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Sample records for 111-5 magnetic separator

  1. Calibración del separador magnético de alta intensidad magnet-lift mlh (13) 111-5 para su uso en el laboratorio de termocronología de la UCV

    Scientific Electronic Library Online (English)

    A, MAURICIO; CELLA, BERMÚDEZ; RAQUEL C, ANAYA.

    Full Text Available En este artículo se presenta la calibración del separador magnético de alta intensidad Magnet-lift MLH (13) 111-5 existente en el Laboratorio de Termocronología de la Universidad Central de Venezuela con la finalidad de separar magnéticamente minerales pertenecientes a areniscas y muestras granítica [...] s para su posterior fechado por el método de huellas de fisión. Los resultados obtenidos de esta calibración fueron aplicados a una muestra de 10 kilogramos pertenecientes a unaconcentración inicial de minerales de la Formación Betijoque del flanco norte de Los Andes Venezolanos. Se concluye que el Magnet-lift presenta amplias ventajas con respecto a los separadores magnéticos convencionales y además optimiza el tiempo de procesamiento de rocas detríticas que posteriormente serán fechadas por el método de datación empleado eneste laboratorio con el fin de discriminar la edad del último evento tecto-térmico ocurrido en la zona de estudio. Abstract in english In this article we present the calibration of a high intensity Magnet-lift MLH (13) 111-5 magnetic separator located in the Thermochronology Laboratory of the Universidad Central de Venezuela with the purpose of magnetically separating minerals of sandstone and granite samples to be subsequently sub [...] jected to the fission track dating method (FTDM). The results of this calibration were applied to 10 kilogram sample belonging to an initial concentration of minerals of Betijoque´s Formation on the north flank of Venezuelans Andes. We conclude that the Magnet-lift presents a number of advantages with regard to conventional magnetic separators as well as optimizing the preparation time of detritic rocks for their dating by the fission track method.

  2. High gradient magnetic separation

    International Nuclear Information System (INIS)

    In a process in which magnetic material is trapped in a filter disposed in a magnetic field, and is unloaded by passing a fluid through the filter in the absence of the initial magnetic field, the magnetic field is first reduced to an intermediate value to allow unloading of the more weakly magnetic particles, the more strongly magnetic particles being retained and subsequently unloaded by further reduction of the magnetic field. Stage by stage reduction of the magnetic field during unloading allows separation of different species from the mixture. As an example the method can be applied to the separation of uranium compounds from mine ores. The uranium compounds are magnetic, while most of the other constituents of the ore are non-magnetic. The starting material is a suspension of the ore. Water is used for unloading. The filter material in this case is stainless steel balls. (author)

  3. USE OF SUPERCONDUCTING MAGNETS IN MAGNETIC SEPARATION

    OpenAIRE

    Parker, M.

    1984-01-01

    A review is given assessing the potential for superconducting high-field magnet systems in magnetic separation. Particular attention is given to the advantages of the reciprocating canister approach to high gradient magnetic separation and to the use of quadrupole magnets in open gradient magnetic separation.

  4. Magnetic separation techniques and HTS magnets

    International Nuclear Information System (INIS)

    Magnetic separation techniques have been widely used, and the separation efficiency is related to the strength of the magnetic field applied and the field gradient to trap the magnetic particles. Conventional low-Tc superconducting wire has been used to increase the field and to reduce normal electromagnetic winding resistive loss, and now the Bi-2223/Ag HTS wire provides a new opportunity for higher magnetic field and efficiency for use in a high-gradient magnetic separator as the magnetic field winding. Magnetic separation techniques are reviewed with regard to their magnetic fields, and the magnetic field winding required for this application is analysed with the consideration of using the HTS wire. (author)

  5. Magnetic separation in microfluidic systems

    DEFF Research Database (Denmark)

    Smistrup, Kristian

    2007-01-01

    This Ph.D. thesis presents theory, modeling, design, fabrication, experiments and results for microfluidic magnetic separators. A model for magnetic bead movement in a microfluidic channel is presented, and the limits of the model are discussed. The effective magnetic field gradient is defined, and it is argued that it is a good measure, when comparing the performance of magnetic bead separators. It is described how numeric modelling is used to aid the design of microfluidic magnetic separation systems. An example of a design optimization study is given. A robust fabrication scheme has been developed for fabrication of silicon based systems. This fabrication scheme is explained, and it is shown how, it is applied with variations for several designs of magnetic separators. An experimental setup for magnetic separation experiments has been developed. It has been coupled with an image analysis program to facilitate real-time monitoring of the experiments. The set-up and experimental protocol are described in detail. Results are presented for ’active’ magnetic bead separators, where on-chip microfabricated electromagnets supply the magnetic field and field gradients necessary for magnetic bead separation. It is shown conceptually how such a system can be applied for parallel biochemical processing in a microfluidic system. ’Passive’ magnetic separators are presented, where on-chip soft magnetic elements are magnetized by an external magnetic field and create strong magnetic fields and gradients inside a microfluidic channel. Systems with the elements placed beside the microfluidic channel is combined with hydrodynamic focusing to demonstrate a magnetic bead microarray inside a microfluidic channel. Systems where the on-chip magnetic material is placed underneath the microfluidic channel are also presented. One of these designs feature multiple magnetic length scales, and it is shown that this enhances bead capture ability. A ’hybrid’ magnetic separator design, where the magnetic field from on-chip current lines couples with an externally applied homogenous field to create strong fields and gradients is demonstrated. This gives extra magnetic bead manipulation possibilities compared to the passive designs. It is demonstrated how this can be used for magnetic bead microarrays. Finally, it is discussed, based on the research presented in this thesis, how to further develop magnetic separation systems in microfluidic systems, and recommendations are given for the choice of magnetic design based on the desired application.

  6. Magnetic separation in microfluidic systems

    OpenAIRE

    Smistrup, Kristian; Hansen, Mikkel Fougt; Bruus, Henrik; Tang, Peter Torben; Kruhne, Ulrich Willi Walter

    2007-01-01

    This Ph.D. thesis presents theory, modeling, design, fabrication, experiments and results for microfluidic magnetic separators. A model for magnetic bead movement in a microfluidic channel is presented, and the limits of the model are discussed. The effective magnetic field gradient is defined, and it is argued that it is a good measure, when comparing the performance of magnetic bead separators. It is described how numeric modelling is used to aid the design of microfluidic...

  7. Superconducting high gradient magnet separator

    International Nuclear Information System (INIS)

    The experimental studies of a superconducting high gradient magnetic separator have been made to examine the applicability. The factors which affect the efficiency of separation were checked such as shape of the filter cross section, diameter, diameter of separated particles, susceptibility, external field and so on. To make use of the different separation efficiency on different conditions, it is possible to separate particles according to the size and susceptibility. The applicability of superconducting high gradient magnetic separator is discussed based on the experimental data

  8. Environmental remediation using magnetic separation

    International Nuclear Information System (INIS)

    High Gradient Magnetic Separation (HGMS) is a physical separation process that can be used to segragate materials in a mixture on the basis of magnetic susceptibility. Unlike ferromagnetic separation methods, HGMS is generally used to separate paramagnetic (slightly magnetic) materials from diamagnetic materials. Soils consist primarily of diamagnetic components. Because all uranium and plutonium compounds are paramagnetic, HGMS can be used to extract uranium and plutonium from soils. Applications of HGMS usually involves passing a slurry of the contaminated mixture through a magnetized volume. The magnetized volume is filled with a porous magnetic matrix material, such as steel wool or expanded nickel, to generate high field gradients in the magnetized working volume. Ferromagnetic and paramagnetic components of the mixture and captured on the matrix. Thus, most of the soil slurry is decontaminated and can be returned to the local environment. Preliminary results at Los Alamos with nonradiative surrogate materials show over 99% extraction of the paramagnetic components

  9. Magnetic separation for soil decontamination

    International Nuclear Information System (INIS)

    High gradient magnetic separation (HGMS) is a physical separation process that is used to extract magnetic particles from mixtures. The technology is used on a large scale in the kaolin clay industry to whiten or brighten kaolin clay and increase its value. Because all uranium and plutonium compounds are slightly magnetic, HGMS can be used to separate these contaminants from non-magnetic soils. A Cooperative Research and Development Agreement (CRADA) was signed in 1992 between Los Alamos National Laboratory (LANL) and Lockheed Environmental Systems and Technologies Company (LESAT) to develop HGMS for soil decontamination. This paper reports progress and describes the HGMS technology

  10. Feasibility study on magnetic separation

    International Nuclear Information System (INIS)

    From the viewpoint of applicability survey on the magnetic separation using super-conducting magnet in the nuclear fuel cycle system, a basic study has been made to clarify separation characteristics of magnetic chromatography (MC). We developed a computer simulation code to make clear the separation mechanism, and pursued basic experiments to demonstrate magnetic force acting on weakly magnetized fine particles. As a result, with our successfully developed simulator we can accurately simulate the transient behavior of fine particles undergoing both convection (due to fluid flow and magnetic forces) and diffusion. It is also shown that separation can successfully be done on Nd and hypothetical radioactive particles with diameters of several ten nanometers. In our experiments, we could confirm the high intensity and high gradient magnetic field effect of delaying the flow velocity of Nd colloidal particles in an MC column. MC technology will contribute to nuclear fuel cycle systems as an analysis technology of secondary waste free after the next step of R and D is completed for practical application in the future. (author)

  11. Magnetic separation of uranium

    International Nuclear Information System (INIS)

    Method for recovering uranium from a calcium fluoride aqueous slurry which contains less than 100 parts per million of iron. The slurry is passed through a high gradient magnetic seperator which results in the detention of the uranium on the intermediate in the seperator. The uranium is then removed from the intermediate by, for example, dissolution in a carbonate solution or a nitric acid solution. Uranium in the carbonate solution can then be removed with an ion exchange column and later removed from the ion exchange column with a nitric acid solution. Uranium in the nitric acid solution can be extracted using a DEPA-TOPO extractant

  12. Magnetic separation for environmental remediation

    International Nuclear Information System (INIS)

    High Gradient Magnetic Separation (HGMS) is a form of magnetic separation used to separate solids from other solids, liquids or gases. HGMS uses large magnetic field gradients to separate ferromagnetic and paramagnetic particles from diamagnetic host materials. The technology relies only on physical properties, and therefore separations can be achieved while producing a minimum of secondary waste. Actinide and fission product wastes within the DOE weapons complex pose challenging problems for environmental remediation. Because the majority of actinide complexes and many fission products are paramagnetic, while most host materials are diamagnetic, HGMS can be used to concentrate the contaminants into a low volume waste stream. The authors are currently developing HGMS for applications to soil decontamination, liquid waste treatment, underground storage tank waste treatment, and actinide chemical processing residue concentration. Application of HGMS usually involves passing a slurry of the contaminated mixture through a magnetized volume. Field gradients are produced in the magnetized volume by a ferromagnetic matrix material, such as steel wool, expanded metal, iron shot, or nickel foam. The matrix fibers become trapping sites for ferromagnetic and paramagnetic particles in the host material. The particles with a positive susceptibility are attracted toward an increasing magnetic field gradient and can be extracted from diamagnetic particles, which react in the opposite direction, moving away from the areas of high field gradients. The extracted paramagnetic contaminants are flushed from the matrix fibers when the magnetic field is reduced to zero or when the matrix canister is removed from the magnetic field. Results are discussed for the removal of uranium trioxide from water, PuO2, U, and Pu from various soils (Fernald, Nevada Test Site), and the waste water treatment of Pu and Am isotopes using HGMS

  13. Separation of magnetic field lines

    International Nuclear Information System (INIS)

    The field lines of magnetic fields that depend on three spatial coordinates are shown to have a fundamentally different behavior from those that depend on two coordinates. Unlike two-coordinate cases, a flux tube in a magnetic field that depends on all three spatial coordinates that has a circular cross section at one location along the tube characteristically has a highly distorted cross section at other locations. In an ideal evolution of a magnetic field, the current densities typically increase. Crudely stated, if the current densities increase by a factor ?, the ratio of the long to the short distance across a cross section of a flux tube characteristically increases by e2?, and the ratio of the longer distance to the initial radius increases as e?. Electron inertia prevents a plasma from isolating two magnetic field structures on a distance scale shorter than c/?pe, which is about 10 cm in the solar corona, and reconnection must be triggered if ? becomes sufficiently large. The radius of the sun, R?=7×1010cm is about e23 times larger, so when ??23, two lines separated by c/?pe at one location can be separated by the full scale of any magnetic structures in the corona at another. The conditions for achieving a large exponentiation, ?, are derived, and the importance of exponentiation is discussed.

  14. Magnetic Enhancement in High Gradient Magnetic Separation.

    Science.gov (United States)

    Kelland, David Ross

    Available from UMI in association with The British Library. Requires signed TDF. An effective way to improve the performance of High Gradient Magnetic Separation (HGMS) is to increase the magnetization of small particulates. An example in which this can be demonstrated is in the use of HGMS to desulfurize coal. Part of the sulfur in coal occurs as finely divided pyrite. Is removal before combustion would reduce SO_2 emission with a subsequent reduction in acid rain. Experiments on direct heating of mineral pyrite achieved enhanced pyrite magnetization in several different atmospheres; this increase in magnetization was measured on a vibrating sample magnetometer. Mossbauer and electron microprobe analysis have identified the converted mineral as ferrimagnetic monoclinic pyrrhotite along with iron oxides and even iron. Selective heating of the pyrite in coal. To save energy by not heating the coal itself, was accomplished by employing high power density microwave irradiation. Thermal reflectance measurements clearly showed that the final temperature reached in the heated pyrite was higher than that in the coal. Then the improvement in HGMS separations of the partially converted pyrite from coals was demonstrated in samples irradiated at a frequency of 2.45 gigahertz and 5.4 kW of power. Pyrite removal was improved as much as 30-40% (at constant heating value recovery) over that with HGMS alone. In addition to this improvement in HGMS performance, the work provides a microscopic insight into the process of magnetic conversion.

  15. Method of magnetic separation and apparatus therefore

    Science.gov (United States)

    Oder, Robin R. (Inventor)

    1991-01-01

    An apparatus for magnetically separating and collecting particulate matter fractions of a raw sample according to relative magnetic susceptibilities of each fraction so collected is disclosed. The separation apparatus includes a splitter which is used in conjunction with a magnetic separator for achieving the desired fractionation.

  16. Magnetic Separator Enhances Treatment Possibilities

    Science.gov (United States)

    2008-01-01

    Since the earliest missions in space, NASA specialists have performed experiments in low gravity. Protein crystal growth, cell and tissue cultures, and separation technologies such as electrophoresis and magnetophoresis have been studied on Apollo 14, Apollo 16, STS-107, and many other missions. Electrophoresis and magnetophoresis, respectively, are processes that separate substances based on the electrical charge and magnetic field of a molecule or particle. Electrophoresis has been studied on over a dozen space shuttle flights, leading to developments in electrokinetics, which analyzes the effects of electric fields on mass transport (atoms, molecules, and particles) in fluids. Further studies in microgravity will continue to improve these techniques, which researchers use to extract cells for various medical treatments and research.

  17. Superconducting discs as permanent magnets for magnetic separation

    International Nuclear Information System (INIS)

    Magnetic separation is used widely in the mineral processing industry to concentrate and recover valuable minerals. Superconducting discs offer the opportunity to produce stronger magnetic forces than are available from conventional permanent magnets. Permanent magnets have been used to provide fields and field gr[ients for drum separators in which magnetic forces are used to hold magnetisable mineral particles against the surface of a rotating drum against gravity in such a way that they are spatially separated from less magnetisable particles and for 'open gr[ient' separators in which the particles are separated, by deflection with magnetic forces, from a falling stream of mixed particles, the 'falling curtain' technique or by guiding them on a belt moving over a magnetized rotor. Calculations of the field distribution within superconducting discs by the authors have provided a basis for the examination of their use in magnetic separation. A number of configurations of discs are discussed in relation to magnetic separator performance. (orig.)

  18. Superconducting magnetic separators for the mineral industry

    International Nuclear Information System (INIS)

    Superconducting magnets present the possibility of generating magnetic fields considerably beyond those possible by conventional magnets, but in order to take advantage of this, new designs of magnetic separators are required. Designs suitable for the treatment of wet and dry materials are described. Two experimental separators, one for wet materials and the other for dry, have been tested in South Africa. The experience gained has enabled an assessment to be made of the requirements for an S.C.M.S. for the treatment of uranium ores, and these are incorporated in a new separator being constructed. Some general principles in the design of magnetic separators are outlined, and the qualitative principles as applied to wet and dry magnetic separation by means of S.C.M.S. are discussed in detail. The difference in the design requirements for wet and dry separation by superconducting magnets is explained. The importance of the proportion of magnetic material in the feed is discussed, and it is shown that, especially in dry separation, several stages of treatment are desirable in the feed contains a large proportion of magnetic material. The axial introduction of the feed in the dry magnetic-separation process presents interesting problems that have been carefully studied and are discussed in detail in the paper. An appreciation of the design principles discussed will contribute to the development of economically attractive magnetic separators for the mineral industryseparators for the mineral industry

  19. Magnetic separation of antibiotics by electrochemical magnetic seeding

    Energy Technology Data Exchange (ETDEWEB)

    Ihara, I; Toyoda, K [Department of Agricultural Engineering and Socio Economics, Kobe University, Nada, Kobe 657-8501 (Japan); Beneragama, N; Umetsu, K [Department of Animal Science, Obihiro University of Agriculture and Veterinary Medicine, Obihiro, Hokkaido 080-8555 (Japan)], E-mail: ihara@port.kobe-u.ac.jp

    2009-03-01

    Magnetic separation of several classes of antibiotics was investigated using electrochemical magnetic seeding. Electrocoagulation with a sacrificial anode followed by addition of magnetite particles was applied for the magnetic seeding of antibiotics. With electrochemical magnetic seeding using an iron anode, tetracycline antibiotics (oxytetracycline, chlortetracycline, doxycycline and tetracycline) and cephalosporin antibiotic (cefdinir) were rapidly removed from synthetic wastewater by magnetic separation using a neodymium magnet. Iron and aluminium anodes were suitable for magnetic seeding of the antibiotics. The results indicated that the ability of antibiotics to form strong complex with iron and aluminium allowed the higher removal by magnetic separation. This method would be appropriate for rapid treatment of antibiotics in wastewater.

  20. Magnetic separation of antibiotics by electrochemical magnetic seeding

    International Nuclear Information System (INIS)

    Magnetic separation of several classes of antibiotics was investigated using electrochemical magnetic seeding. Electrocoagulation with a sacrificial anode followed by addition of magnetite particles was applied for the magnetic seeding of antibiotics. With electrochemical magnetic seeding using an iron anode, tetracycline antibiotics (oxytetracycline, chlortetracycline, doxycycline and tetracycline) and cephalosporin antibiotic (cefdinir) were rapidly removed from synthetic wastewater by magnetic separation using a neodymium magnet. Iron and aluminium anodes were suitable for magnetic seeding of the antibiotics. The results indicated that the ability of antibiotics to form strong complex with iron and aluminium allowed the higher removal by magnetic separation. This method would be appropriate for rapid treatment of antibiotics in wastewater.

  1. Separation characteristics of open gradient magnetic separation using high-temperature superconducting magnet

    International Nuclear Information System (INIS)

    An open gradient magnetic separator using solenoid magnet was proposed. Simulation study was performed to investigate the basic separation characteristics of our separation method by analyzing the dynamic motion of magnetic particles. The simulation results show that the separation of ferromagnetic particles of several tens micrometer diameter is enough feasible. Separation experiment using a high-temperature superconducting magnet was performed to verify the validity of our method

  2. Magnet design for superconducting open gradient magnetic separator

    International Nuclear Information System (INIS)

    The use of superconductivity opens new applications for magnetic separation because very high magnetic fields become available. In this paper the magnet design for a laboratory scale superconducting open gradient magnetic separator is presented. The separator will be used to optimize the separation parameters for different kinds of applications, such as the foundry sand purification. Therefore, the goal of the magnet design is to obtain a constant magnetic force density distribution inside the working volume. The high magnitude of magnetic force density is required because the materials to be separated have low magnetic susceptibilities. The maximum achievable force density is determined by the critical current in superconducting magnets. The advantages and drawbacks of solenoid, racetrack and saddle coil geometries are compared. Ways for improving the performance of the system is discussed. Finally, the influence of the stray field on the slurry flow outside the working volume is studied

  3. Superconductor high gradient magnetic separator

    International Nuclear Information System (INIS)

    This patent describes a high gradient superconductor magnet separator comprising, a hollow cylindrical enclosure made of ferrous material and having an axially disposed flow passage therethrough, a toroidal shaped vacuum vessel in the cylindrical enclosure, a toroidal shaped liquid nitrogen vessel in the vacuum vessel, and a toroidal shaped liquid helium vessel in the vacuum vessel. The toroidal shaped liquid helium vessel is disposed concentrically to and above the liquid nitrogen vessel and spaced therefrom. A coil made of superconducting material is in the liquid helium vessel, and an inner coil support ring is in the vacuum vessel and concentric to the flow passage. The inner coil support ring has a lower end supported on the vacuum vessel and an upper end engaging the vacuum vessel. An outer coil support ring has an upper end attached to the liquid helium vessel and a lower end attached to the liquid helium vessel and an intermediate part attached to an intermediate part of the inner coil support ring at a position spaced from the upper and lower ends of the inner coil support ring

  4. High gradient magnetic separation using superconducting bulk magnets

    International Nuclear Information System (INIS)

    We aim to apply the superconducting bulk magnets to high gradient magnetic separation technique. Two bulk magnets are face-to-face arranged and a pipe stuffed magnetic filters composed of ferromagnetic wires is placed between the magnetic poles. We setup the magnetic separation system and test it using slurry mixed with hematite particles (Fe2O3). Y123 bulk superconductors are magnetized by the 'IMRA' method (pulsed-field magnetization), and consequently a magnetic field of 1.59 T is generated at the center of 20 mm gap between the magnetic poles. As a result of experiment on the magnetic separation, hematite particles of over 90% were removed from slurry at the flow rate of 2 l/min

  5. Magnetic nanoparticles separation based on nanostructures

    International Nuclear Information System (INIS)

    This study describes a magnetic array, which consists of depositing Fe nanowires on a porous alumina membrane. Such a device can be used as a planar magnetic separator. Its performance for the collection of Fe3O4 nanoparticles is experimentally shown. For magnetization of such iron nanowires in the vertical direction, we propose equations to calculate the theoretical absorption ratio

  6. Particle acceleration at a reconnecting magnetic separator

    CERN Document Server

    Threlfall, J; Parnell, C E; Oskoui, S Eradat

    2014-01-01

    While the exact acceleration mechanism of energetic particles during solar flares is (as yet) unknown, magnetic reconnection plays a key role both in the release of stored magnetic energy of the solar corona and the magnetic restructuring during a flare. Recent work has shown that special field lines, called separators, are common sites of reconnection in 3D numerical experiments. To date, 3D separator reconnection sites have received little attention as particle accelerators. We investigate the effectiveness of separator reconnection as a particle acceleration mechanism for electrons and protons. We study the particle acceleration using a relativistic guiding-centre particle code in a time-dependent kinematic model of magnetic reconnection at a separator. The effect upon particle behaviour of initial position, pitch angle and initial kinetic energy are examined in detail, both for specific (single) particle examples and for large distributions of initial conditions. The separator reconnection model contains ...

