companions. Here we investigate the reality of the broad iron line detected earlier from the neutron star low mass X-ray binary 4U~1820--30 with a degenerate helium dwarf companion. We perform a comprehensive, systematic broadband spectral study of the atoll source using \\suzaku{} and simultaneous \

  2. Energy Consumption and Smoke and Dust Emissions Analysis of Typical Iron and Steel Production Enterprise%典型钢铁企业物能消耗与烟粉尘排放分析

    Institute of Scientific and Technical Information of China (English)

    李小玲; 孙文强; 赵亮; 蔡九菊

    2016-01-01

    Taking a typical iron and steel production enterprise as the research object,based on the practical production data of enterprise,substance metabolism model was constructed by using material flow analysis method (MFA).According to energy use,resource use and pollutant emissions indexes,resources and energy consumption and smoke and dust emissions situation of the iron and steel production enterprises were quantitatively described.The results showed that for enterprises,the total resource consumption per ton of steel of the blast furnace converter’s long process is 208.6 t.Fuel consumption is 93.9% of the total energy consumption.The smoke and dust emission per ton of steel is 648.08 g,of which sintering and iron-making process make the biggest contribution and account for 45 percent and 36 percent,respectively.The total resource consumption of electric furnace’s short process is 1.31 t,of which electrical energy consumption is 96.7% of the total energy consumption and the smoke and dust emissions per ton of steel is 67 g.As for processes,the emissions of sintering,coking and iron-making process are 222.50 g /t sinter,1 18.20 g /t coke and 245.27 g /t iron.Accordingly the directional advices on energy-saving and emission reduction in enterprises and the adjustment of industrial structure are put forward to reduce the pressure on the environment and realize the sustainable development of iron and steel enterprises.%以典型钢铁生产企业为研究对象,基于企业实际生产数据,采用物质流分析法(MFA),构建物质代谢模型.建立了能源、资源利用和污染物排放分析指标,定量描述了钢铁企业的资源能源消耗及烟粉尘排放情况.结果表明:企业层面,高炉-转炉长流程吨钢总资源消耗量为208.6 t,燃料能消耗量占能源消耗总量的93.9%,吨钢烟粉尘排放量为648.08 g,烧结和炼铁工序贡献最大,分别占总排放量的45%和36%.电炉短流程总资源消耗量为1.31 t,电能

  3. Combustion iron distribution and deposition

    Science.gov (United States)

    Luo, Chao; Mahowald, N.; Bond, T.; Chuang, P. Y.; Artaxo, P.; Siefert, R.; Chen, Y.; Schauer, J.

    2008-03-01

    Iron is hypothesized to be an important micronutrient for ocean biota, thus modulating carbon dioxide uptake by the ocean biological pump. Studies have assumed that atmospheric deposition of iron to the open ocean is predominantly from mineral aerosols. For the first time we model the source, transport, and deposition of iron from combustion sources. Iron is produced in small quantities during fossil fuel burning, incinerator use, and biomass burning. The sources of combustion iron are concentrated in the industrialized regions and biomass burning regions, largely in the tropics. Model results suggest that combustion iron can represent up to 50% of the total iron deposited, but over open ocean regions it is usually less than 5% of the total iron, with the highest values (ocean biogeochemistry the bioavailability of the iron is important, and this is often estimated by the fraction which is soluble (Fe(II)). Previous studies have argued that atmospheric processing of the relatively insoluble Fe(III) occurs to make it more soluble (Fe(II)). Modeled estimates of soluble iron amounts based solely on atmospheric processing as simulated here cannot match the variability in daily averaged in situ concentration measurements in Korea, which is located close to both combustion and dust sources. The best match to the observations is that there are substantial direct emissions of soluble iron from combustion processes. If we assume observed soluble Fe/black carbon ratios in Korea are representative of the whole globe, we obtain the result that deposition of soluble iron from combustion contributes 20-100% of the soluble iron deposition over many ocean regions. This implies that more work should be done refining the emissions and deposition of combustion sources of soluble iron globally.

  4. Bremsstrahlung and K(alpha) fluorescence measurements for inferring conversion efficiencies into fast ignition relevant hot electrons

    Energy Technology Data Exchange (ETDEWEB)

    Chen, C D; Patel, P K; Hey, D S; Mackinnon, A J; Key, M H; Akli, K U; Bartal, T; Beg, F N; Chawla, S; Chen, H; Freeman, R R; Higginson, D P; Link, A; Ma, T Y; MacPhee, A G; Stephens, R B; Van Woerkom, L D; Westover, B; Porkolab, M

    2009-07-24

    The Bremsstrahlung and K-shell emission from 1 mm x 1 mm x 1 mm planar targets irradiated by a short-pulse 3 x 10{sup 18}-8 x 10{sup 19} W/cm{sup 2} laser were measured. The Bremsstrahlung was measured using a filter stack spectrometer with spectral discrimination up to 500 keV. K-shell emission was measured using a single photon counting charge coupled device (CCD). From Monte Carlo modeling of the target emission, conversion efficiencies into 1-3 MeV electrons of 3-12%, representing 20-40% total conversion efficiencies were inferred for intensities up to 8 x 10{sup 19} W/cm{sup 2}. Comparisons to scaling laws using synthetic energy spectra generated from the intensity distribution of the focal spot imply slope temperatures less than the ponderomotive potential of the laser. Resistive transport effects may result in potentials of a few hundred kV in the first few tens of microns in the target. This would lead to higher total conversion efficiencies than inferred from Monte Carlo modeling but lower conversion efficiencies into 1-3 MeV electrons.

  5. Značaj emisije polikloriranih dibenzo-p-dioksina i dibenzofurana iz procesa proizvodnje željeza i čelika (Importance of Polychlorinated Dibenzo-p-dioxins and Dibenzofurans Emissions from Iron and Steel Production Processes

    Directory of Open Access Journals (Sweden)

    Šmit, Z.

    2006-12-01

    Full Text Available Metals and metallic products are fundamental to a large number of modern industries and steel is certainly one of the most significant metallurgical products. Steel and steel castings as universal production material, that provided the grounds for the contemporary industrialization process,will have a continuously irreplaceable role in the future, regardless of the fact that nowadays steel materials are often replaced by other materials (ceramics, polymers, etc., whenever it is technically required and cost-justified.The development of metallurgy and metallurgical processes is accompanied by pollution of the environment that directly or indirectly endangered the health of humans, certain animal and plant species, water resources systems, and soil. It also lead to increased erosion of material goodsand caused many other adverse social and economy-related effects.The integral steelworks concept has, for example, set off a significant increase in the number of emission sources and the increase of harmful substances concentration in the environment. The largest polluters have always been coking plants, iron ore agglomeration facilities, blast furnaces, steel mills, foundries and thermal energy plants.Numerous fundamental scientific research works have proven a series of adverse effects caused by uncontrolled emissions of harmful substances from these plants. Beside the considerable quantities of usual and well-known polluting substances such as sulfur and carbon oxides, fluorides,ammonia, benzene, heavy metals, phenols, cyanides, oil and grease, slag, used refractory material, metallic scrapings, sludge, dust, and scale, there are also relatively small pollutions with long-lasting effects that are hazardous even in their low concentrations and they rarely receivedue attention.This polluting substance group consists of persistent organic pollutions represented by polycyclic aromatic hydrocarbon (PAH, polychlorinated biphenyls (PCBs, polychlorinated

  6. Comment on "The dust sublimation radius as an outer envelope to the bulk of the narrow Fe K$\\alpha$ line emission in Type 1 AGN"

    CERN Document Server

    Minezaki, Takeo

    2015-01-01

    Recently, Gandhi, H\\"onig, and Kishimoto submitted a manuscript to the arXiv e-print service on the location of the emitting region of the narrow FeK$\\alpha $ line that appears in the X-ray spectra of active galactic nuclei (AGNs) compared with the inner radius of the dust torus (arXiv:1502.02661). Prior to their manuscript, a similar discussion had already been presented in a section of Minezaki & Matsushita (2015), which had been accepted for publication in the Astrophysical Journal. Because Gandhi et al. made no reference to Minezaki & Matsushita (2015) apart from improperly citing it merely as an application of the dust reverberation of AGNs, we present a brief comparison of both papers. Gandhi et al. compared the location of the FeK$\\alpha$ emitting region with the individually measured radius of the dust torus for type 1 AGNs, whereas Minezaki & Matsushita (2015) examined it based on the scaling relation of the dust reverberation radius for both type 1 and type 2 AGNs. Nevertheless, Gandhi e...

  7. The ASCA X-Ray Spectrum Of The Broad-Line Radio Galaxy Pictor A A Simple Power Law With No Fe K-$\\alpha$ Line

    CERN Document Server

    Eracleous, M; Eracleous, Michael; Halpern, Jules P.

    1998-01-01

    We present the X-ray spectrum of the broad-line radio galaxy Pictor A as observed by ASCA in 1996. The main objective of the observation was to detect and study the profiles of the Fe~K$\\alpha$ lines. The motivation was the fact that the Balmer lines of this object show well-separated displaced peaks, suggesting an origin in an accretion disk. The 0.5-10 keV X-ray spectrum is described very well by a model consisting of a power law of photon index 1.77 modified by interstellar photoelectric absorption. We find evidence for neither a soft nor a hard (Compton reflection) excess. More importantly, we do not detect an Fe K-alpha line, in marked contrast with the spectra of typical Seyfert galaxies and other broad-line radio galaxies observed by ASCA. The 99%-confidence upper limit on the equivalent width of an unresolved line at a rest energy of 6.4 keV is 100 eV, while for a broad line (FWHM of approximately 60,000 km/s) the corresponding upper limit is 135 eV. We discuss several possible explanations for the we...

  8. Iron deficiency.

    Science.gov (United States)

    Scrimshaw, N S

    1991-10-01

    The world's leading nutritional problem is iron deficiency. 66% of children and women aged 15-44 years in developing countries have it. Further, 10-20% of women of childbearing age in developed countries are anemic. Iron deficiency is identified with often irreversible impairment of a child's learning ability. It is also associated with low capacity for adults to work which reduces productivity. In addition, it impairs the immune system which reduces the body's ability to fight infection. Iron deficiency also lowers the metabolic rate and the body temperature when exposed to cold. Hemoglobin contains nearly 73% of the body's iron. This iron is always being recycled as more red blood cells are made. The rest of the needed iron does important tasks for the body, such as binds to molecules that are reservoirs of oxygen for muscle cells. This iron comes from our diet, especially meat. Even though some plants, such as spinach, are high in iron, the body can only absorb 1.4-7% of the iron in plants whereas it can absorb 20% of the iron in red meat. In many developing countries, the common vegetarian diets contribute to high rates of iron deficiency. Parasitic diseases and abnormal uterine bleeding also promote iron deficiency. Iron therapy in anemic children can often, but not always, improve behavior and cognitive performance. Iron deficiency during pregnancy often contributes to maternal and perinatal mortality. Yet treatment, if given to a child in time, can lead to normal growth and hinder infections. However, excess iron can be damaging. Too much supplemental iron in a malnourished child promotes fatal infections since the excess iron is available for the pathogens use. Many countries do not have an effective system for diagnosing, treating, and preventing iron deficiency. Therefore a concerted international effort is needed to eliminate iron deficiency in the world.

  9. Analysis of the specific consumption of energy and of carbon specific emissions of the mexican Iron and steel industry; Analisis del consumo especifico de energia y de las emisiones especificas de carbono de la industria siderurgica mexicana

    Energy Technology Data Exchange (ETDEWEB)

    Ozawa, L; Sheinbaum, C. [Instituto de Ingenieria de la UNAM, Mexico, D. F. (Mexico)

    1999-07-01

    From 1970 to 1995, the specific consumption of energy of the Mexican iron and steel industry diminished in 16.2%, and the specific carbon emissions in 21.8%. In order to analyze the factors that favored these diminutions, the specific energy consumption in structural changes and improvements in energy efficiency were segregated; whereas the specific carbon emissions were segregated in structural changes, improvements of energy efficiency, changes in the factors of carbon emissions and in the fuel mixture in the iron and steel industry as well as in the electricity generation. It was observed that the diminution in the specific consumption as well as in the specific carbon emissions were mainly due to technological improvements in the manufacture of the steel: the complete substitution of the open hearth furnaces and a comprehensive penetration of the continuous casting. In spite of these improvements in energy efficiency and to the gradual substitution of coke by natural gas when increasing the production of iron by direct reduction. Though, the emission factor of the electricity was increased due to a greater participation of the fossil plants in 1995 in comparison with 1970. The indicators of energy efficiency of this industry with other countries were compared taking into account their own structure. Finally recommendations are made of measures for energy saving. [Spanish] De 1970 a 1995, el consumo especifico de energia de la industria siderurgica mexicana disminuyo en un 16.2%, y las emisiones especificas de carbono en un 21.8%. Para analizar los factores que favorecieron dichas disminuciones, se desagrego el consumo especifico de energia en cambios estructurales y en mejoras de eficiencia energetica; mientras que las emisiones especificas de carbono se desagregaron en cambios estructurales, mejoras de eficiencia energetica, cambios en los factores de emision de carbono y en la mezcla de combustibles tanto de la industria siderurgica como en la generacion de

  10. Suzaku Observations of Iron K-lines from the Intracluster Medium of the Coma Cluster

    CERN Document Server

    Sato, Takuya; Ota, Naomi; Sato, Kosuke; Nakazawa, Kazuhiro; Sarazin, Craig L

    2011-01-01

    The Coma cluster was observed with an X-ray Imaging Spectrometer (XIS) onboard Suzaku in six pointings, including the central X-ray peak region, the 14'west offset region, 30'and 34'north-west offset regions, and 44'and 60'south-west offset regions. Owing to its lower background level, Suzaku has better sensitivity to Fe K-alpha lines than other satellites. Using precise Fe line measurements, we studied the temperature structure, possible bulk motions, and iron abundance distributions in the intracluster medium (ICM). The observed spectra were well-represented by a single-temperature model, and two- or three- temperature model did not improve chi-square substantially. The temperature, derived from K-alpha line ratios of H-like and He-like Fe, agree with those derived from the single-temperature model. Because the line ratio is a steep function of temperature, the consistency supports the accuracy of temperature measurements conducted with Suzaku. Within the 34'region, the redshift derived from the central ene...

  11. Native iron

    DEFF Research Database (Denmark)

    Brooks, Charles Kent

    2015-01-01

    , a situation unique in the Solar System. In such a world, iron metal is unstable and, as we all know, oxidizes to the ferric iron compounds we call 'rust'. If we require iron metal it must be produced at high temperatures by reacting iron ore, usually a mixture of ferrous (Fe2+) and ferric (Fe3+) oxides (Fe2O3......, hematite, or FeO.Fe2O3, magnetite), with carbon in the form of coke. This is carried out in a blast furnace. Although the Earth's core consists of metallic iron, which may also be present in parts of the mantle, this is inaccessible to us, so we must make our own. In West Greenland, however, some almost...... unique examples of iron metal, otherwise called 'native iron' or 'telluric iron', occur naturally....

  12. Amendments to the Discussion on the Paper Entitled "Normal Spectral Emissivity Measurement of Liquid Iron and Nickel Using Electromagnetic Levitation in Direct Current Magnetic Field"

    Science.gov (United States)

    Kobatake, Hidekazu; Fukuyama, Hiroyuki

    2016-07-01

    We recalculated the normal spectral emissivity of liquid Fe and Ni using the correct electrical and thermophysical parameters based on the Drude model. The newly calculated emissivity values of liquid Fe and Ni were lower by 15 to 20 pct when compared with the experimentally determined values within the wavelength range of 780 to 920 nm.

  13. Iron Homeostasis and Nutritional Iron Deficiency123

    OpenAIRE

    2011-01-01

    Nonheme food ferritin (FTN) iron minerals, nonheme iron complexes, and heme iron contribute to the balance between food iron absorption and body iron homeostasis. Iron absorption depends on membrane transporter proteins DMT1, PCP/HCP1, ferroportin (FPN), TRF2, and matriptase 2. Mutations in DMT1 and matriptase-2 cause iron deficiency; mutations in FPN, HFE, and TRF2 cause iron excess. Intracellular iron homeostasis depends on coordinated regulation of iron trafficking and storage proteins enc...

  14. Intraoperative detection of ¹⁸F-FDG-avid tissue sites using the increased probe counting efficiency of the K-alpha probe design and variance-based statistical analysis with the three-sigma criteria.

    Science.gov (United States)

    Povoski, Stephen P; Chapman, Gregg J; Murrey, Douglas A; Lee, Robert; Martin, Edward W; Hall, Nathan C

    2013-03-04

    Intraoperative detection of (18)F-FDG-avid tissue sites during 18F-FDG-directed surgery can be very challenging when utilizing gamma detection probes that rely on a fixed target-to-background (T/B) ratio (ratiometric threshold) for determination of probe positivity. The purpose of our study was to evaluate the counting efficiency and the success rate of in situ intraoperative detection of (18)F-FDG-avid tissue sites (using the three-sigma statistical threshold criteria method and the ratiometric threshold criteria method) for three different gamma detection probe systems. Of 58 patients undergoing (18)F-FDG-directed surgery for known or suspected malignancy using gamma detection probes, we identified nine (18)F-FDG-avid tissue sites (from amongst seven patients) that were seen on same-day preoperative diagnostic PET/CT imaging, and for which each (18)F-FDG-avid tissue site underwent attempted in situ intraoperative detection concurrently using three gamma detection probe systems (K-alpha probe, and two commercially-available PET-probe systems), and then were subsequently surgical excised. The mean relative probe counting efficiency ratio was 6.9 (± 4.4, range 2.2-15.4) for the K-alpha probe, as compared to 1.5 (± 0.3, range 1.0-2.1) and 1.0 (± 0, range 1.0-1.0), respectively, for two commercially-available PET-probe systems (P < 0.001). Successful in situ intraoperative detection of 18F-FDG-avid tissue sites was more frequently accomplished with each of the three gamma detection probes tested by using the three-sigma statistical threshold criteria method than by using the ratiometric threshold criteria method, specifically with the three-sigma statistical threshold criteria method being significantly better than the ratiometric threshold criteria method for determining probe positivity for the K-alpha probe (P = 0.05). Our results suggest that the improved probe counting efficiency of the K-alpha probe design used in conjunction with the three-sigma statistical

  15. An Empirical Ultraviolet Iron Spectrum Template Applicable to Active Galaxies

    DEFF Research Database (Denmark)

    Vestergaard, Marianne; Wilkes, B. J.

    2001-01-01

    Iron emission is often a severe contaminant in optical-ultraviolet spectra of active galaxies. Its presence complicates emission line studies. A viable solution, already successfully applied at optical wavelengths, is to use an empirical iron emission template. We have generated FeII and FeIII te......, including iron transitions. Details of the data processing, generation, and use of the templates, are given by Vestergaard & Wilkes (2001)....

  16. Iron load

    Directory of Open Access Journals (Sweden)

    Filippo Cassarà

    2013-03-01

    Full Text Available Recent research addressed the main role of hepcidin in the regulation of iron metabolism. However, while this mechanism could be relevant in causing iron load in Thalassemia Intermedia and Sickle-Cell Anemia, its role in Thalassemia Major (TM is marginal. This is mainly due to the high impact of transfusional requirement into the severe increase of body iron. Moreover, the damage of iron load may be worsened by infections, as HCV hepatitis, or liver and endocrinological damage. One of the most relevant associations was found between splenectomy and increase of risk for mortality due,probably, to more severe iron load. These issues suggest as morbidity and mortality of this group of patients they do not depend only by our ability in controlling heart damage but even in preventing or treating particular infections and complications. This finding is supported by the impairment of survival curves in patients with complications different from heart damage. However, because, during recent years different direct and indirect methods to detect iron overload in patients affected by secondary hemochromatosis have been implemented, our ability to maintain under control iron load is significantly improved. Anyway, the future in iron load management remains to be able to have an iron load map of our body for targeting chelation and other medical treatment according to the single organ damage.

  17. Lipid raft facilitated ligation of K-{alpha}1-tubulin by specific antibodies on epithelial cells: Role in pathogenesis of chronic rejection following human lung transplantation

    Energy Technology Data Exchange (ETDEWEB)

    Tiriveedhi, Venkataswarup; Angaswamy, Nataraju [Department of Surgery, Pathology and Immunology, Washington University School of Medicine, St. Louis, MO (United States); Weber, Joseph [Department of Medicine, Washington University School of Medicine, St. Louis, MO (United States); Mohanakumar, T., E-mail: kumart@wustl.edu [Department of Surgery, Pathology and Immunology, Washington University School of Medicine, St. Louis, MO (United States)

    2010-08-20

    Research highlights: {yields} Addition of KAT Abs (+) sera to NHBE culture causes upregulation of growth factors. {yields} Cholesterol depletion causes down regulation of growth factor expression. {yields} Cholesterol depletion is accompanied by loss of membrane bound caveolin. {yields} Thus, we demonstrate lipid raft are critical for efficient ligation of the KAT Abs. -- Abstract: Long term function of human lung allografts is hindered by development of chronic rejection manifested as Bronchiolitis Obliterans Syndrome (BOS). We have previously identified the development of antibodies (Abs) following lung transplantation to K-{alpha}1-tubulin (KAT), an epithelial surface gap junction cytoskeletal protein, in patients who develop BOS. However, the biochemical and molecular basis of the interactions and signaling cascades mediated by KAT Abs are yet to be defined. In this report, we investigated the biophysical basis of the epithelial cell membrane surface interaction between KAT and its specific Abs. Towards this, we analyzed the role of the lipid raft-domains in the membrane interactions which lead to cell signaling and ultimately increased growth factor expression. Normal human bronchial epithelial (NHBE) cells, upon specific ligation with Abs to KAT obtained either from the serum of BOS(+) patients or monoclonal KAT Abs, resulted in upregulation of growth factors VEGF, PDGF, and bFGF (6.4 {+-} 1.1-, 3.2 {+-} 0.9-, and 3.4 {+-} 1.1-fold increase, respectively) all of which are important in the pathogenesis of BOS. To define the role for lipid raft in augmenting surface interactions, we analyzed the changes in the growth factor expression pattern upon depletion and enrichment with lipid raft following the ligation of the epithelial cell membranes with Abs specific for KAT. NHBE cells cultured in the presence of {beta}-methyl cyclodextran ({beta}MCD) had significantly reduced growth factor expression (1.3 {+-} 0.3, vs {beta}MCD untreated being 6.4 {+-} 1.1-fold

  18. Measuring the Kerr spin parameter of a non-Kerr compact object with the continuum-fitting and the iron line methods

    CERN Document Server

    Bambi, Cosimo

    2013-01-01

    Under the assumption that astrophysical black hole candidates are the Kerr black holes of general relativity, the continuum-fitting method and the analysis of the K$\\alpha$ iron line are today the only available techniques capable of providing a relatively reliable estimate of the spin parameter of these objects. If we relax the Kerr black hole hypothesis and we try to test the nature of black hole candidates, we find that there is a strong correlation between the measurement of the spin and possible deviations from the Kerr solution. The properties of the radiation emitted in a Kerr spacetime with spin parameter $a_*$ are indeed very similar, and practically indistinguishable, from the ones of the radiation emitted around a non-Kerr object with different spin. In this paper, I address the question whether measuring the Kerr spin with both the continuum-fitting method and the K$\\alpha$ iron line analysis of the same object can be used to claim the Kerr nature of the black hole candidate in the case of consist...

  19. Iron refractory iron deficiency anemia

    OpenAIRE

    De Falco, Luigia; Sanchez, Mayka; Silvestri, Laura; Kannengiesser, Caroline; Muckenthaler, Martina U; Iolascon, Achille; Gouya, Laurent; Camaschella, Clara; Beaumont, Carole

    2013-01-01

    Iron refractory iron deficiency anemia is a hereditary recessive anemia due to a defect in the TMPRSS6 gene encoding Matriptase-2. This protein is a transmembrane serine protease that plays an essential role in down-regulating hepcidin, the key regulator of iron homeostasis. Hallmarks of this disease are microcytic hypochromic anemia, low transferrin saturation and normal/high serum hepcidin values. The anemia appears in the post-natal period, although in some cases it is only diagnosed in ad...

  20. A pilot study for determining the optimal operation condition for simultaneously controlling the emissions of PCDD/Fs and PAHs from the iron ore sintering process.

    Science.gov (United States)

    Chen, Yu-Cheng; Tsai, Perng-Jy; Mou, Jin-Luh; Kuo, Yu-Chieh; Wang, Shih-Min; Young, Li-Hao; Wang, Ya-Fen

    2012-09-01

    In this study, the cost-benefit analysis technique was developed and incorporated into the Taguchi experimental design to determine the optimal operation combination for the purpose of providing a technique solution for controlling both emissions of PCDD/Fs and PAHs, and increasing both the sinter productivity (SP) and sinter strength (SS) simultaneously. Four operating parameters, including the water content, suction pressure, bed height, and type of hearth layer, were selected and all experimental campaigns were conducted on a pilot-scale sinter pot to simulate various sintering operating conditions of a real-scale sinter plant. The resultant optimal combination could reduce the total carcinogenic emissions arising from both emissions of PCDD/Fs and PAHs by 49.8%, and increase the sinter benefit associated with the increase in both SP and SS by 10.1%, as in comparison with the operation condition currently used in the real plant. The ANOVA results indicate that the suction pressure was the most dominant parameter in determining the optimal operation combination. The above result was theoretically plausible since the higher suction pressure provided more oxygen contents leading to the decrease in both PCDD/F and PAH emissions. But it should be noted that the results obtained from the present study were based on pilot scale experiments, conducting confirmation tests in a real scale plant are still necessary in the future. Copyright © 2012 Elsevier Ltd. All rights reserved.

  1. Acetaminophen protects against iron-induced cardiac damage in gerbils.

    Science.gov (United States)

    Walker, Ernest M; Epling, Christopher P; Parris, Cordel; Cansino, Silvestre; Ghosh, Protip; Desai, Devashish H; Morrison, Ryan G; Wright, Gary L; Wehner, Paulette; Mangiarua, Elsa I; Walker, Sandra M; Blough, Eric R

    2007-01-01

    There are few effective agents that safely remove excess iron from iron-overloaded individuals. Our goal was to evaluate the iron-removing effectiveness of acetaminophen given ip or orally in the gerbil iron-overload model. Male gerbils were divided into 5 groups: saline controls, iron-overloaded controls, iron-overloaded treated with ip acetaminophen, iron-overloaded treated with oral acetaminophen, and iron-overloaded treated with ipdeferoxamine. Iron dextran was injected iptwice/wk for 8 wk. Acetaminophen and deferoxamine treatments were given on Mondays, Wednesdays, and Fridays during the same 8 wk and continued for 4 wk after completion of iron-overloading. Echocardiograms were performed after completion of the iron-overloading and drug treatments. Liver and cardiac iron contents were determined by inductively coupled plasma atomic emission spectrometry (ICP-AES). Iron-overloaded controls had 232-fold and 16-fold increases in liver and cardiac iron content, respectively, compared to saline controls. In iron-overloaded controls, echocardiography showed cardiac hypertrophy, right and left ventricular distension, significant reduction in left ventricular ejection fraction (-22%), and fractional shortening (-31%) during systole. Treatments with acetaminophen (ip or oral) or deferoxamine (ip) were equally effective in reducing cardiac iron content and in preventing cardiac structural and functional changes. Both agents also significantly reduced excess hepatic iron content, although acetaminophen was less effective than deferoxamine. The results suggest that acetaminophen may be useful for treatment of iron-induced pathology.

  2. Cast irons

    CERN Document Server

    1996-01-01

    Cast iron offers the design engineer a low-cost, high-strength material that can be easily melted and poured into a wide variety of useful, and sometimes complex, shapes. This latest handbook from ASM covers the entire spectrum of one of the most widely used and versatile of all engineered materials. The reader will find the basic, but vital, information on metallurgy, solidification characteristics, and properties. Extensive reviews are presented on the low-alloy gray, ductile, compacted graphite, and malleable irons. New and expanded material has been added covering high-alloy white irons used for abrasion resistance and high-alloy graphitic irons for heat and corrosion resistance. Also discussed are melting furnaces and foundry practices such as melting, inoculation, alloying, pouring, gating and rising, and molding. Heat treating practices including stress relieving, annealing, normalizing, hardening and tempering, autempering (of ductile irons), and surface-hardening treatments are covered, too. ASM Spec...

  3. The Seyfert 2 galaxy NGC 2110: hard X-ray emission observed by NuSTAR and variability of the iron Kα line

    DEFF Research Database (Denmark)

    Marinucci, A.; Matt, G.; Bianchi, S.

    2015-01-01

    We present NuSTAR observations of the bright Seyfert 2 galaxy NGC 2110 obtained in 2012, when the source was at the highest flux level ever observed, and in 2013, when the source was at a more typical flux level. We include archival observations from other X-ray satellites, namely XMM-Newton, Suz......We present NuSTAR observations of the bright Seyfert 2 galaxy NGC 2110 obtained in 2012, when the source was at the highest flux level ever observed, and in 2013, when the source was at a more typical flux level. We include archival observations from other X-ray satellites, namely XMM...... is found and, by using temporal information collected over more than a decade, we investigate variations of the iron Kα line on time-scales of years. The Fe K alpha line is likely the sum of two components: one constant (originating from distant Compton-thick material) and the other one variable...

  4. Discoveries of Diffuse Iron Line Sources from the Sgr B Region

    CERN Document Server

    Koyama, K; Hyodo, Y; Matsumoto, H; Tsuru, T G; Maeda, Y; Murakami, H; Yamauchi, S; Kissel, S E; Soong, C Y; Koyama, Katsuji; Inui, Tatsuya; Hyodo, Yoshiaki; Matsumoto, Hironori; Tsuru, Takeshi Go; Maeda, Yoshitomo; Murakami, Hiroshi; Yamauchi, Shigeo; Kissel, Steven E.; Soong, Chan Yang

    2006-01-01

    The radio complex Sgr B region is observed with the X-Ray Imaging Spectrometers (XIS) on board Suzaku. This region exhibits diffuse iron lines at 6.4, 6.7 and 6.9 keV, which are K$\\alpha$ lines of Fe \\emissiontype{I} (neutral iron), Fe\\emissiontype{XXV} (He-like iron) and Fe\\emissiontype{XXVI} (H-like iron), respectively. The high energy resolving power of the XIS provides the separate maps of the K-shell transition lines from Fe\\emissiontype{I} (6.4 keV) and Fe\\emissiontype{XXV} (6.7 keV). Although the 6.7 keV line is smoothly distributed over the Sgr B region, a local excess is found near at $(l, b) = (\\timeform {0D.61}, \\timeform{0D.01})$, possibly a new SNR. The plasma temperature is \\textit{kT} $\\sim$3 keV and the age is estimated to be around several$\\times10^{3}$ years. The 6.4 keV image is clumpy with local excesses nearby Sgr B2 and at $(l, b) = (\\timeform{0D.74}, -\\timeform{0D.09})$. Like Sgr B2, this excess may be another candidate of an X-ray reflection nebula (XRN).

  5. 钢铁企业无组织排放特征污染物的监测分析%Monitoring and Analysis on Characteristic Pollutants of Fugitive Emission in Iron and Steel Enterprises

    Institute of Scientific and Technical Information of China (English)

    郭健; 马召坤; 李蕾; 吴彤

    2016-01-01

    The eastern old industrial area is the focus of pollution prevention and control in Jinan. Fugitive emissions of large enterprises in industrial areas have great impacts on air quality of regional and surrounding areas. It does not attracted much attention, because we do not know the size of emissions and types of pollutants, which makes it diffi cult to be controlled. Taking a large iron and steel enterprise of the eastern old industrial area in Jinan as an example, this paper selected five characteristic pollutants of monitoring sites, including benzene, toluene, xylene, non-methane hydrocarbons and ammonia. The variation of pollutants concentration under different weather conditions was analyzed to understand the characteristics of fugitive emissions in iron and steel enterprises. The results showed that the hourly concentration and daily average concentrations of downwind pollutants increased in varying degrees compared with upperwind area, indicating that the plant area sources had impacts on surrounding air quality. And then measures to prevent or improve air pollution were proposed, such as the tightened fugitive emissions standards, increased atmospheric monitoring sites and online monitoring projects, and recommend enterprises to strengthen the collection and processing aspects in the production process of fugitive emissions.%东部老工业区是济南市大气污染重点防控区域。工业区大型企业的无组织排放废气对区域及周边大气环境质量产生的影响,一直没有引起人们的足够重视,因对其排放量大小和污染物种类不清楚,难以进行监管。本文以济南东部老工业区一家大型钢铁企业为例,选取五项有代表性的特征污染物(苯、甲苯、二甲苯、非甲烷总烃和氨)进行布点监测,在不同气象条件下,分析特征污染物的浓度变化,了解钢铁企业无组织排放特征。经对监测数据的分析得出:与上风向相比,下风向各

  6. METABOLISM OF IRON STORES

    OpenAIRE

    Saito, Hiroshi

    2014-01-01

    ABSTRACT Remarkable progress was recently achieved in the studies on molecular regulators of iron metabolism. Among the main regulators, storage iron, iron absorption, erythropoiesis and hepcidin interact in keeping iron homeostasis. Diseases with gene-mutations resulting in iron overload, iron deficiency, and local iron deposition have been introduced in relation to the regulators of storage iron metabolism. On the other hand, the research on storage iron metabolism has not advanced since th...

  7. Soft X-ray emission studies of biomaterials

    Energy Technology Data Exchange (ETDEWEB)

    Kurmaev, E.Z. E-mail: kurmaev@ifmlrs.uran.ru; Werner, J.P.; Moewes, A.; Chiuzbaian, S.; Bach, M.; Ching, W.-Y.; Motozaki, W.; Otsuka, T.; Matsuya, S.; Endo, K.; Neumann, M

    2004-07-01

    Soft X-ray fluorescence measurements are used to characterize three groups of biomaterials: Vitamin B{sub 12} and derivatives, antioxidants (aspirin and paracetamol), and human teeth. We show that the chemical bonding in Vitamin B{sub 12} is characterized by the strong Co-C bond and the relatively weak Co-N bond. The Co-C bond in cyanocobalamin is found to be stronger than that of methylcobalamin leading to their different biological activity. The chemical bonding of paracetamol and aspirin is characterized by the formation of oxygen lone-pair {pi}-orbitals, which can neutralize free radicals and therefore be related to antioxidant activity of these compounds. Carbon K{alpha} emission spectra of a caries lesion suggest that the CaCO{sub 3} like phase exists in sound enamel and that a selective loss of carbonate occurs during the early stages of a caries attack.

  8. Iron Dextran Injection

    Science.gov (United States)

    ... allergic to iron dextran injection; any other iron injections such as ferric carboxymaltose (Injectafer), ferumoxytol (Feraheme), iron sucrose (Venofer), or sodium ferric gluconate (Ferrlecit);any other ...

  9. Radiolabeled cyclic arginine-glycine-aspartic (RGD)-conjugated iron oxide nanoparticles as single-photon emission computed tomography (SPECT) and magnetic resonance imaging (MRI) dual-modality agents for imaging of breast cancer

    Science.gov (United States)

    Deng, Shengming; Zhang, Wei; Zhang, Bin; Hong, Ruoyu; Chen, Qing; Dong, Jiajia; Chen, Yinyiin; Chen, Zhiqiang; Wu, Yiwei

    2015-01-01

    Ultrasmall superparamagnetic iron oxide nanoparticles (USPIOs) modified with a novel cyclic arginine-glycine-aspartate (RGD) peptide were made and radiolabeled as single-photon emission computed tomography (SPECT) and magnetic resonance imaging (MRI) dual-modality agents for imaging of breast cancer. The probe was tested both in vitro and in vivo to determine its receptor targeting efficacy and feasibility for SPECT and MRI. The radiochemical syntheses of 125I-cRGD-USPIO were accomplished with a radiochemical purity of 96.05 ± 0.33 %. High radiochemical stability was found in fresh human serum and in phosphate-buffered saline. The average hydrodynamic size of 125I-cRGD-USPIO determined by dynamic light scattering was 51.3 nm. Results of in vitro experiments verified the specificity of the radiolabeled nanoparticles to tumor cells. Preliminary biodistribution studies of 125I-radiolabeled cRGD-USPIO in Bcap37-bearing nude mice showed that it had long circulation half-life, high tumor uptake, and high initial blood retention with moderate liver uptake. In vivo tumor targeting and uptake of the radiolabeled nanoparticles in mice model were visualized by SPECT and MRI collected at different time points. Our results strongly indicated that the 125I-cRGD-USPIO could be used as a promising bifunctional radiotracer for early clinical tumor detection with high sensitivity and high spatial resolution by SPECT and MRI.

  10. Iron Sucrose Injection

    Science.gov (United States)

    Iron sucrose injection is used treat iron-deficiency anemia (a lower than normal number of red blood cells due ... and may cause the kidneys to stop working). Iron sucrose injection is in a class of medications called iron ...

  11. Iron-Deficiency Anemia

    Medline Plus

    Full Text Available ... enough iron, your body starts using the iron it has stored. Soon, the stored iron gets used ... fewer red blood cells. The red blood cells it does make have less hemoglobin than normal. Iron- ...

