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Sample records for 1-6ign fe-cu 7-12ign

  1. Measurement of thermoelectric power of Fe-Cu binary alloys

    In INSS, non-destructive evaluation (NDE) of irradiation embrittlement of low alloy steel using thermoelectric power (TEP) measurement has been considered, as well as NDE of thermal aging of cast duplex stainless steel which has been studied in recent years. Material degradation is evaluated based on a relation between progress of the degradation and change in TEP due to change in material structure caused by the degradation event. So it is necessary for NDE of irradiation embrittlement to measure the change in TEP due to precipitation of Cu contained as an impurity, which is known as one of the reasons for the embrittlement. In this study, TEP of Fe-Cu binary alloys with different Cu content was measured for investigation of the relationship between TEP of the alloys and Cu content. In addition, appropriateness of measuring TEP of Fe-Cu binary alloy in the same way to measure TEP of duplex stainless steel was examined. It was found that increment of Cu contained in the alloys changed TEP in a negative direction and the rate was evaluated as -6.6μV/K/wt%Cu. There were the cases that it took 20 minutes for measurement values to become stable in measurement of Fe-Cu binary alloys. It was much longer than the time taken in measurement of duplex stainless steel. So the measurement time per a point was extended to 60 minutes in case of Fe-Cu binary alloys. (author)

  2. Mechanical alloying in the Fe-Cu system

    Jiang, Jianzhong; Gente, C.; Bormann, R.

    The studies of mechanical alloying on the Fe-Cu system, as a model system for those with positive heats of mixing, are reviewed. Several problems involved in the mechanical alloying process are discussed. For example, (1) whether alloying occurs on an atomic level; (2) what the solid solubility in...... the Fe-Cu system is; (3) where the positive energy is stored in the alloys; (4) what the decomposition process of the supersaturated alloys is; and (5) what type of magnetic properties the new materials have. The elucidation of these problems will shed light on the understanding of the mechanisms for...... the preparation of materials under highly non-equilibrium conditions in systems with positive heats of mixing by mechanical alloying....

  3. Fabrication of oriented L10-FeCuPd and composite bcc-Fe/L10-FeCuPd nanoparticles: Alloy composition dependence of magnetic properties

    Oriented and well-isolated L10-FeCuPd ternary alloy nanoparticles have been fabricated by electron-beam evaporation followed by postdeposition annealing. A single L10 phase was formed in the FeCuPd nanoparticles with (Fe+Cu) content lower than 48 at. %. A strong preferential c-axis orientation along the film normal direction was achieved by Cu addition, which leads to a strong perpendicular magnetic anisotropy. Also, a lowering of the ordering temperature by 50 K compared to the binary L10-FePd nanoparticles was achieved by Cu addition. By contrast, composite particles composed of the bcc Fe and the L10-FeCuPd were formed when the (Fe+Cu) content was higher than 52 at. %. Coexistence of the bcc Fe and the L10-FeCuPd was confirmed by high-resolution transmission electron microscopy and nanobeam electron diffraction. It was found that perpendicular magnetic anisotropy of the L10-FeCuPd nanoparticles on the NaCl substrate is sensitive to the alloy composition

  4. Magnetoresistance of electrodeposited NiFeCu alloys

    Esmaili, S., E-mail: esmaili@shirazu.ac.ir [Department of Materials Science and Engineering, School of Engineering, Shiraz University, Shiraz (Iran, Islamic Republic of); Bahrololoom, M.E. [Department of Materials Science and Engineering, School of Engineering, Shiraz University, Shiraz (Iran, Islamic Republic of); Peter, L. [Research Institute for Solid State Physics and Optics, Hungarian Academy of Sciences, Budapest (Hungary)

    2012-01-01

    NiFeCu alloy films were electrodeposited from baths containing nickel sulfate and/or nickel sulfamate. All samples were pulse plated in the potentiostatic mode. The room temperature magnetoresistances of the films were measured showing anisotropic magnetoresistances up to 1.5%. The anisotropic magnetoresistances increased with the addition of sulfamic acid to the sulfate bath. Samples deposited from the bath with high sulfamate concentration showed a giant magnetoresistance behavior. To characterize the films, scanning electron microscopy and X-ray diffraction were used.

  5. Photoelectron diffraction of magnetic ultrathin films: Fe/Cu(001)

    Tobin, J.G. (Lawrence Livermore National Lab., CA (USA)); Wagner, M.K. (Wisconsin Univ., Madison, WI (USA). Dept. of Chemistry); Guo, X.Q.; Tong, S.Y. (Wisconsin Univ., Milwaukee, WI (USA). Dept. of Physics)

    1991-01-03

    The preliminary results of an ongoing investigation of Fe/Cu(001) are presented here. Energy dependent photoelectron diffraction, including the spin-dependent variant using the multiplet split Fe3s state, is being used to investigate the nanoscale structures formed by near-monolayer deposits of Fe onto Cu(001). Core-level photoemission from the Fe3p and Fe3s states has been generated using synchrotron radiation as the tunable excitation source. Tentatively, a comparison of the experimental Fe3p cross section measurements with multiple scattering calculations indicates that the Fe is in a fourfold hollow site with a spacing of 3.6{Angstrom} between it and the atom directly beneath it, in the third layer. This is consistent with an FCC structure. The possibility of utilizing spin-dependent photoelectron diffraction to investigate magnetic ultrathin films will be demonstrated, using our preliminary spectra of the multiplet-split Fe3s os near-monolayer Fe/Cu(001). 18 refs., 10 figs.

  6. Microstructural and magnetic characterizations of CoFeCu electrodeposited in self-assembled mesoporous silicon

    Self-assembled mesoporous silicon with quasi-regular pore arrangements has been fabricated by the electrochemical anodization process in hydrofluoric acid solution. CoFeCu was electrodeposited in this structure from a bath containing sodium acetate as a complexing agent with a pH value of 5. The effect of current density on the morphology, the structure and the magnetic properties of CoFeCu deposit was studied by SEM, EDS, DRX and VSM. It has been shown that the morphology and structure of samples were strongly influenced by the current density and etching duration. The micrographs show the vertical and branched nanowires and also a discontinuous growth of wires. Further, the growth of a thick layer from the grain boundaries of released CoFeCu wires is produced. The magnetic hysteresis loops demonstrate that the CoFeCu nanowires exhibit easy magnetic axis perpendicular to the PS channels axis when the current density varied from 3 to 10 mA/cm2. Nevertheless, they reveal a no magnetic anisotropy of CoFeCu nanostructures deposited only in the outside of porous silicon, probably due to the vanishing the shape anisotropy. - Highlights: • CoFeCu deposit has been electrodeposited on self assembled mesoporous silicon. • SEM observation shows that CoFeCu embedded in Porous silicon channels. • Magnetic measurements show the anisotropy magnetic behavior of CoFeCu nanostructures. • The growth rate of nanowires is enhanced with an increase of current density

  7. Time evolution of morphology in mechanically alloyed Fe-Cu

    Being widely accessible as well as already utilised in many applications, Fe-Cu acts as an ideal binary model alloy to elaborate the enforced nonequilibrium enhanced solubility in such a solution system that shows a limited regime of miscibility and characterised by a large positive heat of mixing. In addition to the detailed analysis of ball milled Fe-Cu powders by means of Atom Probe Tomography (APT), site specific structural analysis has been performed in this study using Transmission Electron Microscopy (TEM). In this contribution results on powders with low Cu concentrations (2.5-10 at%) are presented. Combining a ductile element (Cu, fcc) and a brittle one (Fe, bcc), striking differences in morphology were expected and found on all length-scales, depending on the mixing ratio of the two elements. However, not only could the atomic mixing of Fe and Cu be evaluated, but also the distribution of impurities, mostly stemming from the fabrication procedure. The combination of APT and TEM enables a correlation between the structural evolution and the chemical mixing during the milling process. For the first time, a clear distinction can be drawn between the morphological evolution at the surface and in the interior of the powder particles. This became possible owing to the site specific sample preparation of TEM lamellae by Focussed Ion Beam (FIB). Surprisingly, the texture arising from the ball milling process can directly be related to the classical rolling texture of cold rolled Fe. In addition, full homogeneity can be achieved even on the nano-scale for this material as shown by APT, resulting in an extended miscibility region in comparison to the equilibrium phase diagram. Grain sizes were determined by means of XRD and TEM. The strain corrected XRD results are in very good agreement with the values derived by TEM, both confirming a truly nanocrystalline structure. -- Research highlights: → Morphology and homogeneity of ball milled Fe-Cu were followed by XRD

  8. Time evolution of morphology in mechanically alloyed Fe-Cu

    Wille, Catharina Gabriele

    2011-05-01

    Being widely accessible as well as already utilised in many applications, Fe-Cu acts as an ideal binary model alloy to elaborate the enforced nonequilibrium enhanced solubility in such a solution system that shows a limited regime of miscibility and characterised by a large positive heat of mixing. In addition to the detailed analysis of ball milled Fe-Cu powders by means of Atom Probe Tomography (APT), site specific structural analysis has been performed in this study using Transmission Electron Microscopy (TEM).In this contribution results on powders with low Cu concentrations (2.5-10 at%) are presented. Combining a ductile element (Cu, fcc) and a brittle one (Fe, bcc), striking differences in morphology were expected and found on all length-scales, depending on the mixing ratio of the two elements. However, not only could the atomic mixing of Fe and Cu be evaluated, but also the distribution of impurities, mostly stemming from the fabrication procedure. The combination of APT and TEM enables a correlation between the structural evolution and the chemical mixing during the milling process. For the first time, a clear distinction can be drawn between the morphological evolution at the surface and in the interior of the powder particles. This became possible owing to the site specific sample preparation of TEM lamellae by Focussed Ion Beam (FIB). Surprisingly, the texture arising from the ball milling process can directly be related to the classical rolling texture of cold rolled Fe. In addition, full homogeneity can be achieved even on the nano-scale for this material as shown by APT, resulting in an extended miscibility region in comparison to the equilibrium phase diagram. Grain sizes were determined by means of XRD and TEM. The strain corrected XRD results are in very good agreement with the values derived by TEM, both confirming a truly nanocrystalline structure. © 2011 Elsevier B.V.

  9. Formation of an icosahedral phase in ion-irradiated Fe/Cu multilayers

    An icosahedral phase has been observed for the first time in the equilibrium immiscible Fe-Cu system. The new metastable phase was formed by directed xenon ion mixing of Fe/Cu multilayers at room temperature and without any amorphous-to-quasi-crystalline phase transition. The atomic concentration of this phase was determined by in situ energy-dispersive spectroscopy (EDS) to be around Fe60Cu40. (author)

  10. Dechlorination of carbon tetrachloride by the catalyzed Fe-Cu process

    XU Wen-ying; GAO Ting-yao

    2007-01-01

    The electrochemical reduction characteristics of carbon tetrachloride (CT) were investigated using cyclic voltammetry in this study. In addition, the difference in reduction mechanisms of CT between Master Builders' iron and the catalyzed Fe-Cu process was discussed. The results showed that CT was reduced directly on the surface of copper rather than by atomic hydrogen produced at the cathode in the catalyzed Fe-Cu process. The reduction was realized largely by atomic hydrogen in Master Builders' iron. The entire CT in 350 ml aqueous solution with 320 mg/L was reduced to trichloromethane and dichloromethane in 2.25 h when 100 g of scrap iron with Fe/Cu ratio of 10:1 (w/w) were used. Moreover, the reduction rate slowed with time. CT could be reduced at acidic, neutral and alkaline pH from solution by Fe-Cu bimetallic media, but the mechanisms were different. The degradation rate was not significantly influenced by pH in the catalyzed Fe-Cu process; in Master Builders' iron it clearly increased with decreasing pH. The kinetics of the reductions followed pseudo-first order in both cases. Furthermore, the reductions under acidic conditions proceeded faster than that under the neutral and alkaline conditions. The catalyzed Fe-Cu process was superior to Master Builders' iron in treating CT-containing water and this advantage was particularly noticeable under alkaline conditions. The reduction was investigated in the cathode (Cu) and anode (Fe) compartments respectively, the results showed that the direct reduction pathway played an important role in the reduction by the catalyzed Fe-Cu process. The catalyzed Fe-Cu process is of practical value.

  11. Microstructural and magnetic characterizations of CoFeCu electrodeposited in self-assembled mesoporous silicon

    Fortas, G., E-mail: g.fortas@gmail.com [Centre de Recherche en Technologie des Semi-conducteur pour l’Energétique, Bd. 2 Frantz Fanon, les sept merveilles B.P.140, Alger (Algeria); Université des Sciences et de la Technologie Houari Boumediene, Faculté des Physique, BP 32 El Alia 16111 Bab Ezzouar, Alger (Algeria); Haine, N. [Université des Sciences et de la Technologie Houari Boumediene, Faculté des Physique, BP 32 El Alia 16111 Bab Ezzouar, Alger (Algeria); Sam, S.; Gabouze, N. [Centre de Recherche en Technologie des Semi-conducteur pour l’Energétique, Bd. 2 Frantz Fanon, les sept merveilles B.P.140, Alger (Algeria); Saifi, A. [Université Mouloud Mammeri, laboratoire de physique et de chimie quantique, BP No. 17 RP Hasnaoua Tizi-Ouzou 15000 (Algeria); Ouir, S. [Université Said SDB, Route De Soumaa BP 270, Blida (Algeria); Menari, H. [Centre de Recherche en Technologie des Semi-conducteur pour l’Energétique, Bd. 2 Frantz Fanon, les sept merveilles B.P.140, Alger (Algeria)

    2015-03-15

    Self-assembled mesoporous silicon with quasi-regular pore arrangements has been fabricated by the electrochemical anodization process in hydrofluoric acid solution. CoFeCu was electrodeposited in this structure from a bath containing sodium acetate as a complexing agent with a pH value of 5. The effect of current density on the morphology, the structure and the magnetic properties of CoFeCu deposit was studied by SEM, EDS, DRX and VSM. It has been shown that the morphology and structure of samples were strongly influenced by the current density and etching duration. The micrographs show the vertical and branched nanowires and also a discontinuous growth of wires. Further, the growth of a thick layer from the grain boundaries of released CoFeCu wires is produced. The magnetic hysteresis loops demonstrate that the CoFeCu nanowires exhibit easy magnetic axis perpendicular to the PS channels axis when the current density varied from 3 to 10 mA/cm{sup 2}. Nevertheless, they reveal a no magnetic anisotropy of CoFeCu nanostructures deposited only in the outside of porous silicon, probably due to the vanishing the shape anisotropy. - Highlights: • CoFeCu deposit has been electrodeposited on self assembled mesoporous silicon. • SEM observation shows that CoFeCu embedded in Porous silicon channels. • Magnetic measurements show the anisotropy magnetic behavior of CoFeCu nanostructures. • The growth rate of nanowires is enhanced with an increase of current density.

  12. Quantum-well states and induced magnetism in Fe/CuN/Fe bcc (001) trilayers

    Niklasson, A.M.N.; Mirbt, S.; Skriver, Hans Lomholt;

    1996-01-01

    profiles of two single Fe/Cu interfaces. The small deviations from this simple superposition are shown to be a consequence of quantum-well states confined within the paramagnetic spacer. This connection is confirmed by direct calculation of the state density. The results are of conceptual interest for the......We have used a first-principles Green's function technique to investigate the formation of magnetic moments in Fe/Cu-N/Fe bcc (001) trilayers. We show that the magnetic moment in the paramagnetic spacer material to a first approximation may be described as a linear superposition of the magnetic...

  13. Effect of foliar applied (Zn, Fe, Cu and Mn) in citrus production

    A study was conducted to evaluate the impact of micronutrients (Zn, Fe, Cu and Mn) on sweet orange (Citrus Sinensis L.), blood red var., on farmer's orchard at Khanpur, district Haripur, NWFP, during 2002-03. Micronutrients were applied in foliar sprays over the canopy of each tree. The main effects and interactions of Zinc sulphate (Zn), iron sulphate (Fe), Copper Sulphate (Cu) and Manganese Sulphate (Mn) were studied in factorial combinations. A basal dose of nitrogen, phosphorus and potassium was applied at the rate 1.5, 1 and 1 kg tree/sup -1/. Zn, Fe, Cu and Mn were applied alone and in various combinations at the rate 0.115, 0.057, 0.05 and 0.13 kg in 100 liters of water. Application of micronutrients significantly increased Zn, Fe, Cu and Mn concentrations in leaves, compared with control. Zn treatments significantly increased the yield, number of fruit and total sugar. Manganese treatments significantly increased the total soluble solids and reduced the acidity of fruit juice. Other quality parameters, including fruit size, percent peel, percent pulp, sugar as well as total soluble solids, were improved with the application of Zn, Fe, Cu and Mn. (author)

  14. Effect of Applied Current Density on Morphological and Structural Properties of Electrodeposited Fe-Cu Films

    Umut Sarac; M. Celalettin Baykul

    2012-01-01

    A detailed study has been carried out to investigate the effect of applied current density on the composition, crystallographic structure, grain size, and surface morphology of Fe-Cu films. X-ray diffraction (XRD) results show that the films consist of a mixture of face-centered cubic (fcc) Cu and body centered cubic (bcc) ~-Fe phases. The average crystalline size of both Fe and Cu particles decreases as the applied current density becomes more negative. Compositional analysis of Fe-Cu films indicates that the Fe content within the films increases with decreasing current density towards more negative values. Scanning electron microscopy (SEM) and atomic force microscopy (AFM) have been used to investigate the surface morphology of Fe-Cu films. It is observed that the surface morphology of the films changes from dendritic structure to a cauliflower structure as the applied current density becomes more negative. The surface roughness and grain size of the Fe-Cu films decrease with decreasing applied current density towards more negative values.

  15. Fine-particle magnetism in nanocrystalline Fe-Cu-Nb-Si-B at elevated temperatures

    Magnetic interactions between the nanocrystalline particles in FeCuNbSiB are studied above the Curie temperature of the intergranular amorphous phase. It is shown that with increasing volume fraction of nanocrystalline particles, the interparticle interaction increasingly suppresses superparamagnetic fluctuations and the transition to superferromagnetic behavior is observed. ((orig.))

  16. Compressibility of nanostructured Fe-Cu materials prepared by mechanical milling

    Jiang, Jianzhong; Olsen, J.S.; Gerward, Leif;

    1999-01-01

    The compressibility of nanostructured Fe-Cu materials prepared by mechanical milling has been investigated by in-situ high-pressure x-ray diffraction using synchrotron radiation. It is found that the bulk modulus of both fcc-Cu and bcc-Fe phases decreases with decreasing grain sizes. The unstable...

  17. Microstructure and mechanical properties of Fe-Cu-Sn sintered alloy%Fe-Cu-Sn烧结体的显微组织与力学性能

    何娟; 王日初; 彭超群; 郑虎春

    2011-01-01

    分别采用水雾化Fe-30%Cu合金粉末和单质Sn、Fe、Cu元素粉末为原料制备Fe-Cu-Sn合金,研究原料粉末和Sn含量(质量分数)对Fe-Cu-Sn烧结体致密度、冲击韧性、硬度和抗弯强度的影响.结果表明:与采用元素混合粉末相比,采用合金化程度较高的Fe-30%Cu(质量分数,下同)合金粉末为原料能大幅提高850℃烧结的Fe-Cu-5%Sn合金的致密度和力学性能,其致密度由82.8%提高到94.3%,硬度、冲击韧性和抗弯强度分别提高52%、84%和109%:当Sn的质量分数w(Sn)为3%-15%时,随着Sn质量分数增加,合金的硬度增大,冲击韧性和抗弯强度先增加后减小,其中w(Sn)为5%时,其抗弯强度和冲击韧性都较高,分别为977 MPa和11.6 J/cm2.当烧结体为"双重结构"组织时,其力学性能显著提高.

  18. The energetic and structural properties of bcc NiCu, FeCu alloys: a first-principles study

    Xie, Yao-Ping; Zhao, Shi-Jin

    2011-01-01

    Using special quasirandom structures (SQS's), we perform first-principles calculations studying the metastable bcc NiCu and FeCu alloys which occur in Fe-Cu-Ni alloy steels as precipitated second phase. The mixing enthalpies, density of state, and equilibrium lattice parameters of these alloys are reported. The results show that quasi-chemical approach and vegard rule can well predict the energetic and structural properties of FeCu alloys but fail to yield that of NiCu. The reason rests with ...

  19. 快淬态纳米晶Fe-Cu-Ta-Si-B软磁金属薄带的制备%Preparation of As-quenched Nanocrystalline Fe-Cu-Ta-Si-B Soft Magnetic Ribbons

    胡季帆; 李波; 秦宏伟

    2009-01-01

    Fe-Cu-Ta-Si-B纳米晶金属薄带可以通过快淬技术直接制备,而无需退火过程.对比Fe-Cu-Ta-Si-B快淬纳米晶薄带,发现相同Cu含量下,a-Fe(Si)更易在Fe-Cu-Nb-Si-B快淬态薄带中析出.在快淬态Fe-Cu-Ta-Si-B金属薄带中,适当高的Cu含量有利于α-Fe(Si)的成核;但过高的Cu含量反而弱化了纳米晶化,这是由于团簇效应粗化了Cu颗粒的尺寸,却减少了a-Fe(Si)的有效成核位置.

  20. Surface segregation and surface tension in liquid Fe-Cu alloys

    A simple statistical mechanics model has been used to study the temperature dependence of the surface properties of Fe-Cu liquid alloys. The calculated values for the composition dependence of surface segregation indicates that Cu atoms segregate to the surface and, in addition, that the surface tension in Fe-Cu alloys decreases with increasing copper content. Furthermore, our formalism is able to predict the temperature dependence of the surface properties for the liquid alloy based only on knowledge of the results at the melting point. This illustrates that the model used provides a simple recipe to extract information in the undercooled region about the dependence of surface properties in liquid binary alloys. In addition, close to the decomposition temperature, the surface concentration of Cu increases sharply in the undercooled region. (orig.)

  1. Precipitation behavior of B2-like particles in Fe-Cu binary alloy

    2002-01-01

    The precipitation behavior in Fe-Cu binary alloy was investigated under transmission electron microscope (TEM) during aging at 650℃ for the time range of to 300 h. In addition to the zones with higher copper content and -Cu were observed, a metastable phase with B2-like structure was found in the early stage of the precipitation process, which is quite different from the equilibrium copper phase shown inthe Fe-Cu binary phase diagram and has perfect coherent relationship to the -Fe matrix. The appearance of B2-like structure is very important concerning the mechanism of aging strengthening effect and mechanical properties of corresponding engineering steels and alloys containing copper.

  2. Heat content of liquid Fe-Cu-Si alloys formed in the melting treatment process of domestic waste incineration residue

    Washizu, T. [Nippon Steel Corp., Ohita (Japan). Ohita Works; Nagasaka, T.; Hino, M. [Tohoku Univ., Sendai (Japan). Dept. of Metallurgy

    2002-04-01

    Some new melting processes for the ash have been developed to solve the problems on increasing volume of ash generated from municipal waste incinerators. The metal phase formed in this melting process generally consists of Fe-Cu-Si-P-C containing a small amount of other heavy metals, but their phase equilibria and physico-chemical properties are unknown. The present work aimed at determining the thermochemical properties of liquid Fe-Cu-Si alloys, which establish the basic system in this melting process. The heat contents of liquid Fe, Fe-Cu and Fe-Cu-Si alloys have been directly measured with a drop calorimeter at mainly 2073 K in the present work. The observed heat content and the enthalpy of mixing of the alloys were assessed by a thermodynamic model. The input energy which should be supplied to melt the metal phase in the new melting treatment process was also discussed. (orig.)

  3. Heat content of liquid Fe-Cu-Si alloys formed in the melting treatment process of domestic waste incineration residue

    Some new melting processes for the ash have been developed to solve the problems on increasing volume of ash generated from municipal waste incinerators. The metal phase formed in this melting process generally consists of Fe-Cu-Si-P-C containing a small amount of other heavy metals, but their phase equilibria and physico-chemical properties are unknown. The present work aimed at determining the thermochemical properties of liquid Fe-Cu-Si alloys, which establish the basic system in this melting process. The heat contents of liquid Fe, Fe-Cu and Fe-Cu-Si alloys have been directly measured with a drop calorimeter at mainly 2073 K in the present work. The observed heat content and the enthalpy of mixing of the alloys were assessed by a thermodynamic model. The input energy which should be supplied to melt the metal phase in the new melting treatment process was also discussed. (orig.)

  4. Comparison of laser induced plasma and arc discharge emission spectra of Al, Fe, Cu and C

    Emission spectra of laser induced plasma and arc discharge were measured and compared for Al, Fe, Cu and C. Such a comparison shows a higher presence of ionized transitions, but also a higher background in the emission spectra of laser induced plasma than in arc discharge. It can be concluded that in general it is not possible to predict laser induced plasma for material analysis purposes, calibration by reference laser induced plasma spectra of pure elements in vacuum will be necessary. (Authors)

  5. Relaxation process of Fe(CuNb)SiB amorphous alloys investigated by dynamical calorimetry

    Zhu, J.; Clavaguera-Mora, M. T.; Clavaguera, N.

    1997-01-01

    Differential scanning calorimetry and dynamic differential scanning calorimetry were used to analyze the relaxation process of Fe(CuNb)SiB amorphous alloys. The Curie temperature(TC) evolution of the amorphous phase during relaxation as a function of heating rate, time and pre-annealing temperature were measured. Two distinct relaxation processes are observed, consequent with topological and chemical short range order changes.

  6. Hot extrusion for Al-Si-(Fe, Cu) hyper-eutectic cast alloys

    Yokoyama, Hisanaga; Umezawa, Osamu; Nagai, Kotobu; Kokubo, Kunio

    1999-01-01

    For hyper-eutectic Al-Si-(Fe, Cu) cast materials in large scale ingots, we have studied microstructural modification by thermomechanical treatment to produce a heavily deformable material. Cast materials contained coarse primary Si crystals in a few hundred micron diameter or acicular intermetallic compound in several hundred micron length. Even by multiple-step cold-rolling, sample fracture of the cast alloys occurred with more extrusion step to the cast materials. A novel process, repeated ...

  7. Relaxation process of Fe(CuNb)SiB amorphous alloys investigated by dynamical calorimetry

    Differential scanning calorimetry and dynamic differential scanning calorimetry were used to analyze the relaxation process of Fe(CuNb)SiB amorphous alloys. The Curie temperature (TC) evolution of the amorphous phase during relaxation as a function of heating rate, time and pre-annealing temperature were measured. Two distinct relaxation processes are observed, consequent with topological and chemical short range order changes. copyright 1997 American Institute of Physics

  8. Microwave absorbing properties and enhanced infrared reflectance of Fe/Cu composites prepared by chemical plating

    Fe/Cu composite samples with Cu particles depositing on carbonyl iron sheets were prepared by chemical plating. Cu additions were uniformly distributed on the grain boundaries of the flaky carbonyl iron while keeping the internal structure of iron. Meanwhile, we found that the chemical plating time made a key point on both the microwave absorbing properties and infrared emissivity. With the growth of chemical plating time, the value of reflection loss gives a linear decrease and the infrared emissivity is reduced with a tendency of index reduction. When the plating time is less than 30 min, the reflection loss of the samples maintains above −20 GHz, moreover, prolonging the plating time more than 30 min, the infrared emissivity of the samples is reduced to 0.50 or less. It can be concluded that both the microwave absorbing and infrared properties are excellent at the optimal plating time of 30 min. - Highlights: • The Fe/Cu composites have been prepared by flake carbonyl iron as substrate. • The Fe/Cu composites exhibit enhanced Infrared characteristics. • The samples hold the most of the absorbing capacity and possess low infrared emissivity by controlling plating time

  9. The effect of magnetic layer thickness on magnetic properties of Fe/Cu multilayer nanowires

    Fe/Cu multilayer nanowires were ac-pulse electrodeposited into the anodic aluminum oxide templates prepared by a two-step mild anodization technique. Transmission electron microscopy images showed the distinct layers with a relatively high contrast. A highly pure layer (∼99%) was achieved by tuning the proper ions ratio and optimizing the off-time between pulses of each layer in the single electrodeposition bath. Fe/Cu multilayer nanowires with 38 nm diameter were obtained. The effect of reducing the Fe layer thickness on the magnetic properties of Fe/Cu multilayer nanowires was investigated. It was seen that reducing the Fe layer thickness, thereby variation of rode- to disc-like multilayer nanowires, caused to rotate the magnetic easy axis from parallel to perpendicular to the wires axis. - Highlights: • Changing off-time and ac voltage enables control in segments of multilayer nanowire. • As TEM images show thickness of alternative layers was adjustable by pulse numbers. • A new technique was introduced to grow compositionally-modulated multilayer nanowire. • Two distinct Fe and Cu diffraction peaks indicates formation of two distinct phases. • Identical coercivity in IP and OOP configurations ascribed vanishing shape anisotropy

  10. The effect of magnetic layer thickness on magnetic properties of Fe/Cu multilayer nanowires

    Almasi-Kashi, M., E-mail: almac@kashanu.ac.ir [Department of Physics, University of Kashan, Kashan (Iran, Islamic Republic of); Institute of Nanoscience and Nanotechnology, University of Kashan, Kashan (Iran, Islamic Republic of); Ramazani, A. [Department of Physics, University of Kashan, Kashan (Iran, Islamic Republic of); Institute of Nanoscience and Nanotechnology, University of Kashan, Kashan (Iran, Islamic Republic of); Kheyri, F.; Jafari-Khamse, E. [Department of Physics, University of Kashan, Kashan (Iran, Islamic Republic of)

    2014-04-01

    Fe/Cu multilayer nanowires were ac-pulse electrodeposited into the anodic aluminum oxide templates prepared by a two-step mild anodization technique. Transmission electron microscopy images showed the distinct layers with a relatively high contrast. A highly pure layer (∼99%) was achieved by tuning the proper ions ratio and optimizing the off-time between pulses of each layer in the single electrodeposition bath. Fe/Cu multilayer nanowires with 38 nm diameter were obtained. The effect of reducing the Fe layer thickness on the magnetic properties of Fe/Cu multilayer nanowires was investigated. It was seen that reducing the Fe layer thickness, thereby variation of rode- to disc-like multilayer nanowires, caused to rotate the magnetic easy axis from parallel to perpendicular to the wires axis. - Highlights: • Changing off-time and ac voltage enables control in segments of multilayer nanowire. • As TEM images show thickness of alternative layers was adjustable by pulse numbers. • A new technique was introduced to grow compositionally-modulated multilayer nanowire. • Two distinct Fe and Cu diffraction peaks indicates formation of two distinct phases. • Identical coercivity in IP and OOP configurations ascribed vanishing shape anisotropy.

  11. Note: Resonance magnetoelectric interactions in laminate of FeCuNbSiB and multilayer piezoelectric stack for magnetic sensor

    Li, Jianqiang; Lu, Caijiang; Xu, Changbao; Zhong, Ming

    2015-09-01

    This paper develops a simple miniature magnetoelectric (ME) laminate FeCuNbSiB/PZT-stack made up of magnetostrictive Fe73.5Cu1Nb3Si13.5B9 (FeCuNbSiB) foils and piezoelectric Pb(Zr, Ti)O3 (PZT) multilayer stack vibrator. Resonant ME interactions of FeCuNbSiB/PZT-stack with different layers of FeCuNbSiB foil (L) are investigated in detail. The experimental results show that the ME voltage coefficient reaches maximum value of 141.5 (V/cm Oe) for FeCuNbSiB/PZT-stack with L = 6. The AC-magnetic sensitivities can reach 524.29 mV/Oe and 1.8 mV/Oe under resonance 91.6 kHz and off-resonance 1 kHz, respectively. The FeCuNbSiB/PZT-stack can distinguish small dc-magnetic field of ˜9 nT. The results indicate that the proposed ME composites are very promising for the cheap room-temperature magnetic field sensing technology.

  12. [Degradation of phenol with a Fe/cu-catalytic heterogeneous-Fenton process].