  7. Magnetic material separation and high superconducting material

    International Nuclear Information System (INIS)

    Full text: Magnetic separation techniques provide an efficient method for the separation of very fine and weak magnetic materials, especially using a high gradient magnetic separator (HGMS). The separation efficiency is mainly related to the strength of the magnetic field applied and the field gradient generated to trap the magnetic particles (the magnetic force of a particle having volume V in magnetic field is described as Fm ?oV(?p-?m) H dH/dx). As a device, HGMS comprises essentially a canister containing a matrix of filamentary magnetic material, which is placed within a strong and relatively uniform magnetic field typically generated by a solenoid magnet, as shown HTS material has interesting relation with the magnetic separation techniques, especially HGMS, and can be summarised as follows: (1) HTS materials can be purified with magnetic separation techniques. This is because the HTS material (powder) has paramagnetic and diamagnetic transition at its critical temperature Tc. By using this method, powders with desired HTS phase can be obtained, e.g. the separation of Bi-2223 and 2212 components. (2) HTS can be used for the design of a matrix used in HGMS with high field gradient. HTS has the nature of quantum flux by unit ?o. The sample designed groups the flux and therefore forming the high gradient magnetic field required for the HGMS matrix. Considering superconductor flux jump stability {g superconductor flux jump stability {Bfj=(?/2)[?oCJc/(dJc/dT)]1/2 by Swart and Bean}, HTS has a much greater value (? 10 times) than LTS, e.g. Bfj YBaCuO is up to 14 T / 77 K (cal.); meanwhile Nb3Sn can only trap 0.9 T at 16 K. (3) HTS can generate high magnetic fields by: (a) HTS bulk can trap very high field, e.g. melt-textured YBaCuO brick having ? 1 T / 77 K; (b) HTS wire can produce high field magnet, e.g. magnet made by (Bi,Pb)2Sr2Ca2Cu3010+x Ag clad HTS wire can generate sufficient magnetic field at an economic operation temperature. HTS techniques provide some advantages to design a HGMS with higher separation efficiency. Magnet made by the (Bi,Pb)2Sr2Ca2Cu3O10+x Ag clad HTS wire is suitable to build a high efficiency HGMS which has widely applications

  8. Magnetic separation of uranium from magnesium fluoride

    International Nuclear Information System (INIS)

    The attraction or repulsion of particles by a magnetic gradient, based on the respective susceptibilities, provides the basis for physical separation of particles that are comprised predominantly of uranium from those that are predominantly magnesium fluoride (MgF2). To determine the effectiveness of this approach, a bench-scale magnetic separator from the S.G. Frantz Co., Inc. was used. In the Frantz Model L-1, particles are fed through a funnel onto a vibration tray and through a magnetic field. The specific design of the Frantz magnet causes the magnetic field strength to vary along the width of the magnet, setting up a gradient. The tray in the magnetic field is split at a point about half way down its length so that the separated material does not recombine. A schematic is presented of Frantz Model L-1 CN - the same magnet configured for high gradient magnetic separation of liquid-suspended particles. Here different pole pieces create a uniform magnetic field, and stainless steel wood in the canister between the pole pieces creates the high gradient. 1 ref., 6 figs., 2 tabs

  9. Open gradient superconducting magnetic separation - an assessment

    International Nuclear Information System (INIS)

    This paper gives an account of the background to the development of superconductor solenoid magnets, capable of generating magnetic field strengths up to 150 tesla or more, up to 2m in diameter. They offer scope for the development of magnetic separation on a large tonnage scale for the concentration and purification of many industrial minerals. The Mark 4 design for open channel wet and dry systems is assessed and the outlook for future progress in superconducting magnetic separators and their use in industry is discussed. (U.K.)

  10. Rapid Characterization of Magnetic Moment of Cells for Magnetic Separation

    OpenAIRE

    Ooi, Chinchun; Earhart, Christopher M.; Wilson, Robert J.; Wang, Shan X.

    2013-01-01

    NCI-H1650 lung cancer cell lines labeled with magnetic nanoparticles via the Epithelial Cell Adhesion Molecule (EpCAM) antigen were previously shown to be captured at high efficiencies by a microfabricated magnetic sifter. If fine control and optimization of the magnetic separation process is to be achieved, it is vital to be able to characterize the labeled cells’ magnetic moment rapidly. We have thus adapted a rapid prototyping method to obtain the saturation magnetic moment of these cell...

  11. Recycling of WEEE by magnetic density separation:

    OpenAIRE

    Hu, B.; Giacometti, L.; Di Maio, F.; Rem, P. C.

    2011-01-01

    The paper introduces a new recycling method of WEEE: Magnetic Density Separation. By using this technology, both grade and recovery rate of recycled products are over 90%. Good separations are not only observed in relatively big WEEE samples, but also in samples with smaller sizes or electrical wires.

  12. A ferromagnetic collector for magnetic separation

    International Nuclear Information System (INIS)

    A ferromagnetic collector for high gradient magnetic separation formed from steels having a chromium content of at least 17% by weight and a carbon content not exceeding 0.03% by weight. Such steels are resistant to attack by acid and are therefore suitable as magnetic collectors in filters employed in acidic environments. (author)

  13. A PURPOSE ORIENTED MAGNETIC SEPARATOR: SKIMMER

    Energy Technology Data Exchange (ETDEWEB)

    Salih Ersayin

    2005-08-09

    A magnetic separator was designed to selectively separate fine-liberated magnetite. The conceptual design was simulated using CFD techniques. A separator tank was fabricated and a magnetic drum was used to capture magnetic particles. The initial tank design was modified to eliminate application oriented problems. The new separator was able to produce a fine product as a concentrate at relatively high feed rates. A plant simulation showed that such a device could lower circulating loads around ball mills by 16%, thereby creating room for a 5-8% increase in throughput at the same energy level. However, it was concluded that further improvements in terms of both size and mineral selectivity are needed to have a marketable product.

  14. Microfluidic magnetic separator using an array of soft magnetic elements

    DEFF Research Database (Denmark)

    Smistrup, Kristian; Lund-Olesen, Torsten

    2006-01-01

    We present the design, fabrication, characterization, and demonstration of a new passive magnetic bead separator. The device operates in an effective state when magnetized by an external magnetic field of only 50 mT, which is available from a tabletop electromagnet. We demonstrate the complete capture of 1.0 mu m fluorescent magnetic beads from a 7.5 mu L sample volume traveling at an average linear fluid velocity of 5 mm/s.

  15. Magnetic separation of uranium from waste materials

    International Nuclear Information System (INIS)

    Criteria were developed for the selection of candidate wastes for testing the magnetic separation of uranium or other paramagnetic materials or both. A survey of Department of Energy (DOE) hazardous wastes was conducted to determine good candidates for bench-scale magnetic separation tests. Representatives of 21 DOE sites were contacted, and materials were identified as potential candidates for magnetic separation. To date, seven samples have been obtained and tested for separability of uranium with a bench-scale magnetic assaying device. The samples tested have been obtained from the K-1401B and K-1401C pounds in Oak Ridge, TN; from waste piles in Maywood, NJ; from North and South Ponds in Richland, WA; and from magnesium fluoride drums in Fernald, OH. The magnetic device utilized in these tests can be used in a deflective mode with dry particulate samples or a matrix-gradient mode with either dry particulate or liquid-suspended materials. Uranium separation from magnesium fluoride has shown exceptionally good performance in both wet and dry systems and could be an important application of the technology

  16. Magnetic separation of uranium from waste materials

    International Nuclear Information System (INIS)

    Criteria were developed for selection of candidate wastes for testing magnetic separation of uranium and/or other paramagnetic materials. A survey of Department of Energy (DOE) hazardous wastes was conducted to determine good candidates for bench-scale magnetic separation tests. Representatives of 21 DOE sites were contacted, and materials were identified as potential candidates for magnetic separation. To date, seven samples have been obtained and tested for separability of uranium with a bench-scale magnetic assaying device. The samples tested have been obtained from the K-1401B and K-1401C ponds in Oak Ridge, Tennessee; from waste piles in Maywood, New Jersey; from North and South Ponds in Richland, Washington; and from magnesium fluoride drums in Fernald, Ohio. The magnetic device utilized in these tests can be used in a deflective mode with dry particulate samples or a matrix-gradient mode with either dry particulate or liquid-suspended materials. Uranium separation from magnesium fluoride has shown exceptionally good performance in both wet and dry systems and could be an important application of the technology. 13 figs., 6 tabs

  17. Loss separation in soft magnetic composites

    OpenAIRE

    La Barrie?re, Olivier; Appino, Carlo; Fiorillo, Fausto; Carlo, Ragusa; Ben Ahmed, Hamid; Gabsi, Mohamed; Mazaleyrat, Fre?de?ric; Lobue, Martino

    2011-01-01

    We report and discuss significant results on the magnetic losses and their frequency dependence in soft magnetic composites. Two types of bonded Fe-based materials have been characterized at different inductions from dc to 10 kHz and analyzed by extending the concept of loss separation and the related statistical theory to the case of heterogeneous materials. Starting from the experimental evidence of eddy current confinement inside the individual particles, the classical loss component is ca...

  18. Magnetic phase separation in ordered alloys

    OpenAIRE

    Marcos, Jordi; Vives I Santa-eula?lia, Eduard; Casta?n I Vidal, Maria Teresa

    2001-01-01

    We present a lattice model to study the equilibrium phase diagram of ordered alloys with one magnetic component that exhibits a low temperature phase separation between paramagnetic and ferromagnetic phases. The model is constructed from the experimental facts observed in Cu$_{3-x}$AlMn$_{x}$ and it includes coupling between configurational and magnetic degrees of freedom which are appropriated for reproducing the low temperature miscibility gap. The essential ingredient for...

  19. Magnetic separation using high-Tc superconductors

    International Nuclear Information System (INIS)

    Superconductivity has found in magnetic separation one of its major industrial applications second only to magnetic resonance imaging. Low-Tc superconducting coils have been employed in High Gradient magnetic Separators (HGMS) since the late 80s, the saving in power consumption overcoming the high costs of the liquid helium refrigeration system. The discovery in 1986 of the high-Tc materials has opened the possibility of cooling with liquid nitrogen or cryocoolers, which represents a considerable simplification of the cryogenics involved and a reduction of capital and running costs. But the present high-Tc materials are not sufficiently developed to simply replace low-Tc coils in the opened solenoid configuration of the HGMS, due to their low critical currents around 77 K. This thesis investigates the employment of a high-Tc superconducting coil in a magnetic separator with an iron yoke. In this application the low-Tc coil supplies Ampereturns to a magnetic circuit, which provides a low reluctance path for the magnetic flux and delivers a magnetic field in the air-gap much higher than the field seen by the coil. A small prototype of such a separator has been built. The superconducting coil, a Bi2S2Ca2Cu3O8 solenoid, has been provided by Intermagnetics General Corporation. The use of high-Tc coil as opposed to resistive ones, however, resus opposed to resistive ones, however, results in different design requirements, ultimately dictated by the sensitivity of the high-Tc material to magnetic fields. Finite elements modelling of the system has provided the framework for the quantitative analysis of the magnetic field distributions on the coil windings and the optimisation of the system configuration. The performance of the separator has been tested at 77 K with liquid nitrogen at atmospheric pressure, and at a temperature ? 67 K by pumping liquid nitrogen at a pressure around 100 Torr. The highest field obtained in the air gap at 67 K was of 340 mT. Magnetic separators with an iron circuit have been in operation for many years in mineral industry, and there appear to be an opportunity of building machines with high-Tc coils or retrofitting existing machines with high-Tc coils to run them closer to saturation in a cheap and effective way. (author)

  20. The separation velocity of emerging magnetic flux

    Science.gov (United States)

    Chou, Dean-Yi; Wang, Haimin

    1987-01-01

    The separation velocities and magnetic fluxes of 24 emerging bipoles on the sun are measured in order to provide data on the emerging mechanism. Velocities are shown to range from about 0.2-1 km/s, bipole fluxes to range over more than two orders of magnitude, and the mean field strength and the sizes to range over one order of magnitude. No correlation is noted between measured separation velocities and either the flux or the mean field strength of the bipole. Predicted separation velocities are found be about one order of magnitude greater than measured values.

  1. Multistage Magnetic Separator of Cells and Proteins

    Science.gov (United States)

    Barton, Ken; Ainsworth, Mark; Daily, Bruce; Dunn, Scott; Metz, Bill; Vellinger, John; Taylor, Brock; Meador, Bruce

    2005-01-01

    The multistage electromagnetic separator for purifying cells and magnetic particles (MAGSEP) is a laboratory apparatus for separating and/or purifying particles (especially biological cells) on the basis of their magnetic susceptibility and magnetophoretic mobility. Whereas a typical prior apparatus based on similar principles offers only a single stage of separation, the MAGSEP, as its full name indicates, offers multiple stages of separation; this makes it possible to refine a sample population of particles to a higher level of purity or to categorize multiple portions of the sample on the basis of magnetic susceptibility and/or magnetophoretic mobility. The MAGSEP includes a processing unit and an electronic unit coupled to a personal computer. The processing unit includes upper and lower plates, a plate-rotation system, an electromagnet, an electromagnet-translation system, and a capture-magnet assembly. The plates are bolted together through a roller bearing that allows the plates to rotate with respect to each other. An interface between the plates acts as a seal for separating fluids. A lower cuvette can be aligned with as many as 15 upper cuvette stations for fraction collection during processing. A two-phase stepping motor drives the rotation system, causing the upper plate to rotate for the collection of each fraction of the sample material. The electromagnet generates a magnetic field across the lower cuvette, while the translation system translates the electromagnet upward along the lower cuvette. The current supplied to the electromagnet, and thus the magnetic flux density at the pole face of the electromagnet, can be set at a programmed value between 0 and 1,400 gauss (0.14 T). The rate of translation can be programmed between 5 and 2,000 m/s so as to align all sample particles in the same position in the cuvette. The capture magnet can be a permanent magnet. It is mounted on an arm connected to a stepping motor. The stepping motor rotates the arm to position the capture magnet above the upper cuvette into which a fraction of the sample is collected. The electronic unit includes a power switch, power-supply circuitry that accepts 110-Vac input power, an RS-232 interface, and status lights. The personal computer runs the MAGSEP software and controls the operation of the MAGSEP through the RS-232 interface. The status of the power, the translating electromagnet, the capture magnet, and the rotation of the upper plate are indicated in a graphical user interface on the computer screen.

  2. Plasma separation from magnetic field lines in a magnetic nozzle

    Science.gov (United States)

    Kaufman, D. A.; Goodwin, D. G.; Sercel, J. C.

    1993-01-01

    This paper discusses conditions for separation of a plasma from the magnetic field of a magnetic nozzle. The analysis assumes a collisionless, quasineutral plasma, and therefore the results represent a lower bound on the amount of detachment possible for a given set of plasma conditions. We show that collisionless separation can occur because finite electron mass inhibits the flow of azimuthal currents in the nozzle. Separation conditions are governed by a parameter G which depends on plasma and nozzle conditions. Several methods of improving plasma detachment are presented, including moving the plasma generation zone downstream from the region of strongest magnetic field and using dual magnets to focus the plasma beam. Plasma detachment can be enhanced by manipulation of the nozzle configuration.

  3. Magnetic affinity separation of recombinant fusion proteins.

    Czech Academy of Sciences Publication Activity Database

    Šafa?ík, Ivo; Šafa?íková, Miroslava

    2010-01-01

    Ro?. 38, ?. 1 (2010), s. 1-7. ISSN 1303-5002 R&D Projects: GA MŠk(CZ) OC 157; GA MPO(CZ) 2A-1TP1/094 Institutional research plan: CEZ:AV0Z60870520 Keywords : recombinant fusion proteins * affinity tags * magnetic separation Subject RIV: CE - Biochemistry

  4. Simplified theory of multipole superconducting magnetic separator

    International Nuclear Information System (INIS)

    Different configurations of coils have been proposed for multipole superconducting magnetic separators. The analysis of their magnetic fields allowed finding expressions for magnetic force F/sub m/, which depends mainly on the reduced distance d/sub/ tau/ from the winding symmetry surface, (tau being the pole distance and the basic design parameter). Tau can be optimized to give maximum F/sub m/ at a given d/sub i/, e.g., at the middle of the working channel. It has been shown that in the working channel F/sub m/ can be approximated by a linear function of d/sub/ tau/ that allows finding expressions for particle trajectories as well as for main separator characteristics. 10 refs

  5. Magnetic phase separation in ordered alloys

    CERN Document Server

    Marcos, J; Castan, T; Marcos, Jordi; Vives, Eduard; Castan, Teresa

    2001-01-01

    We present a lattice model to study the equilibrium phase diagram of ordered alloys with one magnetic component that exhibits a low temperature phase separation between paramagnetic and ferromagnetic phases. The model is constructed from the experimental facts observed in Cu$_{3-x}$AlMn$_{x}$ and it includes coupling between configurational and magnetic degrees of freedom which are appropriated for reproducing the low temperature miscibility gap. The essential ingredient for the occurrence of such a coexistence region is the development of ferromagnetic order induced by the long-range atomic order of the magnetic component. A comparative study of both mean-field and Monte Carlo solutions is presented. Moreover, the model may enable the study of the structure of the ferromagnetic domains embedded in the non-magnetic matrix. This is relevant in relation to phenomena such as magnetoresistance and paramagnetism.

  6. Separation of magnetic affinity biopolymer adsorbents in a Davis tube magnetic separator.

    Czech Academy of Sciences Publication Activity Database

    Šafa?ík, Ivo; Mucha, Pavel; Pecho?, Ji?í; Stoklasa, Jaroslav; Šafa?íková, Miroslava

    2001-01-01

    Ro?. 23, - (2001), s. 851-855. ISSN 0141-5492 R&D Projects: GA ?R GA203/98/1145 Institutional research plan: CEZ:AV0Z6087904 Keywords : Davis tube * magnetic adsorbents * magnetic separation Subject RIV: EI - Biotechnology ; Bionics Impact factor: 0.915, year: 2001

  7. Medical protein separation system using high gradient magnetic separation by superconducting magnet

    Science.gov (United States)

    Kamioka, Y.; Agatsuma, K.; Kajikawa, K.; Ueda, H.; Furuse, M.; Fuchino, S.; Iitsuka, T.; Nakamura, S.

    2014-01-01

    A high gradient magnetic separation system for medical protein using affinity magnetic nano-beads has been developed. Medical protein such as monoclonal antibody or immunoglobulin is an important substance as a medicine for cancer etc. However; the separation system of these medical protein has very low separation rate and the cost of product is extremely high. The developed system shows very high separation efficiency and can achieve low cost by large production rate compared to the system now using in this field. The system consists of a 3T superconducting magnet cooled by a cryo-cooler, a filter made of fine magnetic metal wires of about 30?m diameter and a demagnetization circuit and a liquid circulation pump for solvent containing medical protein. Affinity magnetic nano-beads is covered with the medical protein after agitation of solvent containing the protein and nano-beads, then the solvent flows through the system and the beads are trapped in the filters by high gradient magnetic field. The beads are released and flow out of the system by the AC demagnetization of the filters using LC resonance circuits after discharge of the magnet. The test results shows 97.8% of the magnetic nano-beads in pure water were captured and 94.1% of total beads were collected.

  8. A new industrial application of magnetic separation

    International Nuclear Information System (INIS)

    The aim of this work was to investigate the application of magnetic separation to the removal and recovery of carbon steel grinding swarf from machining fluids used in large-scale industrial manufacturing processes such as in the automotive industry. Magnetic separation is a technology which has found widespread application in the mineral processing industry and in particular the beneficiation of kaolin clay for use in the paper industry. The technical feasibility of the application was demonstrated in the early stages of the work by the successful treatment of industrial samples using a crude laboratory-scale separator. In addition, the fluid and swarf material underwent extensive analysis using electron microscope-based optical and spectroscopic techniques in order to ascertain the presence of other undesirable components of the fluid that would require removal also. It was demonstrated by these results that the overall objective of the project was the development and testing of a laboratory-scale system which would allow the optimum operational parameters to be ascertained for the design of a commercially viable, large-scale system. A series of detailed trials on large volumes of industrial samples was carried out in conjunction with the development of the modifications that were required to existing magnetic separation theory in order to accommodate the particulars of this application. The trial system was tested to low applied magnetic strengths and high fluid flplied magnetic strengths and high fluid flow velocities in order to optimise the economics of the application, resulting in extraction efficiencies of the order of 99.998% being achieved. During the course of the project, a new type of matrix cleaning system was developed for which a patent was applied and this was successfully tested in the trial system. Economic appraisal of the application suggests that an industrial-scale system could provide reliable, high quality recovery of grinding swarf at a cost of around one cent per cubic metre of fluid. Overall, the results from the project have provided the foundation for the application of magnetic separation to this application. (author)

  9. Fundamental study of phosphor separation by controlling magnetic force

    International Nuclear Information System (INIS)

    Highlights: •We tried to separate the phosphor using the magnetic Archimedes separation method. •In this method, vertical and radial components of the magnetic force were used. •We succeeded to separate HP and developed the continuous separation system. •The separation system enables successive separation and recovery of HP. -- Abstract: The phosphor wastes consist of phosphors with different emission colors, green (LAP), red (YOX), blue (BAM) and white (HP). It is required to recover and reuse the rare earth phosphors with high market value. In this study, we tried to separate the phosphor using the magnetic separation by HTS bulk magnet utilizing the differences of magnetic susceptibility by the type of phosphors. We succeeded in the successive separation of HP with low market value from YOX and BAM including the rare earth using the magnetic Archimedes method. In this method, vertical and radial components of the magnetic force were used

  10. Optimizing the performance of wet drum magnetic separators

    Scientific Electronic Library Online (English)

    M., Dworzanowski.

    2010-11-01

    Full Text Available The difference in the magnetic properties of minerals is the basis for magnetic separation. All minerals can be generally classified as ferromagnetic (strongly magnetic), paramagnetic (weakly magnetic) or diamagnetic (non-magnetic). Magnetic separation can be conducted dry or wet. The majority of th [...] e applications of wet magnetic separation in the mining industry are based on the wet drum magnetic separator. The wet drum magnetic separator has been in use for over 50 years and its design is based on a rotating drum installed inside a tank. Inside the drum are stationary, permanent magnets arranged in an arc to provide the magnetic field. These magnets can be of the ceramic ferrite type providing a low intensity magnetic field or of the rare earth type providing a high intensity magnetic field. Wet drum magnetic separators are generally applied in three different ways, namely to recover and recycle the medium used in dense medium separation (DMS), to remove magnetic contaminants from ores and concentrates, and to recover valuable magnetic products. Wet drum magnetic separators are applied in the following commodity areas: coal, diamonds, iron ore, chrome, platinum, heavy mineral sands, industrial minerals, and base metals. Whereas the design and operation of wet drum magnetic separators is relatively straightforward, it is very often found that the performance of wet drum magnetic separators is far from optimum. The reason for this is generally a lack of understanding of how the different design and operating variables interact and how they affect performance. This paper examines these variables, describing their importance and impact for all applications of wet drum magnetic separators. It also provides clear guidelines on how to adjust and control these variables so that optimum performance is achieved.