  12. Iron deficiency

    DEFF Research Database (Denmark)

    Schou, Morten; Bosselmann, Helle; Gaborit, Freja

    2015-01-01

    BACKGROUND: Both iron deficiency (ID) and cardiovascular biomarkers are associated with a poor outcome in heart failure (HF). The relationship between different cardiovascular biomarkers and ID is unknown, and the true prevalence of ID in an outpatient HF clinic is probably overlooked. OBJECTIVES.......043). CONCLUSION: ID is frequent in an outpatient HF clinic. ID is not associated with cardiovascular biomarkers after adjustment for traditional confounders. Inflammation, but not neurohormonal activation is associated with ID in systolic HF. Further studies are needed to understand iron metabolism in elderly HF...

  13. Testing the Kerr nature of black hole candidates using iron line reverberation mapping in the CPR framework

    CERN Document Server

    Jiang, Jiachen; Steiner, James F

    2016-01-01

    The iron K$\\alpha$ line commonly observed in the X-ray spectrum of black hole candidates is produced by X-ray fluorescence of the inner accretion disk. This line can potentially be quite a powerful tool to probe the spacetime geometry around these objects and test the Kerr black hole hypothesis. In a previous paper, we studied the ability to constrain possible deviations from the Kerr solution from the standard time-integrated iron line spectrum within the Cardoso-Pani-Rico framework. In the present work, we expand on that study and consider iron line reverberation mapping in the CPR framework. That is, we consider the time-evolution of the iron line profile in response to fluctuations in the X-ray primary source. Our simulations clearly show that the time information in reverberation mapping can better constrain the background metric than the time-integrated approach, and this is true, notably, for the deformation parameter $\\epsilon^r_3$, which is only weakly informed by a time-integrated observation.

  14. Missing Fe: hydrogenated iron nanoparticles

    CERN Document Server

    Bilalbegovic, G; Mohacek-Grosev, V

    2016-01-01

    Although it was found that the FeH lines exist in the spectra of some stars, none of the spectral features in the ISM have been assigned to this molecule. We suggest that iron atoms interact with hydrogen and produce Fe-H nanoparticles which sometimes contain many H atoms. We calculate infrared spectra of hydrogenated iron nanoparticles using density functional theory methods and find broad, overlapping bands. Desorption of H2 could induce spinning of these small Fe-H dust grains. Some of hydrogenated iron nanoparticles posses magnetic and electric moments and should interact with electromagnetic fields in the ISM. Fe_nH_m nanoparticles could contribute to the polarization of the ISM and the anomalous microwave emission. We discuss the conditions required to form FeH and Fe_nH_m in the ISM.

  15. Missing Fe: hydrogenated iron nanoparticles

    Science.gov (United States)

    Bilalbegović, G.; Maksimović, A.; Mohaček-Grošev, V.

    2017-03-01

    Although it was found that the FeH lines exist in the spectra of some stars, none of the spectral features in the interstellar medium (ISM) have been assigned to this molecule. We suggest that iron atoms interact with hydrogen and produce Fe-H nanoparticles which sometimes contain many H atoms. We calculate infrared spectra of hydrogenated iron nanoparticles using density functional theory methods and find broad, overlapping bands. Desorption of H2 could induce spinning of these small Fe-H dust grains. Some of hydrogenated iron nanoparticles possess magnetic and electric moments and should interact with electromagnetic fields in the ISM. FenHm nanoparticles could contribute to the polarization of the ISM and the anomalous microwave emission. We discuss the conditions required to form FeH and FenHm in the ISM.

  16. Iron bioavailability from commercially available iron supplements

    OpenAIRE

    2015-01-01

    Purpose Iron deficiency anaemia (IDA) is a global public health problem. Treatment with the standard of care ferrous iron salts may be poorly tolerated, leading to non-compliance and ineffective correction of IDA. Employing supplements with higher bioavailability might permit lower doses of iron to be used with fewer side effects, thus improving treatment efficacy. Here, we compared the iron bioavailability of ferrous sulphate tablets with alternative commercial iron products, including th...

  17. Transdermal iron replenishment therapy.

    Science.gov (United States)

    Modepalli, Naresh; Shivakumar, H N; Kanni, K L Paranjothy; Murthy, S Narasimha

    2015-01-01

    Iron deficiency anemia is one of the major nutritional deficiency disorders. Iron deficiency anemia occurs due to decreased absorption of iron from diet, chronic blood loss and other associated diseases. The importance of iron and deleterious effects of iron deficiency anemia are discussed briefly in this review followed by the transdermal approaches to deliver iron. Transdermal delivery of iron would be able to overcome the side effects associated with conventional oral and parenteral iron therapy and improves the patient compliance. During preliminary investigations, ferric pyrophosphate and iron dextran were selected as iron sources for transdermal delivery. Different biophysical techniques were explored to assess their efficiency in delivering iron across the skin, and in vivo studies were carried out using anemic rat model. Transdermal iron delivery is a promising approach that could make a huge positive impact on patients suffering with iron deficiency.

  18. Study of the Many Fluorescent Lines and the Absorption Variability in GX 301-2 with XMM-Newton

    Science.gov (United States)

    Fuerst, F.; Suchy, S.; Kreykenbohm, I.; Barragan, L.; Wilms, J.; Pottschmidt, K.; Caballero, I.; Kretschmar, P.; Ferrigno, C.; Rothschild, R. E.

    2011-01-01

    We present an in-depth study of the High Mass X-ray Binary (HMXB) GX 301-2 during its pre-periastron flare using data from the XMM-Newton satellite. The energy spectrum shows a power law continuum absorbed by a large equivalent hydrogen column on the order of 10(exp 24)/ sq cm and a prominent Fe K-alpha fluorescent emission line. Besides the Fe K-alpha line, evidence for Fe K-Beta, Ni K-alpha, Ni K-Beta, S K-alpha, Ar K-alpha, Ca K-alpha, and Cr K-alpha fluorescent lines is found. The observed line strengths are consistent with fluorescence in a cold absorber. This is the first time that Cr K-alpha is seen in emission in the X-ray spectrum of a HMXB. In addition to the modulation by the strong pulse period of approx 685 sec the source is highly variable and shows different states of activity. We perform time-resolved as well as pulse-to-pulse resolved spectroscopy to investigate differences between these states of activity. We find that fluorescent line fluxes are strongly variable and generally follow the overall flux. The N-H value is variable by a factor of 2, but not correlated to continuum normalization. We find an interval of low flux in the light curve in which the pulsations cease almost completely, without any indication of an increasing absorption column. We investigate this dip in detail and argue that it is most likely that during the dip the accretion ceased and the afterglow of the fluorescent iron accounted for the main portion of the X-ray flux. A similar dip was found earlier in RXTE data, and we compare our findings to these results.

  19. Iron and iron derived radicals

    Energy Technology Data Exchange (ETDEWEB)

    Borg, D.C.; Schaich, K.M.

    1987-04-01

    We have discussed some reactions of iron and iron-derived oxygen radicals that may be important in the production or treatment of tissue injury. Our conclusions challenge, to some extent, the usual lines of thought in this field of research. Insofar as they are born out by subsequent developments, the lessons they teach are two: Think fastexclamation Think smallexclamation In other words, think of the many fast reactions that can rapidly alter the production and fate of highly reactive intermediates, and when considering the impact of competitive reactions on such species, think how they affect the microenvironment (on the molecular scale) ''seen'' by each reactive molecule. 21 refs., 3 figs., 1 tab.

  20. Energy conservation and emissions reduction strategies in foundry industry

    OpenAIRE

    Li Yuanyuan; Chen Weiping; Huang Dan

    2010-01-01

    Current energy conservation and emissions reduction strategies in iron and steel industry were reviewed. Since foundry industry is one of the major source of energy consumption and pollution emission (especially CO2), issues concerning energy-saving and emission-reduction have been raised by governments and the industry. Specialists from around the world carried out multidimensional analyses and evaluation on the potentials in energy conservation and emissions reduction in iron and steel indu...

  1. Iron and stony-iron meteorites

    DEFF Research Database (Denmark)

    Benedix, Gretchen K.; Haack, Henning; McCoy, T. J.

    2014-01-01

    Without iron and stony-iron meteorites, our chances of ever sampling the deep interior of a differentiated planetary object would be next to nil. Although we live on a planet with a very substantial core, we will never be able to sample it. Fortunately, asteroid collisions provide us with a rich...... sampling of the deep interiors of differentiated asteroids. Iron and stony-iron meteorites are fragments of a large number of asteroids that underwent significant geological processing in the early solar system. Parent bodies of iron and some stony-iron meteorites completed a geological evolution similar...

  2. Iron-Deficiency Anemia

    Medline Plus

    Full Text Available ... or an inability to absorb enough iron from food. Overview Iron-deficiency anemia is a common type ... of the condition. Treatments may include dietary changes, medicines, and surgery. Severe iron-deficiency anemia may require ...

  3. Iron-Deficiency Anemia

    Medline Plus

    Full Text Available ... or an inability to absorb enough iron from food. Overview Iron-deficiency anemia is a common type ... condition. Treatments may include dietary changes, medicines, and surgery. Severe iron-deficiency anemia may require treatment in ...

  4. Iron-Deficiency Anemia

    Medline Plus

    Full Text Available ... at highest risk for iron-deficiency anemia. Outlook Doctors usually can successfully treat iron-deficiency anemia. Treatment ... poor skin tone, dizziness, and depression. After her doctor diagnosed her with iron-deficiency anemia, Susan got ...

  5. Iron and Your Child

    Science.gov (United States)

    ... extra iron in their diets. People following a vegetarian diet might also need additional iron. What's Iron ... as Whole Milk? About Anemia Minerals What's a Vegetarian? Word! Anemia Anemia Food Labels Vitamins and Minerals ...

  6. Iron-Deficiency Anemia

    Medline Plus

    Full Text Available ... Intramural Research Research Resources Research Meeting Summaries Technology Transfer Clinical Trials What Are Clinical Trials? Children & Clinical ... iron-deficiency anemia may require treatment in a hospital, blood transfusions , iron injections, or intravenous iron therapy. ...

  7. Genetics Home Reference: iron-refractory iron deficiency anemia

    Science.gov (United States)

    ... refractory iron deficiency anemia iron-refractory iron deficiency anemia Enable Javascript to view the expand/collapse boxes. ... All Close All Description Iron-refractory iron deficiency anemia is one of many types of anemia , which ...

  8. Unveiling the broad band X-ray continuum and iron line complex in Mkr 841

    CERN Document Server

    Petrucci, P O; Matt, G; Longinotti, A L; Malzac, J; Mouchet, M; Boisson, C; Maraschi, L; Nandra, K; Ferrando, P

    2007-01-01

    Mkr 841 is a bright Seyfert 1 galaxy known to harbor a strong soft excess and a variable K$\\alpha$ iron line. It has been observed during 3 different periods by XMM for a total cumulated exposure time of $\\sim$108 ks. We present in this paper a broad band spectral analysis of the complete EPIC-pn data sets. We were able to test two different models for the soft excess, a relativistically blurred photoionized reflection (\\r model) and a relativistically smeared ionized absorption (\\a model). The continuum is modeled by a simple cut-off power law and we also add a neutral reflection. These observations reveal the extreme and puzzling spectral and temporal behaviors of the soft excess and iron line. The 0.5-3 keV soft X-ray flux decreases by a factor 3 between 2001 and 2005 and the line shape appears to be a mixture of broad and narrow components. We succeed in describing this complex broad-band 0.5-10 keV spectral variability using either \\r or \\a to fit the soft excess. Both models give statistically equivalen...

  9. Fluorescent iron lines as a probe of astrophysical black hole systems

    CERN Document Server

    Reynolds, C S; Reynolds, Christopher S.; Nowak, Michael A.

    2003-01-01

    (abridged) With most physicists and astrophysicists in agreement that black holes do indeed exist, the focus of astrophysical black hole research has shifted to the detailed properties of these systems. Nature has provided us with an extremely useful probe of the region very close to an accreting black hole - X-ray irradiation of relatively cold material in the vicinity of the black hole can imprint characteristic features into the X-ray spectra of black hole systems, most notably the Kalpha fluorescent line of iron. Detailed X-ray spectroscopy of these features can be used to study Doppler and gravitational redshifts, thereby providing key information on the location and kinematics of the cold material. This is a powerful tool that allows us to probe within a few gravitational radii, or less, of the event horizon. Here, we present a comprehensive review of relativistic iron line studies for both accreting stellar mass black holes (i.e., Galactic Black Hole Candidate systems; GBHCs), and accreting supermassiv...

  10. Testing the Kerr metric with the iron line and the KRZ parametrization

    CERN Document Server

    Ni, Yueying; Bambi, Cosimo

    2016-01-01

    The spacetime geometry around astrophysical black holes is supposed to be well approximated by the Kerr metric, but deviations from the Kerr solution are predicted in a number of scenarios involving new physics. Broad iron K$\\alpha$ lines are commonly observed in the X-ray spectrum of black holes and originate by X-ray fluorescence of the inner accretion disk. The profile of the iron line is sensitively affected by the spacetime geometry in the strong gravity region and can be used to test the Kerr black hole hypothesis. In this paper, we extend previous work in the literature. In particular: i) as test-metric, we employ the parametrization recently proposed by Konoplya, Rezzolla, and Zhidenko, which has a number of subtle advantages with respect to the existing approaches; ii) we perform simulations with specific X-ray missions, and we consider NuSTAR as a prototype of current observational facilities and eXTP as an example of the next generation of X-ray observatories. We find a significant difference betwe...

  11. Iron bromide vapor laser

    Science.gov (United States)

    Sukhanov, V. B.; Shiyanov, D. V.; Trigub, M. V.; Dimaki, V. A.; Evtushenko, G. S.

    2016-03-01

    We have studied the characteristics of a pulsed gas-discharge laser on iron bromide vapor generating radiation with a wavelength of 452.9 nm at a pulse repetition frequency (PRF) of 5-30 kHz. The maximum output power amounted to 10 mW at a PRF within 5-15 kHz for a voltage of 20-25 kV applied to electrodes of the discharge tube. Addition of HBr to the medium produced leveling of the radial profile of emission. Initial weak lasing at a wavelength of 868.9 nm was observed for the first time, which ceased with buildup of the main 452.9-nm line.

  12. Iron from Zealandic bog iron ore -

    DEFF Research Database (Denmark)

    Lyngstrøm, Henriette Syrach

    2011-01-01

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

  13. Iron-refractory iron deficiency anemia.

    Science.gov (United States)

    Yılmaz Keskin, Ebru; Yenicesu, İdil

    2015-03-05

    Iron is essential for life because it is indispensable for several biological reactions, such as oxygen transport, DNA synthesis, and cell proliferation. Over the past few years, our understanding of iron metabolism and its regulation has changed dramatically. New disorders of iron metabolism have emerged, and the role of iron as a cofactor in other disorders has begun to be recognized. The study of genetic conditions such as hemochromatosis and iron-refractory iron deficiency anemia (IRIDA) has provided crucial insights into the molecular mechanisms controlling iron homeostasis. In the future, these advances may be exploited to improve treatment of both genetic and acquired iron disorders. IRIDA is caused by mutations in TMPRSS6, the gene encoding matriptase-2, which downregulates hepcidin expression under conditions of iron deficiency. The typical features of this disorder are hypochromic, microcytic anemia with a very low mean corpuscular volume of erythrocytes, low transferrin saturation, no (or inadequate) response to oral iron, and only a partial response to parenteral iron. In contrast to classic iron deficiency anemia, serum ferritin levels are usually low-normal, and serum or urinary hepcidin levels are inappropriately high for the degree of anemia. Although the number of cases reported thus far in the literature does not exceed 100, this disorder is considered the most common of the "atypical" microcytic anemias. The aim of this review is to share the current knowledge on IRIDA and increase awareness in this field.

  14. Iron-Refractory Iron Deficiency Anemia

    Science.gov (United States)

    Yılmaz Keskin, Ebru; Yenicesu, İdil

    2015-01-01

    Iron is essential for life because it is indispensable for several biological reactions, such as oxygen transport, DNA synthesis, and cell proliferation. Over the past few years, our understanding of iron metabolism and its regulation has changed dramatically. New disorders of iron metabolism have emerged, and the role of iron as a cofactor in other disorders has begun to be recognized. The study of genetic conditions such as hemochromatosis and iron-refractory iron deficiency anemia (IRIDA) has provided crucial insights into the molecular mechanisms controlling iron homeostasis. In the future, these advances may be exploited to improve treatment of both genetic and acquired iron disorders. IRIDA is caused by mutations in TMPRSS6, the gene encoding matriptase-2, which downregulates hepcidin expression under conditions of iron deficiency. The typical features of this disorder are hypochromic, microcytic anemia with a very low mean corpuscular volume of erythrocytes, low transferrin saturation, no (or inadequate) response to oral iron, and only a partial response to parenteral iron. In contrast to classic iron deficiency anemia, serum ferritin levels are usually low-normal, and serum or urinary hepcidin levels are inappropriately high for the degree of anemia. Although the number of cases reported thus far in the literature does not exceed 100, this disorder is considered the most common of the “atypical” microcytic anemias. The aim of this review is to share the current knowledge on IRIDA and increase awareness in this field. PMID:25805669

  15. Liver iron transport

    Institute of Scientific and Technical Information of China (English)

    Ross M Graham; Anita CG Chua; Carly E Herbison; John K Olynyk; Debbie Trinder

    2007-01-01

    The liver plays a central role in iron metabolism. It is the major storage site for iron and also expresses a complex range of molecules which are involved in iron transport and regulation of iron homeostasis. An increasing number of genes associated with hepatic iron transport or regulation have been identified. These include transferrin receptors (TFR1 and 2), a ferrireductase (STEAP3), the transporters divalent metal transporter-1 (DMT1) and ferroportin (FPN) as well as the haemochromatosis protein, HFE and haemojuvelin (HJV),which are signalling molecules. Many of these genes also participate in iron regulatory pathways which focus on the hepatic peptide hepcidin. However, we are still only beginning to understand the complex interactions between liver iron transport and iron homeostasis. This review outlines our current knowledge of molecules of iron metabolism and their roles in iron transport and regulation of iron homeostasis.

  16. [Iron-refractory iron deficiency anemia].

    Science.gov (United States)

    Kawabata, Hiroshi

    2016-02-01

    The major causes of iron deficiency anemia (IDA) include iron loss due to bleeding, increased iron requirements, and decreased iron absorption by the intestine. The most common cause of IDA in Japanese women is iron loss during menstruation. Autoimmune atrophic gastritis and Helicobacter pylori infection can also cause IDA by reducing intestinal iron absorption. In addition to these common etiologies, germline mutations of TMPRSS6 can cause iron-refractory IDA (IRIDA). TMPRSS6 encodes matriptase-2, a membrane-bound serine protease primarily expressed in the liver. Functional loss of matriptase-2 due to homozygous mutations results in an increase in the expression of hepcidin, which is the key regulator of systemic iron homeostasis. The serum hepcidin increase in turn leads to a decrease in iron supply from the intestine and macrophages to erythropoietic cells. IRIDA is microcytic and hypochromic, but decreased serum ferritin is not observed as in IDA. IRIDA is refractory to oral iron supplementation, but does respond to intravenous iron supplementation to some extent. Because genetic testing is required for the diagnoses of IRIDA, a considerable number of cases may go undiagnosed and may thus be overlooked.

  17. Nutritional iron deficiency

    NARCIS (Netherlands)

    Zimmermann, M.B.; Hurrell, R.F.

    2007-01-01

    Iron deficiency is one of the leading risk factors for disability and death worldwide, affecting an estimated 2 billion people. Nutritional iron deficiency arises when physiological requirements cannot be met by iron absorption from diet. Dietary iron bioavailability is low in populations consuming

  18. Iron deficiency anemia

    Science.gov (United States)

    Anemia - iron deficiency ... iron from old red blood cells. Iron deficiency anemia develops when your body's iron stores run low. ... You may have no symptoms if the anemia is mild. Most of the time, ... slowly. Symptoms may include: Feeling weak or tired more often ...

  19. Nutritional iron deficiency

    NARCIS (Netherlands)

    Zimmermann, M.B.; Hurrell, R.F.

    2007-01-01

    Iron deficiency is one of the leading risk factors for disability and death worldwide, affecting an estimated 2 billion people. Nutritional iron deficiency arises when physiological requirements cannot be met by iron absorption from diet. Dietary iron bioavailability is low in populations consuming

  20. Serum iron test

    Science.gov (United States)

    Fe+2; Ferric ion; Fe++; Ferrous ion; Iron - serum; Anemia - serum iron; Hemochromatosis - serum iron ... A blood sample is needed. Iron levels are highest in the morning. Your health care provider will likely have you do this test in the morning.

  1. Iron stress in plants.

    Science.gov (United States)

    Connolly, Erin L; Guerinot, Mary

    2002-07-30

    Although iron is an essential nutrient for plants, its accumulation within cells can be toxic. Plants, therefore, respond to both iron deficiency and iron excess by inducing expression of different gene sets. Here, we review recent advances in the understanding of iron homeostasis in plants gained through functional genomic approaches

  2. Iron stress in plants

    OpenAIRE

    Connolly, Erin L.; Guerinot, Mary Lou

    2002-01-01

    Although iron is an essential nutrient for plants, its accumulation within cells can be toxic. Plants, therefore, respond to both iron deficiency and iron excess by inducing expression of different gene sets. Here, we review recent advances in the understanding of iron homeostasis in plants gained through functional genomic approaches.

  3. Urinary iron excretion test in iron deficiency anemia.

    Directory of Open Access Journals (Sweden)

    Kimura,Ikuro

    1980-02-01

    Full Text Available A urinary iron excretion test was carried out in 22 patients with iron deficiency anemia. The iron excretion index was significantly higher in patients with intractable iron deficiency anemia compared with normal subjects and anemic patients who were responsive to iron therapy. The findings suggest that iron excretion may be a factor that modulates the response of patients to iron therapy.

  4. Iron and manganese emission standard for industrial wastewater discharge in Hunan province%湖南省工业废水中铁锰排放标准研究

    Institute of Scientific and Technical Information of China (English)

    张青梅; 马超; 向仁军; 刘湛; 陈灿

    2014-01-01

    The production process, waste water treatment technology, current situation of pollutant discharge of enterprises involving iron or manganese are investigated. The water of current polluted rivers in typical iron or manganese contaminated area of Hunan province is sampled and analysized. With reference to the international iron and manganese limits in the discharged waste water, this standard prescribes the limit of iron in wastewater discharged from existing enterprises is 10 mg/L; the limit of iron in wastewater discharged from new enterprises is 5 mg/L; the limit of manganese in wastewater discharged from enterprises is 1 mg/L.%通过对湖南省典型铁锰污染区域的钢铁、有色金属、电解锰及化工企业生产工艺、废水处理技术与污染物排放现状及受污染河流环境质量现状进行调查的基础上,参照国外废水中铁锰污染物排放限值,规定湖南省工业废水中现有企业总铁的排放标准限值为10 mg/L,新建企业废水中总铁排放标准限值为5 mg/L;湖南省工业废水中总锰的排放标准限值为1 mg/L.

  5. The Nature of Unresolved Soft X-ray Emission from the Galactic Disk

    CERN Document Server

    Masui, K; Yamasaki, N Y; Takei, Y; Kimura, S; Yoshino, T; McCammon, D

    2008-01-01

    Although about 40% of the soft X-ray background emission in 0.4 to 1 keV range has extragalactic origins and thus is totally blocked by the Galactic absorption in midplane directions, it decreases at most by about 20 % in midplane. Suzaku observation of the direction, (l, b) = (235, 0), showed an OVII Kalpha emission intensity comparable with that of the MBM-12 on cloud Suzaku observation, but revealed a narrow bump peaked at ~ 0.9 keV. The latter component is partly filling the decrease of the extragalactic component in midplane. The feature can be well represented by a thin thermal emission with a temperature of about 0.8 keV. Because of the high pressure implied for spatially extended hot gas, the emission is likely a sum of unresolved faint sources. We consider a large fraction of the emission originates from faint dM stars. We constructed a model spectrum for spatially unresolved dM stars that consistently explains the observed spectrum and the surface brightness. The model also suggests that the emissio...

  6. Ocean iron cycle

    Science.gov (United States)

    Boyd, Philip W.

    Interest in the biogeochemical cycle of iron has grown rapidly over the last two decades, due to the potential role of this element in modulating global climate in the geological past and ocean productivity in the present day. This trace metal has a disproportionately large effect (1 × 105 C:Fe) on photosynthetic carbon fixation by phytoplankton. In around one third of the open ocean, so-called high-nitrate low-chlorophyll (HNLC) regions, the resident phytoplankton have low growth rates despite an abundance of plant nutrients. This is due to the low supply of iron. Iron is present in the ocean in three phases, dissolved, colloidal, and particulate (biogenic and lithogenic). However, iron chemistry is complex with interactions between chemistry and biology such as the production of iron-binding siderophores by oceanic bacteria. This results in the interplay of inorganic chemistry, photochemistry, and organic complexation. Sources of new iron include dust deposition, upwelling of iron-rich deep waters, and the resuspension and lateral transport of sediments. Sinks for iron are mainly biological as evidenced by the vertical nutrient-like profile for dissolved iron in the ocean. Iron is rapidly recycled by the upper ocean biota within a so-called "ferrous wheel." The fe ratio [(new iron)/(new + regenerated iron)] provides an index of the relative supply of iron to the biota by new versus recycled iron. Over the last 15 years, interest in the potential role of iron in shaping climate in the geological past resulted in some of the most ambitious experiments in oceanography: large-scale (i.e., 50-1000 km2) iron enrichment of HNLC waters. They have provided valuable insights into how iron supply influences the biogeochemical cycles of elements such as carbon, sulfur, silicon, nitrogen, and phosphate.

  7. The Suzaku Hard X-ray Survey on the Galactic Center Region

    CERN Document Server

    Tsuru, T G; Nobukawa, M; Sawada, M; Ryu, S G; Fukuoka, R; Koyama, K

    2010-01-01

    Diffuse X-rays from the Galactic center (GC) region were found to exhibit many K-shell lines from iron and nickel atoms in the 6--9 keV band. The strong emission lines seen in the spectrum are neutral iron K$\\alpha$ at 6.4~keV, He-like iron K$\\alpha$ at 6.7~keV, H-like iron Ly$\\alpha$ at 6.9~keV, and He-like iron K$\\beta$ at 7.8~keV. Among them, the 6.4~keV emission line is a probe of non-thermal phenomena. We have detected strong 6.4~keV emission in several giant molecular clouds, some of which were newly discovered by Suzaku. All the spectra exhibit large equivalent widths of 1-2~keV and absorption columns of $2-10\\times 10^{23}\\{\\rm H\\ cm}^{-2}$. We found time variability of diffuse 6.4~keV emission in the Sgr B2 region comparing the maps and spectra obtained from 1994 to 2005 with ASCA, Chandra, XMM-Newton and Suzaku. We also report discovery of K$\\alpha$ lines of neutral argon, calcium, chrome, and manganese atoms in the Sgr~A region. We show that the equivalent width of the 6.4~keV emission line detecte...

  8. Iron-Deficiency Anemia

    Medline Plus

    Full Text Available ... This Content: NEXT >> Featured Video Living With and Managing Iron-Deficiency Anemia 05/18/2011 This video— ... treatment. For more information about living with and managing iron-deficiency anemia, go to the Health Topics ...

  9. Iron in diet

    Science.gov (United States)

    ... meat (especially beef) Oysters Poultry, dark red meat Salmon Tuna Whole grains Reasonable amounts of iron are ... iron up to three times. Foods rich in vitamin C ( such as citrus, strawberries, tomatoes, and potatoes) ...

  10. Iron-Deficiency Anemia

    Medline Plus

    Full Text Available ... iron-rich protein that carries oxygen from the lungs to the rest of the body. Iron-deficiency ... 2011 This video—presented by the National Heart, Lung, and Blood Institute, part of the National Institutes ...

  11. Iron-Deficiency Anemia

    Medline Plus

    Full Text Available ... deficiency anemia may require treatment in a hospital, blood transfusions , iron injections, or intravenous iron therapy. Rate This ... video—presented by the National Heart, Lung, and Blood Institute, part of the National ...

  12. Iron-Deficiency Anemia

    Medline Plus

    Full Text Available ... easily treated condition that occurs if you don't have enough iron in your body. Low iron ... can occur if your red blood cells don't contain enough hemoglobin (HEE-muh-glow-bin). Hemoglobin ...

  13. Iron-Deficiency Anemia

    Medline Plus

    Full Text Available ... muh-glow-bin). Hemoglobin is an iron-rich protein that carries oxygen from the lungs to the ... other complications. Infants and young children and women are the two groups at highest risk for iron- ...

  14. Iron-Deficiency Anemia

    Medline Plus

    Full Text Available ... severity of the condition. Treatments may include dietary changes, medicines, and surgery. Severe iron-deficiency anemia may require treatment in a hospital, blood ... With and Managing Iron-Deficiency Anemia 05/18/2011 This video— ...

  15. Iron-Deficiency Anemia

    Medline Plus

    Full Text Available ... Events Spokespeople Email Alerts E-Newsletters About NHLBI Organization NHLBI Director Budget, Planning, & Legislative Advisory Committees Jobs ... the body. Iron-deficiency anemia usually develops over time if your body doesn't have enough iron ...

  16. Iron supplements (image)

    Science.gov (United States)

    The mineral iron is an essential nutrient for humans because it is part of blood cells, which carry oxygen to all body cells. There is no conclusive evidence that iron supplements contribute to heart attacks.

  17. Iron-Deficiency Anemia

    Medline Plus

    Full Text Available ... easily treated condition that occurs if you don't have enough iron in your body. Low iron ... can occur if your red blood cells don't contain enough hemoglobin (HEE-muh-glow-bin). Hemoglobin ...

  18. Emission Trading

    OpenAIRE

    2009-01-01

    The work concerns Emission Trading Scheme from perspektive of taxes and accounting. I should show problems with emission trading. The work concerns practical example of trading with emission allowance.

  19. Iron age: novel targets for iron overload.

    Science.gov (United States)

    Casu, Carla; Rivella, Stefano

    2014-12-05

    Excess iron deposition in vital organs is the main cause of morbidity and mortality in patients affected by β-thalassemia and hereditary hemochromatosis. In both disorders, inappropriately low levels of the liver hormone hepcidin are responsible for the increased iron absorption, leading to toxic iron accumulation in many organs. Several studies have shown that targeting iron absorption could be beneficial in reducing or preventing iron overload in these 2 disorders, with promising preclinical data. New approaches target Tmprss6, the main suppressor of hepcidin expression, or use minihepcidins, small peptide hepcidin agonists. Additional strategies in β-thalassemia are showing beneficial effects in ameliorating ineffective erythropoiesis and anemia. Due to the suppressive nature of the erythropoiesis on hepcidin expression, these approaches are also showing beneficial effects on iron metabolism. The goal of this review is to discuss the major factors controlling iron metabolism and erythropoiesis and to discuss potential novel therapeutic approaches to reduce or prevent iron overload in these 2 disorders and ameliorate anemia in β-thalassemia.

  20. Iron deficiency anemia

    OpenAIRE

    Naigamwalla, Dinaz Z.; Webb, Jinelle A.; Giger, Urs

    2012-01-01

    Iron is essential to virtually all living organisms and is integral to multiple metabolic functions. The most important function is oxygen transport in hemoglobin. Iron deficiency anemia in dogs and cats is usually caused by chronic blood loss and can be discovered incidentally as animals may have adapted to the anemia. Severe iron deficiency is characterized by a microcytic, hypochromic, potentially severe anemia with a variable regenerative response. Iron metabolism and homeostasis will be ...

  1. Iron-Deficiency Anemia

    Science.gov (United States)

    ... page from the NHLBI on Twitter. What Is Iron-Deficiency Anemia? Español Iron-deficiency anemia is a common, ... Content: NEXT >> Featured Video Living With and Managing Iron-Deficiency Anemia 05/18/2011 This video—presented by ...

  2. Iron-Deficiency Anemia

    Science.gov (United States)

    ... the NHLBI on Twitter. What Is Iron-Deficiency Anemia? Español Iron-deficiency anemia is a common, easily ... Featured Video Living With and Managing Iron-Deficiency Anemia 05/18/2011 This video—presented by the ...

  3. Iron-Deficiency Anemia

    Medline Plus

    Full Text Available ... the NHLBI on Twitter. What Is Iron-Deficiency Anemia? Español Iron-deficiency anemia is a common, easily ... Featured Video Living With and Managing Iron-Deficiency Anemia 05/18/2011 This video—presented by the ...

  4. Iron-Deficiency Anemia

    Medline Plus

    Full Text Available ... the NHLBI on Twitter. What Is Iron-Deficiency Anemia? Español Iron-deficiency anemia is a common, easily ... Featured Video Living With and Managing Iron-Deficiency Anemia 05/18/2011 This video—presented by the ...

  5. Iron-Deficiency Anemia

    Medline Plus

    Full Text Available ... blood transfusions , iron injections, or intravenous iron therapy. Rate This Content: NEXT >> Featured Video Living With and Managing Iron-Deficiency Anemia 05/18/2011 This video—presented by the National Heart, Lung, and Blood Institute, part of the National ...

  6. Iron-Deficiency Anemia

    Medline Plus

    Full Text Available ... blood transfusions , iron injections, or intravenous iron therapy. Rate This Content: NEXT >> Featured Video Living With and Managing Iron-Deficiency Anemia 05/18/2011 This video—presented by the National Heart, Lung, and Blood Institute, part of the National ...

  7. Macrophages and Iron Metabolism.

    Science.gov (United States)

    Soares, Miguel P; Hamza, Iqbal

    2016-03-15

    Iron is a transition metal that due to its inherent ability to exchange electrons with a variety of molecules is essential to support life. In mammals, iron exists mostly in the form of heme, enclosed within an organic protoporphyrin ring and functioning primarily as a prosthetic group in proteins. Paradoxically, free iron also has the potential to become cytotoxic when electron exchange with oxygen is unrestricted and catalyzes the production of reactive oxygen species. These biological properties demand that iron metabolism is tightly regulated such that iron is available for core biological functions while preventing its cytotoxic effects. Macrophages play a central role in establishing this delicate balance. Here, we review the impact of macrophages on heme-iron metabolism and, reciprocally, how heme-iron modulates macrophage function.

  8. [Iron function and carcinogenesis].

    Science.gov (United States)

    Akatsuka, Shinya; Toyokuni, Shinya

    2016-07-01

    Though iron is an essential micronutrient for humans, the excess state is acknowledged to be associated with oncogenesis. For example, iron overload in the liver of the patients with hereditary hemocromatosis highly increases the risk of hepatocellular carcinoma. Also, as to asbestos-related mesothelioma, such kinds of asbestos with a higher iron content are considered to be more carcinogenic. Iron is a useful element, which enables fundamental functions for life such as oxygen carrying and electron transport. However, in the situation where organisms are unable to have good control of it, iron turns into a dangerous element which catalyzes generation of reactive oxygen. In this review, I first outline the relationships between iron and cancer in general, then give an explanation about iron-related animal carcinogenesis models.

  9. Simultaneous determination of arsenic, cadmium, calcium, chromium, cobalt, copper, iron, lead, magnesium, manganese, molybdenum, nickel, selenium, and zinc in fertilizers by microwave acid digestion and inductively coupled plasma-optical emission spectrometry detection: single-laboratory validation of a modification and extension of AOAC 2006.03.

    Science.gov (United States)

    Webb, Sharon; Bartos, James; Boles, Rhonda; Hasty, Elaine; Thuotte, Ethel; Thiex, Nancy J

    2014-01-01

    A single-laboratory validation study was conducted for the simultaneous determination of arsenic, cadmium, calcium, cobalt, copper, chromium, iron, lead, magnesium, manganese, molybdenum, nickel, selenium, and zinc in all major types of commercial fertilizer products by microwave digestion and inductively coupled plasma-optical emission spectroscopy analysis. This validation study proposes an extension and modification of AOAC 2006.03. The extension is the inclusion of calcium, copper, iron, magnesium, manganese, and zinc, and the modification is incorporation of hydrochloric acid in the digestion system. This dual acid digestion utilizes both hydrochloric and nitric acids in a 3 to 9 mL volume ratio/100 mL. In addition to 15 of the 30 original validation materials used in the 2006.03 collaborative study, National Institute of Standards and Technology Standard Reference Material 695 and Magruder 2009-06 were incorporated as accuracy materials. The main benefits of this proposed method are a significant increase in laboratory efficiency when compared to the use of both AOAC Methods 965.09 and 2006.03 to achieve the same objective and an enhanced recovery of several metals.