    Yang, Yue-Zhu; Li, Yu-Ping; Yang, Dao-Wu; Duan, Feng; Cao, Hong-Bin

    2013-07-01

    The catalysts of Fe/AC, Cu/AC and Fe-Cu/AC with active carbon as support were prepared by a wet impregnation method, and were characterized using X-ray diffraction (XRD), nitrogen adsorption and X-ray photoelectron spectroscopy (XPS) measurements; the catalytic heterogeneous-Fenton processes of phenol degradation with these catalysts were also investigated, and the degradation mechanism was discussed with analysis of intermediate products and electron spin resonance (ESR) measurement. The results showed that the active component states varied in different catalysts; CuO was the main state of Cu in Cu/AC and Fe exhibited various valence states in Fe/AC. The degradation rate of phenol with Fe/AC, Cu/AC and Fe-Cu/AC as catalyst in the initial 60 min reached 96.7%, 77.5% and 99%, respectively; the dissolution of a little active-component metal was found in Cu/AC and Fe-Cu/AC, but little Fe in Fe/AC was dissolved; the degradation of phenol was performed by heterogeneous Fe/AC instead of dissolved Fe, and the degradation rate was above 93% after Fe/AC was used for three cycle runs, showing a stable catalytic activity. Under the optimum conditions of pH = 3, T = 303 K, and 4.38 mmol x L(-1) H2O2, the removal of phenol and TOC in the Fe/AC-catalytic Fenton process could reach 97% and 53%, respectively, while little phenol was degraded without catalyst. The ESR results indicated that hydroxyl radical was produced in the catalytic decomposition of H2O2 with Fe/AC as catalyst, demonstrating that the degradation of phenol mainly followed an oxidation pathway of hydroxyl radical; intermediates such as hydroquinone, p-benzenequinone and catechol were obtained, and the results showed thatortho- and para-substitution reaction by hydroxyl might be the main mechanism of phenol oxidation. PMID:24027996

  13. Positron annihilation study of neutron irradiated pure Fe and Fe-Cu binary alloys

    The hardening and embrittlement of Reactor Pressure Vessel (RPV) steels is of great concern in the actual nuclear power plant life assessment. This embrittlement is caused by irradiation-induced damage, like vacancies, interstitials, solutes and their clusters. Fe-Cu binary alloys are often used to mimic the behaviour of such steels. Their study allows identifying some of the defects responsible of the hardening, especially when compared to pure iron or C-micro-alloyed iron. Owing to their self-seeking and selective trapping, positrons are used to determine the nature of these defects. Recently, at SCK.CEN, a new Positron Annihilation Spectroscopy (PAS) setup has been built, calibrated and optimized to measure the Coincidence Doppler Broadening (CDB) and Lifetime (LT) of neutron irradiated materials. This set-up has been used to measure the CDB and LT of n-irradiated pure Fe and Fe-Cu alloys. It is found that the clustering of Cu take place at the very early stages of irradiation using the CDB while LT measurement are showing much more vacancy clustering for low Cu alloys than in the higher ones. Increasing the neutron dose up to 1.3 x 1020 n/m2, allows the follow up of the kinetic of Cu and V-clustering especially in Fe-Cu alloys. It is found that both copper and carbon decrease the size of vacancy-cluster, when added to iron. (copyright 2007 WILEY-VCH Verlag GmbH and Co. KGaA, Weinheim) (orig.)

  14. Template-grown NiFe/Cu/NiFe nanowires for spin transfer devices

    Piraux, L.; Renard, K.; Guillemet, R.;

    2007-01-01

    method allows the electrical connection of one single nanowire in a large assembly of wires embedded in anodic porous alumina supported on Si substrate with diameters and periodicities to be controllable to a large extent. Both magnetic excitations and switching phenomena driven by a spin......-polarized current were clearly demonstrated in our electrodeposited NiFe/Cu/ NiFe trilayer nanowires. This novel approach promises to be of strong interest for subsequent fabrication of phase-locked arrays of spin transfer nano-oscillators with increased output power for microwave applications. © 2007 American...

  15. Probing structure-property relationships in perpendicularly magnetized Fe/Cu(001) using MXLD and XPD

    Cummins, T.R.; Waddill, G.D. [Univ. of Missouri, Rolla, MO (United States); Goodman, K.W. [Lawrence Berkeley National Lab., CA (United States)] [and others

    1997-04-01

    Magnetic X-ray Linear Dichroism (MXLD) in Photoelectron Spectroscopy and X-Ray Photoelectron Diffraction (XPD) of the Fe 3p core level have been used to probe the magnetic structure-property relationships of perpendicularly magnetized Fe/Cu(001), in an element-specific fashion. A strong MEXLD effect was observed in the high resolution photoelectron spectroscopy of the Fe 3p at {open_quotes}normal{close_quotes} emission and was used to follow the loss of perpendicular ferromagnetic ordering as the temperature was raised toward room temperature. In parallel with this, {open_quotes}Forward Focussing{close_quotes} in XPD was used as a direct measure of geometric structure in the overlayer. These results and the implications of their correlation will be discussed. Additionally, an investigation of the effect of Mn doping of the Fe/Cu(001) will be described. These measurements were performed at the Spectromicroscopy Facility (Beamline 7.0.1) of the Advanced Light Source.

  16. Atom probe study of Cu-segregation in thermal aging of binary Fe-Cu alloys

    Fe-Cu binary alloy is commonly used as a prototype model alloy for Pressurized Water Reactor (PWR) pressure vessel steels, especially for the study of radiation damage. This is because of the fact that Cu is one of the main solutes, segregation of which is known to cause major embrittlement in reactor pressure vessel (RPV) steels under nuclear radiation. Interestingly, similar solute segregation is often noticed in case of radiation-free long-term thermal aging experiments as well. Therefore, thermal aging experiment which is considerably simpler can be effectively utilized to study the solute segregation behaviour and emulate radiation-induced damage. With this objective, a series of binary Fe-Cu alloys with Cu concentration varying from 0.1 at. % - 1.4 at. % were prepared by vacuum arc melting. They were subsequently cold-rolled, followed by homogenization at 800 C and water quenching. The homogenized samples were then aged at 500 C for the following different durations: 1, 3, 5, 8, 25, 50 and 100 h. 3DAP is an indispensable tool to study solute segregation at this length scale, and the current study will present the results of a detailed 3DAP investigation of the evolution of the thermal damage in these binary prototype alloys. (author)

  17. Degradation of high energetic and insensitive munitions compounds by Fe/Cu bimetal reduction

    Highlights: ► Bimetal iron–copper particles are highly effective for treating waste streams containing energetic components such as RDX, TNT, HMX, NTO, and DNAN. ► First report ever on the degradation of NTO and DNAN from real industrial wastewater using bimetallic particles. ► Assessment of pH effect on NTO degradation by bimetal. ► Nitroaromatic structure of TNT exhibits a high preference for the metal surface and faster degradation. - Abstract: A reductive technology based on a completely mixed two-phase reactor (bimetallic particles and aqueous stream) was developed for the treatment of aqueous effluents contaminated with nitramines and nitro-substituted energetic materials. Experimental degradation studies were performed using solutions of three high energetics (RDX, HMX, TNT) and three insensitive-munitions components (NTO, NQ, DNAN). The study shows that, on laboratory scale, these energetic compounds are easily degraded in solution by suspensions of bimetallic particles (Fe/Ni and Fe/Cu) prepared by electro-less deposition. The type of bimetal pair (Fe/Cu or Fe/Ni) does not appear to affect the degradation kinetics of RDX, HMX, and TNT. The degradation of all components followed apparent first-order kinetics. The half-lives of all compounds except NTO were under 10 min. Additional parameters affecting the degradation processes were solids loading and initial pH.

  18. Correlation between zirconium oxide impedance and corrosion behavior of Zr-Nb-Sn-Fe-Cu alloys

    To evaluate the correlation of Zr oxide impedance and corrosion behavior of Zr-Nb-Sn-Fe-Cu alloys, the corrosion behavior of the alloys was tested in the autoclave containing 70 ppm LiOH solution at 360 .deg. C. The characteristics of the oxide on the alloys were investigated by using the electrochemical impedance spectrosocpy (EIS) method. The corrosion resistance of the alloys was evaluated from the corrosion rate determined as a function of the concentration of Nb. The equivalent circuit of the oxide was composed on the base of the spectrum from EIS measurements on the oxide layers that had formed at pre-and post-transition regions on the curve of corrosion rate. By using the capacitance characteristics of the equivalent circuit, the thickness of impervious layer, it's electrical resistance and characteristics of space charge layer were evaluated. The corrosion characteristics of the Zr-Nb-Sn-Fe-Cu alloys were successfully explained by applying the EIS test results

  19. Impact of biogenic nanoscale metals Fe, Cu, Zn and Se on reproductive LV chickens

    Khiem Nguyen, Quy; Dieu Nguyen, Duy; Kien Nguyen, Van; Thinh Nguyen, Khac; Chau Nguyen, Hoai; Tin Tran, Xuan; Nguyen, Huu Cuong; Tien Phung, Duc

    2015-09-01

    Using biogenic nanoscale metals (Fe, Cu, ZnO, Se) to supplement into diet premix of reproductive LV (a Vietnamese Luong Phuong chicken breed) chickens resulted in certain improvement of poultry farming. The experimental data obtained showed that the farming indices depend mainly on the quantity of nanocrystalline metals which replaced the inorganic mineral component in the feed premix. All four experimental groups with different quantities of the replacement nano component grew and developed normally with livability reaching 91 to 94%, hen’s bodyweight at 38 weeks of age and egg weight ranged from 2.53-2.60 kg/hen and 50.86-51.55 g/egg, respectively. All these farming indices together with laying rate, egg productivity and chick hatchability peaked at group 5 with 25% of nanoscale metals compared to the standard inorganic mineral supplement, while feed consumption was lowest. The results also confirmed that nanocrystalline metals Fe, Cu, ZnO and Se supplemented to chicken feed were able to decrease inorganic minerals in the diet premixes at least four times, allowing animals to more effectively absorb feed minerals, consequently decreasing environmental pollution risks.

  20. REE and Trace Element Geochemistry of Yinachang Fe-Cu-REE Deposit, Yunnan Province, China

    杨耀民; 涂光炽; 胡瑞忠

    2004-01-01

    REE and other trace elements in ores, wall rocks, alkaline volcanic rocks and diabase dikes have been determined in the Yinachang Fe-Cu-REE deposit. Comparative studies of REE and trace element geochemical characteristics of these geological bodies indicate that the ores and alkaline volcanic rocks contain abundant REE and Y (65.9-4633)×10-6, with higher abundances of As, Mo, Nb, Co and U than those of the crust. Their chondrite-normalized patterns show a strong enrichment of LREE and a positive Eu anomaly, in contrast to those of the dolomites which are characterized by slight LREE enrichment and moderate negative Eu anomaly. The REE patterns of ores are similar to those of hydrothermal sediment cores in the East Pacific Rise, whereas the REE patterns of dolomites are similar to those of PAAS (Post-Archean Average Shale). In combination with the geological setting of the deposit, the primary ore-forming fluids might have higher REE and volatile elements, and might have been derived from mantle degassing, or the alkaline volcanic magmas. The Yinachang Fe-Cu-REE ore deposit is considered to be of volcanic exhalation-hydrothermal sedimentary origin.

  1. Artificial intelligence applied to atomistic kinetic Monte Carlo simulations in Fe-Cu alloys

    Vacancy migration energies as functions of the local atomic configuration (LAC) in Fe-Cu alloys have been systematically tabulated using an appropriate interatomic potential for the alloy of interest. Subsets of these tabulations have been used to train an artificial neural network (ANN) to predict all vacancy migration energies depending on the LAC. The error in the prediction of the ANN has been evaluated by a fuzzy logic system (FLS), allowing a feedback to be introduced for further training, to improve the ANN prediction. This artificial intelligence (AI) system is used to develop a novel approach to atomistic kinetic Monte Carlo (AKMC) simulations, aimed at providing a better description of the kinetic path followed by the system through diffusion of solute atoms in the alloy via vacancy mechanism. Fe-Cu has been chosen because of the importance of Cu precipitation in Fe in connection with the embrittlement of reactor pressure vessels of existing nuclear power plants. In this paper the method is described in some detail and the first results of its application are presented and briefly discussed

  2. The effect of grain size and phase constitution on the magnetic properties of Fe-Cu-Nb-Si-B

    Amorphous Fe-Cu-Nb-Si-B ribbons were annealed between 525 and 700 C. Crystallization processes were studied using X-ray diffraction and Moessbauer spectroscopy so as to follow the effect of crystallite size, alloy composition and phase constitution on the magnetic properties. ((orig.))

  3. Synthesis and magnetic properties of multilayer Ni/Cu and NiFe/Cu nanowires

    R S Liu; S C Chang; I Baginskiy; S F Hu; C Y Huang

    2006-07-01

    Highly ordered composite nanowires with multilayer Ni/Cu and NiFe/Cu have been fabricated by pulsed electrodeposition into nanoporous alumina membrane. The diameter of wires can be easily varied by pore size of alumina, ranging from 30 to 100 nm. The applied potential and the duration of each potential square pulse determine the thickness of the metal layers. The nanowires have been characterized by transmission electron microscopy (TEM), magnetic force microscopy (MFM), and vibrating sample magnetometer (VSM) measurements. The MFM images indicate that every ferromagnetic layer separated by Cu layer was present as single isolated domain-like magnet. This technique has potential use in the measurement and application of magnetic nanodevices.

  4. Annealing effects on the microwave linewidth broadening of FeCuNbSiB ferromagnetic films

    We systematically investigate the annealing effects on the microwave linewidth broadening of FeCuNbSiB ferromagnetic films with thickness of 100 nm. We correlate the non-uniform residual stress obtained from grazing incidence x-ray diffraction measurements with the ferromagnetic resonance (FMR) linewidth due to effective field inhomogeneities measured from broadband ferromagnetic resonance absorption measurements. We also estimate the annealing temperature effect on the Gilbert and two-magnon scattering contributions to the total ferromagnetic resonance FMR linewidth. We show that the effective field inhomogeneities constitute the main contribution to the microwave linewidth, while this contribution is related to the non-uniform residual stress in the films which is reduced by thermal annealing

  5. Nanometer Stripe Microstructure of Supersaturated Solid Solution in Fe-Cu Alloy

    REN Hui-ping; WANG Hai-yan; LIU Zong-chang; AN Zhi-guo

    2007-01-01

    Strengthening due to precipitation of Cu in the α-Fe matrix is an important phenomenon utilized in the design of HSLA steels. In the present work, the microstructure of supersaturated solid solution in Fe-1.18%Cu binary alloy was investigated by means of high resolution electron microscopy. The results indicated that the solid solution was heterogeneous, there were lots of Cu atom clusters, which consisted of diffractive stripe microstructure similar to twin crystal. Orientation deviation was observed between two (110)α planes in diffractive stripes, which results in light and shade contrast. Furthermore, formation mechanisms of the nanometre stripe microstructure were discussed in terms of the interaction of Cu and Fe atoms in the Fe-Cu binary alloys.

  6. The lattice structure of nanocrystalline Fe-Cu-Si-B alloys

    Liu, X. D.; Lu, K.; Ding, B. Z.; Hu, Z. Q.; Zhu, J.; Jiang, J.

    1994-02-01

    Nanocrystalline Fe-Cu-Si-B alloys with different grain sizes were synthesized by crystallization of an amorphous alloy. Two nanophases, α-Fe(Se) and Fe 2B, were noticed in all samples. XRD results reveal that the lattice constant of the α-Fe(Si) phase increases; the a-axis is elongated and the c-axis is shortened in the Fe 2B phase upon reducing the grain size. Based on the thermodynamic analysis, the changes in the lattice parameters were attributed to the solution of vacancies in the above two phases. Owing to the lattice distortion of the α-Fe(Si) and Fe 2B phases, the crystallite with small size is found to exhibit a disordered character to some extent, which is manifested by large values of the half linewidth (HLW) and isomer shift (IS) of various Fe configurations in the Mössbauer parameters.

  7. Preparation and characterization of electrodeposited Fe and Fe/Cu nanowires

    Dubois, S.; Chassaing, E.; Duvail, J. L.; Piraux, L.; Waals, M. G.

    1999-09-01

    Fe and Fe/Cu multilayered nanowires with layer thicknesses in the 10nm range were successfully synthesized within the voids of nanoporous polycarbonate membranes and characterized by transmission electron microscopy. Magnetization measurements show that the shape anisotropy of individual Fe wires dominates the magnetic properties. Fe(8 nm)/Cu(10 nm) multilayered nanowires show CPP-GMR ratios as large as 12% at low temperature. The variations of the CPP-GMR as a function of the Cu layer thickness are consistent with the Valet-Fert model. Our data yield a value of about 0.3 for the bulk spin asymmetry coefficient β. Des nanofilaments constitués de Fe ou de multicouches Fe/Cu sont élaborés par dépôt électrochimique à l'intérieur des pores de membranes polycarbonate et caractérisés en microscopie électronique à transmission. Les propriétés magnétiques des nanofils de Fe sont très largement dominées par l'anisotropie de forme des fils. La magnéto-résistance géante (MRG) de multicouches Fe(8 nm)/Cu(10 nm) atteint 12 % à basse température tandis que la variation de la MRG est en bon accord avec le modèle de Valet-Fert. La valeur du coefficient d'asymétrie de spin β associé aux collisions au sein des couches de Fe est de l'ordre de 0.3.

  8. Study of Fe-Cu/ZSM-5 and its amination catalytic property%Fe-Cu/ZSM-5催化剂及其胺化催化性能研究

    赵锋伟; 淡保松; 王伟; 杨建明; 吕剑

    2009-01-01

    制备了一种Fe-Cu/ZSM-5胺化催化剂,考察其在乙醇胺选择性合成哌嗪、三乙烯二胺反应中的催化活性.结果表明,随着Fe、Cu负载量的增加,催化剂表面酸性逐渐向强酸方向位移,总酸量增加,反应转化率提高;Cu负载量对反应转化率及乙二胺选择性的影响相对较弱,但对哌嗪的生成有明显的促进作用;催化反应性能不仅受催化剂酸性的影响,还与负载组分的性质及负载组分与载体间的相互作用有关.%The synthesis of piperazine(PIP) and triethylene diamine (TEDA)from ethanolamine (MEA) with ammonia over Fe-Cu/ZSM-5 catalyst was investigated.The results showed that when Fe,Cu contents increased,the acid properties were raised,the acid amount and the conversion of MEA increased.The effective in conversion of MEA by Cu content was weaker,but evident to promte synthesis of piperazine.The reaction properties were not only influenced by the surface acid but also influenced by the properties of Fe,Cu.

  9. Electronic structure of nanosized bcc Cu precipitates in Fe-Cu alloys studied by positron 2D-ACAR

    Based on the finding with the use of the coincidence Doppler measurements that the nanosized Cu precipitates are coherently embedded in the Fe-Cu matrix alloy, taking a bcc structure and acting as efficient positron traps, we measured 2D-ACARs of carefully grown and heat treated single crystals of Fe-Cu. We found that the precipitates have a Fermi surface with 12 necks touching the {110} Bragg planes of the bcc Brillouin zone, which contrasts distinctly with that of the bulk Cu with 8 necks touching the {111} Bragg planes of the fcc Brillouin zone. The 3 dimensional momentum reconstruction of the 2D-ACAR data showed that the Fermi surface cutoff of the Cu precipitates is blurred considerably as compared with that of bulk fcc Cu, suggesting a marked size effect in the momentum distribution. (orig.)

  10. Magnetoresistive properties of multilayer film systems based on Fe/Cu and Fe/Cr

    O.V. Synashenko

    2009-01-01

    Full Text Available Magnetoresistive properties of multilayer film systems based on Fe and Cu or Cr were investigated at room temperature. Factors, which influence on the magnetoresistance (MR value change, were studied. In Fe/Cu film system, in which the individuality of separate layers holds, the substrate change from amorphous pyroceramic to monocrystalline Si(111 leads to the MR ratio increase by 35 %, that is connected with magnetic ordering in bottom epitaxial Fe layer. Thermal annealing of the samples to 700 K leads to vanishing of the odd effect in MR in perpendicular geometry and MR increase by two times in parallel geometries. Investigations of [Fe(dFe/Cr(1]10 system showed, that the Fe thickness changes from 0,31 to 1,5 nm, and this leads to the MR magnitude change from 0,03-0,05 % to 1-3 % subject to the different measurement geometries, which is interpreted by Fe granule formation in matrix of solid solution (Fe, Cr.

  11. Overlapping solid solubility in mechanically alloyed Fe-Ni and Fe-Cu

    Schilling, P. J.; Palshin, V.; Tittsworth, R. C.; He, J. H.; Ma, E.

    2003-12-01

    Solid solutions formed by mechanical alloying in the negative heat of mixing Fe-Ni system and the positive heat of mixing Fe-Cu system were studied. X-ray absorption near edge structure (XANES) spectroscopy data were analyzed to obtain the phase fractions and phase compositions for various overall compositions across the bcc/fcc two-phase region. For both systems, at each nominal composition of the powder mixture, the two solutions formed both have the same composition as the overall alloy. It is concluded that the two-phase coexistence represents an extended region of overlapping solubility for the two phases, rather than the usual two-phase region or a clear switchover at the concentration where the two phases have the same free energy. In terms of these features, the two binary systems, one with negative heat of mixing and one with positive heat of mixing, behave the same way. The external forcing action of mechanical alloying at low temperatures drives the system toward composition homogenization. There is no stable or metastable equilibrium, and the common tangent construction and lever rule are not applicable. What results is a novel two-phase coexistence which is defined by a region of overlapping solubility, rather than the normal solubility gap. That there can be two polymorphs at each composition even after the long ball-milling treatment represents a new type of steady-state two-phase coexistence that is completely different from the normal two-phase region dictated by thermodynamics.

  12. Overlapping solid solubility in mechanically alloyed Fe-Ni and Fe-Cu

    Solid solutions formed by mechanical alloying in the negative heat of mixing Fe-Ni system and the positive heat of mixing Fe-Cu system were studied. X-ray absorption near edge structure (XANES) spectroscopy data were analyzed to obtain the phase fractions and phase compositions for various overall compositions across the bcc/fcc two-phase region. For both systems, at each nominal composition of the powder mixture, the two solutions formed both have the same composition as the overall alloy. It is concluded that the two-phase coexistence represents an extended region of overlapping solubility for the two phases, rather than the usual two-phase region or a clear switchover at the concentration where the two phases have the same free energy. In terms of these features, the two binary systems, one with negative heat of mixing and one with positive heat of mixing, behave the same way. The external forcing action of mechanical alloying at low temperatures drives the system toward composition homogenization. There is no stable or metastable equilibrium, and the common tangent construction and lever rule are not applicable. What results is a novel two-phase coexistence which is defined by a region of overlapping solubility, rather than the normal solubility gap. That there can be two polymorphs at each composition even after the long ball-milling treatment represents a new type of steady-state two-phase coexistence that is completely different from the normal two-phase region dictated by thermodynamics

  13. Thermodynamics of Fe-Cu alloys as described by a classic potential

    The Fe-Cu system is of relevance to the nuclear industry because of the deleterious consequences of Cu precipitates in the mechanical properties of Fe. Several sets of classical potentials are used in molecular dynamics simulations studies of this system, in particular that proposed by Ludwig et al. [M. Ludwig, D. Farkas, D. Pedraza, S. Schmauder, Model. Simul. Mater. Sci. Eng. 6 (1998) 19]. In this work we extract thermodynamic information from this interatomic potential. We obtain equilibrium phase diagram and find a reasonable agreement with the experimental phases in the regions of relevance to radiation damage studies. We compare the results with the predicted phase diagram based on other potential, as calculated in previous work. We discuss the disagreements found between the phase diagram calculated here and experimental results, focusing on the pure components and discuss the applicability of these potentials. Improved potentials, primarily for the pure components, should be developed to account for proper phase stability in the solid phase up to melting. Finally we suggest an approach to improve existing potentials for this system

  14. Phase-field simulation of phase transformation in Fe-Cu-Mu-Ni quaternary alloy

    The phase decomposition in α(bcc) phase and the subsequent structural phase transformation from α to γ(fcc) phase during isothermal aging of an Fe-Cu-Mn-Ni quaternary alloy, which is a base alloy of the light-water reactor pressure vessel, have been simulated by the phase-field method. At the early stage of spinodal decomposition, Cu-rich α phase is formed, and the Mn and Ni, which are minor components, are partitioned to the Cu-rich phase. As the Cu composition in the precipitate is increased, the Ni atoms inside the precipitates move to the interface region between the precipitate and matrix, but Mn atoms remain inside the Cu particles. When the Cu-rich particles eventually transform to the fcc structure, the Mn atoms also move to the interface region, which results in the shell structure of the fcc Cu precipitates, where each particle is surrounded by a thin layer enriched in Mn and Ni. This microstructural change can be reasonably explained by considering the local equilibrium at the surface region of the Cu-rich particles. (author)

  15. Application of Fe-Cu binary oxide nanoparticles for the removal of hexavalent chromium from aqueous solution.

    Khan, Saif Ullah; Zaidi, Rumman; Hassan, Saeikh Z; Farooqi, I H; Azam, Ameer

    2016-01-01

    The adsorption process has been used as an effective technique for the removal of metal ions from aqueous solutions. Groundwater remediation by nanoparticles has received interest in recent years. In the present study, a binary metal oxide of Fe-Cu was prepared and used for the removal of hexavalent chromium from aqueous solution. Batch experiments were performed to investigate the effects of initial Cr (VI) concentration, dose of adsorbent, and pH of solution on the removal efficiency of Cr (VI). The prepared nanostructured Fe-Cu binary oxides were able to reduce the concentration of Cr (VI) in aqueous solution. Binary metal oxides nanoparticle exhibited an outstanding ability to remove Cr (VI) due to high surface area, low particle size, and high inherent activity. The percentage removal efficiency of Cr (VI) increased with nanoparticles doses (0.1 g L(-1)-2.5 g L(-1)), whereas it decreased with initial Cr (VI) concentration (1 mg L(-1)-25 mg L(-1)) and with pH (3-9). The Freundlich model was found to be the better fit for adsorption isotherm. The prepared nanomaterial was characterized using powder X-ray diffraction, scanning electron microscopy (SEM), and ultraviolet (UV)-visible spectroscopy. It showed that the Fe-Cu binary oxides were formed in single phase. SEM micrograph showed aggregates with many nano-sized particles. UV-visible spectroscopy showed quantum confinement effect. PMID:27386994

  16. Effect of annealing treatments on the microwave electromagnetic properties of amorphous FeCuNbSiB microwires

    Liang Di-Fei; Han Man-Gui; Yan Bo; Deng Long-Jiang

    2007-01-01

    The amorphous FeCuNbSiB microwires are fabricated by using the melt extraction method and annealed separately at temperatures T = 573, 673, 723 and 773 K for 1 h. The effect of annealing treatment on the microwave electromagnetic properties of FeCuNbSiB wires/wax composites has been investigated for the first time. It is found that in a frequency range of 0.5-4.0 GHz, the complex permittivity, permeability, magnetic and electric loss tangents of FeCuNbSiB wires/wax composites are strongly dependent on the annealing temperature and frequency. For T = 573,723 and 773K, two resonance peaks are found at frequency f = 1.2 and 3.3GHz. However, for T = 673K, only one resonance peak occurs at f = 3.3 GHz. The resonance peak at f = 1.2 GHz is believed to be due to the stress-induced anisotropy, while the resonance peak at f = 3.3 GHz is attributed to the random anisotropy.

  17. An assessment of the homogeneity of nano-crystalline Fe-Cu powders as studied by means of APT

    In this contribution the homogeneity of mechanically alloyed Fe-Cu powders for two different compositions (Fe-10 and Fe-2.5 at%Cu) has been systematically characterised by atom probe tomography. Since Fe-Cu exhibits the Invar effect, it is among the most attractive systems for technical application. Furthermore, this system is immiscible and characterised by a large positive heat of mixing. In combination with the widespread application and accessibility, this predestines Fe-Cu as a binary model alloy to elaborate the enforced nonequilibrium enhanced solubility for immiscible systems. Depending on the parameters composition and milling time, results on the extension of the solubility limit and on the homogeneity of the alloy are presented, discussed and compared to earlier works. Only for the alloy with lower Cu content and for the prolonged milling time of 50 h, chemical homogeneity of the sample as measured by the atom probe was fully reached on the nano-scale. For all other parameter combinations homogeneity could not be achieved, even for long milling times and for those samples that appear to be homogeneous via X-ray analysis. Moreover, impurities were determined, mostly stemming from the fabrication procedure. The arrangement and homogeneity of the most common impurity, oxygen, was evaluated from atom probe data for different samples. Thus, the local concentration, segregation effects and the distribution of impurities could be quantified on the nano-scale, depending on the different nominal compositions and processing parameters. Additionally, structural information could be gained employing transmission electron microscopy and diffraction measurements.

  18. Phase and particle size distribution in magnetoresistive Fe-Cu granular alloys investigated by Mössbauer spectroscopy

    Rogalski, M. S.; Pereira de Azevedo, M. M.; Sousa, J. B.

    1996-11-01

    The size distribution of ferromagnetic particles in granular Fe-Cu alloys is derived from the hyperfine field distribution of e57Fe Mössbauer spectra, on the grounds of collective magnetic excitations associated with the spectral line broadening. A good agreement with the X-ray diffraction results is found for the average particle size estimated from the Mössbauer data. The magnetoresistance of a splat-cooled Fe25Cu75 alloy reaches a maximum of 3% after appropriate annealing and its evolution is correlated with the various Fe phases (ferro, para and superparamagnetic) and particle sizes identified by the Mössbauer data.

  19. Magnetic behaviour investigation on symmetric spin valves of Co/Cu/NiFe and NiFe/Cu/Co

    李铁; 沈鸿烈

    2002-01-01

    In this paper, we have obtained and investigated the magnetic behaviours of the ferromagnetic layer in thesymmetric spin valves of Co/Cu/NiFe and NiFe/Cu/Co by measuring with a vibrating sample magnetometer andanalysing in terms of the multi-domain Ising models. It has been found that some magnetic layer can have quitedifferent magnetic behaviours in different structures of spin valves, depending on the properties of the under-layer. Inour investigation, we have found that the magnetic behaviour of a Co layer depends mainly on the magnetization of theunder-layer, whereas this is not the case for the NiFe layer.

  20. Densities of Molten and Solid Alloys of (Fe, Cu, Ni, Co)-S at Elevated Temperatures - Literature Review and Analysis

    Tesfaye, Fiseha; Taskinen, Pekka

    2010-01-01

    Densities of solid and liquid Fe, Cu, Ni and Co, and their alloys both at the presence and absence of sulfur have been reviewed. Volumetric thermal expansions were used to estimate the densities at different temperatures. Densities of the alloys generally decrease with increasing temperature. For the pure metals the reduction in density as temperature rises from 25 oC to their respective melting point can be estimated to be about 7.05 ± 0.4 % just before melting and about 11.63 ± 0.92 on comp...

  1. Recrystallization and development of cube texture in Ti and Ti+Cr added Ni-Fe-Cu alloys

    Manna, I. (Dept. of Metallurgical Engineering , I.I.T., Kharagpur (India)); Ray, R.K. (Dept. of Metallurgical Engineering, I.I.T., Kanpur (India)); Gupta, K.P. (Dept. of Metallurgical Engineering, I.I.T., Kanpur (India))

    1994-06-01

    The development of a sharp cube or [l brace]100[r brace]<100> texture in two Ti and Ti+Cr added Ni-Fe-Cu alloys is presented. Texture studies in deformed as well as recrystallized conditions have been carried out by both conventional pole figure and orientation distribution function analysis. Microstructural evolution in course of recrystallization texture development has been extensively studied with both optical and electron microscopes. Heavy cold deformation (97 to 98%) followed by annealing at 1050 C for 2 h has been found to optimize the conditions for the desired texture development. (orig.)

  2. Preparation and characterization of epitaxial thin films and patterned nanostructures of Ni/Cu and Fe/Cu

    Corredor, Edna C.

    2012-01-01

    El objetivo del trabajo realizado en esta tesis titulada: Preparation and magnetic characterization of epitaxial thin films and patterned nanostructures of Ni/Cu and Fe/Cu es establecer relaciones entre las propiedades magnéticas de sistemas nanoestructurados y sus dimensiones físicas o factores estructurales que aparecen al reducirse la dimensión espacial a dos, en el caso de películas delgadas, y a una en el caso de elementos patronados. Los sistemas objeto de estudio se caracterizan por se...

  3. Preparation and characterization of epitaxial thin films and patterned nanostructures of Ni/Cu and Fe/Cu

    Corredor Vega, Edna Consuelo; Ciria Remacha, Miguel Ángel; Arnaudas Pontaque, José Ignacio

    2013-01-01

    El objetivo del trabajo realizado en esta tesis titulada: Preparation and magnetic characterization of epitaxial thin films and patterned nanostructures of Ni/Cu and Fe/Cu es establecer relaciones entre las propiedades magnéticas de sistemas nanoestructurados y sus dimensiones físicas o factores estructurales que aparecen al reducirse la dimensión espacial a dos, en el caso de películas delgadas, y a una en el caso de elementos patronados. Los sistemas objeto de estudio se caracterizan por se...

  4. Modelling radiation-induced phase changes in binary FeCu and ternary FeCuNi alloys using an artificial intelligence-based atomistic kinetic Monte Carlo approach

    We apply a novel atomistic kinetic Monte Carlo model, which includes local chemistry and relaxation effects when assessing the migration energy barriers of point defects, to the study of the microchemical evolution driven by vacancy diffusion in FeCu and FeCuNi alloys. These alloys are of importance for nuclear applications because Cu precipitation, enhanced by the presence of Ni, is one of the main causes of hardening and embrittlement in reactor pressure vessel steels used in existing nuclear power plants. Local chemistry and relaxation effects are introduced using artificial intelligence techniques, namely a conveniently trained artificial neural network, to calculate the migration energy barriers of vacancies as functions of the local atomic configuration. We prove, through a number of results, that the use of the neural network is fully equivalent to calculating the migration energy barriers on-the-fly, using computationally expensive methods such as nudged elastic bands with an interatomic potential. The use of the neural network makes the computational cost affordable, so that simulations of the same type as those hitherto carried out using heuristic formulas for the assessment of the energy barriers can now be performed, at the same computational cost, using more rigorously calculated barriers. This method opens the way to properly treating more complex problems, such as the case of self-interstitial cluster formation, in an atomistic kinetic Monte Carlo framework.