  11. Fundamental study on magnetic separation of organic dyes in wastewater

    International Nuclear Information System (INIS)

    The objective of this study is to separate dyes in wastewater with high efficiency and speed using High Gradient Magnetic Separation with superconducting magnet. Two main technologies are necessary for magnetic separation; one is magnetic seeding technology to provide ferromagnetism to the substance, and the other is magnetic separation technology using superconducting magnet and magnetic filters. In order to separate organic dyes, it is necessary to clarify the mechanism of magnetic seeding, and to design a suitable magnetic seeding method depending on the kind of object dye. Six kinds of dyes which are widely used in industry were adopted to investigate the possibility of the magnetic seeding and interaction mechanism between dye and ferromagnetic particles. As a result, it was shown that electrostatic interaction is one of the main interactions between organic dye and ferromagnetic particles.

  12. Environmental clean-up by magnetic separation. Volume reduction of contaminated soil by superconducting magnetic separation

    International Nuclear Information System (INIS)

    The reactor meltdown of the Fukushima Daiichi Nuclear Power Plants released radioactive materials in the environment. For the decontamination of the Cs 137 contaminated soils, the present author proposes to use the magnetic separation method to classify the contaminated soils into clay or silt stones and the gravel sands while it is known that most radioactive cesium combines tightly with finer particulates (clay stones) to be stored or repositioned and the rest to be back-filled. Molecular mechanism for cesium ion adsorption with clay minerals is discussed. It is confirmed that the present superconducting magnetic separation method is useful and efficient for reducing the volume of decontaminated soils. (S. Ohno)

  13. Magnetic force on a magnetic particle within a high gradient magnetic separator

    Science.gov (United States)

    Baik, S. K.; Ha, D. W.; Kwon, J. M.; Lee, Y. J.; Ko, R. K.

    2013-01-01

    HGMS (High Gradient Magnetic Separator) uses matrix to make high magnetic field gradient so that ferro- or para-magnetic particles can be attracted to them by high magnetic force. The magnetic force generated by the field gradient is several thousand times larger than that by background magnetic field alone. So the HGMS shows excellent performance compared with other magnetic separators. These matrixes are usually composed of stainless steel wires having high magnetization characteristics. This paper deals with superconducting HGMS which is aimed for purifying waste water by using stainless steel matrix. Background magnetic field up to 6 T is generated by a superconducting solenoid and the stainless steel matrixes are arranged inside of the solenoid. Based on magnetic field calculated by FEM (Finite Element Method), we could calculate magnetic force acting on a magnetic particle such as hematite and maghemite consisting of major impurities in the condenser water of a thermal power station.

  14. Prediction of Separation Performance of Dry High Intensity Magnetic Separator for Processing of Para-Magnetic Minerals

    Science.gov (United States)

    Tripathy, Sunil Kumar; Singh, Veerendra; Suresh, Nikkam

    2015-03-01

    High intensity dry magnetic separators are gaining popularity for the separation of para-magnetic minerals due to the cost economic factor. Induced roll magnetic separator is found to be an effective dry separator for the separation of fine particles. Separation efficiency of this separator depends on mineral characteristics and the design features of equipment along with the optimization of process variables. Present investigation focuses on the prediction and validation of separation performance of minerals while treating in induced roll magnetic separator. Prediction of the separation is expressed in terms of separation angle at which a particle leaves the rotor surface by using a modified particle flow model derived by Cakir. The validation of the model is carried by capturing the particle trajectory using an image analyzer. It is found that Cakir's mathematical model produces reliable results and a new model is proposed to increase the reliability of separation angle prediction by including the particle shape factor.

  15. Magnetic circuit with large blocks from NdFeB magnets for suspended magnetic separators.

    Czech Academy of Sciences Publication Activity Database

    Žežulka, Václav

    2010-01-01

    Ro?. 7, ?. 2 (2010), s. 227-235. ISSN 1214-9705 Institutional research plan: CEZ:AV0Z30460519 Keywords : magnetic circuits * magnetic separation * permanent magnets Subject RIV: BM - Solid Matter Physics ; Magnetism Impact factor: 0.452, year: 2010 www.irsm.cas.cz/?Lang=CZE&Menu=25,0,0,0

  16. Wet high-intensity magnetic separation

    International Nuclear Information System (INIS)

    Miscellaneous laboratory tests (most of them on cyanide residues) were undertaken to supplement on-site pilot-plant work on wet high intensity magnetic separation (WHIMS). Initially, the main concern was with blockage of the matrix, and consideration was given to the use of a reverse-flushing system. The laboratory tests on this system were encouraging, but they were not of sufficiently long duration to be conclusive. The velocity of the pulp through the matrix is important, because it determines the capacity of the separator and the recovery obtainable. Of almost equal importance is the magnetic load, which affects the velocity of the pulp and the recovery. Typically, a recovery of 51 per cent of the uranium was reduced to one of 40 per cent as the magnetic load was increased from 25 to 100 g/l, while the pulp velocity decreased from 62 to 36 mm/s. There was some indication that, for the same pulp velocity, lower recoveries are obtained when free-fall feeding is used. Some benefit was observed in the application of WHIMS to coarsely ground ore; from a Blyvooruitzicht rod-mill product, 25 per cent of the total uranium was recovered when only 29 per cent of the rod-mill product (the finest portion) was treated. A similar recovery was made from 43 per cent of the rod-mill product from Stilfontein; a second stage of treatment after regrinding raised the overall recovery of uranium to 76,4 per cent. Recoveries of 55 and 42 per cent of the uranium were obtained in tests on two flotation tailings from Free State Geduld. In a determination of the mass magnetic susceptibilities of the constituents in a typical concentrate obtained by WHIMS, it was found that some 20 per cent of the magnetic product had a susceptibility of less than 5,4 X 10-6 e.m.u. but contained 38 per cent of the uranium recovered by WHIMS. A few tests were conducted on different types of matrix. A matrix of spaced horizontal rods is recommended for possible future consideration

  17. Integrated acoustic and magnetic separation in microfluidic channels

    OpenAIRE

    Adams, Jonathan; Thevoz, Patrick; Bruus, Henrik; Soh, H. Tom

    2009-01-01

    With a growing number of cell-based biotechnological applications, there is a need for particle separation systems capable of multiparameter separations at high purity and throughput, beyond what is presently offered by traditional methods including fluorescence activated cell sorting and column-based magnetic separation. Toward this aim, we report on the integration of microfluidic acoustic and magnetic separation in a monolithic device for multiparameter particle separation. Using our devic...

  18. Magnetic force on a magnetic particle within a high gradient magnetic separator

    International Nuclear Information System (INIS)

    Highlights: ? Magnetic field and the gradient decide magnetic force on a particle in HGMS (High Gradient Magnetic Separation). ? We calculated the field and the gradient of a superconducting HGMS system by finite element method. ? We could calculate magnetic force on a particle consisting of major impurities in the condenser water of a thermal power station. -- Abstract: HGMS (High Gradient Magnetic Separator) uses matrix to make high magnetic field gradient so that ferro- or para-magnetic particles can be attracted to them by high magnetic force. The magnetic force generated by the field gradient is several thousand times larger than that by background magnetic field alone. So the HGMS shows excellent performance compared with other magnetic separators. These matrixes are usually composed of stainless steel wires having high magnetization characteristics. This paper deals with superconducting HGMS which is aimed for purifying waste water by using stainless steel matrix. Background magnetic field up to 6 T is generated by a superconducting solenoid and the stainless steel matrixes are arranged inside of the solenoid. Based on magnetic field calculated by FEM (Finite Element Method), we could calculate magnetic force acting on a magnetic particle such as hematite and maghemite consisting of major impurities in the condenser water of a thermal power station

  19. Separation of magnetic susceptibility components from magnetization curves

    Science.gov (United States)

    Kosareva, L.; Nourgaliev, D.; Kuzina, D.; Spassov, S.; Fattakhov, A.

    2014-12-01

    Modern lake sediments are a unique source of information for climate changes, regionally and globally, because all environmental variations are recorded by these sediments with high resolution. The magnetic properties of Chernyshov Bay (Aral Sea) sediments we investigated from core number 4 (N45o57'04.2''; E59o17'14.3'') are taken at far water depth of 9.5 m. The length of the core is 4.16 m. Samples for measurements were taken to plastic sample boxes with internal dimensions 2x2x2 cm. Remanent magnetization curves were measured by coercivity spectrometer for the separate determination of the different contributions to the total bulk magnetic susceptibility. There was measured also magnetic susceptibility using MS2 susceptibility meter. Those operations were done for data comparison between 2 susceptibilities obtained from different equipment. Our goal is to decipher the magnetic susceptibility signal in lake sediments by decomposing the bulk susceptibility signal of a lake sediment sequence into ferromagnetic (?f), dia-/paramagnetic (?p) and superparamagnetic (?sp) components using data from remanent and indused magnetization curves Each of these component has a different origin: paramagnetic minerals are usually attributed to terrigenous sediment input, ferromagnetics are of biogenic origin, and superparamagnetic minerals may be of either biogenic or terrigenous origin. Comparison between susceptibility measurements of MS2-Bartington susceptometer and of the coercivity spectrometer has shown good correlation. The susceptibility values measured in two different equipment are fairly close and indicate thus the reliability the proposed method. In research also has shown water level changes in Aral Sea based on magnetic susceptibility. The work is performed according to the Russian Government Program of Competitive Growth of Kazan Federal University also by RFBR research projects No. 14-05-31376 - ?, 14-05-00785- ?.

  20. Magnetic separation technique for environmental water purification by strong magnetic field generator loading HTS bulk magnets

    International Nuclear Information System (INIS)

    The magnetic separation technique in combination with high temperature superconducting bulk magnets has been investigated to purify the ground water which has been used in the coolant system for the incinerator furnace to cool the burning gas. The experiment has been operated by means of the newly-built alternating channel type magnetic separating device. The separation ratios of ferromagnetic flocks including fine magnetite powder have been estimated by means of the high gradient magnetic separation method with small iron balls filled in the water channels. As the magnetic force acting on the magnetic particle is given by the product of a magnetization of the material and a gradient of magnetic field, and as the ferromagnetic stainless steel balls yield the steep gradient of magnetic field around them in a strong magnetic field, the system has exhibited a quite excellent performance with respect to the separation ratios. The separation ratios of the flocks which contain the magnetite powder with the values more than 50 ppm have remained over 80% for under the flow rates less than 5 L/min.

  1. Highly efficient magnetic separation using five-aligned superconducting bulk magnet

    International Nuclear Information System (INIS)

    We have constructed the highly efficient magnetic separation system using five-aligned superconducting bulk magnets, which has ten usable magnetic poles on both sides in open space. We applied the bulk magnet system to the magnetic separation of ferromagnetic particles (magnetite; Fe3O4) and paramagnetic ones (?-hematite; Fe2O3) dispersed in water for various average particle diameters d, flow speeds VF and initial concentrations C0 of the particles. The multi-bulk magnet system has been confirmed to be effective for the magnetic separation and the efficiency of the magnetic separation per one magnetic pole has been estimated using the theoretical relation.

  2. MSWI boiler fly ashes: magnetic separation for material recovery.

    Science.gov (United States)

    De Boom, Aurore; Degrez, Marc; Hubaux, Paul; Lucion, Christian

    2011-07-01

    Nowadays, ferrous materials are usually recovered from Municipal Solid Waste Incineration (MSWI) bottom ash by magnetic separation. To our knowledge, such a physical technique has not been applied so far to other MSWI residues. This study focuses thus on the applicability of magnetic separation on boiler fly ashes (BFA). Different types of magnet are used to extract the magnetic particles. We investigate the magnetic particle composition, as well as their leaching behaviour (EN 12457-1 leaching test). The magnetic particles present higher Cr, Fe, Mn and Ni concentration than the non-magnetic (NM) fraction. Magnetic separation does not improve the leachability of the NM fraction. To approximate industrial conditions, magnetic separation is also applied to BFA mixed with water by using a pilot. BFA magnetic separation is economically evaluated. This study globally shows that it is possible to extract some magnetic particles from MSWI boiler fly ashes. However, the magnetic particles only represent from 23 to 120 g/kg of the BFA and, though they are enriched in Fe, are composed of similar elements to the raw ashes. The industrial application of magnetic separation would only be profitable if large amounts of ashes were treated (more than 15 kt/y), and the process should be ideally completed by other recovery methods or advanced treatments. PMID:21306886

  3. Functionalized silica coated magnetic nanoparticles with biological species for magnetic separation

    OpenAIRE

    Yu, Ch; Tam, Ky; Lo, Cch; Tsang, Sc

    2007-01-01

    Magnetic nanoparticle captured in a thin functional coating as magnetic separable nano-vehicle for carrying chemical species is a hot and challenging area. Here, we report a synthesis of silica encapsulated magnetic nanosize particles (4-11 nm) as a magnetic separable carrier based on a simple microemulsion technique. The silica coating surface is shown to isolate and protect the magnetic core from reactive environment where a range of conditions for magnetic separation can be made possible. ...

  4. Inverted Linear Halbach Array for Separation of Magnetic Nanoparticles

    OpenAIRE

    Ijiri, Y.; Poudel, C.; Williams, P. S.; Moore, L. R.; Orita, T; Zborowski, M.

    2013-01-01

    A linear array of Nd-Fe-B magnets has been designed and constructed in an inverted Halbach configuration for use in separating magnetic nanoparticles. The array provides a large region of relatively low magnetic field, yet high magnetic field gradient in agreement with finite element modeling calculations. The magnet assembly has been combined with a flow channel for magnetic nanoparticle suspensions, such that for an appropriate distance away from the assembly, nanoparticles of higher moment...

  5. Study on magnetic separation of nanosized ferromagnetic particles

    International Nuclear Information System (INIS)

    In recent researches in medicine and the pharmaceutical sciences, the magnetic separation technology using nanosized ferromagnetic particle is essential. For example, in the field of cell engineering, magnetic separation of nanosized ferromagnetic particles is necessary, but separation technology of nanosized particle using magnetic force has not been established. One of the reasons is that magnetic force acting on the object particles decreases as particle diameter becomes small, and makes magnetic separation difficult. In this study, magnetic force acting on the separation object was enlarged by the combination of superconducting magnet and the filter which consists of ferromagnetic particle. As a result of particle trajectory calculation and magnetic separation experiment, it was confirmed that the ferromagnetic particles of 15nm in diameter can be trapped in the magnetic filter under an external magnetic field of 0.5T. The ferromagnetic particles of 6nm in diameter which could not be separated under the same condition could also be trapped under 2.0T of external magnetic field.

  6. A feasibility study of magnetic separation of magnetic nanoparticle for forward osmosis.

    Science.gov (United States)

    Kim, Y C; Han, S; Hong, S

    2011-01-01

    It was recently reported that a UK company has developed a naturally non-toxic magnetoferritin to act as a draw solute for drawing water in forward osmosis process. The gist of this technology is the utilization of the magnetic nanoparticle and high-gradient magnetic separation for draw solute separation and reuse. However, any demonstration on this technology has not been reported yet. In this study, a feasibility test of magnetic separation using magnetic nanoparticle was therefore performed to investigate the possibility of magnetic separation in water treatment such as desalination. Basically, a magnetic separation system consisted of a column packed with a bed of magnetically susceptible wools placed between the poles of electromagnet and Fe3O4 magnetic nanoparticle was used as a model nanoparticle. The effect of nanoparticle size to applied magnetic field in separation column was experimentally investigated and the magnetic field distribution in a magnet gap and the magnetic field gradient around stainless steel wool wire were analyzed through numerical simulation. The amount of magnetic nanoparticle captured in the separator column increased as the magnetic field strength and particle size increased. As a result, if magnetic separation is intended to be used for draw solute separation and reuse, both novel nanoparticle and large-scale high performance magnetic separator must be developed. PMID:22097022

  7. Integrated acoustic and magnetic separation in microfluidic channels

    DEFF Research Database (Denmark)

    Adams, Jonathan; Thevoz, Patrick

    2009-01-01

    With a growing number of cell-based biotechnological applications, there is a need for particle separation systems capable of multiparameter separations at high purity and throughput, beyond what is presently offered by traditional methods including fluorescence activated cell sorting and column-based magnetic separation. Toward this aim, we report on the integration of microfluidic acoustic and magnetic separation in a monolithic device for multiparameter particle separation. Using our device, we demonstrate high-purity separation of a multicomponent particle mixture at a throughput of up to 10(8) particles/hr. (C) 2009 American Institute of Physics. [doi:10.1063/1.3275577

  8. Development of high gradient magnetic separation system under dry condition

    Science.gov (United States)

    Nakai, Y.; Mishima, F.; Akiyama, Y.; Nishijima, S.

    2010-11-01

    The interfusion of impurities such as metallic wear debris has been a problem in the manufacturing process of foods, medicines, and industrial products. Gravity separation system and membrane separation system has been used widely for powder separation, however magnetic separation system is much efficient to separate magnetic particles. Magnetic separation system under wet process is used conventionally, however, it has some demerit such as necessity of drying treatment after separation and difficulty of running the system in the cold region and so on. Thus, magnetic separation under dry process is prospective as alternative method. In this paper, we developed high gradient magnetic separation system (HGMS) under dry process. In dry HGMS system, powder coagulation caused by particle interaction is considerable. Powder coagulation causes a blockage of magnetic filters and results in decrease of separation performance of dry HGMS system. In order to investigate the effect of powder coagulation on separation performance, we conducted experiments with two kinds of powdered materials whose cohesive properties are different.

  9. Development of high gradient magnetic separation system under dry condition

    International Nuclear Information System (INIS)

    The interfusion of impurities such as metallic wear debris has been a problem in the manufacturing process of foods, medicines, and industrial products. Gravity separation system and membrane separation system has been used widely for powder separation, however magnetic separation system is much efficient to separate magnetic particles. Magnetic separation system under wet process is used conventionally, however, it has some demerit such as necessity of drying treatment after separation and difficulty of running the system in the cold region and so on. Thus, magnetic separation under dry process is prospective as alternative method. In this paper, we developed high gradient magnetic separation system (HGMS) under dry process. In dry HGMS system, powder coagulation caused by particle interaction is considerable. Powder coagulation causes a blockage of magnetic filters and results in decrease of separation performance of dry HGMS system. In order to investigate the effect of powder coagulation on separation performance, we conducted experiments with two kinds of powdered materials whose cohesive properties are different.

  10. Microfabricated magnetic sifter for high-throughput and high-gradient magnetic separation

    OpenAIRE

    Earhart, Christopher M.; Wilson, Robert J.; White, Robert L.; Pourmand, Nader; Wang, Shan X.

    2009-01-01

    A microfabricated magnetic sifter has been designed and fabricated for applications in biological sample preparation. The device enables high-throughput, high-gradient magnetic separation of magnetic nanoparticles by utilizing columnar fluid flow through a dense array (~5000/mm2) of micropatterned slots in a magnetically soft membrane. The potential of the sifter for separation of magnetic nanoparticles conjugated with capture antibodies is demonstrated through quantitative separation experim...

  11. Application of high gradient magnetic separation in nuclear fuel reprocessing

    International Nuclear Information System (INIS)

    This paper discusses high gradient magnetic separation (HGMS), a new solids removal technique in which paramagnetic solids can be trapped in a separator by magnetic forces and then flushed out when the field is switched off. Theoretical formulas are presented that enable equipment to be specified at least approximately. The method has important potential advantages for nuclear fuel reprocessing. 25 refs

  12. High gradient magnetic separation applied to environmental remediation

    International Nuclear Information System (INIS)

    High Gradient Magnetic Separation (HGMS) is an application of superconducting magnet technology to the separation of magnetic solids from other solids, liquids, or gases. The production of both high magnetic fields (>4 T) and large field gradients using superconducting magnet technology has made it possible to separate a previously unreachable but large family of paramagnetic materials. This is a powerful technique that can be used to separate widely dispersed contaminants from a host material and may be the only technique available for separating material in the colloidal state. Because it is a physical separation process, no additional waste is generated. We are applying this technology to the treatment of radioactive wastes for environmental remediation. We have conducted tests examining slurries containing nonradioactive, magnetic surrogates. Results from these studies were used to verify our analytical model of the separation process. The model describes the rate process for magnetic separation and is based on a force balance on the paramagnetic species. This model was used to support bench scale experiments and prototype separator design

  13. High gradient magnetic separation applied to environmental remediation

    International Nuclear Information System (INIS)

    High gradient magnetic separation (HGMS) is an application of superconducting magnet technology to the separation of magnetic solids from other solids, liquids, or gases. The production of both high magnetic fields (>4 T) and large field gradients using superconducting magnet technology has made it possible to separate a previously unreachable but large family of paramagnetic materials. This powerful technique can be used to separate widely dispersed contaminants from a host material, and it may be the only technique available for separating material in the colloidal state. Because it is a physical separation process, no additional waste is generated. The authors are applying this technology to the treatment of radioactive wastes for environmental remediation. They have conducted tests examining slurries containing nonradioactive, magnetic surrogates. Results from these studies were used to verify their analytical model of the separation process. The model describes the rate process for magnetic separation and is based on a force balance on the paramagnetic species. This model was used to support bench scale experiments and prototype separator designs

  14. Magnetic separation of micro-spheres from viscous biological fluids

    International Nuclear Information System (INIS)

    A magnetically based detoxification system is being developed as a therapeutic tool for selective and rapid removal of biohazards, i.e. chemicals and radioactive substances, from human blood. One of the key components of this system is a portable magnetic separator capable of separating polymer-based magnetic nano/micro-spheres from arterial blood flow in an ex vivo unit. The magnetic separator consists of an array of alternating and parallel capillary tubing and magnetizable wires, which is exposed to an applied magnetic field created by two parallel permanent magnets such that the magnetic field is perpendicular to both the wires and the fluid flow. In this paper, the performance of this separator was evaluated via preliminary in vitro flow experiments using a separator unit consisting of single capillary glass tubing and two metal wires. Pure water, ethylene glycol-water solution (v:v = 39:61 and v:v = 49:51) and human whole blood were used as the fluids. The results showed that when the viscosity increased from 1.0 cp to 3.0 cp, the capture efficiency (CE) decreased from 90% to 56%. However, it is still feasible to obtain >90% CE in blood flow if the separator design is optimized to create higher magnetic gradients and magnetic fields in the separation area

  15. Feasibility of magnetic chromatography for ultra-fine particle separation

    International Nuclear Information System (INIS)

    We propose a new technique that uses magnetic chromatography for continuous separation of ultrafine particles (i.e. -3 and a diameter of about 100 to 150 A. Our magnetic chromatography can be done by applying flow fractionation to the concentration distribution in a channel from 5 to 50 ?m thick and using embedded ferromagnetic wires from 2 to 20 ?m in diameter. A simplified numerical simulation of our magnetic chromatography technique suggests the potential of separating very weak paramagnetic materials (e.g., a nuclear fuel element and Nd) which we have not been able to deal with through the conventional high-gradient magnetic separation techniques. (author)

  16. Characteristics of magnetic field induction inside a module of a magnetic separator ?????????????? ???????? ???? ? ?????? ?????????? ??????????