  10. Plant cell nucleolus as a hot spot for iron.

    Science.gov (United States)

    Roschzttardtz, Hannetz; Grillet, Louis; Isaure, Marie-Pierre; Conéjéro, Geneviève; Ortega, Richard; Curie, Catherine; Mari, Stéphane

    2011-08-12

    Many central metabolic processes require iron as a cofactor and take place in specific subcellular compartments such as the mitochondrion or the chloroplast. Proper iron allocation in the different organelles is thus critical to maintain cell function and integrity. To study the dynamics of iron distribution in plant cells, we have sought to identify the different intracellular iron pools by combining three complementary imaging approaches, histochemistry, micro particle-induced x-ray emission, and synchrotron radiation micro X-ray fluorescence. Pea (Pisum sativum) embryo was used as a model in this study because of its large cell size and high iron content. Histochemical staining with ferrocyanide and diaminobenzidine (Perls/diaminobenzidine) strongly labeled a unique structure in each cell, which co-labeled with the DNA fluorescent stain DAPI, thus corresponding to the nucleus. The unexpected presence of iron in the nucleus was confirmed by elemental imaging using micro particle-induced x-ray emission. X-ray fluorescence on cryo-sectioned embryos further established that, quantitatively, the iron concentration found in the nucleus was higher than in the expected iron-rich organelles such as plastids or vacuoles. Moreover, within the nucleus, iron was particularly accumulated in a subcompartment that was identified as the nucleolus as it was shown to transiently disassemble during cell division. Taken together, our data uncover an as yet unidentified although abundant iron pool in the cell, which is located in the nuclei of healthy, actively dividing plant tissues. This result paves the way for the discovery of a novel cellular function for iron related to nucleus/nucleolus-associated processes.

  11. New rat models of iron sucrose-induced iron overload.

    Science.gov (United States)

    Vu'o'ng Lê, Bá; Khorsi-Cauet, Hafida; Villegier, Anne-Sophie; Bach, Véronique; Gay-Quéheillard, Jérôme

    2011-07-01

    The majority of murine models of iron sucrose-induced iron overload were carried out in adult subjects. This cannot reflect the high risk of iron overload in children who have an increased need for iron. In this study, we developed four experimental iron overload models in young rats using iron sucrose and evaluated different markers of iron overload, tissue oxidative stress and inflammation as its consequences. Iron overload was observed in all iron-treated rats, as evidenced by significant increases in serum iron indices, expression of liver hepcidin gene and total tissue iron content compared with control rats. We also showed that total tissue iron content was mainly associated with the dose of iron whereas serum iron indices depended essentially on the duration of iron administration. However, no differences in tissue inflammatory and antioxidant parameters from controls were observed. Furthermore, only rats exposed to daily iron injection at a dose of 75 mg/kg body weight for one week revealed a significant increase in lipid peroxidation in iron-treated rats compared with their controls. The present results suggest a correlation between iron overload levels and the dose of iron, as well as the duration and frequency of iron injection and confirm that iron sucrose may not play a crucial role in inflammation and oxidative stress. This study provides important information about iron sucrose-induced iron overload in rats and may be useful for iron sucrose therapy for iron deficiency anemia as well as for the prevention and diagnosis of iron sucrose-induced iron overload in pediatric patients.

  12. Malabsorption of iron in children with iron deficiency.

    Science.gov (United States)

    Gross, S J; Stuart, M J; Swender, P T; Oski, F A

    1976-05-01

    Inability to absorb oral iron is believed to be an extremely rare cause of therapeutic failure in the treatment of iron deficiency anemia. Six patients who had failed to respond to oral iron therapy were studied by a simple oral absorption test and contrasted with 25 patients with untreated iron deficiency anemia and 10 normal subjects. All six of the patients who were therapeutic failures demonstrated impaired iron absorption in the absence of other clinical evidence of gastrointestinal disease. In the 25 newly diagnosed patients with iron deficiency. 24 demonstrated elevated iron absorptions while 10 ironreplete normal subjects had minimal elevations in their serum iron values following the administration of the test dose of 1 mg of elemental iron per kilogram. When the therapeutic failures were treated with parenteral iron, all had a therapeutic response. In addition, after treatment the impaired absorption of iron improved transiently. All children who absorbed iron readily responded to oral iron therapy.

  13. Iron chelating agents for iron overload diseases

    Directory of Open Access Journals (Sweden)

    Guido Crisponi

    2014-09-01

    Full Text Available Although iron is an essential element for life, an excessive amount may become extremely toxic both for its ability to generate reactive oxygen species, and for the lack in humans of regulatory mechanisms for iron excretion. Chelation therapy has been introduced in clinical practice in the seventies of last century to defend thalassemic patients from the effects of iron overload and, in spite of all its limitations, it has dramatically changed both life expectancy and quality of life of patients. It has to be considered that the drugs in clinical use present some disadvantages too, this makes urgent new more suitable chelating agents. The requirements of an iron chelator have been better and better defined over the years and in this paper they will be discussed in detail. As a final point the most interesting ligands studied in the last years will be presented.

  14. Influence of welding fume on systemic iron status.

    Science.gov (United States)

    Casjens, Swaantje; Henry, Jana; Rihs, Hans-Peter; Lehnert, Martin; Raulf-Heimsoth, Monika; Welge, Peter; Lotz, Anne; Gelder, Rainer Van; Hahn, Jens-Uwe; Stiegler, Hugo; Eisele, Lewin; Weiss, Tobias; Hartwig, Andrea; Brüning, Thomas; Pesch, Beate

    2014-11-01

    Iron is the major metal found in welding fumes, and although it is an essential trace element, its overload causes toxicity due to Fenton reactions. To avoid oxidative damage, excess iron is bound to ferritin, and as a result, serum ferritin (SF) is a recognized biomarker for iron stores, with high concentrations linked to inflammation and potentially also cancer. However, little is known about iron overload in welders. Within this study, we assessed the iron status and quantitative associations between airborne iron, body iron stores, and iron homeostasis in 192 welders not wearing dust masks. Welders were equipped with personal samplers in order to determine the levels of respirable iron in the breathing zone during a working shift. SF, prohepcidin and other markers of iron status were determined in blood samples collected after shift. The impact of iron exposure and other factors on SF and prohepcidin were estimated using multiple regression models. Our results indicate that respirable iron is a significant predictor of SF and prohepcidin. Concentrations of SF varied according to the welding technique and respiratory protection used, with a median of 103 μg l(-1) in tungsten inert gas welders, 125 μg l(-1) in those wearing air-purifying respirators, and 161 μg l(-1) in other welders. Compared to welders with low iron stores (SF < 25 μg l(-1)), those with excess body iron (SF ≥ 400 μg l(-1)) worked under a higher median concentration of airborne iron (60 μg m(-3) versus 148 μg m(-3)). Even though air concentrations of respirable iron and manganese were highly correlated, and low iron stores have been reported to increase manganese uptake in the gastrointestinal tract, no correlation was seen between SF and manganese in blood. In conclusion, monitoring SF may be a reasonable method for health surveillance of welders. Respiratory protection with air-purifying respirators can decrease iron exposure and avoid chronically higher SF in welders working with

  15. Iron deficiency anaemia.

    Science.gov (United States)

    Lopez, Anthony; Cacoub, Patrice; Macdougall, Iain C; Peyrin-Biroulet, Laurent

    2016-02-27

    Anaemia affects roughly a third of the world's population; half the cases are due to iron deficiency. It is a major and global public health problem that affects maternal and child mortality, physical performance, and referral to health-care professionals. Children aged 0-5 years, women of childbearing age, and pregnant women are particularly at risk. Several chronic diseases are frequently associated with iron deficiency anaemia--notably chronic kidney disease, chronic heart failure, cancer, and inflammatory bowel disease. Measurement of serum ferritin, transferrin saturation, serum soluble transferrin receptors, and the serum soluble transferrin receptors-ferritin index are more accurate than classic red cell indices in the diagnosis of iron deficiency anaemia. In addition to the search for and treatment of the cause of iron deficiency, treatment strategies encompass prevention, including food fortification and iron supplementation. Oral iron is usually recommended as first-line therapy, but the most recent intravenous iron formulations, which have been available for nearly a decade, seem to replenish iron stores safely and effectively. Hepcidin has a key role in iron homoeostasis and could be a future diagnostic and therapeutic target. In this Seminar, we discuss the clinical presentation, epidemiology, pathophysiology, diagnosis, and acute management of iron deficiency anaemia, and outstanding research questions for treatment.

  16. The ubiquity of iron.

    Science.gov (United States)

    Frey, Perry A; Reed, George H

    2012-09-21

    The importance of iron in living systems can be traced to the many complexes within which it is found, to its chemical mobility in undergoing oxidation-reduction reactions, and to the abundance of iron in Earth's crust. Iron is the most abundant element, by mass, in the Earth, constituting about 80% of the inner and outer cores of Earth. The molten outer core is about 8000 km in diameter, and the solid inner core is about 2400 km in diameter. Iron is the fourth most abundant element in Earth's crust. It is the chemically functional component of mononuclear iron complexes, dinuclear iron complexes, [2Fe-2S] and [4Fe-4S] clusters, [Fe-Ni-S] clusters, iron protophorphyrin IX, and many other complexes in protein biochemistry. Metals such as nickel, cobalt, copper, and manganese are present in the crust and could in principle function chemically in place of iron, but they are scarce in Earth's crust. Iron is plentiful because of its nuclear stability in stellar nuclear fusion reactions. It seems likely that other solid planets, formed by the same processes as Earth, would also foster the evolution of life and that iron would be similarly important to life on those planets as it is on Earth.

  17. XMM-Newton and Broad Iron Lines

    CERN Document Server

    Fabian, A C

    2007-01-01

    Iron line emission is common in the X-ray spectra of accreting black holes. When the line emission is broad or variable then it is likely to originate from close to the black hole. X-ray irradiation of the accretion flow by the power-law X-ray continuum produces the X-ray 'reflection' spectrum which includes the iron line. The shape and variability of the iron lines and reflection can be used as a diagnostic of the radius, velocity and nature of the flow. The inner radius of the dense flow corresponds to the innermost stable circular orbit and thus can be used to determine the spin of the black hole. Studies of broad iron lines and reflection spectra offer much promise for understanding how the inner parts of accretion flows (and outflows) around black holes operate. There remains great potential for XMM-Newton to continue to make significant progress in this work. The need for high quality spectra and thus for long exposure times is paramount.

  18. Brain iron homeostasis.

    Science.gov (United States)

    Moos, Torben

    2002-11-01

    Iron is essential for virtually all types of cells and organisms. The significance of the iron for brain function is reflected by the presence of receptors for transferrin on brain capillary endothelial cells. The transport of iron into the brain from the circulation is regulated so that the extraction of iron by brain capillary endothelial cells is low in iron-replete conditions and the reverse when the iron need of the brain is high as in conditions with iron deficiency and during development of the brain. Whereas there is good agreement that iron is taken up by means of receptor-mediated uptake of iron-transferrin at the brain barriers, there are contradictory views on how iron is transported further on from the brain barriers and into the brain extracellular space. The prevailing hypothesis for transport of iron across the BBB suggests a mechanism that involves detachment of iron from transferrin within barrier cells followed by recycling of apo-transferrin to blood plasma and release of iron as non-transferrin-bound iron into the brain interstitium from where the iron is taken up by neurons and glial cells. Another hypothesis claims that iron-transferrin is transported into the brain by means of transcytosis through the BBB. This thesis deals with the topic "brain iron homeostasis" defined as the attempts to maintain constant concentrations of iron in the brain internal environment via regulation of iron transport through brain barriers, cellular iron uptake by neurons and glia, and export of iron from brain to blood. The first part deals with transport of iron-transferrin complexes from blood to brain either by transport across the brain barriers or by uptake and retrograde axonal transport in motor neurons projecting beyond the blood-brain barrier. The transport of iron and transport into the brain was examined using radiolabeled iron-transferrin. Intravenous injection of [59Fe-125]transferrin led to an almost two-fold higher accumulation of 59Fe than of

  19. Colour Metallography of Cast Iron

    Institute of Scientific and Technical Information of China (English)

    Zhou Jiyang; Liu Jincheng

    2010-01-01

    @@ Chapter 3 Spheroidal Graphite Cast Iron(I) Spheroidal Graphite Cast Iron, SG iron in short, refers to the cast iron in which graphite precipitates as spheroidal shape during solidification of liquid iron. The graphite in common commercial cast iron can only be changed from flake to spheroidal shape by spheroidising treatment. Since spheroidal graphite reduces the cutting effect of stress concentration, the metal matrix strength of SG iron can be applied around 70%-90%, thus the mechanical property of SG iron is significantly superior to other cast irons;even the tensile strength of SG iron is higher than that carbon steel.

  20. Iron and Stony-iron Meteorites

    Science.gov (United States)

    Haack, H.; McCoy, T. J.

    2003-12-01

    Without iron and stony-iron meteorites, our chances of ever sampling the deep interior of a differentiated planetary object would be next to nil. Although we live on a planet with a very substantial core, we will never be able to sample it. Fortunately, asteroid collisions provide us with a rich sampling of the deep interiors of differentiated asteroids.Iron and stony-iron meteorites are fragments of a large number of asteroids that underwent significant geological processing in the early solar system. Parent bodies of iron and some stony-iron meteorites completed a geological evolution similar to that continuing on Earth - although on much smaller length- and timescales - with melting of the metal and silicates, differentiation into core, mantle, and crust, and probably extensive volcanism. Iron and stony-iron meteorites are our only available analogues to materials found in the deep interiors of Earth and other terrestrial planets. This fact has been recognized since the work of Chladni (1794), who argued that stony-iron meteorites must have originated in outer space and fallen during fireballs and that they provide our closest analogue to the material that comprises our own planet's core. This chapter deals with our current knowledge of these meteorites. How did they form? What can they tell us about the early evolution of the solar system and its solid bodies? How closely do they resemble the materials from planetary interiors? What do we know and don't we know?Iron and stony-iron meteorites constitute ˜6% of meteorite falls (Grady, 2000). Despite their scarcity among falls, iron meteorites are our only samples of ˜75 of the ˜135 asteroids from which meteorites originate ( Keil et al., 1994; Scott, 1979; Meibom and Clark, 1999; see also Chapter 1.05), suggesting that both differentiated asteroids and the geologic processes that produced them were common.Despite the highly evolved nature of iron and stony-iron meteorites, their chemistry provides important

  1. α-Synuclein Over-Expression Induces Increased Iron Accumulation and Redistribution in Iron-Exposed Neurons.

    Science.gov (United States)

    Ortega, Richard; Carmona, Asuncion; Roudeau, Stéphane; Perrin, Laura; Dučić, Tanja; Carboni, Eleonora; Bohic, Sylvain; Cloetens, Peter; Lingor, Paul

    2016-04-01

    Parkinson's disease is the most common α-synucleinopathy, and increased levels of iron are found in the substantia nigra of Parkinson's disease patients, but the potential interlink between both molecular changes has not been fully understood. Metal to protein binding assays have shown that α-synuclein can bind iron in vitro; therefore, we hypothesized that iron content and iron distribution could be modified in cellulo, in cells over-expressing α-synuclein. Owing to particle-induced X-ray emission and synchrotron X-ray fluorescence chemical nano-imaging, we were able to quantify and describe the iron distribution at the subcellular level. We show that, in neurons exposed to excess iron, the mere over-expression of human α-synuclein results in increased levels of intracellular iron and in iron redistribution from the cytoplasm to the perinuclear region within α-synuclein-rich inclusions. Reproducible results were obtained in two distinct recombinant expression systems, in primary rat midbrain neurons and in a rat neuroblastic cell line (PC12), both infected with viral vectors expressing human α-synuclein. Our results link two characteristic molecular features found in Parkinson's disease, the accumulation of α-synuclein and the increased levels of iron in the substantia nigra.

  2. Colour Metallography of Cast Iron

    Institute of Scientific and Technical Information of China (English)

    Zhou Jiyang; Liu Jincheng

    2010-01-01

    @@ Spheroidal Graphite Cast Iron(Ⅳ) 3.7 Segregation of SG iron The non-uniform distribution of solute elements during solidification results in the micro segregation of SG iron.As for the redistribution of elements in the phases of the solidification structure,there is no intrinsic difference between SG iron and grey iron[132].

  3. Cellular iron transport.

    Science.gov (United States)

    Garrick, Michael D; Garrick, Laura M

    2009-05-01

    Iron has a split personality as an essential nutrient that also has the potential to generate reactive oxygen species. We discuss how different cell types within specific tissues manage this schizophrenia. The emphasis in enterocytes is on regulating the body's supply of iron by regulating transport into the blood stream. In developing red blood cells, adaptations in transport manage the body's highest flux of iron. Hepatocytes buffer the body's stock of iron. Macrophage recycle the iron from effete red cells among other iron management tasks. Pneumocytes provide a barrier to prevent illicit entry that, when at risk of breaching, leads to a need to handle the dangers in a fashion essentially shared with macrophage. We also discuss or introduce cell types including renal cells, neurons, other brain cells, and more where our ignorance, currently still vast, needs to be removed by future research.

  4. Response of acid mobilization of iron-containing mineral dust to improvement of air quality projected in the future

    OpenAIRE

    Ito, A.; Xu, L.

    2013-01-01

    Acidification of dust aerosols may increase aerosol iron (Fe) solubility, which is linked to mineral properties. Combustion aerosols can also elevate aerosol iron solubility when aerosol loading is low. Here, we use an atmospheric chemical transport model to investigate the deposition of filterable iron and its response to changes in anthropogenic emissions of both combustion aerosols and precursor gases. By introducing three classes of iron-containing minerals into the detailed aeroso...

  5. Response of acid mobilization of iron-containing mineral dust to improvement of air quality projected in the future

    OpenAIRE

    2014-01-01

    Acidification of dust aerosols may increase aerosol iron (Fe) solubility, which is linked to mineral properties. Combustion aerosols can also elevate aerosol iron solubility when aerosol loading is low. Here, we use an atmospheric chemical transport model to investigate the deposition of filterable iron and its response to changes in anthropogenic emissions of both combustion aerosols and precursor gases. By introducing three classes of iron-containing minerals into the deta...

  6. Austempered Ductile Iron Machining

    Science.gov (United States)

    Pilc, Jozef; Šajgalík, Michal; Holubják, Jozef; Piešová, Marianna; Zaušková, Lucia; Babík, Ondrej; Kuždák, Viktor; Rákoci, Jozef

    2015-12-01

    This article deals with the machining of cast iron. In industrial practice, Austempered Ductile Iron began to be used relatively recently. ADI is ductile iron that has gone through austempering to get improved properties, among which we can include strength, wear resistance or noise damping. This specific material is defined also by other properties, such as high elasticity, ductility and endurance against tenigue, which are the properties, that considerably make the tooling characteristic worse.

  7. Iron and the athlete.

    Science.gov (United States)

    Suedekum, Natalie A; Dimeff, Robert J

    2005-08-01

    Iron is an important mineral necessary for many biologic pathways. Different levels of deficiency can occur in the athlete, resulting in symptoms that range from none to severe fatigue. Iron deficiency without anemia may adversely affect athletic performance. Causes of iron deficiency include poor intake, menstrual losses, gastrointestinal and genitourinary losses due to exercise-induced ischemia or organ movement, foot strike hemolysis, thermohemolysis, and sweat losses. A higher incidence of deficiency occurs in female athletes compared with males.

  8. Physics of iron

    Energy Technology Data Exchange (ETDEWEB)

    Anderson, O.

    1993-10-01

    This volume comprises papers presented at the AIRAPT Conference, June 28 to July 1993. The iron sessions at the meeting were identified as the Second Ironworkers Convention. The renewal of interest stems from advances in technologies in both diamond-anvil cell (DAC) and shock wave studies as well as from controversies arising from a lack of consensus among both experimentalists and theoreticians. These advances have produced new data on iron in the pressure-temperature regime of interest for phase diagrams and for temperatures of the core/mantle and inner-core/outer-core boundaries. Particularly interesting is the iron phase diagram inferred from DAC studies. A new phase, {beta}, with a {gamma}-{beta}-{epsilon} triple point at about 30 GPa and 1190 K, and possible sixth phase, {omega}, with an {epsilon}-{Theta}-melt triple point at about 190 GPa and 4000 K are deemed possible. The importance of the equation of state of iron in consideration of Earth`s heat budget and the origin of its magnetic field invoke the interest of theoreticians who argue on the basis of molecular dynamics and other first principles methods. While the major thrust of both meetings was on the physics of pure iron, there was notable contributions on iron alloys. Hydrogen-iron alloys, iron-sulfur liquids, and the comparability to rhenium in phase diagram studies are discussed. The knowledge of the physical properties of iron were increased by several contributions.

  9. Iron, Meat and Health

    Directory of Open Access Journals (Sweden)

    Catherine Geissler

    2011-02-01

    Full Text Available This article is a summary of the publication “Iron and Health” by the Scientific Advisory Committee on Nutrition (SACN to the U.K. Government (2010, which reviews the dietary intake of iron and the impact of different dietary patterns on the nutritional and health status of the U.K. population. It concludes that several uncertainties make it difficult to determine dose-response relationships or to confidently characterize the risks associated with iron deficiency or excess. The publication makes several recommendations concerning iron intakes from food, including meat, and from supplements, as well as recommendations for further research.

  10. Recalling the Iron Girls

    Institute of Scientific and Technical Information of China (English)

    1998-01-01

    The phrase "iron girl" is symbolic of an era. Widely used in the 1960s and the early 1970s, it was a term that described women who, in the spirit of sexual equality, found in themselves a physical strength that surpassed their psychologi cal expectations. With their might and power, they proved to society that women could do everything that men could. The title of "iron girl" was their pride.The well-known writer Fan Xiaoqing, was one such iron girl. She says the "iron girls" were nothing less than a quest for perfection.

  11. Iron overload and immunity

    Institute of Scientific and Technical Information of China (English)

    Gra(c)a Porto; Maria De Sousa

    2007-01-01

    Progress in the characterization of genes involved in the control of iron homeostasis in humans and in mice has improved the definition of iron overload and of the cells affected by it. The cell involved in iron overload with the greatest effect on immunity is the macrophage.Intriguing evidence has emerged, however, in the last 12 years indicating that parenchymal iron overload is linked to genes classically associated with the immune system. This review offers an update of the genes and proteins relevant to iron metabolism expressed in cells of the innate immune system, and addresses the question of how this system is affected in clinical situations of iron overload. The relationship between iron and the major cells of adaptive immunity, the T lymphocytes,will also be reviewed. Most studies addressing this last question in humans were performed in the clinical model of Hereditary Hemochromatosis. Data will also be reviewed demonstrating how the disruption of molecules essentially involved in adaptive immune responses result in the spontaneous development of iron overload and how they act as modifiers of iron overload.

  12. Benefits and harms of iron supplementation in iron-deficient and iron-sufficient children.

    Science.gov (United States)

    Domellöf, Magnus

    2010-01-01

    Due to high iron requirements, young children are at risk for iron deficiency anemia. Iron supplements are therefore often recommended, especially since iron deficiency anemia in children is associated with poor neurodevelopment. However, in contrast to most other nutrients, excess iron cannot be excreted by the human body and it has recently been suggested that excessive iron supplementation of young children may have adverse effects on growth, risk of infections, and even on cognitive development. Recent studies support that iron supplements are beneficial in iron-deficient children but there is a risk of adverse effects in those who are iron replete. In populations with a low prevalence of iron deficiency, general supplementation should therefore be avoided. Iron-fortified foods can still be generally recommended since they seem to be safer than medicinal iron supplements, but the level of iron fortification should be limited. General iron supplementation is recommended in areas with a high prevalence of iron deficiency, with the exception of malarious areas where a cautious supplementation approach needs to be adopted, based either on screening or a combination of iron supplements and infection control measures. More studies are urgently needed to better determine the risks and benefits of iron supplementation and iron-fortified foods given to iron-deficient and iron-sufficient children.

  13. Emissions Trading

    NARCIS (Netherlands)

    Woerdman, Edwin; Backhaus, Juergen

    2014-01-01

    Emissions trading is a market-based instrument to achieve environmental targets in a cost-effective way by allowing legal entities to buy and sell emission rights. The current international dissemination and intended linking of emissions trading schemes underlines the growing relevance of this

  14. Emissions Trading

    NARCIS (Netherlands)

    Woerdman, Edwin; Backhaus, Juergen

    2014-01-01

    Emissions trading is a market-based instrument to achieve environmental targets in a cost-effective way by allowing legal entities to buy and sell emission rights. The current international dissemination and intended linking of emissions trading schemes underlines the growing relevance of this instr

  15. [Iron deficiency and digestive disorders].

    Science.gov (United States)

    Cozon, G J N

    2014-11-01

    Iron deficiency anemia still remains problematic worldwide. Iron deficiency without anemia is often undiagnosed. We reviewed, in this study, symptoms and syndromes associated with iron deficiency with or without anemia: fatigue, cognitive functions, restless legs syndrome, hair loss, and chronic heart failure. Iron is absorbed through the digestive tract. Hepcidin and ferroportin are the main proteins of iron regulation. Pathogenic micro-organisms or intestinal dysbiosis are suspected to influence iron absorption. Copyright © 2014 Elsevier Masson SAS. All rights reserved.

  16. Emission Facilities - Air Emission Plants

    Data.gov (United States)

    NSGIC Education | GIS Inventory — Represents the Primary Facility type Air Emission Plant (AEP) point features. Air Emissions Plant is a DEP primary facility type related to the Air Quality Program....

  17. Emission Facilities - Air Emission Plants

    Data.gov (United States)

    NSGIC GIS Inventory (aka Ramona) — Represents the Primary Facility type Air Emission Plant (AEP) point features. Air Emissions Plant is a DEP primary facility type related to the Air Quality Program....

  18. Emission inventory; Inventaire des emissions

    Energy Technology Data Exchange (ETDEWEB)

    Fontelle, J.P. [CITEPA, Centre Interprofessionnel Technique d`Etudes de la Pollution Atmospherique, 75 - Paris (France)

    1997-12-31

    Statistics on air pollutant (sulfur dioxide, nitrogen oxides and ammonium) emissions, acid equivalent emissions and their evolution since 1990 in the various countries of Europe and the USA, are presented. Emission data from the industrial, agricultural, transportation and power sectors are given, and comparisons are carried out between countries based on Gnp and population, pollution import/export fluxes and compliance to the previous emission reduction objectives

  19. Colour Metallography of Cast Iron

    Institute of Scientific and Technical Information of China (English)

    Zhou Jiyang; Liu Jincheng

    2011-01-01

    White Cast Iron (Ⅰ) White cast iron or ‘white iron' refers to the type of cast iron in which all of the carbon exists as carbide;there is no graphite in the as-cast structure and the fractured surface shows a white colour.White cast iron can be divided in three classes:· Normal white cast iron — this iron contains only C,Si,Mn,P and S,with no other alloying elements.· Low-alloy white cast iron — the total mass fraction of alloying elements is less than 5%.

  20. Iron-Deficiency Anemia

    Medline Plus

    Full Text Available ... Blood Tests Blood Transfusion Restless Legs Syndrome Send a link to NHLBI to someone by E-MAIL | ... Iron-Deficiency Anemia? Español Iron-deficiency anemia is a common, easily treated condition that occurs if you ...

  1. Total iron binding capacity

    Science.gov (United States)

    ... the intestines not properly absorbing vitamin B12 ( pernicious anemia ) Sickle cell anemia Risks There is very little risk involved with ... test Hemoglobin Hemolytic anemia Iron deficiency anemia Pernicious anemia Serum iron test Sickle cell anemia Review Date 2/11/2016 Updated by: ...

  2. Thin Wall Iron Castings

    Energy Technology Data Exchange (ETDEWEB)

    J.F. Cuttino; D.M. Stefanescu; T.S. Piwonka

    2001-10-31

    Results of an investigation made to develop methods of making iron castings having wall thicknesses as small as 2.5 mm in green sand molds are presented. It was found that thin wall ductile and compacted graphite iron castings can be made and have properties consistent with heavier castings. Green sand molding variables that affect casting dimensions were also identified.

  3. Iron-Deficiency Anemia

    Medline Plus

    Full Text Available ... periods. By following her treatment plan and making smart lifestyle choices, Susan continues to feel better and see the benefits of treatment. For more information about living with and managing iron-deficiency anemia, go to the Health Topics Iron-Deficiency Anemia article. Updated: March 26, ...

  4. Iron deficiency in childhood

    NARCIS (Netherlands)

    Uijterschout, L.

    2015-01-01

    Iron deficiency (ID) is the most common micronutrient deficiency in the world. Iron is involved in oxygen transport, energy metabolism, immune response, and plays an important role in brain development. In infancy, ID is associated with adverse effects on cognitive, motor, and behavioral development

  5. Iron-Deficiency Anemia

    Medline Plus

    Full Text Available ... Blood Tests Blood Transfusion Restless Legs Syndrome Send a link to NHLBI to someone by E-MAIL | ... Iron-Deficiency Anemia? Español Iron-deficiency anemia is a common, easily treated condition that occurs if you ...

  6. Iron deficiency in childhood

    NARCIS (Netherlands)

    Uijterschout, L.

    2015-01-01

    Iron deficiency (ID) is the most common micronutrient deficiency in the world. Iron is involved in oxygen transport, energy metabolism, immune response, and plays an important role in brain development. In infancy, ID is associated with adverse effects on cognitive, motor, and behavioral development

  7. Iron-Deficiency Anemia

    Medline Plus

    Full Text Available ... Deficiency Anemia? Español Iron-deficiency anemia is a common, easily treated condition that occurs if you don' ... from food. Overview Iron-deficiency anemia is a common type of anemia . The term "anemia" usually refers ...

  8. Chemical composition analysis of raw materials used in iron ore sinter plants in Poland

    Directory of Open Access Journals (Sweden)

    D. Burchart-Korol

    2014-07-01

    Full Text Available The main goal of the study was the analysis of the chemical compositions of raw materials used in iron ore sinter plants in Poland. The iron ore sintering process is the largest source of emissions of dust and gas pollution in the iron and steel industry. Hematite ores, magnetite concentrates, admixtures (dolomite, limestone and burnt lime, fuels (coke breeze, anthracite and by-products are used in Poland to produce the sinter mixture.

  9. A focussing iron line crystal spectrometer for Spacelab. [cosmic X-ray detection

    Science.gov (United States)

    Catura, R. C.; Culhane, J. L.; Rapley, C. G.; Gabriel, A. H.; Walker, A. B. C., Jr.; Woodgate, B. E.

    1977-01-01

    A crystal spectrometer system is described which employs conical focusing of 12 curved LiF crystal panels to minimize the detector size and reduce the background counting rate. The wavelength range from 1.70 to 1.98 A is covered, including the resonance lines of Fe XXV and Fe XXVI as well as the Fe I K-alpha line and absorption edge. Operation of the spectrometer is discussed, noting that diffracted X-rays are registered in one-dimensional position-sensitive detectors and that the arrival position of a photon in a detector is related to its wavelength due to the fixed curvature of the crystal panels in the dispersion plane. Some characteristics of the multianode position-sensitive detectors are reviewed along with the crystal arrangement and mounting. The instrument sensitivity is evaluated in relation to the strengths of 6.7-keV emission features detected by the Ariel 5 and OSO 8 proportional-counter spectrometers.

  10. Impact of iron porphyrin complexes when hydroprocessing algal HTL biocrude

    Energy Technology Data Exchange (ETDEWEB)

    Jarvis, Jacqueline M.; Sudasinghe, Nilusha M.; Albrecht, Karl O.; Schmidt, Andrew J.; Hallen, Richard T.; Anderson, Daniel B.; Billing, Justin M.; Schaub, Tanner M.

    2016-10-01

    We apply Fourier transform ion cyclotron resonance mass spectrometry (FT-ICR MS) for direct characterization of iron-porphyrins in hydrothermal liquefaction (HTL) biocrude oils derived from two algae: Tetraselmis sp. and cyanobacteria. The ironporphyrin compounds are shown to cause catalyst bed plugging during hydroprocessing due to iron deposition. Inductively-coupled plasma optical emission spectrometry (ICPOES) was utilized for iron quantitation in the plugged catalyst beds formed through hydroprocessing of the two HTL biocrudes and identifies an enrichment of iron in the upper five centimeters of the catalyst bed for Tetraselmis sp. (Fe=100,728 ppm) and cyanobacteria (Fe=115,450 ppm). Direct infusion FT-ICR MS analysis of the two HTL biocrudes with optimized instrument conditions facilitates rapid screening and identification of iron-porphyrins without prior chromatographic separation. With FT-ICR MS we identify 138 unique iron-porphyrin compounds in the two HTL biocrudes that are structurally similar to metal-porphyrins (e.g. Ni and V) observed in petroleum. No ironporphyrins are observed in the cyanobacteria HTL biocrude after hydroprocessing, which indicates that iron-porphyrin structures in the HTL biocrude are degraded during hydroprocessing. Hydrodemetallization reactions that occur through hydroprocessing of HTL biocrudes could be responsible for the decomposition of iron-porphyrin structures leading to metal deposition in the catalyst bed that result in catalyst deactivation and bed plugging, and must be addressed for effective upgrading of algal HTL biocrudes.

  11. Microbes: mini iron factories.

    Science.gov (United States)

    Joshi, Kumar Batuk

    2014-12-01

    Microbes have flourished in extreme habitats since beginning of the Earth and have played an important role in geological processes like weathering, mineralization, diagenesis, mineral formation and destruction. Biotic mineralization is one of the most fascinating examples of how microbes have been influencing geological processes. Iron oxidizing and reducing bacteria are capable of precipitating wide varieties of iron oxides (magnetite), carbonates (siderite) and sulphides (greigite) via controlled or induced mineralization processes. Microbes have also been considered to play an important role in the history of evolution of sedimentary rocks on Earth from the formation of banded iron formations during the Archean to modern biotic bog iron and ochre deposits. Here, we discuss the role that microbes have been playing in precipitation of iron and the role and importance of interdisciplinary studies in the field of geology and biology in solving some of the major geological mysteries.

  12. Study on dioxin emission inhibition effect by addition of two inhibitors in iron ore sintering process%两种抑制剂对铁矿石烧结过程二(口恶)(口英)减排研究

    Institute of Scientific and Technical Information of China (English)

    戴帆; 谈琰; 李咸伟; 俞勇梅; 何晓蕾; 陈德珍

    2012-01-01

    The inhibition effects on dioxin emission from iron ore sintering process were compared for two inhibitors through a series of sintering-pot experiments. The additions of the two inhibitors, namely urea and carbohydrazide, in the sintering iron ore mixture were arranged as 0.01%, 0.02%, 0.05% and 0.1% (ω) respectively. The results showed that both inhibitors can reduce dioxin emission significantly. For the case of urea inhibitor, the reduction efficiencies of dioxin emission fluctuated with its addition with the highest efficiency 67.74% appeared at the addition of 0.02%; while for carbohydrazide inhibitor the reduction efficiencies of dioxin emission increased with its addition and the highest efficiency reached 78.79% as 0.1% of carbohydrazide was added. Both inhibitors did not change the finger print of dioxin homologues. The inhibition effect on all dioxin homologues formation by urea was coincident with that by carbohydrazide, namely, the isomer distribution of dioxin emissions were not essentially changed except that OCDD and OCDF behaved different for the two inhibitors. Both inhibitors did not change sintering indexs significantly.%研究了尿素和碳酰肼对烧结过程二噁英减排的影响,添加量分别是0.01%,0.02%,0.05%,0.1%(ω:质量浓度).结果表明,两者均对二(口恶)(口英)减排效果显著,其中,尿素对应的减排率随尿素的加入量有所波动,加入量为0.02%时,二噁嗔的毒性当量排放浓度减少了67.74%,为实验最高值.碳酰肼对应的减排率在实验范围内随加入量升高而升高,在最高加入量0.1%处二(口恶)(口英)的毒性当量排放浓度减少了78.79%.两种抑制剂都没有改变二(口恶)(口英)同系物的分布规律,对铁矿烧结过程二(口恶)(口英)同系物形成的抑制作用在绝大范围内是一致的,只有OCDD与OCDF表现出差异性.添加极少量的尿素和肼这2种抑制剂不会给烧结生产带来明显的影响.

  13. Measurement of Iron in Egg Yolk: An Instrumental Analysis Experiment Using Biochemical Principles

    Science.gov (United States)

    Maloney, Kevin M.; Quiazon, Emmanuel M.; Indralingam, Ramee

    2008-01-01

    The generally accepted method to determine iron content in food is by acid digestion or dry ashing and subsequent flame atomic absorption spectrometry or inductively coupled plasma atomic emission spectrometry. We have developed an experiment that chemically extracts the iron from an egg yolk and quantifies it using UV-vis absorption…

  14. Spatial patterns of iron- and methane-oxidizing bacterial communities in an irregularly flooded, riparian wetland

    NARCIS (Netherlands)

    Wang, J.; Krause, S.; Muyzer, G.; Meima-Franke, M.; Laanbroek, H.J.; Bodelier, P.L.E.

    2012-01-01

    Iron- and methane-cycling are important processes in wetlands with one connected to plant growth and the other to greenhouse gas emission, respectively. In contrast to acidic habitats, there is scarce information on the ecology of microbes oxidizing ferrous iron at circumneutral pH. The latter is

  15. Measurement of Iron in Egg Yolk: An Instrumental Analysis Experiment Using Biochemical Principles

    Science.gov (United States)

    Maloney, Kevin M.; Quiazon, Emmanuel M.; Indralingam, Ramee

    2008-01-01

    The generally accepted method to determine iron content in food is by acid digestion or dry ashing and subsequent flame atomic absorption spectrometry or inductively coupled plasma atomic emission spectrometry. We have developed an experiment that chemically extracts the iron from an egg yolk and quantifies it using UV-vis absorption…

  16. Iron and the endurance athlete.

    Science.gov (United States)

    Hinton, Pamela S

    2014-09-01

    Iron is a trace mineral that is highly significant to endurance athletes. Iron is critical to optimal athletic performance because of its role in energy metabolism, oxygen transport, and acid-base balance. Endurance athletes are at increased risk for suboptimal iron status, with potential negative consequences on performance, because of the combination of increased iron needs and inadequate dietary intake. This review paper summarizes the role of iron in maximal and submaximal exercise and describes the effects of iron deficiency on exercise performance. Mechanisms that explain the increased risk of iron deficiency in endurance athletes, including exercise-associated inflammation and hepcidin release on iron sequestration, are described. Information on screening athletes for iron deficiency is presented, and suggestions to increase iron intake through diet modification or supplemental iron are provided.