  5. Ultrasonic slurry sampling electrothermal vaporization inductively coupled plasma mass spectrometry for the determination of Cr, Fe, Cu, Zn and Se in cereals

    Huang, Shih-Yi [Department of Chemistry, National Sun Yat-sen University, Kaohsiung 80424, Taiwan (China); Jiang, Shiuh-Jen, E-mail: sjjiang@faculty.nsysu.edu.tw [Department of Chemistry, National Sun Yat-sen University, Kaohsiung 80424, Taiwan (China); Department of Medical Laboratory Science and Biotechnology, Kaohsiung Medical University, Kaohsiung 80708, Taiwan (China); Sahayam, A.C. [National Centre for Compositional Characterisation of Materials (CCCM), Hyderabad (India)

    2014-11-01

    Ultrasonic slurry sampling electrothermal vaporization inductively coupled plasma mass spectrometry (USS-ETV-ICP-MS) has been applied to determine Cr, Fe, Cu, Zn and Se in several cereal samples. Thioacetamide was used as the modifier to enhance the ion signals. The background ions at the masses of interest were reduced in intensity significantly by using 1.0 mL min{sup −1} methane (CH{sub 4}) as reaction cell gas in the dynamic reaction cell (DRC). Since the sensitivities of Cr, Fe, Cu, Zn and Se in different matrices were quite different, standard addition and isotope dilution methods were used for the determination of Cr, Fe, Cu, Zn and Se in these cereal samples. The method detection limits estimated from standard addition curves were about 1, 10, 4, 12 and 2 ng g{sup −1} for Cr, Fe, Cu, Zn and Se, respectively, in original cereal samples. This procedure has been applied to the determination of Cr, Fe, Cu, Zn and Se whose concentrations are in μg g{sup −1} (except Cr and Se) in standard reference materials (SRM) of National institute of standards and technology (NIST), NIST SRM 1568a Rice Flour and NIST SRM 1567a Wheat Flour and two cereal samples purchased from a local market. The analysis results of reference materials agreed with certified values at 95% confidence level according to Student's T-test. The results for the real world cereal samples were also found to be in good agreement with the pneumatic nebulization DRC ICP-MS results of the sample solutions. - Highlights: • Determination of Cr, Fe, Cu, Zn and Se in cereal samples • Ultrasonic slurry sampling in combination with DRC-ICP-MS • Better sensitivity with thioacetamide modifier in ETV • Decreased sample preparation time with solid sampling • Validation with NIST SRM 1568a Rice Flour and NIST SRM 1567a Wheat Flour.

  6. Ultrasonic slurry sampling electrothermal vaporization inductively coupled plasma mass spectrometry for the determination of Cr, Fe, Cu, Zn and Se in cereals

    Ultrasonic slurry sampling electrothermal vaporization inductively coupled plasma mass spectrometry (USS-ETV-ICP-MS) has been applied to determine Cr, Fe, Cu, Zn and Se in several cereal samples. Thioacetamide was used as the modifier to enhance the ion signals. The background ions at the masses of interest were reduced in intensity significantly by using 1.0 mL min−1 methane (CH4) as reaction cell gas in the dynamic reaction cell (DRC). Since the sensitivities of Cr, Fe, Cu, Zn and Se in different matrices were quite different, standard addition and isotope dilution methods were used for the determination of Cr, Fe, Cu, Zn and Se in these cereal samples. The method detection limits estimated from standard addition curves were about 1, 10, 4, 12 and 2 ng g−1 for Cr, Fe, Cu, Zn and Se, respectively, in original cereal samples. This procedure has been applied to the determination of Cr, Fe, Cu, Zn and Se whose concentrations are in μg g−1 (except Cr and Se) in standard reference materials (SRM) of National institute of standards and technology (NIST), NIST SRM 1568a Rice Flour and NIST SRM 1567a Wheat Flour and two cereal samples purchased from a local market. The analysis results of reference materials agreed with certified values at 95% confidence level according to Student's T-test. The results for the real world cereal samples were also found to be in good agreement with the pneumatic nebulization DRC ICP-MS results of the sample solutions. - Highlights: • Determination of Cr, Fe, Cu, Zn and Se in cereal samples • Ultrasonic slurry sampling in combination with DRC-ICP-MS • Better sensitivity with thioacetamide modifier in ETV • Decreased sample preparation time with solid sampling • Validation with NIST SRM 1568a Rice Flour and NIST SRM 1567a Wheat Flour

  7. SRXRF elemental mapping and source analysis of Pb, Fe, Cu and Zn in human hair from an inhabitant in a lead-zinc mining area

    Elemental mapping of human hair may gain new insights for studying effects of mining environmental pollution on human health. SRXRF micro-analyses were conducted for longitudinal and transversal mapping of Pb, Fe, Cu and Zn relative intensities in hair sample collected from an inhabitant in Qixia lead-zinc mining area, Nanjing, Jiangsu province, China. The Pb relative intensity was low in hair follicle and root, but it increased with the hair growth. The longitudinal Pb accumulation in the hair shaft revealed a strong dependence on continuous exposure to the environment, while Fe, Cu and Zn relative intensities in the hair shaft were comparatively stable. The cortical proteins contributed to a high retention of Pb, Fe, Cu and Zn, while small quantities of all the elements but Zn were distributed in the cuticle. Medullar proteins were confirmed to contribute to slightly lower retention of Zn and Cu than cortical, but Pb and Fe were not detected in medulla. The sources of Pb in the hair were mostly exogenous contamination, and Fe, Cu and Zn were related to endogenous uptake. Zn and Cu participated in the entire metabolic process of hair growth. The study shows that SRXRF is of significance for biogeochemistry research. (authors)

  8. Seasonal variation of major elements (Ca, Mg) and trace metals (Fe, Cu, Zn, Mn) and cultured mussel Perna viridis L. and seawater in the Dona Paula Bay, Goa

    Rivonker, C.U.; Parulekar, A.H.

    The major elements and trace metals were analysed from nussel tissue and the seawater taken from three depths (0, 5 and 9 meters) from the culture site. Range of variation in Ca, Mg, Fe, Cu, Zn and Mn were 226-399; 708-1329; 0.005-0.084; BDL-0...

  9. Temperature dependence of the magnetostriction and the induced anisotropy in nanocrystalline FeCuNbSiB alloys, and their fluxgate properties

    Nielsen, Otto V; Petersen, Jan Raagaard

    1994-01-01

    Making use of the stress induced magnetic anisotropy in some iron-rich FeCuNbSiB nanocrystalline materials we studied the thermal dependence of their magnetostriction which becomes zero below the Curie temperature. The choice of a suitable composition and annealing temperature results in materials...

  10. Simultaneous determination of Ti, Cr, Fe, Cu, Ga and Zr in aluminium alloys by charged-particle activation analysis using the internal standard method

    In order to study the application of the newly developed internal standard method for charged-particle activation analysis, simultaneous determination of Ti, Cr, Fe, Cu, Ga and Zr in several commercial aluminium alloys was tried using the respective proton-induced reactions. As a result, it could be proved that the best precision and accuracy are also obtained in these determinations. (author)

  11. Effect of Sm Volatilization on Magnetic Microstructures of Sintered Sm(Co,Fe,Cu,Zr)z Magnets at High Temperatures

    XIA Ai-Lin; FANG Yi-Kun; GUO Zhao-Hui; LI Wei; HAN Bao-Shan

    2006-01-01

    @@ We present a magnetic force microscopy study of surface magnetic microstructure changes at high temperatures in 2:17-type Sm( Co, Fe, Cu,Zr)z (z ~ 7.4) magnets. Surface magnetic microstructures are found to change greatly in parallel and vertical specimens after heat-treatment at 400℃ for one hour in vacuum of 10-5 Torr with Ar gas as protecting atmosphere. Changes of microstructures are attributed to the formation of a soft-magnetic surfaces layer in the specimens, resulting from Sm volatilization due to high temperature. This hypothesis is further confirmed by the heat-treatment experiments at 400℃ for 0.5 h and 2 h. Finally, the existence of the soft-magnetic layers, which consist primarily of Fe-Co compounds, is verified by the results of both XRD and XPS of the vertical specimens before and after heat-treatment.

  12. Probing the A1 to L10 transformation in FeCuPt using the first order reversal curve method

    Dustin A. Gilbert

    2014-08-01

    Full Text Available The A1-L10 phase transformation has been investigated in (001 FeCuPt thin films prepared by atomic-scale multilayer sputtering and rapid thermal annealing (RTA. Traditional x-ray diffraction is not always applicable in generating a true order parameter, due to non-ideal crystallinity of the A1 phase. Using the first-order reversal curve (FORC method, the A1 and L10 phases are deconvoluted into two distinct features in the FORC distribution, whose relative intensities change with the RTA temperature. The L10 ordering takes place via a nucleation-and-growth mode. A magnetization-based phase fraction is extracted, providing a quantitative measure of the L10 phase homogeneity.

  13. Determination of Fe, Cu and Zn in sugar-cane spirits commercialized in Southeastern Brazil by TXRF

    Total reflection X-ray fluorescence (TXRF) was used to determine simultaneously the concentration of Cu, Fe and Zn in seven sugar-cane spirit samples ('aguardente'), a processed alcoholic beverage made from the fermentation and distillation of sugar-cane juice. The limits of detection ranged from 35 to 8 ng x ml-1 for V, Cr, Mn, Fe, Co, Ni, Cu, Zn, As and Se. Excluding Fe, Cu and Zn, the concentrations were below their limits. Two samples showed Cu concentrations higher than the value allowed by Brazilian legislation (5 μg x ml-1), and concerning Fe and Zn, no sample were above the limits permitted by WHO for drinking water (2 and 3 μg x ml-1, respectively). (author)

  14. Effects of Oral Administration of CrCl3 on the Contents of Ca, Mg, Mn, Fe, Cu, and Zn in the Liver, Kidney, and Heart of Chicken.

    Liu, Yanhan; Zhao, Xiaona; Zhang, Xiao; Zhao, Xuejun; Liu, Yongxia; Liu, Jianzhu

    2016-06-01

    This study aimed to investigate the effects of oral administration of trivalent chromium on the contents of Ca, Mg, Mn, Fe, Cu, and Zn in the heart, liver, and kidney. Different levels of 1/8, 1/4, and 1/2 LD50 (LD50 = 5000 mg/kg body mass) CrCl3 milligrams per kilogram body mass daily were added into the water to establish the chronic poisoning model. Ca, Mg, Mn, Fe, Cu, and Zn were detected with the flame atomic absorption spectrometry in the organs exposed 14, 28, and 42 days to CrCl3, respectively. Results showed that Cr was accumulated in the heart, liver, and kidney significantly (P chickens. PMID:26537118

  15. A comparative study of metabolism and concentration factors of Fe, Cu, Zn, Mn, Co and Mg in Carcinus maenas and Cancer irroratus ovaries during ovogenesis

    Fe, Cu, Zn, Mn, Co, and Mg were analysed in the ovary of Carcinus maenas and Cancer irroratus during ovogenesis. In both ovaries, the relatives rates, expressed as parts per millions as a ratio of wet and dry weight, are the following: Mg>Zn>Fe>Cu>Mn>Co, while in the hemolymph of Cancer irroratus these relative rates are the following: Mg>Cu>Zn>Fe>Mn>Co. Compared to concentrations of these metals in sea water, Mg expected, all metals in the ovary of Cancer irroratus have a concentration factor upper than 1. Compared to the concentration of metals in the hemolymph is, for Fe, Mn, and Co, the concentration factor upper than 1, and for Cu, Zn and Mg, the concentration factor lower than 1. A study of correlations was done between the concentrations of metals considered in pairs, and between the concentrations of metals and the parameters: water content and gonad index

  16. The effect of femtosecond laser micromachining on the surface characteristics and subsurface microstructure of amorphous FeCuNbSiB alloy

    Jia Wei [Ultrafast Laser Laboratory, School of Precision Instruments and Optoelectrons Engineering, Tianjin University, Tianjin 300072 (China)]. E-mail: jiaw@tju.edu.cn; Peng Zhinong [Ultrafast Laser Laboratory, School of Precision Instruments and Optoelectrons Engineering, Tianjin University, Tianjin 300072 (China); Wang Zhijun [Ultrafast Laser Laboratory, School of Precision Instruments and Optoelectrons Engineering, Tianjin University, Tianjin 300072 (China); Ni Xiaochang [Ultrafast Laser Laboratory, School of Precision Instruments and Optoelectrons Engineering, Tianjin University, Tianjin 300072 (China); Wang Chingyue [Ultrafast Laser Laboratory, School of Precision Instruments and Optoelectrons Engineering, Tianjin University, Tianjin 300072 (China)

    2006-11-30

    Detailed studies on the effects of femtosecond laser ablation on surface characteristics and subsurface microstructure of amorphous FeCuNbSiB alloy are reported. Three types of ripple structures were observed on the material surface in the gentle ablated (damaged) zone. As observed with X-ray diffraction (XRD), amorphous form is kept in the damaged zone, and there is few crystallization form in ablation zone.

  17. Determination of Mn, Fe, Cu, Zn, and Pb in particulate matter, raw and final materials of a brick factory by radionuclide X-ray fluorescence analysis

    Radionuclide X-ray fluorescence method with a Si/Li semiconductor detector and 238Pu exciting source was used in the study of Mn, Fe, Cu, Zn, and Pb content of solid emissions, raw and final materials of a brick factory. From the point of view of metal content, the working environment if the brick factory is safe for workers. (author) 2 refs.; 2 figs.; 1 tab

  18. Enthalpy of formation of quasicrystalline phase and ternary solid solutions in the Al-Fe-Cu system

    I.A. Tomilin; S.D. Kaloshkin; V. V. Tcherdyntsev

    2006-01-01

    Standard enthalpies of formation of quasicrystalline phase and the ternary solid solutions in the Al-Fe-Cu system and the intermetallic compound FeAl were determined by the means of solution calorimetry. The quasicrystalline phase was prepared using two different methods. The first method (Ⅰ) consisted of ball milling the mixture of powders of pure aluminum copper and iron in a planetary mill with subsequent compacting by hot pressing and annealing. The second method (Ⅱ) consisted of arc melting of the components in argon atmosphere followed by annealing. The latter method was used for preparing the compound FeAl and the solid solutions. The phases were identified using the XRD method. The enthalpy of the formation was determined for the quasicrystalline phase of the composition Al62Cu25.5Fe12.5 and the ternary BCC solid solutions Al35Cu14Fe51, Al40Cu17Fe43, and Al50.4Cu19.6Fe30. The measured enthalpy of formation of the intermetallic com pound FeAl is in good agreement with the earlier published data. The enthaipies of formation of the quasicrystalline phases prepared using two different methods are close to each other, namely, -22.7±3.4 (method Ⅰ) and -21.3±2.1 (method Ⅱ)k J/mol.

  19. Isothermal Kinetics Modelling of the Fischer-Tropsch Synthesis over the Spray-Dried Fe-Cu-K Catalyst

    Xiaohui Guo; Ying Liu; Jie Chang; Liang Bai; Yuanyuan Xu; Hongwei Xiang; Yongwang Li

    2006-01-01

    The isothermal kinetics of the Fischer-Tropsch synthesis (FTS) over Fe-Cu-K spray-dried catalyst was studied in a spinning basket reactor. The experiments were carried out at a constant temperature of 523 K, n(H2)/n(CO) feed ratios of 0.8-2.0, reactor pressures of 1.1-2.5 MPa, and space velocity of 0.556× 10-3 Nm3/kgcat.s. Kinetic model for hydrocarbon formation was derived on the basis of simplified carbide mechanism to reduce the number of parameters. Two individual rate constants for methane and ethene were considered. Furthermore, the model was modified empirically by non-intrinsic effect, such as physisorption and fictitious olefin pressures that were taken into account, and the influences of secondary reaction of α-olefins on product distribution. The simulation results showed that the experimental phenomena of FTS and the deviations from ASF distribution, such as the relatively high yield of methane and low yield of ethene observed experimentally could be depicted basically.

  20. Influence of alloying element of corrosion of Zr-Nb-Sn-Fe-Cu alloy and impedance characteristics of its oxide layer

    As a part of the advanced Zr fuel cladding development program, the autoclave corrosion test was performed on the series of Zr-0.2Nb-1.1Sn-Fe-Cu and Zr-0.4Nb-0.8Sn-Fe-Cu alloys in 70 ppm LiOH solution at 360 .deg. C. The oxide characteristics were investigated by using the Electrochemical Impedance Spectroscope(EIS) method. The corrosion resistance of the alloys was evaluated from the corrosion rate determined as a function of the concentration of main alloying elements such as Nb, Sn, Fe and Cu. The equivalent circuit was composed as a result of the spectrum from EIS measurements on the oxide layer that formed at pro- and post-transition regions. By using the capacitance characteristics of equivalent circuit, the thickness of impervious layer, it's electrical resistance and characteristics of space charge layer were evaluated. The corrosion characteristics of the Zr-Nb-Sn-Fe-Cu alloys were successfully explained by applying the EIS test results

  1. An insight into the metal coordination and spectroscopic properties of artistic Fe and Fe/Cu logwood inks.

    Bronzato, Maddalena; Zoleo, Alfonso; Biondi, Barbara; Centeno, Silvia A

    2016-01-15

    Fe- and Fe/Cu-based logwood inks were synthesized following recipes in nineteenth and early twentieth century manuals and were characterized by EPR, ESI-MS, FTIR, and Raman spectroscopies. This multi-technique approach allowed us to shed light on the structures of the complexes responsible for the inks' colors and to obtain vibrational signatures that can be used to identify the different inks in works of art and in historic documents. Information on the nature and chemical properties of the complexes formed between a dye and a mordant is important as these determine, at least in part, their lightfastness. EPR permitted to determine the coordination environment of the metallic ions. The results of the ESI-MS analysis demonstrated, for the first time, the breakdown of the hematein molecule during the ink preparation, and that the colorants are formed by the complexation of the metallic ions by hematein breakdown products, mainly catechol and/or bicyclic compounds. The FTIR spectra obtained were found to be dominated by bands due to the binding medium and sulfates used as reagents. The Raman analysis showed that the characteristic features for the different inks studied depend on the historic recipe used, attesting to the challenges that their identification and characterization in works of art present. In the Raman spectra of the inks applied on paper, broadening of bands in the 750-400 cm(-1) range are observed when compared to the spectra of the inks' powders, possibly due to the interaction of the compounds with the cellulose in the substrate. PMID:26414555

  2. An insight into the metal coordination and spectroscopic properties of artistic Fe and Fe/Cu logwood inks

    Bronzato, Maddalena; Zoleo, Alfonso; Biondi, Barbara; Centeno, Silvia A.

    2016-01-01

    Fe- and Fe/Cu-based logwood inks were synthesized following recipes in nineteenth and early twentieth century manuals and were characterized by EPR, ESI-MS, FTIR, and Raman spectroscopies. This multi-technique approach allowed us to shed light on the structures of the complexes responsible for the inks' colors and to obtain vibrational signatures that can be used to identify the different inks in works of art and in historic documents. Information on the nature and chemical properties of the complexes formed between a dye and a mordant is important as these determine, at least in part, their lightfastness. EPR permitted to determine the coordination environment of the metallic ions. The results of the ESI-MS analysis demonstrated, for the first time, the breakdown of the hematein molecule during the ink preparation, and that the colorants are formed by the complexation of the metallic ions by hematein breakdown products, mainly catechol and/or bicyclic compounds. The FTIR spectra obtained were found to be dominated by bands due to the binding medium and sulfates used as reagents. The Raman analysis showed that the characteristic features for the different inks studied depend on the historic recipe used, attesting to the challenges that their identification and characterization in works of art present. In the Raman spectra of the inks applied on paper, broadening of bands in the 750-400 cm- 1 range are observed when compared to the spectra of the inks' powders, possibly due to the interaction of the compounds with the cellulose in the substrate.

  3. Atom probe study of the microstructural evolution induced by irradiation in Fe-Cu ferritic alloys and pressure vessel steels

    Pressure vessel steels used in pressurized water reactors are low alloyed ferritic steels. They may be prone to hardening and embrittlement under neutron irradiation. The changes in mechanical properties are generally supposed to result from the formation of point defects, dislocation loops, voids and/or copper rich clusters. However, the real nature of the irradiation induced-damage in these steels has not been clearly identified yet. In order to improve our vision of this damage, we have characterized the microstructure of several steels and model alloys irradiated with electrons and neutrons. The study was performed with conventional and tomographic atom probes. The well known importance of the effects of copper upon pressure vessel steel embrittlement has led us to study Fe-Cu binary alloys. We have considered chemical aging as well as aging under electron and neutron irradiations. The resulting effects depend on whether electron or neutron irradiations ar used for thus. We carried out both kinds of irradiation concurrently so as to compare their effects. We have more particularly considered alloys with a low copper supersaturation representative of that met with the French vessel alloys (0.1% Cu). Then, we have examined steels used on French nuclear reactor pressure vessels. To characterize the microstructure of CHOOZ A steel and its evolution when exposed to neutrons, we have studied samples from the reactor surveillance program. The results achieved, especially the characterization of neutron-induced defects have been compared with those for another steel from the surveillance program of Dampierre 2. All the experiment results obtained on model and industrial steels have allowed us to consider an explanation of the way how the defects appear and grow, and to propose reasons for their influence upon steel embrittlement. (author). 3 appends

  4. High sensitivity zero-biased magnetic field sensor based on multiphase laminate heterostructures with FeCuNbSiB nanocrystalline soft magnetic alloy

    Qiu, Jing; Wen, Yumei; Li, Ping; Chen, Hengjia

    2016-05-01

    In this paper, a high sensitivity zero-biased magnetic field sensor based on multiphase laminate heterostructures consisting of FeCuNbSiB/Terfenol-D (Tb1-xDyxFe2)/PZT (Pb(Zr1-x,Tix)O3)/Terfenol-D/PZT/Ternol-D/FeCuNbSiB (FMPMPMF) is presented, whose ME coupling characteristics and sensing performances have been investigated. Compared to traditional Terfenol-D/PZT/Terfenol-D (MPM) and Terfenol-D/PZT/Terfenol-D/PZT/Terfenol-D (MPMPM) sensors, the zero-biased ME coupling characteristics of FMPMPMF sensor were significantly improved, owing to a build-in magnetic field in FeCuNbSiB/Terfenol-D layers. The optimum zero-biased resonant ME voltage coefficient of 3.02 V/Oe is achieved, which is 1.65 times as great as that of MPMPM and 2.51 times of MPM sensors. The mean value of low-frequency ME field coefficient of FMPMPMF reaches 122.53 mV/cm Oe, which is 2.39 times as great as that of MPMPM and 1.79 times of MPM sensors. Meanwhile, the induced zero-biased ME voltage of FMPMPMF sensor shows an excellent linear relationship to ac magnetic field both at the low frequency (1 kHz) and the resonant frequency (106.6 kHz). Remarkably, it indicates that the proposed zero-biased magnetic field sensor give the prospect of being able to applied to the field of highly sensitive ac magnetic field sensing.

  5. The mechanism of solute-enriched clusters formation in neutron-irradiated pressure vessel steels: the case of Fe-Cu model alloys

    Subbotina, A V

    2016-01-01

    Mechanism of solute-enriched clusters formation in neutron-irradiated pressure vessel steels is proposed and developed in case of Fe-Cu model alloys. We show that the obtained results are in a good agreement with available experimental data on the parameters of clusters enriched with the alloying elements. The suggested solute-drag mechanism is analogous to the well-known zone-refining process. Our model explains why the formation of solute-enriched clusters does not happen in austenitic stainless steels with fcc lattice structure. It also allows to quantify the method of evaluation of neutron irradiation dose for the process of RPV steels hardening.

  6. The mechanism of solute-enriched clusters formation in neutron-irradiated pressure vessel steels: The case of Fe-Cu model alloys

    Subbotin, A. V.; Panyukov, S. V.

    2016-08-01

    Mechanism of solute-enriched clusters formation in neutron-irradiated pressure vessel steels is proposed and developed in case of Fe-Cu model alloys. The suggested solute-drag mechanism is analogous to the well-known zone-refining process. We show that the obtained results are in good agreement with available experimental data on the parameters of clusters enriched with the alloying elements. Our model explains why the formation of solute-enriched clusters does not happen in austenitic stainless steels with fcc lattice structure. It also allows to quantify the method of evaluation of neutron irradiation dose for the process of RPV steels hardening.

  7. Probing the Structure, Stability and Hydrogen Adsorption of Lithium Functionalized Isoreticular MOF-5 (Fe, Cu, Co, Ni and Zn by Density Functional Theory

    Yoshiyuki Kawazoe

    2009-04-01

    Full Text Available Li adsorption on isoreticular MOFs with metal Fe, Cu, Co, Ni and Zn was studied using density function theory. Li functionalization shows a considerable structural change associated with a volume change in isoreticular MOF-5 except for the Zn metal center. Hydrogen binding energies on Li functionalized MOFs are seen to be in the range of 0.2 eV, which is the desired value for an ideal reversible storage system. This study has clearly shown that Li doping is possible only in Zn-based MOF-5, which would be better candidate to reversibly store hydrogen.

  8. Force-sensitive properties of FeCuNbSiB powder/butyl rubber composite films%FeCuNbSiB非晶粉体/丁基橡胶复合薄膜的力敏特性

    周佳; 朱正吼; 付远; 乔宝英; 杜康

    2014-01-01

    Composite film was prepared by molding method with amorphous Fe73.5 Cu1 Nb3 Si13.5 B9 powder as compound phase and butyl rubber as matrix phase.The particle size was 45μm,the content of powder was 85%and the thickness of film was 150 or 200μm.LYYL-500N high-grade type microcomputer control pressure tes-ting machine was used to conduct program control loading with speed of 0.1,0.5 and 1.0 mm/min.Values of impedance,Z,under pressure stress were measured by TH2816LCR digital bridge with 1 and 50 kHz.The pa-per study the effect of loading speed,testing frequency,film thickness and testing temperature on force-sensi-tive properties.The results show the force-sensitive stability property was best,when the loading speed was 0. 1 mm/min.The sensitivity (|k|)of composite films increase firstly then decrease with the increasing stress during loading process,while it increase with the decreasing stress during uploading process.While the fre-quency was 1 kHz,the force-sensitive sensitivity of composite films are better than 50 kHz.The force-sensitive sensitivity of 200μm process are superior to 150μm.The higher temperature is,the better sensitivity of com-posite film is.%以粒径为45μm 的 Fe73.5 Cu1 Nb3 Si13.5 B9非晶粉体为复合相,丁基橡胶为基体相,利用模压成型法制备了粉体含量为85%、厚度为150和200μm 的复合薄膜。采用LYYL-500N高档型微机控制压力试验机对薄膜试样进行连续加载/卸载实验(速度分别为0.1,0.5和1.0 mm/min),用 TH2816LCR 数字电桥测试频率1和50 kHz下薄膜的阻抗Z 值。研究了加载/卸载速度、测试频率、薄膜厚度和环境温度对 Fe-CuNbSiB粉体/丁基橡胶力敏特性的影响。研究表明,复合薄膜在v=0.1 mm/min 时,其重复性最好,在加载过程中,应力灵敏度|k|值随着应力的增大呈现先增大后减小的变化趋势,卸载过程中,|k|值随着应力的逐渐减小而增大。在1 kHz测试频率下复合薄膜的力敏灵敏度高于50 k

  9. Understanding of copper precipitation under electron or ion irradiations in FeCu0.1 wt% ferritic alloy by combination of experiments and modelling

    This work is dedicated to the understanding of the basic processes involved in the formation of copper enriched clusters in low alloyed FeCu binary system (FeCu0.1 wt%) under irradiation at temperature close to 300 deg. C. Such an alloy was irradiated with electrons or with ions (Fe+ or He+) in order to deconvolute the effect of displacement cascades and the associated generation of point defect clusters (ion irradiations), and the super-saturation of mono-vacancies and self-interstitial atoms (electron irradiation). The microstructure of this alloy was characterised by tomographic atom probe. Experimental results were compared with results obtained with cluster dynamic model giving an estimation of the evolution of point defects (free or agglomerated) under irradiation on the one hand and describing homogeneous enhanced precipitation of copper on the other hand. The comparison between the results obtained on the different irradiation conditions and the model suggests that the point defect clusters (dislocation loops and/or nano-voids) created in displacement cascades play a major role in copper clustering in low copper alloy irradiated at 573 K

  10. Structure, grain connectivity and pinning of as-deformed commercial MgB2 powder in Cu and Fe/Cu sheaths

    Single-core MgB2 wires and tapes have been made by the powder-in-tube (PIT) method using commercial MgB2 powder (Alfa Aesar). Composites have been made using the two-axial rolling process in Cu and/or Fe/Cu sheaths. Alternative deformations by wire drawing, rotary swaging and cold isostatic pressing have been applied to PIT wires and tapes. Current-voltage characteristics and transport current densities in the self-field and in the external field were measured. It was found that the grain connectivity of ex situ MgB2 is affected by the applied sheath and the mode of deformation. Two-axial rolling has generated the highest powder density resulting in the best grain connectivity. The highest transport current densities of 8700 A cm-2 and 55 830 A cm-2 were measured for Cu and Fe/Cu sheathed square wires, respectively. Cold isostatic pressing at 1.5 GPa has increased current density and n-exponent, which suggests an improvement in grain connectivity. It was found that the external pressure improves the inter-grain connectivity but decreases the pinning in MgB2 cores. (author)

  11. Models of Al-, Fe-, Cu- and Zr-alloys corrosion based on thermodynamic estimates of corrosion product solubilities in water coolants of nuclear power units

    In this report an effort is made to provide thermodynamic explanation of the data on the corrosion of Fe-, Cu-, Zr- and Al-based construction materials in water-cooled circuits of NPPs at concrete water chemistry conditions. Physicochemical models of corrosion in chemically desalinized water are also presented using a complete set of equilibrium conditions in the system CPs - water coolant. At the 1st stage of the problem solution the solubility was defined for the system 'corrosion products (MenOm; Me(OH)k)) - water (H2O) - gas (H2, O2) - additives (HCl, KOH) for pH correction' in the range of 25-350degC. The 2nd stage of our work includes the formation of the database on the kinetics and rate of metal corrosion in water - parabolic uniform process for Fe-, Cu- and Al-alloys; linear 'post-transitional' process for Zr-alloys. The results obtained allow to establish a correlation between the corrosion parameters and the equilibrium solubility of that phase of CPs which remains stable during corrosion tests. (author)

  12. Crystal structure and Moessbauer spectroscopy of Y2SrFeCuO6.5, a double layer perovskite intergrowth phase

    The crystal structure of Y2SrFeCuO6.5 was determined from single-crystal X-ray and neutron powder diffraction studies. Mr = 488.81, orthorhombic, Ibam, a = 5.4036(8)[5.4149(1)] angstrom, b = 10.702(1)[10.7244(1)] angstrom, c = 20.250(2)[20.2799(2)] angstrom; values in square brackets are neutron data. V = 1171.0(4), Z = 8, Dx = 5.544 g cm-3, λ = 0.71069 angstrom, μ = 345.1 cm-1, R = 0.048 for 567 observed reflections. The Fe/Cu atoms occupy randomly the approximate center of oxygen pyramids. The pyramids share the apical oxygen and articulate laterally by corner sharing of oxygen to form a double pyramidal layer perpendicular to c. The pyramidal slabs are separated by double layers of Y that are in 7-fold coordination to oxygen, forming a defect fluorite unit. Moessbauer spectra indicate a unique iron environment and magnetic ordering at about 265 K. The paramagnetic phase coexists with the magnetic phase over an approximate temperature range 300-263 K, characteristic of magnetic ordering in 2-D magnetic structures

  13. Experimental investigation of inhomogeneities, nanoscopic phase separation, and magnetism in arc melted Fe-Cu metals with equal atomic ratio of the constituents

    Hassnain Jaffari, G.

    2015-12-16

    Composition gradient and phase separation at the nanoscale have been investigated for arc-melted and solidified with equiatomic Fe-Cu. Diffraction studies revealed that Fe and Cu exhibited phase separation with no trace of any mixing. Microscopy studies revealed that immiscible Fe-Cu form dense bulk nanocomposite. The spatial distribution of Fe and Cu showed existence of two distinct regions, i.e., Fe-rich and Cu-rich regions. Fe-rich regions have Cu precipitates of various sizes and different shapes, with Fe forming meshes or channels greater than 100 nm in size. On the other hand, the matrix of Cu-rich regions formed strips with fine strands of nanosized Fe. Macromagnetic response of the system showed ferromagnetic behavior with a magnetic moment being equal to about 2.13 μB/Fe atom and a bulk like negligible value of coercivity over the temperature range of 5–300 K. Anisotropy constant has been calculated from various laws of approach to saturation, and its value is extracted to be equal to 1350 J/m3. Inhomogeneous strain within the Cu and Fe crystallites has been calculated for the (unannealed) sample solidified after arc-melting. Annealed sample also exhibited local inhomogeneity with removal of inhomogeneous strain and no appreciable change in magnetic character. However, for the annealed sample phase separated Fe exhibited homogenous strain.