    Directory of Open Access Journals (Sweden)

    Sandulyak Anna Aleksandrovna

    2013-05-01

    Full Text Available Characteristics of magnetic separators are analyzed in the article. Magnetic separators are used to treat various construction materials. Unfortunately, the nature of the magnetic field, generated in their operating zone, is generally not taken into account by their designers. Academic publications fail to provide any detailed basic characteristics of the field induction emitted by magnetic separators in the course of their operation.Magnetic systems of any magnetic separator have a modular structure; they consist of several modules. Single and opposite magnetic elements are usually integrated into one module within a system having permanent magnets. If opposite magnetic elements are used, magnetic field intensity inside the module increases.In this study, characteristics of magnetic induction for single magnetic elements inside various modules of magnetic separators were assessed in a laboratory experiment. Similar characteristics of magnetic induction for single and twin (opposite magnetic elements were compared. In the module consisting of two opposed magnetic elements, the magnetic field becomes stronger compared to the field of a single magnetic element. Magnetic induction in the module recedes as the distance between magnetic elements increases, because of the isolation of the field generated by the opposed magnetic elements.The authors have proven the feasibility and expediency of employment of the superposition principle used to obtain the resulting characteristics. It may be employed to substitute modeling by calculations.???????????????? ???????? ?????????????? ???????? ?????????? ???? ??? ????????? ????????? ? ????????? ??????? ????????? ???????????. ???????????? ?????????????? ???????? ?????????? ???? ??? ????????? ? ????????? ????????? ????????? ??????. ? ??????, ????????? ? ???? ?????????????? ????????? ?????????, ???? ??????????? ?? ????????? ? ????? ?????????? ?????????? ????????, ???? ?? ???? ?????????? ???????????? ?????????? ??????? ???????? ? ?????? ????????? ?? ???? ??? ???????? «??????????» ????????? ?????, ??????????? ??????????????? ?????????? ??????????.???????? ??????????? ? ???????????? ???????????????? ????????????? ???????? ???????????? ??? ???????????? ?????????????? ?????????????? ???????? ???? ????? ??????????????? ?????????? ?????????? ??? ?????? ????????? ????????????? ?????????.

  17. Rare Cell Separation and Analysis by Magnetic Sorting

    OpenAIRE

    Zborowski, Maciej; Chalmers, Jeffrey J.

    2011-01-01

    The separation and or isolation of rare cells using magnetic forces is commonly used and growing in use ranging from simple sample prep for further studies to a FDA approved, clinical diagnostic test. This grown is the result of both the demand to obtain homogeneous rare cells for molecular analysis and the dramatic increases in the power of permanent magnets that even allow the separation of some unlabeled cells based on intrinsic magnetic moments, such as malaria parasite-infected red blood...

  18. Pair separation of magnetic elements in the quiet Sun

    OpenAIRE

    Giannattasio, F.; Berrilli, F.; Biferale, L.; Del Moro, D.; Sbragaglia, M.; Rubio, L. Bellot; Gosic, M.; Suarez, D. Orozco

    2014-01-01

    The dynamic properties of the quiet Sun photosphere can be investigated by analyzing the pair dispersion of small-scale magnetic fields (i.e., magnetic elements). By using $25$ hr-long Hinode magnetograms at high spatial resolution ($0".3$), we tracked $68,490$ magnetic element pairs within a supergranular cell near the disk center. The computed pair separation spectrum, calculated on the whole set of particle pairs independently of their initial separation, points ou...

  19. Magnetic field trimming studies for a separated-sector cyclotron

    International Nuclear Information System (INIS)

    Magnetic field studies were made for a four-sector, K = 330 (E = Kq2/A MeV), separated-sector cyclotron using a 1/10 scale model of a single sector equipped with 11 trimming coils. Data are presented showing the effects of saturation at high magnetic fields on the field contour and on the trimming coil characteristics. Some implications of these measurements for the design of separated-sector machine magnets are given. (U.S.)

  20. Harvesting fresh water and marine algae by magnetic separation: screening of separation parameters and high gradient magnetic filtration.

    Science.gov (United States)

    Cerff, Martin; Morweiser, Michael; Dillschneider, Robert; Michel, Aymeé; Menzel, Katharina; Posten, Clemens

    2012-08-01

    In this study, the focus is on magnetic separation of fresh water algae Chlamydomonas reinhardtii and Chlorella vulgaris as well as marine algae Phaeodactylum tricornutum and Nannochloropsis salina by means of silica-coated magnetic particles. Due to their small size and low biomass concentrations, harvesting algae by conventional methods is often inefficient and cost-consuming. Magnetic separation is a powerful tool to capture algae by adsorption to submicron-sized magnetic particles. Hereby, separation efficiency depends on parameters such as particle concentration, pH and medium composition. Separation efficiencies of >95% were obtained for all algae while maximum particle loads of 30 and 77 g/g were measured for C. reinhardtii and P. tricornutum at pH 8 and 12, respectively. This study highlights the potential of silica-coated magnetic particles for the removal of fresh water and marine algae by high gradient magnetic filtration and provides critical discussion on future improvements. PMID:22705536

  1. Remediation of Hanford tank waste using magnetic separation

    International Nuclear Information System (INIS)

    Large volumes of high-level radioactive waste are stored at the Department of Energy's Hanford site. Magnetic separation, a physical separation, process, can be used to segregate actinides and certain fission products from the waste. High gradient magnetic separation (HGMS) tests have been performed successfully using a simulated, nonradioactive underground storage tank (UST) waste. Variations in HGMS test parameters included separator matrix material, magnetic field strength, slurry surfactant, and slurry solids loading. Cerium was added to the simulated tank waste to act as a uranium surrogate. Results show that over 77% of the uranium surrogate can be captured and concentrated from the original bulk with a simple procedure. The results of these tests and the feasibility of magnetic separation for pretreatment of UST waste are discussed

  2. Optimizing colloidal dispersity of magnetic nanoparticles based on magnetic separation with magnetic nanowires array

    Science.gov (United States)

    Sun, Jianfei; He, Miaomiao; Liu, Xuan; Gu, Ning

    2015-02-01

    Based on sharp geometry of Ni nanowires, we developed a novel high-gradient magnetic separator that was composed of a nanowires array and a uniform magnetic field. When suspension of magnetic nanoparticles (MNPs) flowed through it, the relatively large nanoparticles or clusters were removed from the suspension so that the size distribution can be improved. The separation resulted from magnetic force so that extra molecules or solvents were unnecessary to add. The performance was proved by scanned electron microscopy characterization and dynamic light scattering measurement. The improvement in magnetic colloidal dispersivity is important for the biomedical application of MNPs. Our results may also play a role in microfluidic application and nanoparticle-based detection.

  3. Magnetic-based microfluidic platform for biomolecular separation.

    Science.gov (United States)

    Ramadan, Qasem; Samper, Victor; Poenar, Daniel; Yu, Chen

    2006-06-01

    A novel microfluidic platform for manipulation of micro/nano magnetic particles was designed, fabricated and tested for applications dealing with biomolecular separation. Recently, magnetic immunomagnetic cell separation has attracted a noticeable attention due to the high selectivity of such separation methods. Strong magnetic field gradients can be developed along the entire wire, and the miniaturized size of these current-carrying conductors strongly enhances the magnetic field gradient and therefore produces large, tunable and localized magnetic forces that can be applied on magnetic particles and confine them in very small spots. Further increases in the values of the generated magnetic field gradients can be achieved by employing miniaturized ferromagnetic structures (pillars) which can be magnetized by an external magnetic field or by micro-coils on the same chip. In this study, we demonstrate magnetic beads trapping, concentration, transportation and sensing in a liquid sample under continuous flow by employing high magnetic field gradients generated by novel multi-functional magnetic micro-devices. Each individual magnetic micro-device consists of the following components: 1. Cu micro-coils array embedded in the silicon substrate with high aspect ratio conductors for efficient magnetic field generation 2. Magnetic pillar(s) made of the magnetic alloy NiCoP for magnetic field focusing and magnetic field gradient enhancement. Each pillar is magnetized by its corresponding coil 3. Integrated sensing coil for magnetic beads detection 4. Microfluidic chamber containing all the previous components. Magnetic fields of about 0.1 T and field gradients of around 300 T/cm have been achieved, which allowed to develop a magnetic force of 3 x 10(-9) N on a magnetic particle with radius of 1 mum. This force is large enough to trap/move this particle as the required force to affect such particles in a liquid sample is on the order of approximately pN. Trapping rates of up to 80% were achieved. Furthermore, different micro-coil designs were realized which allowed various movement modes and with different step-sizes. These results demonstrate that such devices incorporated within a microfluidic system can provide significantly improved spatial resolution and force magnitude for quick, efficient and highly selective magnetic trapping, separation and transportation, and as such they are an excellent solution for miniaturized mu-total analysis systems. PMID:16688574

  4. A High-Throughput SU-8Microfluidic Magnetic Bead Separator

    DEFF Research Database (Denmark)

    Bu, Minqiang; Christensen, T. B.

    2007-01-01

    We present a novel microfluidic magnetic bead separator based on SU-8 fabrication technique for high through-put applications. The experimental results show that magnetic beads can be captured at an efficiency of 91 % and 54 % at flow rates of 1 mL/min and 4 mL/min, respectively. Integration of soft magnetic elements in the chip leads to a slightly higher capturing efficiency and a more uniform distribution of captured beads over the separation chamber than the system without soft magnetic elements.

  5. Microstripes for transport and separation of magnetic particles

    DEFF Research Database (Denmark)

    Donolato, Marco; Dalslet, Bjarke Thomas

    2012-01-01

    We present a simple technique for creating an on-chip magnetic particle conveyor based on exchange-biased permalloy microstripes. The particle transportation relies on an array of stripes with a spacing smaller than their width in conjunction with a periodic sequence of four different externally applied magnetic fields. We demonstrate the controlled transportation of a large population of particles over several millimeters of distance as well as the spatial separation of two populations of magnetic particles with different magnetophoretic mobilities. The technique can be used for the controlled selective manipulation and separation of magnetically labelled species. (C) 2012 American Institute of Physics.

  6. RING-SHAPED MAGNETIC POTENTIAL BARRIERS FOR SEPARATION OF WEAKLY MAGNETIC PARTICLES

    OpenAIRE

    Gerhold, J.; Schmidt, Julien

    1984-01-01

    Weakly magnetic materials may be separated within Open Gradient Magnetic Separators using dry or wet processes. Axial-symmetric arrangments are of special interest when utilizing centrifugal forces in addition to magnetic forces. Thereby gradient fields are needed which generate mainly radially inwards directed forces. Such forces form a kind of magnetic potential barrier which cannot be transversed by magnetic particles. The necessary field distributions can be attained by means of properly ...

  7. Application of HTS bulk magnet system to the magnetic separation techniques for water purification

    International Nuclear Information System (INIS)

    We have investigated the application of the HTS bulk magnets to the magnetic separation techniques for the waste water drained from the university laboratories. The study has been conducted in comparison with the electromagnets, and the cryo-cooled superconducting solenoid magnet. A superconducting bulk magnet has the highest value of the trapped magnetic fields at the centre of the sample surface, showing a sharp gradient of the magnetic field on the surface. Magnetic force acting on magnetic particles in magnetic fields is given by the product of a magnetization of particles and a gradient of magnetic field. The HTS bulk is superior to a solenoid magnet which has a poor gradient in magnetic fields in a bore. The separation ratios of ferrite precipitates in the waste slurry were estimated by means of the high gradient magnetic separation method which requires iron filters in the water channel and open gradient magnetic separation without any filters. The magnetic separation using HTS bulk magnet is substantially effective for the practical water purification

  8. Analytical methods for separating and isolating magnetic nanoparticles.

    Science.gov (United States)

    Stephens, Jason R; Beveridge, Jacob S; Williams, Mary Elizabeth

    2012-03-14

    Despite the large body of literature describing the synthesis of magnetic nanoparticles, few analytical tools are commonly used for their purification and analysis. Due to their unique physical and chemical properties, magnetic nanoparticles are appealing candidates for biomedical applications and analytical separations. Yet in the absence of methods for assessing and assuring their purity, the ultimate use of magnetic particles and heterostructures is likely to be limited. In this review, we summarize the separation techniques that have been initially used for this purpose. For magnetic nanoparticles, it is the use of an applied magnetic flux or field gradient that enables separations. Flow based techniques are combined with applied magnetic fields to give methods such as magnetic field flow fractionation and high gradient magnetic separation. Additional techniques have been explored for manipulating particles in microfluidic channels and in mesoporous membranes. Further development of these and new analytical tools for separation and analysis of colloidal particles is critically important to enable the practical use of these, particularly for medicinal purposes. PMID:22306911

  9. Electron spin separation without magnetic field

    International Nuclear Information System (INIS)

    A nanodevice capable of separating spins of two electrons confined in a quantum dot formed in a gated semiconductor nanowire is proposed. Two electrons confined initially in a single quantum dot in the singlet state are transformed into the system of two electrons confined in two spatially separated quantum dots with opposite spins. In order to separate the electrons' spins we exploit transitions between the singlet and the triplet state, which are induced by resonantly oscillating Rashba spin–orbit coupling strength. The proposed device is all electrically controlled and the electron spin separation can be realized within tens of picoseconds. The results are supported by solving numerically the quasi-one-dimensional time-dependent Schroedinger equation for two electrons, where the electron–electron correlations are taken into account in the exact manner. (paper)

  10. Electron spin separation without magnetic field.

    Science.gov (United States)

    Paw?owski, J; Szumniak, P; Skubis, A; Bednarek, S

    2014-08-27

    A nanodevice capable of separating spins of two electrons confined in a quantum dot formed in a gated semiconductor nanowire is proposed. Two electrons confined initially in a single quantum dot in the singlet state are transformed into the system of two electrons confined in two spatially separated quantum dots with opposite spins. In order to separate the electrons' spins we exploit transitions between the singlet and the triplet state, which are induced by resonantly oscillating Rashba spin-orbit coupling strength. The proposed device is all electrically controlled and the electron spin separation can be realized within tens of picoseconds. The results are supported by solving numerically the quasi-one-dimensional time-dependent Schroedinger equation for two electrons, where the electron-electron correlations are taken into account in the exact manner. PMID:25106038

  11. MAGNETITE RECOVERY IN COAL WASHING BY HIGH GRADIENT MAGNETIC SEPARATION

    Science.gov (United States)

    The report describes a demonstration of the successful recovery of magnetite from mixtures of magnetite and coal, like those found in a coal-washing circuit, by High Gradient Magnetic Separation. The demonstration was part of a research program at Francis Bitter National Magnet L...

  12. Study on magnetic separation system using high Tc superconducting bulk magnets for water purification technique

    International Nuclear Information System (INIS)

    The application of superconducting bulk magnets to the magnetic separation techniques has been investigated for the Mn-bearing waste water drained from the university laboratories. The research has been conducted in comparison with the electromagnets, and the cryo-cooled superconducting solenoid magnet. The separation ratios of ferrite precipitates including Mn element in the waste slurry were estimated by means of the high gradient magnetic separation method with ferromagnetic iron filters in the water channel and open gradient magnetic separation without them. As the magnetic force acting on the particles is given by the product of a magnetization of particles and a gradient of magnetic field, and a superconducting bulk magnet shows a sharp gradient of the magnetic field on the surface, the performances of the bulk magnet system were almost equivalent to those of the superconducting solenoid magnet with wide bore with respect to the magnetic separation ratios. The separation ratios for Mn have reached over 80 % for HGMS and 10 % for OGMS under the flow rates less than 3 liter/min.

  13. Process for magnetic separation of metals from aqueous media

    International Nuclear Information System (INIS)

    Paramagnetic metals are separated from aqueous media containing them in low concentration by first fixing the metals on bacterial, yeast or other cells so as to render the cells magnetic, and then separating the cells from the media by a high gradient magnetic separation technique. The metal and the cells are contacted in the presence of a compound which is converted by the cells into a product which interacts with the metal and causes it to become bound to the cells. The process is particularly useful for removing low concentrations of highly toxic or radioactive metals, e.g. uranium, from industrial effluents containing them. (author)

  14. In Situ Magnetic Separation for Extracellular Protein Production

    DEFF Research Database (Denmark)

    Kappler, T.; Cerff, Martin

    2009-01-01

    A new approach for in situ product removal from bioreactors is presented in which high-gradient magnetic separation is used. This separation process was used for the adsorptive removal of proteases secreted by Bacillus licheniformis. Small, non-porous bacitracin linked magnetic adsorbents were employed directly in the broth during the fermentation, followed by in situ magnetic separation, Proof of the concept was first demonstrated in shake flask culture, then scaled up and applied during a fed batch cultivation ill a 3.7 L bioreactor. It could be demonstrated that growth of B. licheniformis was not influenced by the in situ product removal step. Protease production also remained the same after the separation step. Furthermore, degradation of the protease, which followed first order kinetics, was reduced by using the method. Using a theoretical modeling approach, we Could show that protease yield in total was enhanced by using in situ magnetic separation. The process described here is a promising technique toimprove overall yield in No production processes which are often limited due to weak downstream operations, Potential limitations encountered during a bioprocess can be overcome such as product inhibition or degradation. We also discuss the key points where research is needed to implement in situ magnetic separation in industrial production.

  15. Magnetic precipitate separation for Ni plating waste liquid using HTS bulk magnets

    International Nuclear Information System (INIS)

    Highlights: ? The magnetic separation was operated for recycling the electroless plating waste. ? The HTS bulk magnet effectively attracted the ferromagnetic precipitates with Ni. ? The separation ratios over 90% were reported under flow rates up to 1.35 L/min. -- Abstract: The magnetic separation experiment for recycling the nickel-bearing precipitates in the waste liquid from the electroless plating processes has been practically conducted under the high gradient magnetic separation technique with use of the face-to-face HTS bulk magnet system. A couple of facing magnetic poles containing Sm123 bulk superconductors were activated through the pulsed field magnetization process to 1.86 T at 38 K and 2.00 T at 37 K, respectively. The weakly magnetized metallic precipitates of Ni crystals and Ni–P compounds deposited from the waste solution after heating it and pH controlling. The high gradient magnetic separation technique was employed with the separation channels filled with the stainless steel balls with dimension of 1 and 3 mm in diameter, which periodically moved between and out of the facing magnetic poles. The Ni-bearing precipitates were effectively attracted to the magnetized ferromagnetic balls. We have succeeded in obtaining the separation ratios over 90% under the flow rates less than 1.35 L/min

  16. Microfabricated magnetic sifter for high-throughput and high-gradient magnetic separation

    Science.gov (United States)

    Earhart, Christopher M.; Wilson, Robert J.; White, Robert L.; Pourmand, Nader; Wang, Shan X.

    2009-05-01

    A microfabricated magnetic sifter has been designed and fabricated for applications in biological sample preparation. The device enables high-throughput, high-gradient magnetic separation of magnetic nanoparticles by utilizing columnar fluid flow through a dense array (˜5000/mm 2) of micropatterned slots in a magnetically soft membrane. The potential of the sifter for separation of magnetic nanoparticles conjugated with capture antibodies is demonstrated through quantitative separation experiments with CD138-labeled MACS nanoparticles. Capture efficiencies ranging from 28% to 37% and elution efficiencies greater than 73% were measured for a single pass through the sifter.

  17. Microfabricated magnetic sifter for high-throughput and high-gradient magnetic separation

    International Nuclear Information System (INIS)

    A microfabricated magnetic sifter has been designed and fabricated for applications in biological sample preparation. The device enables high-throughput, high-gradient magnetic separation of magnetic nanoparticles by utilizing columnar fluid flow through a dense array (?5000/mm2) of micropatterned slots in a magnetically soft membrane. The potential of the sifter for separation of magnetic nanoparticles conjugated with capture antibodies is demonstrated through quantitative separation experiments with CD138-labeled MACS nanoparticles. Capture efficiencies ranging from 28% to 37% and elution efficiencies greater than 73% were measured for a single pass through the sifter.

  18. Use of high gradient magnetic separation for actinide application

    International Nuclear Information System (INIS)

    Decontamination of materials such as soils or waste water that contain radioactive isotopes, heavy metals, or hazardous components is a subject of great interest. Magnetic separation is a physical separation process that segregates materials on the basis of magnetic susceptibility. Because the process relies on physical properties, separations can be achieved while producing a minimum of secondary waste. Most traditional physical separation processes effectively treat particles larger than 70 microns. In many situations, the radioactive contaminants are found concentrated in the fine particle size fraction of less than 20 microns. For effective decontamination of the fine particle size fraction most current operations resort to chemical dissolution methods for treatment. High gradient magnetic separation (HGMS) is able to effectively treat particles from 90 to ?0.1 micron in diameter. The technology is currently used on the 60 ton per hour scale in the kaolin clay industry. When the field gradient is of sufficiently high intensity, paramagnetic particles can be physically captured and separated from extraneous nonmagnetic material. Because all actinide compounds are paramagnetic, magnetic separation of actinide containing mixtures is feasible. The advent of reliable superconducting magnets also makes magnetic separation of weakly paramagnetic species attractive. HGMS work at Los Alamos National Laboratory (LANL) is being developed for soil remediation, waste water treatment and treatment of actinide chemical processing residues. LANL and Lockheed Environmental Systems and Technologies Company (LESAT) have worked on a co-operative research and development agreement (CRADA) to develop HGMS for radioactive soil decontamination. The program is designed to transfer HGMS from the laboratory and other industries for the commercial treatment of radioactive contaminated materials. 9 refs., 2 figs., 2 tabs

  19. Low field orientation magnetic separation methods for magnetotactic bacteria

    International Nuclear Information System (INIS)

    Microbial biomineralisation of iron often results in a biomass that is magnetic and can be separated from water systems by the application of a magnetic field. Magnetotactic bacteria form magnetic membrane bound crystals within their structure, generally of magnetite. In nature, this enables magnetotactic bacteria to orientate themselves with respect to the local geomagnetic field. The bacteria then migrate with flagellar driven motion towards their preferred environment. This property has been harnessed to produce a process in which metal loaded magnetotactic bacteria can be recovered from a waste stream. This process is known as orientation magnetic separation. Several methods exist which permit the unique magnetic properties of individual magnetotactic bacteria to be studied, such as U-turn analysis, transmission electron microscopy and single wire cell studies. In this work an extension of U-turn analysis was developed. The bacteria were rendered non-motile by the addition of specific metal ions and the resulting 'flip time' which occurs during a field reversal enabled the magnetic moment of individual bacteria to be determined. This method proved to be much faster and more accurate than previous methods. For a successful process to be developed, large scale culturing of magnetotactic bacteria is required Experiments showed that culture vessel geometry was an important factor for high-density growth. Despite intensive studies reproducible culturing at volumes exceies reproducible culturing at volumes exceeding one litre was not achieved. This work showed that numerous metal ions rendered magnetotactic bacteria non-motile at concentrations below 10 ppm. Sequential adaptation raised typical levels to in excess of 100 ppm for a number of ions. such as zinc and tin. However, specific ions. such as copper or nickel, remained motility inhibiting at lower concentrations. To achieve separation using orientation magnetic separation, motile, field susceptible MTB are required. Despite successful adaptation, the range of motility inhibiting ions is such that MTB cannot be envisaged for general wastewater applications. Radionucleide studies were undertaken targeting a niche application where this metal ion restriction would not apply. Liquid scintillation and ?-ray counting measurements indicated that magnetotactic bacteria accumulate high levels of both plutonium and mercury. A number of both static and flow recovery separators for magnetotactic bacteria were developed. Statistical models predicting the behaviour of these separators were compared to measured results. These comparisons highlighted the problems of 'wash off' of accumulated bacteria in separators where flow was present. The most successful of the flow recovery designs - the channel separator - was then tested using a simulated effluent that contained plutonium. The results confirmed both previous radioisotope uptake studies and separator test results. The channel separator design was enhanced by the introduction of wire arrays into the separation chamber. Orientation magnetic separation in these hybrid-type separators was used to accumulate the biomass and the magnetic gradients generated by the wire arrays to retain the bacteria on the separator walls. These separators achieved increases in efficiency of up to 300% compared with the channel separator. In summary, this thesis describes a successful separation process for the recovery of motile MTB. However, to apply this separator approach to the suggested radioisotope application would require successful large scale culturing. (author)