  17. 碱熔融电感耦合等离子体原子发射光谱法测定生铁中硅锰磷含量%Determination of Silicon Manganese and Phosphorus in Pig Iron with Inductively Coupled Plasma Atomic Emission Spectrometry

    Institute of Scientific and Technical Information of China (English)

    吴金龙; 金献忠

    2014-01-01

    A method was proposed for the determination of silicon, manganese, and phosphorus in pig iron with inductively coupled plasma atomic emission spectrometry . Samples were fused with sodium hydroxide and sodium peroxide in zirconium crucibles and leached out with hydrochloric acid solution. The matrix effect were investigated, no effect on the measured elements by sodium between 5.0 mg/mL and 6.0 mg/mL, zirconium in 20μg/mL and other elements in pig iron was found. Acidity effect was discussed and the effect of the volume of hydrochloric acid between 8 percent and 12 percent was able to be ignored. CRMs of pig iron were analyzed, and good agreements were achieved on the detected levels and the certified values with RSDs (n=5) being in the range of 0.3%-1.0%.%提出了一种电感耦合等离子体原子发射光谱法测定生铁中硅、锰、磷含量的方法。生铁样品采用氢氧化钠和过氧化钠在锆坩埚内熔融,盐酸浸取;研究了共存元素的影响,浓度在5.0 mg/mL-6.0 mg/mL之间的钠元素、20μg/mL的锆元素以及样品中其他共存元素对各元素的测定结果无影响;考察了酸度效应,盐酸用量在体积分数8%-12%时,对各元素测定的影响可以忽略。以生铁标准物质作为样品进行分析,测定值和认定值相吻合,RSD(n=5)为0.3%-1.0%。

  18. First Hard X-Ray Detection of the Non-Thermal Emission Around the Arches Cluster: Morphology and Spectral Studies With NuSTAR

    Science.gov (United States)

    Krivonos, Roman A.; Tomsick, John A.; Bauer, Franz E.; Baganoff, Frederick K.; Barriere, Nicolas M.; Bodaghee, Arash; Boggs, Steven E.; Christensen, Finn E.; Craig, William W.; Grefenstette, Brian W.; Hailey, Charles J.; Harrison, Fiona A.; Hong, JaeSub; Madsen, Kristin K.; Mori, Kaya; Nynka, Melania; Stern, Daniel; Zhang, William W.

    2014-01-01

    The Arches cluster is a young, densely packed massive star cluster in our Galaxy that shows a high level of star formation activity. The nature of the extended non-thermal X-ray emission around the cluster remains unclear. The observed bright Fe K(alpha) line emission at 6.4 keV from material that is neutral or in a low ionization state can be produced either by X-ray photoionization or by cosmic-ray particle bombardment or both. In this paper, we report on the first detection of the extended emission around the Arches cluster above 10 keV with the NuSTAR mission, and present results on its morphology and spectrum. The spatial distribution of the hard X-ray emission is found to be consistent with the broad region around the cluster where the 6.4 keV line is observed. The interpretation of the hard X-ray emission within the context of the X-ray reflection model puts a strong constraint on the luminosity of the possible illuminating hard X-ray source. The properties of the observed emission are also in broad agreement with the low-energy cosmic-ray proton excitation scenario. Key words: cosmic rays - Galaxy: center - ISM: general - X-rays: individual (Arches cluster)

  19. First hard X-ray detection of the non-thermal emission around the Arches cluster: morphology and spectral studies with NuSTAR

    CERN Document Server

    Krivonos, Roman A; Bauer, Franz E; Baganoff, Frederick K; Barriere, Nicolas M; Bodaghee, Arash; Boggs, Steven E; Christensen, Finn E; Craig, William W; Grefenstette, Brian W; Hailey, Charles J; Harrison, Fiona A; Hong, JaeSub; Madsen, Kristin K; Mori, Kaya; Nynka, Melania; Stern, Daniel; Zhang, William W

    2013-01-01

    The Arches cluster is a young, densely packed massive star cluster in our Galaxy that shows a high level of star formation activity. The nature of the extended non-thermal X-ray emission around the cluster remains unclear. The observed bright Fe K_alpha line emission at 6.4 keV from material that is neutral or in a low ionization state can be produced either by X-ray photoionization or by cosmic-ray particle bombardment or both. In this paper we report on the first detection of the extended emission around the Arches cluster above 10 keV with the NuSTAR mission, and present results on its morphology and spectrum. The spatial distribution of the hard X-ray emission is found to be consistent with the broad region around the cluster where the 6.4 keV line is observed. The interpretation of the hard X-ray emission within the context of the X-ray reflection model puts a strong constraint on the luminosity of the possible illuminating hard X-ray source. The properties of the observed emission are also in broad agre...

  20. 21 CFR 310.518 - Drug products containing iron or iron salts.

    Science.gov (United States)

    2010-04-01

    ... 21 Food and Drugs 5 2010-04-01 2010-04-01 false Drug products containing iron or iron salts. 310... Drug products containing iron or iron salts. Drug products containing elemental iron or iron salts as...) that contains iron or iron salts for use as an iron source shall bear the following statement:...

  1. From Iron Bowl to Iron Stomach

    Institute of Scientific and Technical Information of China (English)

    MICHAEL; L.; O’NEAL

    2009-01-01

    A few decades ago, "Iron Bowl" referred to not having to go hungry in China if you were employed by the Agovernment. The government gave you a job that secured the filling of one’s rice bowl. This concept and practice did create loyalty, as the times were hard. China has moved far past those times to become the

  2. Modeling the Anomalous Microwave Emission with Spinning Nanoparticles: No PAHs Required

    CERN Document Server

    Hensley, Brandon S

    2016-01-01

    In light of recent observational results indicating an apparent lack of correlation between the Anomalous Microwave Emission (AME) and mid-infrared emission from polycyclic aromatic hydrocarbons (PAHs), we assess whether rotational emission from spinning silicate and/or iron nanoparticles could account for the observed AME without violating observational constraints on interstellar abundances, ultraviolet extinction, and infrared emission. By modifying the SpDust code to compute the rotational emission from these grains, we find that nanosilicate grains could account for the entirety of the observed AME, whereas iron grains could be responsible for only a fraction, even for extreme assumptions on the amount of interstellar iron concentrated in ultrasmall iron nanoparticles. Given the added complexity of contributions from multiple grain populations to the total spinning dust emission, as well as existing uncertainties due to the poorly-constrained grain size, charge, and dipole moment distributions, we discus...

  3. Colour Metallography of Cast Iron

    Institute of Scientific and Technical Information of China (English)

    Zhou Jiyang; Liu Jincheng

    2009-01-01

    @@ This book consists of five sections:Chapter 1 Introduction,Chapter 2 Grey Iron,Chapter 3 Ductile Iron,Chapter 4Vermicular Cast Iron,and Chapter 5 White Cast Iron. CHINA FOUNDRY publishs this book in several parts serially,starting from the first issue of 2009.

  4. Colour Metallography of Cast Iron

    Institute of Scientific and Technical Information of China (English)

    Zhou Jiyang; Ph.D Liu Jincheng

    2010-01-01

    @@ Note: This book consists of five sections: Chapter 1 Introduction, Chapter 2 Grey Iron, Chapter 3 Spheroidal Graphite Cast Iron, Chapter 4 Vermicular Cast Iron, and Chapter 5 White Cast Iron. CHINA FOUNDRY publishes this book in several parts serially, starting from the first issue of 2009.

  5. Computational design of short pulse laser driven iron opacity experiments

    Science.gov (United States)

    Martin, M. E.; London, R. A.; Goluoglu, S.; Whitley, H. D.

    2017-02-01

    The resolution of current disagreements between solar parameters calculated from models and observations would benefit from the experimental validation of theoretical opacity models. Iron's complex ionic structure and large contribution to the opacity in the radiative zone of the sun make iron a good candidate for validation. Short pulse lasers can be used to heat buried layer targets to plasma conditions comparable to the radiative zone of the sun, and the frequency dependent opacity can be inferred from the target's measured x-ray emission. Target and laser parameters must be optimized to reach specific plasma conditions and meet x-ray emission requirements. The HYDRA radiation hydrodynamics code is used to investigate the effects of modifying laser irradiance and target dimensions on the plasma conditions, x-ray emission, and inferred opacity of iron and iron-magnesium buried layer targets. It was determined that plasma conditions are dominantly controlled by the laser energy and the tamper thickness. The accuracy of the inferred opacity is sensitive to tamper emission and optical depth effects. Experiments at conditions relevant to the radiative zone of the sun would investigate the validity of opacity theories important to resolving disagreements between solar parameters calculated from models and observations.

  6. Iron deficiency and iron deficiency anemia in women.

    Science.gov (United States)

    Coad, Jane; Pedley, Kevin

    2014-01-01

    Iron deficiency is one of the most common nutritional problems in the world and disproportionately affects women and children. Stages of iron deficiency can be characterized as mild deficiency where iron stores become depleted, marginal deficiency where the production of many iron-dependent proteins is compromised but hemoglobin levels are normal and iron deficiency anemia where synthesis of hemoglobin is decreased and oxygen transport to the tissues is reduced. Iron deficiency anemia is usually assessed by measuring hemoglobin levels but this approach lacks both specificity and sensitivity. Failure to identify and treat earlier stages of iron deficiency is concerning given the neurocognitive implications of iron deficiency without anemia. Most of the daily iron requirement is derived from recycling of senescent erythrocytes by macrophages; only 5-10 % comes from the diet. Iron absorption is affected by inhibitors and enhancers of iron absorption and by the physiological state. Inflammatory conditions, including obesity, can result in iron being retained in the enterocytes and macrophages causing hypoferremia as a strategic defense mechanism to restrict iron availability to pathogens. Premenopausal women usually have low iron status because of iron loss in menstrual blood. Conditions which further increase iron loss, compromise absorption or increase demand, such as frequent blood donation, gastrointestinal lesions, athletic activity and pregnancy, can exceed the capacity of the gastrointestinal tract to upregulate iron absorption. Women of reproductive age are at particularly high risk of iron deficiency and its consequences however there is a controversial argument that evolutionary pressures have resulted in an iron deficient phenotype which protects against infection.

  7. Colour Metallography of Cast Iron

    Institute of Scientific and Technical Information of China (English)

    Zhou Jiyang; Liu Jincheng

    2011-01-01

    @@ Vermicular graphite cast iron(VG iron for short in the following sections)is a type of cast iron in which the graphite is intermediate in shape between flake and spheroidal.Compared with the normal flake graphite in grey iron, the graphite in VG iron is shorter and thicker and shows a curved, more rounded shape.Because its outer contour is exactly like a worm, hence it is called vermicular graphite.

  8. Iron-Air Rechargeable Battery

    Science.gov (United States)

    Narayan, Sri R. (Inventor); Prakash, G.K. Surya (Inventor); Kindler, Andrew (Inventor)

    2014-01-01

    Embodiments include an iron-air rechargeable battery having a composite electrode including an iron electrode and a hydrogen electrode integrated therewith. An air electrode is spaced from the iron electrode and an electrolyte is provided in contact with the air electrode and the iron electrodes. Various additives and catalysts are disclosed with respect to the iron electrode, air electrode, and electrolyte for increasing battery efficiency and cycle life.

  9. Ocean iron fertilization

    Digital Repository Service at National Institute of Oceanography (India)

    Naqvi, S.W.A.; Smetacek, V.

    In 2009 and 2010, an Indo-German scientific expedition dusted the ocean with iron to stimulate the biological pump that captures atmosphereic carbon dioxide. Two onboard scientists tell the story of this controversial project. Besides raising...

  10. Iron-Deficiency Anemia

    Medline Plus

    Full Text Available ... Events Spokespeople Email Alerts E-Newsletters About NHLBI Organization NHLBI Director Budget, Planning, & Legislative Advisory Committees Jobs ... severity of the condition. Treatments may include dietary changes, medicines, and surgery. Severe iron-deficiency anemia may ...

  11. Iron-Deficiency Anemia

    Medline Plus

    Full Text Available ... of Intramural Research Research Resources Research Meeting Summaries Technology Transfer Clinical Trials What Are Clinical Trials? Children & ... of the condition. Treatments may include dietary changes, medicines, and surgery. Severe iron-deficiency anemia may require ...

  12. Iron-Deficiency Anemia

    Medline Plus

    Full Text Available ... CAUSES WHO IS AT RISK SIGNS & SYMPTOMS DIAGNOSIS TREATMENTS PREVENTION LIVING WITH CLINICAL TRIALS LINKS Related Topics ... Doctors usually can successfully treat iron-deficiency anemia. Treatment will depend on the cause and severity of ...

  13. Iron-Deficiency Anemia

    Medline Plus

    Full Text Available ... such as tiredness, poor skin tone, dizziness, and depression. After her doctor diagnosed her with iron-deficiency ... to stop her monthly periods. By following her treatment plan and making smart lifestyle choices, Susan continues ...

  14. Iron-Deficiency Anemia

    Medline Plus

    Full Text Available ... Deficiency Anemia What Is... CAUSES WHO IS AT RISK SIGNS & SYMPTOMS DIAGNOSIS TREATMENTS PREVENTION LIVING WITH CLINICAL ... and women are the two groups at highest risk for iron-deficiency anemia. Outlook Doctors usually can ...

  15. Iron-Deficiency Anemia

    Medline Plus

    Full Text Available ... chest pain, and other symptoms. Severe iron-deficiency anemia can lead to heart problems, infections, problems with growth and development in children, and other complications. Infants and young children and ...

  16. Iron-Deficiency Anemia

    Medline Plus

    Full Text Available ... Events Spokespeople Email Alerts E-Newsletters About NHLBI Organization NHLBI Director Budget, Planning, & Legislative Advisory Committees Jobs ... food. Overview Iron-deficiency anemia is a common type of anemia . The term "anemia" usually refers to ...

  17. Iron-Deficiency Anemia

    Medline Plus

    Full Text Available ... Deficiency Anemia Explore Iron-Deficiency Anemia What Is... CAUSES WHO IS AT RISK SIGNS & SYMPTOMS DIAGNOSIS TREATMENTS ... Google+ SITE INDEX ACCESSIBILITY PRIVACY STATEMENT FOIA NO FEAR ACT OIG CONTACT US National Institutes of Health ...

  18. Iron-Deficiency Anemia

    Medline Plus

    Full Text Available ... chest pain, and other symptoms. Severe iron-deficiency anemia can lead to heart problems, infections, problems with growth and development in children, and other complications. Infants and young children and ...

  19. Iron-Deficiency Anemia

    Medline Plus

    Full Text Available ... CAUSES WHO IS AT RISK SIGNS & SYMPTOMS DIAGNOSIS TREATMENTS PREVENTION LIVING WITH CLINICAL TRIALS LINKS Related Topics ... Doctors usually can successfully treat iron-deficiency anemia. Treatment will depend on the cause and severity of ...

  20. Iron-Deficiency Anemia

    Medline Plus

    Full Text Available ... a waste product) from your body. Anemia also can occur if your red blood cells don't ... have less hemoglobin than normal. Iron-deficiency anemia can cause fatigue (tiredness), shortness of breath, chest pain, ...

  1. Iron-Deficiency Anemia

    Medline Plus

    Full Text Available ... symptoms. Severe iron-deficiency anemia can lead to heart problems, infections, problems with growth and development in ... 18/2011 This video—presented by the National Heart, Lung, and Blood Institute, part of the National ...

  2. Iron-Deficiency Anemia

    Medline Plus

    Full Text Available ... of breath, chest pain, and other symptoms. Severe iron-deficiency anemia can lead to heart problems, infections, problems with growth and development in children, and other complications. Infants and young children and ...

  3. Iron and Your Child

    Science.gov (United States)

    ... red blood cell that carries oxygen from the lungs to the body. Iron gives hemoglobin the strength ... dried beans and peas dried fruits leafy dark green ... serving coffee or tea at mealtime — both contain tannins that reduce the ...

  4. Ferrous Sulfate (Iron)

    Science.gov (United States)

    Ferrous sulfate provides the iron needed by the body to produce red blood cells. It is used ... Ferrous sulfate comes as regular, coated, and extended-release (long-acting) tablets; regular and extended-release capsules; ...

  5. Iron isomaltoside 1000: a new intravenous iron for treating iron deficiency in chronic kidney disease

    DEFF Research Database (Denmark)

    Wikström, Björn; Bhandari, Sunil; Barany, Peter

    2011-01-01

    Patients with chronic kidney disease (CKD) often suffer from iron deficiency anemia necessitating treatment with intravenous iron. This study was designed to assess the safety of iron isomaltoside 1000 (Monofer) in CKD patients. The secondary objective was to assess its effect on iron deficiency...

  6. Microbes: Mini Iron Factories

    OpenAIRE

    Joshi, Kumar Batuk

    2014-01-01

    Microbes have flourished in extreme habitats since beginning of the Earth and have played an important role in geological processes like weathering, mineralization, diagenesis, mineral formation and destruction. Biotic mineralization is one of the most fascinating examples of how microbes have been influencing geological processes. Iron oxidizing and reducing bacteria are capable of precipitating wide varieties of iron oxides (magnetite), carbonates (siderite) and sulphides (greigite) via con...

  7. Iron-Refractory Iron Deficiency Anemia

    OpenAIRE

    Ebru Yılmaz Keskin; İdil Yenicesu

    2015-01-01

    Demir, oksijenin taşınması, DNA sentezi ve hücre çoğalması gibi çeşitli biyolojik reaksiyonlar için vazgeçilmez olduğundan, yaşam için zorunludur. Demir metabolizması ve bu elementin düzenlenmesiyle ilgili bilgilerimiz, son yıllarda belirgin şekilde değişmiştir. Demir metabolizması ile ilgili yeni bozukluklar tanımlanmış ve demirin başka bozuklukların kofaktörü olduğu anlaşılmaya başlamıştır. Hemokromatozis ve demir tedavisine dirençli demir eksikliği anemisi (IRIDA; “iron-refractory iron def...

  8. In Vitro Iron Availability from Insects and Sirloin Beef.

    Science.gov (United States)

    Latunde-Dada, Gladys O; Yang, Wenge; Vera Aviles, Mayra

    2016-11-09

    Interest in the consumption of insects (entomophagy) as an alternative environmentally sustainable source of protein in the diet of humans has recently witnessed a surge. Knowledge of the nutrient composition and, in particular, the bioavailability of minerals from insects is currently sparse. This study evaluated the availability of Fe, Ca, Cu, Mg, Mn, and Zn from four commonly eaten insects and compared these to sirloin beef. Soluble iron from the samples was measured by inductively coupled plasma optical emission spectrometry (ICP-OES). Iron bioavailability was determined using an in vitro simulated peptic-pancreatic digestion, followed by measurement of ferritin (a surrogate marker for iron absorption) in Caco-2 cells. Cricket and sirloin beef had comparably higher levels of Fe, Ca, and Mn than grasshopper, meal, and buffalo worms. However, iron solubility was significantly higher from the insect samples than from beef. The complementation of whole-wheat flour with insect or beef protein resulted in overall decreases in mineral content and iron solubility in the composite mixtures. Collectively, the data show that grasshopper, cricket, and mealworms contain significantly higher chemically available Ca, Cu, Mg, Mn, and Zn than sirloin. However, buffalo worms and sirloin exhibited higher iron bioavailability comparable to that of FeSO4. Commonly consumed insect species could be excellent sources of bioavailable iron and could provide the platform for an alternative strategy for increased mineral intake in the diets of humans.

  9. Intravenous Iron Sucrose for Children With Iron Deficiency Anemia.

    Science.gov (United States)

    Kaneva, Kristiyana; Chow, Erika; Rosenfield, Cathy G; Kelly, Michael J

    2017-07-01

    Iron deficiency anemia (IDA) is the most common nutritional deficiency in children. Most children with IDA are treated with oral iron preparations. However, intravenous (IV) iron is an alternative for children with severe IDA who have difficulty in adhering to or absorbing oral iron. We sought to describe the safety and effectiveness of IV iron sucrose for treatment of IDA in children. Pharmacy records of children who received IV iron sucrose at a children's hospital between 2004 and 2014 were reviewed. Laboratory markers of anemia and iron studies were obtained and preinfusion and postinfusion values were compared. Records were also reviewed for adverse reactions. A total of 142 patients received IV iron sucrose over 10 years. The mean age was 11 years, 9 months. One patient of 142 developed cough and wheezing during the infusion. No other adverse events were found. IV iron sucrose resulted in a statistically significant and clinically meaningful increase in hemoglobin, mean corpuscular volume, serum iron, ferritin, and % iron saturation, with a corresponding decrease in total iron binding capacity. The use of IV iron sucrose in pediatric patients with IDA is safe and leads to a moderate increase in hemoglobin and substantial improvement in iron studies.

  10. Oxidation Potentials in Iron and Steel Making

    Science.gov (United States)

    Matousek, J. W.

    2013-11-01

    The state of oxidation of a pyrometallurgical process given by the partial pressure of oxygen and the temperature (the oxidation potential) is one of the important properties monitored and controlled in the smelting and refining of iron and the nonferrous metals. Solid electrolyte sensors based on ZrO2 and a reference electrode such as Cr/Cr2O3 to measure the oxygen pressure found early application in the steel industry, followed soon after in copper, nickel, lead, and zinc smelting. Similar devices are installed in automobile postcombustion/exhaust trains as part of emission control systems. The current discussion reviews this technology as applied in the primary steps of iron and steel making and refining.

  11. Pressure-Induced Electronic Spin Transition of Iron in Magnesiow?stite-(Mg,Fe)O

    Energy Technology Data Exchange (ETDEWEB)

    Lin, J F; Gavriliuk, A G; Struzhkin, V V; Jacobsen, S D; Sturhahn, W; Hu, M Y; Chow, P; Yoo, C S

    2005-10-05

    An electronic transition of iron in magnesiowuestite has been studied with synchrotron Moessbauer and X-ray emission spectroscopies under high pressures. Synchrotron Moessbauer studies show that the quadrupole splitting disappears and the isomer shift drops significantly across the spin-paring transition of iron in (Mg{sub 0.75},Fe{sub 0.25})O between 62 and 70 GPa, whereas X-ray emission spectroscopy of the Fe-K{sub {beta}} fluorescence lines in dilute (Mg{sub 0.95},Fe{sub 0.05})O also confirms that a high-spin to low-spin transition occurs between 46 GPa and 55 GPa. Based upon current results and percolation theory, we reexamine the high-pressure phase diagram of (Mg,Fe)O and find that iron-iron exchange interaction plays an important role in stabilizing the high-spin state of iron in FeO-rich (Mg,Fe)O.

  12. Effect of mild iron overload on liver and kidney lipid peroxidation.

    Science.gov (United States)

    Galleano, M; Puntarulo, S

    1994-10-01

    1. Hepatotoxicity is the most common finding in patients with iron overload since the liver is the major recipient of iron excess, even though the kidney could be a target of iron toxicity. The effect of iron overload was studied in the early stages after iron-dextran injection in rats, as a model for secondary hemocromatosis. 2. Total hepatic and kidney iron content was markedly elevated over control values 20 h after the iron administration. Plasma GOT, GPT and LDH activities were not affected, suggesting that liver cell permeability was not affected by necrosis. 3. Spontaneous liver chemiluminescence was measured as an indicator of oxidative stress and lipid peroxidation. Light emission was increased four-fold 6 h after iron supplementation. 4. Increases in the generation of thiobarbituric acid reactive substances (TBARS in liver and kidney homogenates were detected after iron administration. 5. The activities of catalase, SOD and glutathione peroxidase were determined. Enzymatic activities declined in liver homogenates by 25, 36 and 32%, respectively, 20 h after iron injection. These activities were not affected in kidney as compared to control values, except for SOD activity that was decreased by 26%. 6. The content of alpha-tocopherol was decreased by 31% in whole kidney homogenates and by 40% in plasma. 7. Our data indicate that lipid peroxidation occurs after mild iron overload both in liver and kidney. Enzymatic antioxidants are consumed significantly in liver and alpha-tocopherol content decreases in kidney, suggesting an organ-specific antioxidant effect.

  13. Iron Absorption in Drosophila melanogaster

    Directory of Open Access Journals (Sweden)

    Fanis Missirlis

    2013-05-01

    Full Text Available The way in which Drosophila melanogaster acquires iron from the diet remains poorly understood despite iron absorption being of vital significance for larval growth. To describe the process of organismal iron absorption, consideration needs to be given to cellular iron import, storage, export and how intestinal epithelial cells sense and respond to iron availability. Here we review studies on the Divalent Metal Transporter-1 homolog Malvolio (iron import, the recent discovery that Multicopper Oxidase-1 has ferroxidase activity (iron export and the role of ferritin in the process of iron acquisition (iron storage. We also describe what is known about iron regulation in insect cells. We then draw upon knowledge from mammalian iron homeostasis to identify candidate genes in flies. Questions arise from the lack of conservation in Drosophila for key mammalian players, such as ferroportin, hepcidin and all the components of the hemochromatosis-related pathway. Drosophila and other insects also lack erythropoiesis. Thus, systemic iron regulation is likely to be conveyed by different signaling pathways and tissue requirements. The significance of regulating intestinal iron uptake is inferred from reports linking Drosophila developmental, immune, heat-shock and behavioral responses to iron sequestration.

  14. Iron Absorption in Drosophila melanogaster

    Science.gov (United States)

    Mandilaras, Konstantinos; Pathmanathan, Tharse; Missirlis, Fanis

    2013-01-01

    The way in which Drosophila melanogaster acquires iron from the diet remains poorly understood despite iron absorption being of vital significance for larval growth. To describe the process of organismal iron absorption, consideration needs to be given to cellular iron import, storage, export and how intestinal epithelial cells sense and respond to iron availability. Here we review studies on the Divalent Metal Transporter-1 homolog Malvolio (iron import), the recent discovery that Multicopper Oxidase-1 has ferroxidase activity (iron export) and the role of ferritin in the process of iron acquisition (iron storage). We also describe what is known about iron regulation in insect cells. We then draw upon knowledge from mammalian iron homeostasis to identify candidate genes in flies. Questions arise from the lack of conservation in Drosophila for key mammalian players, such as ferroportin, hepcidin and all the components of the hemochromatosis-related pathway. Drosophila and other insects also lack erythropoiesis. Thus, systemic iron regulation is likely to be conveyed by different signaling pathways and tissue requirements. The significance of regulating intestinal iron uptake is inferred from reports linking Drosophila developmental, immune, heat-shock and behavioral responses to iron sequestration. PMID:23686013

  15. X-ray emission from the nuclei, lobes and hot-gas environments of two FR-II radio galaxies

    CERN Document Server

    Croston, J H; Hardcastle, M J; Worrall, D M

    2004-01-01

    We report the detection of multiple components of X-ray emission from the two FR-II radio galaxies 3C 223 and 3C 284, based on new XMM-Newton observations. We attribute the detected X-ray emission from the lobes of both sources to inverse-Compton scattering of cosmic microwave background photons. With this model, we find that the magnetic field strength in the lobes is at the equipartition value for 3C 284, and within a factor of two of the equipartition value for 3C 223. We also detect group-scale hot atmospheres around both sources, and determine temperatures and pressures in the gas. The lobes of both sources are in pressure balance with the hot-gas environments, if the lobes contain only the synchrotron-emitting particles and the measured magnetic field strength. The core spectra of both sources contain an unabsorbed soft component, likely to be related to the radio jet, and an additional heavily absorbed power-law component. 3C 223 also displays a bright (EW ~ 500 eV) Fe K-alpha emission line.

  16. No Signatures of Black-Hole Spin in the X-ray Spectrum of the Seyfert 1 Galaxy Fairall 9

    CERN Document Server

    Yaqoob, Tahir; Tatum, Malachi M; Trevor, Max; Scholtes, Alexis

    2016-01-01

    Fairall 9 is one of several type 1 active galactic nuclei for which it has been claimed that the angular momentum (or spin) of the supermassive black hole can be robustly measured, using the Fe K$\\alpha$ emission line and Compton-reflection continuum in the X-ray spectrum. The method rests upon the interpretation of the Fe K$\\alpha$ line profile and associated Compton-reflection continuum in terms of relativistic broadening in the strong gravity regime in the innermost regions of an accretion disc, within a few gravitational radii of the black hole. Here, we re-examine a Suzaku X-ray spectrum of Fairall 9 and show that a face-on toroidal X-ray reprocessor model involving only nonrelativistic and mundane physics provides an excellent fit to the data. The Fe K$\\alpha$ line emission and Compton reflection continuum are calculated self-consistently, the iron abundance is solar, and an equatorial column density of $\\sim 10^{24} \\ \\rm cm^{-2}$ is inferred. In this scenario, neither the Fe K$\\alpha$ line, nor the Co...

  17. Acid monolayer functionalized iron oxide nanoparticle catalysts

    Science.gov (United States)

    Ikenberry, Myles

    Superparamagnetic iron oxide nanoparticle functionalization is an area of intensely active research, with applications across disciplines such as biomedical science and heterogeneous catalysis. This work demonstrates the functionalization of iron oxide nanoparticles with a quasi-monolayer of 11-sulfoundecanoic acid, 10-phosphono-1-decanesulfonic acid, and 11-aminoundecanoic acid. The carboxylic and phosphonic moieties form bonds to the iron oxide particle core, while the sulfonic acid groups face outward where they are available for catalysis. The particles were characterized by thermogravimetric analysis (TGA), transmission electron microscopy (TEM), potentiometric titration, diffuse reflectance infrared Fourier transform spectroscopy (DRIFTS), inductively coupled plasma optical emission spectrometry (ICP-OES), X-ray photoelectron spectrometry (XPS), and dynamic light scattering (DLS). The sulfonic acid functionalized particles were used to catalyze the hydrolysis of sucrose at 80° and starch at 130°, showing a higher activity per acid site than the traditional solid acid catalyst Amberlyst-15, and comparing well against results reported in the literature for sulfonic acid functionalized mesoporous silicas. In sucrose catalysis reactions, the phosphonic-sulfonic nanoparticles (PSNPs) were seen to be incompletely recovered by an external magnetic field, while the carboxylic-sulfonic nanoparticles (CSNPs) showed a trend of increasing activity over the first four recycle runs. Between the two sulfonic ligands, the phosphonates produced a more tightly packed monolayer, which corresponded to a higher sulfonic acid loading, lower agglomeration, lower recoverability through application of an external magnetic field, and higher activity per acid site for the hydrolysis of starch. Functionalizations with 11-aminoundecanoic acid resulted in some amine groups binding to the surfaces of iron oxide nanoparticles. This amine binding is commonly ignored in iron oxide

  18. Suspension Hydrogen Reduction of Iron Oxide Concentrates

    Energy Technology Data Exchange (ETDEWEB)

    H.Y. Sohn

    2008-03-31

    The objective of the project is to develop a new ironmaking technology based on hydrogen and fine iron oxide concentrates in a suspension reduction process. The ultimate objective of the new technology is to replace the blast furnace and to drastically reduce CO2 emissions in the steel industry. The goals of this phase of development are; the performance of detailed material and energy balances, thermochemical and equilibrium calculations for sulfur and phosphorus impurities, the determination of the complete kinetics of hydrogen reduction and bench-scale testing of the suspension reduction process using a large laboratory flash reactor.

  19. Suspension Hydrogen Reduction of Iron Oxide Concentrates

    Energy Technology Data Exchange (ETDEWEB)

    H.Y. Sohn

    2008-03-31

    The objective of the project is to develop a new ironmaking technology based on hydrogen and fine iron oxide concentrates in a suspension reduction process. The ultimate objective of the new technology is to replace the blast furnace and to drastically reduce CO2 emissions in the steel industry. The goals of this phase of development are; the performance of detailed material and energy balances, thermochemical and equilibrium calculations for sulfur and phosphorus impurities, the determination of the complete kinetics of hydrogen reduction and bench-scale testing of the suspension reduction process using a large laboratory flash reactor.

  20. Iron replacement therapy

    DEFF Research Database (Denmark)

    Nielsen, Ole Haagen; Coskun, Mehmet; Weiss, Günter

    2016-01-01

    PURPOSE OF REVIEW: Approximately, one-third of the world's population suffers from anemia, and at least half of these cases are because of iron deficiency. With the introduction of new intravenous iron preparations over the last decade, uncertainty has arisen when these compounds should be admini...... treatment, when to follow-up for relapse, which dosage and type of therapy should be recommended or not recommended, and if some patients should not be treated....... be administered and under which circumstances oral therapy is still an appropriate and effective treatment. RECENT FINDINGS: Numerous guidelines are available, but none go into detail about therapeutic start and end points or how iron-deficiency anemia should be best treated depending on the underlying cause...... of iron deficiency or in regard to concomitant underlying or additional diseases. SUMMARY: The study points to major issues to be considered in revisions of future guidelines for the true optimal iron replacement therapy, including how to assess the need for treatment, when to start and when to stop...

  1. [Iron deficiency and iron deficiency anemia are global health problems].

    Science.gov (United States)

    Dahlerup, Jens; Lindgren, Stefan; Moum, Björn

    2015-03-10

    Iron deficiency and iron deficiency anemia are global health problems leading to deterioration in patients' quality of life and more serious prognosis in patients with chronic diseases. The cause of iron deficiency and anemia is usually a combination of increased loss and decreased intestinal absorption and delivery from iron stores due to inflammation. Oral iron is first line treatment, but often hampered by intolerance. Intravenous iron is safe, and the preferred treatment in patients with chronic inflammation and bowel diseases. The goal of treatment is normalisation of hemoglobin concentration and recovery of iron stores. It is important to follow up treatment to ensure that these objectives are met and also long-term in patients with chronic iron loss and/or inflammation to avoid recurrence of anemia.

  2. A randomized trial of iron isomaltoside versus iron sucrose in patients with iron deficiency anemia.

    Science.gov (United States)

    Derman, Richard; Roman, Eloy; Modiano, Manuel R; Achebe, Maureen M; Thomsen, Lars L; Auerbach, Michael

    2017-03-01

    Iron deficiency anemia (IDA) is common in many chronic diseases, and intravenous (IV) iron offers a rapid and efficient iron correction. This trial compared the efficacy and safety of iron isomaltoside and iron sucrose in patients with IDA who were intolerant of, or unresponsive to, oral iron. The trial was an open-label, comparative, multi-center trial. Five hundred and eleven patients with IDA from different causes were randomized 2:1 to iron isomaltoside or iron sucrose and followed for 5 weeks. The cumulative dose of iron isomaltoside was based on body weight and hemoglobin (Hb), administered as either a 1000 mg infusion over more than 15 minutes or 500 mg injection over 2 minutes. The cumulative dose of iron sucrose was calculated according to Ganzoni and administered as repeated 200 mg infusions over 30 minutes. The mean cumulative dose of iron isomaltoside was 1640.2 (standard deviation (SD): 357.6) mg and of iron sucrose 1127.9 (SD: 343.3) mg. The primary endpoint was the proportion of patients with a Hb increase ≥2 g/dL from baseline at any time between weeks 1-5. Both non-inferiority and superiority were confirmed for the primary endpoint, and a shorter time to Hb increase ≥2 g/dL was observed with iron isomaltoside. For all biochemical efficacy parameters, faster and/or greater improvements were found with iron isomaltoside. Both treatments were well tolerated; 0.6% experienced a serious adverse drug reaction. Iron isomaltoside was more effective than iron sucrose in achieving a rapid improvement in Hb. Furthermore, iron isomaltoside has an advantage over iron sucrose in allowing higher cumulative dosing in fewer administrations. Both treatments were well tolerated in a broad population with IDA.

  3. The structure and bonding of iron-acceptor pairs in silicon

    Energy Technology Data Exchange (ETDEWEB)

    Zhao, S.; Assali, L.V.C.; Kimerling, L.C. [Massachusetts Inst. of Technology, Cambridge, MA (United States)

    1995-08-01

    The highly mobile interstitial iron and Group III impurities (B, Al, Ga, In) form iron-acceptor pairs in silicon. Based on the migration kinetics and taking host silicon as a dielectric medium, we have simulated the pairing process in a static silicon lattice. Different from the conventional point charge ionic model, our phenomenological calculations include (1) a correction that takes into account valence electron cloud polarization which adds a short range, attractive interaction in the iron-acceptor pair bonding; and (2) silicon lattice relaxation due to the atomic size difference which causes a local strain field. Our model explains qualitatively (1) trends among the iron-acceptor pairs revealing an increase of the electronic state hole emission energy with increasing principal quantum number of acceptor and decreasing pair separation distance; and (2) the stable and metastable sites and configurational symmetries of the iron-acceptor pairs. The iron-acceptor pairing and bonding mechanism is also discussed.