  14. Transmission Mössbauer spectroscopy and x-ray diffraction studies on the structure of nanocrystalline Fe-Cu-Si-B alloys

    Liu, X. D.; Lu, K.; Hu, Z. Q.; Ding, B. Z.; Zhu, J.; Jiang, J.

    1994-04-01

    Nanocrystalline Fe-Cu-Si-B alloys with grain sizes of 25-90 nm were synthesized by crystallization of the amorphous alloy. Two nanocrystalline phases of α-Fe(Si) and Fe2B were observed in all tested samples. Transmission Mössbauer spectroscopy investigation on the structure of nanocrystalline Fe-Cu-Si-B alloys showed that Si atoms are completely and substitutionally dissolved in Fe bcc lattice and the arrangement of the Si atoms in the α-Fe(Si) phase shows short range order (SRO), whereas 8.5-9.7 at. % of the B atoms were found as Fe2B and the remainder were located in the interfaces. When grains grow larger, the arrangement of the Si atoms in the α-Fe(Si) phase changes. Interestingly, x-ray diffraction results reveal that the lattice constant of α-Fe(Si) phase decreases rapidly with grain coarsening. Based on the thermodynamic analysis, the changes in the lattice constant of the α-Fe(Si) phase and SRO of Si atoms in bcc Fe lattices were attributed to the lattice expansion as a result of the variation of vacancy concentration in α-Fe(Si) solid solution. Meanwhile, owing to the interface contribution, the alloy with small grain size is found to exhibit large values of half linewidth (HLW) and isomer shift (IS) in the Mössbauer spectra. The results from electrical resistivity measurements agree and confirm the strong effects of the lattice distortion and interfaces.

  15. Experimental investigation of inhomogeneities, nanoscopic phase separation, and magnetism in arc melted Fe-Cu metals with equal atomic ratio of the constituents

    Hassnain Jaffari, G.; Aftab, M.; Anjum, D. H.; Cha, Dongkyu; Poirier, Gerald; Ismat Shah, S.

    2015-12-01

    Composition gradient and phase separation at the nanoscale have been investigated for arc-melted and solidified with equiatomic Fe-Cu. Diffraction studies revealed that Fe and Cu exhibited phase separation with no trace of any mixing. Microscopy studies revealed that immiscible Fe-Cu form dense bulk nanocomposite. The spatial distribution of Fe and Cu showed existence of two distinct regions, i.e., Fe-rich and Cu-rich regions. Fe-rich regions have Cu precipitates of various sizes and different shapes, with Fe forming meshes or channels greater than 100 nm in size. On the other hand, the matrix of Cu-rich regions formed strips with fine strands of nanosized Fe. Macromagnetic response of the system showed ferromagnetic behavior with a magnetic moment being equal to about 2.13 μB/ Fe atom and a bulk like negligible value of coercivity over the temperature range of 5-300 K. Anisotropy constant has been calculated from various laws of approach to saturation, and its value is extracted to be equal to 1350 J/m3. Inhomogeneous strain within the Cu and Fe crystallites has been calculated for the (unannealed) sample solidified after arc-melting. Annealed sample also exhibited local inhomogeneity with removal of inhomogeneous strain and no appreciable change in magnetic character. However, for the annealed sample phase separated Fe exhibited homogenous strain.

  16. Continuous Bulk FeCuC Aerogel with Ultradispersed Metal Nanoparticles: An Efficient 3D Heterogeneous Electro-Fenton Cathode over a Wide Range of pH 3-9.

    Zhao, Hongying; Qian, Lin; Guan, Xiaohong; Wu, Deli; Zhao, Guohua

    2016-05-17

    Novel iron-copper-carbon (FeCuC) aerogel was fabricated through a one-step process from metal-resin precursors and then activated with CO2 and N2 in environmentally friendly way. The activated FeCuC aerogel was applied in a heterogeneous electro-Fenton (EF) process and exhibited higher mineralization efficiency than homogeneous EF technology. High total organic carbon (TOC) removal of organic pollutants with activated FeCuC aerogel was achieved at a wide range of pH values (3-9). The chemical oxygen demand (COD) of real dyeing wastewater was below China's discharge standard after 30 min of treatment, and the specific energy consumption was low (9.2 kW·h·kg(-1)COD(-1)), corresponding to a power consumption of only ∼0.34 kW·h per ton of wastewater. The enhanced mineralization efficiency of FeCuC aerogel was mostly attributable to ultradispersed metallic Fe-Cu nanoparticles embedded in 3D carbon matrix and the CO2-N2 treatment. The CO2 activation enhanced the accessibility of the aerogel's pores, and the secondary N2 activation enlarged the porosity and regenerated the ultradispersed zerovalent iron (Fe(0)) with reductive carbon. Cu(0) acted as a reduction promoter for interfacial electron transfer. Moreover, activated FeCuC aerogel presented low iron leaching (<0.1 ppm) in acidic solution and can be molded into different sizes with high flexibility. Thus, this material could be used as a low-cost cathode and efficient heterogeneous EF technology for actual wastewater treatment. PMID:27082750

  17. Determination of total proteins and lipids, ash, humidity, macro (Ca, Mg, K) and micro (Fe, Cu, Mn, Zn) elements in varieties of soybeans [Glycine Max (L.) Merrill] not transgenics and transgenics

    Dimas Augusto Morozin Zaia; Cristiane Novacki; Neide Kiyoko Kondo Kamizake

    2006-01-01

    In the present paper three strains (EMBR-59, BRS-133, BRS-137) of soybean [Glycine Max (L.) Merrill] with their transgenic varieties (EMBR-59-RR, BRS-133-RR, BRS-137-RR), were analyzed. The following determinations were carried out in all samples: total proteins and lipids, ash, humidity, macro (Ca, Mg, K) and micro (Fe, Cu, Mn, Zn) elements. The results showed that the concentrations of total proteins, Ca, Mg, Fe, Cu, and Mn in all samples were not statistically different among themselves (S...

  18. Iron Oxide-Supported Copper Oxide Nanoparticles (Nanocat-Fe-CuO): Magnetically Recyclable Catalysts for the Synthesis of Pyrazole Derivatives, 4-Methoxyaniline, and Ullmann-type Condensation Reactions

    An efficient and benign protocol is reported for the synthesis of 4-methoxyaniline, medicinally important pyrazole derivatives, and Ullmann-type condensation reaction using magnetically separable and reusable magnetite-supported copper (nanocat-Fe-CuO) nanoparticles under mild co...

  19. Structural relaxation and crystallisation processes in FeCu1XSi13B9 (X=Mo, Cr, Zr) amorphous alloys

    The main aim of the paper was to study the influence of 1 h annealing (temperature range 300aa) and magnetic permeability μ(Ta) determined at room temperature. The observed dependence of Δμ/μ (Ta) is in agreement with models proposed by Allia- Vinai and Kronmueller and can be related to processes of coagulation and disappearance of microvoids (the intensity of magnetic after-effect is proportional to the amount of microvoids). It has been shown that for the amorphous alloys of type FeCu1XSi13B9 (X=Mo, Cr, Zr) magnetic properties can be optimised by applying the well-defined thermal treatment causing a formation of nanocrystalline phase

  20. Investigation of the structure and properties of the titanium alloy of the Ti-Al-Mo-V-Fe-Cu-Zr-Sn system

    The alloys of martensitic type in the Ti-Al-Mo-V-Fe-Cu-Zr-Sn system after heat treatment are investigated. To determine the composition of the titanium alloy methods of mathematical planning of the experiment are applied. Results of mechanical tests of the alloys are presented, as well as coefficients of models for the properties, calculated according to these data. The investigation establishes the composition of a high-strength titanium alloy of a martensitic type, containing 4.5-60 % Al, 2.0-4.0 % Mo, 0.5-1.9 % V, 0.3-1.5 % Fe, 0.3-1.5 % Cu, 1.5-3.0 % Sn, 2.0-4.0 % Zr. The semiproducts, produced by deformation in β-field, after heat treatment have an ultimate strength >=120 kg/mm2, satisfactory ductility and reliability. The alloy possesses rather a high heat resistance and can be operated at 400-500 deg C

  1. Evaluation of the heavy metals Cr, Mn, Fe, Cu, Zn and Pb in water penny wort (Hydrocotyle ranunculoides) from the upper course of the Lerma River, Mexico

    The Lerma river is one of the most polluted water bodies in Mexico, it presents low biodiversity and lets grow up aquatic plants resistant to the pollution. The aim of this work was to evaluate the concentration and bioaccumulation factors of Cr, Mn, Fe, Cu, Zn and Pb in aerial and submerged structures of water penny wort (Hydrocotyle ranunculoides) from the upper course of the Lerma river. Inductively coupled plasma-optical emission spectrometry was used to determine the concentration of heavy metals in water and H. ranunculoides. Results show that the bioaccumulation factors of Fe and Zn were higher than those of Cu, Mn, Cr and Pb; with the exception of Zn, bioaccumulation factors were higher in the submerged structures of the plant, which shows low mobility of analyzed metals. As a result of this study H. ranunculoides can be considered as good indicator of metal pollution in water bodies. (Author)

  2. Structural properties of amorphous and nanocrystallized Fe-Cu-Nb-Si-B and Fe-Gd-Cu-Nb-Si-B ribbons

    The influence of Gd addition on the structural properties of Fe-Cu-Nb-Si-B nanocrystallized and amorphous alloys is studied. The crystallization temperature increases and the microstructure of the annealed samples changes. Gd addition induces the formation of Gd-Fe-B phases. In fully crystallized Fe-Gd-Cu-Nb-Si-B alloys the α-Fe(Si), Fe-Nb-B, Gd3Fe62B14 and Gd1.1Fe4B4 phases are observed. The evolution of the microstructure is followed as a function of the cumulative effects of annealing time and temperature. The results suggest the transformation of the metastable Gd3Fe62B14 phase into Gd1.1Fe4B4 and α-Fe. The hyperfine parameters of the Gd3Fe62B14 Moessbauer contribution are reported. (orig.)

  3. Determination of total proteins and lipids, ash, humidity, macro (Ca, Mg, K and micro (Fe, Cu, Mn, Zn elements in varieties of soybeans [Glycine Max (L. Merrill] not transgenics and transgenics

    Dimas Augusto Morozin Zaia

    2006-02-01

    Full Text Available In the present paper three strains (EMBR-59, BRS-133, BRS-137 of soybean [Glycine Max (L. Merrill] with their transgenic varieties (EMBR-59-RR, BRS-133-RR, BRS-137-RR, were analyzed. The following determinations were carried out in all samples: total proteins and lipids, ash, humidity, macro (Ca, Mg, K and micro (Fe, Cu, Mn, Zn elements. The results showed that the concentrations of total proteins, Ca, Mg, Fe, Cu, and Mn in all samples were not statistically different among themselves (Student-Newman-Keuls-SNKp>0.05. The concentrations of total lipids, humidity, ash and K were statistically different (SNKp0.05. The concentration of Zn showed values statistically different (SNKp<0.05 between BRS-137 and its transgenic variety BRS-137-RR.

  4. Changes of Fe matrix lattice constant during liquid phase sintering of Fe-Cu-C compacts by x-ray diffraction techniques

    The dissolution of graphite and copper during sintering of PM steels prepared from iron, copper and graphite powder mixes were studied using X-Ray Diffraction method. This paper present the investigation carried out to study the changes of iron's lattice constant during liquid phase sintering of the compacts. The electrical conductivity measurement method was also used for determining the extent of carbon and copper dissolution and its influence on the formation of sintered compacts. In the experiment, the Fe-Cu-C powders were compacted into a pellets using hand press machine and were then sintered in a 5% H2 + 95% N2 gas atmosphere at different sintering temperature in the range of 400 degree C and 1200 degree C. The effect of sintering parameters on the mechanical properties of the sintered compacts was studied to find a correlation between mechanical behaviour, microstructure, and the resistivity in order to develop nondestructive testing method. It was observed that measurement of Fe matrix lattice constant and electrical conductivity of sintered compacts could be a viable method in studying all stages of sintering process. (Author)

  5. Formation of oxide nanotubes via oxidation of Fe, Cu and Ni nanowires and their structural stability: Difference in formation and shrinkage behavior of interior pores

    Nakamura, R., E-mail: rnakamur@sanken.osaka-u.ac.jp [Institute of Scientific and Industrial Research, Osaka University, Mihogaoka 8-1, Ibaraki, Osaka 567-0047 (Japan); Matsubayashi, G. [Institute of Scientific and Industrial Research, Osaka University, Mihogaoka 8-1, Ibaraki, Osaka 567-0047 (Japan); Tsuchiya, H.; Fujimoto, S. [Division of Materials and Manufacturing Science, Graduate School of Engineering, Osaka University, 2-1 Yamada-oka, Suita, Osaka 565-0871 (Japan); Nakajima, H. [Institute of Scientific and Industrial Research, Osaka University, Mihogaoka 8-1, Ibaraki, Osaka 567-0047 (Japan)

    2009-10-15

    Changes in the morphology of Fe, Cu and Ni nanowires with a diameter of 55 nm during oxidation at 423-923 K were studied by transmission electron microscopy. Oxide nanotubes with a cylindrical interior pore of uniform diameter were formed after the oxidation of Fe and Cu nanowires in air at 573 and 423 K, respectively, while the Ni nanowires became bamboo-like nanowires of NiO with separate interior voids after oxidation at 673-773 K. Oxide nanotubes of Fe and Cu and the bamboo structures of NiO showed a tendency to shrink into solid oxide nanowires after annealing at higher temperatures in air. In the shrinking process of Fe{sub 3}O{sub 4} nanotubes, however, an array of additional nanovoids was observed along the inner wall of the nanotubes, suggesting the formation of a duplex porous nanostructure. This can be explained by the recombination of vacancies diffusing outward from the inner cylindrical pore.

  6. Sodium, K, Ca, Mg, Fe, Cu, and Zn concentrations in molluscs from the Magellan Strait (Chile): their contribution to dietary intake.

    España, M S Astorga; Rodríguez, E M Rodríguez; Romero, C Díaz

    2005-08-01

    The concentrations of the essential metals Na, K, Ca, Mg, Fe, Cu, and Zn were determined in 126 specimens of molluscs belonging to five different species: Mytilus chilensis, n=47; Nacella deaurata, n=65; Aulacomya ater, n=4; Fissurella picta, n=4; Acanthina monodon, n=6, collected from the coastline of the Magellan Strait. Significant differences were obtained among the mean metal concentrations in the mollusc species considered. The contribution to the dietary daily intake of these metals for the consumption of one serving of these molluscs was high, especially the contribution to the Fe intake for the consumption of N. deaurata. Some significant differences were observed among the mean concentrations for the studied metals according to the zone of sampling. The influence of the zone of sampling on the mean concentration of metals in N. deaurata was higher than in M. chilensis. The application of lineal discriminant analysis (LDA) made it possible to differentiate statistically between specimens according to the mollusc species. Within the each mollusc species, the LDA helped to identify specimens according to the zone of sampling and weight/length ratio. PMID:16236595

  7. Optimisation of soft magnetic properties in Fe-Cu-X-Si13B9 (X=Cr, Mo, Zr) amorphous alloys

    In the present paper a group of Fe-Cu-X-Si13B9 (X=Cr, Mo, Zr) amorphous alloys has been examined by applying different experimental techniques--magnetic permeability, magnetic after-effect, coercive force and electrical resistivity measurements. It has been shown that their soft magnetic properties can be optimised by 1-h thermal annealing at the temperature close to the crystallisation temperature. This leads to an increase of permeability and a decrease of coercive force, thermal instability (magnetic after-effect intensity) and electrical resistivity of the material. The optimisation effect is discussed in terms of different processes--(i) a formation of a nanocrystalline phase with the grain size much smaller than the ferromagnetic exchange length, (ii) an annealing out of microvoids formed during the fabrication process and also (iii) a decrease of the effective magnetostriction constant. The temperature of optimisation annealing treatment is always higher than the Curie temperatures of the materials and varies approximately linearly with the atomic radius of the alloying additions

  8. High-sensitivity planar Hall sensor based on simple gaint magneto resistance NiFe/Cu/NiFe structure for biochip application

    The planar Hall effect (PHE) sensor based on a simple giant magneto resistance (GMR) trilayer structure NiFe/Cu/NiFe has been designed and fabricated successfully using conventional clean room fabrication methods. The PHE sensor is integrated by 24 sensor patterns with dimensions of 50 × 50 μm. Influence of individual layer thickness to sensitivity of sensor has been investigated. Sensitivity and planar Hall voltage increases with the decrease of Cu-layer thickness. The results are discussed in terms of the reinforcement of the antiferromagnetic interaction between NiFe layers and shunting current through the layer Cu. The optimum configuration has been found in the structure with the Cu-layer of 1 nm. In this case a single planar Hall effect sensor exhibits a high sensitivity of about 8 μV Oe−1 and a maximal of the signal change as large as ▵V ∼ 55 μV. These values are comparable to those of the typical PHE sensor based on complex GMR spin-valve structure. With a high sensitivity and simple structure, this sensor is very promising for practical detection of magnetic beads and identifying multiple biological agents in the environment. (paper)

  9. Evaluation of the heavy metals Cr, Mn, Fe, Cu, Zn and Pb in water penny wort (Hydrocotyle ranunculoides) from the upper course of the Lerma River, Mexico; Evaluacion de los metales pesados Cr, Mn, Fe, Cu, Zn y Pb en sombrerillo de agua (Hydrocotyle ranunculoides) del curso alto del Rio Lerma, Mexico

    Zarazua, G.; Avila P, P.; Tejeda, S. [ININ, Carretera Mexico-Toluca s/n, 52750 Ocoyoacac, Estado de Mexico (Mexico); Valdivia B, M.; Macedo M, G. [Instituto Tecnologico de Toluca, Av. Tecnologico s/n, Ex-Rancho La Virgen, 52140 Metepec, Estado de Mexico (Mexico); Zepeda G, C., E-mail: graciela.zarazua@inin.gob.mx [Universidad Autonoma del Estado de Mexico, Cerro de Coatepec s/n, Ciudad Universitaria, 50100 Toluca, Estado de Mexico (Mexico)

    2013-07-01

    The Lerma river is one of the most polluted water bodies in Mexico, it presents low biodiversity and lets grow up aquatic plants resistant to the pollution. The aim of this work was to evaluate the concentration and bioaccumulation factors of Cr, Mn, Fe, Cu, Zn and Pb in aerial and submerged structures of water penny wort (Hydrocotyle ranunculoides) from the upper course of the Lerma river. Inductively coupled plasma-optical emission spectrometry was used to determine the concentration of heavy metals in water and H. ranunculoides. Results show that the bioaccumulation factors of Fe and Zn were higher than those of Cu, Mn, Cr and Pb; with the exception of Zn, bioaccumulation factors were higher in the submerged structures of the plant, which shows low mobility of analyzed metals. As a result of this study H. ranunculoides can be considered as good indicator of metal pollution in water bodies. (Author)

  10. Influência dos Íons Mg, Ca, Fe, Cu e Zn sobre a tensão superficial estática de soluções contendo surfatante Influence of Mg, Ca, Fe, Cu and Zn Ions on static surface tension of surfactant solutions

    F.M.L. Silva

    2006-09-01

    Full Text Available O objetivo do estudo foi avaliar a influência da presença de cinco íons em uma calda de pulverização contendo o surfatante Aterbane. A tensão superficial foi analisada por meio da medição da massa de um conjunto de 25 gotas, com quatro repetições constituindo um tratamento. O trabalho foi dividido em duas etapas. Na primeira, os tratamentos foram combinados em esquema fatorial 9x5x2, sendo nove concentrações do surfatante Aterbane (0,01; 0,025; 0,05; 0,1; 0,2; 0,5; 1; 2; e 3%, cinco íons (Mg++, Ca++, Fe+++, Cu+++ e Zn+++ e duas concentrações desses elementos (10 e 100 ppm. Na segunda etapa, os tratamentos foram combinados em esquema fatorial 5x5x1, utilizandose os mesmos cinco elementos (Mg++, Ca++, Fe+++, Cu+++ e Zn+++, em cinco concentrações (1, 5, 20, 50 e 200 ppm, com apenas uma concentração do surfatante Aterbane (0,025%. Outros nove tratamentos permitiram avaliar as tensões superficiais das concentrações do surfatante (0,01; 0,025; 0,05; 0,1; 0,2; 0,5; 1; 2; e 3% sem a adição dos íons. Os resultados mostraram que houve interferência dos íons sobre as soluções, já que, com exceção do Fe+++ (na concentração de 10 e 100 ppm e do Cu+++ (na concentração de 100 ppm, todos os íons reduziram a tensão mínima alcançada e aumentaram a eficiência do surfatante, implicando benefícios à ação do surfatante e sobre as características de possíveis soluções de aplicação. Todos os íons avaliados promoveram reduções nas tensões superficiais de soluções do surfatante na concentração de 0,025%.The objective of this study was to evaluate the influence of 5 ions on a spray solution containing the surfactant aterbane. Surface tension was analyzed by measuring the mass of a set of 25 drops, with four repetitions constituting a treatment. The work was divided in two stages. In the first, the treatments were arranged in a 9x5x2 factorial design, nine Aterbane concentrations (0.01; 0.025; 0.05; 0.1; 0.2; 0

  11. Characteristics of melt inclusions in skarn minerals from Fe,Cu(Au) and Au(Cu) ore deposits in the region from Daye to Jiujiang

    ZHAO; Bin; (赵斌); ZHAO; Jinsong; (赵劲松); LI; Zhaolin; (李兆麟); ZHANG; Zhongze; (张重泽); PENG; Zhuolun; (彭卓伦)

    2003-01-01

    A vast amount of the melt inclusions and fluid-melt inclusions have been found in skarn minerals from Fe, Cu(Au) and Au(Cu) ore deposits distributed from Daye to Jiujiang along the Yangtze River besides vapor-liquid inclusions. The melt inclusions are many and varied in shape. They mainly consist of crystallized silicate phases (CSi), iron phases (Fe), amorphous silicate phases (ASi) and vapor (V) with different volume percentages, and some of them contain several crystallized silicate phases. These melt inclusion sizes are commonly (10-46)×(6-15) μm2. A difference between the fluid-melt inclusions and melt inclusions is that the liquid phase appears in the former and their homogenization temperatures are lower than the latter. We measured the homogenization temperatures of the melt inclusions, fluid-melt inclusions and fluid inclusions in ten thin sections from eight ore deposits on Leitz microscope heating stage 1350 which was made in Germany. Forty-eight homogenization temperature values have been obtained. Among them, thirty-nine values are homogenization temperatures of the melt inclusions in garnet and pyroxene from skarns, two values are homogenization temperatures of fluid-melt inclusions, others belong to the fluid inclusions. Melt inclusions in garnet and pyroxene have homogenization temperatures of 890-1115℃. Fluid-melt inclusions have homogenization temperatures of 745-750℃. Homogenization temperatures of fluid inclusions are between 580℃ and 675℃. The average of thirty- nine homogenization temperatures for the melt inclusions is 1029.9℃. Wethink studied skarns to be magmatic genesis on the basis of available data relative to the characteristic features of phase states within the melt inclusions and the fluid melt inclusions and their homogenization temperatures.

  12. Positive feedback between strain localization and fluid flow at the ductile-brittle transition leading to Pb-Zn-Fe-Cu-Ag ore deposits in Lavrion (Greece)

    Scheffer, Christophe; Tarantola, Alexandre; Vanderhaeghe, Olivier

    2016-04-01

    At the crustal scale, the ductile-brittle transition (DBT) might correspond to a physical barrier that separates a deep reservoir of metamorphic and magmatic fluids from a shallow reservoir of surficial fluids. Rock rheology, and thus the location of the DBT, is mainly governed by lithology, temperature and the presence/absence of fluids. Accordingly, the position of the DBT potentially evolves during orogenic evolution owing to thermal evolution and fluid circulation. In turn rocks are transferred across it during burial and exhumation. These processes induce connections between fluid reservoirs which might play a role on ore deposition. In this contribution, we discuss the impact of lithological heterogeneities on deformation, fluid flow and ore deposition based on the example of the Lavrion low-angle top-to-the-SSW detachment accommodating gravitational collapse of the Hellenides orogenic belt in Greece. The Lavrion peninsula, localized along the western boundary of the Attic-Cycladic Metamorphic Core Complex, is characterized by Pb-Zn-Fe-Cu-Ag ore mineralization mainly concentrated along a lithological contact (marble/schists) below and within a detachment shear zone. The mylonitic marble below the detachment shear zone is composed of white layers of pure marble alternating with blue layers containing impurities (SiO2, Al2O3, organic matter…). Development of the mylonitic fabric in competent impure blue marble is associated with its preferred dolomitization related to focused fluid infiltration. This mylonitic marble is cross-cut by several cataclastic horizons preferentially developed within the more competent impure blue marble and newly-crystallized dolomitic horizon. These cataclasites are invaded by fluorite and calcite gangue minerals showing locally Mn, Pb, Zn, Fe oxides and/or hydroxides, sphalerite, Ag-galena, Ag-sulfur and native Ag. Oxygen and carbon stable isotopes performed on marble sections point out decarbonation with magmatic contribution and

  13. Preparation and catalytic property of catalyst in Fe-Cu-Ce/Al2O3 heterogeneous fenton reaction%Fe-Cu-Ce/Al2O3非均相Fenton催化剂的制备及活性研究

    关晓雨; 崔宝臣; 丁龙; 王彧

    2014-01-01

    采用浸渍法制备Fe-Cu-Ce/Al2O3催化剂,探讨了催化剂的制备条件、初始pH值等因素对催化剂活性的影响.研究结果表明:Fe、Cu、Ce总离子浓度0.05 mol/L,n(Fe)∶n(Cu)∶n(Ce)=l∶1∶ 1,前驱体在300℃下焙烧2h,反应初始pH值为5时,该催化剂对甲基橙具有良好的催化性能,反应2h后甲基橙脱色率可达97.99%.且pH=5.0~9.0均可取得良好的降解效果,拓宽了pH适用范围.

  14. Atom probe study of the microstructural evolution induced by irradiation in Fe-Cu ferritic alloys and pressure vessel steels; Etude a la sonde atomique de l`evolution microstructurale sous irradiation d`alliages ferritiques Fe-Cu et d`aciers de cuve REP

    Pareige, P.

    1996-04-01

    Pressure vessel steels used in pressurized water reactors are low alloyed ferritic steels. They may be prone to hardening and embrittlement under neutron irradiation. The changes in mechanical properties are generally supposed to result from the formation of point defects, dislocation loops, voids and/or copper rich clusters. However, the real nature of the irradiation induced-damage in these steels has not been clearly identified yet. In order to improve our vision of this damage, we have characterized the microstructure of several steels and model alloys irradiated with electrons and neutrons. The study was performed with conventional and tomographic atom probes. The well known importance of the effects of copper upon pressure vessel steel embrittlement has led us to study Fe-Cu binary alloys. We have considered chemical aging as well as aging under electron and neutron irradiations. The resulting effects depend on whether electron or neutron irradiations ar used for thus. We carried out both kinds of irradiation concurrently so as to compare their effects. We have more particularly considered alloys with a low copper supersaturation representative of that met with the French vessel alloys (0.1% Cu). Then, we have examined steels used on French nuclear reactor pressure vessels. To characterize the microstructure of CHOOZ A steel and its evolution when exposed to neutrons, we have studied samples from the reactor surveillance program. The results achieved, especially the characterization of neutron-induced defects have been compared with those for another steel from the surveillance program of Dampierre 2. All the experiment results obtained on model and industrial steels have allowed us to consider an explanation of the way how the defects appear and grow, and to propose reasons for their influence upon steel embrittlement. (author). 3 appends.

  15. Determination Of 14 MeV Neutron Activation Cross-Section Of The Short Half-Life Element (Mg, Si, V, Fe, Cu, And Zr) By The Fast Neutron Activation Analysis

    Measurement of the (n, p), (n, α), and (n, 2n) reaction cross-sections of Mg, Si, V, Fe, Cu and Zr at the 14 MeV neutron energy have been done. The measurement of these reaction cross-sections were done by the fast neutron activation analysis method, where the samples were irradiated with 14 MeV neutron from the neutron generator. The gamma -rays emitted from the radioisotope produced by nuclear reaction were counted with the HPGe and the NaI (Tl) detectors. Based on the experimental which has been done the value of the reaction cross-sections of these materials above mentioned were same relatively regarding the literature with smaller error which range 1,82% up to 8,81%. About 63,6% of all cross-sections measured have the error smaller than 3%

  16. 土壤污染的修复方法研究--以表面活性剂强化微米Fe/Cu对有机氯农药的降解为例%The Remediation Method for Contaminated Soil:A Case Study of Degradation of Organochlorine Pesticides by Surfactant-Enhanced Fe/Cu Bimetallic System

    李川; 禹媛; 万金忠; 王新新; 卞师怡; 费菲; 薛建辉

    2015-01-01

    利用Cu作为催化金属与微米铁制成双金属体系处理主要污染物为六六六(HCH)和滴滴涕(DDT)的某污染场地土壤,探讨了不同表面活性剂(鼠李糖脂与Triton X-100(TX-100))对微米Fe/Cu双金属体系降解土壤中有机氯农药的影响。结果表明:相对于空白和只添加零价铁与微米Fe/Cu的三组的稳定,添加了两种表面活性剂的Fe/Cu双金属体系,35 d后土壤氧化还原电位(ORP)随时间呈缓慢上升趋势, Fe/Cu+TX-100至55 d时ORP由–400 mV升高到–300 mV;除Fe/Cu+鼠李糖脂组外,0~25 d内各组土壤pH随时间逐渐升高,从初始的5.0左右提高到6.5~7.2;微米Fe/Cu对污染物的降解效果相比零价铁有提高,鼠李糖脂与TX-100的投加能强化微米Fe/Cu对土壤中HCH和DDT的降解, TX-100的增强效果更为显著。当Fe投加量5%, Cu负载1%, TX-100浓度5 mmoL/L,初始pH 4.5时,处理55d后,α-HCH、γ-HCH、P, P’-DDD和P, P’-DDT的降解去除率达到100%、92.2%、95.7%和85.4%,总污染物去除率为90.0%。%The polluted soil with main pollutants as hexachlorocyclohexane (HCH) and dichloro-diphenyl-trichloroethane (DDT) was dechlorinated using the bimetallic system made of micron iron powder and Cu. And the effects of micron Fe/Cu with surface active agents (rhamnolipid and Triton X-100 (TX-100)) on dechlorination efficiency of polluted soil containing organic-chlorine pesticide were analyzed. The results showed that Oxidation-Reduction Potential(ORP)of polluted soil increased slowly with time 35 d after the addition of micron Fe/Cu, with both surface active agents comparing with micron Fe/Cu only and control experiment. ORP was raised from –400 mV to –300 mV 55 d after the addition of micron Fe/Cu with TX-100; pH increased with time during the first 25 d from 5.0 to 6.5~7.2 except for the addition of micron Fe/Cu with rhamnolipid; the bimetallic system made of micron Fe/Cu had more efficient dechlorination effect relative to zero

  17. Studies on formation and structures of ultrafine Cu precipitates in Fe-Cu model alloys for reactor pressure vessel steels using positron quantum dot confinement in the precipitates by their positron affinity. JAERI's nuclear research promotion program, H11-034 (Contract research)

    Hasegawa, Masayuki; Nagai, Yasuyoshi; Tang, Zheng; Yubuta, Kunio [Tohoku Univ., Sendai (Japan). Inst. for Materials Research; Suzuki, Masahide [Japan Atomic Energy Research Inst., Tokai, Ibaraki (Japan). Tokai Research Establishment

    2003-03-01

    Positron annihilation experiments on Fe-Cu model dilute alloys of nuclear reactor pressure vessel (RPV) steels have been performed after neutron irradiation in JMTR. Nanovoids whose inner surfaces were covered by Cu atoms were clearly observed. The nanovoids transformed to ultrafine Cu precipitates by dissociating their vacancies after annealing at around 400degC. The nanovoids and the ultrafine Cu precipitates are strongly suggested to be responsible for irradiation-induced embrittlement of RPV steels. Effects of Ni, Mn and P addition on the nanovoid and Cu precipitate formations were also studied. The nanovoid formation was enhanced by Ni and P, but suppressed by Mn. The Cu precipitates after annealing around 400degC were almost free from these doping elements and hence were pure Cu in the chemical composition. Furthermore the Fermi surface of the 'embedded' Cu precipitates with a body centered cubic crystal structure was obtained from two dimensional angular correlation of annihilation radiation (2D-ACAR) in a Fe-Cu single crystal and was agreed well with that from a band structure calculation. Theoretical calculation of positron confinement in Fe-Cu model alloys showed that a positron quantum dot state induced by positron affinity is attained for the embedded precipitates larger than 1 nm. A new position sensitive detector with a function of one dimensional angular correlation of annihilation radiation (1D-ACAR) has been developed that enables high resolution experiments over wide ranges of momentum distribution. (author)

  18. Studies on formation and structures of ultrafine Cu precipitates in Fe-Cu model alloys for reactor pressure vessel steels using positron quantum dot confinement in the precipitates by their positron affinity. JAERI's nuclear research promotion program, H11-034 (Contract research)

    Positron annihilation experiments on Fe-Cu model dilute alloys of nuclear reactor pressure vessel (RPV) steels have been performed after neutron irradiation in JMTR. Nanovoids whose inner surfaces were covered by Cu atoms were clearly observed. The nanovoids transformed to ultrafine Cu precipitates by dissociating their vacancies after annealing at around 400degC. The nanovoids and the ultrafine Cu precipitates are strongly suggested to be responsible for irradiation-induced embrittlement of RPV steels. Effects of Ni, Mn and P addition on the nanovoid and Cu precipitate formations were also studied. The nanovoid formation was enhanced by Ni and P, but suppressed by Mn. The Cu precipitates after annealing around 400degC were almost free from these doping elements and hence were pure Cu in the chemical composition. Furthermore the Fermi surface of the 'embedded' Cu precipitates with a body centered cubic crystal structure was obtained from two dimensional angular correlation of annihilation radiation (2D-ACAR) in a Fe-Cu single crystal and was agreed well with that from a band structure calculation. Theoretical calculation of positron confinement in Fe-Cu model alloys showed that a positron quantum dot state induced by positron affinity is attained for the embedded precipitates larger than 1 nm. A new position sensitive detector with a function of one dimensional angular correlation of annihilation radiation (1D-ACAR) has been developed that enables high resolution experiments over wide ranges of momentum distribution. (author)

  19. Carbonates-based noble metal-free lean NOx trap catalysts MOx-K2CO3/K2Ti8O17 (M = Ce, Fe, Cu, Co) with superior catalytic performance

    Zhang, Yuxia; You, Rui; Liu, Dongsheng; Liu, Cheng; Li, Xingang; Tian, Ye; Jiang, Zheng; Zhang, Shuo; Huang, Yuying; Zha, Yuqing; Meng, Ming

    2015-12-01

    A series of base metal-based lean NOx trap (LNT) catalysts MOx-K2CO3/K2Ti8O17 (M = Ce, Fe, Cu, Co) were synthesized by successive impregnations and employed for the storage and reduction of NOx in the emissions of lean-burn engines at 350 °C. The XRD and XANES/EXAFS results reveal that the active phases in the corresponding catalysts exist as CeO2, Fe2O3, CuO and Co3O4, respectively. Among all the catalysts, CoOx-K2CO3/K2Ti8O17 exhibits the best performance, which cannot only trap the NOx quickly and completely at lean condition, giving the highest storage capacity (3.32 mmol/g) reported so far, but also reduce the NOx at rich condition, showing a NOx reduction percentage as high as 99.0%. Meanwhile, this catalyst displays an ultralow NOx to N2O selectivity (0.3%) during NOx reduction. The excellent performance of CoOx-K2CO3/K2Ti8O17 results from its largest amount of surface active oxygen species as revealed by XPS, O2-TPD and NO-TPD. HRTEM, FT-IR and CO2-TPD results illustrate that several kinds of K species such as sbnd OK groups, K2O, surface carbonates and bulk or bulk-like carbonates coexist in the catalysts. Based upon the in situ DRIFTS results, the participation of K2CO3 in NOx storage is confirmed, and the predominant NOx storage species is revealed as bidentate nitrites formed via multiple kinetic pathways. The low cost and high catalytic performance of the CoOx-based LNT catalyst make it most promising for the substitution of noble metal-based LNT catalysts.