  20. Magnetic isotope effect and isotope separation in ''microreactors''

    International Nuclear Information System (INIS)

    The possibility of increasing the effectiveness isotope separation in reversible radical photochemical reactions, is investigated. The effectiveness of isotope separation in the radical pair with a limited diffusion dynamics in a limited volume - ''microreactor'', is calculated. The separation effectiveness under such conditions increases considerably. Quantitative ratios between the rate constant of radical transformation, diffusion coefficient and ''microreactor'' dimensions providing the most effective enrichment, are found. The conclusion is made that reacting under conditions of limited diffusion dynamics of radical pairs opens new perspectives in isotope separation on the basis of magnetic isotopic effect

  1. Bench-scale magnetic separation of Department of Energy wastes

    International Nuclear Information System (INIS)

    Criteria were developed for selection of candidate wastes for testing magnetic separation of uranium and/or other paramagnetic materials. A survey of Department of Energy (DOE) hazardous wastes was conducted to determine good candidates for bench-scale magnetic separation tests. Representatives of 21 DOE sites were contacted, and 11 materials were identified as potential candidates for magnetic separation. To date, seven samples have been obtained and tested for separability of uranium with a bench-scale magnetic assaying device. The samples tested have been obtained from the K-1401B and K-1401C ponds in Oak Ridge, Tennessee; from waste piles in Maywood, New Jersey; from North and South Ponds in Richland, Washington; and from magnesium fluoride drums in Fernald, Ohio. The magnetic device utilized in these tests can be used in an open-gradient mode with dry particulate or liquid-suspended materials. Uranium separation from magnesium fluoride has shown exceptionally good performance in both open- and high-gradient modes and could be an important application of the technology

  2. Iso-geometric shape optimization of magnetic density separators

    DEFF Research Database (Denmark)

    Dang Manh, Nguyen; Evgrafov, Anton

    2014-01-01

    Purpose The waste recycling industry increasingly relies on magnetic density separators. These devices generate an upward magnetic force in ferro-fluids allowing to separate the immersed particles according to their mass density. Recently, a new separator design has been proposed that significantly reduces the required amount of permanent magnet material. The purpose of this paper is to alleviate the undesired end-effects in this design by altering the shape of the ferromagnetic covers of the individual poles. Design/methodology/approach The paper represents the shape of the ferromagnetic pole covers with B-splines and defines a cost functional that measures the non-uniformity of the magnetic field in an area above the poles. The authors apply an iso-geometric shape optimization procedure, which allows us to accurately represent, analyze and optimize the geometry using only a few design variables. The design problem is regularized by imposing constraints that enforce the convexity of the pole cover shapes and is solved by a non-linear optimization procedure. The paper validates the implementation of the algorithm using a simplified variant of the design problem with a known analytical solution. The algorithm is subsequently applied to the problem posed. Findings The shape optimization attains its target and yields pole cover shapes that give rise to a magnetic field that is uniform over a larger domain. Research limitations/implications This increased magnetic field uniformity is obtained at the cost of a pole cover shape that differs per pole. This limitation has negligible impact on the manufacturing of the separator. The new pole cover shapes therefore lead to improved performance of the density separation. Practical implications Due to the larger uniformity the generated field, these shapes should enable larger amounts of waste to be processed than the previous design. Originality/value This paper treats the shapes optimization of magnetic density separators systematically and presents new shapes for the ferromagnetic poles covers.

  3. Waste remediation using in situ magnetically assisted chemical separation

    International Nuclear Information System (INIS)

    The magnetically assisted chemical separation process (MACS) combines the selective and efficient separation afforded by chemical sorption with the magnetic recovery of ferromagnetic particles. This process is being developed for treating the underground storage tanks at Hanford. These waste streams contain cesium, strontium, and transuranics (TRU) that must be removed before this waste can be disposed of as grout. The separation process uses magnetic particles coated with either (1) a selective ion exchange material or an organic extractant containing solvent (for cesium and strontium removal) or (2) solvents for selective separation of TRU elements (e.g., TRUEX process). These coatings, by their chemical nature, selectively separate the contaminants onto the particles, which can then be recovered from the tank using a magnet. Once the particles are removed, the contaminants can either be left on the loaded particles and added to the glass feed slurry or stripped into a small volume of solution so that the extracting particles can be reused. The status of chemistry and separation process is discussed in this paper

  4. Inverted Linear Halbach Array for Separation of Magnetic Nanoparticles.

    Science.gov (United States)

    Ijiri, Y; Poudel, C; Williams, P S; Moore, L R; Orita, T; Zborowski, M

    2013-07-01

    A linear array of Nd-Fe-B magnets has been designed and constructed in an inverted Halbach configuration for use in separating magnetic nanoparticles. The array provides a large region of relatively low magnetic field, yet high magnetic field gradient in agreement with finite element modeling calculations. The magnet assembly has been combined with a flow channel for magnetic nanoparticle suspensions, such that for an appropriate distance away from the assembly, nanoparticles of higher moment aggregate and accumulate against the channel wall, with lower moment nanoparticles flowing unaffected. The device is demonstrated for iron oxide nanoparticles with diameters of ~ 5 and 20 nm. In comparison to other approaches, the inverted Halbach array is more amenable to modeling and to scaling up to preparative quantities of particles. PMID:25382864

  5. Separation of actinide-made transurania by a gas-filled magnetic separator

    International Nuclear Information System (INIS)

    The performance of the gas-filled magnetic separator HECK at the UNI-LAC at GSI Darmstadt is described. The system consists of a 30 -dipole magnet and a quadrupole doublet of wide aperture. The separator is operated with helium at pressures between (0.1-1) hPa. It is used to investigate heavy ion induced fusion products in-flight. The recoils emerging from a thin target are separated with high efficiency of (10-50)%. The suppression factor of primary beam particles and transfer products is (1015) and (103), respectively. In this application of a gas-filled separator to synthesize transuranium elements using 238U-targets, isotopes of the elements fermium and nobelium were identified in irradiations with 16O- and 20Ne-beams. (orig.)

  6. On heteroclinic separators of magnetic fields in electrically conducting fluids

    CERN Document Server

    Grines, V; Pochinka, O; Zhuzhoma, E

    2014-01-01

    In this paper we partly solve the problem of existence of separators of a magnetic field in plasma. We single out in plasma a 3-body with a boundary in which the movement of plasma is of special kind which we call an (a-d)-motion. We prove that if the body is the 3-annulus or the "fat" orientable surface with two holes the magnetic field necessarily have a heteroclinic separator. The statement of the problem and the suggested method for its solution lead to some theoretical problems from Dynamical Systems Theory which are of interest of their own.

  7. Process to remove actinides from soil using magnetic separation

    Science.gov (United States)

    Avens, Larry R. (Los Alamos, NM); Hill, Dallas D. (Los Alamos, NM); Prenger, F. Coyne (Los Alamos, NM); Stewart, Walter F. (Las Cruces, NM); Tolt, Thomas L. (Los Alamos, NM); Worl, Laura A. (Los Alamos, NM)

    1996-01-01

    A process of separating actinide-containing components from an admixture including forming a slurry including actinide-containing components within an admixture, said slurry including a dispersion-promoting surfactant, adjusting the pH of the slurry to within a desired range, and, passing said slurry through a pretreated matrix material, said matrix material adapted to generate high magnetic field gradients upon the application of a strong magnetic field exceeding about 0.1 Tesla whereupon a portion of said actinide-containing components are separated from said slurry and remain adhered upon said matrix material is provided.

  8. Ultrasound imaging for quantitative evaluation of magnetic density separation:

    OpenAIRE

    Sanaee, S.A.

    2013-01-01

    This thesis is dedicated to an investigation of the potential and technological possibilities of an inline ultrasound system as a quality control system for wet recycling of solid waste. The main targeted recycling technology is magnetic density separation (MDS), a novel technique that was investigated and technologically matured in a project running in parallel to this work. In MDS, the easily magnetisable ferrofluid is used as the separation medium to sort different materials based on their...

  9. Magnetic driven separation techniques - DNA isolation from probiotic food samples.

    Czech Academy of Sciences Publication Activity Database

    Trachtová, S.; Španová, A.; Prettl, Z.; Horák, Daniel; Rittich, B.

    Wroclaw : Institute of Immunology and Experimental Therapy Polish Academy of Science, 2013 - (Gamian, A.; Górska-Fraczek, S.). s. 27 ISBN 978-83-928488-3-7. [Polish-Czech Probiotics Conference /1./ - Microbiology and Immunology of Mucosa, Probiotics Conference 2013. 28.05.2013-31.05.2013, Kudowa Zdrój] R&D Projects: GA ?R GAP206/12/0381 Institutional support: RVO:61389013 Keywords : magnetic * DNA * separation Subject RIV: CB - Analytical Chemistry, Separation

  10. Loss separation for dynamic hysteresis in magnetic thin films

    OpenAIRE

    Colaiori, Francesca; Durin, Gianfranco; Zapperi, Stefano

    2006-01-01

    We develop a theory for dynamic hysteresis in ferromagnetic thin films, on the basis of the phenomenological principle of loss separation. We observe that, remarkably, the theory of loss separation, originally derived for bulk metallic materials, is applicable to disordered magnetic systems under fairly general conditions regardless of the particular damping mechanism. We confirm our theory both by numerical simulations of a driven random--field Ising model, and by re--exami...

  11. Magnetic field analysis of high gradient magnetic separator via finite element analysis

    Science.gov (United States)

    Baik, S. K.; Ha, D. W.; Ko, R. K.; Kwon, J. M.

    2012-10-01

    High Gradient Magnetic Separator (HGMS) uses matrix to make high magnetic field gradient so that ferro- or para-magnetic particles can be attracted to them by high magnetic force. The magnetic force generated by the field gradient is several thousand times larger than that by the magnetic flux density alone. So the HGMS shows excellent performance compared with other magnetic separators. These matrices are usually composed of stainless wires having high magnetization characteristics. This paper deals with superconducting HGMS which is aimed for purifying wastewater by using stainless steel matrix. Background magnetic field up to 6 T is generated by a superconducting solenoid and the stainless steel matrices are arranged inside of the solenoid. In order to calculate magnetic forces exerting on magnetic particles in wastewater, it is important to calculate magnetic field and magnetic field gradient those are proportional to the magnetic force acting on the particle. So we presents magnetic field distribution analysis result and estimates how many times of magnetic force will act on a particle when the matrix are arranged or not. Magnetic field is calculated in 3 dimensions by using Finite Element Method (FEM) and also compared with results obtained from 2 dimensional analysis.

  12. Dendrimer-coated magnetic particles for radionuclide separation

    International Nuclear Information System (INIS)

    Magnetic particles were synthesised for radionuclide removal from nuclear wastes by magnetic separation. Dendrimers with terminal amino groups attached to the particle surface were used to bind chelating groups for lanthanides and actinides. This led to a 50-400-fold increase of the distribution coefficients for europium and americium in comparison to the reference particles without the dendrimers. Back-extraction studies have demonstrated the possibility of multiple particle recycling

  13. Microstripes for transport and separation of magnetic particles

    OpenAIRE

    Donolato, Marco; Dalslet, Bjarke Thomas; Hansen, Mikkel Fougt

    2012-01-01

    We present a simple technique for creating an on-chip magnetic particle conveyor based on exchange-biased permalloy microstripes. The particle transportation relies on an array of stripes with a spacing smaller than their width in conjunction with a periodic sequence of four different externally applied magnetic fields. We demonstrate the controlled transportation of a large population of particles over several millimeters of distance as well as the spatial separation of two populations of ma...

  14. Ferritin as a label for high-gradient magnetic separation.

    OpenAIRE

    Owen, C. S.; Lindsay, J. G.

    1983-01-01

    In three model systems, particles the size of cells or smaller have been surface labeled with ferritin to make them slightly paramagnetic, by virtue of the iron in the ferritin. In each case it was possible to show that labeled particles could be magnetically removed from a flowing suspension by the high-gradient magnetic separation (HGMS) technique. The first system of particles consisted of small (1 micron) carboxylate-modified latex spheres to which ferritin was covalently bound to create ...

  15. The study on optimization issues for magnetic separation by magnetic chromatography

    International Nuclear Information System (INIS)

    The magnetic chromatography is a very useful system for an ion and/or fine magnetic particle separation because it has strong magnetic field gradients even in a very narrow flow channel. We have not only developed the magnetic chromatography system to separate the fine particles and ions, but also the numerical analysis code based on the fluid dynamics and electromagnetism to investigate the separating characteristics and to optimize design of magnetic column. In this study, the simple experiments using a superconducting magnet with a large room-temperature-bore and a micro-scale magnetic column consisting of ferromagnetic wires were carried out to understand the ions separation. The cobalt chloride (CoCl2) and the nickel sulfate (NiSO4) were used as ions, and the magnetic field and length of magnetic column were used as a parameter in an experiment and an analysis. It can be expected that the ion mobility of a single and complex are quite different, and the ability of the separation will be improved by increasing the column length without external magnetic field.

  16. An experimental investigation of the effect of preliminary magnetization in magnetic separation

    International Nuclear Information System (INIS)

    The effects of preliminary magnetization on the high-gradient magnetic separation of hematite and uranium-gold leach residues were studied. It is shown that the pre-magnetization of anti-ferromagnetic hematite can enhance the recovery of iron and the grade of the magnetic product. The effect of pre-magnetization was found to increase with decreasing particle size, the recovery from the fraction -12 ?m increasing by 11% and the grade of the magnetic concentrate by 30%. The pre-magnetization of paramagnetic uranium-gold leach residues, however, reduced the recovery of uranium. It is suggested that the behaviour of a mineral with an ordered magnetic structure is related to magnetic viscosity. The capital and operating costs of the magnet required for pre-magnetization are assessed. (orig.)

  17. RESEARCH ON MAGNETIC SORTING AND SEPARATION TECHNIQUES FOR MATERIALS USED IN AUTOMOBILE CONSTRUCTION

    OpenAIRE

    Amza, Gheorghe; Dobrota, Dan; Apostolescu, Zoia

    2013-01-01

    The main sorting process are: separation based on density; on magnetic properties; on melting properties; on friction and piece shape; on interface properties, on chemical composition etc. This paper shows some contributions regarding magnetic separation. Magnetic separation based on permanent magnets are using to treat materials smaller than 50 mm, high intensity magnetic separators are used to recover magnetic and ferro-silicon, for removal of iron aluminium, a complex material consisting o...

  18. Models of particle capture in high gradient magnetic separation

    Science.gov (United States)

    Eisentraeger, Almut; Griffiths, Ian; Vella, Dominic

    2013-11-01

    High gradient magnetic separation is an efficient way to remove magnetic and paramagnetic particles, such as heavy metals, from waste water. As the water flows through a mesh of magnetized steel wool, high magnetic gradients around the wires attract and capture the particles. We model such a system by considering a single point dipole travelling through a periodic array of magnetized cylinders. We show that there is a critical Mason number (dimensionless flow velocity) below which the particle is captured independent of its initial position. Above this threshold, particle capture is only partially successful and depends on the particle's initial position. We determine the relationship between the critical Mason number and geometry using numerical and asymptotical calculations. To develop these ideas further, we also discuss briefly the aggregation of particles into chains.

  19. Feasibility study of iron mineral separation from red mud by high gradient superconducting magnetic separation

    International Nuclear Information System (INIS)

    Research highlights: ? Red mud residues (RM) were disposed in alumina production. ? Utilization of Red mud residues was affected by its iron content. ? Superconducting magnetic separation (HGSMS) was used in iron separation from RM. ? RM with high and low iron contents were separated in HGSMS. - Abstract: The disposal of bayer red mud tailings now seriously threats the environment safety. Reduction and recycling of red mud is now an urgent work in aluminum industry. High gradient superconducting magnetic separation (HGSMS) system was applied to separate the extreme fine RM particles (<100 ?m) into high iron content part and low iron content part. Two sorts of RM were fed in the HGSMS. The iron oxide contents in concentrates were about 65% and 45% when RM 1 and RM 2 were fed respectively. Meanwhile, the residues contained 52.0% or 14.1% iron oxide in residues after eight separation stages when RM 1 and RM 2 were fed respectively. The mass recovery of iron concentrates was about 10% after once separation process regardless of RM 1 or RM 2 was fed. Extreme fine particles (<10 ?m) could be captured in the HGSMS. Intergrowth of Fe and other elements is disadvantages for iron mineral separation from RM by HGSMS. Some improvement should be studied to enhance the efficiency of iron separation. It is possible for HGSMS to separate RM into high iron content part and low iron content part, the former part could be used in iron-making furnace and the later part could benace and the later part could be recycling to sintering process for alumina production or used as construction material.

  20. Phase Separation, Magnetism and Superconductivity in Rutheno-Cuprates

    OpenAIRE

    Lorenz, B.; Xue, Y. Y.; Chu, C. W.

    2002-01-01

    The properties of the superconducting ferromagnets RuSr2(Gd/Eu)Cu2O8 and RuSr2(Ln/Ce)2Cu2O10 are reviewed. The problem of coexistence and competition between magnetic and superconducting states is discussed. A model of phase separation into ferromagnetic and anti-ferromagnetic structures is proposed.

  1. Separation of the Magnetic Field into External and Internal Parts

    DEFF Research Database (Denmark)

    Olsen, Nils; Glassmeier, K.-H.

    2010-01-01

    The magnetic field of a planet or a planetary moon contains contributions from a variety of sources in the environment of the body (external sources) and its interior (internal sources). This chapter describes different methods that have been developed for the separation of external and internal source contributions, and their application to selected planets and one of Jupiter’s moons, Ganymede.

  2. High-frequency magnet for separating beams in colliders

    International Nuclear Information System (INIS)

    A prototype 130 kHz ferrite-cored magnet designed for separating bunched beams of protons and antiprotons in a high-energy collider has been built and tested in vacuum up to 620 gauss. The main problems are the removal of the power dissipated in the ferrite and the withstand voltage of the coil in relation to the yoke

  3. HIGH-FREQUENCY MAGNET FOR SEPARATING BEAMS IN COLLIDERS

    OpenAIRE

    Baconnier, Y.; Dupin, J.; Guinand, R.; Kissler, K.; Middelkoop, W.; Paillard, G.; Warman, A.; Zanasco, J. -p

    1984-01-01

    A prototype 130 kHz ferrite-cored magnet designed for separating bunched beams of protons and antiprotons in a high-energy collider has been built and tested in vacuum up to 620 gauss. The main problems are the removal of the power dissipated in the ferrite and the withstand voltage of the coil in relation to the yoke.

  4. TREATMENT OF COMBINED SEWER OVERFLOWS BY HIGH GRADIENT MAGNETIC SEPARATION

    Science.gov (United States)

    Seeded water treatment by high gradient magnetic separation techniques was carried out on combined storm overflows and raw sewage influents. Both bench-type and continuous pilot plant tests were performed to evaluate the effectiveness of the process in purifying waste waters. Cri...

  5. Magnetic Separations with Magnetite: Theory, Operation, and Limitations

    Energy Technology Data Exchange (ETDEWEB)

    G. B. Cotten

    2000-08-01

    This dissertation documents the theory development and experimental plan followed to describe how a magnetite-based column under the influence of an external magnetic field functions as a magnetic separator. Theoretical simulations predict that weekly paramagnetic particles in the sub-micron range can be magnetically separated while diamagnetic particles as large as 2 microns in diameter may pass. Magnetite-based columns were evaluated as magnetically-controllable enhanced filtration devices. There was no evidence of enhanced filtration for diamagnetic particles by the magnetite-based bed. Magnetite-based magnetic separators have proven to be effective in specific laboratory experiments, indicating a potential feasibility for scale-up operations. Column media-filter type filtration effects indicate a magnetite-based column would not be suitable for treatment of a waste stream with a high diamagnetic solids content or high volume throughput requirements. Specific applications requiring removal of sub-micron para- or ferromagnetic particles under batch or Stokes flow conditions would be most applicable.

  6. Magnetic separation using high-T sub c superconductors

    CERN Document Server

    Bolt, L

    2001-01-01

    sensitivity of the high-T sub c material to magnetic fields. Finite elements modelling of the system has provided the framework for the quantitative analysis of the magnetic field distributions on the coil windings and the optimisation of the system configuration. The performance of the separator has been tested at 77 K with liquid nitrogen at atmospheric pressure, and at a temperature approx = 67 K by pumping liquid nitrogen at a pressure around 100 Torr. The highest field obtained in the air gap at 67 K was of 340 mT. Magnetic separators with an iron circuit have been in operation for many years in mineral industry, and there appear to be an opportunity of building machines with high-T sub c coils or retrofitting existing machines with high-T sub c coils to run them closer to saturation in a cheap and effective way. Superconductivity has found in magnetic separation one of its major industrial applications second only to magnetic resonance imaging. Low-T sub c superconducting coils have been employed in Hig...

  7. Magnetic Separations with Magnetite: Theory, Operation, and Limitations

    International Nuclear Information System (INIS)

    This dissertation documents the theory development and experimental plan followed to describe how a magnetite-based column under the influence of an external magnetic field functions as a magnetic separator. Theoretical simulations predict that weekly paramagnetic particles in the sub-micron range can be magnetically separated while diamagnetic particles as large as 2 microns in diameter may pass. Magnetite-based columns were evaluated as magnetically-controllable enhanced filtration devices. There was no evidence of enhanced filtration for diamagnetic particles by the magnetite-based bed. Magnetite-based magnetic separators have proven to be effective in specific laboratory experiments, indicating a potential feasibility for scale-up operations. Column media-filter type filtration effects indicate a magnetite-based column would not be suitable for treatment of a waste stream with a high diamagnetic solids content or high volume throughput requirements. Specific applications requiring removal of sub-micron para- or ferromagnetic particles under batch or Stokes flow conditions would be most applicable

  8. Magnetic precipitate separation for Ni plating waste liquid using HTS bulk magnets

    Science.gov (United States)

    Oka, T.; Kimura, T.; Mimura, D.; Fukazawa, H.; Fukui, S.; Ogawa, J.; Sato, T.; Ooizumi, M.; Yokoyama, K.; Tsujimura, M.; Terasawa, T.

    2013-01-01

    The magnetic separation experiment for recycling the nickel-bearing precipitates in the waste liquid from the electroless plating processes has been practically conducted under the high gradient magnetic separation technique with use of the face-to-face HTS bulk magnet system. A couple of facing magnetic poles containing Sm123 bulk superconductors were activated through the pulsed field magnetization process to 1.86 T at 38 K and 2.00 T at 37 K, respectively. The weakly magnetized metallic precipitates of Ni crystals and Ni-P compounds deposited from the waste solution after heating it and pH controlling. The high gradient magnetic separation technique was employed with the separation channels filled with the stainless steel balls with dimension of 1 and 3 mm in diameter, which periodically moved between and out of the facing magnetic poles. The Ni-bearing precipitates were effectively attracted to the magnetized ferromagnetic balls. We have succeeded in obtaining the separation ratios over 90% under the flow rates less than 1.35 L/min.