  4. Iron deficiency and cognitive functions

    Directory of Open Access Journals (Sweden)

    Jáuregui-Lobera I

    2014-11-01

    Full Text Available Ignacio Jáuregui-Lobera Department of Nutrition and Bromatology, Pablo de Olavide University, Seville, Spain Abstract: Micronutrient deficiencies, especially those related to iodine and iron, are linked to different cognitive impairments, as well as to potential long-term behavioral changes. Among the cognitive impairments caused by iron deficiency, those referring to attention span, intelligence, and sensory perception functions are mainly cited, as well as those associated with emotions and behavior, often directly related to the presence of iron deficiency anemia. In addition, iron deficiency without anemia may cause cognitive disturbances. At present, the prevalence of iron deficiency and iron deficiency anemia is 2%–6% among European children. Given the importance of iron deficiency relative to proper cognitive development and the alterations that can persist through adulthood as a result of this deficiency, the objective of this study was to review the current state of knowledge about this health problem. The relevance of iron deficiency and iron deficiency anemia, the distinction between the cognitive consequences of iron deficiency and those affecting specifically cognitive development, and the debate about the utility of iron supplements are the most relevant and controversial topics. Despite there being methodological differences among studies, there is some evidence that iron supplementation improves cognitive functions. Nevertheless, this must be confirmed by means of adequate follow-up studies among different groups. Keywords: iron deficiency, anemia, cognitive functions, supplementation

  5. How Is Iron-Deficiency Anemia Treated?

    Science.gov (United States)

    ... the NHLBI on Twitter. How Is Iron-Deficiency Anemia Treated? Treatment for iron-deficiency anemia will depend ... may be advised. Treatments for Severe Iron-Deficiency Anemia Blood Transfusion If your iron-deficiency anemia is ...

  6. Iron prophylaxis during pregnancy -- how much iron is needed? A randomized dose- response study of 20-80 mg ferrous iron daily in pregnant women

    DEFF Research Database (Denmark)

    Milman, Nils; Bergholt, Thomas; Eriksen, Lisbeth

    2005-01-01

    To determine the lowest dose of iron preventative of iron deficiency and iron deficiency anemia in pregnancy.......To determine the lowest dose of iron preventative of iron deficiency and iron deficiency anemia in pregnancy....

  7. Prediction of reducible soil iron content from iron extraction data

    NARCIS (Netherlands)

    Bodegom, van P.M.; Reeven, van J.; Denier van der Gon, H.A.C.

    2003-01-01

    Soils contain various iron compounds that differ in solubility, reducibility and extractability. Moreover, the contribution of the various iron compounds to total iron (Fe) and total Fe concentrations differs highly among soils. As a result, the total reducible Fe content can also differ among

  8. Iron deficiency anemia in children.

    Science.gov (United States)

    Subramaniam, Girish; Girish, Meenakshi

    2015-06-01

    Iron deficiency is not just anemia; it can be responsible for a long list of other manifestations. This topic is of great importance, especially in infancy and early childhood, for a variety of reasons. Firstly, iron need is maximum in this period. Secondly, diet in infancy is usually deficient in iron. Thirdly and most importantly, iron deficiency at this age can result in neurodevelopmental and cognitive deficits, which may not be reversible. Hypochromia and microcytosis in a complete blood count (CBC) makes iron deficiency anemia (IDA) most likely diagnosis. Absence of response to iron should make us look for other differential diagnosis like β thalassemia trait and anemia of chronic disease. Celiac disease is the most important cause of true IDA not responding to oral iron therapy. While oral ferrous sulphate is the cheapest and most effective therapy for IDA, simple nonpharmacological and pharmacological measures can go a long way in prevention of iron deficiency.

  9. Oral iron chelators.

    Science.gov (United States)

    Kwiatkowski, Janet L

    2010-02-01

    Effective chelation therapy can prevent or reverse organ toxicity related to iron overload, yet cardiac complications and premature death continue to occur, largely related to difficulties with compliance in patients who receive parenteral therapy. The use of oral chelators may be able to overcome these difficulties and improve patient outcomes. A chelator's efficacy at cardiac and liver iron removal and side-effect profile should be considered when tailoring individual chelation regimens. Broader options for chelation therapy, including possible combination therapy, should improve clinical efficacy and enhance patient care.

  10. Theoretical modelling of the AGN iron-line/continuum time-lags in the lamp-post geometry

    CERN Document Server

    Epitropakis, A; Dovčiak, M; Pecháček, Tomáš; Emmanoulopoulos, D; Karas, V; McHardy, I M

    2016-01-01

    Context: Theoretical modelling of time-lags between variations in the Fe K$\\alpha$ emission and the X-ray continuum has the potential of shedding light on the physics and geometry of the X-ray emitting region in active galaxies (AGN) and X-ray binaries. In this work, we present the results from a systematic analysis of time-lags between variations in two energy bands ($5-7$ versus $2-4\\,\\mathrm{keV}$) for seven X-ray bright and variable AGN. Aims: To estimate time-lags as accurately as possible, and fit them with theoretical models, in the context of the `lamp-post' geometry, to constrain the geometry of the X-ray emitting region in AGN. Methods: We used all available archival \\textit{XMM-Newton} data for the sources in our sample and extracted light curves in the $5-7$ and $2-4\\,\\mathrm{keV}$ energy bands. We used these light curves and applied a thoroughly tested (through extensive numerical simulations) recipe in order to estimate time-lags which have minimal bias, approximately follow a Gaussian distribut...

  11. Hepcidin Suppresses Brain Iron Accumulation by Downregulating Iron Transport Proteins in Iron-Overloaded Rats.

    Science.gov (United States)

    Du, Fang; Qian, Zhong-Ming; Luo, Qianqian; Yung, Wing-Ho; Ke, Ya

    2015-08-01

    Iron accumulates progressively in the brain with age, and iron-induced oxidative stress has been considered as one of the initial causes for Alzheimer's disease (AD) and Parkinson's disease (PD). Based on the role of hepcidin in peripheral organs and its expression in the brain, we hypothesized that this peptide has a role to reduce iron in the brain and hence has the potential to prevent or delay brain iron accumulation in iron-associated neurodegenerative disorders. Here, we investigated the effects of hepcidin expression adenovirus (ad-hepcidin) and hepcidin peptide on brain iron contents, iron transport across the brain-blood barrier, iron uptake and release, and also the expression of transferrin receptor-1 (TfR1), divalent metal transporter 1 (DMT1), and ferroportin 1 (Fpn1) in cultured microvascular endothelial cells and neurons. We demonstrated that hepcidin significantly reduced brain iron in iron-overloaded rats and suppressed transport of transferrin-bound iron (Tf-Fe) from the periphery into the brain. Also, the peptide significantly inhibited expression of TfR1, DMT1, and Fpn1 as well as reduced Tf-Fe and non-transferrin-bound iron uptake and iron release in cultured microvascular endothelial cells and neurons, while downregulation of hepcidin with hepcidin siRNA retrovirus generated opposite results. We concluded that, under iron-overload, hepcidin functions to reduce iron in the brain by downregulating iron transport proteins. Upregulation of brain hepcidin by ad-hepcidin emerges as a new pharmacological treatment and prevention for iron-associated neurodegenerative disorders.

  12. Colour Metallography of Cast Iron

    Institute of Scientific and Technical Information of China (English)

    Zhou Jiyang

    2009-01-01

    @@ Grey Iron(Ⅲ) 2.5 Crystallization of the LTF during final stage of eutectic solidification of grey iron In the final stage of eutectic solidification, eutectic cells grow gradually into large sizes; the liquid iron between the cells enters the last stage of solidification. At this time, the region of the remaining liquid iron is called last to freeze volume, LTF in short, as shown in Fig.2-39.

  13. FISICA Integral Field Spectroscopy of the Shocked Iron Gas in the Supernova Remnant G11.2--0.3

    Science.gov (United States)

    Moon, Dae-Sik; Eikenberry, Stephen S.; Koo, Bon-Chul; Raines, S. Nicholas; Gruel, Nicolas

    2006-02-01

    We have recently discovered strong iron line ([Fe II] (lambda)1.644 (mu)m) emission in the young supernova remnant G11.2-0.3. The iron line emission occurs at the south-eastern shell edge of G11.2-0.3, and positionally overlaps with the very strong X-ray and radio emission of the supernova remnant. The iron line emission is most likely caused by the shock acceleration of G11.2-0.3 interacting with the ambient medium. We propose to carry out JH-band integral-field spectroscopy of the two iron line clumps in G11.2-0.3 with FISICA, an image-slicing integral-field unit for FLAMINGOS, which will give us a uniquely comprehensive view of the strong shock acceleration of a SNR.

  14. Elevated levels of iron in groundwater in Prey Veng province in Cambodia: a possible factor contributing to high iron stores in women.

    Science.gov (United States)

    Karakochuk, Crystal D; Murphy, Heather M; Whitfield, Kyly C; Barr, Susan I; Vercauteren, Suzanne M; Talukder, Aminuzzaman; Porter, Keith; Kroeun, Hou; Eath, Many; McLean, Judy; Green, Timothy J

    2015-06-01

    Iron is a natural element found in food, water and soil and is essential for human health. Our aim was to determine the levels of iron and 25 other metals and trace elements in groundwater from 22 households in Prey Veng, Cambodia. Water analyses were conducted using inductively coupled plasma-mass spectrometry and optical emission spectrometry. Compared to the 2011 World Health Organization guidelines for drinking water quality, aluminum, iron and manganese exceeded maximum levels (in 4.5, 72.7 and 40.9% of samples, respectively). Compared to the 2004 Cambodian drinking water quality standards, iron and manganese exceeded maximum levels (in 59.1 and 36.4% of samples, respectively). We found no evidence of arsenic contamination. Guidelines for iron were established primarily for esthetic reasons (e.g. taste), whereas other metals and elements have adverse effects associated with toxicity. Iron in groundwater ranged from 134 to 5,200 μg/L (mean ∼1,422 μg/L). Based on a daily consumption of 3 L groundwater, this equates to ∼0.4-15.6 mg iron (mean ∼4.3 mg/day), which may be contributing to high iron stores and the low prevalence of iron deficiency anemia in Prey Veng women. Elevated levels of manganese in groundwater are a concern and warrant further investigation.

  15. Absorption and Turnover Rates of Iron Measured by the Whole Body Counter

    Energy Technology Data Exchange (ETDEWEB)

    Price, D. C.; Cohn, S. H.

    1962-09-05

    Human iron metabolism has been extensively studied in the past twenty-five years with the radioisotopes iron55 and iron59. Before the availability of the whole body counter, however, iron absorption studies were performed by the indirect methods of fecal assay of unabsorbed radioiron, and estimation of red cell incorporation of absorbed tracer. The few long-term excretion studies performed required numerous assumptions, since human iron excretion was less well understood. Whole body counting provides a simple and accurate method of measuring the total body retention of administrative tracer iron59, thus making absorption and subsequent excretion determinations possible with a single radioiron study. The energetic gamma emissions of iron59 permit ready external detection with small quantities of isotope, Normal radioiron distribution is uniform throughout the circulating red cell mass and thus minimize geometry influences on the counting efficiency, 0nly the 45.1 day half-life of iron59 limits long term iron turnover studies. Measurements of iron59 absorption and long-term body turnover have been under way at Brookhaven National Laboratory for over two years. The present paper outlines some of the results of these studies, and discusses some implications of the method. (auth)

  16. Phytases for improved iron absorption

    DEFF Research Database (Denmark)

    Nielsen, Anne Veller Friis; Meyer, Anne S.

    2016-01-01

    Phytase enzymes present an alternative to iron supplements, because they have been shown to improve iron absorption by means of catalysing the degradation of a potent iron absorption inhibitor: phytic acid. Phytic acid is a hexaphosphate of inositol and is particularly prevalent in cereal grains...

  17. Iron deficiency anemia in children

    OpenAIRE

    Pochinok, T. V.

    2016-01-01

    In the article the role of iron in the human body is highlighted. The mechanism of development of iron deficiency states, their consequences and the basic principles of diagnosis and correction of children of different ages are shown.Key words: children, iron deficiency anemia, treatment.

  18. Iron deficiency and cardiovascular disease

    NARCIS (Netherlands)

    von Haehling, Stephan; Jankowska, Ewa A.; van Veldhuisen, Dirk J.; Ponikowski, Piotr; Anker, Stefan D.

    2015-01-01

    Iron deficiency affects up to one-third of the world's population, and is particularly common in elderly individuals and those with certain chronic diseases. Iron excess can be detrimental in cardiovascular illness, and research has now also brought anaemia and iron deficiency into the focus of card

  19. Energy conservation and emissions reduction strategies in foundry industry

    Directory of Open Access Journals (Sweden)

    Li Yuanyuan

    2010-11-01

    Full Text Available Current energy conservation and emissions reduction strategies in iron and steel industry were reviewed. Since foundry industry is one of the major source of energy consumption and pollution emission (especially CO2, issues concerning energy-saving and emission-reduction have been raised by governments and the industry. Specialists from around the world carried out multidimensional analyses and evaluation on the potentials in energy conservation and emissions reduction in iron and steel industry, and proposed various kinds of analyzing models. The primary measures mainly focus on the targeted policies formulation and also on clean and high-efficient technologies development. The differences and similarities in energy conservation and emission reduction in foundry industry between China and other countries were discussed, while, the future development trend was also pointed out.

  20. Extracting phosphoric iron under laboratorial conditions smelting bog iron ores

    Science.gov (United States)

    Török, B.; Thiele, A.

    2013-12-01

    In recent years it has been indicated by archaeometric investigations that phosphoric-iron (P-iron, low carbon steel with 0,5-1,5wt% P), which is an unknown and unused kind of steel in the modern industry, was widely used in different parts of the world in medieval times. In this study we try to explore the role of phosphorus in the arhaeometallurgy of iron and answer some questions regarding the smelting bog iron ores with high P-content. XRF analyses were performed on bog iron ores collected in Somogy county. Smelting experiments were carried out on bog iron ores using a laboratory model built on the basis of previously conducted reconstructed smelting experiments in copies of excavated furnaces. The effect of technological parameters on P-content of the resulted iron bloom was studied. OM and SEM-EDS analyses were carried out on the extracted iron and slag samples. On the basis of the material analyses it can be stated that P-iron is usually extracted but the P-content is highly affected by technological parameters. Typical microstructures of P-iron and of slag could also be identified. It could also be established that arsenic usually solved in high content in iron as well.

  1. Iron dominated magnets

    Energy Technology Data Exchange (ETDEWEB)

    Fischer, G.E.

    1985-07-01

    These two lectures on iron dominated magnets are meant for the student of accelerator science and contain general treatments of the subjects design and construction. The material is arranged in the categories: General Concepts and Cost Considerations, Profile Configuration and Harmonics, Magnetic Measurements, a few examples of ''special magnets'' and Materials and Practices. Extensive literature is provided.

  2. State of the iron

    DEFF Research Database (Denmark)

    Reinisch, Walter; Staun, Michael; Bhandari, Sunil

    2013-01-01

    Iron deficiency anemia (IDA) frequently occurs in patients suffering from inflammatory bowel disease (IBD) and negatively impacts their quality of life. Nevertheless, the condition appears to be both under-diagnosed and undertreated. Regular biochemical screening of patients with IBD for anemia...

  3. Development of iron aluminides

    Energy Technology Data Exchange (ETDEWEB)

    Viswanathan, S.; Sikka, V.K.; Andleigh, V.K. [and others

    1995-06-01

    The primary reason for the poor room-temperature ductility of Fe{sub 3}Al-based alloys is generally accepted to be environmental embrittlement due to hydrogen produced by the reaction of aluminum with water vapor present in the test atmosphere. In the as-cast condition, another possible reason for the low room-temperature ductility is the large grain size (0.5 to 3 mm) of the cast material. While recent studies on iron aluminides in the wrought condition have led to higher room-temperature ductility and increased high-temperature strength, limited studies have been conducted on iron aluminides in the as-cast condition. The purpose of this study was to induce grain refinement of the as-cast alloy through alloying additions to the melt and study the effect on room-temperature ductility as measured by the strain corresponding to the maximum stress obtained in a three-point bend test. A base charge of Fe-28% Al-5% Cr alloy was used; as in previous studies this ternary alloy exhibited the highest tensile ductility of several alloys tested. Iron aluminide alloys are being considered for many structural uses, especially for applications where their excellent corrosion resistance is needed. Several alloy compositions developed at ORNL have been licensed to commercial vendors for development of scale-up procedures. With the licensees and other vendors, several applications for iron aluminides are being pursued.

  4. The New Iron Man

    Institute of Scientific and Technical Information of China (English)

    2008-01-01

    Sinosteel wins a hard-fought victory in the marathon battle for Australia’s Midwest Sinosteel Corp.,one of China’s larg- est steelmakers,has finally clinched its AU$1.36 billion($1.31 billion) takeover of Midwest Corp.,a Perth (Australia)-based iron ore miner,after a

  5. Nutritional iron deficiency: the role of oral iron supplementation.

    Science.gov (United States)

    Lachowicz, J I; Nurchi, V M; Fanni, D; Gerosa, C; Peana, M; Zoroddu, M A

    2014-01-01

    Nutritional iron deficiency represents a relevant health problem mainly in developing countries. Children and pregnant women represent the main target of this disease, and the low amount of bio-available iron mostly depends on plant-based diets. Iron deficiency may have serious consequences, with severe impairment of the immune function leading to infectious diseases. The brain development in embryos and fetuses during gestation can be greatly affected by iron deficiency of the mother with heavy outcomes on the cognition status of children. A better understanding of molecular pathways involved in iron absorption and metabolism are the basis for new strategies for developing a therapy for iron deficiency. Different therapeutic strategies are summarized, and iron fortification appears the best tool.

  6. New insights into iron deficiency and iron deficiency anemia.

    Science.gov (United States)

    Camaschella, Clara

    2017-02-13

    Recent advances in iron metabolism have stimulated new interest in iron deficiency (ID) and its anemia (IDA), common conditions worldwide. Absolute ID/IDA, i.e. the decrease of total body iron, is easily diagnosed based on decreased levels of serum ferritin and transferrin saturation. Relative lack of iron in specific organs/tissues, and IDA in the context of inflammatory disorders, are diagnosed based on arbitrary cut offs of ferritin and transferrin saturation and/or marker combination (as the soluble transferrin receptor/ferritin index) in an appropriate clinical context. Most ID patients are candidate to traditional treatment with oral iron salts, while high hepcidin levels block their absorption in inflammatory disorders. New iron preparations and new treatment modalities are available: high-dose intravenous iron compounds are becoming popular and indications to their use are increasing, although long-term side effects remain to be evaluated.

  7. 49 CFR 192.373 - Service lines: Cast iron and ductile iron.

    Science.gov (United States)

    2010-10-01

    ... 49 Transportation 3 2010-10-01 2010-10-01 false Service lines: Cast iron and ductile iron. 192.373... Regulators, and Service Lines § 192.373 Service lines: Cast iron and ductile iron. (a) Cast or ductile iron... cast iron pipe or ductile iron pipe is installed for use as a service line, the part of the...

  8. Iron-fortified milk can improve iron status in young women with low iron stores

    NARCIS (Netherlands)

    Scholz-Ahrens, K.E.; Schaafsma, G.; Kip, P.; Elbers, F.; Boeing, H.; Schrezenmeir, J.

    2004-01-01

    A considerable proportion of the populations of developing and industrialised nations does not meet the recommended daily allowance for iron and are thus at risk of chronic iron-deficiency anaemia. In a placebo-controlled, double-blind study we investigated whether supplementation with iron-enriched

  9. Iron-fortified milk can improve iron status in young women with low iron stores

    NARCIS (Netherlands)

    Scholz-Ahrens, K.E.; Schaafsma, G.; Kip, P.; Elbers, F.; Boeing, H.; Schrezenmeir, J.

    2004-01-01

    A considerable proportion of the populations of developing and industrialised nations does not meet the recommended daily allowance for iron and are thus at risk of chronic iron-deficiency anaemia. In a placebo-controlled, double-blind study we investigated whether supplementation with iron-enriched

  10. [Iron deficiency, thrombocytosis and thromboembolism].

    Science.gov (United States)

    Evstatiev, Rayko

    2016-10-01

    Iron deficiency, the most common nutritional deficiency worldwide, is often associated with reactive thrombocytosis. Although secondary thrombocytosis is commonly considered to be harmless, there is accumulating evidence that elevated platelet counts, especially in the setting of iron deficiency, can lead to an increased thromboembolic risk in both arterial and venous systems. Here we present the mechanisms of iron deficiency-induced thrombocytosis and summarize its clinical consequences especially in patients with inflammatory bowel diseases, chronic kidney disease or cancer. We hypothesize that iron deficiency is an underestimated thromboembolic risk factor, and that iron replacement therapy can become an effective preventive strategy in a variety of clinical settings.

  11. Iron and ferritin accumulate in separate cellular locations in Phaseolus seeds

    Directory of Open Access Journals (Sweden)

    Blair Matthew W

    2010-02-01

    Full Text Available Abstract Background Iron is an important micronutrient for all living organisms. Almost 25% of the world population is affected by iron deficiency, a leading cause of anemia. In plants, iron deficiency leads to chlorosis and reduced yield. Both animals and plants may suffer from iron deficiency when their diet or environment lacks bioavailable iron. A sustainable way to reduce iron malnutrition in humans is to develop staple crops with increased content of bioavailable iron. Knowledge of where and how iron accumulates in seeds of crop plants will increase the understanding of plant iron metabolism and will assist in the production of staples with increased bioavailable iron. Results Here we reveal the distribution of iron in seeds of three Phaseolus species including thirteen genotypes of P. vulgaris, P. coccineus, and P. lunatus. We showed that high concentrations of iron accumulate in cells surrounding the provascular tissue of P. vulgaris and P. coccineus seeds. Using the Perls' Prussian blue method, we were able to detect iron in the cytoplasm of epidermal cells, cells near the epidermis, and cells surrounding the provascular tissue. In contrast, the protein ferritin that has been suggested as the major iron storage protein in legumes was only detected in the amyloplasts of the seed embryo. Using the non-destructive micro-PIXE (Particle Induced X-ray Emission technique we show that the tissue in the proximity of the provascular bundles holds up to 500 μg g-1 of iron, depending on the genotype. In contrast to P. vulgaris and P. coccineus, we did not observe iron accumulation in the cells surrounding the provascular tissues of P. lunatus cotyledons. A novel iron-rich genotype, NUA35, with a high concentration of iron both in the seed coat and cotyledons was bred from a cross between an Andean and a Mesoamerican genotype. Conclusions The presented results emphasize the importance of complementing research in model organisms with analysis in

  12. Response of acid mobilization of iron-containing mineral dust to improvement of air quality projected in the future

    Directory of Open Access Journals (Sweden)

    A. Ito

    2013-10-01

    Full Text Available Acidification of dust aerosols may increase aerosol iron (Fe solubility, which is linked to mineral properties. Combustion aerosols can also elevate aerosol iron solubility when aerosol loading is low. Here, we use an atmospheric chemical transport model to investigate the deposition of filterable iron and its response to changes in anthropogenic emissions of both combustion aerosols and precursor gases. By introducing three classes of iron-containing minerals into the detailed aerosol chemistry model, we provide a theoretical examination of the effects of different dissolution behaviors on the acid mobilization of iron. Comparisons of modeled Fe dissolution curves with the measured dissolution rates for African (Tibesti and Asian (Beijing dust samples show overall good agreement under acidic conditions. The improved treatment of Fe in mineral dust and its dissolution scheme results in reasonable predictive capability for iron solubility over the oceans in the Northern Hemisphere. Our model results suggest that the improvement of air quality projected in the future will lead to a decrease of the filterable iron deposition from iron-containing mineral dust to the northeastern Pacific due to less acidification in Asian dust, which is mainly associated with the reduction of nitrogen oxides (NOx emissions. These results could have important implications for iron fertilization of phytoplankton growth, and highlight the necessity of improving the process-based quantitative understanding of the response of the chemical modification in iron-containing minerals to environmental changes.

  13. Radio and X-ray emission from disc winds in radio-quiet quasars

    CERN Document Server

    Steenbrugge, K C; Kuncic, Z; Blundell, K M

    2010-01-01

    It has been proposed that the radio spectra of radio-quiet quasars is produced by free-free emission in the optically thin part of an accretion disc wind. An important observational constraint on this model is the observed X-ray luminosity. We investigate this constraint using a sample of PG radio-quiet quasars for which XMM-Newton EPIC spectra are available. Comparing the predicted and measured luminosities for 0.5, 2 and 5 keV, we conclude that all of the studied PG quasars require a large hydrogen column density absorber, requiring these quasars to be close to or Compton-thick. Such a large column density can be directly excluded for PG 0050+124, for which a high-resolution RGS spectrum exists. Further constraint on the column density for a further 19 out of the 21 studied PG quasars comes from the EPIC spectrum characteristics such as hard X-ray power-law photon index and the equivalent width of the Fe Kalpha line; and the small equivalent width of the C IV absorber present in UV spectra. For 2 sources: P...

  14. Spectral Modeling of the Charge-Exchange X-ray Emission from M82

    CERN Document Server

    Zhang, Shuinai; Ji, Li; Smith, Randall K; Foster, Adam R; Zhou, Xin

    2014-01-01

    It has been proposed that the charge exchange (CX) process at the interface between hot and cool interstellar gases could contribute significantly to the observed soft X-ray emission in star forming galaxies. We analyze the XMM-Newton/RGS spectrum of M82, using a newly developed CX model combined with a single-temperature thermal plasma to characterize the volume-filling hot gas. The CX process is largely responsible for not only the strongly enhanced forbidden lines of the K$\\alpha$ triplets of various He-like ions, but also good fractions of the Ly$\\alpha$ transitions of C VI (~87%), O VIII and N VII ($\\gtrsim$50%) as well. In total about a quarter of the X-ray flux in the RGS 6-30 \\AA\\ band originates in the CX. We infer an ion incident rate of $3\\times10^{51}\\,\\rm{s^{-1}}$ undergoing CX at the hot and cool gas interface, and an effective area of the interface as $\\sim2\\times10^{45}\\,{\\rm cm^2}$ that is one order of magnitude larger than the cross section of the global biconic outflow. With the CX contribu...

  15. Genetic defects of iron transport.

    Science.gov (United States)

    Bannerman, R M

    1976-09-01

    Five genetic traits in man and laboratory animals have major effects on iron transport. The heterogeneous condition, hemochromatosis, in some families appears to segregate as a Mendelian trait, and is associated with defective control of intestinal iron absorption. In the very rare human autosomal recessive trait, atransferrinemia, there is an almost total lack of transferrin and gross maldistribution of iron through the body. In mice, sex-linked anemia (an X-linked recessive trait) causes iron deficiency through defective iron absorption, at the "exit" step; a similar defect probably exists in placental iron transfer. In microcytic anemia of mice, an autosomal recessive trait, iron absorption is also impaired because of a defect of iron entry into cells, which is probably generalized. Belgrade rat anemia, less understood at present, also may involve a major disorder of iron metabolism. Study of these mutations has provided new knowledge of iron metabolism and its genetic control Their phenotypic interaction with nutritional factors, especially the form and quantity of iron in the diet, may provide new insights for the study of nutrition.

  16. Osmundiron, cleaved iron bars and slags (Osmundjern, kloder og kalotslagger)

    DEFF Research Database (Denmark)

    Buchwald, Vagn Fabritius

    1996-01-01

    Investigation of so-called Osmund iron, iron bars and slags from iron production in the medieval ages.......Investigation of so-called Osmund iron, iron bars and slags from iron production in the medieval ages....

  17. High efficiency iron electrode and additives for use in rechargeable iron-based batteries

    Energy Technology Data Exchange (ETDEWEB)

    Narayan, Sri R.; Prakash, G. K. Surya; Aniszfeld, Robert; Manohar, Aswin; Malkhandi, Souradip; Yang, Bo

    2017-02-21

    An iron electrode and a method of manufacturing an iron electrode for use in an iron-based rechargeable battery are disclosed. In one embodiment, the iron electrode includes carbonyl iron powder and one of a metal sulfide additive or metal oxide additive selected from the group of metals consisting of bismuth, lead, mercury, indium, gallium, and tin for suppressing hydrogen evolution at the iron electrode during charging of the iron-based rechargeable battery. An iron-air rechargeable battery including an iron electrode comprising carbonyl iron is also disclosed, as is an iron-air battery wherein at least one of the iron electrode and the electrolyte includes an organosulfur additive.

  18. X-ray emission from the blazar AO 0235+16: the XMM-Newton and Chandra point of view

    CERN Document Server

    Raiteri, C M; Kadler, M; Krichbaum, T P; Böttcher, M; Fuhrmann, L; Orio, M

    2006-01-01

    In this paper we analyse five observations of the BL Lac object AO 0235+16 performed with the Chandra and XMM-Newton satellites during the years 2000-2005. In the February 2002 observation the source is found in a bright state and presents a steep X-ray spectrum, while in all the other epochs it is faint and the spectrum is hard. The soft X-ray spectrum appears to be strongly absorbed, likely by the intervening system at z=0.524, which also absorbs the optical-UV radiation. We find that models that consider spectral curvature are superior to single power law ones in fitting the X-ray spectrum. In particular, we favour a double power law model, which agrees with the assumption of a superposition of two different components in the X-ray domain. Both in the Chandra and in one of the XMM-Newton observations, a tentative detection of the redshifted Fe Kalpha emission line may suggest its origin from the inner part of an accretion disc. Thermal emission from this accretion disc might explain the UV-soft-X-ray bump ...

  19. Blood and hair lead in children with different extents of iron deficiency in Karachi

    Energy Technology Data Exchange (ETDEWEB)

    Ataur Rahman, Muhammad; Rahman, Bushra [Karachi Institute of Biotechnology and Genetic Engineering, University of Karachi, Karachi-75270 (Pakistan); Saeed Ahmad, Muhammad [School of Healthcare Science, Manchester Metropolitan University, Manchester M1 5GD (United Kingdom); Blann, Andrew [Department of Medicine, City Hospital, Birmingham B18 7QH, United Kingdom. (United Kingdom); Ahmed, Nessar, E-mail: N.Ahmed@mmu.ac.uk [School of Healthcare Science, Manchester Metropolitan University, Manchester M1 5GD (United Kingdom)

    2012-10-15

    Childhood iron deficiency has a high incidence in Pakistan. Some but not all studies have shown that dietary iron deficiency may cause increased absorption of lead as both compete for the same transporters in the small intestine. Therefore, children in Pakistan, residing in heavily polluted cities like Karachi may be prone to lead poisoning. This hypothesis was tested by investigating blood and hair lead concentrations in children from Karachi who were divided into four groups of iron status; normal, borderline iron deficiency, iron deficiency and iron deficiency anaemia. A prospective observational study was conducted where 269 children were categorized into four groups of iron status using the World Health Organization criteria and one based on soluble transferrin receptor measurements. Blood iron status was determined using a full blood count, serum iron, ferritin, transferrin saturation and soluble transferrin receptor measurements. Blood lead was determined by graphite atomic absorption spectroscopy, whereas hair lead was assessed using an inductively coupled plasma atomic emission spectroscopy technique. Blood lead concentrations were significantly higher in children with iron deficiency anaemia (mean [95% confidence intervals] were 24.9 [22.6-27.2] {mu}g/dL) compared to those with normal iron status (19.1 [16.8-21.4] {mu}g/dL) using WHO criteria. In contrast, hair lead content was not significantly different in children of different iron status. Our findings reinforce the importance of not only reducing environmental lead pollution but also the development of national health strategies to reduce childhood iron deficiency in Pakistan.

  20. Studies on the pathogenesis in iron deficiency anemia Part 1. Urinary iron excretion in iron deficiency anemia patients and rats in various iron states

    OpenAIRE

    1991-01-01

    In the "iron excretion test" , urinary iron excretion after injection of saccharated iron oxide has been reported to be accelerated in relapsing idiopathic iron deficiency anemia. To determine the relevance of urinary iron excretion to clinical factors other than iron metabolism, 15 clinical parameters were evaluated. The serum creatinine level was positively and the serum albumin level was negatively correlated with urinary iron excretion, showing coefficients of r=0.97,-0.86 respectively, a...

  1. Iron deficiency or anemia of inflammation?

    OpenAIRE

    Nairz, Manfred; Theurl, Igor; Wolf, Dominik; Weiss, Günter

    2016-01-01

    Summary Iron deficiency and immune activation are the two most frequent causes of anemia, both of which are based on disturbances of iron homeostasis. Iron deficiency anemia results from a reduction of the body’s iron content due to blood loss, inadequate dietary iron intake, its malabsorption, or increased iron demand. Immune activation drives a diversion of iron fluxes from the erythropoietic bone marrow, where hemoglobinization takes place, to storage sites, particularly the mononuclear ph...

  2. Studying Irony Detection Beyond Ironic Criticism: Let's Include Ironic Praise.

    Science.gov (United States)

    Bruntsch, Richard; Ruch, Willibald

    2017-01-01

    Studies of irony detection have commonly used ironic criticisms (i.e., mock positive evaluation of negative circumstances) as stimulus materials. Another basic type of verbal irony, ironic praise (i.e., mock negative evaluation of positive circumstances) is largely absent from studies on individuals' aptitude to detect verbal irony. However, it can be argued that ironic praise needs to be considered in order to investigate the detection of irony in the variety of its facets. To explore whether the detection ironic praise has a benefit beyond ironic criticism, three studies were conducted. In Study 1, an instrument (Test of Verbal Irony Detection Aptitude; TOVIDA) was constructed and its factorial structure was tested using N = 311 subjects. The TOVIDA contains 26 scenario-based items and contains two scales for the detection of ironic criticism vs. ironic praise. To validate the measurement method, the two scales of the TOVIDA were experimentally evaluated with N = 154 subjects in Study 2. In Study 3, N = 183 subjects were tested to explore personality and ability correlates of the two TOVIDA scales. Results indicate that the co-variance between the ironic TOVIDA items was organized by two inter-correlated but distinct factors: one representing ironic praise detection aptitude and one representing ironic criticism detection aptitude. Experimental validation showed that the TOVIDA items truly contain irony and that item scores reflect irony detection. Trait bad mood and benevolent humor (as a facet of the sense of humor) were found as joint correlates for both ironic criticism and ironic praise detection scores. In contrast, intelligence, trait cheerfulness, and corrective humor were found as unique correlates of ironic praise detection scores, even when statistically controlling for the aptitude to detect ironic criticism. Our results indicate that the aptitude to detect ironic praise can be seen as distinct from the aptitude to detect ironic criticism. Generating

  3. Development of an automated in situ analyzer based on ferrozine colorimetry and flow injection analysis to analyze iron in freshwater systems

    Science.gov (United States)

    Cooray, A. T.; Schwingle, R.; Pullin, M. J.

    2011-12-01

    Iron is a common element in the earth crust and also a highly redox active metal in aqueous environments. The chemistry of aqueous iron predominantly involves the common oxidation states of iron, Fe(II) and Fe(III) and their biogeochemical reactions in the oceans, freshwaters, sediments and pore waters. Iron(III) is the thermodynamically stable form of iron in oxic and circumneutral natural waters; however, rapidly hydrolyzes and precipitates and become biologically unavailable. Iron(II) is more soluble and available for many microbial iron uptake strategies but rapidly oxidizes in oxic waters with a half-life in the order of minutes around pH 8. The often rapid interconversion of iron redox states makes in situ analysis preferable. Here we describe the development of an automated in situ iron analyzer based on ferrozine colorimetry and flow injection analysis (FIA) to analyze iron in freshwater systems. Ferrozine selectively reacts with iron(II) in the pH range 4 to 9 to produce a magenta colored 3:1 complex with a maximum absorption at 562 nm. Ferrozine does not react with iron(III) or any of its hydrolytic products. However, total iron determinations can be achieved use reducing agents such as ascorbic acid to reduce iron(III) to iron(II). Ferrozine colorimetry has been used successfully to develop automated iron sensors for marine systems and freshwater systems. Unlike luminol-based chemiluminescence methods, the ferrozine method is not sensitive to the amount of dissolved organic matter present in system or the temperature variations during the analysis. The instrument uses microscale tubing and fittings together with solenoid-based pumps and valves for flow control. Optical detection of the iron(II)-ferrozine complex uses a LED lamp with maximum emission at 560 nm and digital light sensor to avoid the use of complex optics. The instrument analyzes iron(II) and total iron in alternation, with a frequency of 4 minutes.

  4. Iron deficiency and cardiovascular disease.

    Science.gov (United States)

    von Haehling, Stephan; Jankowska, Ewa A; van Veldhuisen, Dirk J; Ponikowski, Piotr; Anker, Stefan D

    2015-11-01

    Iron deficiency affects up to one-third of the world's population, and is particularly common in elderly individuals and those with certain chronic diseases. Iron excess can be detrimental in cardiovascular illness, and research has now also brought anaemia and iron deficiency into the focus of cardiovascular medicine. Data indicate that iron deficiency has detrimental effects in patients with coronary artery disease, heart failure (HF), and pulmonary hypertension, and possibly in patients undergoing cardiac surgery. Around one-third of all patients with HF, and more than one-half of patients with pulmonary hypertension, are affected by iron deficiency. Patients with HF and iron deficiency have shown symptomatic improvements from intravenous iron administration, and some evidence suggests that these improvements occur irrespective of the presence of anaemia. Improved exercise capacity has been demonstrated after iron administration in patients with pulmonary hypertension. However, to avoid iron overload and T-cell activation, it seems that recipients of cardiac transplantations should not be treated with intravenous iron preparations.