  20. Theoretical Study of Energetic Complexes (Ⅲ): Bis-(5-nitro-2Htetrazolato-N2)tetraammine Cobalt(Ⅲ) Perchlorate (BNCP) and Its Transition Metal (Ni/Fe/Cu/Zn) Perchlorate Analogues

    尚静; 张建国; 张同来; 黄辉胜; 张绍文; 舒远杰

    2012-01-01

    The geometric conformation and electronic structure of bis-(5-nitro-2H-tetrazolato-N2)tetraammine cobalt(Ⅲ) perchlorate and its Ni/Fe/Cu/Zn analogues are studied under the TPSS (Tao-Perdew-Staroverov-Scuseria) levels of density functional theory in order to throw light on the relationship between their energy gaps and impact sensitivity While the perchlorate ions are coordinated with the copper cation, which is different from the other four compounds NBO (Natural bond orbital) analyses indicated that the metal-ligand interaction in the Co complex is covalent, while the others are ionic. The analysis of the electrostatic potential demonstrated that the O atoms from the nitro-tetrazole ring and perchlorate were primarily negative, while the other atoms were positive. The study was also conducted to gain a better understanding of the correlation of the energy gap and impact sensitivity.

  1. Studies on formation and structures of ultrafine Cu precipitates in Fe-Cu model alloys for reactor pressure vessel steels using positron quantum dot confinement in the precipitates by their positron affinity. JAERI's nuclear research promotion program, H11-034 (Contract research)

    Hasegawa, M; Suzuki, M; Tang, Z; Yubuta, K

    2003-01-01

    Positron annihilation experiments on Fe-Cu model dilute alloys of nuclear reactor pressure vessel (RPV) steels have been performed after neutron irradiation in JMTR. Nanovoids whose inner surfaces were covered by Cu atoms were clearly observed. The nanovoids transformed to ultrafine Cu precipitates by dissociating their vacancies after annealing at around 400degC. The nanovoids and the ultrafine Cu precipitates are strongly suggested to be responsible for irradiation-induced embrittlement of RPV steels. Effects of Ni, Mn and P addition on the nanovoid and Cu precipitate formations were also studied. The nanovoid formation was enhanced by Ni and P, but suppressed by Mn. The Cu precipitates after annealing around 400degC were almost free from these doping elements and hence were pure Cu in the chemical composition. Furthermore the Fermi surface of the 'embedded' Cu precipitates with a body centered cubic crystal structure was obtained from two dimensional angular correlation of annihilation radiation (2D-ACAR) ...

  2. 电感耦合等离子体光谱法测定黄铁矿和黄铜矿中的铁铜硫%Determination of Fe, Cu and S in Pyrite and Chalcopyrite Samples by Inductively Coupled Plasma-Atomic Emission Spectrometry

    马新荣; 王蕾; 温宏利; 巩爱华

    2011-01-01

    The methods of water bath dissolution by aqua regia to open dissolution by acid mixing HC1-HNO3 -HF-HC104 and determine Fe, Cu and S in pyrite and chalcopyrite by Inductively Coupled Plasma-Atomic Emission Spectrometry ( ICP-AES ) are discussed in this paper. By applying a weighting method to prepare standard solutions, the error caused by scale reading can be greatly reduced during the dilution step. The advantages of using the water bath dissolution by aqua regia method include reduced digestion time, reduced amount of reagent addition and simple analytical processing. When Fe combines with Si in sulfide ore, it cannot be dissolved by aqua regia, yet it can when using open dissolution by acid mixing. The optimal spectrum lines were selected to determine high concentration of Fe, Cu and S ( x%-xx% ) with dilution factor of 1000. Both sample preparation methods are simple to operate and attain good accuracy and precision. The method was validated by the national standard materials of GBW 07267 ( pyrite ) and GBW 07268 ( chalcopyrite ). The accuracy ( RE ) and precision ( RSD, n =5 ) of Fe and Cu were less than 2%. However, accuracy and precision for S was lower when using the method of open dissolution by acid mixing, yielding a RE and RSD of -9.48% and - 18% , respectively. The short period stability of GBW 07267 and GBW 07268 was tested by 10 continuous determinations using the method of water bath dissolution with aqua regia; the RSD being less than 2.%样品用王水水浴和HCl-HNO3-HF-HClO4敞开酸溶两种溶矿方式分解,电感耦合等离子体发射光谱法(ICP-AES)测定黄铜矿和黄铁矿中铁、铜、硫.应用称重法配制标准溶液,明显地降低了在标准溶液在逐级稀释过程中由于体积读数等原因产生的误差.样品用王水水浴分解,消解时间短,试剂加入量少,分析步骤简单;由于硫化矿石中Fe的一部分可能与Si结合,王水无法将其全部溶解,对于Fe的测定采用混合酸敞开酸溶.

  3. 王水溶样-电感耦合等离子体发射光谱法同时测定铁铜铅锌硫化物矿石中8个元素%Simultaneous Determination of 8 Elemental Components of Fe, Cu, Zn and Pb in Sulfide Ores by ICP-AES with Aqua Regia Digestion

    温宏利; 马生凤; 马新荣; 王蕾; 范凡; 巩爱华

    2011-01-01

    建立了王水溶样-电感耦合等离子体发射光谱法同时测定铁、铜、铅、锌硫化物矿中Cu、Pb、Zn、As、Ag、Cd、Hg和Mo等8个元素的分析方法.确定了方法的溶矿及测定条件,用国家一级标准物质GBW07162(多金属贫矿石)和GBW07164(多金属矿石)进行精密度实验,除个别元素外,大多数的元素精密度(RSD,n=11)小于5%,准确度(RE)小于10%.通过一系列硫化物矿石标准物质进行方法验证,检测结果基本都在标准值的误差范围内,符合地质矿产开发的要求.方法简单,同时测定元素较多,线性范围宽,检出限低,尤其有利于硫化物矿石中的亲硫元素As、Ag、Hg的分析,实用性强.%A method is presented in this paper for examining sulphide ores, in order to determine Cu, Pb, Zn, As, Ag, Cd, Hg and Mo within Fe, Cu, Pb and Zn contained in the ores. This method utilizes Inductively Coupled Plasma-Atomic Emission Spectrometry ( ICP-AES) with aqua regia digestion. The technique for sample dissolution and measuring conditions is also presented. The accuracy and precision of the method were examined by analyzing reference materials GBW07162 (multi-metal lean ore) and GBW07164 (multi-metal ore). The test results indicate that the relative standard deviation ( RSD, n = 11) of most elemental components is less than 5% and the accuracy (RE) is less than 10% for most elements. The method was validated by different reference materials and the results were in good agreement with the certified values, thereby meeting the requirements of mineral exploitation. The method has the advantage of providing a simple, simultaneous determination of multiple elements, along with having a wide linearity range and low detection limit, especially for the determination of As, Ag and Hg.

  4. GMI in FeCuNbSiB/Cu multilayers

    Correa, M.A. [Departamento de Fisica, CCNE, UFSM, 97105-900, Santa Maria, RS (Brazil)]. E-mail: mmacorrea@gmail.com; Viegas, A.D.C. [Departamento de Fisica, CCNE, UFSM, 97105-900, Santa Maria, RS (Brazil); Silva, R.B. da [Departamento de Fisica, CCNE, UFSM, 97105-900, Santa Maria, RS (Brazil); Andrade, A.M.H. de [Departamento de Fisica, CCNE, UFSM, 97105-900, Santa Maria, RS (Brazil); Sommer, R.L. [Centro Brasileiro de Pesquisas Fisicas, 22290-180, Rio de Janeiro, RJ (Brazil)

    2006-10-01

    Very high magnetoimpedance (MI) measured at frequencies up to 1.8 GHz in single and multilayered thin films with composition Fe{sub 73.5}Cu{sub 1}Nb{sub 3}Si{sub 13.5}B{sub 9} and (Fe{sub 73.5}Cu{sub 1}Nb{sub 3}Si{sub 13.5}B{sub 9}+Cu) are reported. The magnetic properties of both systems are also compared. MI ratio as high as 300% for the multilayered samples were obtained.

  5. Induced anisotropy in nanocrystalline FeCuNbSiB

    The kinetics of induced anisotropy Kind was studied in nanocrystalline Fe73.5Cu1Nb3Si13.5B9, as well as in the amorphous precursor and in amorphous Fe78B13Si9. The nanocrystalline alloy was produced from the precursor by annealing at 813 K for 1 h and possessed an average FeSi grain size of 13 nm, as determined from x-ray diffraction. Annealing in a 0.2 T field at 723--773 K, above Tc of the amorphous phase, resulted in low values of Kind. The data were compared to the micromagnetic theory of Kronmueller to determine activation energy spectra. Kind for the nanocrystalline alloy is well described by this theory, however, with an activation energy spectrum that is much narrower than for the amorphous alloys. The limiting value of the anisotropy is K∞ ∼ 13 J/m3 consistent with that expected for the anisotropy in Fe-20at%.Si with the DO3 structure

  6. Determination of soil micronutrients (Fe, Cu, Mn, B) extracted by Mehlich 3 using MP-AES

    Krebstein, Kadri; Tõnutare, Tõnu; Rodima, Ako; Kõlli, Raimo; Künnapas, Allan; Rebane, Jaanus; Penu, Priit; Vennik, Kersti; Soobik, Liina

    2015-04-01

    The total concentration of micronutrients in soils is not a good predictor of its bioavailability and solubility. Therefore, during the decades several methods for the determination of plant availability and extractable fraction of micro- and macronutrients in soil were developed. Among several methods Mehlich 3 is the most appropriate due to its suitability for extracting soil micro- and macronutrients simultaneously. The AAS (atomic absorption spectroscopic) and ICP (inductively coupled plasma) methods are widely used for the analysis of microelements today. In 2011 the third method was added to this list with the appearance of the microwave plasma atomic emission spectrometer (MP-AES). This multielemental analytical equipment has a high potential in the soil analysis. Up to now there have been made some experiments for the use of MP-AES in soil and geological material analysis. But there is no information about the analysis of soil micronutrients extracted according to Mehlich 3 method and determined with the MP-AES. Due to the differences in atomization conditions the different emission and absorption lines are used in different instrumental methods. Therefore it is very important to choose the most suitable emission lines and the best atomization conditions. From the analytical viewpoint it is important to get coincidental results with other instrumental methods and from the agronomical point of view it is important to know the difference between AAS and ICP methods. For the experiment 51 soil samples were used. The samples were collected from A horizons of agricultural lands. The pH range was from 4.7 to 7.5 and organic matter content from 1.4 to 7.8%. The content of Mehlich 3 extractable micronutrients was determined using ICP and MP instrumental methods. The micronutrient contents ranged as follows: Fe - from 170 to 470 mg kg-1, Mn - from 5 to 190 mg kg-1, Cu - from 0.3 to 4.5 mg kg-1, B - from 0.2 to 2.1 mg kg-1. The optimal instrumental settings for iron, manganese, copper, and boron analysis according to Mehlich 3, using MP-AES method, are reported. Detection limits and limits of quantification for the analysed elements are calculated. Comparison of the analysed micronutrients content is provided by ICP and MP. Also the influence of soil pH and organic matter content on the results of analysis was reported.

  7. Highly Efficient Synthesis of Clean Biofuels from Biomass Using FeCuZnAIK Catalyst

    Song-bai Qiu; Yong Xu; Tong-qi Ye; Fei-yan Gong; Zhi Yang; Mitsuo Yamamoto; Yong Liu; Quan-xin Li

    2011-01-01

    Highly efficient synthesis of clean biofuels using the bio-syngas obtained from biomass gasification was performed over Fe1.5Cu1Zn1Al1K0.117 catalyst.The maximum biofuel yield from the bio-syngas reaches about 1.59 kg biofuels/(kgcatal·h) with a contribution of 0.57 kg alcohols/(kgcatal·h) and 1.02 kg liquid hydrocarbons/(kgcatal·h).The alcohol products in the resulting biofuels were dominated by the C2+ alcohols (mainly C2-C6 alcohols) with a content of 73.55%-89.98%.The selectivity of the liquid hydrocarbons (C5+) in the hydrocarbon products ranges from 60.37% to 70.94%.The synthesis biofuels also possess a higher heat value of 40.53-41.49 MJ/kg.The effects of the synthesis conditions,including temperature,pressure,and gas hourly space velocity,on the biofuel synthesis were investigated in detail.The catalyst features were characterized by inductively coupled plasma and atomic emission spectroscopy,X-ray diffraction,temperature programmed reduction,and the N2 adsorption-desorption isotherms measurements.The present biofuel synthesis with a higher biofuel yield and a higher selectivity of liquid hydrocarbons and C2+ alcohols may be a potentially useful route to produce clean biofuels and chemicals from biomass.

  8. Ion beam induced percolation clustering in Al-Fe-Cu films

    The concept of percolation can be applied to describe many phase transition problems and various disordered systems. An infinite percolation cluster at percolation threshold (Pc) is one of the most prominent fractal system. The fractal structure of the percolation clusters makes it possible to connect the universal exponents in percolation transition and the geometrical scaling quantities, like fractal dimensions Df. Increasing interest has recently been attractive to produce and study the ideal two-dimensional (2D) percolation films, which usually composed of a random mixture of crystalline and amorphous phases. In this paper, the authors report the direct observation of a percolation cluster consisting of two amorphous phases induced in thin solid films during crystalline-to-amorphous phase transformation by ion irradiation

  9. Magnetic properties of nanocrystalline FeCuNbSiB with huge creep induced anisotropy

    Herzer, Giselher; Budinsky, Viktoria; Polak, Christian, E-mail: gherzer@googlemail.com [Development Rapid Solidification Technology, Vacuumschmelze GmbH and Co. KG, D-63450 Hanau (Germany)

    2011-01-01

    Ribbons of originally amorphous Fe{sub 73.5}Cu{sub 1}Nb{sub 3}Si{sub 15.5}B{sub 7} have been annealed under tensile stress for about 4 seconds at temperatures between 450{sup 0}C and 750{sup 0}C. Under such short time conditions the optimum nanocrystalline state is achieved for annealing temperatures between 600{sup 0}C and 720{sup 0}C. This is about 100{sup 0}C higher than in more conventional heat treatments with annealing times in the order of an hour. The stress annealed ribbons reveal an almost perfectly linear hysteresis loop and a transverse domain pattern with zigzag domain walls characteristic for a magnetic easy plane perpendicular to the stress axis. The induced magnetic anisotropy increases proportional to the annealing stress and is comparable to that obtained after more prolonged annealing. We succeeded to induce anisotropy constants as high as K{sub u} {approx} 12 kJ/m{sup 3} which even exceed the local magneto-crystalline anisotropy (K{sub 1} {approx} 8 kJ/m{sup 3}) of the crystalline Fe-Si phase. Nonetheless, the coercivity is still as small as H{sub c} {approx} 8 A/m. This is to be compared to H{sub c} {approx} 0.5 A/m for field annealed samples where K{sub u} ({approx} 20 J/m{sup 3}) is smaller by more than two orders of magnitude. The behaviour of H{sub c} can be understood within the framework of the random anisotropy model.

  10. Study on Catalytic Wet Oxidation of H2S into Sulfur on Fe/Cu Catalyst

    2006-01-01

    A wet catalytic oxidation at room temperature was investigated with solution containing ferric, ferrous and cupric ions for H2S removal. The experiments were carried out in a two step process,and the results obtained show that the removal efficiency of H2S can always reach 100% in a 300 mm scrubbing column with four sieve plates, and the regeneration of ferric ions in 200 mm bubble column can match the consumed ferric species in absorption. Removal of H2S, production of elemental sulfur and regeneration of ferric, cupric ions can all be accomplished at the same time. No raw material is consumed except O2 in flue gas or air, the process has no secondary pollution and no problem of catalyst degradation and congestion.

  11. High-quality Ni-Fe/Cu multilayer films with antiferromagnetic coupling

    We report structural and magnetic properties of Ni83Fe17/Cu multilayer films with various buffer layer and sublayer thicknesses of copper dCu and Permalloy dPy deposited by face-to-face sputtering. The following features prove a good quality of our films: a wall-layered structure, complete antiferromagnetic coupling with a low coupling strength (2 x 10-5 J/m2 for dCu = 1 nm and 10-6 J/m2 for dCu = 2.1 nm) and a low coercive field with make them attractive for possible applications as giant magnetoresistance sensors. (author)

  12. Thermal Stability of CoFe/Cu/CoFe/IrMn Top Spin Valve

    ZHOU Guang-Hong; WANG Yin-Gang; QI Xian-Jin

    2009-01-01

    We present a study of thermal stability of the top spin valve with a structure of seed Ta (5nm)/Co75Fe25 (5nm)/Cu (2.5nm)/Co75Fe25n (5nm)/Ir20 Mn80 (12nm)/cap Ta (8nm) deposited at room temperature by magnetron sputtering. A vibrating sample magnetometer fixed with a heater was used to record the magnetic hysteresis loops at variational temperatures and x-ray diffraction was performed to characterize the structure of the multilayer.The exchange field Hex and the coercivity of the pinned CoFe layer Hcp decrease monotonically with increasing temperature.The coercivity of the free CoFe layer Hcf in the spin valve shows a maximum at 498K.The temperature dependences of Hex,Hcp and Hcf have also been discussed.

  13. Interfacial tension studies between Fe-Cu-Ni sulfide and halo-norilsk basalt slag system

    SU; Shangguo

    2005-01-01

    The interfacial tension of the matte/halo-Norilsk basalt slag systems of FeS-Cu2S-Ni3S2 and FeO-FeS were investigated using the sessile drop technique. The results indicate that interfacial tension decreases with increasing copper and nickel contents in the matte of FeS-Cu2S-Ni3S2 system while it increases with increasing oxygen content in the matte of FeO-FeS system. It is inferred from these results that two conditions are critical for the formation of giant Cu-Ni sulfide deposits. One is that mafic-ultramafic parent magma of sulfide deposits should be rich in copper and nickel where due to the low interfacial tension, it is difficult to form sulfide droplet in the early stage of magma evolution. In other words, sulfide liquid conglomeration occurs more difficultly. The other condition is that the magma emplacement should be shallow; and a lot of faults occur in the magma emplacement field. Since oxygen content is high in the environment, interfacial tension is high, which helps sulfide liquid conglomeration and consequently Cu-Ni sulfide deposits form.

  14. Specific heat and related thermophysical properties of liquid Fe-Cu-Mo alloy

    WANG HaiPeng; LUO BingChi; CHANG Jian; WEI BingBo

    2007-01-01

    The specific heat and related thermophysical properties of liquid Fe77.5Cu13Mo9.5 monotectic alloy were investigated by an electromagnetic levitation drop calorimeter over a wide temperature range from 1482 to 1818 K. A maximum undercooling of 221 K (0.13 Tm) was achieved and the specific heat was determined as 44.71 J·mol-1·K-1. The excess specific heat, enthalpy change, entropy change and Gibbs free energy difference of this alloy were calculated on the basis of experimental results. It was found that the calculated results by traditional estimating methods can only describe the solidification process under low undercooling conditions. Only the experimental results can reflect the reality under high undercooling conditions. Meanwhile, the thermal diffusivity, thermal conductivity, and sound speed were derived from the present experimental results. Furthermore, the solidified microstructural morphology was examined, which consists of (Fe) and (Cu) phases. The calculated interface energy was applied to exploring the correlation between competitive nucleation and solidification microstructure within monotectic alloy.

  15. Relation between Charpy impact properties and magnetism in thermally aged Fe-Cu model alloys

    This study demonstrates the possibility of applying magnetic methods to pressure vessel surveillance for irradiation embrittlement at nuclear power plants. Charpy impact test and magnetic hesteresis measurement were preformed on thermally aged Fe-1.0wt%Cu model alloys with and without pre-deformation. DBTT increased with increasing aging time. However, magnetic hysteresis parameters showed nonmonotonical changes. The phenomena are discussed in terms of Cu precipitation behavior and dislocation structure. (author)

  16. Coil-less fluxgate effect in CoNiFe/Cu wire electrodeposited under torsion

    Co19Ni49.6Fe31.4 layer was electrodeposited onto a twisted Cu wire and helical anisotropy was induced in the magnetic Co19Ni49.6Fe31.4 shell. The magnetic and coil-less fluxgate (CF) properties are presented. The Co19Ni49.6Fe31.4/Cu wire, produced at zero torsional strain, shows a CF output of nearly zero. The samples produced under torsional strains of 29.5π and 59π rad/m show a linear change in CF output in the low-frequency range. At higher frequencies the CF output shows two linear ranges. A maximum sensitivity of 150V/T is observed at 20 kHz driving-current frequency and 67 mA driving current for a wire produced under 59π rad/m torsional strain. It is also found that the slope of the CF curve depends on the direction of induced anisotropy. - Highlights: → Co19Ni49.6Fe31.4/Cu composite wire with helical anisotropy was produced by applying torsion to Cu wire during the electrodeposition process. → Sensitivity of coil-less fluxgate sensor increases with increasing torsion. → The slope of the coil-less fluxgate curve depends on the direction of induced anisotropy.

  17. Pressure stress-impedance effect in FeCuNbSiB amorphours ribbons

    2009-01-01

    The stress-impedance effect in Fe73.5Cu1Nb3Si13.5B9 (at%) ribbons is measured to investigate the influences of vacuum annealing and pressure stress. The results can be explained by the influence of induced anisotropy in the magnetization processes at the chosen drive current frequency of 90 MHz. The maximum SI% value of the ribbon annealed at 300 ℃ is 2.52%.

  18. The microstructure of liquid immiscible Fe-Cu-based in situ formed amorphous/crystalline composite

    In the microstructures of slowly and rapidly cooled liquid of the immiscible alloy Fe30Cu32Ni10Si13Sn4B9Y2 two distinct regions were observed following arc melting and slow cooling, confirming that liquid/liquid phase separation had occurred. Rapid cooling from a temperature within the liquid immiscibility gap, melt spinning, resulted in an amorphous/crystalline composite, formed from the previously melted Fe- and Cu-rich regions, respectively. Transmission electron microscopic studies of this melt-spun ribbon revealed the glassy nature of the Fe-rich matrix, as well as of the Fe-rich spheres formed within the previously existing Cu-rich liquid

  19. Distribution of Ca, Fe, Cu and Zn in primary colorectal cancer and secondary colorectal liver metastases

    Al-Ebraheem, A. [Department of Radiography, City Community and Health Sciences, City University, London, EC1V 0HB (United Kingdom); Mersov, A. [Department of Medical Physics and Applied Radiation Sciences, McMaster University, 1280 Main St. West. Hamilton, Ontario, L8S 4L8 (Canada); Gurusamy, K. [HPB and Liver Transplant Surgery, Royal Free and University College School of Medicine, UCL and Royal Free NHS trust, London (United Kingdom); Farquharson, M.J., E-mail: farquhm@mcmaster.c [Department of Medical Physics and Applied Radiation Sciences, McMaster University, 1280 Main St. West. Hamilton, Ontario, L8S 4L8 (Canada)

    2010-07-21

    A microbeam synchrotron X-ray fluorescence ({mu}SRXRF) technique has been used to determine the localization and the relative concentrations of Zn, Cu, Fe and Ca in primary colorectal cancer and secondary colorectal liver metastases. 24 colon and 23 liver samples were examined, all of which were formalin fixed tissues arranged as microarrays of 1.0 mm diameter and 10 {mu}m thickness. The distribution of these metals was compared with light transmission images of adjacent sections that were H and E stained to reveal the location of the cancer cells. Histological details were provided for each sample which enable concentrations of all elements in different tissue types to be compared. In the case of liver, significant differences have been found for all elements when comparing tumour, normal, necrotic, fibrotic, and blood vessel tissues (Kruskal Wallis Test, P<0.0001). The concentrations of all elements have also been found to be significantly different among tumour, necrotic, fibrotic, and mucin tissues in the colon samples (Kruskal Wallis Test, P<0.0001). The concentrations of all elements have been compared between primary colorectal samples and colorectal liver metastases. Concentration of Zn, Cu, Fe and Ca are higher in all types of liver tissues compared to those in the colon tissues. Comparing liver tumour and colon tumour samples, significant differences have been found for all elements (Mann Whitney, P<0.0001). For necrotic tissues, significant increase has been found for Zn, Ca, Cu and Fe (Mann Whitney, P<0.0001 for Fe and Zn, 0.014 for Ca, and 0.001 for Cu). The liver fibrotic levels of Zn, Ca, Cu and Fe were higher than the fibrotic colon areas (independent T test, P=0.007 for Zn and Mann Whitney test P<0.0001 for Cu, Fe and Ca). For the blood vessel tissue, the analysis revealed that the difference was only significant for Fe (P=0.009) from independent T test.

  20. Specific heat and related thermophysical properties of liquid Fe-Cu-Mo alloy

    2007-01-01

    The specific heat and related thermophysical properties of liquid Fe77.5Cu13Mo9.5 monotectic alloy were investigated by an electromagnetic levitation drop calo-rimeter over a wide temperature range from 1482 to 1818 K.A maximum under-cooling of 221 K(0.13 Tm)was achieved and the specific heat was determined as 44.71 J·mol1·K1.The excess specific heat,enthalpy change,entropy change and Gibbs free energy difference of this alloy were calculated on the basis of experimental results.It was found that the calculated results by traditional esti-mating methods can only describe the solidification process under low under-cooling conditions.Only the experimental results can reflect the reality under high undercooling conditions.Meanwhile,the thermal diffusivity,thermal conductivity,and sound speed were derived from the present experimental results.Furthermore,the solidified microstructural morphology was examined,which consists of(Fe)and(Cu)phases.The calculated interface energy was applied to exploring the correlation between competitive nucleation and solidification microstructure within monotectic alloy.

  1. FMR Investigation of the nanocrystalline FeCuNbSiB glass-covered wires

    The evolution of magnetic anisotropy and magnetization mechanisms during nanocrystalline phase formation and crystallization of Fe73.5Cu1Nb3Si13.5B9 glass-covered wires are studied by ferromagnetic resonance. The modifications of the magnetic anisotropy due to structural changes are determined from the main resonance peaks. Changes in the magnetization processes are revealed by the low field peaks detected for all samples

  2. The structure and magnetic properties of a powder FeCuNbSiB material

    We investigated the influence of milling on the structure and magnetic properties of Fe73.5Cu1Nb3Si13.5B9 alloy as a function of milling time. We found that with an increase of milling time the size of the powder decreases and both the coercivity and the volume fraction of the crystalline phase increase

  3. Permeability spectra of neutron-irradiated and annealed amorphous FeCuNbSiB ribbons

    The neutron irradiation effects of soft magnetic properties in the as-quenched and the annealed amorphous Fe73.5Cu1Nb3Si13.5B9 alloys were studied by complex permeability spectra measurement. The annealing at 823 K caused the decrease of permeability from irreversible domain wall motion but increase the permeability from reversible magnetization, compared to the as-quenched sample. The neutron irradiation in the as-quenched sample increases the permeability from both irreversible and reversible magnetization processes. The neutron irradiation in the annealed sample showed the increase of permeability from irreversible domain wall motion, but decrease of permeability from reversible magnetization

  4. Structure and magnetic behaviour of Fe-Cu-Nb-Si-B-Al alloys

    Fe was substituted by Al up to 7 at% in Finemet. After annealing at 550 deg. C all samples were nanocrystalline, with more or less ordered α-Fe(Si,Al) grains; the DO3-like ordering was the most dominant in samples with 5 and 7 at% of Al. In as-quenched state Al decreased linearly the magnetization, but up to 3 at% enhanced the Curie temperature of the alloy. The Curie temperature of the crystalline phase and the magnetization in annealed samples abruptly decreased, when there was more than 5 at% of Al in the alloy

  5. Structural evolution and the kinetics of Cu clustering in the amorphous phase of Fe-Cu-Nb-Si-B alloy

    Gupta, P.; Gupta, A.; Shukla, A.; Ganguli, Tapas; Sinha, A. K.; Principi, G.; Maddalena, A.

    2011-08-01

    An attempt has been made to investigate the evolution of the structure of the amorphous phase of Fe73.9 Cu0.9 Nb3.1 Si13.2 B8.9 (finemet) alloy by a combination of wide-angle x-ray scattering, small angle x-ray scattering (SAXS), Mössbauer spectroscopy and X-ray absorption near edge spectroscopy on the supposition that they would provide complementary information. Before the onset of nanocrystallization, the amorphous phase undergoes a structural relaxation resulting in small increase in the hyperfine field and a decrease in the width of the first diffraction maxima. There is an increase in the topological ordering in the system, though chemical inhomogeneity sets-in due to the clustering of Cu atoms in the pure amorphous state of this alloy. Annealing at 400 °C (well below the crystallization temperature) for different time durations results in occurrence of Cu clusters having fcc structure. Kinetics of Cu clustering is studied using SAXS. The incubation time for the clustering at 400 °C is ˜120 min. With further annealing, the average cluster size gradually increases from the initial value of ˜0.4 nm, reaching a value of ˜0.6 nm after annealing for 720 min. Cluster size exhibits a t1/2 dependence, suggesting a diffusion controlled growth.

  6. Heterogeneous UV/Fenton catalytic degradation of wastewater containing phenol with Fe-Cu-Mn-Y catalyst

    郑展望; 雷乐成; 徐生娟; 岑沛霖

    2004-01-01

    The heterogeneous UV/Fenton process with the appropriate amount of Fe-Mn-Cu-Y as catalyst was developed and various operation conditions for the degradation of phenol were evaluated. The results indicated that by using the heterogeneous UV/Fenton process, the CODcr removal rate reached almost 100% for wastewater containing phenol. Compared with the homogeneous process, the developed catalyst could be used at wider pH range in the UV/Fenton process. Comparison of various heterogeneous process showed that heterogeneous UV/Fenton process was best. The heterogeneous UV/Fenton process with Fe-Mn-Cu-Y catalyst is highly efficient in degrading various organic pollutants.