  9. Particle acceleration at 3D reconnecting magnetic separators

    Science.gov (United States)

    Threlfall, James; Neukirch, Thomas; Parnell, Clare; Stevenson, Julie

    2015-04-01

    We present results of test particle orbit calculations in three different environments which model separator reconnection in three dimensions. The test particle (electron and proton) orbits are calculated using the relativistic guiding centre approximation. We investigate test particle orbits in a time-dependent (analytical) electro-magnetic field configuration [detailed in Threlfall et al. (A&A, in press); arXiv:1410.6465]. These results are also compared with orbits based upon large-scale 3D MHD simulations of both a single reconnecting magnetic separator and an observationally driven 3D model of a solar active region which contains several topological features of interest, including separators. We discuss how the test-particle orbits and the energy gain depend on the initial conditions, and how observations (for example, of solar flares) may be used to constrain model parameters.

  10. Maximizing the recovery of fine iron ore using magnetic separation

    Scientific Electronic Library Online (English)

    M, Dworzanowski.

    2012-03-01

    Full Text Available The beneficiation of fine iron ore will increase in importance in the future because most new iron ore resources will be in the form of lower grade ore deposits that will require liberation of iron ore minerals at finer sizes. Generally this fine iron ore will be benefi-ciated to produce a pelletizi [...] ng concentrate with very strict chemical and physical specifications. In addition, because of the increasing demand for iron ore there are now more opportunities to produce by-product iron ore from mining operations producing other commodities. In the past the associated iron ore minerals would report to final tailings but now there is potential value to be realised from by-product revenue. These by-product iron ore opportunities are almost all centred on producing pelletizing concentrate. Currently pelletizing concentrates are produced mainly by various combinations of flotation and magnetic separation. The selection of the beneficiation route will depend on ore mineralogy and considerations around plant capacity and final concentrate quality. The main economic iron minerals are magnetic, haematite being paramagnetic and magnetite being ferromagnetic. This, therefore, means that magnetic separation can be applied, in principle, to all fine iron-ore beneficiation plants. While flotation has a considerable capacity advantage over magnetic separation, the real advantage of magnetic separation over flotation in fine iron-ore beneficiation is that treatment of -10 µm iron ore is possible-in flotation, the feed is deslimed at 10 µm and the -10 µm stream is considered to be final tailings, even though there is often a significant amount of contained iron ore. This paper describes a study around the recovery of fine magnetite in the form of a pelletizing concentrate. The study is based on an evaluation of an iron ore by-product opportunity from an iron oxide copper-gold (IOCG) deposit. Experiments were conducted to quantify the differences in magnetic separation performance with decrease in particle size treated. A mineralogical evaluation of all the test work products was undertaken to facilitate the interpretation of the test work results. These results were then used to propose an economically viable flowsheet for maximizing fine magnetite recovery using magnetic separation.

  11. Waste water purification by magnetic separation technique using HTS bulk magnet system

    International Nuclear Information System (INIS)

    We have investigated the feasibility of strong magnetic field generators composed of the high temperature superconducting (HTS) bulk magnet systems to the magnetic separation techniques for the waste water including thin emulsion bearing the cutting oil. Two types of the strong field generators were prepared by the face-to-face HTS bulk magnet systems, which emit the magnetic field density of 1 and 2 T in the open spaces between the magnetic poles activated by the pulsed field magnetization and the field cooling methods, respectively. A couple of water channels containing iron balls were settled in the strong field to trap the magnetized flocks in the waste water. The separation ratios of flocks containing 200 ppm magnetite powder were evaluated with respect to the flow rates of the waste water. The performances of bulk magnet system have kept showing values of around 100% until the flowing rate reached up to 18 l/min. This suggests that the magnetic separation by using bulk magnets is effective for the practical water purification systems.

  12. The electromagnetic design of a permanent magnet based separator

    International Nuclear Information System (INIS)

    The aim of this work was to design a permanent magnet based device that can selectively transport paramagnetic particles. Using specialised electromagnetic design software various arrangements of permanent magnets have been investigated. Each test geometry had to be constructively simple and able to produce highly non-uniform magnetic fields before being considered further in any more detail. The main parameter to indicate that the test geometry might be a suitable device has been ascribed to the ratio ? between the highest (ON) and lowest (OFF) magnetic fields that were measured. A linear arrangement of permanent magnets has been considered first. This device produced a ratio ? ? 2. Further, the cylindrical and the tubular arrangements may be considered as substantial improvements over the first geometry. The OFF magnetic fields have been substantially reduced by the method of magnetic shielding. Intensive research and modelling has been spent on addressing the problem of finding the optimal geometry for such arrangements. An experimental system has been also built, and the experimental values were compared against the theory. However, the results produced evidence that the manufacturing of any improved geometry (an estimated ? ? 100) in this direction might be very difficult, for the tolerances involved were very strict. The disk arrangement was the latest device to be investigated. Particularly, a magnetic dipole model developed earlier for the ring arrangemloped earlier for the ring arrangement suggested the way in which to arrange the magnets in the ON position. Moreover, the use of the magnetic symmetry of the device forced the OFF magnetic fields to negligible values. Detailed computer simulations of the dynamics of the particles in the applied magnetic field of the tubular and disk arrangements have been earned out. The adopted models could show realistic phenomena, e.g. particle clustering, chaining, block movement, etc. The separation efficiency proved to be nearly 100%. For the disk arrangement the minimum paramagnetic susceptibility of the particle that could be transported has been ? ? 10-4. In addition, the particle radii had little influence on the functioning of this magnetic separation device. (author)

  13. Magnetic separation as a plutonium residue enrichment process

    International Nuclear Information System (INIS)

    Several plutonium contaminated residues have been subjected to Open Gradient Magnetic Separation (OGMS) on an experimental scale. OGMS experiments on graphite and bomb reduction residues resulted in a plutonium rich fraction and a plutonium lean fraction. Values for the bulk quantity rejected to the lean fraction varied between about 20% to 85% of the feed bulk. The plutonium content of the lean fraction can be reduced from about 2% in the feed to the 0.1% to 0.5% range dependent on the portion of the feed rejected to this lean fraction. These values are low enough in plutonium to meet economic discard limits and be considered for direct discard. Magnetic separation of pyrochemical salts gave less favorable results. While a fraction very rich in plutonium could be obtained, the lean fraction plutonium content was too high for direct discard. This may still have chemical processing applications. OGMS experiments at low magnetic field strength on incinerator ash did give two fractions but the plutonium content of each fraction was essentially identical. Thus, no chemical processing advantage was identified for magnetic separation of this residue. 6 refs., 1 fig., 9 tabs

  14. Magnetic nano-sorbents for fast separation of radioactive waste

    International Nuclear Information System (INIS)

    In order to find a cost effective and environmentally benign technology to treat the liquid radioactive waste into a safe and stable form for resource recycling or ultimate disposal, this study investigates the separation of radioactive elements from aqueous systems using magnetic nano-sorbents. Our current study focuses on novel magnetic nano-sorbents by attaching DTPA molecules onto the surface of double coated magnetic nanoparticles (dMNPs), and performed preliminary sorption tests using heavy metal ions as surrogates for radionuclides. The results showed that the sorption of cadmium (Cd) and lead (Pb) onto the dMNP-DTPA conjugates was fast, the equilibrium was reached in 30 min. The calculated sorption capacities were 8.06 mg/g for Cd and 12.09 mg/g for Pb. After sorption, the complex of heavy elements captured by nano-sorbents can be easily manipulated and separated from solution in less than 1 min by applying a small external magnetic field. In addition, the sorption results demonstrate that dMNP-DTPA conjugates have a very strong chelating power in highly diluted Cd and Pb solutions (1-10 ?g/L). Therefore, as a simple, fast, and compact process, this separation method has a great potential in the treatment of high level waste with low concentration of transuranic elements compared to tradition nuclear waste treatment. (authors)

  15. Fundamental study on recovery of resources by magnetic separation using superconducting bulk magnet

    International Nuclear Information System (INIS)

    The process of polishing glass substrate is necessary for production of the liquid crystal, thus the substance which mainly consists of CeO2 (ceria) is used as a polishing agent. In this study, we aim to separate impurities selectively from waste slurry and recover ceria particles in order to reuse as a polishing agent. Waste fluid contains impurities such as ferrous particles originating from aggregating agent. We focused on the difference in magnetic property of each particle, and applied the high gradient magnetic separation with superconducting magnet which can separate not only ferromagnetic particle but also paramagnetic particle with relatively high magnetization. We controlled pH based on surface potential of ceria and ferrous particles in order to avoid the aggregation of the waste fluid. As the result of optimization of the conditions such as the geometry of filters, fluid flow rate and pH by calculation and experiment, the sufficient separation efficiency was obtained.

  16. The rate of separation of magnetic lines of force in a random magnetic field.

    Science.gov (United States)

    Jokipii, J. R.

    1973-01-01

    The mixing of magnetic lines of force, as represented by their rate of separation, as a function of distance along the magnetic field, is considered with emphasis on neighboring lines of force. This effect is particularly important in understanding the transport of charged particles perpendicular to the average magnetic field. The calculation is carried out in the approximation that the separation changes by an amount small compared with the correlation scale normal to the field, in a distance along the field of a few correlation scales. It is found that the rate of separation is very sensitive to the precise form of the power spectrum. Application to the interplanetary and interstellar magnetic fields is discussed, and it is shown that in some cases field lines, much closer together than the correlation scale, separate at a rate which is effectively as rapid as if they were many correlation lengths apart.

  17. Magnetically modified biological materials as perspective adsorbents for large-scale magnetic separation processes.

    Czech Academy of Sciences Publication Activity Database

    Mosiniewicz-Szablewska, E.; Šafa?íková, Miroslava; Šafa?ík, Ivo

    New York : Nova Science Publishers, 2010 - (Valencia, R.), s. 301-318 ISBN 978-1-60876-074-9. - (Horizons in World Physics . 266) R&D Projects: GA MPO 2A-1TP1/094; GA MŠk OC09052 Institutional research plan: CEZ:AV0Z60870520 Keywords : magnetic ally modified biological material * magnetic separation * biologically active compounds Subject RIV: CB - Analytical Chemistry, Separation

  18. Application of magnetic separation to steelmaking slags for reclamation.

    Science.gov (United States)

    Alanyali, H; Cöl, M; Yilmaz, M; Karagöz, S

    2006-01-01

    Integrated iron and steel plants generate large amounts of metallurgical slag, which usually contains some quantity of metals or mixtures of oxides that could be treated to be recycled in various applications. The conventional method for disposal of slags is dumping. However, it is possible to process the slags to be used in the production of metallic iron, or as an additive in cement making. In this study, a basic oxygen furnace (BOF) steelwork slag obtained from the Kardemir integrated iron and steel works, Karabuk, Turkey is used. A drum magnetic separator system with pre-engineered crucial processing parameters of drum revolution speed, drum radius, drum flesh thickness, and magnitude of the magnetic field applied is utilized, as these parameters have a competing influence on the results. Subsequently, the effects of slag grain size and the drum-blade gap are investigated in the separation efficiency of magnetic grains. It is found that collection of magnetic grains is improved by decreasing the grain size of slags and moreover, the collection of magnetic grains fraction is increased with an increase in the gap between the blades and drum. PMID:16545952

  19. Characterization of steel grit recovered from ornamental rocks waste by magnetic separation

    International Nuclear Information System (INIS)

    The aim of this work is characterization of steel grit recovered from ornamental rock waste by magnetic separation. The magnetic separation was realized in three steps: first, using a high intensity wet magnetic separator, which used only the remaining magnetic field of equipment. In the second step, the magnetic material obtained in the first phase was subjected to a new manual magnetic separation using rare earth magnets. In a third step, magnetic material obtained with rare earth magnets was subjected to manual magnetic separation using ferrite magnets. After the magnetic separation, the material was sent to characterization which was obtained by chemical analysis, scanning electron microscopy, X-ray diffraction and size analysis. The size analysis showed that the concentrate range from 0,5 to 563,67 ?m with 4 wt.% over 100 ?m and content metallic iron of 93 wt%. (author)

  20. Magnetic reconnection in 3D magnetosphere models: magnetic separators and open flux production

    Science.gov (United States)

    Glocer, A.; Dorelli, J.; Toth, G.; Komar, C. M.; Cassak, P.

    2014-12-01

    There are multiple competing definitions of magnetic reconnection in 3D (e.g., Hesse and Schindler [1988], Lau and Finn [1990], and Boozer [2002]). In this work we focus on separator reconnection. A magnetic separator can be understood as the 3D analogue of a 2D x line with a guide field, and is defined by the line corresponding to the intersection of the separatrix surfaces associated with the magnetic nulls. A separator in the magnetosphere represents the intersection of four distinct magnetic topologies: solar wind, closed, open connected to the northern hemisphere, and open connected to the southern hemisphere. The integral of the parallel electric field along the separator defines the rate of open flux production, and is one measure of the reconnection rate. We present three methods for locating magnetic separators and apply them to 3D resistive MHD simulations of the Earth's magnetosphere using the BATS-R-US code. The techniques for finding separators and determining the reconnection rate are insensitive to IMF clock angle and can in principle be applied to any magnetospheric model. The present work examines cases of high and low resistivity, for two clock angles. We also examine the separator during Flux Transfer Events (FTEs) and Kelvin-Helmholtz instability.

  1. Dynamics of magnetic particles in cylindrical Halbach array: implications for magnetic cell separation and drug targeting.

    Science.gov (United States)

    Babinec, Peter; Krafcík, Andrej; Babincová, Melánia; Rosenecker, Joseph

    2010-08-01

    Magnetic nanoparticles for therapy and diagnosis are at the leading edge of the rapidly developing field of bionanotechnology. In this study, we have theoretically studied motion of magnetic nano- as well as micro-particles in the field of cylindrical Halbach array of permanent magnets. Magnetic flux density was modeled as magnetostatic problem by finite element method and particle motion was described using system of ordinary differential equations--Newton law. Computations were done for nanoparticles Nanomag-D with radius 65 nm, which are often used in magnetic drug targeting, as well as microparticles DynaBeads-M280 with radius 1.4 microm, which can be used for magnetic separation. Analyzing snapshots of trajectories of hundred magnetite particles of each size in the water as well as in the air, we have found that optimally designed magnetic circuits of permanent magnets in quadrupolar Halbach array have substantially shorter capture time than simple blocks of permanent magnets commonly used in experiments, therefore, such a Halbach array may be useful as a potential source of magnetic field for magnetic separation and targeting of magnetic nanoparticles as well as microparticles for delivery of drugs, genes, and cells in various biomedical applications. PMID:20517710

  2. Design of Power Magnetic Chute Separator and Minimization of its External Magnetic Field.

    Czech Academy of Sciences Publication Activity Database

    Karban, P.; Ulrych, B.; Doležel, Ivo

    St. Petersburg : St. Petersburg Polytechnical University, 2005, s. 1-4. ISBN 5-93208-034-0. [International Conference on 2005 IEEE St. Petersburg PowerTech [0046062]. St. Petersburg (RU), 27.06.2005-30.06.2005] Institutional research plan: CEZ:AV0Z20570509 Keywords : magnetic separator * magnetic field * numerical analysis Subject RIV: JA - Electronics ; Optoelectronics, Electrical Engineering

  3. 3D magnetic measurements of the combined function magnets in separator COMBAS

    International Nuclear Information System (INIS)

    The high-resolving wide aperture separator COMBAS has been designed and commissioned at the FLNR, JINR. Three-component magnetic measurements of all the magnets were performed. The measured data allow reconstruction of the 3D-distributions of the fields in all the magnets. 3D-maps are needed for particle trajectory simulations throughout the entire separator. The magnetic fields of analysing magnets, M1, M2, M7, and M8, contain quadrupole components of alternating sign that provide necessary beam focusing. All the magnets M1-M8, contain sextupole and octupole field components, which minimizes the second and third order aberrations. All this allowed one to increase their apertures, to form effectively a beam of the required sizes and to decrease the channel length

  4. Magnetic Separation for Nuclear Material Detection and Surveillance

    International Nuclear Information System (INIS)

    A high performance superconducting magnet is being developed for particle retrieval from field collected samples. Results show that maximum separation effectiveness is obtained when the matrix fiber diameter approaches the diameter of the particles to be captured. Experimentally, the authors obtained a single particle capture limit with 0.8microm PuO2 particles with dodecane as a carrier fluid. The development of new matrix materials is being pursued through the controlled corrosion of stainless steel wool, or the deposition of nickel dendrites on the existing stainless steel matrix material. They have also derived a model from a continuity equation that uses empirically determined capture cross section values. This enables the prediction of high gradient magnetic separator performance for a variety of materials and applications. The model can be used to optimize the capture cross section and thus increase the capture efficiency

  5. Highly Sensitive and Rapid Detection of Pseudomonas aeruginosa Based on Magnetic Enrichment and Magnetic Separation

    OpenAIRE

    Yongjun Tang, Jun Zou

    2013-01-01

    A method for highly sensitive and rapid detection of Pseudomonas aeruginosa, based on magnetic enrichment and magnetic separation, is described in this paper. The magnetic nanoparticles (MNPs) were applied to adsorb genome DNA after the sample was lysed. The DNA binding MNPs were directly subjected to polymerase chain reaction (PCR) to amplify gyrB specific sequence of Pseudomonas aeruginosa. The biotin labeled PCR products were detected by chemiluminescence when they were successively incuba...

  6. Capture of metallic copper by high gradient magnetic separation system.

    Science.gov (United States)

    Wu, Wan-I; Wu, Chung-Hsin; Hong, P K Andy; Lin, Cheng-Fang

    2011-10-01

    Valence copper was recovered from wastewater by chemical reduction and use of a high gradient magnetic separation (HGMS) system. Ammonia (NH3) and sodium dithionate (Na2S2O4) at a molar ratio of [Cu]:[NH3]:[Na2S2O4] = 1:4:3 at pH = 9.5 were used first to chemically reduce copper ion to metallic copper; the resultant metal solids were captured in an upflowing reactor space equipped with a permalloy matrix net under a high gradient magnetic field. The captured solids were predominantly 6-20 microm in diameter, with Cu2O and CuO present among the solids. Four treatment configurations with and without the use of magnetic field and metal alloy as the matrix net were tested and their effects evaluated: (1) no magnetic field or matrix, (2) no magnetic field but with matrix, (3) with magnetic field but no matrix, (4) with both magnetic field and matrix. At flow rates of 40, 60, 80 and 100 cm3/min, capture efficiencies for metallic copper in the absence of magnetic field were 87%, 86%, 63%, and 39%, respectively, and in the presence of magnetic field were 99%, 98%, 95%, and 93%, respectively. The HGMS was critical for a high capture efficiency, whereas a matrix net only marginally enhanced it. Additional tests with a larger reactor confirmed similarly high efficiencies of > 85%. The use of an alloy matrix appeared to be important when high flow rates are most likely to be employed in practical applications. PMID:22329132

  7. Radiolysis and hydrolysis of magnetically assisted chemical separation particles

    International Nuclear Information System (INIS)

    The magnetically assisted chemical separation (MACS) process is designed to separate transuranic (TRU) elements out of high-level waste (HLW) or TRU waste. Magnetic microparticles (1--25 ?m) were coated with octyl (phenyl)N,N-diisobutylcarbamoylmethylphosphine oxide (CMPO) dissolved in tributyl phosphate (TBP) and tested for removing TRU elements from acidic nitrate solutions. The particles were contacted with nitric acid solutions and Hanford plutonium finishing plant (PFP) simulant, irradiated with a high intensity 60Co ?-ray source, and evaluated for effectiveness in removing TRU elements from 2m HNO3 solutions. The resistance of the coatings and magnetic cores to radiolytic damage and hydrolytic degradation was investigated by irradiating samples of particles suspended in a variety of solutions with doses of up to 5 Mrad. Transmission electron microscopy (TEM), magnetic susceptibility measurements, and physical observations of the particles and suspension solutions were used to assess physical changes to the particles. Processes that affect the surface of the particles dramatically alter the binding sites for TRU in solution. Hydrolysis played a larger role than radiolysis in the degradation of the extraction capacity of the particles

  8. Radiation Resistant Magnets for the RIA Fragment Separator

    CERN Document Server

    Zeller, Al; Gupta, Ramesh C; Ronningen, Reginald; Sherrill, Bradley

    2005-01-01

    The high radiation fields around the production target and the beam dump in the fragment separator at the Rare Isotope Accelerator requires that radiation resistant magnets be used. Because large apertures and high gradients are required for the quadrupoles and similar demanding requirements for the dipole and sextupoles, resistive coils are difficult to justify. The radiation heating of any materials at liquid helium temperatures also requires that superconducting versions of the magnets have low cold-masses. The final optical design has taken the practical magnets limits into account and sizes and fields adjusted to what is believed to be achievable with technology that is possible with sufficient R&D. Designs with higher obtainable current densities and having good radiation tolerances that use superconducting coils are presented, as well as the radiation transport calculations that drive the material parameters.

  9. The suspended magnetic separator with large blocks from NdFeB magnets and its long term technological tests.

    Czech Academy of Sciences Publication Activity Database

    Žežulka, Václav; Straka, Pavel

    2011-01-01

    Ro?. 8, ?. 1 (2011), s. 89-97. ISSN 1214-9705 Institutional research plan: CEZ:AV0Z30460519 Keywords : magnetic separation * magnetic separators * magnetic circuits Subject RIV: BM - Solid Matter Physics ; Magnetism Impact factor: 0.530, year: 2011 http://www.irsm.cas.cz/abstracts/AGG/01_11/8_Zezulka.pdf

  10. Characterization of a Prototype Compact High Gradient Magnetic Separator Device for Blood Detoxification.

    Czech Academy of Sciences Publication Activity Database

    Chen, H.; Kaminski, M. D.; Stepp, Patricia Caviness; Holtzman, S.; Rosengart, A. J.

    2009-01-01

    Ro?. 44, ?. 9 (2009), s. 1954-1969. ISSN 0149-6395 Institutional research plan: CEZ:AV0Z40550506 Keywords : magnetic separation * magnetic separator * detoxification * nanotechnology Subject RIV: CE - Biochemistry Impact factor: 1.028, year: 2009

  11. Magnetic design considerations for devices and particles used for biological high-gradient magnetic separation (HGMS) systems

    International Nuclear Information System (INIS)

    An overview of the magnetic systems used in biological high-gradient magnetic separation (HGMS) is presented. The magnetic design parameters of a range of separation devices are discussed. Such designs have distinct magnetic field characteristics and are usually tailored to meet the needs of particular protocols. The various types of magnets and particles are also discussed, with a comparison of materials available and their magnetic properties

  12. New Applications of Magnetic Separation Using Superconducting Magnets and Colloid Chemical Processes

    Science.gov (United States)

    Takeda, S.; Yu, S.-J.; Nakahira, A.; Izumi, Y.; Nishijima, S.; Watanabe, T.