  5. Iron Curtains ?

    OpenAIRE

    Maria Vlček

    2010-01-01

    This paper explores the emotional and multi-sensorial dimensions of care within a transnational family separated by the Iron Curtain during the Cold War. It will argue that processes of supportive and compassionate engagement amongst transnational kin are not only shaped by long-distance communication, financial support and practical help within specific political and economic contexts, but also by personal desires and interpersonal conflict. The dialectics of proximity and distance are explo...

  6. Iron and Prochlorococcus

    Science.gov (United States)

    2009-06-01

    some cyanobacteria has been investigated through culture-based and genomic approaches (Ferreira and Straus, 1994; Katoh et al, 2001; Kutzki, 1998...numerically abundant marine cyanobacterium, Prochlorococcus. With its minimal genome and ubiquity in the global ocean, Prochlorococcus represents a model...then examined the molecular basis for the ability of MIT9313 to grow at lower iron concentrations than MED4 by assessing whole- genome transcription

  7. NuSTAR Hard X-ray Survey of the Galactic Center Region I: Hard X-ray Morphology and Spectroscopy of the Diffuse Emission

    CERN Document Server

    Mori, Kaya; Krivonos, Roman; Hong, Jaesub; Ponti, Gabriele; Bauer, Franz; Perez, Kerstin; Nynka, Melania; Zhang, Shuo; Tomsick, John A; Alexander, David M; Baganoff, Frederick K; Barret, Didier; Barriere, Nicolas; Boggs, Steven E; Canipe, Alicia M; Christensen, Finn E; Craig, William W; Forster, Karl; Giommi, Paolo; Grefenstette, Brian W; Grindlay, Jonathan E; Harrison, Fiona A; Hornstrup, Allan; Kitaguchi, Takao; Koglin, Jason E; Luu, Vy; Madsen, Kristen K; Mao, Peter H; Miyasaka, Hiromasa; Perri, Matteo; Pivovaroff, Michael J; Puccetti, Simonetta; Rana, Vikram; Stern, Daniel; Westergaard, Niels J; Zhang, William W; Zoglauer, Andreas

    2015-01-01

    We present the first sub-arcminute images of the Galactic Center above 10 keV, obtained with NuSTAR. NuSTAR resolves the hard X-ray source IGR J17456-2901 into non-thermal X-ray filaments, molecular clouds, point sources and a previously unknown central component of hard X-ray emission (CHXE). NuSTAR detects four non-thermal X-ray filaments, extending the detection of their power-law spectra with $\\Gamma\\sim1.3$-$2.3$ up to ~50 keV. A morphological and spectral study of the filaments suggests that their origin may be heterogeneous, where previous studies suggested a common origin in young pulsar wind nebulae (PWNe). NuSTAR detects non-thermal X-ray continuum emission spatially correlated with the 6.4 keV Fe K$\\alpha$ fluorescence line emission associated with two Sgr A molecular clouds: MC1 and the Bridge. Broad-band X-ray spectral analysis with a Monte-Carlo based X-ray reflection model self-consistently determined their intrinsic column density ($\\sim10^{23}$ cm$^{-2}$), primary X-ray spectra (power-laws wi...

  8. Flare Plasma Iron Abundance

    Science.gov (United States)

    Dennis, Brian R.; Dan, Chau; Jain, Rajmal; Schwartz, Richard A.; Tolbert, Anne K.

    2008-01-01

    The equivalent width of the iron-line complex at 6.7 keV seen in flare X-ray spectra suggests that the iron abundance of the hottest plasma at temperatures >approx.10 MK may sometimes be significantly lower than the nominal coronal abundance of four times the photospheric value that is commonly assumed. This conclusion is based on X-ray spectral observations of several flares seen in common with the Ramaty High Energy Solar Spectroscopic Imager (RHESSI) and the Solar X-ray Spectrometer (SOXS) on the second Indian geostationary satellite, GSAT-2. The implications of this will be discussed as it relates to the origin of the hot flare plasma - either plasma already in the corona that is directly heated during the flare energy release process or chromospheric plasma that is heated by flare-accelerated particles and driven up into the corona. Other possible explanations of lower-than-expected equivalent widths of the iron-line complex will also be discussed.

  9. Iron homeostasis: new players, newer insights.

    Science.gov (United States)

    Edison, Eunice S; Bajel, Ashish; Chandy, Mammen

    2008-12-01

    Although iron is a relatively abundant element in the universe, it is estimated that more than 2 billion people worldwide suffer from iron deficiency anemia. Iron deficiency results in impaired production of iron-containing proteins, the most prominent of which is hemoglobin. Cellular iron deficiency inhibits cell growth and subsequently leads to cell death. Hemochromatosis, an inherited disorder results in disproportionate absorption of iron and the extra iron builds up in tissues resulting in organ damage. As both iron deficiency and iron overload have adverse effects, cellular and systemic iron homeostasis is critically important. Recent advances in the field of iron metabolism have led to newer understanding of the pathways involved in iron homeostasis and the diseases which arise from alteration in the regulators. Although insight into this complex regulation of the proteins involved in iron homeostasis has been obtained mainly through animal studies, it is most likely that this knowledge can be directly extrapolated to humans.

  10. Intestinal Iron Homeostasis and Colon Tumorigenesis

    Directory of Open Access Journals (Sweden)

    Yatrik M. Shah

    2013-06-01

    Full Text Available Colorectal cancer (CRC is the third most common cause of cancer-related deaths in industrialized countries. Understanding the mechanisms of growth and progression of CRC is essential to improve treatment. Iron is an essential nutrient for cell growth. Iron overload caused by hereditary mutations or excess dietary iron uptake has been identified as a risk factor for CRC. Intestinal iron is tightly controlled by iron transporters that are responsible for iron uptake, distribution, and export. Dysregulation of intestinal iron transporters are observed in CRC and lead to iron accumulation in tumors. Intratumoral iron results in oxidative stress, lipid peroxidation, protein modification and DNA damage with consequent promotion of oncogene activation. In addition, excess iron in intestinal tumors may lead to increase in tumor-elicited inflammation and tumor growth. Limiting intratumoral iron through specifically chelating excess intestinal iron or modulating activities of iron transporter may be an attractive therapeutic target for CRC.

  11. CO2 Abatement In The Iron And Steel Industry

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    2012-01-15

    The iron and steel industry is the largest industrial source of CO2 emissions due to the energy intensity of steel production, its reliance on carbon-based fuels and reductants, and the large volume of steel produced -- over 1414 Mt in 2010. With the growing concern over climate change, steel makers are faced with the challenge of finding ways of lowering CO2 emissions without seriously undermining process efficiency or considerably adding to costs. This report examines ways of abating CO2 emissions from raw materials preparation (coking, sintering and pelletising plants) through to the production of liquid steel in basic oxygen furnaces and electric arc furnaces. Direct reduction and smelting reduction processes are covered, as well as iron making in a blast furnace. A range of technologies and measures exist for lowering CO2 emissions including minimising energy consumption and improving energy efficiency, changing to a fuel and/or reducing agent with a lower CO2 emission factor (such as wood charcoal), and capturing the CO2 and storing it underground. Significant CO2 reductions can be achieved by combining a number of the available technologies. If carbon capture and storage is fitted than steel plants could become near zero emitters of CO2.

  12. Air pollution–aerosol interactions produce more bioavailable iron for ocean ecosystems

    Science.gov (United States)

    Li, Weijun; Xu, Liang; Liu, Xiaohuan; Zhang, Jianchao; Lin, Yangting; Yao, Xiaohong; Gao, Huiwang; Zhang, Daizhou; Chen, Jianmin; Wang, Wenxing; Harrison, Roy M.; Zhang, Xiaoye; Shao, Longyi; Fu, Pingqing; Nenes, Athanasios; Shi, Zongbo

    2017-01-01

    It has long been hypothesized that acids formed from anthropogenic pollutants and natural emissions dissolve iron (Fe) in airborne particles, enhancing the supply of bioavailable Fe to the oceans. However, field observations have yet to provide indisputable evidence to confirm this hypothesis. Single-particle chemical analysis for hundreds of individual atmospheric particles collected over the East China Sea shows that Fe-rich particles from coal combustion and steel industries were coated with thick layers of sulfate after 1 to 2 days of atmospheric residence. The Fe in aged particles was present as a “hotspot” of (insoluble) iron oxides and throughout the acidic sulfate coating in the form of (soluble) Fe sulfate, which increases with degree of aging (thickness of coating). This provides the “smoking gun” for acid iron dissolution, because iron sulfate was not detected in the freshly emitted particles and there is no other source or mechanism of iron sulfate formation in the atmosphere. PMID:28275731

  13. Air pollution-aerosol interactions produce more bioavailable iron for ocean ecosystems.

    Science.gov (United States)

    Li, Weijun; Xu, Liang; Liu, Xiaohuan; Zhang, Jianchao; Lin, Yangting; Yao, Xiaohong; Gao, Huiwang; Zhang, Daizhou; Chen, Jianmin; Wang, Wenxing; Harrison, Roy M; Zhang, Xiaoye; Shao, Longyi; Fu, Pingqing; Nenes, Athanasios; Shi, Zongbo

    2017-03-01

    It has long been hypothesized that acids formed from anthropogenic pollutants and natural emissions dissolve iron (Fe) in airborne particles, enhancing the supply of bioavailable Fe to the oceans. However, field observations have yet to provide indisputable evidence to confirm this hypothesis. Single-particle chemical analysis for hundreds of individual atmospheric particles collected over the East China Sea shows that Fe-rich particles from coal combustion and steel industries were coated with thick layers of sulfate after 1 to 2 days of atmospheric residence. The Fe in aged particles was present as a "hotspot" of (insoluble) iron oxides and throughout the acidic sulfate coating in the form of (soluble) Fe sulfate, which increases with degree of aging (thickness of coating). This provides the "smoking gun" for acid iron dissolution, because iron sulfate was not detected in the freshly emitted particles and there is no other source or mechanism of iron sulfate formation in the atmosphere.

  14. A review on steam-iron process as a hydrogen production/purifying/storage option

    Energy Technology Data Exchange (ETDEWEB)

    Ort, Nesibe; Yoruk, Sedat [Ataturk University, Department of Chemical Engineering (Turkey)], e-mail: nesibe.ort@atauni.edu.tr, email: syoruk@atauni.edu.tr; Dilmac, Omer F. [Yyldyz Technical University, Department of Chemical Engineering (Turkey)], email: omerfarukdl@yahoo.com

    2011-07-01

    The fuel cell has the potential to become an important energy sector technology in the future, thanks to its ability to produce electrical energy from chemical energy with a high efficiency and without emission of pollutants. Fuel cells require pure hydrogen which is at the moment mainly produced by the steam methane reforming process. However, interest is growing in the steam iron process due to its ability to produce high purity hydrogen. The aim of this paper is to provide information on the steam iron process through a review of recent research on the subject. This review showed that 100% pure hydrogen can be produced with the steam iron process and that removal of contaminants is minimal in this process; in addition iron is a non-toxic, inexpensive and stable material. This review highlighted that the steam iron process can be a good alternative for hydrogen production, purification and storage.

  15. Iron deficiency in the young athlete.

    Science.gov (United States)

    Rowland, T W

    1990-10-01

    Although overt anemia is uncommon, depletion of body iron stores is common among adolescent female athletes. Poor dietary iron intake, menstruation, and increased iron losses associated with physical training all appear to be important factors. Whether nonanemic iron deficiency can impair exercise performance is uncertain. Nonetheless, athletes with low ferritin levels are at risk for impaired erythropoiesis and should receive therapeutic iron supplementation.

  16. Microbial reduction of iron ore

    Science.gov (United States)

    Hoffmann, Michael R.; Arnold, Robert G.; Stephanopoulos, Gregory

    1989-01-01

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

  17. Diagnostic Accuracy of Serum Iron and Total Iron Binding Capacity (TIBC) in Iron Deficiency State.

    Science.gov (United States)

    Asif, Naveed; Ijaz, Aamir; Rafi, Tariq; Haroon, Zujaja Hina; Bashir, Saima; Ayyub, Muhammad

    2016-12-01

    To determine the diagnostic accuracy of serum iron and total iron binding capacity (TIBC) in detection of iron deficiency. Descriptive, analytical study. Department of Chemical Pathology and Endocrinology, from January 2013 to October 2015. Data of 1,815 patients with results of serum iron, TIBC and ferritin from January 2013 to October 2015 was retrieved from Laboratory information System (LIMS) of AFIP. Diagnostic Accuracy Studies (STARD) guidelines were followed. Subjects of either gender, aged 1 - 68 years were included. Cases with raised serum ferritin levels (male > 336 ng/ml, female > 307 ng/ml) were excluded. Serum Ferritin was taken as gold standard with specificity of 99% and sensitivity of 80% at concentration of 30 ng/ml. Transferrin saturation was determined by dividing serum iron by TIBC and multiplying by 100. Out of 1,815 subjects, 931 (51.29%) were males and 884 (48.71%) were females. The median age of the patients were 29.1 years (Inter-quartile range, IQR 19.1). Taking ferritin as gold standard, the sensitivity and specificity of serum iron was 63.5% and 38.6%, respectively; while that of TIBC was 64.5 % and 42.8%, respectively. Ferritin showed poor correlation with iron, TIBC and transferrin saturation. Serum iron and TIBC give no additional information in the diagnosis of iron deficiency anemia and these tests are redundant for the diagnosis of iron deficiency state, if serum ferritin is available.

  18. The irony of iron -- biogenic iron oxides as an iron source to the ocean

    Directory of Open Access Journals (Sweden)

    David eEmerson

    2016-01-01

    Full Text Available Primary productivity in at least a third of the sunlit open ocean is thought to be iron-limited. Primary sources of dissolved iron (dFe to the ocean are hydrothermal venting, flux from the sediments along continental margins, and airborne dust. This article provides a general review of sources of hydrothermal and sedimentary iron to the ocean, and speculates upon the role that iron-cycling microbes play in controlling iron dynamics from these sources. Special attention is paid to iron-oxidizing bacteria (FeOB that live by oxidizing iron and producing biogenic iron oxides as waste products. The presence and ubiquity of FeOB both at hydrothermal systems and in sediments is only beginning to be appreciated. The biogenic oxides they produce have unique properties that could contribute significantly to the dynamics of dFe in the ocean. Changes in the physical and chemical characteristics of the ocean due to climate change and ocean acidification will undoubtedly impact the microbial iron cycle. A better understanding of the contemporary role of microbes in the iron cycle will help in predicting how these changes could ultimately influence marine primary productivity.

  19. Iron in Skin of Mice with Three Etiologies of Systemic Iron Overload

    OpenAIRE

    2005-01-01

    In human hemochromatosis, tissue toxicity is a function of tissue iron levels. Despite reports of skin toxicity in hemochromatosis, little is known about iron levels in skin of individuals with systemic iron overload. We measured skin iron and studied skin histology in three mouse models of systemic iron overload: mice with a deletion of the hemochromatosis (Hfe) gene, mice fed a high iron diet, and mice given parenteral injections of iron. In Hfe−/− mice, iron content in the epidermis and de...

  20. Pathogenic Mechanisms Underlying Iron Deficiency and Iron Overload: New Insights for Clinical Application

    OpenAIRE

    Kotze, MJ; van Velden, DP; van Rensburg, SJ; Erasmus, R

    2009-01-01

    Iron uptake, utilisation, release and storage occur at the gene level. Individuals with variant forms of genes involved in iron metabolism may have different requirements for iron and are likely to respond differently to the same amount of iron in the diet, a concept termed nutrigenetics. Iron deficiency, iron overload and the anemia of inflammation are the commonest iron-related disorders. While at least four types of hereditary iron overload have been identified to date, our knowledge of th...

  1. Iron and Ferritin Levels in Saliva of Patients with Thalassemia and Iron Deficiency Anemia

    OpenAIRE

    Canatan, Duran; Akdeniz, Sevgi Kosaci

    2012-01-01

    Most of the techniques for measuring iron stores such as serum iron concentration, iron binding capacity, serum ferritin level, liver biopsy can be troublesome or invasive for patients with thalassemia. The salivary iron measurement could be of potential advantage being an easy and non invasive approach for diagnosis of iron deficiency and iron overload . The aim of this study was to compare the levels of iron and ferritin in saliva and serum of patients affected by thalassemia or iron defici...

  2. Performance of Nonmigratory Iron Chelating Active Packaging Materials in Viscous Model Food Systems.

    Science.gov (United States)

    Roman, Maxine J; Decker, Eric A; Goddard, Julie M

    2015-09-01

    Many packaged food products undergo quality deterioration due to iron promoted oxidative reactions. Recently, we have developed a nonmigratory iron chelating active packaging material that represents a novel approach to inhibit oxidation of foods while addressing consumer demands for "cleanˮ labels. A challenge to the field of nonmigratory active packaging is ensuring that surface-immobilized active agents retain activity in a true food system despite diffusional limitations. Yet, the relationship between food viscosity and nonmigratory active packaging activity retention has never been characterized. The objective of this study was to investigate the influence of food viscosity on iron chelation by a nonmigratory iron chelating active packaging material. Methyl cellulose was added to aqueous buffered iron solutions to yield model systems with viscosities ranging from ∼1 to ∼10(5)  mPa·s, representing viscosities ranging from beverage to mayonnaise. Iron chelation was quantified by material-bound iron content using colorimetry and inductively coupled plasma-optical emission spectrometry (ICP-OES).  Maximum iron chelation was reached in solutions up to viscosity ∼10(2)  mPa·s. In more viscous solutions (up to ∼10(4)  mPa·s), there was a significant decrease in iron chelating capacity (P influence of different food hydrocolloids on the performance of nonmigratory iron chelating active packaging was characterized. Methyl cellulose and carrageenan did not compete with the material for specific iron chelation (P > 0.05). Materials retained 32% to 45% chelating capacity when in contact with competitively chelating hydrocolloids guar gum, locust bean gum, and xanthan gum. This work demonstrates the potential application of nonmigratory iron chelating active packaging in liquid and semi-liquid foods to allow for the removal of synthetic chelators, while maintaining food quality.

  3. Management of Iron Deficiency Anemia

    OpenAIRE

    Jimenez, Kristine; Kulnigg-Dabsch, Stefanie; Gasche, Christoph

    2015-01-01

    Anemia affects one-fourth of the world’s population, and iron deficiency is the predominant cause. Anemia is associated with chronic fatigue, impaired cognitive function, and diminished well-being. Patients with iron deficiency anemia of unknown etiology are frequently referred to a gastroenterologist because in the majority of cases the condition has a gastrointestinal origin. Proper management improves quality of life, alleviates the symptoms of iron deficiency, and reduces the need for blo...

  4. Iron fortification and iron supplementation are cost-effective interventions to reduce iron deficiency in four subregions of the world

    NARCIS (Netherlands)

    C. Knai; M. Sharan; R.M.P.M. Baltussen (Rob)

    2004-01-01

    textabstractIron deficiency is the most common and widespread nutritional disorder in the world, affecting millions of people in both nonindustrialized and industrialized countries. We estimated the costs, effects, and cost-effectiveness of iron supplementation and iron

  5. Iron fortification and iron supplementation are cost-effective interventions to reduce iron deficiency in four subregions of the world

    NARCIS (Netherlands)

    C. Knai; M. Sharan; R.M.P.M. Baltussen (Rob)

    2004-01-01

    textabstractIron deficiency is the most common and widespread nutritional disorder in the world, affecting millions of people in both nonindustrialized and industrialized countries. We estimated the costs, effects, and cost-effectiveness of iron supplementation and iron fortificati

  6. 46 CFR 56.60-10 - Cast iron and malleable iron.

    Science.gov (United States)

    2010-10-01

    ... 46 Shipping 2 2010-10-01 2010-10-01 false Cast iron and malleable iron. 56.60-10 Section 56.60-10... APPURTENANCES Materials § 56.60-10 Cast iron and malleable iron. (a) The low ductility of cast iron and malleable iron should be recognized and the use of these metals where shock loading may occur should...

  7. 49 CFR 192.489 - Remedial measures: Cast iron and ductile iron pipelines.

    Science.gov (United States)

    2010-10-01

    ... 49 Transportation 3 2010-10-01 2010-10-01 false Remedial measures: Cast iron and ductile iron... for Corrosion Control § 192.489 Remedial measures: Cast iron and ductile iron pipelines. (a) General graphitization. Each segment of cast iron or ductile iron pipe on which general graphitization is found to...

  8. Chemiluminescence of iron-chlorophyllin.

    Science.gov (United States)

    Nagoshi, Toshimasa; Ohno, Osamu; Kotake, Tomohiko; Igarashi, Shukuro

    2005-01-01

    The iron-chlorophyllin complex was found to be chemiluminescent (CL) in an acetonitrile (22%)/water mixed solvent. In the presence of hydrogen peroxide, when iron-chlorophyllin was added to the mixed solvent, a sharp CL signal immediately appeared. Also, analysis of the absorption spectra revealed decomposition of iron-chlorophyllin (based on decrease in absorbance at 396 nm), hence iron-chlorophyllin is the CL substance. Moreover, the CL intensity decreased in the presence of potassium thiocyanate (KSCN), indicating that the axial coordinative position of iron-chlorophyllin acts as a point of catalytic activation. In addition, when fluorophores were present with iron-chlorophyllin CL, their CL intensity values were similar to or greater than that of the well-known trichlorophenylperoxalate ester (TCPO) CL. Thus, during the decomposition reaction of iron-chlorophyllin, the latter transfers its energy to the coexisting fluorophores. Moreover, since the decomposed compound in this CL reaction had a fluorescence, it was found that the iron-chlorophyllin also functions as an energy donor. Therefore, the iron-chlorophyllin complex acts not only as a CL substance, but also as a catalyst and energy donor in the reaction.

  9. Phytases for Improved Iron Absorption

    DEFF Research Database (Denmark)

    Nielsen, Anne Veller Friis; Nyffenegger, Christian; Meyer, Anne S.

    2014-01-01

    Microbial phytases (EC 3.1.3.8) catalyse dephosphorylation of phytic acid, which is the primary storage compound for phosphorous in cereal kernels. The negatively charged phosphates in phytic acid chelate iron (Fe3+) and thus retards iron bioavailability in humans 1. Supplementation of microbial...... phytase can improve iron absorption from cereal-based diets 2. In order for phytase to catalyse iron release in vivo the phytase must be robust to low pH and proteolysis in the gastric ventricle. Our work has compared the robustness of five different microbial phytases, evaluating thermal stability...

  10. Retinoic acid and iron metabolism

    DEFF Research Database (Denmark)

    Chakraborty, Surajit; Bhattacharyya, Rajasri; Sayal, Kirtimaan

    2014-01-01

    tuberculosis controlling molecules in the days to come. Iron has proven to be essential for pathogenesis of tuberculosis and retinoic acid is known to influence the iron metabolism pathway. Retenoic acid is also known to exhibit antitubercular effect in in vivo system. Therefore there is every possibility...... that retinoic acid by affecting the iron metabolism pathway exhibits its antimycobacterial effect. These aspects are reviewed in the present manuscript for understanding the antimycobacterial role of retinoic acid in the context of iron metabolism and other immunological aspects....

  11. Iron Deficiency Anemia in Pregnancy.

    Science.gov (United States)

    Breymann, Christian

    2015-10-01

    Anemia is a common problem in obstetrics and perinatal care. Any hemoglobin below 10.5 g/dL can be regarded as true anemia regardless of gestational age. Reasons for anemia in pregnancy are mainly nutritional deficiencies, parasitic and bacterial diseases, and inborn red blood cell disorders such as thalassemias. The main cause of anemia in obstetrics is iron deficiency, which has a worldwide prevalence between estimated 20%-80% and consists of a primarily female population. Stages of iron deficiency are depletion of iron stores, iron-deficient erythropoiesis without anemia, and iron deficiency anemia, the most pronounced form of iron deficiency. Pregnancy anemia can be aggravated by various conditions such as uterine or placental bleedings, gastrointestinal bleedings, and peripartum blood loss. In addition to the general consequences of anemia, there are specific risks during pregnancy for the mother and the fetus such as intrauterine growth retardation, prematurity, feto-placental miss ratio, and higher risk for peripartum blood transfusion. Besides the importance of prophylaxis of iron deficiency, the main therapy options for the treatment of pregnancy anemia are oral iron and intravenous iron preparations.

  12. Iron-Refractory Iron Deficiency Anemia

    Directory of Open Access Journals (Sweden)

    Ebru Yılmaz Keskin

    2015-03-01

    Full Text Available Demir, oksijenin taşınması, DNA sentezi ve hücre çoğalması gibi çeşitli biyolojik reaksiyonlar için vazgeçilmez olduğundan, yaşam için zorunludur. Demir metabolizması ve bu elementin düzenlenmesiyle ilgili bilgilerimiz, son yıllarda belirgin şekilde değişmiştir. Demir metabolizması ile ilgili yeni bozukluklar tanımlanmış ve demirin başka bozuklukların kofaktörü olduğu anlaşılmaya başlamıştır. Hemokromatozis ve demir tedavisine dirençli demir eksikliği anemisi (IRIDA; “iron-refractory iron deficiency anemia” gibi genetik durumlar üzerinde yapılan çalışmalar, vücuttaki demir dengesini kontrol eden moleküler mekanizmalar ile ilgili önemli ipuçları sunmuştur. Bu ilerlemeler, gelecekte, hem genetik hem de kazanılmış demir bozukluklarının daha etkili şekilde tedavi edilmesi amacıyla kullanılabilir. IRIDA, demir eksikliği ile giden durumlarda, hepsidin üretimini baskılayan matriptaz-2’yi kodlayan TMPRSS6 genindeki mutasyonlardan kaynaklanmaktadır. Hastalığın tipik özellikleri, hipokrom, mikrositer anemi, çok düşük ortalama eritrosit hacmi, oral demir tedavisine yanıtsızlık (veya yetersiz yanıt ve parenteral demire kısmi yanıttır. Klasik demir eksikliği anemisinin aksine, serum ferritin değeri genellikle hafif düşük ya da normal aralıkta; serum ve idrar hepsidin değerleri ise, aneminin derecesi ile orantısız şekilde yüksek bulunur. Şimdiye kadar literatürde bildirilmiş olguların sayısı 100’ü geçmediği halde, IRIDA’nın, “atipik” mikrositik anemilerin en sık nedeni olduğu düşünülmektedir. Bu derlemenin amacı, IRIDA hakkındaki güncel bilgileri araştırıcılar ile paylaşmak ve bu alandaki farkındalıklarını arttırmaktır.

  13. Catalytic effect of free iron ions and heme-iron on chromophore oxidation of a polyene antibiotic amphotericin B

    Science.gov (United States)

    Czernel, Grzegorz; Typek, Rafał; Klimek, Katarzyna; Czuryło, Aleksandra; Dawidowicz, Andrzej L.; Gagoś, Mariusz

    2016-05-01

    Owing to the presence of a chromophore in the amphotericin B (AmB) structure, the molecule can undergo the oxidation process. In this research, AmB chromophore oxidation was catalysed by iron ions (iron(III) chloride (FeCl3), pH 2.5) and by heme-iron (methemoglobin (HbFe(III)), and hemin (heme-Fe(III)) at pH 7.0). Additionally, we compared oxidation processes induced by the aforementioned oxidizing agents with autoxidation by dioxygen (O2) naturally occurring in a sample. The effects of the interaction of the oxidizing agents with AmB were analysed using molecular spectroscopies (electronic absorption (UV-Vis), fluorescence) and LC-MS. The use of a 1,10-phenanthroline (phen) chelator facilitated unambiguous determination of the oxidative effect of free iron(III) ions (FeIII) in an acidic solution on the AmB molecules. Also, the changes in the spectra of fluorescence emission centred at ∼470 nm indicate iron-catalysed processes of AmB chromophore oxidation. Unexpectedly, we found a similar spectroscopic effect for AmB induced by methemoglobin and hemin at pH 7.0. Methemoglobin and hemin at a concentration of 8 × 10-7 M (physiological) significantly increases the rate of the processes of AmB chromophore oxidation relative to the process of autoxidation.

  14. Particulate Matter Emissions Factors for Dust from Unique Military Activities

    Science.gov (United States)

    2010-06-01

    good assumption for desert dust in the absence of iron oxides, especially hematite (Fe2O3)). In the SI-1400 method, particle size distribution is...shear stress imparted to the surface. The PI-SWERL is being used increasingly as a primary tool to evaluate windblown dust emissions from natural and...surface, so the amount of charge should be the primary control on emission strength for a given surface. 26 Table 3. Minimum, maximum, mean and

  15. Nanosized Iron Oxide Colloids Strongly Enhance Microbial Iron Reduction▿ †

    Science.gov (United States)

    Bosch, Julian; Heister, Katja; Hofmann, Thilo; Meckenstock, Rainer U.

    2010-01-01

    Microbial iron reduction is considered to be a significant subsurface process. The rate-limiting bioavailability of the insoluble iron oxyhydroxides, however, is a topic for debate. Surface area and mineral structure are recognized as crucial parameters for microbial reduction rates of bulk, macroaggregate iron minerals. However, a significant fraction of iron oxide minerals in the subsurface is supposed to be present as nanosized colloids. We therefore studied the role of colloidal iron oxides in microbial iron reduction. In batch growth experiments with Geobacter sulfurreducens, colloids of ferrihydrite (hydrodynamic diameter, 336 nm), hematite (123 nm), goethite (157 nm), and akaganeite (64 nm) were added as electron acceptors. The colloidal iron oxides were reduced up to 2 orders of magnitude more rapidly (up to 1,255 pmol h−1 cell−1) than bulk macroaggregates of the same iron phases (6 to 70 pmol h−1 cell−1). The increased reactivity was not only due to the large surface areas of the colloidal aggregates but also was due to a higher reactivity per unit surface. We hypothesize that this can be attributed to the high bioavailability of the nanosized aggregates and their colloidal suspension. Furthermore, a strong enhancement of reduction rates of bulk ferrihydrite was observed when nanosized ferrihydrite aggregates were added. PMID:19915036

  16. Iron and iron-related proteins in asbestosis.

    Science.gov (United States)

    ABSTRACT: We tested the postulate that iron homeostasis is altered among patients diagnosed to have asbestosis. Lung tissue from six individuals diagnosed to have had asbestosis at autopsy was stained for iron, ferritin, divalent metal transporter 1 (DMT1), and ferroportin 1 (FP...

  17. Core-shell iron-iron oxide nanoparticles

    DEFF Research Database (Denmark)

    Kuhn, Luise Theil; Bojesen, A.; Timmermann, L.

    2004-01-01

    We present studies of the magnetic properties of core-shell iron-iron oxide nanoparticles. By combining Mossbauer and X-ray absorption spectroscopy we have been able to measure the change from a Fe3O4-like to a gamma-Fe2O3-like composition from the interface to the surface. Furthermore, we have...

  18. Iron and iron-related proteins in asbestosis.

    Science.gov (United States)

    ABSTRACT: We tested the postulate that iron homeostasis is altered among patients diagnosed to have asbestosis. Lung tissue from six individuals diagnosed to have had asbestosis at autopsy was stained for iron, ferritin, divalent metal transporter 1 (DMT1), and ferroportin 1 (FP...

  19. measurements of iron status and survival in african iron overload

    African Journals Online (AJOL)

    iron status to diagnose this form of iron overload has not been clarified. Methods. ..... U-test and categorical variables were compared with the Fisher exact or the Pearson ..... 5eftel He, Keeley Iq, lsaacson C, BothweU TH. Siderosis in the ...

  20. Iron oxide surfaces

    Science.gov (United States)

    Parkinson, Gareth S.

    2016-03-01

    The current status of knowledge regarding the surfaces of the iron oxides, magnetite (Fe3O4), maghemite (γ-Fe2O3), haematite (α-Fe2O3), and wüstite (Fe1-xO) is reviewed. The paper starts with a summary of applications where iron oxide surfaces play a major role, including corrosion, catalysis, spintronics, magnetic nanoparticles (MNPs), biomedicine, photoelectrochemical water splitting and groundwater remediation. The bulk structure and properties are then briefly presented; each compound is based on a close-packed anion lattice, with a different distribution and oxidation state of the Fe cations in interstitial sites. The bulk defect chemistry is dominated by cation vacancies and interstitials (not oxygen vacancies) and this provides the context to understand iron oxide surfaces, which represent the front line in reduction and oxidation processes. Fe diffuses in and out from the bulk in response to the O2 chemical potential, forming sometimes complex intermediate phases at the surface. For example, α-Fe2O3 adopts Fe3O4-like surfaces in reducing conditions, and Fe3O4 adopts Fe1-xO-like structures in further reducing conditions still. It is argued that known bulk defect structures are an excellent starting point in building models for iron oxide surfaces. The atomic-scale structure of the low-index surfaces of iron oxides is the major focus of this review. Fe3O4 is the most studied iron oxide in surface science, primarily because its stability range corresponds nicely to the ultra-high vacuum environment. It is also an electrical conductor, which makes it straightforward to study with the most commonly used surface science methods such as photoemission spectroscopies (XPS, UPS) and scanning tunneling microscopy (STM). The impact of the surfaces on the measurement of bulk properties such as magnetism, the Verwey transition and the (predicted) half-metallicity is discussed. The best understood iron oxide surface at present is probably Fe3O4(100); the structure is

  1. Iron-Deficiency Anemia (For Parents)

    Science.gov (United States)

    ... TV, Video Games, and the Internet Iron-Deficiency Anemia KidsHealth > For Parents > Iron-Deficiency Anemia Print A ... common nutritional deficiency in children. About Iron-Deficiency Anemia Every red blood cell in the body contains ...

  2. Iron Meteorites and Upwelling in Antarctica

    Science.gov (United States)

    Gourlay, B. S.; Behr, E.; Mardon, A.; Behr, E.

    2016-09-01

    In Antarctica, a meteorite stranding zone, stone meteorites are more common than iron. Dr. Evatt's team suggests that the heat conductivity of iron may be opposing the upwelling effects so iron meteorites sink under the ice unlike the stone ones.

  3. Iron-Deficiency Anemia (For Parents)

    Science.gov (United States)

    ... Your 1- to 2-Year-Old Iron-Deficiency Anemia KidsHealth > For Parents > Iron-Deficiency Anemia A A ... common nutritional deficiency in children. About Iron-Deficiency Anemia Every red blood cell in the body contains ...

  4. Iron-based superconductivity

    CERN Document Server

    Johnson, Peter D; Yin, Wei-Guo

    2015-01-01

    This volume presents an in-depth review of experimental and theoretical studies on the newly discovered Fe-based superconductors.  Following the Introduction, which places iron-based superconductors in the context of other unconventional superconductors, the book is divided into three sections covering sample growth, experimental characterization, and theoretical understanding.  To understand the complex structure-property relationships of these materials, results from a wide range of experimental techniques and theoretical approaches are described that probe the electronic and magnetic proper

  5. Amorphous iron (II) carbonate

    DEFF Research Database (Denmark)

    Sel, Ozlem; Radha, A.V.; Dideriksen, Knud;

    2012-01-01

    exothermic than that of amorphous calcium carbonate (ACC). This suggests that enthalpy of crystallization in carbonate systems is ionic-size controlled, which may have significant implications in a wide variety of conditions, including geological sequestration of anthropogenic carbon dioxide.......Abstract The synthesis, characterization and crystallization energetics of amorphous iron (II) carbonate (AFC) are reported. AFC may form as a precursor for siderite (FeCO3). The enthalpy of crystallization (DHcrys) of AFC is similar to that of amorphous magnesium carbonate (AMC) and more...

  6. Low-carbon transition of iron and steel industry in China: carbon intensity, economic growth and policy intervention.

    Science.gov (United States)

    Yu, Bing; Li, Xiao; Qiao, Yuanbo; Shi, Lei

    2015-02-01

    As the biggest iron and steel producer in the world and one of the highest CO2 emission sectors, China's iron and steel industry is undergoing a low-carbon transition accompanied by remarkable technological progress and investment adjustment, in response to the macroeconomic climate and policy intervention. Many drivers of the CO2 emissions of the iron and steel industry have been explored, but the relationships between CO2 abatement, investment and technological expenditure, and their connections with the economic growth and governmental policies in China, have not been conjointly and empirically examined. We proposed a concise conceptual model and an econometric model to investigate this crucial question. The results of regression, Granger causality test and impulse response analysis indicated that technological expenditure can significantly reduce CO2 emissions, and that investment expansion showed a negative impact on CO2 emission reduction. It was also argued with empirical evidence that a good economic situation favored CO2 abatement in China's iron and steel industry, while achieving CO2 emission reduction in this industrial sector did not necessarily threaten economic growth. This shed light on the dispute over balancing emission cutting and economic growth. Regarding the policy aspects, the year 2000 was found to be an important turning point for policy evolution and the development of the iron and steel industry in China. The subsequent command and control policies had a significant, positive effect on CO2 abatement.

  7. Reducing iron deficiency anemia in Bolivian school children: calcium and iron combined versus iron supplementation alone.