  7. EXAFS study on solute precipitation in FeCu alloy induced by energetic electron bombardments and thermal aging

    The extended X-ray absorption fine structure (EXAFS) measurement is a useful tool for the observation of local atomic arrangements around selected atoms. We performed EXAFS measurements for the electron-irradiated and the thermally-aged Fe–0.6 wt.% Cu alloy and compared the experimental result with that of the simulation by the FEFF simulation code in order to investigate the local atomic structure around Cu atoms. Cu precipitates which were produced by the thermal aging at 773 K transformed from the bcc structure to the fcc structure as the precipitates grow large enough. However, for electron-irradiated specimens, although the hardness greatly increased, the transformation of Cu precipitates from the bcc to the fcc structure was not clearly confirmed. This result indicates that small sized Cu precipitates which had the bcc structure were produced by the electron irradiation and they could hardly coarsen during the irradiation

  8. Magnetic properties of FeCuNbSiB nanocrystallized by flash annealing under high tensile stress

    Herzer, Giselher; Budinsky, Viktoria; Polak, Christian [Vacuumschmelze GmbH and Co KG, Gruener Weg 37, 63450 Hanau (Germany)

    2011-10-15

    We have investigated the creep induced anisotropy, magnetostriction, domain structure and coercivity of nanocrystalline Fe{sub 73.5}Cu{sub 1}Nb{sub 3}Si{sub 15.5}B{sub 7} crystallized by flash annealing under high tensile stress up to 800 MPa. The samples reveal a magnetic easy plane perpendicular to the stress axis with anisotropy constants up to K{sub u} {approx} 12 kJ/m{sup 3} which even exceed the local magneto-crystalline anisotropy (K{sub 1} {approx} 8 kJ/m{sup 3}) of the crystalline Fe-Si phase. Although coercivity increases with K{sub u}, it remains reasonably small even for huge induced anisotropy constants. The coercivity mechanism can be understood from the interplay of the induced anisotropy and the random fluctuations of the local magneto-crystalline anisotropy of the crystallites. The tensile stress applied during annealing also affects the saturation magnetostriction constant {lambda}{sub s}. Thus, {lambda}{sub s} decreases with increasing magnitude of the annealing stress. This behaviour is compared to the elastic stress dependence of magnetostriction. The latter is well-known for amorphous Co-base alloys, but can also be observed in nanocrystalline alloys. The experimental results will be discussed theoretically in terms of the strain dependence of the magnetic anisotropy energy which ultimately provides the physical origin of magnetostrictive phenomena. (Copyright copyright 2011 WILEY-VCH Verlag GmbH and Co. KGaA, Weinheim)

  9. First order reversal curve investigation of the hard and soft magnetic phases of annealed CoFeCu nanowire arrays

    (CoFe)1−xCux (x=0.12–0.84) nanowire arrays were ac-pulse electrodeposited into anodic aluminum oxide templates. The electrodeposition was performed in a constant electrolyte while Cu content was controlled by off-time between pulses. Nanowires with 30 nm diameter and the certain lengths with the both bcc-CoFe and fcc-Cu phases were obtained. Magnetization and coercivity of the nanowires decreased with increasing the Cu content. Annealing improved the coercivity and a remarkable increase in magnetization of nanowires with high Cu contents was observed. A two-phase treatment was seen for annealed samples with high Cu contents. First order reversal curves showed a hard magnetic phase with almost constant magnetic properties and coercivity of ∼2500 Oe. The results showed that main source of the various magnetic behaviors of the samples may be attributed to increase in soft magnetic phase. A single domain treatment with a narrow interacting field and coercive field distributions was also observed for the annealed samples with high Cu content

  10. Development of a depth-resolved x-ray magnetic circular dichroism: application to Fe/Cu(100) ultrathin films

    A depth-resolved technique is applied in the x-ray magnetic circular dichroism (XMCD) method by controlling the probing depth of the electron yield XMCD spectra. The usefulness of this technique is demonstrated for the study of magnetic structures of 4 and 8 ML Fe films grown on Cu(100), which are known to exhibit peculiar magnetic depth profiles. It was directly shown that the 4 ML film is uniformly magnetized, while the magnetic moment is localized at the surface in the case of the 8 ML film. The XMCD spectrum for each layer of the 4 ML film was separately extracted. All the extracted spectra were almost identical to each other, confirming the ferromagnetic coupling over the whole film. As for the 8 ML film, it was suggested that the surface two layers are ferromagnetically coupled, while the inner layers are in a spin density wave state with a wavenumber q=2π/2.4d

  11. Stabilities of thiomolybdate complexes of iron; implications for retention of essential trace elements (Fe, Cu, Mo) in sulfidic waters.

    Helz, George R; Erickson, Britt E; Vorlicek, Trent P

    2014-06-01

    In aquatic ecosystems, availabilities of Fe, Mo and Cu potentially limit rates of critical biological processes, including nitrogen fixation, nitrate assimilation and N2O decomposition. During long periods in Earth's history when large parts of the ocean were sulfidic, what prevented these elements' quantitative loss from marine habitats as insoluble sulfide phases? They must have been retained by formation of soluble complexes. Identities of the key ligands are poorly known but probably include thioanions. Here, the first determinations of stability constants for Fe(2+)-[MoS4](2-) complexes in aqueous solution are reported based on measurements of pyrrhotite (hexagonal FeS) solubility under mildly alkaline conditions. Two linear complexes, [FeO(OH)MoS4](3-) and [(Fe2S2)(MoS4)2](4-), best explain the observed solubility variations. Complexes that would be consistent with cuboid cluster structures were less successful, implying that such clusters probably are minor or absent in aqueous solution under the conditions studied. The new data, together with prior data on stabilities of Cu(+)-[MoS4](2-) complexes, are used to explore computationally how competition of Fe(2+) and Cu(+) for [MoS4](2-), as well as competition of [MoS4](2-) and HS(-) for both metals would be resolved in solutions representative of sulfidic natural waters. Thiomolybdate complexes will be most important at sulfide concentrations near the [MoO4](2-)-[MoS4](2-) equivalence point. At lower sulfide concentrations, thiomolybdates are insufficiently stable to be competitive ligands in natural waters and at higher sulfide concentrations HS(-) ligands out-compete thiomolybdates. PMID:24226648

  12. Local X-ray magnetic circular dichroism study of Fe/Cu(111) using a tunneling smart tip.

    DiLullo, Andrew; Shirato, Nozomi; Cummings, Marvin; Kersell, Heath; Chang, Hao; Rosenmann, Daniel; Miller, Dean; Freeland, John W; Hla, Saw Wai; Rose, Volker

    2016-03-01

    Localized spectroscopy with simultaneous topographic, elemental and magnetic information is presented. A synchrotron X-ray scanning tunneling microscope has been employed for the local study of the X-ray magnetic circular dichroism at the Fe L2,3-edges of a thin iron film grown on Cu(111). Polarization-dependent X-ray absorption spectra have been obtained through a tunneling smart tip that serves as a photoelectron detector. In contrast to conventional spin-polarized scanning tunneling microscopy, X-ray excitations provide magnetic contrast even with a non-magnetic tip. Intensity variations in the photoexcited tip current point to chemical variations within a single magnetic Fe domain. PMID:26917146

  13. Experimental and theoretical study of the magnetic properties and XMCD spectra of Ru clusters deposited on Fe/Cu(001)

    Minar, J.; Bornemann, S.; Mankovsky, S.; Ebert, H. [Department Chemie und Biochemie, Lehrbereich Physikalische Chemie, Ludwig-Maximilians-Universitaet Muenchen, Butenandtstr 5-13, 81377 Muenchen (Germany); Martins, M.; Reif, M.; Glaser, L.; Wurth, W. [Institut fuer Experimentalphysik, Universitaet Hamburg, Luruper Chaussee 149, 22761 Hamburg (Germany)

    2010-05-15

    We present results of an experimental study of magnetic properties of small Ru clusters deposited on a thin Fe film grown on Cu(001) surface. X-ray magnetic circular dichroism (XMCD) measurements show finite spin and orbital moments of Ru dimers and trimers, however a magnetic moment for a Ru monomer has been not observed. A corresponding theoretical study based on the fully relativistic multiple scattering KKR method is presented. Detailed theoretical analysis has been performed to explain the experimental findings. In particular a direct comparison of the calculated XMCD with the experiments suggests diffusion into the surface as a possible reason for the apparent quenching of the spin magnetic moment for Ru monomers. (Abstract Copyright [2010], Wiley Periodicals, Inc.)

  14. Atomic computer simulation of the formation and growth process of Cu-precipitate in Fe-Cu alloy

    Fukuta, T.; Ozaki, K. [Faculty of Computer Science and Systems Engineering, Okayama Prefectural Univ. (Japan); Akahoshi, Y.; Harada, S. [Faculty of Engineering, Kyushu Inst. of Tech. (Japan)

    2007-07-01

    We focus on nanoscale copper-rich precipitates and try to clarify the effect of the nanoscale copper-rich precipitates on embrittlement of reactor pressure vessel steels. Our final goal is to evaluate such embrittlement from microscopic viewpoint based on atomistic simulation. In this study, we propose Multi Vacancy Lattice Monte Carlo (MVLMC) method which can analyze the model that has more than one vacancy. We showed that process of copper clustering consists of the two phases, i.e., formation phase, and combination phase. And, we analyzed a combination process of a cluster using MVLMC in detail, and evaluate formation of a cluster using distance between clusters. It is noted that in combination between a nano cluster smaller than 1 nm and a cluster of about 2 nm, minute nano clusters separate from the former cluster and are absorbed by the latter cluster. Moreover, we found that a nano cluster is formed by distance of about 1.5 nm extent from other clusters in a formation process of a cluster and that distance between clusters of about 2 nm is about 10 nm. (orig.)

  15. Atomic computer simulation of the formation and growth process of Cu-precipitate in Fe-Cu alloy

    We focus on nanoscale copper-rich precipitates and try to clarify the effect of the nanoscale copper-rich precipitates on embrittlement of reactor pressure vessel steels. Our final goal is to evaluate such embrittlement from microscopic viewpoint based on atomistic simulation. In this study, we propose Multi Vacancy Lattice Monte Carlo (MVLMC) method which can analyze the model that has more than one vacancy. We showed that process of copper clustering consists of the two phases, i.e., formation phase, and combination phase. And, we analyzed a combination process of a cluster using MVLMC in detail, and evaluate formation of a cluster using distance between clusters. It is noted that in combination between a nano cluster smaller than 1 nm and a cluster of about 2 nm, minute nano clusters separate from the former cluster and are absorbed by the latter cluster. Moreover, we found that a nano cluster is formed by distance of about 1.5 nm extent from other clusters in a formation process of a cluster and that distance between clusters of about 2 nm is about 10 nm. (orig.)

  16. Microstructure and mechanical properties of spray-deposited Al-Si-Fe-Cu-Mg alloy containing Mn

    2003-01-01

    Al-20Si-5Fe-3Cu-lMg alloy was synthesized by the spray atomization and deposition technique. The microstructure and mechanical properties of the spray deposited hypereutectic Al-Si alloy were studied using optical microscopy, scanning electron microscopy, X-ray diffraction, TEM (Transmission Electron Microscope) and HREM (High-resolution Electron Microscope), DSC (Differential Scanning Calorimetry), microhardness measurement, and tensile tests. The effects of Mn on the microstructural evolution of the highsilicon aluminum alloy after extrusion and heat treatment have been examined. The results show that two kinds of phases, i.e. S (Al2CuMg) and σ(Al5Cu6Mg2), precipitated from matrix and improved the tensile strength of the alloy efficiently at both the ambient and elevated temperatures (300℃). The tensile test results indicate that the spray-deposited Al-20Si-SFe-3Cu-1Mg alloy has better strength than the powder metallurgy processed Al-20Si-3Cu-1Mg alloy at elevated temperature.

  17. A GREENER SYNTHESIS OF CORE (FE, CU)-SHELL (AU, PT, PD AND AG) NANOCRYSTALS USING AQUEOUS VITAMIN C

    A greener method to fabricate the novel core (Fe and Cu)-shell (noble metals) metal nanocrystals using aqueous ascorbic acid (vitamin C) is described. Transition metal salts such as Cu and Fe were reduced using ascorbic acid, a benign naturally available antioxidant, and then add...

  18. High frequency behaviours and Mössbauer study of field annealed FeCuNbSiB alloy ribbons

    This paper investigates the high frequency behaviours and magnetic anisotropy of rapidly solidified FINEMET (Fe73.5Si13.5B9Nb3Cu1) alloy ribbons annealed in an applied magnetic field. It finds that the ribbons annealed with the applied magnetic field show much higher resonance frequencies and have even higher permeability at higher frequencies than the samples annealed without the magnetic field and the non-annealed ribbons. Mössbauer spectroscopy had been employed to study the spatial distribution of the magnetic moments of five selected FINEMET alloy ribbons in different heat-treated conditions. The results show that an easy plane has been established after annealling in the magnetic field, while for the other ribbons this effect is not significant. Hence, the relationship between magnetic field annealing and high frequency property has been bridged by the bianisotropic theory. (condensed matter: electronic structure, electrical, magnetic, and optical properties)

  19. Structural relaxation and crystallization in the Fe-Cr-Si-B and Fe-Cu-Cr-Si-B amorphous alloys

    Structural relaxation, crystallization and optimisation processes in soft magnetic amorphous alloys based on iron are examined by applying different experimental techniques: X-ray diffraction analysis, high-resolution electron microscopy, measurements of magnetic and electric properties (permeability, after-effect resistivity). The presented results are discussed in terms of annealing out of microvoids, formation of nanocrystalline phase and changes of effective magnetostriction constant. (author)

  20. Microstructural study of nanocrystalline Fe-(Cu-Nb)-Si-B ribbons obtained by a nitriding thermochemical treatment

    The crystallization process of amorphous Fe74Si14B12, Fe73.5Cu1Si13.5B12, Fe74Nb3Si14B9 and Fe73.5Cu1Nb3Si13.5B9 ribbons was investigated by annealing the ribbons under vacuum at 520 deg. C for 6 h. Only Nb containing samples show a nanocrystalline state consisting of α-Fe(Si) nanograins embedded in a remaining amorphous phase. The amorphous ribbons were then submitted to a nitriding thermochemical treatment at 520 deg. C for 6 and 18 h under ammonia. It is observed that crystallization occurs prior to nitrogenation. Upon nitrogenation, a reactive diffusion process of nitrogen is observed, which appears to be slower in the partially crystallized ribbons, due to the presence of a remaining amorphous phase. In the crystalline regions, the α-Fe(Si) phase is disproportionated into α-Fe and probably Si-N precipitates. Then Fe4N is formed when nitrogenation proceeds further

  1. On the concentration and separation of the trace-elements fe, cu, zn, mn, pb, mo and co : Paper chromatography

    Erkelens, P.C. van

    1961-01-01

    Paper chromatographic separations are described by which the minor constituents of biological ashes are separated either into: (Pb) - Mn - Co - (Pb) - Cu - Fe, Mo, Zn; or into: Cu, Mn, Co - Pb - Fe - Mo - Zn.

  2. Thermal stability of the induced magnetic anisotropy and structure of the nanocrystalline alloy FeCuNbSiB

    The magnetic anisotropy induced in the ribbons of the Fe73.5Cu1Nb3Si13.5B9 alloy in the course of stress annealing combined with the nanocrystallising one was investigated. Crystalline phases formed during the above treatments were studied by the Moessbauer method. Analysis of the Moessbauer results showed that the content of the Fe-Si phases depends neither on the exposure time nor on the value of the induced magnetic anisotropy constant. At the same time, in the regions containing, along with Fe, Nb and B the process of redistributing the elements proceeds with time, and the deeper the process, the higher the thermal stability of the induced magnetic anisotropy

  3. Carbon-Coated Core-Shell Fe-Cu Nanoparticles as Highly Active and Durable Electrocatalysts for a Zn-Air Battery.

    Nam, Gyutae; Park, Joohyuk; Choi, Min; Oh, Pilgun; Park, Suhyeon; Kim, Min Gyu; Park, Noejung; Cho, Jaephil; Lee, Jang-Soo

    2015-06-23

    Understanding the interaction between a catalyst and oxygen has been a key step in designing better electrocatalysts for the oxygen reduction reaction (ORR) as well as applying them in metal-air batteries and fuel cells. Alloying has been studied to finely tune the catalysts' electronic structures to afford proper binding affinities for oxygen. Herein, we synthesized a noble-metal-free and nanosized transition metal CuFe alloy encapsulated with a graphitic carbon shell as a highly efficient and durable electrocatalyst for the ORR in alkaline solution. Theoretical models and experimental results demonstrated that the CuFe alloy has a more moderate binding strength for oxygen molecules as well as the final product, OH(-), thus facilitating the oxygen reduction process. Furthermore, the nitrogen-doped graphitic carbon-coated layer, formed catalytically under the influence of iron, affords enhanced charge transfer during the oxygen reduction process and superior durability. These benefits were successfully confirmed by realizing the catalyst application in a mechanically rechargeable Zn-air battery. PMID:25967866

  4. Comment on “Planar Hall resistance ring sensor based on NiFe/Cu/IrMn trilayer structure” [J. Appl. Phys. 113, 063903 (2013)

    Østerberg, Frederik Westergaard; Henriksen, Anders Dahl; Rizzi, Giovanni;

    2013-01-01

    In a recent paper, Sinha et al. compared sensitivities of planar Hall effect sensors with different geometries that are all based on the anisotropic magnetoresistance of permalloy. They write that the sensitivity of a planar Hall effect sensor with a ring geometry is a factor of √2 larger than the...... sensitivity of the so-called planar Hall effect bridge (PHEB) sensor of equal size. Osterberg et al do not agree on the signal calculation for a ring sensor derived by Sinha et al. and claim that this adversely affects the results....

  5. The application of photoelectron spectroscopy in the study of corrosion and oxidation mechanisms of alloys: Inconel 182, Fe/Cu(100 and U-Zr-Nb

    In. this work a study of the oxidation/corrosion process of three systems of metallic materials by Photoemission Spectroscopy is presented. In the first system, it was investigated the corrosion of Ineonel 182 at simulated Pressurized Water Reactor (PWR) environment. Samples with and without surface chemical treatment were exposed to the simulated environment for until 18 weeks. The oxide layer formed on the surfaces of the samples at different conditions was characterized by Scanning Electron Microscopy and XPS coupled with argon ion sputtering. The comparison between the oxide films grown on the samples showed that the oxide layer formed on the chemically treated sample is thinner and relatively Cr-rich. In second system it was studied the initial oxidation at room temperature of epitaxial films of Fe evapored on Cu (100). The films were deposited with two different thicknesses in order to get tbe fcc Fe (100) and bcc Fe (110) surfaces. The results, obtained by photoemission spectroscopy at the TEMPO beamline of the Synchrotron Soleil, showed the formation of distinct oxides films. The surfaces also presented different kinetics of oxidation and the (110) Fe-bcc showed highest reactivity. The analysis of the data indicated the Fe1-xO formation on fcc Fe (100) and suggested the Fe1-xO and FC304 formation on (110) Fe-bcc surface. In the last system, it was investigated the initial oxidation of U-Zr-Nb alloys at room temperature. For this experiment, the alloys were exposed to oxygen in ultra high vacuum. The analysis of the U 4f peak showed the fast formation of U)2 on the surfaces and similar kinetics of oxidation between the U and the U-Zr-Nb alloy. The alloying elements showed slower oxidation. The Zr 3d peak suggested the zr02 formation while the Nb 3d peak showed a remarkable enlargement that became necessary a deconvolution which indicated the formation ofNhO, Nb02 and N205. (author)

  6. Pressure-temperature-fluid evolution in parts of SPSZ-implication for boron metasomatism and U-Fe-Cu-P mineralization

    The objectives of this project is to establish the relationships among the different tourmaline-and apatite- rocks and the enclosing lithologies, particularly with the uranium mineralization. Mineralogical variation of the rocks close to these deposits will be mapped in detail. Special importance will be given to establish the mutual relations among tourmaline, apatite, magnetite and the U-Th ores

  7. Microstructural evolution and the magnetic properties of melt-spun Sm-Co-Cu-B and Sm-Co-Fe-Cu-B ribbons

    An attempt has been made to obtain nanocomposite from Sm-Co-Cu-based alloys. Sm12Co60Cu26B2 and Sm16.7Co48.3Fe25Cu8.3B1.7 alloys were selected by considering the two-phase region of the Sm-Co-Cu ternary phase diagram and the phase equilibria of Sm-Co-Fe. Sm12Co60Cu26B2 melt-spun ribbon transformed from TbCu7 (1:7 H) type to Th2Ni17 (2:17 H)-type phase on annealing at 600 deg. C for 10 min and exhibited coercivity (iHc) of ∼8.0 kOe. Co23B6 precipitates were found either within the grains or at the grain boundary of the hard magnetic phase, and recoil curves in the demagnetization curve indicated exchange coupling between the two phases. Sm16.7Co48.3Fe25Cu8.3B1.7 melt-spun ribbon showed an intermediate value of coercivity (iHc∼3-5 kOe). (FeCo)-B precipitates were found at the grain boundaries of SmCo5 hard magnetic phase

  8. Geochemistry and Re-Os geochronology of the organic-rich sedimentary rocks in the Jingtieshan Fe-Cu deposit, North Qilian Mountains, NW China

    Yang, Xiuqing; Zhang, Zuoheng; Li, Chao; Duan, Shigang; Jiang, Zongsheng

    2016-04-01

    The Jingtieshan Group in the North Qilian Mountains, NW China, is dominantly composed of banded iron formations (BIFs), copper deposits and organic-rich sedimentary rocks (ORS, carbonaceous phyllite). X-ray diffraction analysis of the ORS shows the mineral assemblage to be quartz + clay minerals. The total organic carbon contents show a range of 0.44-1.72%. Here we present the results of the geochemistry and Re-Os geochronology of the ORS from the Jingtieshan Group. The high values of Chemical Index of Alteration (CIA), Chemical Index of Weathering (CIW), Plagioclase Index of Alteration (PIA), and Th/U ratio, indicate intense weathering. The Al2O3/TiO2, Zr/Sc, Th/Sc, La/Th ratios, high rare earth elements abundances, light rare earth elements enrichment (normalized to chondrite), and distinctly negative Eu anomalies, suggest that the Jingtieshan Group ORS were derived mainly from felsic volcanic units. The new Re-Os isochron age of 1308 ± 100 Ma (2σ, n = 6, MSWD = 23) broadly overlap with the previous published ages determined using Sm-Nd and U-Pb isotope systems. The new age represents the depositional age of the Jingtieshan Group, as well that of BIF in the Jingtieshan area. Furthermore, the initial 187Os/188Os ratios (0.44 ± 0.07) indicate that the Os in the seawater was dominantly derived from hydrothermal fluids (∼75%). The Ce anomaly (Ce/Ce∗ = 0.95-1.00) and V/(V + Ni) ratios (0.71-0.86), as well as the lack of enrichment in redox-sensitive trace elements such as U, V, Zn, Pb, Cu, Ni, Cr, Co and Mn, together with the presence of overlying BIF, suggest that the Jingtieshan area represents a ferruginous deep-water succession. This, and intense submarine hydrothermal activities contributed to the deposition of the Jingtieshan BIF.

  9. Stability and mobility of Cu-vacancy clusters in Fe-Cu alloys: A computational study based on the use of artificial neural networks for energy barrier calculations

    An atomistic kinetic Monte Carlo (AKMC) method has been applied to study the stability and mobility of copper-vacancy clusters in Fe. This information, which cannot be obtained directly from experimental measurements, is needed to parameterise models describing the nanostructure evolution under irradiation of Fe alloys (e.g. model alloys for reactor pressure vessel steels). The physical reliability of the AKMC method has been improved by employing artificial intelligence techniques for the regression of the activation energies required by the model as input. These energies are calculated allowing for the effects of local chemistry and relaxation, using an interatomic potential fitted to reproduce them as accurately as possible and the nudged-elastic-band method. The model validation was based on comparison with available ab initio calculations for verification of the used cohesive model, as well as with other models and theories.

  10. Porphyry Cu-Au and associated polymetallic Fe-Cu-Au deposits in the Beiya Area, western Yunnan Province, south China

    Xu, X.-W.; Cai, X.-P.; Xiao, Q.-B.; Peters, S.G.

    2007-01-01

    The Alkaline porphyries in the Beiya area are located east of the Jinshajiang suture, as part of a Cenozoic alkali-rich porphyry belt in western Yunnan. The main rock types include quartz-albite porphyry, quartz-K-feldspar porphyry and biotite-K-feldspar porphyry. These porphyries are characterised by high alkalinity [(K2O + Na2O)% > 10%], high silica (SiO2% > 65%), high Sr (> 400??ppm) and 87Sr/86Sr (> 0.706)] ratio and were intruded at 65.5??Ma, between 25.5 to 32.5??Ma, and about 3.8??Ma, respectively. There are five main types of mineral deposits in the Beiya area: (1) porphyry Cu-Au deposits, (2) magmatic Fe-Au deposits, (3) sedimentary polymetallic deposits, (4) polymetallic skarn deposits, and (5) palaeoplacers associated with karsts. The porphyry Cu-Au and polymetallic skarn deposits are associated with quartz-albite porphyry bodies. The Fe-Au and polymetallic sedimentary deposits are part of an ore-forming system that produced considerable Au in the Beiya area, and are characterised by low concentrations of La, Ti, and Co, and high concentrations of Y, Yb, and Sc. The Cenozoic porphyries in western Yunnan display increased alkalinity away from the Triassic Jinshajiang suture. Distribution of both the porphyries and sedimentary deposits in the Beiya area are interpreted to be related to partial melting in a disjointed region between upper mantle lithosphere of the Yangtze Plate and Gondwana continent, and lie within a shear zone between buried Palaeo-Tethyan oceanic lithosphere and upper mantle lithosphere, caused by the subduction and collision of India and Asia. ?? 2006 Elsevier B.V. All rights reserved.

  11. Planar Hall effect bridge sensors with NiFe/Cu/IrMn stack optimized for self-field magnetic bead detection

    Henriksen, Anders Dahl; Rizzi, Giovanni; Hansen, Mikkel Fougt

    2016-01-01

    The stack composition in trilayer Planar Hall effect bridge sensors is investigated experimentally to identify the optimal stack for magnetic bead detection using the sensor self-field. The sensors were fabricated using exchange-biased stacks Ni80Fe20(tFM)/Cu(tCu)/Mn80Ir20(10 nm) with tFM = 10, 20...... of the sensors and, thus, that the magnetic stacks should be compared at constant power consumption. For a fixed sensor geometry, the figure of merit for this comparison is the magnetic field sensitivity normalized by the sensor bias voltage. In this regard, we found that sensors with tFM = 20 nm or...

  12. Planar Hall effect bridge sensors with NiFe/Cu/IrMn stack optimized for self-field magnetic bead detection

    Henriksen, Anders Dahl; Rizzi, Giovanni; Hansen, Mikkel Fougt

    2016-03-01

    The stack composition in trilayer Planar Hall effect bridge sensors is investigated experimentally to identify the optimal stack for magnetic bead detection using the sensor self-field. The sensors were fabricated using exchange-biased stacks Ni80Fe20(tFM)/Cu(tCu)/Mn80Ir20(10 nm) with tFM = 10, 20, and 30 nm, and 0 ≤ tCu ≤ 0.6 nm. The sensors were characterized by magnetic hysteresis measurements, by measurements of the sensor response vs. applied field, and by measurements of the sensor response to a suspension of magnetic beads magnetized by the sensor self-field due to the sensor bias current. The exchange bias field was found to decay exponentially with tCu and inversely with tFM. The reduced exchange field for larger values of tFM and tCu resulted in higher sensitivities to both magnetic fields and magnetic beads. We argue that the maximum magnetic bead signal is limited by Joule heating of the sensors and, thus, that the magnetic stacks should be compared at constant power consumption. For a fixed sensor geometry, the figure of merit for this comparison is the magnetic field sensitivity normalized by the sensor bias voltage. In this regard, we found that sensors with tFM = 20 nm or 30 nm outperformed those with tFM = 10 nm by a factor of approximately two, because the latter have a reduced AMR ratio. Further, the optimum layer thicknesses, tCu ≈ 0.6 nm and tFM = 20-30 nm, gave a 90% higher signal compared to the corresponding sensors with tCu = 0 nm.

  13. The coercivity dependence of giant magneto-impedance effect in Fe-Cu-Nb-Si-B based metallic alloy ribbon at different crystalline stages

    We have studied the giant magneto-impedance (GMI) effect in one Fe-based FINEMET alloy ribbon with nominal composition Fe73.5Cu1Nb3Si13.5B9 (at %). DTA experiments were conducted to identify the primary and secondary crystallization temperatures. XRD, SEM and EDAX were performed to identify the phases at various crystalline stages. Static magnetic properties of the ribbons were measured using a VSM. Coercivity was found to be a strong function of annealing temperature, and this, in turn depended on the size and type of the crystalline phases. The maximum MI effect of 103.4% was observed at annealing temperature of 600 deg. C. It was found that a small change in DC coercivity as a result of annealing greatly changed the MI ratios of the crystalline ribbons. Annealing above the secondary crystallization temperature caused the precipitation of Fe2B and Fe3B phases, which induced magnetic hardening and eliminates MI sensitivity

  14. Review paper: Magnetocaloric effects in RTX intermetallic compounds (R = Gd~Tm, T = Fe~Cu and Pd, X = Al and Si)

    Hu, Zhang; Bao-Gen, Shen

    2015-01-01

    The ternary intermetallic RTX compounds (R = rare earth, T = transitional metal, X = p-block metal) have been investigated extensively in the past few decades due to their interesting physical properties. Recently, much attention has been paid to the magnetocaloric effect (MCE) of these RTX compounds, especially the ones with heavy rare-earth, for their potential application in low temperature magnetic refrigeration. In this paper, we review the MCE of RTSi and RTAl systems with R = Gd~Tm, T ...

  15. A lattice Monte Carlo simulation of nanophase compositions and structures in irradiated pressure vessel Fe-Cu-Ni-Mn-Si steels

    A self-consistent analysis, combining thermodynamic calculations, recent small angle neutron scattering and atom probe field ion microscopy measurements and lattice Monte Carlo (LMC) simulations, is used to characterize the ultra fine coherent precipitates that form in irradiated reactor pressure vessel steels. These nanofeatures are typically rich in impurity copper precipitated from highly supersaturated solution at vessel operating temperatures around 300 C at rates greatly accelerated by radiation enhanced diffusion. Although some copper appears to be needed to catalyze their formation, manganese nickel-rich precipitates may replace copper-rich precipitates at high concentrations of these alloying elements and/or lower temperatures. Thermodynamic and kinetic models are generally consistent with observations on the number densities, sizes, compositions and nucleation, growth and coarsening behavior of the nanofeatures. However, the LMC atomic scale simulations of complex nanofeature structures are needed to fully unify experiment and theory. (orig.)

  16. Thermodynamic estimation of minor element distribution between immiscible liquids in Fe-Cu-based metal phase generated in melting treatment of municipal solid wastes.

    Lu, X; Nakajima, K; Sakanakura, H; Matsubae, K; Bai, H; Nagasaka, T

    2012-06-01

    Waste electrical and electronic equipment (WEEE) has become an important target in managing material cycles from the viewpoint of not only waste management and control of environmental pollution but also resource conservation. This study investigated the distribution tendency of trace elements in municipal solid waste (MSW) or incinerator ash, including valuable non-ferrous metals (Ni, Co, Cr, Mn, Mo, Ti, V, W, Zr), precious group metals (PGMs) originated from WEEE (Ag, Au, Pd, Pt), and others (Al, B, Pb, Si), between Fe-rich and Cu-rich metal phases by means of simple thermodynamic calculations. Most of the typical alloying elements for steel (Co, Cr, Mo, Nb, Ni, Si, Ti, V, and W) and Rh were preferentially distributed into the Fe-rich phase. PGMs, such as Au, Ag, and Pd, were enriched in the Cu-rich phase, whereas Pt was almost equally distributed into both phases. Since the primary metallurgical processing of Cu is followed by an electrolysis for refining, and since PGMs in crude copper have been industrially recovered from the resulting anode slime, our results indicated that Ag, Au, and Pd could be effectively recovered from MSW if the Cu-rich phase could be selectively collected. PMID:22370049

  17. In situ surface magneto-optical Kerr effect (s-MOKE) study of ultrathin soft magnetic FeCuNbSiB alloy films

    Herein we report on an in situ surface magneto-optical Kerr effect (s-MOKE) study of ion-beam-sputtered ultra-thin films of an amorphous Fe73.9Cu0.9Nb3.1Si13.2B8.9 (FINEMET) alloy with film growth that ranges from a fraction of a nm to a few tens of nms. Extrapolating the linear variation of the Kerr signal with film thickness suggests the absence of a magnetic dead layer at the substrate/FINEMET film interface, and hence the absence of any intermixing. The presence of a thin SiO2 film at the surface of the Si substrate may be responsible for preventing possible intermixing of Fe with Si to form nonmagnetic silicide. Close to the onset of ferromagnetic ordering, a steep increase in the coercive field with film thickness can be explained in terms of the Volmer–Weber growth of the film. Furthermore, the temperature dependence of the hysteresis loops of a 41 nm-thick FINEMET film has been studied. The Curie temperature of the amorphous film is found to be lower than that of a ribbon of the same composition. The origin of a uniaxial magnetic anisotropy in the as-prepared stage is attributed to the generation of some long-range stresses in the film, which are relieved close to the onset temperature for nanocrystallization. (paper)

  18. The association between content of the elements S, Cl, K, Fe, Cu, Zn and Br in normal and cirrhotic liver tissue from Danes and Greenlandic Inuit examined by dual hierarchical clustering analysis

    Laursen, Jens; Milman, Nils; Pind, N.;

    2014-01-01

    contents according to calculated similarities, one clustering elements according to correlation coefficients between the element contents, both using Euclidian distance and Ward Procedure. RESULTS: One dendrogram separated subjects in 7 clusters showing no differences in ethnicity, gender or age. The...... analysis discriminated between elements in normal and cirrhotic livers. The other dendrogram clustered elements in four clusters: sulphur and chlorine; copper and bromine; potassium and zinc; iron. There were significant correlations between the elements in normal liver samples: S was associated with Cl, K...