    2005-07-01

    High gradient magnetic separation (HGMS) can be a promising new environmental purification technique as it produces no contaminants, such as flocculants, and could possibly treat large amounts of waste water within a short time frame. A colloid chemical process for magnetic seeding can allow us to rapidly recover a large quantity of adsorbate and to strongly magnetize individual particles in order to improve the recovery efficiency of magnetic separation. In this paper, we will report on the fundamental study of the magnetic seeding process and purification processes using HGMS, and also on studies of applications of the water treatment system for actual factories. Emphasized is a report on a system constructed for water treatment from a paper-manufacturing factory.

  13. Possibilities of power coal desulphurization from upper nitra basin by means of magnetic separation

    OpenAIRE

    Lovás Michal; Jakabský ?tefan; Hredzák Slavomír

    1997-01-01

    The paper deals with the application of magnetic separation in coal desulphurization. Specimens of power coal from Upper Nitra basin were subjected to breaking, grinding and wet high gradient magnetic separation under magnetic field induction of 1,7 T. Sulphidic sulphur contents and recoveries into separation products have been observed.

  14. Possibilities of power coal desulphurization from upper nitra basin by means of magnetic separation

    Directory of Open Access Journals (Sweden)

    Lovás Michal

    1997-09-01

    Full Text Available The paper deals with the application of magnetic separation in coal desulphurization. Specimens of power coal from Upper Nitra basin were subjected to breaking, grinding and wet high gradient magnetic separation under magnetic field induction of 1,7 T. Sulphidic sulphur contents and recoveries into separation products have been observed.

  15. Magnetically separable titania-coated nickel ferrite photocatalyst

    International Nuclear Information System (INIS)

    A magnetically separable photocatalyst was prepared by a continuous multi-step spray pyrolysis process. In the first step, nickel ferrite core particles were prepared by an ultrasonic spray pyrolysis. In the second step, tetraethyl orthosilicate (TEOS) and titanium isopropoxide (TTIP) were sequentially injected and coated on the surface of the core particles. The sequentially coated layers were decomposed to form silica and titania layers in a final furnace reactor. The titania-silica layered particles displayed higher photoactivity than particles coated only with titania and titania-silica mixture-coated particles. The photoactivity of the titania-silica layered particles remained unchanged after magnetic separation and washing. This confirms that the adhesion between the core particles and the coated layer is strong enough to withstand vigorous mixing. It also implies that the formation of free particles of silica or titania is negligible in the second reactor. The strong adhesion between the coated layer and the nickel ferrite core is attributed to the features of the multi-step process, wherein the core particles are exposed to high temperate in the second reactor for only a few seconds and transformation of the core particles into non-magnetic particles is prohibited

  16. Separation of actinides by high-gradient magnetic filtration

    International Nuclear Information System (INIS)

    High-gradient magnetic filtration has been identified as a candidate solid/liquid separation technique for removing actinide particulate from waste streams. Although HGMS is not intended to reduce the activity in the waste stream to below 100 nCi/g, it does offer two significant advantages: (a) selective removal of TRU solids for subsequent secondary processing and (b) reduced operating complications during solvent extraction due to solids accumulation in the interfacial region. Removal of > 95 wt% of the plutonium and americium solids is expected regardless of the solids present and their properties. Verification tests will be performed to validate this assumption

  17. Apparatus for magnetic separation of paramagnetic and diamagnetic material

    Science.gov (United States)

    Doctor, Richard D. (Glen Ellyn, IL)

    1988-01-01

    The present invention relates to methods and apparatus for segregating paramagnetic from diamagnetic particles in particulate material and, in particular, to the open gradient magnetic separation of ash producing components and pyritic sulfur from coal. The apparatus includes a vertical cylinder and a rotatable vertical screw positioned within the cylinder, the screw having a helical blade angled downwardly and outwardly from the axis. Rotation of the vertical screw causes denser particles, which in the case of coal include pyritic sulfur and ash, which are paramagnetic, to migrate to the outside of the screw, and less dense particles, such as the low sulfur organic portion of the coal, which are diamagnetic, to migrate towards the center of the screw. A vibration mechanism attached to the screw causes the screw to vibrate during rotation, agitating and thereby accommodating further segregation of the particles. An open gradient magnetic field is applied circumferentially along the entire length of the screw by a superconducting quadropole magnet. The open gradient magnetic field further segregates the paramagnetic particles from the diamagnetic particles. The paramagnetic particles may then be directed from the cylinder into a first storage bin, and the diamagnetic particles, which are suitable for relatively clean combustion, may be directed into a second storage bin.

  18. Plasma separation process: Magnet move to Oak Ridge National Laboratory

    International Nuclear Information System (INIS)

    This is the final report on the series of operations which culminated with the delivery of the Plasma Separation Process prototype magnet system (PMS) to Building K1432 at Oak Ridge National Laboratory (ORNL). This procedure included real time monitoring of the cold mass support strut strain gauges and an in-cab rider to monitor the instrumentation and direct the driver. The primary technical consideration for these precautions was the possibility of low frequency resonant vibration of the cold mass when excited by symmetrical rough road conditions at specific speeds causing excess stress levels in the support struts and consequent strut failure. A secondary consideration was the possibility of high acceleration loads due to sudden stops, severe road conditions, of impacts. The procedure for moving and transportation to ORNL included requirements for real time continuous monitoring of the eight strut stain gauges and three external accelerometers. Because the strain gauges had not been used since the original magnet cooldown, it was planned to verify their integrity during magnet warmup. The measurements made from the strut strain gauges resulted in stress values that were physically impossible. It was concluded that further evaluation was necessary to verify the usefulness of these gauges and whether they might be faulty. This was accomplished during the removal of the magnet from the building. 6 figs., 1 tab

  19. An open gradient magnetic separator assembled using NdFeB magnets for a use of fine particles remover

    International Nuclear Information System (INIS)

    A drum type magnetic separator was designed and optimized by computer simulation. The separator consisted of rotating outer shell of drum, magnetic flux generator drum which was assembled with numbers of disk type magnet holders, and drum axis around which the magnet holders were fixed. NdFeB magnet blocks were inserted into the disks, and the disks were assembled layer by layer along the drum axis. Magnetic circuits of the separator were simulated on the basis of highest magnetic strength, least cost, and high yield of separation by using a vector field S/W employing the opera-2D program. The separator proved a separation yield of 95% in removing fine iron-base particles, and installed at hot rolling mill of Pohang iron and steel co. in Korea. (orig.)

  20. Thorium-uranium processing with gravity, magnetic and electrical separation in zarigan ore deposit

    International Nuclear Information System (INIS)

    Because of low grade of thorium and uranium in the Zarigan mineral deposit, the pre-concentration operation prior to leaching is necessary. From X-ray diffraction analysis results, it was clear that this ore has large amount of other minerals such as Feldespat, Quartz, Hematite, Titanomagnetite, and rare earths. In this paper the thorium enhancement grade in Zarigan deposit by using gravity, magnetic and electrical separations methods is reported. The output of a Jaw crusher was ground to 85 micron by using ball mill. Then about 95% of SiO2 was separated by using shaking table separation. The heavy concentrate of shaking table was processed by a high intensity magnetic separator and then the magnetic concentrate separated by a low intensity magnetic separator. Finally, the non magnetic concentrate of low magnetic separator was processed with the electrical separation. The grades of thorium and uranium in the non magnetic concentrate of low magnetic separator were increased to 4000 and 5000 ppm, respectively where only 15% of the initial feed (ore) was transferred to this concentrate. Therefore, this resulted in a decrease of acid consumption in the leaching processes and the efficiency enhancement of the process. The pre-treatment circuit of this ore was designed as Jaw crusher/ball mill/shaking table/high-magnetic separator/low-magnetic separator/electrical separator, respectively.

  1. Magnetic microgels, a promising candidate for enhanced magnetic adsorbent particles in bioseparation: synthesis, physicochemical characterization, and separation performance.

    Science.gov (United States)

    Turcu, Rodica; Socoliuc, Vlad; Craciunescu, Izabell; Petran, Anca; Paulus, Anja; Franzreb, Matthias; Vasile, Eugeniu; Vekas, Ladislau

    2015-02-01

    For specific applications in the field of high gradient magnetic separation of biomaterials, magnetic nanoparticle clusters of controlled size and high magnetic moment in an external magnetic field are of particular interest. We report the synthesis and characterization of magnetic microgels designed for magnetic separation purposes, as well as the separation efficiency of the obtained microgel particles. High magnetization magnetic microgels with superparamagnetic behaviour were obtained in a two-step synthesis procedure by a miniemulsion technique using highly stable ferrofluid on a volatile nonpolar carrier. Spherical clusters of closely packed hydrophobic oleic acid-coated magnetite nanoparticles were coated with cross linked polymer shells of polyacrylic acid, poly-N-isopropylacrylamide, and poly-3-acrylamidopropyl trimethylammonium chloride. The morphology, size distribution, chemical surface composition, and magnetic properties of the magnetic microgels were determined using transmission electron microscopy, X-ray photoelectron spectroscopy, and vibrating sample magnetometry. Magnetically induced phase condensation in aqueous suspensions of magnetic microgels was investigated by optical microscopy and static light scattering. The condensed phase consists of elongated oblong structures oriented in the direction of the external magnetic field and may grow up to several microns in thickness and tens or even hundreds of microns in length. The dependence of phase condensation magnetic supersaturation on the magnetic field intensity was determined. The experiments using high gradient magnetic separation show high values of separation efficiency (99.9-99.97%) for the magnetic microgels. PMID:25519891

  2. Primary beneficiation of tantalite using magnetic separation and acid leaching

    Science.gov (United States)

    Nete, M.; Koko, F.; Theron, T.; Purcell, W.; Nel, J. T.

    2014-12-01

    Primary beneficiation was successfully performed prior to dissolution of manganotantalite (sample A) and ferrotantalite (sample C) samples obtained from two different mines in the Naquissupa area, Mozambique. Magnetic separation removed the majority of iron and titanium, whereas H2SO4 leaching removed a large portion of thorium and uranium in these samples. Analytical results indicated that 64.14wt% and 72.04wt% of the total Fe and Ti, respectively, and ˜2wt% each of Nb2O5 and Ta2O5 were removed from sample C (ferrotantalite) using the magnetic separation method, whereas only 9.64wt% and 8.66wt% of total Fe2O3 and TiO2, respectively, and ˜2wt% each of Nb2O5 and Ta2O5 were removed from sample A (manganotantalite). A temperature of 50°C and a leaching time of 3 h in the presence of concentrated H2SO4 were observed to be the most appropriate leaching conditions for removal of radioactive elements from the tantalite ores. The results obtained for sample A under these conditions indicated that 64.14wt% U3O8 and 60.77wt% ThO2 were leached into the acidic solution, along with 4.45wt% and 0.99wt% of Nb2O5 and Ta2O5, respectively.

  3. On-chip Magnetic Separation and Cell Encapsulation in Droplets

    Science.gov (United States)

    Chen, A.; Byvank, T.; Bharde, A.; Miller, B. L.; Chalmers, J. J.; Sooryakumar, R.; Chang, W.-J.; Bashir, R.

    2012-02-01

    The demand for high-throughput single cell assays is gaining importance because of the heterogeneity of many cell suspensions, even after significant initial sorting. These suspensions may display cell-to-cell variability at the gene expression level that could impact single cell functional genomics, cancer, stem-cell research and drug screening. The on-chip monitoring of individual cells in an isolated environment could prevent cross-contamination, provide high recovery yield and ability to study biological traits at a single cell level These advantages of on-chip biological experiments contrast to conventional methods, which require bulk samples that provide only averaged information on cell metabolism. We report on a device that integrates microfluidic technology with a magnetic tweezers array to combine the functionality of separation and encapsulation of objects such as immunomagnetically labeled cells or magnetic beads into pico-liter droplets on the same chip. The ability to control the separation throughput that is independent of the hydrodynamic droplet generation rate allows the encapsulation efficiency to be optimized. The device can potentially be integrated with on-chip labeling and/or bio-detection to become a powerful single-cell analysis device.

  4. Monte Carlo study of phase separation in magnetic insulators

    CERN Document Server

    Murawski, Szymon; Paw?owski, Grzegorz; Robaszkiewicz, Stanis?aw

    2015-01-01

    In this work we focus on the study of phase separation in the zero-bandwidth extended Hubbard with nearest-neighbors intersite Ising-like magnetic interactions $J$ and on-site Coulomb interactions $U$. The system has been analyzed by means of Monte Carlo simulations (in the grand canonical ensemble) on two dimensional square lattice (with $N=L\\times L =400$ sites) and the results for $U/(4J)=2$ as a function of chemical potential and electron concentration have been obtained. Depending on the values of interaction parameters the system exhibits homogeneous (anti-)ferromagnetic (AF) or non-ordered (NO) phase as well as phase separation PS:AF/NO state. Transitions between homogeneous phases (i.e. AF-NO transitions) can be of first or second order and the tricritical point is also present on the phase diagrams. The electron compressibility $K$ is an indicator of the phase separation and that quantity is of particular interest of this paper.

  5. Correlations, spin-charge separation, and magnetic anisotropy

    Science.gov (United States)

    Skomski, Ralph; Manchanda, Priyanka

    2015-03-01

    Much of the physics of condensed matter reflects electron-electron correlations. On an independent-electron level, correlations are described by a single Slater determinant with broken spin symmetry. This approach includes Hund's rule correlations as well the LSDA and LSDA+U approximations to density-functional theory (DFT). However, from Kondo and heavy-fermion systems it is known that the independent-electron approach fails to describe spin-charge separation in strongly correlated systems, necessitating the use of two or more Slater determinants. Using first-principle and model calculations, we show that spin-charge separation strongly affects the leading rare-earth anisotropy contribution in top-end permanent magnet materials such as Nd2Fe14B and SmCo5. Explicit correlation results are obtained for two limiting cases. First, we derive the density functional for tripositive rare-earth ions in a Bethe-type crystal field. The potential looks very different from the LSDA(+U) potentials, including gradient corrections. Second, we use a simple model to show that Kondo-type spin-charge separation yield a rare-earth anisotropy contribution absent in the independent-electron approach. This research is supported by DOE (DE-FG02-04ER46152).

  6. Study on magnetic separation for decontamination of cesium contaminated soil by using superconducting magnet

    Science.gov (United States)

    Igarashi, Susumu; Nomura, Naoki; Mishima, Fumihito; Akiyama, Yoko

    2014-09-01

    The accident of Fukushima Daiichi nuclear power plant caused the diffusion of radioactive cesium over the wide area. We examined the possibility of applying magnetic separation method using the superconducting magnet, which can process a large amount of the soil in high speed, to the soil decontamination and volume reduction of the radioactive cesium contaminated soil. Clay minerals are classified as 2:1 and 1:1 types by the difference of their layer structures, and these types of minerals are respectively paramagnetic and diamagnetic including some exception. It is known that most of the radioactive cesium is strongly adsorbed on the clay, especially on 2:1 type clay minerals. It is expected that the method which can separate only 2:1 type clay minerals selectively from the mixture clay minerals can enormously contribute to the volume reduction of the contaminated soil. In this study, the components in the clay before and after separation were evaluated to estimate the magnetic separation efficiency by using X-ray diffraction. From the results, the decontamination efficiency and the volume reduction ratio were estimated in order to examine the appropriate separation conditions for the practical decontamination of the soil.

  7. Application of high gradient magnetic separation principles to magnetic drug targeting

    International Nuclear Information System (INIS)

    A hypothetical magnetic drug targeting system, utilizing high gradient magnetic separation (HGMS) principles, was studied theoretically using FEMLAB simulations. This new approach uses a ferromagnetic wire placed at a bifurcation point inside a blood vessel and an externally applied magnetic field, to magnetically guide magnetic drug carrier particles (MDCP) through the circulatory system and then to magnetically retain them at a target site. Wire collection (CE) and diversion (DE) efficiencies were defined and used to evaluate the system performance. CE and DE both increase as the strength of the applied magnetic field (0.3-2.0 T), the amount of ferromagnetic material (iron) in the MDCP (20-100%) and the size of the MDCP (1-10 ?m radius) increase, and as the average inlet velocity (0.1-0.8 m s-1), the size of the wire (50-250 ?m radius) and the ratio (4-10) of the parent vessel radius (0.25-1.25 mm radius) to wire radius decrease. The effect of the applied magnetic field direction (0 deg. and 90 deg. ) on CE and DE was minimal. Under these plausible conditions, CEs as high as 70% were obtained, with DEs reaching only 30%; however, when the MDCPs were allowed to agglomerate (4-10 ?m radius), CEs and DEs of 100% were indeed achieved. These results reveal that this new magnetic drug targeting approach for magnetically collecting MDCPs at a target site, even in arteries with very high velocities, is feasible and very promising; this new approach for magnetiromising; this new approach for magnetically guiding MDCPs through the circulatory system is also feasible but more limited. Overall, this study shows that magnetic drug targeting, based on HGMS principles, has considerable promise as an effective drug targeting tool with many potential applications

  8. Tracing magnetic separators and their dependence on IMF clock angle in global magnetospheric simulations

    CERN Document Server

    Komar, C M; Dorelli, J C; Glocer, A; Kuznetsova, M M

    2013-01-01

    A new, efficient, and highly accurate method for tracing magnetic separators in global magnetospheric simulations with arbitrary clock angle is presented. The technique is to begin at a magnetic null and iteratively march along the separator by finding where four magnetic topologies meet on a spherical surface. The technique is verified using exact solutions for separators resulting from an analytic magnetic field model that superposes dipolar and uniform magnetic fields. Global resistive magnetohydrodynamic simulations are performed using the three-dimensional BATS-R-US code with a uniform resistivity, in eight distinct simulations with interplanetary magnetic field (IMF) clock angles ranging from 0 (parallel) to 180 degrees (anti-parallel). Magnetic nulls and separators are found in the simulations, and it is shown that separators traced here are accurate for any clock angle, unlike the last closed field line on the Sun-Earth line that fails for southward IMF. Trends in magnetic null locations and the struc...

  9. Magnetic separation - Advanced nanotechnology for future nuclear fuel recycle

    International Nuclear Information System (INIS)

    The unique properties of magnetic nanoparticles (MNPs), such as their extremely small size and high surface area to volume ratio, provide better kinetics for the adsorption of metal ions from aqueous solutions. In this work, we demonstrated the separation of minor actinides using complex conjugates of MNPs with diethylenetriamine-pentaacetic acid (DTPA) chelator. The sorption results show the strong affinity of DTPA towards Am (III) and Pu (IV) by extracting 97% and 80% of actinides, respectively. It is shown that the extraction process is highly dependent on the pH of the solution. If these long-term heat generating actinides can be efficiently removed from the used fuel raffinates, the volume of material that can be placed in a given amount of repository space can be significantly increased. (authors)

  10. Demonstration of magnetically activated and guided isotope separation

    Science.gov (United States)

    Mazur, Thomas R.; Klappauf, Bruce; Raizen, Mark G.

    2014-08-01

    Enriched isotopes are widely used in medicine, basic science and energy production, and the need will only grow in the future. The main method for enriching stable isotopes today, the calutron, dates back over eighty years and has an uncertain future, creating an urgent need, especially in nuclear medicine. We report here the experimental realization of a general and efficient method for isotope separation that presents a viable alternative to the calutron. Combining optical pumping and a unique magnet geometry, we observe substantial depletion of Li-6 throughput in a lithium atomic beam produced by an evaporation source over a range of flux. These results demonstrate the viability of our method to yield large degrees of enrichment in a manner that is amenable to industrial scale-up and the production of commercially relevant quantities.

  11. IMPROVEMENT OF IMMUNOMAGNETIC SEPARATION FOR ESCHERICHIA COLI O157:H7 DETECTION BY THE PICKPEN MAGNETIC PARTICLE SEPARATION DEVICE

    Science.gov (United States)

    Conventional immunomagnetic separation (IMS) procedures, which use an external magnetic source to capture magnetic particles against the side of a test tube, are labor intensive and can have poor sensitivity for the target organism due to high background microflora that is not effectively washed awa...

  12. Trapped field enhancement of five-aligned superconducting bulk magnetized by pulse field for magnetic separation

    International Nuclear Information System (INIS)

    Five-aligned superconducting bulk magnet system has been improved and the trapped field characteristics have been investigated by the pulse field magnetization (PFM). The trapped field BT(z = 0 mm) is enhanced to 2.7 T at the bulk surface because of the lowering temperature Ts and the enhancement of the applied field Bex, compared with those for the proto-type system [Physica C 445-448 (2006) 399]. The operating fields, BT(2 mm) at the vacuum sheath surface and BT(9 mm) at the surface of the rotating membrane in water-treatment system, are also enhanced because of some structural improvement, and the multi-bulk magnet system available for the magnetic separation is realized

  13. Titania deposited on soft magnetic activated carbon as a magnetically separable photocatalyst with enhanced activity

    Science.gov (United States)

    Wang, Shaohua; Zhou, Shaoqi

    2010-08-01

    Magnetically separable composite photocatalysts, TiO 2 deposited on soft magnetic ferrite activated carbon (TFAC), were prepared by sol-gel and dip-coating technique. The prepared composites were characterized by X-ray diffraction (XRD), field emission scanning electron microscopy (FESEM), Fourier transform infrared spectra (FTIR), optical absorption spectroscopy, vibrating sample magnetometer (VSM) and nitrogen adsorption. These photocatalysts exhibited enhanced photocatalytic activity compared to Degussa P25 for the degradation of methyl orange (MO) in aqueous solution. The kinetics of MO degradation was well fitted to the Langmuir-Hinshelwood model. The samples showed good magnetic response and could be completely recovered by an external magnet. Furthermore, the photocatalysts could maintain high photocatalytic activity after five cycles, and the degradation rate of MO was still close to 90%.

  14. Magnetic separation studies on ferruginous chromite fine to enhance Cr:Fe ratio

    Science.gov (United States)

    Tripathy, Sunil Kumar; Banerjee, P. K.; Suresh, Nikkam

    2015-03-01

    The Cr:Fe ratio (chromium-to-iron mass ratio) of chromite affects the production of chrome-based ferroalloys. Although the literature contains numerous reports related to the magnetic separation of different minerals, limited work concerning the application of magnetic separation to fine chromite from the Sukinda region of India to enhance its Cr:Fe ratio has been reported. In the present investigation, magnetic separation and mineralogical characterization studies of chromite fines were conducted to enhance the Cr:Fe ratio. Characterization studies included particle size and chemical analyses, X-ray diffraction analysis, automated mineral analysis, sink-and-float studies, and magnetic susceptibility measurements, whereas magnetic separation was investigated using a rare earth drum magnetic separator, a rare earth roll magnetic separator, an induced roll magnetic separator, and a wet high-intensity magnetic separator. The fine chromite was observed to be upgraded to a Cr:Fe ratio of 2.2 with a yield of 55.7% through the use of an induced roll magnetic separator and a feed material with a Cr:Fe ratio of 1.6.