    Science.gov (United States)

    Miranda, Melissa; Olivares, Manuel; Brito, Alex; Pizarro, Fernando

    2014-01-01

    The aim of this study was to determine the effect of combined calcium and iron versus single iron supplementation on iron status in Bolivian schoolchildren. Children ages 6 to 10 y old (N = 195), were randomly assigned to receive either 700 mg Ca (as calcium carbonate) plus 30 mg Fe (as ferrous sulfate) (Ca + Fe group) or 30 mg Fe (as ferrous sulfate) (Fe group). The doses were administered daily, from Monday to Friday, between meals at school over 3 mo. Iron status was assessed at baseline and after intervention. Additionally, overall nutritional status was assessed by anthropometry and an estimation of dietary intake. At baseline, the prevalence of anemia in the Ca + Fe group and the Fe group were 15% and 21.5%, respectively. After 3 mo follow-up, the prevalence of iron deficiency anemia dropped significantly (P Iron dietary intake was within recommended levels, but calcium intake only covered 39% of the Recommended Daily Intake. Combined calcium and iron supplementation is equally as effective as single iron supplementation in reducing the prevalence of iron deficiency anemia in Bolivian school children. Copyright © 2014 Elsevier Inc. All rights reserved.

  8. K alpha line emission during solar X-ray bursts

    Science.gov (United States)

    Phillips, K. J. H.; Neupert, W. M.

    1973-01-01

    The expected flux of K alpha line emission from sulfur, argon, calcium, and iron is calculated during both thermal and nonthermal solar X-ray events. Such emission is shown to be weak during the course of most of the nonthermal hard X-ray bursts that Kane and Anderson (1970) have observed. If Compton backscattering is significant at high energies, the flux is reduced still further for disk flares, but it is noted that the strong, near-limb burst of June 26 would have produced about 100 photons /sq cm/sec of sulfur and iron K alpha emission. The impulsive hard X-ray bursts may in general be too short-lived for much K alpha emission. It may be noted that sulfur K alpha emission in particular depends sensitively on the lower-energy limit of the nonthermal electron spectrum, assuming such a sharply defined boundary exists. During soft X-ray bursts, when temperatures of a few 10 to the 7th power K are obtained, K alpha emission from certain iron ions, specifically Fe XVIII-XXIII, may be important.

  9. Shielding data for 100 250 MeV proton accelerators: Attenuation of secondary radiation in thick iron and concrete/iron shields

    Science.gov (United States)

    Agosteo, S.; Magistris, M.; Mereghetti, A.; Silari, M.; Zajacova, Z.

    2008-08-01

    Double differential distributions of neutrons produced by 100, 150, 200 and 250 MeV protons stopped in a thick iron target were calculated with the FLUKA Monte Carlo code at four emission angles: forward, 45°, transverse and 135° backwards. The attenuation in thick iron shields of the dose equivalent due to neutrons, protons, photons and electrons was also calculated. The contribution to the total ambient dose equivalent from photons and protons is limited to a few percent at maximum. Source terms and attenuation lengths are given as a function of energy and emission angle, along with fits to the Monte Carlo data, for shallow depth and deep penetration in the shield. A brief discussion of simulations performed with composite iron/concrete shields is also given, showing the need for further investigations.

  10. The Pharmacokinetics and Pharmacodynamics of Iron Preparations

    Directory of Open Access Journals (Sweden)

    Susanna Burckhardt

    2011-01-01

    Full Text Available Standard approaches are not appropriate when assessing pharmacokinetics of iron supplements due to the ubiquity of endogenous iron, its compartmentalized sites of action, and the complexity of the iron metabolism. The primary site of action of iron is the erythrocyte, and, in contrast to conventional drugs, no drug-receptor interaction takes place. Notably, the process of erythropoiesis, i.e., formation of new erythrocytes, takes 3−4 weeks. Accordingly, serum iron concentration and area under the curve (AUC are clinically irrelevant for assessing iron utilization. Iron can be administered intravenously in the form of polynuclear iron(III-hydroxide complexes with carbohydrate ligands or orally as iron(II (ferrous salts or iron(III (ferric complexes. Several approaches have been employed to study the pharmacodynamics of iron after oral administration. Quantification of iron uptake from radiolabeled preparations by the whole body or the erythrocytes is optimal, but alternatively total iron transfer can be calculated based on known elimination rates and the intrinsic reactivity of individual preparations. Degradation kinetics, and thus the safety, of parenteral iron preparations are directly related to the molecular weight and the stability of the complex. High oral iron doses or rapid release of iron from intravenous iron preparations can saturate the iron transport system, resulting in oxidative stress with adverse clinical and subclinical consequences. Appropriate pharmacokinetics and pharmacodynamics analyses will greatly assist our understanding of the likely contribution of novel preparations to the management of anemia.

  11. The pharmacokinetics and pharmacodynamics of iron preparations.

    Science.gov (United States)

    Geisser, Peter; Burckhardt, Susanna

    2011-01-04

    Standard approaches are not appropriate when assessing pharmacokinetics of iron supplements due to the ubiquity of endogenous iron, its compartmentalized sites of action, and the complexity of the iron metabolism. The primary site of action of iron is the erythrocyte, and, in contrast to conventional drugs, no drug-receptor interaction takes place. Notably, the process of erythropoiesis, i.e., formation of new erythrocytes, takes 3-4 weeks. Accordingly, serum iron concentration and area under the curve (AUC) are clinically irrelevant for assessing iron utilization. Iron can be administered intravenously in the form of polynuclear iron(III)-hydroxide complexes with carbohydrate ligands or orally as iron(II) (ferrous) salts or iron(III) (ferric) complexes. Several approaches have been employed to study the pharmacodynamics of iron after oral administration. Quantification of iron uptake from radiolabeled preparations by the whole body or the erythrocytes is optimal, but alternatively total iron transfer can be calculated based on known elimination rates and the intrinsic reactivity of individual preparations. Degradation kinetics, and thus the safety, of parenteral iron preparations are directly related to the molecular weight and the stability of the complex. High oral iron doses or rapid release of iron from intravenous iron preparations can saturate the iron transport system, resulting in oxidative stress with adverse clinical and subclinical consequences. Appropriate pharmacokinetics and pharmacodynamics analyses will greatly assist our understanding of the likely contribution of novel preparations to the management of anemia.

  12. Colour Metallography of Cast Iron

    Institute of Scientific and Technical Information of China (English)

    Zhou Jiyang; Liu Jincheng

    2010-01-01

    @@ Spheroidal Graphite Cast Iron(Ⅲ) 3.6 Solidification morphology of SG iron Solidification morphology refers to the description of change,distribution and interrelationship of the solidification structures such as graphite spheroids,austenite,eutectic cells,etc.[99

  13. Hunting for Iron Ore Bargains

    Institute of Scientific and Technical Information of China (English)

    2009-01-01

    One of China’s leading steel mills has turned to smaller mines for long-term, lowcost iron ore supplies china’s oldest steel producer is looking to South America to fulfill its iron ore needs in the face of rising prices from

  14. Adsorptive Iron Removal from Groundwater

    NARCIS (Netherlands)

    Sharma, S.K.

    2001-01-01

    Iron is commonly present in groundwater worldwide. The presence of iron in drinking water is not harmful to human health, however it is undesirable because of the associated aesthetic and operational problems, namely: bad taste, colour, stains on laundry and plumbing fixtures, and aftergrowth in the

  15. Adsorptive iron removal from groundwater

    NARCIS (Netherlands)

    Sharma, S.K.

    2001-01-01

    Iron is commonly present in groundwater worldwide. The presence of iron in the water supply is not harmful to human health, however it is undesirable. Bad taste, discoloration, staining, deposition in the distribution system leading to aftergrowth, and incidences of high turbidity are some

  16. Chandra/HETGS Spectroscopy of the Galactic Black Hole GX 339-4: A Relativistic Iron Line and Evidence for a Seyfert-like Warm Absorber

    CERN Document Server

    Miller, J M; Fabian, A C; Homan, J; Nowak, M A; Wijnands, R; Van der Klis, M; Belloni, T; Tomsick, J A; Smith, D M; Charles, P A; Lewin, W H G

    2004-01-01

    We observed the Galactic black hole GX 339-4 with the Chandra High Energy Transmission Grating Spectrometer (HETGS) for 75 ksec during the decline of its 2002-2003 outburst. The sensitivity of this observation provides an unprecedented glimpse of a Galactic black hole at about a tenth of the luminosity of the outburst peak. The continuum spectrum is well described by a model consisting of multicolor disk blackbody (kT = 0.6 keV) and power-law (Gamma = 2.5) components. X-ray reflection models yield improved fits. A strong, relativistic Fe K-alpha emission line is revealed, indicating that the inner disk extends to the innermost stable circular orbit. The line is not sufficiently broad to strongly require black hole spin. Absorption lines from H-like and He-like O, and He-like Ne and Mg are detected, as well as lines which are likely due to Ne II and Ne III. The measured line properties make it difficult to associate the absorption with the coronal phase of the interstellar medium. A scenario wherein the absorp...

  17. Iron deficiency in the tropics.

    Science.gov (United States)

    Fleming, A F

    1982-06-01

    Iron in food is classified as belonging to the haem pool, the nonhaem pool, and extraneous sources. Haem iron is derived from vegetable and animal sources with varying bioavailability. Hookworm infestation of the intestinal tract affects 450 million people in the tropics. Schistosoma mansoni caused blood loss in 7 Egyptian patients of 7.5- 25.9 ml/day which is equivalent to a daily loss of iron of .6-7.3 mg daily urinary loss of iron in 9 Egyptian patients. Trichuris trichiura infestation by whipworm is widespread in children with blood loss of 5 ml/day/worm. The etiology of anemia in children besides iron deficiency includes malaria, bacterial or viral infections, folate deficiency and sickle-cell disease. Severe infections cause profound iron-deficiency anemia in children in central American and Malaysia. Plasmodium falciparum malaria-induced anaemia in tropical Africa lowers the mean haemoglobin concentration in the population by 2 g/dI, causing profound anaemia in some. The increased risk of premature delivery, low birthweight, fetal abnormalities, and fetal death is directly related to the degree of maternal anemia. Perinatal mortality was reduced from 38 to 4% in treated anemic mothers. Mental performance was significantly lower in anemic school children and improved after they received iron. Supplements of iron, soy-protein, calcium, and vitamins given to villagers with widespread malnutrition, iron deficiency, and hookworm infestation in Colombia reduced enteric infections in children. Severe iron-deficiency anemia was treated in adults in northern Nigeria by daily in Ferastral 10 ml, which is equivalent to 500 mg of iron per day. Choloroquine, folic acid, rephenium hydroxynaphthoate, and tetrachlorethylene treat adults with severe iron deficiency from hookworm infestation in rural tropical Africa. Blood transfusion is indicated if the patient is dying of anaemia or is pregnant with a haemoglobin concentration 6 gm/dl. In South East Asia, mg per day

  18. Iron deficiency in blood donors

    Directory of Open Access Journals (Sweden)

    Armando Cortés

    2005-03-01

    Full Text Available Context: Blood donation results in a substantial loss of iron (200 to 250 mg at each bleeding procedure (425 to 475 ml and subsequent mobilization of iron from body stores. Recent reports have shown that body iron reserves generally are small and iron depletion is more frequent in blood donors than in non-donors. Objective: The aim of this study was to evaluate the frequency of iron deficiency in blood donors and to establish the frequency of iron deficiency in blood donors according to sex, whether they were first-time or multi-time donors. Design: From march 20 to April 5, 2004, three hundred potential blood donors from Hemocentro del Café y Tolima Grande were studied. Diagnostic tests: Using a combination of biochemical measurements of iron status: serum ferritin (RIA, ANNAR and the hemoglobin pre and post-donation (HEMOCUE Vital technology medical . Results: The frequency of iron deficiency in potential blood donors was 5%, and blood donors accepted was 5.1%; in blood donors rejected for low hemoglobin the frequency of iron deficiency was 3.7% and accepted blood donors was 1.7% in male and 12.6% in female. The frequency of iron deficiency was higher in multi-time blood donors than in first-time blood donors, but not stadistic significative. Increase nivel accepted hemoglobina in 1 g/dl no incidence in male; in female increase of 0.5 g/dl low in 25% blood donors accepted with iron deficiency, but increased rejected innecesary in 16.6% and increased is 1 g/dl low blood donors female accepted in 58% (7/12, but increased the rejected innecesary in 35.6%. Conclusions: We conclude that blood donation not is a important factor for iron deficiency in blood donors. The high frequency of blood donors with iron deficiency found in this study suggests a need for a more accurate laboratory trial, as hemoglobin or hematocrit measurement alone is not sufficient for detecting and excluding blood donors with iron deficiency without anemia, and ajustes hacia

  19. Anthropogenic mercury emissions from 1980 to 2012 in China.

    Science.gov (United States)

    Huang, Ying; Deng, Meihua; Li, Tingqiang; Japenga, Jan; Chen, Qianqian; Yang, Xiaoe; He, Zhenli

    2017-07-01

    China was considered the biggest contributor for airborne mercury in the world but the amount of mercury emission in effluents and solid wastes has not been documented. In this study, total national and regional mercury emission to the environment via exhaust gases, effluents and solid wastes were accounted with updated emission factors and the amount of goods produced and/or consumed. The national mercury emission in China increased from 448 to 2151 tons during the 1980-2012 period. Nearly all of the emissions were ended up as exhaust gases and solid wastes. The proportion of exhaust gases decreased with increasing share of solid wastes and effluents. Of all the anthropogenic sources, coal was the most important contributor in quantity, followed by mercury mining, gold smelting, nonferrous smelting, iron steel production, domestic wastes, and cement production, with accounting for more than 90% of the total emission. There was a big variation of regional cumulative mercury emission during 1980-2012 in China, with higher emissions occurred in eastern areas and lower values in the western and far northern regions. The biggest cumulative emission occurred in GZ (Guizhou), reaching 3974 t, while the smallest cumulative emission was lower than 10 t in XZ (Tibet). Correspondingly, mercury accumulation in soil were higher in regions with larger emissions in unit area. Therefore, it is urgent to reduce anthropogenic mercury emission and subsequent impact on ecological functions and human health. Copyright © 2017. Published by Elsevier Ltd.

  20. Responsiveness to parenteral iron therapy in children with oral iron-refractory iron-deficiency anemia.

    Science.gov (United States)

    Akin, Mehmet; Atay, Enver; Oztekin, Osman; Karadeniz, Cem; Karakus, Yasin Tugrul; Yilmaz, Bilal; Erdogan, Firat

    2014-02-01

    Intravenous (IV) ferric iron (Fe)-carbohydrate complexes are used for treating Fe deficiency in children with iron-refractory iron-deficiency anemia (IRIDA). An optimal treatment has yet to be determined. There are relatively little publications on the responsiveness to IV iron therapy in children with IRIDA. This study analyzed responses to IV iron sucrose therapy given to 11 children, ranging in age from 2 to 13 years (mean 4.8 years), with iron-deficiency anemia who were unresponsive to oral iron therapy. The hemoglobin and ferritin values (mean) of the 11 children with IRIDA were 7.7 g/dL and 4.8 ng/mL at diagnosis. Both hemoglobin and ferritin levels increased to 9.5 g/dL, and 24 ng/mL, respectively, at 6 weeks after the first therapy. Although the level of hemoglobin was steady at 6 months after the first, and 6 weeks after the second therapy, the ferritin levels continued to increase up to 30 ng/mL and 47 ng/mL at 6 months after the first and 6 weeks after the second therapy, respectively. We recommend that IRIDA should be considered in patients presenting with iron-deficiency anemia of unknown cause that is unresponsive to oral iron therapy. Our results suggest that IV iron therapy should be administered only once in cases of IRIDA. Continued administration of IV iron would be of no benefit to increase hemoglobin levels. On the contrary, ferritin levels may continue to increase resulting in untoward effects of hyperferritinemia.

  1. Comparative study of oral iron and intravenous iron sucrose for the treatment of iron deficiency anemia in pregnancy

    Directory of Open Access Journals (Sweden)

    Apurva Garg

    2016-12-01

    Full Text Available Background: The aim of this study was to compare the efficacy and safety of iron sucrose with oral iron in the treatment of iron deficiency anemia of pregnancy. Methods: An interventional comparative study was conducted at Jhalawar Medical College, Jhalawar involving 80 pregnant women with iron deficiency anemia from March 2016 to August 2016. Inclusion criteria were gestational age between 24-32 weeks with established iron deficiency anemia, with hemoglobin between 7-10g/dl. Target Hemoglobin was 11 g/dl. In intravenous iron sucrose group iron sucrose dose was calculated from following formula: total iron dose required (mg = 2.4 x body weight in Kg x (target Hb – Patient’s Hb g/dl + 500. In oral iron, group patient received ferrous-sulphate 335 mg daily BD. Hb level were reviewed at 2, 4, 6 weeks. Results: Change in Hemoglobin level from baseline significantly higher in IV iron group than oral iron group. In IV iron, group mean value of baseline Hb was 8.07±0.610 g/dl and in oral iron group was 8.48±0.741 g/dl. At the end of 6-week mean hemoglobin in IV iron sucrose was 10.66±0.743 g/dl and in oral iron group was 10.08±0.860 g/dl. Conclusions: Intravenous iron sucrose elevates more Hb than oral iron, with less adverse effects.

  2. Smelting reduction and kinetics analysis of magnetic iron in copper slag using waste cooking oil.

    Science.gov (United States)

    Li, Bo; Wang, Xubin; Wang, Hua; Wei, Yonggang; Hu, Jianhang

    2017-05-25

    To improve the recovery of copper, the viscosity of copper molten slag is decreased by the reduction of magnetic iron, which, in turn, accelerates the settling and separation of copper droplets from the slag. A new technology is proposed in which waste cooking oil is used as a reductant to reduce magnetic iron in the copper smelting slag and consequently reduce carbon emissions in the copper smelting process. A kinetic model of the reduction of magnetic iron in copper slag by waste cooking oil was built using experimental data, and the accuracy of the model was verified. The results indicated that the magnetic iron content in the copper slag decreased with increasing reduction time and an increase in temperature more efficiently reduced magnetic iron in the copper slag. The magnetic iron in the copper slag gradually transformed to fayalite, and the viscosity of the copper molten slag decreased as the magnetic iron content decreased during the reduction process. The reduction of magnetic iron in the copper molten slag using waste cooking oil was a first-order reaction, and the rate-limiting step was the mass transfer of Fe3O4 through the liquid boundary layer.

  3. Pathology of hepatic iron overload

    Institute of Scientific and Technical Information of China (English)

    Yves Deugnier; Bruno Turlin

    2007-01-01

    Although progress in imaging and genetics allow for a noninvasive diagnosis of most cases of genetic iron overload, liver pathology remains often useful (1) to assess prognosis by grading fibrosis and seeking for associated lesions and (2) to guide the etiological diagnosis, especially when no molecular marker is available.Then, the type of liver siderosis (parenchymal, mesenchymal or mixed) and its distribution throughout the lobule and the liver are useful means for suggesting its etiology: HLA-linked hemochromatosis gene (HFE) hemochromatosis or other rare genetic hemochromatosis,nonhemochromatotic genetic iron overload (ferroportin disease, aceruloplasminemia), or iron overload secondary to excessive iron supply, inflammatory syndrome,noncirrhotic chronic liver diseases including dysmetabolic iron overload syndrome, cirrhosis, and blood disorders.

  4. Iron and Mechanisms of Neurotoxicity

    Directory of Open Access Journals (Sweden)

    Gabriela A. Salvador

    2011-01-01

    Full Text Available The accumulation of transition metals (e.g., copper, zinc, and iron and the dysregulation of their metabolism are a hallmark in the pathogenesis of several neurodegenerative diseases. This paper will be focused on the mechanism of neurotoxicity mediated by iron. This metal progressively accumulates in the brain both during normal aging and neurodegenerative processes. High iron concentrations in the brain have been consistently observed in Alzheimer's (AD and Parkinson's (PD diseases. In this connection, metalloneurobiology has become extremely important in establishing the role of iron in the onset and progression of neurodegenerative diseases. Neurons have developed several protective mechanisms against oxidative stress, among them, the activation of cellular signaling pathways. The final response will depend on the identity, intensity, and persistence of the oxidative insult. The characterization of the mechanisms mediating the effects of iron-induced increase in neuronal dysfunction and death is central to understanding the pathology of a number of neurodegenerative disorders.

  5. Development of volume deposition on cast iron by additive manufacturing

    Energy Technology Data Exchange (ETDEWEB)

    Niyanth S, Niyanth [ORNL; Dehoff, Ryan R [ORNL; Jordan, Brian H [ORNL; Babu, Suresh S. [University of Tennessee (UTK) and Oak Ridge National Laboratory (ORNL)

    2016-11-10

    ORNL partnered with Cummins to demonstrate the feasibility of using additive manufacturing techniques to help develop repair techniques for refurbished cast iron engine blocks. Cummins is interested in the refurbished engine business due to the increased cost savings and reduced emissions. It is expected that by refurbishing engines could help reduce the green house gas emissions by as much as 85%. Though such repair techniques are possible in principle there has been no major industry in the automotive sector that has deployed this technology. Therefore phase-1 would seek to evaluate the feasibility of using the laser directed energy deposition technique to repair cast iron engine blocks. The objective of the phase-1 would be to explore various strategies and understand the challenges involved. During phase-1 deposits were made using Inconel-718, Nickel, Nr-Cr-B braze filler. Inconel 718 builds showed significant cracking in the heat-affected zone in the cast iron. Nickel was used to reduce the cracking in the cast iron substrate, however the Ni builds did not wet the substrate sufficiently resulting in poor dimensional tolerance. In order to increase wetting the Ni was alloyed with the Ni-Cr-B braze to decrease the surface tension of Ni. This however resulted in significant cracks in the build due to shrinkage stresses associated with multiple thermal cycling. Hence to reduce the residual stresses in the builds the DMD-103D equipment was modified and the cast iron block was pre heated using cartridge heaters. Inconel-718 alloyed with Ni was deposited on the engine block. The pre-heated deposits showed a reduced susceptibility to cracking. If awarded the phase-2 of the project would aim to develop process parameters to achieve a crack free deposit engine block.

  6. Microbial acquisition of iron from ferric iron bearing minerals

    Energy Technology Data Exchange (ETDEWEB)

    Hersman, L.E. [Los Alamos National Lab., NM (United States); Sposito, G. [Univ. of California, Berkeley, CA (United States)

    1998-12-31

    This is the final report of a three-year, Laboratory Directed Research and Development (LDRD) project at the Los Alamos National Laboratory (LANL). Iron is a universal requirement for all life forms. Although the fourth most abundant element in the geosphere, iron is virtually insoluble at physiological pH in oxidizing environments, existing mainly as very insoluble oxides and hydroxides. Currently it is not understood how iron is solubilized and made available for biological use. This research project addressed this topic by conducting a series of experiments that utilized techniques from both soil microbiology and mineral surface geochemistry. Microbiological analysis consisted of the examination of metabolic and physiological responses to mineral iron supplements. At the same time mineral surfaces were examined for structural changes brought about by microbially mediated dissolution. The results of these experiments demonstrated that (1) bacterial siderophores were able to promote the dissolution of iron oxides, (2) that strict aerobic microorganisms may use anaerobic processes to promote iron oxide dissolution, and (3) that it is possible to image the surface of iron oxides undergoing microbial dissolution.

  7. The Regulation of Iron Absorption and Homeostasis

    Science.gov (United States)

    Wallace, Daniel F

    2016-01-01

    Iron is an essential element in biology, required for numerous cellular processes. Either too much or too little iron can be detrimental, and organisms have developed mechanisms for balancing iron within safe limits. In mammals there are no controlled mechanisms for the excretion of excess iron, hence body iron homeostasis is regulated at the sites of absorption, utilisation and recycling. This review will discuss the discoveries that have been made in the past 20 years into advancing our understanding of iron homeostasis and its regulation. The study of iron-associated disorders, such as the iron overload condition hereditary haemochromatosis and various forms of anaemia have been instrumental in increasing our knowledge in this area, as have cellular and animal model studies. The liver has emerged as the major site of systemic iron regulation, being the location where the iron regulatory hormone hepcidin is produced. Hepcidin is a negative regulator of iron absorption and recycling, achieving this by binding to the only known cellular iron exporter ferroportin and causing its internalisation and degradation, thereby reducing iron efflux from target cells and reducing serum iron levels. Much of the research in the iron metabolism field has focussed on the regulation of hepcidin and its interaction with ferroportin. The advances in this area have greatly increased our knowledge of iron metabolism and its regulation and have led to the development of novel diagnostics and therapeutics for iron-associated disorders.

  8. CO2 emissions in the steel industry

    Directory of Open Access Journals (Sweden)

    M. Kundak

    2009-07-01

    Full Text Available Global CO2 emissions caused by the burning of fossil fuels over the past century are presented. Taking into consideration the total world production of more than 1,3 billion tons of steel, the steel industry produces over two billion tons of CO2. Reductions in CO2 emissions as a result of technological improvements and structural changes in steel production in industrialized countries during the past 40 years are described. Substantial further reductions in those emissions will not be possible using conventional technologies. Instead, a radical cutback may be achieved if, instead of carbon, hydrogen is used for direct iron ore reduction. The cost and the ensuing CO2 generation in the production of hydrogen as a reducing agent from various sources are analysed.

  9. Southern Ocean Iron Experiment (SOFex)

    Energy Technology Data Exchange (ETDEWEB)

    Coale, Kenneth H.

    2005-07-28

    The Southern Ocean Iron Experiment (SOFeX) was an experiment decades in the planning. It's implementation was among the most complex ship operations that SIO has been involved in. The SOFeX field expedition was successful in creating and tracking two experimentally enriched areas of the Southern Ocean, one characterized by low silicic acid, one characterized by high silicic acid. Both experimental sites were replete with abundant nitrate. About 100 scientists were involved overall. The major findings of this study were significant in several ways: (1) The productivity of the southern ocean is limited by iron availability. (2) Carbon uptake and flux is therefore controlled by iron availability (3) In spite of low silicic acid, iron promotes non-silicious phytoplankton growth and the uptake of carbon dioxide. (4) The transport of fixed carbon from the surface layers proceeds with a C:N ratio that would indicate differential remineralization of nitrogen at shallow depths. (5) These finding have major implications for modeling of carbon export based on nitrate utilization. (6) The general results of the experiment indicate that, beyond other southern ocean enrichment experiments, iron inputs have a much wider impact of productivity and carbon cycling than previously demonstrated. Scientific presentations: Coale, K., Johnson, K, Buesseler, K., 2002. The SOFeX Group. Eos. Trans. AGU 83(47) OS11A-0199. Coale, K., Johnson, K. Buesseler, K., 2002. SOFeX: Southern Ocean Iron Experiments. Overview and Experimental Design. Eos. Trans. AGU 83 (47) OS22D-01. Buesseler, K.,et al. 2002. Does Iron Fertilization Enhance Carbon Sequestration? Particle flux results from the Southern Ocean Iron Experiment. Eos. Trans. AGU 83 (47), OS22D-09. Johnson, K. et al. 2002. Open Ocean Iron Fertilization Experiments From IronEx-I through SOFeX: What We Know and What We Still Need to Understand. Eos. Trans. AGU 83 (47), OS22D-12. Coale, K. H., 2003. Carbon and Nutrient Cycling During the

  10. Deficiency of α-1-antitrypsin influences systemic iron homeostasis

    Directory of Open Access Journals (Sweden)

    Ghio AJ

    2013-01-01

    Full Text Available Andrew J Ghio,1 Joleen M Soukup,1 Judy H Richards,1 Bernard M Fischer,2 Judith A Voynow,2 Donald E Schmechel31US Environmental Protection Agency, Chapel Hill, NC, USA; 2Division of Pediatric Pulmonary Medicine, Department of Pediatrics,3Joseph and Kathleen Bryan Alzheimer Disease Research Center, Department of Medicine (Neurology, Duke University Medical Center, Durham, NC, USAAbstract: There is evidence that proteases and antiproteases participate in the iron homeostasis of cells and living systems. We tested the postulate that α-1 antitrypsin (A1AT polymorphism and the consequent deficiency of this antiprotease in humans are associated with a systemic disruption in iron homeostasis. Archived plasma samples from Alpha-1 Foundation (30 MM, 30 MZ, and 30 ZZ individuals were analyzed for A1AT, ferritin, transferrin, and C-reactive protein (CRP. Plasma samples were also assayed for metals using inductively coupled plasma atomic emission spectroscopy (ICPAES. Plasma levels of A1AT in MZ and ZZ individuals were approximately 60% and 20% of those for MM individuals respectively. Plasma ferritin concentrations in those with the ZZ genotype were greater relative to those individuals with either MM or MZ genotype. Plasma transferrin for MM, MZ, and ZZ genotypes showed no significant differences. Linear regression analysis revealed a significant (negative relationship between plasma concentrations of A1AT and ferritin while that between A1AT and transferrin levels was not significant. Plasma CRP concentrations were not significantly different between MM, MZ, and ZZ individuals. ICPAES measurement of metals confirmed elevated plasma concentrations of nonheme iron among ZZ individuals. Nonheme iron concentrations correlated (negatively with levels of A1AT. A1AT deficiency is associated with evidence of a disruption in iron homeostasis with plasma ferritin and nonheme iron concentrations being elevated among those with the ZZ genotype.Keywords: α-1

  11. Computational Design of Short Pulse Laser Driven Iron Opacity Measurements at Stellar-Relevant Conditions

    Energy Technology Data Exchange (ETDEWEB)

    Martin, Madison E. [Univ. of Florida, Gainesville, FL (United States)

    2017-05-20

    Opacity is a critical parameter in the simulation of radiation transport in systems such as inertial con nement fusion capsules and stars. The resolution of current disagreements between solar models and helioseismological observations would bene t from experimental validation of theoretical opacity models. Overall, short pulse laser heated iron experiments reaching stellar-relevant conditions have been designed with consideration of minimizing tamper emission and optical depth effects while meeting plasma condition and x-ray emission goals.

  12. High temperature oxidation of iron-iron oxide core-shell nanowires composed of iron nanoparticles.

    Science.gov (United States)

    Krajewski, M; Brzozka, K; Lin, W S; Lin, H M; Tokarczyk, M; Borysiuk, J; Kowalski, G; Wasik, D

    2016-02-07

    This work describes an oxidation process of iron-iron oxide core-shell nanowires at temperatures between 100 °C and 800 °C. The studied nanomaterial was synthesized through a simple chemical reduction of iron trichloride in an external magnetic field under a constant flow of argon. The electron microscopy investigations allowed determining that the as-prepared nanowires were composed of self-assembled iron nanoparticles which were covered by a 3 nm thick oxide shell and separated from each other by a thin interface layer. Both these layers exhibited an amorphous or highly-disordered character which was traced by means of transmission electron microscopy and Mössbauer spectroscopy. The thermal oxidation was carried out under a constant flow of argon which contained the traces of oxygen. The first stage of process was related to slow transformations of amorphous Fe and amorphous iron oxides into crystalline phases and disappearance of interfaces between iron nanoparticles forming the studied nanomaterial (range: 25-300 °C). After that, the crystalline iron core and iron oxide shell became oxidized and signals for different compositions of iron oxide sheath were observed (range: 300-800 °C) using X-ray diffraction, Raman spectroscopy and Mössbauer spectroscopy. According to the thermal gravimetric analysis, the nanowires heated up to 800 °C under argon atmosphere gained 37% of mass with respect to their initial weight. The structure of the studied nanomaterial oxidized at 800 °C was mainly composed of α-Fe2O3 (∼ 93%). Moreover, iron nanowires treated above 600 °C lost their wire-like shape due to their shrinkage and collapse caused by the void coalescence.

  13. Iron Curtains ?

    Directory of Open Access Journals (Sweden)

    Maria Vlček

    2010-12-01

    Full Text Available This paper explores the emotional and multi-sensorial dimensions of care within a transnational family separated by the Iron Curtain during the Cold War. It will argue that processes of supportive and compassionate engagement amongst transnational kin are not only shaped by long-distance communication, financial support and practical help within specific political and economic contexts, but also by personal desires and interpersonal conflict. The dialectics of proximity and distance are explored through a focus on uses of communication technology, emotional interaction during visits, long-distance engagement through distinct sensorial experiences, and imaginary interaction through the dynamics of internalised presence. The auto/biographical analysis is mainly based on letters, faxes, diaries, interviews and personal memories.

  14. Iron Mountain Electromagnetic Results

    Energy Technology Data Exchange (ETDEWEB)

    Gail Heath

    2012-07-01

    Iron Mountain Mine is located seventeen miles northwest of Redding, CA. After the completion of mining in early 1960s, the mine workings have been exposed to environmental elements which have resulted in degradation in water quality in the surrounding water sheds. In 1985, the EPA plugged ore stoops in many of the accessible mine drifts in an attempt to restrict water flow through the mine workings. During this process little data was gathered on the orientation of the stoops and construction of the plugs. During the last 25 years, plugs have begun to deteriorate and allow acidic waters from the upper workings to flow out of the mine. A team from Idaho National Laboratory (INL) performed geophysical surveys on a single mine drift and 3 concrete plugs. The project goal was to evaluate several geophysical methods to determine competence of the concrete plugs and orientation of the stopes.

  15. Iron metabolism in burned children.

    Science.gov (United States)

    Belmonte, J A; Ibáñez, L; Ras, M R; Aulesa, C; Vinzo, J; Iglesias, J; Carol, J

    1999-07-01

    The administration of iron supplementation in children with burns has been a subject of controversy. Recent studies argue against its use in the acute phase of stress. To assess whether iron metabolism parameters show significant differences in the acute phase and the recovery phase of burn, 21 patients (age range: 17 months to 13 years) with burns of more than 10% of body surface who had not received blood transfusions or iron supplementation were studied. Sideraemia, ferritin, transferrin, transferrin saturation index (TSI) and C-reactive protein (CRP) were assessed both in the acute and the recovery phase after burn. Sideraemia, transferrin, and TSI were significantly lower in the acute than in the recovery phase (17.3 +/- 3 vs 53.8 +/- 6.6 microg/dL, 190.5 +/- 15 vs 287.9 +/- 14.3 mg/dL and 7.7 +/- 1.3 vs 15.4 +/- 1.6%, P 1.5 vs 0.7 +/- 0.2 mg/dL, P = 0.016 and P 2 years), the observed differences persisted. Hyposideraemia is a frequent finding in the acute phase of paediatric burns and is accompanied by increased ferritin levels and decreased transferrin concentrations. The low iron values tend to recover without the use of iron supplementation suggesting an endogenous block of iron release in the acute phase and indicates that iron therapy should be not recommended in the initial period of stress of the burned patient.

  16. Environmental association of iron minerals and iron concentrations ...

    African Journals Online (AJOL)

    DR. MIKE HORSFALL

    Iron minerals namely hematite and goethite were found in soils from the study area but only ... The use of multivariate analyses in understanding different physical ..... Analyzing Plant Tissue Samples, In; Soil Testing and. Plant Analysis, 3rd Ed.

  17. Bioavailability of iron speciations and EDTA-iron complexes for ...

    African Journals Online (AJOL)

    Selin

    2012-01-19

    Jan 19, 2012 ... extraction in 90% acetone and held at 4°C, 24 h in the dark. Parsons ..... Confirmation of iron limitation of phytoplankton photosynthesis in the equatorial .... determination of marine plant pigments, with revised equations for.

  18. [Phosphate metabolism and iron deficiency].

    Science.gov (United States)

    Yokoyama, Keitaro

    2016-02-01

    Autosomal dominant hypophosphatemic rickets(ADHR)is caused by gain-of-function mutations in FGF23 that prevent its proteolytic cleavage. Fibroblast growth factor 23(FGF23)is a hormone that inhibits renal phosphate reabsorption and 1,25-dihydroxyvitamin D biosynthesis. Low iron status plays a role in the pathophysiology of ADHR. Iron deficiency is an environmental trigger that stimulates FGF23 expression and hypophosphatemia in ADHR. It was reported that FGF23 elevation in patients with CKD, who are often iron deficient. In patients with nondialysis-dependent CKD, treatment with ferric citrate hydrate resulted in significant reductions in serum phosphate and FGF23.

  19. Austempered ductile iron process development

    Science.gov (United States)

    Gupta, C. D.; Keough, J. R.; Pramstaller, D. M.

    1986-11-01

    Pressure from imports and material substitution has severly affected demand for domestic iron industry products. It is estimated that the potential market for Austempered Ductile Iron (ADI) is as large as the market for carburized and/or through hardened forgings. The primary interest in ADI is generated by the economics of process. Improved machinability and reduced processing costs as well as interesting physical properties has created an enormous interest in all metalworking industries towards ADI. The development of gas-fired austempering processes and resoluton of technical and economic uncertainities concerning the process will help improve the outlook for iron founderies.

  20. Technology of Iron Carbide Synthesis

    Institute of Scientific and Technical Information of China (English)

    M.Bahgat

    2006-01-01

    Iron carbides are very promising metallurgical products and can be used for steelmaking process, where it plays as an alternative raw material with significant economic advantages. Also it has many other applications,e.g. catalysts, magnets, sensors. The present review investigates the different properties and uses of the iron carbides. The commercial production and the different varieties for the iron carbides synthesis (gaseous carburization, mechanochemical synthesis, laser pyrolysis, plasma pyrolysis, chemical vapor deposition and ion implantation) were reviewed. Also the effect of different factors on the carburization process like gas composition, raw material, temperature, reaction time, catalyst presence and sulfur addition was indicated.