  19. The distribution of trace elements Ca, Fe, Cu and Zn and the determination of copper oxidation state in breast tumour tissue using {mu}SRXRF and {mu}XANES

    Farquharson, M J; Al-Ebraheem, A [Department of Radiography, City Community and Health Sciences, City University, London, EC1V 0HB (United Kingdom); Falkenberg, G [Hamburger Synchrotronstrahlungslabor at Deutsches Elektronen-Synchrotron, DESY, Notkestr. 85, D-22603, Hamburg (Germany); Leek, R; Harris, A L [Cancer Research UK, Oxford Cancer Centre, Molecular Oncology Laboratories, University of Oxford, Weatherall Institute of Molecular Medicine, John Radcliffe Hospital, Oxford, 0X3 9DS (United Kingdom); Bradley, D A [Department of Physics, University of Surrey, Guildford, Surrey, GU2 7XH (United Kingdom)], E-mail: m.j.farquharson@city.ac.uk

    2008-06-07

    A micro beam synchrotron x-ray fluorescence ({mu}SRXRF) technique has been used to determine the localization of metals in primary invasive ductal carcinoma of breast. Nine samples were examined, all of which were formalin fixed tissues arranged as micro arrays of 1.0 mm diameter and 10 {mu}m thickness. Cu was the particular interest in this study although 2D maps of the elements Ca, Fe and Zn, which are also of physiological importance, are presented. The distribution of these metals was obtained at approximately 18 {mu}m spatial resolution and compared with light transmission images of adjacent sections that were H and E stained to reveal the location of the cancer cell clusters. Correlations were found between these reference images and the elemental distributions indicating an increase in all element concentrations in the tumour regions of all samples, with the exception of Fe, which in some cases showed a reverse of this trend. On average over all samples the percentage difference from the normal tissue elemental concentrations are Ca {approx} 67%, Cu {approx} 64% and Zn {approx} 145%. Micro x-ray absorption near edge spectroscopy ({mu}XANES) was used to estimate the oxidation state of Cu in 19 normal and 17 tumour regions spread over five samples. The shape and the position of both normal and tumour regions suggest that they contain mixtures of copper ions with a significant fraction of Cu{sup 2+}. However, the shape of the spectra does not exclude the presence of Cu{sup +}. Tumour regions were found to have a higher fraction of Cu{sup +} compared to the normal samples.

  20. On the influence of a microstructure on the cyclic durability of microlaminates of Fe/Cu, Mo/Cu, and dispersion-hardened Ni-Cr-Al2O3 materials

    Experimental dependences of the cyclic durability of microlayered and dispersion-hardened materials and aluminum alloys on the parameters of their microstructure are considered. On the basis of the ideas of the kinetic theory of strength, an equation describing the dependence of the durability on the parameters of a structure in the form of the Thompson-Beckofen equation is got

  1. Variational-average-atom-in-quantum-plasmas (VAAQP) code and virial theorem: equation-of-state and shock-Hugoniot calculations for warm dense Al, Fe, Cu, and Pb.

    Piron, R; Blenski, T

    2011-02-01

    The numerical code VAAQP (variational average atom in quantum plasmas), which is based on a fully variational model of equilibrium dense plasmas, is applied to equation-of-state calculations for aluminum, iron, copper, and lead in the warm-dense-matter regime. VAAQP does not impose the neutrality of the Wigner-Seitz ion sphere; it provides the average-atom structure and the mean ionization self-consistently from the solution of the variational equations. The formula used for the electronic pressure is simple and does not require any numerical differentiation. In this paper, the virial theorem is derived in both nonrelativistic and relativistic versions of the model. This theorem allows one to express the electron pressure as a combination of the electron kinetic and interaction energies. It is shown that the model fulfills automatically the virial theorem in the case of local-density approximations to the exchange-correlation free-energy. Applications of the model to the equation-of-state and Hugoniot shock adiabat of aluminum, iron, copper, and lead in the warm-dense-matter regime are presented. Comparisons with other approaches, including the inferno model, and with available experimental data are given. This work allows one to understand the thermodynamic consistency issues in the existing average-atom models. Starting from the case of aluminum, a comparative study of the thermodynamic consistency of the models is proposed. A preliminary study of the validity domain of the inferno model is also included. PMID:21405914

  2. Post-irradiation annealing behavior of neutron-irradiated FeCu, FeMnNi and FeMnNiCu model alloys investigated by means of small-angle neutron scattering

    Bergner, F. [Helmholtz-Zentrum Dresden-Rossendorf, POB 510119, 01314 Dresden (Germany); Ulbricht, A., E-mail: a.ulbricht@hzdr.de [Helmholtz-Zentrum Dresden-Rossendorf, POB 510119, 01314 Dresden (Germany); Lindner, P. [Institut Laue-Langevin Grenoble, BP 156, 38042 Grenoble Cedex 9 (France); Keiderling, U. [Helmholtz-Zentrum Berlin, Hahn-Meitner-Platz 1, 14109 Berlin (Germany); Malerba, L. [SCK-CEN Mol, Boeretang 200, 2400 Mol (Belgium)

    2014-11-15

    Neutron irradiation of reactor pressure vessel steels gives rise to the formation of thermodynamically stable and unstable nano-features. The present work is focused on the stability of Cu-, Mn- and Ni-containing solute clusters in model alloys exposed to post-irradiation annealing. Fe0.1Cu, Fe1.2Mn0.7Ni and Fe1.2Mn0.7Ni0.1Cu (wt%) model alloys irradiated up to neutron exposures of 0.1 and 0.19 dpa (displacements per atom) were annealed at stepwise increasing temperatures in the range from 300 °C (i.e. near irradiation temperature) to 500 °C and characterized by means of small-angle neutron scattering (SANS). We have found characteristic differences in the annealing behavior of the alloys. In particular, there is a non-trivial (synergistic–antagonistic) interplay of Mn/Ni and Cu.

  3. Leaching of S, Cu, and Fe from disseminated Ni-(Fe)-(Cu) sulphide ore during serpentinization of dunite host rocks at Mount Keith, Agnew-Wiluna belt, Western Australia

    Gole, Martin J.

    2014-10-01

    Komatiite-hosted disseminated Ni sulphide deposits in the Agnew-Wiluna greenstone belt occur both above and below the olivine isograd that was imposed on the greenstone sequence during the M2 metamorphic/deformation event. Deposits in the northern and central part of the belt and that are located below the isograd (Mount Keith, Honeymoon Well and West Jordan) have complex sulphide mineralogy and strongly zoned sulphide assemblages. These range from least-altered assemblages of pentlandite-pyrrhotite-chalcopyrite±pyrite to altered assemblages of pentlandite±chalcopyrite, pentlandite-heazlewoodite (or millerite), heazlewoodite (or millerite), and rarely to heazlewoodite-native Ni. Deposits to the south and that are above of the olivine isograd (Six Mile, Goliath North) are dominated by less complex magmatic assemblages with a lower proportion of weakly altered pentlandite±chalcopyrite assemblages. More altered assemblages are uncommon in these deposits and occur as isolated patches around the periphery of the deposits. The sulphide zonation is reflected by whole-rock reductions in S, Cu, Fe and Zn, whereas Ni, Pt and Pd and, with some exceptions, Co are conservative. The leaching of S, Cu, Fe and Zn from sulphide assemblages and the whole rock was initiated by highly reduced conditions that were produced during low fluid/rock ratio serpentinization. Consumption of H2O resulted in Cl, a component of the fluid, being concentrated sufficiently to stabilise iowaite as part of lizardite-rich assemblages. Once the rate of olivine hydration reactions declined and during and after expansion and associated fracturing of the ultramafic sequence allowed higher fluid access, a more fluid-dominated environment formed and new carbonate-bearing fluid gained access to varying extents to the ultramafic rock sequence. This drove Cl from iowaite (to form pyroaurite) and caused the sulphide assemblages to be altered from the original magmatic assemblages and compositions to those stable at the prevailing fO2 and fS2 conditions. Mass transfer was made possible via metal chloride complexes and H2S with fluids driven by deformation associated with the M2 metamorphism. Disseminated deposits in higher metamorphic grade terrains where olivine was stable during peak metamorphism did not undergo the metasomatism seen in the deposits in areas of lower metamorphic grade. Some minor leaching of S, Fe and Cu occurred around the periphery of the deposits during early, pre-M2 peak metamorphism, but once olivine stability was reached the driving force for the series of leaching reactions was exhausted. The effect of this process on the original magmatic sulphides is to induce significant variability in texture, mineralogy and bulk composition and to markedly reduce the Fe and S contents of the sulphide fraction (in extreme cases to zero for both elements), and to reduce the volume of the sulphide fraction per unit of Ni. These changes impact unfavourably on Ni sulphide recoveries and metallurgical characteristics of these Ni ores.

  4. A magnetic study of ThCr2Si2-type pseudo-ternary RMn1.5T0.5Ge2 compounds. (R=Y,Ce-Sm,Gd-Ho; T=Fe,Cu)

    We report on bulk magnetization measurements performed on ThCr2Si2-type RMn1.5T0.5Ge2 compounds (R=Y, La-Nd, Sm, Gd-Ho; T=Cu, Fe). These pseudo-ternary compounds display largely correlated variations of their magnetic transition temperatures. This phenomenon might be related to magnetic properties based on competing in-plane and inter-plane Mn-Mn interactions. The RMn1.5Cu0.5Ge2 compounds are characterized by relatively large magnetocrystalline anisotropy. (orig.)

  5. The distribution of trace elements Ca, Fe, Cu and Zn and the determination of copper oxidation state in breast tumour tissue using μSRXRF and μXANES

    A micro beam synchrotron x-ray fluorescence (μSRXRF) technique has been used to determine the localization of metals in primary invasive ductal carcinoma of breast. Nine samples were examined, all of which were formalin fixed tissues arranged as micro arrays of 1.0 mm diameter and 10 μm thickness. Cu was the particular interest in this study although 2D maps of the elements Ca, Fe and Zn, which are also of physiological importance, are presented. The distribution of these metals was obtained at approximately 18 μm spatial resolution and compared with light transmission images of adjacent sections that were H and E stained to reveal the location of the cancer cell clusters. Correlations were found between these reference images and the elemental distributions indicating an increase in all element concentrations in the tumour regions of all samples, with the exception of Fe, which in some cases showed a reverse of this trend. On average over all samples the percentage difference from the normal tissue elemental concentrations are Ca ∼ 67%, Cu ∼ 64% and Zn ∼ 145%. Micro x-ray absorption near edge spectroscopy (μXANES) was used to estimate the oxidation state of Cu in 19 normal and 17 tumour regions spread over five samples. The shape and the position of both normal and tumour regions suggest that they contain mixtures of copper ions with a significant fraction of Cu2+. However, the shape of the spectra does not exclude the presence of Cu+. Tumour regions were found to have a higher fraction of Cu+ compared to the normal samples

  6. Geoquímica de las Aguas del Río Elqui y de sus Tributarios en el Período 1975-1995: Factores Naturales y Efecto de las Explotaciones Mineras en sus Contenidos de Fe, Cu y As Water Geochemistry of the Elqui River and its Tributaries in the Period 1975-1995: Natural Factors and Effect of Mining Activities on its Fe, Cu and As Contents

    Samuel Guevara G

    2006-03-01

    Full Text Available El presente trabajo expone y discute los resultados de veinte años (1975-1995 de análisis de aguas del Río Elqui y sus tributarios, realizados por la Dirección General de Aguas. Su discusión se complementa con la de resultados de estudios recientes de la geoquímica de los sedimentos de la misma cuenca. Entre sus principales conclusiones destaca la alta concentración de Cu y As de los ríos Toro, Turbio y Elqui, que reciben el aporte directo (Río Toro o indirecto de las aguas del Río Malo, que drena la zona de alteraciones hidrotermales y mineralizaciones de Au-Cu-As del distrito minero de El Indio. La intensificación de las faenas minero-metalúrgicas de El Indio coincidió con incrementos en los contenidos de As y Cu de los ríos Toro, Turbio y Elqui, aunque los de As son progresivamente atenuados por el efecto de dilución debido al aporte de ríos tributarios pobres en ese elemento. Por otra parte, el Río Elqui ha recibido aportes significativos de Cu provenientes del distrito minero de Talcuna, situado en la Quebrada Marquesa. Aunque las actividades mineras de El Indio contribuyeron probablemente a aumentar el contenido de As, Cu y Fe de las aguas, estos y otros metales pesados han estado presentes en las aguas afectadas por drenaje ácido del Río Malo desde mucho tiempo antes de que dichas actividades se iniciaran. Igualmente, el Río Malo continuará siendo una fuente contaminante después del cierre - ya completado - del distrito minero de El Indio.The present study discusses the results of 20 years (1975-1995 of chemical analysis of waters of the Elqui river and its tributaries, performed by the Dirección General de Aguas - the national waters authority. This discussion is complemented with the results of recent studies of the geochemistry of the sediment of its basin. Among the principal conclusions attained, are the high contents of Cu and As of the Toro, Turbio and Elqui rivers, that receive a direct (Toro river or indirect contribution of the Malo river, which drains the hydrothermal alteration zone of the Au-Cu-As deposits of the El Indio mining district. The growing intensification of the mining and metallurgical activities at El Indio coincided with increasing contents of Cu and As in the Toro, Turbio and Elqui rivers, though they are progressively attenuated for As due to the diluent effects of low-mineralized tributary river waters. On the other hand, the Elqui river has received significant amounts of Cu from the Talcuna mining district in the Quebrada Marquesa ravine. Though the mining activities at El Indio probably contributed to the increase in As, Cu and Fe contents of the waters, these and other heavy metals have been present in the acid drainage water of the Malo river long before the beginning of said activities. Likewise, the Malo river will continue to be a pollution source after the closure - already completed -of the El Indio mining district.

  7. Structure and Strength of Iron-Copper-Carbon Nanotube Nanocomposites

    Boshko, Oleh; Dashevskyi, Mykola; Mykhaliuk, Olga; Ivanenko, Kateryna; Hamamda, Smail; Revo, Sergiy

    2016-01-01

    Nanocomposite materials of the Fe-Cu system with/without small addition of carbon nanotubes have been synthesized by mechanochemical activation of elemental Fe and Cu powders in a high-energy planetary ball mill and have been examined by the X-ray diffraction method, SEM and the thermopower methods; the tensile strength of the materials obtained has been estimated. The metastable (Fe, Cu) supersaturated solid solution is formed in the Fe-Cu nanocomposites during milling process. The coherent ...

  8. Recovery of zinc and manganese, and other metals (Fe, Cu, Ni, Co, Cd, Cr, Na, K) from Zn-MnO2 and Zn-C waste batteries: Hydroxyl and carbonate co-precipitation from solution after reducing acidic leaching with use of oxalic acid

    Sobianowska-Turek, A.; Szczepaniak, W.; Maciejewski, P.; Gawlik-Kobylińska, M.

    2016-09-01

    The article discusses the current situation of the spent batteries and portable accumulators management. It reviews recycling technologies of the spent batteries and portable accumulators which are used in the manufacturing installations in the world. Also, it presents the authors' research results on the reductive acidic leaching of waste material of the zinc-carbon batteries (Zn-C) and zinc-manganese batteries (alkaline Zn-MnO2) delivered by a company dealing with mechanical treatment of this type of waste stream. The research data proved that the reductive acidic leaching (H2SO4 + C2H2O4) of the battery's black mass allows to recover 85.0% of zinc and 100% of manganese. Moreover, it was found that after the reductive acidic leaching it is possible to recover nearly 100% of manganese, iron, cadmium, and chromium, 98.0% of cobalt, 95.5% of zinc, and 85.0% of copper and nickel from the solution with carbonate method. On the basis of the results, it is possible to assume that the carbonate method can be used for the preparation of manganese-zinc ferrite.

  9. Fe-Cu二元互不溶体系中纳米晶过饱和固溶体的机械合金化制备研究进展%Research progress on mechanical alloying preparation of nanocrystalline supersaturated solid solution in Fe-Cu immiscible system

    吴志方; 周帆

    2015-01-01

    Fe-Cu二元互不溶体系合金在机械合金化过程中形成纳米晶过饱和固溶体,并显示出与其微米尺度结构合金所不同的独特性能.综述了近年来Fe-Cu二元互不溶体系中纳米晶过饱和固溶体的机械合金化研究进展,着重介绍了Fe-Cu纳米晶过饱和固溶体的形成机理及其力学和物理性能等.

  10. Structure and Strength of Iron-Copper-Carbon Nanotube Nanocomposites

    Boshko, Oleh; Dashevskyi, Mykola; Mykhaliuk, Olga; Ivanenko, Kateryna; Hamamda, Smail; Revo, Sergiy

    2016-02-01

    Nanocomposite materials of the Fe-Cu system with/without small addition of carbon nanotubes have been synthesized by mechanochemical activation of elemental Fe and Cu powders in a high-energy planetary ball mill and have been examined by the X-ray diffraction method, SEM and the thermopower methods; the tensile strength of the materials obtained has been estimated. The metastable (Fe, Cu) supersaturated solid solution is formed in the Fe-Cu nanocomposites during milling process. The coherent scattering block size of the materials obtained is decreased with increase of milling time. The duration of mechanochemical activation affects the physical properties of nanocomposites studied. Addition of a small amount of nanotubes into Fe-Cu charge results in a significant increase of strength of the Fe-Cu (4:1) + CNT nanocomposite materials (NCMs) obtained.

  11. Structure and Strength of Iron-Copper-Carbon Nanotube Nanocomposites.

    Boshko, Oleh; Dashevskyi, Mykola; Mykhaliuk, Olga; Ivanenko, Kateryna; Hamamda, Smail; Revo, Sergiy

    2016-12-01

    Nanocomposite materials of the Fe-Cu system with/without small addition of carbon nanotubes have been synthesized by mechanochemical activation of elemental Fe and Cu powders in a high-energy planetary ball mill and have been examined by the X-ray diffraction method, SEM and the thermopower methods; the tensile strength of the materials obtained has been estimated. The metastable (Fe, Cu) supersaturated solid solution is formed in the Fe-Cu nanocomposites during milling process. The coherent scattering block size of the materials obtained is decreased with increase of milling time. The duration of mechanochemical activation affects the physical properties of nanocomposites studied. Addition of a small amount of nanotubes into Fe-Cu charge results in a significant increase of strength of the Fe-Cu (4:1) + CNT nanocomposite materials (NCMs) obtained. PMID:26858160

  12. Concentrations of Heavy Metals in Macrobrachium vollenhovenii (Herklots, 1857) from Epe Lagoon, Lagos, Nigeria

    Jimoh, A. A; E.O. Clarke, P.E. Ndimele, C.A. Kumolu-Johnson and F.A. Adebayo

    2011-01-01

    The levels of five metals, Fe, Cu, Zn, Cr and Pb in Macrobrachium vollenhovenii from Epe Lagoon were investigated from March, 2008 to December, 2008. The monthly concentrations of the metals varied significantly (p

  13. Buried nodules and associated sediments from the central Indian Basin

    Banerjee, R.; Iyer, S.D.; Dutta, P.

    ) at different depths show variable abundances of micronodules, volcanic glass shards and biodebris. Dissolution of biodebris increases and abundance of micronodules decreases with increasing depth. Enrichment in Mn, Fe, Cu, Ni, Co, together with a decrease...

  14. Variation in size, morphology and chemical composition of polymetallic nodules from the Central Indian Ocean Basin

    Valsangkar, A.B.; Karisiddaiah, S.M.; Parthiban, G.

    Chemical composition of 613 polymetallic nodules from 150 stations in the Central Indian Ocean Basin (CIOB) are determined and variations in Mn, Fe, Cu, Ni, Co, Zn and moisture content are studied with respect to their size and surface texture...

  15. Electron irradiation-induced mechanical property changes in reactor pressure vessel alloys

    Alexander, D.E.; Rehn, L.E. [Argonne National Lab., IL (United States); Odette, G.R.; Lucas, G.E. [California Univ., Santa Barbara, CA (United States). Dept. of Mechanical Engineering

    1995-11-01

    High-energy electrons were used to study tensile property changes in simple Fe-Cu and Fe-Cu-Mn alloys irradiated at 288C. A comparison was made with neutron irradiation data on the same alloys. An apparent effect of alloy chemistry was observed in which the presence of Mn affected embrittlement differently for electron and neutron irradiation. Comparison of previous experimental studies with the present experimental results indicates that electrons may be more efficient than fast neutrons at producing embrittlement.

  16. Electron irradiation-induced mechanical property changes in reactor pressure vessel alloys

    High-energy electrons were used to study tensile property changes in simple Fe-Cu and Fe-Cu-Mn alloys irradiated at 288C. A comparison was made with neutron irradiation data on the same alloys. An apparent effect of alloy chemistry was observed in which the presence of Mn affected embrittlement differently for electron and neutron irradiation. Comparison of previous experimental studies with the present experimental results indicates that electrons may be more efficient than fast neutrons at producing embrittlement

  17. Magnetoimpedance in amorphous/metal/amorphous sandwiched films at GHz frequencies

    Correa, M.A. [Departamento de Fisica, CCNE, UFSM, 97105-900, Santa Maria, RS (Brazil)]. E-mail: mmacorrea@gmail.com; Viegas, A.D.C. [Departamento de Fisica, CCNE, UFSM, 97105-900, Santa Maria, RS (Brazil); Silva, R.B. da [Departamento de Fisica, CCNE, UFSM, 97105-900, Santa Maria, RS (Brazil); Andrade, A.M.H. de [Departamento de Fisica, CCNE, UFSM, 97105-900, Santa Maria, RS (Brazil); Sommer, R.L. [Centro Brasileiro de Pesquisas Fisicas, 22290-180, Rio de Janeiro, RJ (Brazil)

    2006-10-01

    In this work, we report a comparative study of the magnetoimpedance in sandwiched films with the structure FS/Cu/FS (SWS) and FM/Cu/FM (SWM) where FS=single-layer FeCuNbSiB and FM=multilayer FeCuNbSiB/Cu. Magnetoimpedance ratios of 250% were obtained for the real part of the impedance in the SWM sample, while variations of 100% were reached for the SWS sample.

  18. Phase separation and rapid solidification of liquid Cu60Fe30Co10 ternary peritectic alloy

    DAI FuPing; CAO ChongDe; WEI BingBo

    2007-01-01

    The metastable liquid phase separation and rapid solidification of Cu60Fe30Co10 ternary peritectic alloy were investigated by using the drop tube technique and the differential scanning calorimetry method. It was found that the critical temperature of metastable liquid phase separation in this alloy is 1623.5 K, and the two separated liquid phases solidify as Cu(Fe,Co) and Fe(Cu,Co) solid solutions, respectively. The undercooling and cooling rate of droplets processed in the drop tube increase with the decrease of their diameters. During the drop tube processing, the structural morphologies of undercooled droplets are strongly dependent on the cooling rate. With the increase of the cooling rate, Fe(Cu,Co) spheres are refined greatly and become uniformly dispersed in the Cu-rich matrix. The calculations of Marangoni migration velocity (VM) and Stokes motion velocity (VS) of Fe(Cu,Co) droplets indicated that Marangoni migration contributes more to the coarsening and congregation of the minor phase during free fall. At the same undercooling, the VM/VS ratio increases drastically as Fe(Cu,Co) droplet size decreases. On the other hand, a larger undercooling tends to increase the VM/VS value for Fe(Cu,Co) droplets with the same size.

  19. Release of Heavy Metals from the Pyrite Tailings of Huangjiagou Pyrite Mine: Batch Experiments

    Liangqian Fan

    2016-01-01

    Full Text Available To provide the basic information about the release of heavy metals from the pyrite tailings of Huangjiagou pyrite mine, the pyrite tailings were investigated through a series of batch experiments under different initial pH of extractant, temperature, liquid-solid (LS ratio, and soaking time conditions. Moreover, calcium carbonate was added in the pyrite tailings to determine the reduction effect on the release of heavy metals. The results show that Fe, Cr, Cu, Mn, Zn, and Ni were the major heavy metals in the pyrite tailings. Low initial pH and high LS ratio significantly promoted Fe, Cu, Mn, Ni, and Zn release, and high temperature significantly promoted Fe, Cu, Mn, and Ni release. Only small amounts of Cr were detected at low LS ratios. With the increase of soaking time, the released amount of Fe, Cu, Mn, Ni, and Zn increased to the maximum value within 48 h, respectively. After adding calcium carbonate, the released amounts of Fe, Cu, and Zn reduced at least 70.80% within 48 h soaking time. The results indicate that summer and the early soaking stage are the main phases for the release of heavy metals from the pyrite tailings. In the pyrite tailings, Cr is difficult to release. Adding calcium carbonate can effectively reduce the release of Fe, Cu, and Zn.

  20. Structure and soft magnetic properties of the bulk samples prepared by compaction of the mixtures of Co-based and Fe-based powders

    Ball milling of CoFeZrB ribbons and subsequent compaction of the resulting powders were used to prepare bulk amorphous samples. Further, two sets of powder samples were prepared by cryomilling of FeCuNbMoSiB alloy in amorphous and nanocrystalline state. Amorphous and nanocrystalline FeCuNbMoSiB powders were blended with CoFeZrB powder at different concentrations. Such powder mixtures were consolidated and several bulk nanocomposites have been synthesized. An addition of nanocrystalline or amorphous FeCuNbMoSiB powder to amorphous CoFeZrB powder caused a decrease of the magnetostriction of the resultant bulk samples, while the coercivity shows an opposite behavior. Our results show that the powder consolidation by hot pressing is an alternative method for the preparation of bulk metallic glasses, which are difficult to prepare by casting methods

  1. Kinetic process of mechanical alloying in Fe50Cu50

    Huang, J.Y.; Jiang, Jianzhong; Yasuda, H.;

    1998-01-01

    It is shown that mechanical alloying in the immiscible Fe-Cu system is governed by the atomic shear event and shear-induced diffusion process. We found that an alpha-to-gamma phase transformation, as evidenced by the Nishiyama-Wasserman orientation relationship, occurs by simultaneous shearing pr...... structures, until a complete fee Fe-Cu solid solution is formed. The results provide significant insight into the understanding of recent experiments showing that chemical mixing of immiscible elements can bd induced by mechanical alloying. [S0163-1829(98)51342-2]....

  2. Effects of aging time and temperature of Fe-1wt.%Cu on magnetic Barkhausen noise and FORC

    Muad Saleh; Yue Cao; Edwards, Danny J; Pradeep Ramuhalli; Johnson, Bradley R.; McCloy, John S.

    2016-01-01

    Magnetic Barkhausen noise (MBN), hysteresis measurements, first order reversal curves (FORC), Vickers microhardness, and Transmission Electron Microscopy (TEM) analyses were performed on Fe-1wt.%Cu (Fe-Cu) samples isothermally aged at 700°C for 0.5 – 25 hours to obtain samples with different sized Cu precipitates and dislocation structures. Fe-Cu is used to simulate the thermal and irradiation-induced defects in copper-containing nuclear reactor materials such as cooling system pipes and pres...

  3. Growth of Photosynthetic Bio films and Fe, Pb, Cu, and Zn Speciation in Unsaturated Columns with Calcareous Mine Tailings from Arid Zones

    Mine tailing remediation aims to reduce the rate of sulfide mineral oxidation. Earlier studies showed that photosynthetic bio films may act as a physical barrier against oxygen diffusion. Currently, a long-term assay (6 months) is required to evaluate the solid phase redistribution of the Pb, Fe, Cu, and Zn originally present in historic and calcareous mine tailing samples (in our case from a semiarid region in North-Central Mexico). The presence of bio films may provide chemical gradients and physical conditions that shift the proportion of Fe, Cu, and Zn originally associated with oxides to carbonates and organic matter/sulfide fractions.

  4. Actividad catalítica de metales de transición en la descomposición de peróxido de hidrógeno

    José G. Carriazo; Luis. F. Bossa-Benavides; Eliana Castillo

    2012-01-01

    This paper compares the catalytic activities of some transition metal ions (Fe3+, Co2+, Cu2+, Ni2+, Zn2+) in the H2O2 decomposition in homogenous and heterogeneous processes, including solid mixed systems (Fe-Cu-Co/Al2O3, Fe-Cu/Al2O3, Fe-Co/Al2O3 and Co-Cu/Al2O3). The solids were characterised by X-ray diffraction to explore evolution of phases or possible changes. Different trends of the catalytic activity were observed: in homogeneous medium the most active species was Fe3+, whereas in hete...

  5. Growth of Photosynthetic Biofilms and Fe, Pb, Cu, and Zn Speciation in Unsaturated Columns with Calcareous Mine Tailings from Arid Zones

    J. V. García-Meza

    2011-01-01

    Full Text Available Mine tailing remediation aims to reduce the rate of sulfide mineral oxidation. Earlier studies showed that photosynthetic biofilms may act as a physical barrier against oxygen diffusion. Currently, a long-term assay (6 months is required to evaluate the solid phase redistribution of the Pb, Fe, Cu, and Zn originally present in historic and calcareous mine tailing samples (in our case from a semiarid region in North-Central Mexico. The presence of biofilms may provide chemical gradients and physical conditions that shift the proportion of Fe, Cu, and Zn originally associated with oxides to carbonates and organic matter/sulfide fractions.

  6. Probing giant magnetoresistance with THz spectroscopy

    Jin, Zuanming; Tkach, Alexander; Casper, Frederick;

    2014-01-01

    We observe a giant magnetoresistance effect in CoFe/Cu-based multistack using THz time-domain spectroscopy. The magnetic field-dependent dc conductivity, electron scattering time, as well as spin-asymmetry parameter of the structure are successfully determined. © 2014 OSA.......We observe a giant magnetoresistance effect in CoFe/Cu-based multistack using THz time-domain spectroscopy. The magnetic field-dependent dc conductivity, electron scattering time, as well as spin-asymmetry parameter of the structure are successfully determined. © 2014 OSA....

  7. Industrial Wastewater Treatment Using Local Natural Soil in Abu Dhabi, U.A.E

    H. A. Tayim; A. H. Al-Yazouri

    2005-01-01

    Local soil from the Emirate of Abu Dhabi, United Arab Emirate is investigated for its efficiency in removing heavy metals from industrial wastewater. Eight different industrial water effluents from different industries were treated. Pb, Zn, Fe, Cu and Mn were removed from industrial wastewaters yielding treated water with heavy metal concentrations well below the maximum limits enforced by environmental protection agencies.

  8. Synthesis of higher alcohols over highly dispersed Cu-Fe based catalysts derived from layered double hydroxides.

    Han, Xinyou; Fang, Kegong; Zhou, Juan; Zhao, Lu; Sun, Yuhan

    2016-05-15

    Highly dispersed Cu-Fe based catalysts with Fe/Cu molar ratios ranging from 0.2 to 1 were prepared via thermal decomposition of layered double hydroxides (LDHs) precursors and tested for higher alcohol synthesis (HAS) via CO hydrogenation. The catalysts were characterized using different techniques such as XRD, TEM, XPS, and H2-TPR. It was demonstrated that the Cu and Fe ions were highly dispersed in the brucite-like layers of the LDHs. With increased Fe/Cu atomic ratio, the tetrahedrally coordinated Cu ion content, Cu reduction temperatures, and the spacing of layers initially increase until the Fe/Cu ratio reaches 0.5 and then decrease. In addition to the catalytic evaluation for CO hydrogenation and catalyst characterization, the relationships between the physical-chemical properties of the catalysts and their catalytic performances were also investigated. It was also found that the alcohols/hydrocarbons ratios correlate linearly with the tetrahedrally coordinated Cu ion content. Moreover, higher reduction temperatures of Cu species as well as larger spacing between the layers in the catalyst are favorable for the synthesis of alcohols. The incorporation of a suitable amount of Fe is beneficial for the production of higher alcohols, with the best catalytic performance (alcohol selectivity of 20.77% and C2+ alcohol selectivity of 48.06%) obtained from a Fe/Cu atomic ratio of 0.5. PMID:26943001

  9. Physical properties and petrologic description of rock samples from an IOCG mineralized area in the northern Fennoscandian Shield, Sweden

    Sandrin, Alessandro; Edfelt, Å.; Waight, Tod Earle;

    2009-01-01

    The Tjårrojåkka Fe-Cu prospect in northern Sweden is considered an example of a Fe-oxide Cu-Au (IOCG) deposit and is hosted in metamorphosed Paleoproterozoic volcanic and intrusive rocks. Rock samples from 24 outcrops were collected for petrophysical analysis (magnetic susceptibility, remanent ma...

  10. Synchrotron radiation X-ray fluorescence analysis of Fe, Zn and Cu in mice brain associated with Parkinson’s disease

    田甜; 施继晔; 胡钧; 黄庆; 樊春海; 孙艳红

    2015-01-01

    The contents and distributions of metal elements in the brain are closely related to neurodegenerative diseases. In this study, we examined Fe, Cu and Zn contents in the brain section associated with Parkinson‘s disease (PD) using synchrotron radiation X-ray fluorescence (SRXRF). PD mouse model induced by 1-methyl-4-phenyl-1,2,3,6-terahydropyridine (MPTP) was used for the elemental analysis (e.g., Fe, Cu and Zn) in the substantia nigra pars compacta (SNpc) region of mice brain tissue samples. We found that mice in the MPTP group had higher contents of Fe, Cu and Zn in the SNpc than the control group. After treating the PD mice with rapamycin, the contents of Fe, Cu and Zn were reduced, the dopamine neurons and motor function were rescued correspondingly. The results prompted that the SRXRF provided an ideal method for tracing and analyzing the metal elements in the brain section to assess the pathological changes of PD model and the therapeutic effect of drugs.

  11. Mineral composition of some traditional Mexican teas.

    Laferriere, J E; Weber, C W; Kohlhepp, E A

    1991-07-01

    Teas of plant origin traditionally consumed by the Mountain Pima of Chihuahua, Mexico, were analyzed for mineral nutritional content. Fe, Cu, Zn, Ca, and Mg composition was determined for native teas made from shoots of Tagetes lucida, T. filifolia, Elytraria imbricata, and Holodiscus dumosus, and from root xylem of Ceanothus depressus and Phaseolus ritensis. Native uses of these teas are also described. PMID:1924192

  12. Metal analysis of cotton

    Seven varieties of cotton were investigated for 8 metal ions (K, Na, Mg, Ca, Fe, Cu, Zn, and Mn) using Inductively Coupled Plasma-Optical Emission Spectroscopy. All of the varieties were grown at the same location. Half of the samples were dry (rain fed only) and the other were well-watered (irrigat...

  13. Elements in normal and cirrhotic human liver. Potassium, iron, copper, zinc and bromine measured by X-ray fluorescence spectrometry

    Laursen, J.; Milman, N.; Leth, Peter Mygind;

    1990-01-01

    Various elements (K, Fe, Cu, Zn, Br) were measured by X-ray flourescence spectrometry in cellular and connective tissue fractions of normal and cirrhotic liver samples obtained at autopsy. Normal livers: 32 subjects (16 males, 16 females) median age 69 years. Cirrhotic livers: 14 subjects (13 males...

  14. Chemical dosimeter system for mixed neutron and gamma radiation

    G-values for the Fricke dosimeter and the FeCu dosimeter have been calculated for moderated fission neutrons. By combining these two chemical dosimeters, the fast neutron and gamma doses can be measured separately in a mixed field. (author). 7 refs, 2 tabs

  15. High-resolution electron microscopy observation and dislocation reaction mechanism of fivefold twinning in a Cu-rich precipitate in a cold rolled ferritic steel containing copper

    Ferritic steels containing copper have been studied as model systems for clusters/precipitate formation in reactor pressure vessel steels. The samples were aged at 400 °C for 4000 h and subsequently cold rolled to 30% reduction at room temperature. The microstructural characteristics of the samples were analyzed using high-resolution transmission electron microscopy. Direct evidence was found that the fivefold twinning occurs via simultaneous emission of two Shockley partial dislocations from two particular α-Fe/Cu interfaces, and then the pileup tips of the twofold twin. - Highlights: • Fivefold twin is observed in a Cu-rich precipitate in cold rolled ferritic steels. • A dislocation reaction mechanism for the fivefold twin formation is proposed. • Two particular mismatching α-Fe/Cu-rich precipitate interfaces play a critical role

  16. Formation mechanism of solute clusters under neutron irradiation in ferritic model alloys and in a reactor pressure vessel steel: clusters of defects

    The embrittlement of reactor pressure vessel (RPV) under irradiation is partly due to the formation of point defects (PD) and solute clusters. The aim of this work was to gain more insight into the formation mechanisms of solute clusters in low copper ([Cu] = 0.1 wt%) FeCu and FeCuMnNi model alloys, in a copper free FeMnNi model alloy and in a low copper French RPV steel (16MND5). These materials were neutron-irradiated around 300 C in a test reactor. Solute clusters were characterized by tomographic atom probe whereas PD clusters were simulated with a rate theory numerical code calibrated under cascade damage conditions using transmission electron microscopy analysis. The confrontation between experiments and simulation reveals that a heterogeneous irradiation-induced solute precipitation/segregation probably occurs on PD clusters. (author)

  17. Formation mechanism of solute clusters under neutron irradiation in ferritic model alloys and in a reactor pressure vessel steel: clusters of defects; Mecanismes de fragilisation sous irradiation aux neutrons d'alliages modeles ferritiques et d'un acier de cuve: amas de defauts

    Meslin-Chiffon, E

    2007-11-15

    The embrittlement of reactor pressure vessel (RPV) under irradiation is partly due to the formation of point defects (PD) and solute clusters. The aim of this work was to gain more insight into the formation mechanisms of solute clusters in low copper ([Cu] = 0.1 wt%) FeCu and FeCuMnNi model alloys, in a copper free FeMnNi model alloy and in a low copper French RPV steel (16MND5). These materials were neutron-irradiated around 300 C in a test reactor. Solute clusters were characterized by tomographic atom probe whereas PD clusters were simulated with a rate theory numerical code calibrated under cascade damage conditions using transmission electron microscopy analysis. The confrontation between experiments and simulation reveals that a heterogeneous irradiation-induced solute precipitation/segregation probably occurs on PD clusters. (author)

  18. Dried shiitake (Lentinulla edodes and oyster (Pleurotus ostreatus mushrooms as a good source of nutrient

    Julita Reguła

    2007-12-01

    Full Text Available Due to presented in literature potential health benefits of shiitake Lentinula edodes (Berk. Pegl. and oyster mushroom Pleurotus ostreatus (Jacq.: Fr. Kumm., chemical composition as well as Fe, Cu and Zn ions sorption (in conditions related to human digestive tract by dried shiitake and oyster were investigated. Both dried mushrooms had the high content of dietary fiber, Fe, Cu, Mg, K but low of fat, Na and Ca. Relatively low sorption of micronutrients was found in pH = 1.8, while the high sorption of Cu and Fe was observed in pH = 8.7. Dried mushrooms satisfied the maximum permissible level standards concerning toxic metals. The results of the research suggest that dried shiitake and oyster mushrooms can be used as additives in food products.

  19. Actividad catalítica de metales de transición en la descomposición de peróxido de hidrógeno

    José G. Carriazo

    2012-01-01

    Full Text Available This paper compares the catalytic activities of some transition metal ions (Fe3+, Co2+, Cu2+, Ni2+, Zn2+ in the H2O2 decomposition in homogenous and heterogeneous processes, including solid mixed systems (Fe-Cu-Co/Al2O3, Fe-Cu/Al2O3, Fe-Co/Al2O3 and Co-Cu/Al2O3. The solids were characterised by X-ray diffraction to explore evolution of phases or possible changes. Different trends of the catalytic activity were observed: in homogeneous medium the most active species was Fe3+, whereas in heterogeneous one the higher activities were shown for Co/Al2O3 and Co-Cu/Al2O3. A strong cooperative effect for the Co-Cu/Al2O3 system was observed, which can be considered as a new catalyst of interest for this type of reactions.

  20. Growth Mechanism of Single-Walled Carbon Nanotubes on Iron–Copper Catalyst and Chirality Studies by Electron Diffraction

    He, Maoshuai; Liu, Bilu; Chernov, Alexander I.;

    2012-01-01

    Chiralities of single-walled carbon nanotubes grown on an atomic layer deposition prepared bimetallic FeCu/MgO catalyst were evaluated quantitatively using nanobeam electron diffraction. The results reveal that the growth yields nearly 90% semiconducting tubes, 45% of which are of the (6,5) type....... The growth mechanisms as well as the roles of different components in the catalyst were studied in situ using environmental transmission electron microscopy and infrared spectroscopy. On the basis of the understanding of carbon nanotube growth mechanisms, an MgO-supported FeCu catalyst was prepared by...... impregnation, showing similar catalytic performance as the atomic layer deposition-prepared catalyst, yielding single-walled carbon nanotubes with a similar narrow chirality distribution....

  1. Thermal stability and the structure of vacancy–solute clusters in iron alloys

    Thermal stability and the structure of clusters formed by neutron irradiation are studied by means of positron annihilation spectroscopy of post-irradiation annealed FeCu, FeCuMnNi and FeMnNi alloys and rigid lattice calculations. While most of the vacancy–solute clusters dissolve in the temperature range between 650 K and 700 K, the presence of Ni and Mn solutes in vacancy–MnNi clusters provides an additional thermal stability and shifts the annealing stage corresponding to the dissociation of these clusters to higher temperature. Very good agreement between the measurements and calculations is obtained for vacancy–MnNi clusters of nanometric size, containing of about 25–50% of vacancies

  2. Study of the precipitation and of the hardening microscopic mechanisms under irradiation in dilute ferritic alloys; Etude de la precipitation et des mecanismes microscopiques de durcissement sous irradiation dans des alliages ferritiques dilues

    Mathon, M.H

    1995-07-01

    The copper precipitation plays a significant role in the embrittlement process of reactor vessel steels under neutron irradiation at 300 deg C. In order to understand the copper precipitation mechanisms, we have studied model ferritic binary FeCu and ternary alloys FeCuX (X=Mn,Ni, Cr, P). These materials have been either Irradiated with 2.5 MeV electrons In the 175-360 deg C temperature range or thermal aged at 500 deg C. The evolution of materials has been followed by resistivity measurements under irradiation, by small angle neutron scattering and by Vickers microhardness measurements. We have shown the similarity of copper precipitation under thermally ageing at 500 deg C and electron Irradiation at 300 deg C, in FeCu{sub 1,34%}. This result confirms that the main effect of electronic irradiation is to accelerate precipitation. Nevertheless, we have observed that irradiation induces an additional contribution to hardening attributed to point defect clusters. Concerning the ternary alloys, we observed that at 300 deg C the addition of a third element has no significant effect on the copper precipitation kinetic under irradiation but that at lower temperature manganese slows down precipitation kinetic. In order to reproduce the experimental results obtained on FeCu{sub 1,34%} by using a cluster kinetics model, we have to suppose that the precipitation is heterogeneous and controlled by interface reactions for the small size clusters. In addition, neutron or electron irradiated industrial steels have been studied by small angle neutron scattering. The results revealed the presence of nano-metric solute clusters which contain few copper atoms and which are not linked to the formation of displacement cascades. (author)

  3. Fe and Co nanostructures embedded into the Cu(100) surface: Self-Organization and magnetic properties

    Kolesnikov, S. V.; Klavsyuk, A. L.; Saletsky, A. M.

    2015-10-01

    The self-organization and magnetic properties of small iron and cobalt nanostructures embedded into the first layer of a Cu(100) surface are investigated using the self-learning kinetic Monte Carlo method and density functional theory. The similarities and differences between the Fe/Cu(100) and the Co/Cu(100) are underlined. The time evolution of magnetic properties of a copper monolayer with embedded magnetic atoms at 380 K is discussed.

  4. Mikronährstoffstatus und kognitive Leistung bei Patienten der Gedächtnisambulanz Ulm

    Hauel, Edith Maria

    2013-01-01

    Deficiency in micronutrients - vitamins and minerals - may add to impaired cognitive function and development of dementia in elderly. The objective of this study was to assess the micronutrient status and associated domain-specific cognitive performance of elderly out-patients of the memory clinic Ulm (Germany) with special focus on B-vitamins (B1, B6, folic acid, B12), antioxidant vitamins and provitamins (A, C, E, carotenes, lycopin), and redox-active minerals (Fe, Cu, Zn). Cognitive perfor...

  5. Interatomic potentials for materials of nuclear interest

    Procedures to develop embedded atom method (EAM) interatomic potentials are described, with foreseeable applications in nuclear materials. Their reliability is shown by evaluating relevant properties. The studied materials are Nb, Zr and U. The first two were then used to develop an inter species potential for the Zr-Nb binary system. In this sense, the Fe-Cu system was also studied starting from Fe and Cu potentials extracted from the literature. (author)

  6. IMPACT OF HEAVY METALS ON ANTIOXIDANT ACTIVITY IN DIFFERENT TISSUE OF MILK FISH Chanos chanos.

    Sivakumar Rajeshkumar,; Jayaprakash Mini,; Natesan Munuswamy

    2013-01-01

    The impact of heavy metal accumulation on antioxidant activity in Chanos chanos, (Milk fish) was studied in two different locations polluted sites (Kaattuppalli Island) and less polluted sites (Kovalam estuary). Accumulation of heavy metals in the gills, liver and muscles were observed Zn >Fe >Cu >Pb >Mn >Cd >Ni. The results reveal that highest concentration of metals in muscle, gills and liver were observed in Kaattuppalli Island when compared to Kovalam estuary. The antioxidant activity sho...

  7. Factors Governing concentration of platinum group elements in layered complexes

    Makovicky, E.; Rose-Hansen, J.; Karup-Møller, Sven; Makovicky, M.

    1996-01-01

    This report covers the synthetic research results obtained by the Danish group on: (1) The phase system Fe-Ir-S at 1100o, 1000o and 800oC, (2) Metal-rich portions of the phase system Pt-Ir-Fe-S: Pt-Fe-Ir alloys and associated sulfides at 1000oC and 1100oC, (3) The Fe (Cu)-Pt-Rh-S system: alloys a...

  8. Thermodynamic analysis of the change of solid solubility in a binary system processed by mechanical alloying

    Using a non-equilibrium process, it is possible to extend the solid solubility range in metallic systems. Therefore, the main objective of this work was to apply a thermodynamic model to predict the change in the solubility limit of systems with positive enthalpy mixing (Cu-Cr and Fe-Cu) processed by mechanical alloying. It was found that increasing the density of crystalline defects alters the solubility limit in these binary systems

  9. Determination of Cu/Zn and Fe in human serum of patients with sickle cell anemia using radiation synchrotron

    Canellas, C.G.L. [Nuclear Instrumentation Laboratory, COPPE/UFRJ, P.O. Box 68509, 21.941-972 Rio de Janeiro (Brazil); Carvalho, S.M.F. [State Institute of Hematology Arthur de Siqueira Cavalcanti, 20.211-030 Rio de Janeiro (Brazil); Anjos, M.J. [Nuclear Instrumentation Laboratory, COPPE/UFRJ, P.O. Box 68509, 21.941-972 Rio de Janeiro (Brazil); Physics Institute, State University of Rio de Janeiro, 20.559-900 Rio de Janeiro (Brazil); Lopes, R.T., E-mail: ricardo@lin.ufrj.br [Nuclear Instrumentation Laboratory, COPPE/UFRJ, P.O. Box 68509, 21.941-972 Rio de Janeiro (Brazil)

    2012-07-15

    In this work we analyzed serum samples from patients with Sickle Cell Anemia (SCA) using Total Reflection X-Ray Fluorescence using Synchrotron Radiation (SRTXRF). The SRTXRF measurements were performed at the X-Ray Fluorescence Beamline at the Brazilian National Synchrotron Light Laboratory (LNLS). We studied forty-three patients aged 18-50 suffering from SCA and sixty healthy volunteers aged 18-60. It was possible to determine the concentrations of the following elements: P, S, Cl, K, Ca, Fe, Cu, Zn, Br and Rb. Moreover, there are evidences of an association among Fe, Cu, Zn and Cu/Zn in the SCA pathogenesis process. The concentrations of Fe and Cu in the serum samples of patients with SCA were larger, 120% and 20%, respectively, when compared with the CG. The serum level Cu/Zn ratio was significantly higher (60%) in the serum samples from patients suffering from SCA than from the CG. Therefore, the Cu/Zn ratio can be used as an adjuvant index in enhancement for diagnosis of SCA. - Highlights: Black-Right-Pointing-Pointer Serum samples from patients with Sickle Cell Anemia (SCA) were analyzed by SRTXRF. Black-Right-Pointing-Pointer It was possible to determine the concentrations of the P, S, Cl, K, Ca, Fe, Cu, Zn, Br and Rb. Black-Right-Pointing-Pointer There are evidences of an association among Fe, Cu, Zn and Cu/Zn in the SCA process. Black-Right-Pointing-Pointer The results indicate that the Cu/Zn ratio can be used as an adjuvant index for diagnosis of SCA.

  10. Development of Sintered Iron Driving Bands

    R. P. Khanna

    1974-07-01

    Full Text Available The present investigation reports some detailed studies carried out on the development testing and proving of sintered Iron Driving Bands. Sintering studies on two different types of iron powders together with a few Fe-Cu compositions have been made and based on the results there of, parameters for development iron driving bands have been standardised. The results obtained clearly demonstrate that substitution of copper by sintered iron is highly practicable alternative.

  11. Fe and Co nanostructures embedded into the Cu(100) surface: Self-Organization and magnetic properties

    The self-organization and magnetic properties of small iron and cobalt nanostructures embedded into the first layer of a Cu(100) surface are investigated using the self-learning kinetic Monte Carlo method and density functional theory. The similarities and differences between the Fe/Cu(100) and the Co/Cu(100) are underlined. The time evolution of magnetic properties of a copper monolayer with embedded magnetic atoms at 380 K is discussed

  12. Milk and Dairy Products : A Unique Micronutrient Combination

    2011-01-01

    Milk and dairy products contain micronutrients such as minerals and vitamins, which contribute to multiple and different vital functions in the organism. The mineral fraction is composed of macroelements (Ca, Mg, Na, K, P, and Cl) and oligoelements (Fe, Cu, Zn, and Se). From a physicochemical point of view, the chemical forms, the associations with other ions or organic molecules, and the location of macroelements such as Ca, Mg, Na, K, P, and Cl in milk are relatively well described and unde...

  13. Measurement of the pollutants on the surface of crystal slice using PIXE

    Zhu Guang Hua; Wang Xin Fu; Zhou Hong Yu

    2001-01-01

    The analytical sensitivity and detection limit and the applications of the PIXE technique or the samples of crystal slice are presented. The crystal slices implanted with oxygen ions at different implantation machines are polluted with element Cr, Mn, Fe, Cu etc. during oxygen ion implantation. These results show that PIXE method has high sensitivity and is non-destructive for measuring pollutants, and is suitable in this research field

  14. Trace elements analysis by PIXE (particle induced x-ray excitation) and AAS (atomic absorption spectrometry) from environmental samples

    The aim of this work is the micro elemental analysis of environmental samples by PIXE (Particle Induced X-ray Excitation) method and AAS (Atomic Absrobtion Spectrometry). The samples were collected from neighborhood of Targoviste city (mulberry, apple, poplar, walnut, prune, maple). The concentration data have been obtain for the elements: S, Cl, K, Ca, Ti, Cr, Mn, Fe, Co, Ni, Cu, Zn, As, Br, Sr by PIXE method and Mn, Fe, Cu, Cr, Se, Zn by AAS method. A good correlation b

  15. Fe and Co nanostructures embedded into the Cu(100) surface: Self-Organization and magnetic properties

    Kolesnikov, S. V., E-mail: kolesnikov@physics.msu.ru; Klavsyuk, A. L.; Saletsky, A. M. [Moscow State University, Faculty of Physics (Russian Federation)

    2015-10-15

    The self-organization and magnetic properties of small iron and cobalt nanostructures embedded into the first layer of a Cu(100) surface are investigated using the self-learning kinetic Monte Carlo method and density functional theory. The similarities and differences between the Fe/Cu(100) and the Co/Cu(100) are underlined. The time evolution of magnetic properties of a copper monolayer with embedded magnetic atoms at 380 K is discussed.

  16. Biochemical Studies in Some Indigenous Dye Yielding Plants of Manipur

    Joylani D. SAIKHOM; Jekendra S. SALAM; Kumar S. POTSHANGBAM; Manabendra D. Choudhury; Haripriya D. MAIBAM

    2013-01-01

    Ten natural dye yielding and two mordant plants were biochemically analyzed. Though natural dyes are widely used, information about the active principles responsible for dyeing is hardly available. In the present experiment, total chlorophyll, carotinoids, tannins, phenolics, flavonoids and curcumin were determined among the dye yielding plants, while K, S, P, Ca, Mg, Mn, Zn, Fe, Cu and Co were determined in the case of mordant plants. In Bixa orellana, used for yellow dyeing, the carotinoid ...

  17. Advancements in Development of Chemical-Looping Combustion: A Review

    He Fang; Li Haibin; Zhao Zengli

    2009-01-01

    Chemical-looping combustion (CLC) is a novel combustion technology with inherent separation of greenhouse CO2. Extensive research has been performed on CLC in the last decade with respect to oxygen carrier development, reaction kinetics, reactor design, system efficiencies, and prototype testing. Transition metal oxides, such as Ni, Fe, Cu, and Mn oxides, were reported as reactive species in the oxygen carrier particles. Ni-based oxygen carriers exhibited the best reactivity and stability dur...

  18. Magnetostriction Dependence of the Relaxation Frequency in the Magnetoimpedance Effect for Amorphous and Nanocrystalline Ribbons

    M.L.Sánchez; V.M.Prida; B.Hernando; G.V.Kurlyandskaya; J.D.Santos; M.Tejedor; M.Vázquez

    2002-01-01

    The magnetoimpedance effect and changes of the relaxation frequency fx are studied in CoFeSiB and CoFeMoSiB amorphous and FeCuNbSiB nanocrystalline ribbons. The evolution of the magnetostriction constant λs and relaxation frequency is analysed for the states with different magnetic anisotropies induced in the same ribbons.A monotonic decrease of the relaxation frequency is observed for shifting of λs towards positive values.

  19. Geochemistry of polymetallic nodules from the Central Indian Ocean basin

    Valsangkar, A.B.; Khadge, N.H.; Desa, J.A.E.

    ; \\[\\] > l0 cm. Pacific Ocean; A nodules; x sediments. Average shale values from Piper (1974). POLYMETALLIC NODULES FROM THE CENTRAL INDIAN OCEAN BASIN TABLE 3A Inter-element relationship in the CIOB nodules Moisture Mn Fe Cu Ni Co Cu + Ni + Co Moisture...-242. Lyle, M., 1982. Estimating growth rates of ferromanganese nodules from chemical composition: implications for nodule formation processes. Geochim. Cosmochem. Acta., 46: 2301- 2306. Piper, D.Z., 1974. Rare earth elements and the sedimentary cycle: A...

  20. A study of the hard magnetic properties in different hard magnetic materials

    The magnetic properties of several hard magnetic materials have been investigated to determine any trends in their magnetic characteristics. The materials studied were Nd15Fe77B8, SmCo5, Sm2 (Co,Fe,Cu,Zr)17, strontium ferrite magnets and single domain particles of Ba-ferrite and Cu-Mn-Al. The initial magnetization curves, field dependence of coercivity and remanence curves were measured

  1. Biomarkers of environmental contaminants in field population of green mussel (Perna viridis) from Karnataka-Kerala coast (South West coast of India).

    Krishnakumar, P.K.; Sasikumar, Geetha; Bhat, G. S.; Asokan, D.P.K.

    2006-01-01

    Biomarker: sister chromatid exchange (SCE); chromosomal aberration; micronucleus (MN); hemic neoplasia (HN), mutagenic activity; comet cells. Exposure/effect represented: exposure to trace metals (Fe, Cu, Ni, Cd, Cr, Zn, Pb, Mn) / DNA damage. Analytical technique: Toxic and essential elements in tissues were determined using AAS; metaphase chromosomes were viewed using light microscope (Olympus BX50) with image analysis facility; hemolymph was stained using the Schiff Feulgen-picromethyl blu...

  2. Bioaccumulation of selected heavy metals by the water fern, Azolla filiculoides Lam. in a wetland ecosystem affected by sewage, mine and industrial pollution

    Wet, L.P.D. de; Schoonbee, H.J.; Pretorius, J.; Bezuidenhout, L.M. (Rand Afrikaans University, Johannesburg (South Africa). Depts. of Zoology and Botany, Research Unit for Aquatic and Terrestrial Ecosystems)

    1990-10-01

    The bio-accumulation of the heavy metals, Fe, Cu, Ni, Pb, Zn, Mn and Cr by the water fern, Azolla filiculoides Lam. in a wetland ecosystem polluted by effluents from sewage works, mines and industries was investigated. Results showed that the different metals can be accumulated by the water fern at concentration levels not necessarily related to their actual concentrations in the aquatic environment, as measured in this case, in the bottom sediments. 45 refs., 1 fig., 3 tabs.

  3. Determination of Heavy Metals in Roach (Rutilus rutilus) and Bleak (Alburnus alburnus) in Zhrebchevo Dam Lake

    Georgi I. Zhelyazkov; Dian M. Georgiev; Lilko K. Dospatliev; Yordan S. Staykov

    2014-01-01

    The aim of this study was to examine the concentration of iron (Fe), nickel (Ni), lead (Pb), manganese (Mn), copper (Cu), chromium (Cr), cadmium (Cd) and zinc (Zn) in roach (Rutilus rutilus) and bleak (Alburnus alburnus) as species for human consummation. Two fresh water fish species, roach and bleak were caught from Zhrebchevo Dam Lake in Bulgaria. Determination of heavy metals (Fe, Cu, Ni, Pb, Zn, Mn, Cr and Cd) in muscle samples were performed with electrothermal atomic absorption spec...

  4. Interface magnetism of 3d transition metals

    Niklasson, A. M. N.; Johansson, B.; Skriver, Hans Lomholt

    1999-01-01

    The layered resolved magnetic spin moments of the magnetic 3d bilayer interfaces Fe/V bcc, Fe/Co bcc, Fe/Cu bcc, Co/V bcc, Co/Ni fee, Co/Cu fee, Ni/V fee, Ni/Cr fcc, Ni/Cu fee and the magnetic surfaces Fe bcc, Co bcc, Co fee, and Ni fee are calculated for the (001), (011), and (111) orientations by...

  5. Determination of Cu/Zn and Fe in human serum of patients with sickle cell anemia using radiation synchrotron

    In this work we analyzed serum samples from patients with Sickle Cell Anemia (SCA) using Total Reflection X-Ray Fluorescence using Synchrotron Radiation (SRTXRF). The SRTXRF measurements were performed at the X-Ray Fluorescence Beamline at the Brazilian National Synchrotron Light Laboratory (LNLS). We studied forty-three patients aged 18–50 suffering from SCA and sixty healthy volunteers aged 18–60. It was possible to determine the concentrations of the following elements: P, S, Cl, K, Ca, Fe, Cu, Zn, Br and Rb. Moreover, there are evidences of an association among Fe, Cu, Zn and Cu/Zn in the SCA pathogenesis process. The concentrations of Fe and Cu in the serum samples of patients with SCA were larger, 120% and 20%, respectively, when compared with the CG. The serum level Cu/Zn ratio was significantly higher (60%) in the serum samples from patients suffering from SCA than from the CG. Therefore, the Cu/Zn ratio can be used as an adjuvant index in enhancement for diagnosis of SCA. - Highlights: ► Serum samples from patients with Sickle Cell Anemia (SCA) were analyzed by SRTXRF. ► It was possible to determine the concentrations of the P, S, Cl, K, Ca, Fe, Cu, Zn, Br and Rb. ► There are evidences of an association among Fe, Cu, Zn and Cu/Zn in the SCA process. ► The results indicate that the Cu/Zn ratio can be used as an adjuvant index for diagnosis of SCA.

  6. Effects of aging time and temperature of Fe-1wt.%Cu on magnetic Barkhausen noise and FORC

    Muad Saleh

    2016-05-01

    Full Text Available Magnetic Barkhausen noise (MBN, hysteresis measurements, first order reversal curves (FORC, Vickers microhardness, and Transmission Electron Microscopy (TEM analyses were performed on Fe-1wt.%Cu (Fe-Cu samples isothermally aged at 700°C for 0.5 – 25 hours to obtain samples with different sized Cu precipitates and dislocation structures. Fe-Cu is used to simulate the thermal and irradiation-induced defects in copper-containing nuclear reactor materials such as cooling system pipes and pressure vessel materials. The sample series showed an initial increase followed by a decrease in hardness and coercivity with aging time, which is explained by Cu precipitates formation and growth as observed by TEM measurements. Further, the MBN envelope showed a continuous decrease in its magnitude and the appearance of a second peak with aging. Also, FORC diagrams showed multiple peaks whose intensity and location changed for different aging time. The changes in FORC diagrams are attributed to combined changes of the magnetic behavior due to Cu precipitate characteristics and dislocation structure. A second series of samples aged at 850°C, which is above the solid solution temperature of Fe-Cu, was studied to isolate the effects of dislocations. These samples showed a continuous decrease in MBN amplitude with aging time although the coercivity and hardness did not change significantly. The decrease of MBN amplitude and the appearance of the second MBN envelope peak are attributed to the changes in dislocation density and structure. This study shows that the effect of dislocations on MBN and FORC of Fe-Cu materials can vary significantly and should be considered in interpreting magnetic signatures.

  7. Effects of aging time and temperature of Fe-1wt.%Cu on magnetic Barkhausen noise and FORC

    Saleh, Muad; Cao, Yue; Edwards, Danny J.; Ramuhalli, Pradeep; Johnson, Bradley R.; McCloy, John S.

    2016-05-01

    Magnetic Barkhausen noise (MBN), hysteresis measurements, first order reversal curves (FORC), Vickers microhardness, and Transmission Electron Microscopy (TEM) analyses were performed on Fe-1wt.%Cu (Fe-Cu) samples isothermally aged at 700°C for 0.5 - 25 hours to obtain samples with different sized Cu precipitates and dislocation structures. Fe-Cu is used to simulate the thermal and irradiation-induced defects in copper-containing nuclear reactor materials such as cooling system pipes and pressure vessel materials. The sample series showed an initial increase followed by a decrease in hardness and coercivity with aging time, which is explained by Cu precipitates formation and growth as observed by TEM measurements. Further, the MBN envelope showed a continuous decrease in its magnitude and the appearance of a second peak with aging. Also, FORC diagrams showed multiple peaks whose intensity and location changed for different aging time. The changes in FORC diagrams are attributed to combined changes of the magnetic behavior due to Cu precipitate characteristics and dislocation structure. A second series of samples aged at 850°C, which is above the solid solution temperature of Fe-Cu, was studied to isolate the effects of dislocations. These samples showed a continuous decrease in MBN amplitude with aging time although the coercivity and hardness did not change significantly. The decrease of MBN amplitude and the appearance of the second MBN envelope peak are attributed to the changes in dislocation density and structure. This study shows that the effect of dislocations on MBN and FORC of Fe-Cu materials can vary significantly and should be considered in interpreting magnetic signatures.

  8. Examination of the trace element content of beetroot by X-ray fluorescence analysis

    The paper deals with the determination of Mn, Fe, Cu, Zn, Br, Rb, Sr, Mo concentration in beetroot by energy dispersive X-ray fluorescence method. The exciting source was 125I with 555 MBq activity. For the analysis Si(Li) semiconductor detectors were applied and for the data processing a minicomputer (type HP 9825 A) was used. Results are given in tabulated form. (Sz.J.)

  9. Study of the precipitation and of the hardening microscopic mechanisms under irradiation in dilute ferritic alloys

    The copper precipitation plays a significant role in the embrittlement process of reactor vessel steels under neutron irradiation at 300 deg C. In order to understand the copper precipitation mechanisms, we have studied model ferritic binary FeCu and ternary alloys FeCuX (X=Mn,Ni, Cr, P). These materials have been either Irradiated with 2.5 MeV electrons In the 175-360 deg C temperature range or thermal aged at 500 deg C. The evolution of materials has been followed by resistivity measurements under irradiation, by small angle neutron scattering and by Vickers microhardness measurements. We have shown the similarity of copper precipitation under thermally ageing at 500 deg C and electron Irradiation at 300 deg C, in FeCu1,34%. This result confirms that the main effect of electronic irradiation is to accelerate precipitation. Nevertheless, we have observed that irradiation induces an additional contribution to hardening attributed to point defect clusters. Concerning the ternary alloys, we observed that at 300 deg C the addition of a third element has no significant effect on the copper precipitation kinetic under irradiation but that at lower temperature manganese slows down precipitation kinetic. In order to reproduce the experimental results obtained on FeCu1,34% by using a cluster kinetics model, we have to suppose that the precipitation is heterogeneous and controlled by interface reactions for the small size clusters. In addition, neutron or electron irradiated industrial steels have been studied by small angle neutron scattering. The results revealed the presence of nano-metric solute clusters which contain few copper atoms and which are not linked to the formation of displacement cascades. (author)

  10. The application of energy-dispersive x-ray fluorescence spectrometry (EDXRF) to the analysis of cosmetic evidence in Indian nail polishes

    The application of energy-dispersive x-ray fluorescence (EDXRF) spectrometry in the quantitative analysis of samples of Indian nail polishes of apparently similar shades from different manufacturers has been examined by evaluating the possibility of detecting spurious material which is marketed under the guise of a popular brand. On the basis of the number of elements detected, and from the ratios of particular elements [Fe/Ti,Fe/Cu,Ti/Cu] the results are very encouraging. (author)