  1. Magnetic study of iron sorbitol

    Energy Technology Data Exchange (ETDEWEB)

    Lazaro, F.J. E-mail: osoro@posta.unizar.es; Larrea, A.; Abadia, A.R.; Romero, M.S

    2002-09-01

    A magnetic study of iron sorbitol, an iron-containing drug to treat the iron deficiency anemia is presented. Transmission electron microscopy reveals that the system contains nanometric particles with an average diameter of 3 nm whose composition is close to two-line ferrihydrite. The characterisation by magnetisation and AC susceptibility measurements indicates superparamagnetic behaviour with progressive magnetic blocking starting at 8 K. The quantitative analysis of the magnetic results indicates that the system consists of an assembly of very small magnetic moments, presumably originated by spin uncompensation of the antiferromagnetic nanoparticles, with Arrhenius type magnetic dynamics.

  2. 21 CFR 522.1182 - Iron injection.

    Science.gov (United States)

    2010-04-01

    ... equivalent of: (1) 100 milligrams (mg) of elemental iron derived from: (i) Ferric hydroxide; (ii) Ferric oxide; or (iii) Elemental iron. (2) 200 mg of elemental iron derived from ferric hydroxide. (b) Sponsors... 21 Food and Drugs 6 2010-04-01 2010-04-01 false Iron injection. 522.1182 Section 522.1182 Food...

  3. Iron incorporation and post-malaria anaemia

    Science.gov (United States)

    Iron supplementation is employed to treat post-malarial anaemia in environments where iron deficiency is common. Malaria induces an intense inflammatory reaction that stalls reticulo-endothelial macrophagal iron recycling from haemolysed red blood cells and inhibits oral iron absorption, but the mag...

  4. Hydrolysis of soybean protein improves iron bioavailability

    Science.gov (United States)

    Iron is an important trace metal element in human body. Iron deficiency affects human health, especially pregnant women and children. Soybean protein is a popular food in Asia and can contain a high amount of iron (145.70±0.74 ug/g); however, it is usually reported as an inhibitor of iron absorption...

  5. Iron excess in recreational marathon runners

    NARCIS (Netherlands)

    Mettler, S.; Zimmermann, M.B.

    2010-01-01

    Background/Objectives: Iron deficiency and anemia may impair athletic performance, and iron supplements are commonly consumed by athletes. However, iron overload should be avoided because of the possible long-term adverse health effects. Methods: We investigated the iron status of 170 male and

  6. Placental iron uptake and its regulation

    NARCIS (Netherlands)

    M. Bierings (Marc)

    1989-01-01

    textabstractIron transport in pregnancy is an active one-way process, from mother to fetus. Early in gestation fetal iron needs are low, and so is trans-placental transport, but as erythropoiesis develops, rising fetal iron needs are met by trans-placental iron transport. Apparently, the fetus is pr

  7. Iron excess in recreational marathon runners

    NARCIS (Netherlands)

    Mettler, S.; Zimmermann, M.B.

    2010-01-01

    Background/Objectives: Iron deficiency and anemia may impair athletic performance, and iron supplements are commonly consumed by athletes. However, iron overload should be avoided because of the possible long-term adverse health effects. Methods: We investigated the iron status of 170 male and femal

  8. Reductive iron assimilation and intracellular siderophores assist extracellular siderophore-driven iron homeostasis and virulence

    Science.gov (United States)

    Iron is an essential nutrient and prudent iron acquisition and management are key traits of a successful pathogen. Fungi use nonribosomally synthesized secreted iron chelators (siderophores) or Reductive Iron Assimilation (RIA) mechanisms to acquire iron in a high affinity manner. Previous studies...

  9. Iron deficiency anemia in heart failure.

    Science.gov (United States)

    Arora, Natasha P; Ghali, Jalal K

    2013-07-01

    Anemia and iron deficiency are quite prevalent in patients with heart failure (HF) and may overlap. Both anemia and iron deficiency are associated with worse symptoms and adverse clinical outcomes. In the past few years, there has been an enormous interest in the subject of iron deficiency and its management in patients with HF. In this review, the etiology and relevance of iron deficiency, iron metabolism in the setting of HF, studies on iron supplementation in patients with HF and potential cardiovascular effects of subclinical iron overload are discussed.

  10. Emission Inventory for Fugitive Emissions in Denmark

    DEFF Research Database (Denmark)

    Plejdrup, Marlene Schmidt; Nielsen, Ole-Kenneth; Nielsen, Malene

    This report presents the methodology and data used in the Danish inventory of fugitive emissions from fuels for the years until 2007. The inventory of fugitive emissions includes CO2, CH4, N2O, NOx, CO, NMVOC, SO2, dioxin, PAH and particulate matter. In 2007 the total Danish emission of greenhouse...

  11. Directly observed iron supplementation for control of iron deficiency anemia

    Directory of Open Access Journals (Sweden)

    Mohan Bairwa

    2017-01-01

    Full Text Available Anemia is major public health problem affecting 1.6 billion people worldwide. The poor compliance of iron supplementation remains main contributor for high prevalence of anemia. The current paper reviewed the effectiveness of direct observation of oral iron supplementation on anemia. A systematic search was performed through electronic databases and local libraries. Search strategies used subject headings and key words “directly observed” and “iron supplementation.” Searches were sought through April 2014. A total of 14 articles were included in the study. Findings were presented in three categories. First, all of those reported an improvement in compliance of iron supplementation. Second, reduction in the prevalence of anemia was reported by all and third, all except one reported increased blood hemoglobin level. Directly observed an iron supplementation is an effective approach for prevention and management of anemia in vulnerable groups. However, larger trials are needed before concluding that scaling up directly observed iron supplementation through community health volunteers would be beneficial.

  12. Iron metabolism in the mononuclear phagocyte system

    Institute of Scientific and Technical Information of China (English)

    Weina Kong; Xianglin Duan; Zhenhua Shi; Yanzhong Chang

    2008-01-01

    The maintenance of body iron homeostasis requires the coordination of multiple regulatory mechanisms of iron metabolism.The mononuclear phagocyte system (MPS,composed of monocytes,macrophages,and their precursor cells) is crucial in the maintenance of iron homeostasis.Recycling of iron is carried out by specialized macrophages via engulfment of aged erythrocytes.The iron stores of macrophages depend on the levels of recovered and exported iron.However,the molecular mechanisms underlying iron homeostasis in macrophages are poorly understood.Recent studies characterizing the function and regulation of natural resistance-associated macrophage protein 1 (Nrampl),divalent metal transporter 1 (DMTI),HLA-linked hemechromatosis gene (HFE),ferroportin 1 (FPN1),and hepcidin are rapidly expanding our knowledge on the molecular level of MPS iron handling.These studies are deepening our understanding about the molecular mechanism of iron homeostasis and iron-related diseases.

  13. IRON-TOLERANT CYANOBACTERIA: IMPLICATIONS FOR ASTROBIOLOGY

    Science.gov (United States)

    Brown, Igor I.; Allen, Carlton C.; Mummey, Daniel L.; Sarkisova, Svetlana A.; McKay, David S.

    2006-01-01

    The review is dedicated to the new group of extremophiles - iron tolerant cyanobacteria. The authors have analyzed earlier published articles about the ecology of iron tolerant cyanobacteria and their diversity. It was concluded that contemporary iron depositing hot springs might be considered as relative analogs of Precambrian environment. The authors have concluded that the diversity of iron-tolerant cyanobacteria is understudied. The authors also analyzed published data about the physiological peculiarities of iron tolerant cyanobacteria. They made the conclusion that iron tolerant cyanobacteria may oxidize reduced iron through the photosystem of cyanobacteria. The involvement of both Reaction Centers 1 and 2 is also discussed. The conclusion that iron tolerant protocyanobacteria could be involved in banded iron formations generation is also proposed. The possible mechanism of the transition from an oxygenic photosynthesis to an oxygenic one is also discussed. In the final part of the review the authors consider the possible implications of iron tolerant cyanobacteria for astrobiology.

  14. Characteristic x-ray emission from undermines plasmas irradiated by ultra-intense lasers

    Energy Technology Data Exchange (ETDEWEB)

    Niemann, Christoph [Univ. of California, Los Angeles, CA (United States)

    2012-05-05

    Between FY09 and FY11 we have conducted more than a dozen three-week experimental campaigns at high-power laser facilities around the world to investigate laser-channeling through x-ray and optical imaging and the conversion from laser-energy to xrays. We have performed simultaneous two-wavelength x-ray imaging (K-alpha and He-alpha) to distinguish the hot-plasma region (hot-spot) from the laser-produced electrons (K-alpha). In addition, we have initiated a new collaboration with SNL and have performed first shots on the 100 TW beamlet chamber to commission a fast x-ray streak camera to be used to investigate the temporal evolution of our K-alpha sources. We also collaborated on campaigns at the Rutherford Appleton Laboratory (UK) and the LANL Trident laser to employ laser produced x-ray sources for Thomson scattering off dense matter.

  15. A pilot-scale study of selective desulfurization via urea addition in iron ore sintering

    Science.gov (United States)

    Long, Hong-ming; Wu, Xue-jian; Chun, Tie-jun; Di, Zhan-xia; Wang, Ping; Meng, Qing-min

    2016-11-01

    The iron ore sintering process is the main source of SO2 emissions in the iron and steel industry. In our previous research, we proposed a novel technology for reducing SO2 emissions in the flue gas in the iron ore sintering process by adding urea at a given distance from the sintering grate bar. In this paper, a pilot-scale experiment was carried out in a commercial sintering plant. The results showed that, compared to the SO2 concentration in flue gas without urea addition, the SO2 concentration decreased substantially from 694.2 to 108.0 mg/m3 when 0.10wt% urea was added. NH3 decomposed by urea reacted with SO2 to produce (NH4)2SO4, decreasing the SO2 concentration in the flue gas.

  16. Harmful admixtures assessment in sinter mixtures used in iron ore sinter plants in Poland

    Directory of Open Access Journals (Sweden)

    J. Korol

    2014-10-01

    Full Text Available In this study composition of sinter mixtures used in Polish sinter plants were established. Seven sinter mixtures composition were examined, based on iron-bearing materials, admixtures and fuels. Contents of harmful admixtures were examined according to three kinds of environmental impacts: emissions of SOx, heavy metals, polychlorinated dibenzodioxins and polychlorinated dibenzofurans (PCDDs/PCDFs.

  17. Energy Intensity Development of the German Iron and Steel Industry between 1991 and 2007

    NARCIS (Netherlands)

    Arens, M.; Worrell, E.; Schleich, J.

    2012-01-01

    The iron and steel sector is the largest industrial CO2 emitter and energy consumer in the world. Energy efficiency is key to reduce energy consumption and GHG emissions. To understand future developments of energy use in the steel sector, it is worthwhile to analyze energy efficiency developments o

  18. Hyperferritinaemia in the absence of iron overload

    OpenAIRE

    Arnold, J.; Mumford, A.; Lindsay, J; Hegde, U; Hagan, M; Hawkins, J.

    1997-01-01

    Background—Serum ferritin is normally a marker of iron overload. Ferritin genes are sited at chromosomes 19 and 11. Regulation of ferritin synthesis involves an interaction between an iron regulatory protein (IRP) and part of the ferritin mRNA designated the iron regulatory element (IRE). A disorder of ferritin synthesis resulting in hyperferritinaemia in the absence of iron overload has been described recently. 
Patients and methods—Hyperferriti- naemia in the absence of iron ove...

  19. Targeting Iron Deficiency Anemia in Heart Failure.

    Science.gov (United States)

    Saraon, Tajinderpal; Katz, Stuart D

    2016-01-01

    Iron deficiency is common in heart failure (HF) patients, and is associated with increased risk of adverse clinical outcomes. Clinical trials of intravenous iron supplementation in iron-deficient HF patients have demonstrated short-term improvement in functional capacity and quality of life. In some trials, the benefits of iron supplementation were independent of the hemoglobin levels. Additional investigations of iron supplementation are needed to characterize the mechanisms contributing to clinical benefit and long-term safety in HF.

  20. The Pharmacokinetics and Pharmacodynamics of Iron Preparations

    OpenAIRE

    Susanna Burckhardt; Peter Geisser

    2011-01-01

    Standard approaches are not appropriate when assessing pharmacokinetics of iron supplements due to the ubiquity of endogenous iron, its compartmentalized sites of action, and the complexity of the iron metabolism. The primary site of action of iron is the erythrocyte, and, in contrast to conventional drugs, no drug-receptor interaction takes place. Notably, the process of erythropoiesis, i.e., formation of new erythrocytes, takes 3−4 weeks. Accordingly, serum iron concentration and area under...

  1. Iron pnictide superconductors

    Energy Technology Data Exchange (ETDEWEB)

    Tegel, Marcus Christian

    2011-03-22

    The scope of this dissertation therefore has not only been the synthesis of various new superconducting and non-superconducting iron pnictides of several structural families but also their in-depth crystallographic and physical characterisation. In Chapters 3 - 6, the family of the ZrCuSiAs-type (1111) compounds is subject of discussion. The solid solution series La(Co{sub x}Fe{sub 1-x})PO is analysed regarding magnetic and superconducting properties and the new compounds EuMnPF and REZnPO, as well as the new superconductor parent compound SrFeAsF are presented. Chapters 7 - 9 are dedicated to the new iron arsenide superconductors of the ThCr{sub 2}Si{sub 2}-type (122 family). Therein, also the discovery of the first superconductor in this structural family, Ba{sub 0.6}K{sub 0.4}Fe{sub 2}As{sub 2}, is unveiled. A detailed examination of the complete solid solution series (Ba{sub 1-x}K{sub x})Fe{sub 2}As{sub 2} is presented. Moreover, the crystallographic phase transitions of the closely related compounds SrFe{sub 2}As{sub 2} and EuFe{sub 2}As{sub 2} are characterised and the superconductors Sr{sub 1-x}K{sub x}Fe{sub 2}As{sub 2} and Ca{sub 1-x}Na{sub x}Fe{sub 2}As{sub 2} are examined for magnetic and phononic excitations. In Chapter 10, the redetermined crystal structure of the superconductor Fe(Se{sub 1-x}Te{sub x}) (11-type) is presented from a chemist's point of view. Chapters 11 - 14 look into the superconducting and non-superconducting iron arsenides of more complex structural families (32522-type and 21311-type). Therein, crystallographic and magnetic details of Sr{sub 3}Sc{sub 2}O{sub 5}Fe{sub 2}As{sub 2} are presented and Ba{sub 2}ScO{sub 3}FeAs and Sr{sub 2}CrO{sub 3}FeAs, the first two members of the new 21311-type are portrayed. Sr{sub 2}CrO{sub 3}FeAs is looked at in close detail with various methods, so e.g. the spin structure of the magnetically ordered compound is solved and a possible reason for the absence of superconductivity in this compound

  2. Simulated changes in dissolved Iron deposition to the global ocean driven by human activity

    Science.gov (United States)

    Myriokefalitakis, Stelios; Daskalakis, Nikos; Mihalopoulos, Nikos; Baker, Alex R.; Nenes, Athanassios; Kanakidou, Maria

    2015-04-01

    The global 3-d chemistry transport atmospheric model TM4-ECPL is used to simulate the atmospheric cycle of iron (Fe) and evaluate its atmospheric deposition to the ocean by accounting for both Fe natural and anthropogenic sources as well as of the proton and ligand promoted iron mobilisation from dust aerosol. Model evaluation is performed by comparison to available observations. Present day dissolved Fe deposition presents strong spatial and temporal variability with an annual deposition flux about 0.489 Tg(Fe)/yr from which about 25% are deposited over the ocean. The model simulates past, present and future iron deposition accounting for changes in anthropogenic emissions. We show that dissolved iron deposition has significantly increased since 1850 while it is expected to decrease in the future due to air pollution regulations. These changes affect the atmospheric dissolved Fe supply to High-Nutrient-Low-Chlorophyll oceanic areas characterized by Fe scarcity.

  3. N-butylamine functionalized graphene oxide for detection of iron(III) by photoluminescence quenching.

    Science.gov (United States)

    Gholami, Javad; Manteghian, Mehrdad; Badiei, Alireza; Ueda, Hiroshi; Javanbakht, Mehran

    2016-02-01

    An N-butylamine functionalized graphene oxide nanolayer was synthesized and characterized by ultraviolet (UV)-visible spectrometry, Fourier transform infrared spectroscopy, X-ray photoelectron spectroscopy, and transmission electron microscopy. Detection of iron(III) based on photoluminescence spectroscopy was investigated. The N-butylamine functionalized graphene oxide was shown to specifically interact with iron (III), compared with other cationic trace elements including potassium (I), sodium (I), calcium (II), chromium (III), zinc (II), cobalt (II), copper (II), magnesium (II), manganese (II), and molybdenum (VI). The quenching effect of iron (III) on the luminescence emission of N-butylamine functionalized graphene oxide layer was used to detect iron (III). The limit of detection (2.8 × 10(-6)  M) and limit of quantitation (2.9 × 10(-5)  M) were obtained under optimal conditions.

  4. Effects of engineered iron nanoparticles on the bryophyte, Physcomitrella patens (Hedw.) Bruch & Schimp, after foliar exposure.

    Science.gov (United States)

    Canivet, L; Dubot, P; Garçon, G; Denayer, F-O

    2015-03-01

    The effects of iron nanoparticles on bryophytes (Physcomitrella patens) were studied following foliar exposure. We used iron nanoparticles (Fe-NP) representative of industrial emissions from the metallurgical industries. After a characterization of iron nanoparticles and the validation of nanoparticle internalization in cells, the effects (cytotoxicity, oxidative stress, lipid peroxidation of membrane) of iron nanoparticles were determined through the axenic culturing of Physcomitrella patens exposed at five different concentrations (5 ng, 50 ng, 500 ng, 5 µg and 50 µg per plant). Following exposure, the plant health, measured as ATP concentrations, was not impacted. Moreover, we studied oxidative stress in three ways: through the measure of reactive oxygen species (ROS) production, through malondialdehyde (MDA) production and also through glutathione regulation. At concentrations tested over a short period, the level of ROS, MDA and glutathione were not significantly disturbed.

  5. Biofuel-Promoted Polychlorinated Dibenzodioxin/furan Formation in an Iron-Catalyzed Diesel Particle Filter.

    Science.gov (United States)

    Heeb, Norbert V; Rey, Maria Dolores; Zennegg, Markus; Haag, Regula; Wichser, Adrian; Schmid, Peter; Seiler, Cornelia; Honegger, Peter; Zeyer, Kerstin; Mohn, Joachim; Bürki, Samuel; Zimmerli, Yan; Czerwinski, Jan; Mayer, Andreas

    2015-08-04

    Iron-catalyzed diesel particle filters (DPFs) are widely used for particle abatement. Active catalyst particles, so-called fuel-borne catalysts (FBCs), are formed in situ, in the engine, when combusting precursors, which were premixed with the fuel. The obtained iron oxide particles catalyze soot oxidation in filters. Iron-catalyzed DPFs are considered as safe with respect to their potential to form polychlorinated dibenzodioxins/furans (PCDD/Fs). We reported that a bimetallic potassium/iron FBC supported an intense PCDD/F formation in a DPF. Here, we discuss the impact of fatty acid methyl ester (FAME) biofuel on PCDD/F emissions. The iron-catalyzed DPF indeed supported a PCDD/F formation with biofuel but remained inactive with petroleum-derived diesel fuel. PCDD/F emissions (I-TEQ) increased 23-fold when comparing biofuel and diesel data. Emissions of 2,3,7,8-TCDD, the most toxic congener [toxicity equivalence factor (TEF) = 1.0], increased 90-fold, and those of 2,3,7,8-TCDF (TEF = 0.1) increased 170-fold. Congener patterns also changed, indicating a preferential formation of tetra- and penta-chlorodibenzofurans. Thus, an inactive iron-catalyzed DPF becomes active, supporting a PCDD/F formation, when operated with biofuel containing impurities of potassium. Alkali metals are inherent constituents of biofuels. According to the current European Union (EU) legislation, levels of 5 μg/g are accepted. We conclude that risks for a secondary PCDD/F formation in iron-catalyzed DPFs increase when combusting potassium-containing biofuels.

  6. Streamlining Iron and Steel Production

    Institute of Scientific and Technical Information of China (English)

    2008-01-01

    Eliminating unproductive iron and steel facilities is vital to environmental protection and sustainable development of this industry The Chinese Government is once again shutting down unproductive plants in tune with its green policy and the march toward sustainable development.This time it’s the iron and steel industry to feel the brunt of the Chinese Government’s stringent measures. The deafening buzz of factory floors have

  7. Iron deficiency and cognitive functions

    OpenAIRE

    Jáuregui-Lobera I

    2014-01-01

    Ignacio Jáuregui-Lobera Department of Nutrition and Bromatology, Pablo de Olavide University, Seville, Spain Abstract: Micronutrient deficiencies, especially those related to iodine and iron, are linked to different cognitive impairments, as well as to potential long-term behavioral changes. Among the cognitive impairments caused by iron deficiency, those referring to attention span, intelligence, and sensory perception functions are mainly cited, as well as those associated with...

  8. Iron deficiency and cognitive functions

    OpenAIRE

    Jáuregui-Lobera I

    2014-01-01

    Ignacio Jáuregui-Lobera Department of Nutrition and Bromatology, Pablo de Olavide University, Seville, Spain Abstract: Micronutrient deficiencies, especially those related to iodine and iron, are linked to different cognitive impairments, as well as to potential long-term behavioral changes. Among the cognitive impairments caused by iron deficiency, those referring to attention span, intelligence, and sensory perception functions are mainly cited, as well as those associated with...

  9. Iron, Oxidative Stress and Gestational Diabetes

    Directory of Open Access Journals (Sweden)

    Taifeng Zhuang

    2014-09-01

    Full Text Available Both iron deficiency and hyperglycemia are highly prevalent globally for pregnant women. Iron supplementation is recommended during pregnancy to control iron deficiency. The purposes of the review are to assess the oxidative effects of iron supplementation and the potential relationship between iron nutrition and gestational diabetes. High doses of iron (~relative to 60 mg or more daily for adult humans can induce lipid peroxidation in vitro and in animal studies. Pharmaceutical doses of iron supplements (e.g., 10× RDA or more for oral supplements or direct iron supplementation via injection or addition to the cell culture medium for a short or long duration will induce DNA damage. Higher heme-iron intake or iron status measured by various biomarkers, especially serum ferritin, might contribute to greater risk of gestational diabetes, which may be mediated by iron oxidative stress though lipid oxidation and/or DNA damage. However, information is lacking about the effect of low dose iron supplementation (≤60 mg daily on lipid peroxidation, DNA damage and gestational diabetes. Randomized trials of low-dose iron supplementation (≤60 mg daily for pregnant women are warranted to test the relationship between iron oxidative stress and insulin resistance/gestational diabetes, especially for iron-replete women.

  10. [Iron metabolism, overview and recent insights].

    Science.gov (United States)

    Omar, S; Feki, M; Kaabachi, N

    2006-01-01

    The paper is an up to date overview of knowledge on iron metabolism that integrate recent findings in this field. Significant advances were made in understanding the implication of protein factors (transporters, enzymes and regulation factors) in iron metabolism, as well as related genetic abnormalities. The research highlighted the complexity of mechanisms in charge of maintaining equilibrium of Fe in the body. The iron is vital to the life of cells, but its presence in excess is rather toxic. Iron is mostly required for hemoglobin synthesis. It is recycled between reticulo-endothelial macrophages and bone marrow that is the main user of iron. Intestinal absorption is a key step in determining iron capital in the body. Its rate is tightly controlled by several factors that act under influence of signals of unknown nature, which indicate iron needs and storage. The IRP/IRE (iron regulatory protein/iron responsive element) system controls cellular uptake, stores and exportation of iron, and heme synthesis. Mitochondrion is a dynamo of iron metabolism, being vital for heme synthesis and iron sulphur cluster genesis. The recent discovery of several mitochondrial proteins involved in iron metabolism resulted in better understanding mitochondrial iron movement, storage and exchange. Nevertheless, much remains to be known on the role of some actors such as HFE protein, hepcidin, hemojuvelin and transferrin receptor 2, and to determine the nature and mechanisms of signals regulating iron level in the body.

  11. Maximum stellar iron core mass

    Indian Academy of Sciences (India)

    F W Giacobbe

    2003-03-01

    An analytical method of estimating the mass of a stellar iron core, just prior to core collapse, is described in this paper. The method employed depends, in part, upon an estimate of the true relativistic mass increase experienced by electrons within a highly compressed iron core, just prior to core collapse, and is significantly different from a more typical Chandrasekhar mass limit approach. This technique produced a maximum stellar iron core mass value of 2.69 × 1030 kg (1.35 solar masses). This mass value is very near to the typical mass values found for neutron stars in a recent survey of actual neutron star masses. Although slightly lower and higher neutron star masses may also be found, lower mass neutron stars are believed to be formed as a result of enhanced iron core compression due to the weight of non-ferrous matter overlying the iron cores within large stars. And, higher mass neutron stars are likely to be formed as a result of fallback or accretion of additional matter after an initial collapse event involving an iron core having a mass no greater than 2.69 × 1030 kg.

  12. Ferritins: furnishing proteins with iron.

    Science.gov (United States)

    Bradley, Justin M; Le Brun, Nick E; Moore, Geoffrey R

    2016-03-01

    Ferritins are a superfamily of iron oxidation, storage and mineralization proteins found throughout the animal, plant, and microbial kingdoms. The majority of ferritins consist of 24 subunits that individually fold into 4-α-helix bundles and assemble in a highly symmetric manner to form an approximately spherical protein coat around a central cavity into which an iron-containing mineral can be formed. Channels through the coat at inter-subunit contact points facilitate passage of iron ions to and from the central cavity, and intrasubunit catalytic sites, called ferroxidase centers, drive Fe(2+) oxidation and O2 reduction. Though the different members of the superfamily share a common structure, there is often little amino acid sequence identity between them. Even where there is a high degree of sequence identity between two ferritins there can be major differences in how the proteins handle iron. In this review we describe some of the important structural features of ferritins and their mineralized iron cores, consider how iron might be released from ferritins, and examine in detail how three selected ferritins oxidise Fe(2+) to explore the mechanistic variations that exist amongst ferritins. We suggest that the mechanistic differences reflect differing evolutionary pressures on amino acid sequences, and that these differing pressures are a consequence of different primary functions for different ferritins.

  13. Management of Iron Deficiency Anemia

    Science.gov (United States)

    Jimenez, Kristine; Kulnigg-Dabsch, Stefanie

    2015-01-01

    Anemia affects one-fourth of the world’s population, and iron deficiency is the predominant cause. Anemia is associated with chronic fatigue, impaired cognitive function, and diminished well-being. Patients with iron deficiency anemia of unknown etiology are frequently referred to a gastroenterologist because in the majority of cases the condition has a gastrointestinal origin. Proper management improves quality of life, alleviates the symptoms of iron deficiency, and reduces the need for blood transfusions. Treatment options include oral and intravenous iron therapy; however, the efficacy of oral iron is limited in certain gastrointestinal conditions, such as inflammatory bowel disease, celiac disease, and autoimmune gastritis. This article provides a critical summary of the diagnosis and treatment of iron deficiency anemia. In addition, it includes a management algorithm that can help the clinician determine which patients are in need of further gastrointestinal evaluation. This facilitates the identification and treatment of the underlying condition and avoids the unnecessary use of invasive methods and their associated risks. PMID:27099596

  14. [Genetics of hereditary iron overload].

    Science.gov (United States)

    Le Gall, Jean-Yves; Jouanolle, Anne-Marie; Fergelot, Patricia; Mosser, Jean; David, Véronique

    2004-01-01

    The classification of hereditary abnormalities of iron metabolism was recently expanded and diversified. Genetic hemochromatosis now corresponds to six diseases, namely classical hemochromatosis HFE 1; juvenile hemochromatosis HFE 2 due to mutations in an unidentified gene on chromosome 1; hemochromatosis HFE 3 due to mutations in the transferrin receptor 2 (TfR2); hemochromatosis HFE 4 caused by a mutation in the H subunit of ferritin; and hemochromatosis HFE 6 whose gene is hepcidine (HAMP). Systemic iron overload is also associated with aceruloplasminemia, atransferrinemia and the "Gracile" syndrome caused by mutations in BCS1L. The genes responsible for neonatal and African forms of iron overload are unknown. Other genetic diseases are due to localized iron overload: Friedreich's ataxia results from the expansion of triple nucleotide repeats within the frataxin (FRDA) gene; two forms of X-linked sideroblastic anemia are due to mutations within the delta aminolevulinate synthetase (ALAS 2) or ABC-7 genes; Hallervorden-Spatz syndrome is caused by a pantothenate kinase 2 gene (PANK-2) defect; neuroferritinopathies; and hyperferritinemia--cataract syndrome due to a mutation within the L-ferritin gene. In addition to this wide range of genetic abnormalities, two other features characterize these iron disorders: 1) most are transmitted by an autosomal recessive mechanism, but some, including hemochromatosis type 4, have dominant transmission; and 2) most correspond to cytosolic iron accumulation while some, like Friedreich's ataxia, are disorders of mitochondrial metabolism.

  15. Mössbauer characterisation of Fe-polygalacturonate as a medicine for human anaemia: the effect of iron concentration

    Science.gov (United States)

    Fodor, Judit; Kuzmann, Ernő; Vértes, Attila; Homonnay, Zoltán; Klencsár, Zoltán; May, Zoltán; Szentmihályi, Klára

    2009-04-01

    57Fe Mössbauer spectroscopy was used to study the effect of iron concentration on the oxidation state and microenvironments of iron in Fe-polygalacturonate compounds prepared by a novel method from pectin. The iron concentration of the coordination compounds was determined by inductively coupled plasma optical emission spectrometry analysis. The Mössbauer spectra of the studied compounds could be decomposed into three markedly different quadrupole doublets referring to three microenvironments. Two of these have ferrous and one has ferric oxidation state. In the applied concentration range the relative occurrence of the ferric component was found to increase considerably with iron concentration. At the same time, with increasing iron concentration the relative occurrence characteristic of the three components showed saturation behaviour up to the iron concentration at which for each pair of galacturonic acid units there is on average one iron atom in the system, which iron concentration value is interpreted as to be related to the complete fill up of certain iron complexation sites of the polygalacturonate chains.

  16. Moessbauer characterisation of Fe-polygalacturonate as a medicine for human anaemia: the effect of iron concentration

    Energy Technology Data Exchange (ETDEWEB)

    Fodor, Judit, E-mail: fodorj@chemres.hu [Hungarian Academy of Sciences, Institute of Materials and Environmental Chemistry, Chemical Research Center (Hungary); Kuzmann, Erno [Hungarian Academy of Sciences, Department of Nuclear Chemistry, Institute of Nanochemistry and Catalysis, Chemical Research Center (Hungary); Vertes, Attila; Homonnay, Zoltan [Eoetvoes Lorand University, Institute of Chemistry (Hungary); Klencsar, Zoltan [Hungarian Academy of Sciences, Department of Surface Modifications and Nanostructures, Institute of Nanochemistry and Catalysis, Chemical Research Center (Hungary); May, Zoltan; Szentmihalyi, Klara [Hungarian Academy of Sciences, Institute of Materials and Environmental Chemistry, Chemical Research Center (Hungary)

    2009-04-15

    {sup 57}Fe Moessbauer spectroscopy was used to study the effect of iron concentration on the oxidation state and microenvironments of iron in Fe-polygalacturonate compounds prepared by a novel method from pectin. The iron concentration of the coordination compounds was determined by inductively coupled plasma optical emission spectrometry analysis. The Moessbauer spectra of the studied compounds could be decomposed into three markedly different quadrupole doublets referring to three microenvironments. Two of these have ferrous and one has ferric oxidation state. In the applied concentration range the relative occurrence of the ferric component was found to increase considerably with iron concentration. At the same time, with increasing iron concentration the relative occurrence characteristic of the three components showed saturation behaviour up to the iron concentration at which for each pair of galacturonic acid units there is on average one iron atom in the system, which iron concentration value is interpreted as to be related to the complete fill up of certain iron complexation sites of the polygalacturonate chains.

  17. In vitro bioavailability of iron from the heme analogue sodium iron chlorophyllin.

    Science.gov (United States)

    Miret, Silvia; Tascioglu, Serpil; van der Burg, Monique; Frenken, Leon; Klaffke, Werner

    2010-01-27

    The use of heme analogues from vegetable origin could provide an alternative iron source of potentially high bioavailability. Sodium iron chlorophyllin is a water-soluble semisynthetic chlorophyll derivative where the magnesium in the porphyrin ring has been substituted by iron. We have used an in vitro model that combines gastric and intestinal digestion followed by intestinal iron uptake in Caco-2 cells to determine the bioavailability of iron from sodium iron chlorophyllin. Our results demonstrate that sodium iron chlorophyllin is stable under simulated gastrointestinal conditions and is able to deliver bioavailable iron to Caco-2 cells. Similar to the heme, the bioavailability of iron from sodium iron chlorophyllin is dependent on the food matrix, and it was inhibited by calcium. Potentially, sodium iron chlorophyllin could be used as an iron fortificant from vegetable origin with high bioavailability.

  18. Host iron status and iron supplementation mediate susceptibility to erythrocytic stage Plasmodium falciparum.

    Science.gov (United States)

    Clark, Martha A; Goheen, Morgan M; Fulford, Anthony; Prentice, Andrew M; Elnagheeb, Marwa A; Patel, Jaymin; Fisher, Nancy; Taylor, Steve M; Kasthuri, Raj S; Cerami, Carla

    2014-07-25

    Iron deficiency and malaria have similar global distributions, and frequently co-exist in pregnant women and young children. Where both conditions are prevalent, iron supplementation is complicated by observations that iron deficiency anaemia protects against falciparum malaria, and that iron supplements increase susceptibility to clinically significant malaria, but the mechanisms remain obscure. Here, using an in vitro parasite culture system with erythrocytes from iron-deficient and replete human donors, we demonstrate that Plasmodium falciparum infects iron-deficient erythrocytes less efficiently. In addition, owing to merozoite preference for young erythrocytes, iron supplementation of iron-deficient individuals reverses the protective effects of iron deficiency. Our results provide experimental validation of field observations reporting protective effects of iron deficiency and harmful effects of iron administration on human malaria susceptibility. Because recovery from anaemia requires transient reticulocytosis, our findings imply that in malarious regions iron supplementation should be accompanied by effective measures to prevent falciparum malaria.

  19. Effects of Iron Limitation on Photosystem II Composition and Light Utilization in Dunaliella tertiolecta.

    Science.gov (United States)

    Vassiliev, I. R.; Kolber, Z.; Wyman, K. D.; Mauzerall, D.; Shukla, V. K.; Falkowski, P. G.

    1995-11-01

    The effects of iron limitation on photosystem II (PSII) composition and photochemical energy conversion efficiency were studied in the unicellular chlorophyte alga Dunaliella tertiolecta. The quantum yield of photochemistry in PSII, inferred from changes in variable fluorescence normalized to the maximum fluorescence yield, was markedly lower in iron-limited cells and increased 3-fold within 20 h following the addition of iron. The decrease in the quantum yield of photochemistry was correlated with increased fluorescence emission from the antenna. In iron-limited cells, flash intensity saturation profiles of variable fluorescence closely followed a cumulative one-hit Poisson model, suggesting that PSII reaction centers are energetically isolated, whereas in iron-replete cells, the slope of the profile was steeper and the calculated probability of energy transfer between reaction centers increased to >0.6. Immunoassays revealed that in iron-limited cells the reaction center proteins, D1, CP43, and CP47, were markedly reduced relative to the peripheral light-harvesting Chl-protein complex of PSII, whereas the [alpha] subunit of cytochrome b559 was about 10-fold higher. Spectroscopic analysis established that the cytochrome b559 peptide did not contain an associated functional heme. We conclude that the photochemical conversion of absorbed excitation energy in iron-limited cells is limited by the number of photochemical traps per unit antenna.

  20. Iron Abundance Diagnostics in High-Redshift QSOs

    CERN Document Server

    Corbin, M R; Freduling, N K W; Corbin, Michael R.; Korista, Kirk T.; Freduling, Nalaka Kodituwakku & Wolfram

    2004-01-01

    The abundance of alpha-process elements such as magnesium and carbon relative to iron measured from the broad emission lines of QSOs can serve as a diagnostic of the star formation and chemical enrichment histories of their host galaxies. We investigate the relationship between Fe/Mg and Fe/C abundance ratios and the resulting Fe II / Mg II 2800A and Fe II / 1900A-blend flux ratios, both of which have been measured in QSOs out to redshifts of approximately six. Using a galactic chemical evolution model based on a starburst in a giant elliptical galaxy, we find that these flux ratios are good tracers of the chemical enrichment of the nuclei. However, the values of these ratios measured in objects at redshifts of approximately six suggest that iron enrichment has occurred more rapidly in these objects than predicted by the assumed elliptical starburst model, under currently favored cosmologies.