  15. Magnetic separation technique for groundwater by five HTS melt-processed bulk magnets arranged in a line

    International Nuclear Information System (INIS)

    A magnetic separation was practically conducted by 10-pole HTS bulk magnets. The HTS bulk magnets were activated to 2.5 T by feeding pulsed fields of 6 T. The separation ratio of actual groundwater exceeded 70% at less than 4.8 l/min. The flocks without magnetite powder were obviously attracted to the magnetic poles. A magnetic separation study for groundwater purification has been practically conducted by using the multi-pole magnet system. The magnetic pole was composed of 10 open magnetic spaces by arranging five HTS melt-processed bulk magnets in a line in a vacuum sheath. The individual bulk magnets were activated by feeding intense pulsed magnetic fields up to 6 T. The magnetic field distribution was estimated with respect to various pole arrangements. The actual groundwater samples of Sanjo City were processed so as to form large precipitates by adding the coagulant and pH controlling. The maximum separation ratio of the iron-bearing precipitates has exceeded over 70% when slurry water was exposed to 10 magnetic poles of up to 2.5 T at a flowing rate of less than 4.8 l/min. An obvious attraction of flocks to the magnetic poles was observed even when the water contains no magnetite powder at the flow rate of 1.01 l/min. This implies the validity of the multi-pole magnet system with respect to the actual application to water purification.

  16. Magnetic separation technique for groundwater by five HTS melt-processed bulk magnets arranged in a line

    Energy Technology Data Exchange (ETDEWEB)

    Oka, T., E-mail: okat@eng.niigata-u.ac.jp [Niigata University, 8050 Ikarashi-Nino-Cho, Nishi-ku, Niigata 950-2181 (Japan); Seki, H.; Kimura, T.; Mimura, D.; Fukui, S.; Ogawa, J.; Sato, T.; Ooizumi, M. [Niigata University, 8050 Ikarashi-Nino-Cho, Nishi-ku, Niigata 950-2181 (Japan); Fujishiro, H. [Iwate University, 4-3-5 Ueda, Morioka 020-8551 (Japan); Hayashi, H. [Kyushu Electric Co., 2-1-47 Shiobaru, Minami-ku, Fukuoka 815-8520 (Japan); Yokoyama, K. [Ashikaga Institute of Technology, 268-1 Ohmae-cho, Ashikaga, Tochigi 326-8558 (Japan); Stiehler, C. [IFW Dresden, Helmholzstr., 20-01069 Dresden (Germany)

    2011-11-15

    A magnetic separation was practically conducted by 10-pole HTS bulk magnets. The HTS bulk magnets were activated to 2.5 T by feeding pulsed fields of 6 T. The separation ratio of actual groundwater exceeded 70% at less than 4.8 l/min. The flocks without magnetite powder were obviously attracted to the magnetic poles. A magnetic separation study for groundwater purification has been practically conducted by using the multi-pole magnet system. The magnetic pole was composed of 10 open magnetic spaces by arranging five HTS melt-processed bulk magnets in a line in a vacuum sheath. The individual bulk magnets were activated by feeding intense pulsed magnetic fields up to 6 T. The magnetic field distribution was estimated with respect to various pole arrangements. The actual groundwater samples of Sanjo City were processed so as to form large precipitates by adding the coagulant and pH controlling. The maximum separation ratio of the iron-bearing precipitates has exceeded over 70% when slurry water was exposed to 10 magnetic poles of up to 2.5 T at a flowing rate of less than 4.8 l/min. An obvious attraction of flocks to the magnetic poles was observed even when the water contains no magnetite powder at the flow rate of 1.01 l/min. This implies the validity of the multi-pole magnet system with respect to the actual application to water purification.

  17. Development of superconducting high gradient magnetic separation system for highly viscous fluid for practical use

    Science.gov (United States)

    Hayashi, S.; Mishima, F.; Akiyama, Y.; Nishijima, S.

    2011-11-01

    In the industrial plants processing highly viscous fluid such as foods or industrial products, it is necessary to remove the metallic wear debris originating from pipe in manufacturing line which triggers quality loss. In this study, we developed a high gradient magnetic separation (HGMS) system which consists of superconducting magnet to remove the metallic wear debris. The magnetic separation experiment and the particle trajectory simulation were conducted with polyvinyl alcohol (PVA) as a model material (viscosity coefficient was 10 Pa s, which is 10,000 times higher than that in water). In order to develop a magnetic separation system for practical use, the particle trajectory simulation by using solenoidal superconducting magnet was conducted, and the possibility of the magnetic separation for removing ferromagnetic stainless steel (SUS) particles in highly viscous fluid of 10 Pa s was indicated. Based on the results, the number of filters to obtain required separation efficiency was examined to design the practical separation system.

  18. Mercury removal from solution by superconducting magnetic separation with nanostructured magnetic adsorbents

    International Nuclear Information System (INIS)

    Recently, mercury Hg concentration in human blood increases due to expanding the global mercury contamination. Excess mercury bioaccumulation poses a significant health risk. In order to decrease mercury concentration in the environment and human blood, we have developed two different kinds of nanostructured magnetic adsorbents for mercury to apply them to superconducting magnetic separation instead of conventional filtration. One is magnetic beads (MBs) which have nanosize magnetite particles in the core and a lot of SH radicals on the surface to adsorb Hg ions effectively. MBs were developed mainly to remove mercury from human blood. The maximum amount of the adsorption for MBs is 6.3 mg/g in the solution in less than a minute. Dithiothreitol can easily remove mercury adsorbed to MBs, hence MBs can be reusable. The other is nanostructured magnetic activated carbon (MAC) which is activated carbon with mesopores and nanosize magnetite. The maximum amount of the adsorption for MAC is 38.3 mg/g in the solution. By heat-treatment mercury can be easily removed from MAC. We have studied superconducting magnetic separation using each adsorbent for mercury removal from solution.

  19. A study on a magnetic separation of radioactive corrosion products from NPP using permanent magnets

    International Nuclear Information System (INIS)

    It is important to emphasize that the current trend to longer fuel cycles (18-24 months) has complicated the dilemma of finding optimum chemical condition for the primary coolant because of some problems such as increase of radioactive corrosion products, possibility of axial offset anomaly and so on. Radioactive corrosion products which are generated by the neutron activation of general corrosion products at a nuclear power plant are the major source of occupational radiation exposure. Generally, radioactive corrosion products exit in soluble and insoluble forms, and are removed by ion exchangers and purification filters. Most of the insoluble radioactive corrosion products have the characteristic of showing strong ferrimagnetism. Along with the new development and production of permanent magnets (rare earth magnets) which generate much stronger magnetic fields than conventional permanent magnets, a new type of magnetic filter is suggested that can efficiently separate corrosion products using rotation of permanent magnets. This new magnetic filter reveals good performance results in filtering magnetite, cobalt ferrite and nickel ferrite from aqueous coolant simulation

  20. Large Scale Magnetic Separation of Solanum tuberosum Tuber Lectin from Potato Starch Waste Water

    Science.gov (United States)

    Safarik, Ivo; Horska, Katerina; Martinez, Lluis M.; Safarikova, Mirka

    2010-12-01

    A simple procedure for large scale isolation of Solanum tuberosum tuber lectin from potato starch industry waste water has been developed. The procedure employed magnetic chitosan microparticles as an affinity adsorbent. Magnetic separation was performed in a flow-through magnetic separation system. The adsorbed lectin was eluted with glycine/HCl buffer, pH 2.2. The specific activity of separated lectin increased approximately 27 times during the isolation process.

  1. SUPERCONDUCTING OPEN-GRADIENT MAGNETIC SEPARATION FOR THE PRETREATMENT OF RADIOACTIVE OR MIXED WASTE VITRIFICATION FEEDS

    Science.gov (United States)

    Scientists need to gain a better understanding of the magnetic separation processes that can be used to separate deleterious constituents (crystalline, amorphous, and colloidal) in vitrification feed streams for borosilicate glass production without adding chemicals or generating...

  2. Collection of Ni-bearing material from electroless plating waste by magnetic separation with HTS bulk magnet

    International Nuclear Information System (INIS)

    Highlights: ? The magnetic separation for Ni compounds was conducted by HTS bulk magnet. ? The coarse Ni-sulfate crystals were formed from the Ni-phosphite precipitates. ? Ni-sulfate crystals was separated from the mixture of Ni-sulfate and Ni-phosphite compounds. -- Abstract: The magnetic separation experiment to collect the Ni compounds from the waste liquid of electroless plating processes was conducted in the open-gradient magnetic separation process with the high temperature superconducting bulk magnet system. The magnetic pole containing Gd-based bulk superconductors was activated to 3.45 T at 35 K in the static magnetic field of 5 T with use of a superconducting solenoid magnet. The coarse Ni-sulfate crystals were formed by adding the concentrated sulfuric acid to the Ni-phosphite precipitates which yielded from the plating waste liquid by controlling the temperature and the pH value. The open-gradient magnetic separation technique was employed to separate the Ni-sulfate crystals from the mixture of the Ni-sulfate and Ni-phosphite compounds by the difference between their magnetic properties. And we succeeded in collecting Ni-sulfate crystals preferentially to the Ni-phosphite by attracting them to the magnetic pole soon after the Ni-sulfate crystals began to grow

  3. Collection of Ni-bearing material from electroless plating waste by magnetic separation with HTS bulk magnet

    Energy Technology Data Exchange (ETDEWEB)

    Oka, T., E-mail: okat@eng.niigata-u.ac.jp [Niigata University, 8050 Ikarashi-Ninocho, Nishi-ku, Niigata 950-2181 (Japan); Fukazawa, H.; Fukui, S.; Ogawa, J.; Sato, T.; Ooizumi, M. [Niigata University, 8050 Ikarashi-Ninocho, Nishi-ku, Niigata 950-2181 (Japan); Tsujimura, M. [Aichi Giken Co., 50-1 Takeshita, Hitotugi-cho, Kariya, Aichi 448-0003 (Japan); Yokoyama, K. [Ashikaga Institute of Technology, 268-1 Ohmae-cho, Ashikaga, Tochigi 326-8558 (Japan)

    2014-01-15

    Highlights: ? The magnetic separation for Ni compounds was conducted by HTS bulk magnet. ? The coarse Ni-sulfate crystals were formed from the Ni-phosphite precipitates. ? Ni-sulfate crystals was separated from the mixture of Ni-sulfate and Ni-phosphite compounds. -- Abstract: The magnetic separation experiment to collect the Ni compounds from the waste liquid of electroless plating processes was conducted in the open-gradient magnetic separation process with the high temperature superconducting bulk magnet system. The magnetic pole containing Gd-based bulk superconductors was activated to 3.45 T at 35 K in the static magnetic field of 5 T with use of a superconducting solenoid magnet. The coarse Ni-sulfate crystals were formed by adding the concentrated sulfuric acid to the Ni-phosphite precipitates which yielded from the plating waste liquid by controlling the temperature and the pH value. The open-gradient magnetic separation technique was employed to separate the Ni-sulfate crystals from the mixture of the Ni-sulfate and Ni-phosphite compounds by the difference between their magnetic properties. And we succeeded in collecting Ni-sulfate crystals preferentially to the Ni-phosphite by attracting them to the magnetic pole soon after the Ni-sulfate crystals began to grow.

  4. Lab on a chip for continuous-flow magnetic cell separation.

    Science.gov (United States)

    Hejazian, Majid; Li, Weihua; Nguyen, Nam-Trung

    2015-02-21

    Separation of cells is a key application area of lab-on-a-chip (LOC) devices. Among the various methods, magnetic separation of cells utilizing microfluidic devices offers the merits of biocompatibility, efficiency, and simplicity. This review discusses the fundamental physics involved in using magnetic force to separate particles, and identifies the optimisation parameters and corresponding methods for increasing the magnetic force. The paper then elaborates the design considerations of LOC devices for continuous-flow magnetic cell separation. Examples from the recently published literature illustrate these state-of-the-art techniques. PMID:25537573

  5. Continuous sheath-free magnetic separation of particles in a U-shaped microchannel

    OpenAIRE

    Liang, Litao; Xuan, Xiangchun

    2012-01-01

    Particle separation is important to many chemical and biomedical applications. Magnetic field-induced particle separation is simple, cheap, and free of fluid heating issues that accompany electric, acoustic, and optical methods. We develop herein a novel microfluidic approach to continuous sheath-free magnetic separation of particles. This approach exploits the negative or positive magnetophoretic deflection to focus and separate particles in the two branches of a U-shaped microchannel, respe...

  6. A time-dependent model for magnetic reconnection in the presence of a separator

    OpenAIRE

    Wilmot-Smith, A. L.; Hornig, G.

    2011-01-01

    We present a model for separator reconnection due to an isolated reconnection process. Separator reconnection is a process which occurs in the neighbourhood of a distinguished field line (the separator) connecting two null points of a magnetic field. It is, for example, important for the dynamics of magnetic flux at the dayside magnetopause and in the solar corona. We find that, above a certain threshold, such a reconnection process generates new separators which leads to a ...

  7. SUPERCONDUCTING MAGNET FOR 60 TONNE/HOUR MINERAL SEPARATOR WITH CLOSED CYCLE 4 KELVIN REFRIGERATION

    OpenAIRE

    Good, J.; White, K

    1984-01-01

    Cryogenic Consultants Limited has constructed a superconducting magnet system for magnetic separation, with a three metre long dipole magnet cooled by a closed-cycle refrigerator. This paper considers the design and construction of the magnet system in relation to a theoretical expression for processing capacity.

  8. Magnetic separation of particles and cells in ferrofluid flow through a straight microchannel using two offset magnets

    International Nuclear Information System (INIS)

    The separation of particles and cells is critical in many chemical and biological applications. This work presents a simple idea for utilizing a pair of permanent magnets to continuously separate diamagnetic particles and cells in ferrofluid flow through a straight microchannel. The first magnet is placed close to the microchannel for focusing the particle mixture to a single stream without the use of a sheath flow. The second magnet, which is offset from the first magnet and placed farther from the channel, is to displace the aligned particles to dissimilar flow paths for a continuous sorting. This idea is first demonstrated through the separation of 3 ?m- and 10 ?m-diameter polystyrene particles, where the effects of flow speed and magnet distance are both examined. The experimental data are found to fit well with the predictions of an analytical model. Furthermore, a continuous separation of live yeast cells from 10 ?m polystyrene particles is implemented in the same device. - Highlights: • We develop a simple diamagnetic particle and cell separation technique in ferrofluids. • Two offset magnets are used to achieve a sheath-free continuous separation in a straight microchannel. • The technique is demonstrated through the magnetic separation of polystyrene particles and yeast cells. • The effects of ferrofluid speed and magnet-channel distance are examined on particle separation. • The predictions from an analytical model agree with the experimental data quantitatively

  9. Magnetic separation of particles and cells in ferrofluid flow through a straight microchannel using two offset magnets

    Energy Technology Data Exchange (ETDEWEB)

    Zeng, Jian; Deng, Yanxiang [Department of Mechanical Engineering, Clemson University, Clemson, SC 29634-0921 (United States); Vedantam, Pallavi; Tzeng, Tzuen-Rong [Department of Biological Sciences, Clemson University, Clemson, SC 29634-0314 (United States); Xuan, Xiangchun, E-mail: xcxuan@clemson.edu [Department of Mechanical Engineering, Clemson University, Clemson, SC 29634-0921 (United States)

    2013-11-15

    The separation of particles and cells is critical in many chemical and biological applications. This work presents a simple idea for utilizing a pair of permanent magnets to continuously separate diamagnetic particles and cells in ferrofluid flow through a straight microchannel. The first magnet is placed close to the microchannel for focusing the particle mixture to a single stream without the use of a sheath flow. The second magnet, which is offset from the first magnet and placed farther from the channel, is to displace the aligned particles to dissimilar flow paths for a continuous sorting. This idea is first demonstrated through the separation of 3 ?m- and 10 ?m-diameter polystyrene particles, where the effects of flow speed and magnet distance are both examined. The experimental data are found to fit well with the predictions of an analytical model. Furthermore, a continuous separation of live yeast cells from 10 ?m polystyrene particles is implemented in the same device. - Highlights: • We develop a simple diamagnetic particle and cell separation technique in ferrofluids. • Two offset magnets are used to achieve a sheath-free continuous separation in a straight microchannel. • The technique is demonstrated through the magnetic separation of polystyrene particles and yeast cells. • The effects of ferrofluid speed and magnet-channel distance are examined on particle separation. • The predictions from an analytical model agree with the experimental data quantitatively.

  10. Application of high temperature superconductors to high-gradient magnetic separation

    International Nuclear Information System (INIS)

    High Gradient Magnetic Separation (HGMS) is a powerful technique which can be used to separate widely dispersed contaminants from a host material. This technology can separate magnetic solids from other solids, liquids or gases. As the name implies HGMS uses large magnetic field gradients to separate ferromagnetic and paramagnetic particles. HGMS separators usually consist of a high-field solenoid magnet, the bore of which contains a fine-structured, ferromagnetic matrix material. The matrix material locally distorts the magnetic field and creates large field gradients in the vicinity of the matrix elements. These elements then become trapping sites for magnetic particles and are the basis for the magnetic separation. In this paper the authors discuss the design and construction of a prototype HGMS unit using a magnet made with high temperature superconductors (HTS). The prototype consists of an outer vacuum vessel which contains the HTS solenoid magnet. The magnet is surrounded by a thermal radiation shield and multilayer insulation (MLI) blankets. The magnet, thermal shield and current leads all operate in a vacuum and are cooled by a cryocooler. High temperature superconducting current leads are used to reduce the heat leak from the ambient environment to the HTS magnet

  11. Conjugates of Actinide Chelator-Magnetic Nanoparticles for Used Fuel Separation Technology

    Energy Technology Data Exchange (ETDEWEB)

    Qiang, You; Paszczynski, Andrzej; Rao, Linfeng

    2011-10-30

    The actinide separation method using magnetic nanoparticles (MNPs) functionalized with actinide specific chelators utilizes the separation capability of ligand and the ease of magnetic separation. This separation method eliminated the need of large quantity organic solutions used in the liquid-liquid extraction process. The MNPs could also be recycled for repeated separation, thus this separation method greatly reduces the generation of secondary waste compared to traditional liquid extraction technology. The high diffusivity of MNPs and the large surface area also facilitate high efficiency of actinide sorption by the ligands. This method could help in solving the nuclear waste remediation problem.

  12. Theoretical analysis of a new, efficient microfluidic magnetic bead separator based on magnetic structures on multiple length scales

    DEFF Research Database (Denmark)

    Smistrup, Kristian; Bu, Minqiang

    2008-01-01

    We present a theoretical analysis of a new design for microfluidic magnetic bead separation. It combines an external array of mm-sized permanent magnets with magnetization directions alternating between up and down with mu m-sized soft magnetic structures integrated in the bottom of the separation channel. The concept is studied analytically for simple representative geometries and by numerical simulation of an experimentally realistic system geometry. The array of permanent magnets provides long-range magnetic forces that attract the beads to the channel bottom, while the soft magnetic elements provide strong local retaining forces that prevent captured beads from being torn loose by the fluid drag. The addition of the soft magnetic elements increases the maximum retaining force by two orders of magnitude. The design is scalable and provides an efficient and simple solution to the capture of large amounts of magnetic beads on a microsystem platform.

  13. Magnetic separation in microfluidic systems using microfabricated electromagnets - Experiments and simulations

    DEFF Research Database (Denmark)

    Smistrup, Kristian; Hansen, Ole

    2005-01-01

    We present experiments and simulations of magnetic separation of magnetic beads in a microfluidic channel. The separation is obtained by microfabricated electromagnets. The results of our simulations using FEMLAB and Mathematica are compared with experimental results obtained using our own microfabricated systems. (c) 2005 Elsevier B.V. All rights reserved.

  14. Particle Capture Efficiency in a Multi-Wire Model for High Gradient Magnetic Separation

    OpenAIRE

    Eisenträger, Almut; Vella, Dominic; Griffiths, Ian M.

    2014-01-01

    High gradient magnetic separation (HGMS) is an efficient way to remove magnetic and paramagnetic particles, such as heavy metals, from waste water. As the suspension flows through a magnetized filter mesh, high magnetic gradients around the wires attract and capture the particles, removing them from the fluid. We model such a system by considering the motion of a paramagnetic tracer particle through a periodic array of magnetized cylinders. We show that there is a critical M...

  15. A smart fully integrated micromachined separator with soft magnetic micro-pillar arrays for cell isolation

    International Nuclear Information System (INIS)

    A smart fully integrated micromachined separator with soft magnetic micro-pillar arrays has been developed and demonstrated, which can merely employ one independent lab-on-chip to realize cell isolation. The simulation, design, microfabrication and test for the new electromagnetic micro separator were executed. The simulation results of the electromagnetic field in the separator show that special soft magnetic micro-pillar arrays can amplify and redistribute the electromagnetic field generated by the micro-coils. The separator can be equipped with a strong magnetic field to isolate the target cells with a considerably low input current. The micro separator was fabricated by micro-processing technology. An electroplating bath was hired to deposit NiCo/NiFe to fabricate the micro-pillar arrays. An experimental system was set up to verify the function of the micro separator by isolating the lymphocytes, in which the human whole blood mixed with Dynabeads® FlowComp Flexi and monoclonal antibody MHCD2704 was used as the sample. The results show that the electromagnetic micro separator with an extremely low input current can recognize and capture the target lymphocytes with a high efficiency, the separation ratio reaching more than 90% at a lower flow rate. For the electromagnetic micro separator, there is no external magnetizing field required, and there is no extra cooling system because there is less Joule heat generated due to the lower current. The magnetic separator is totally reusable, and it can be used to separate cells or proteins with common antigens

  16. Rapid Multi-Target Immuno-Magnetic Separation through Programmable DNA Linker Displacement

    OpenAIRE

    Probst, Christine E.; Zrazhevskiy, Pavel; Gao, Xiaohu

    2011-01-01

    Immuno-magnetic separation has become an essential tool for high throughout and low cost isolation of biomolecules and cells from heterogeneous samples. However, as magnetic selection is essentially a “black-and-white” assay, its application has been largely restricted to single-target and single-parameter studies. To address this issue, we have developed an immuno-magnetic separation technology that can quickly sort multiple targets at high yield and purity using selectively displaceable...

  17. Development of superconducting high gradient magnetic separation system for highly viscous fluid for practical use

    International Nuclear Information System (INIS)

    The HGMS system to remove the metallic wear debris was developed. The possibility of magnetic separation was indicated by simulation and experiment. The number of filters to obtain required separation rate was examined to design. In the industrial plants processing highly viscous fluid such as foods or industrial products, it is necessary to remove the metallic wear debris originating from pipe in manufacturing line which triggers quality loss. In this study, we developed a high gradient magnetic separation (HGMS) system which consists of superconducting magnet to remove the metallic wear debris. The magnetic separation experiment and the particle trajectory simulation were conducted with polyvinyl alcohol (PVA) as a model material (viscosity coefficient was 10 Pa s, which is 10,000 times higher than that in water). In order to develop a magnetic separation system for practical use, the particle trajectory simulation by using solenoidal superconducting magnet was conducted, and the possibility of the magnetic separation for removing ferromagnetic stainless steel (SUS) particles in highly viscous fluid of 10 Pa s was indicated. Based on the results, the number of filters to obtain required separation efficiency was examined to design the practical separation system.

  18. Coupled particle–fluid transport and magnetic separation in microfluidic systems with passive magnetic functionality

    International Nuclear Information System (INIS)

    A study is presented of coupled particle–fluid transport and field-directed particle capture in microfluidic systems with passive magnetic functionality. These systems consist of a microfluidic flow cell on a substrate that contains embedded magnetic elements. Two systems are considered that utilize soft- and hard-magnetic elements, respectively. In the former, an external field is applied to magnetize the elements, and in the latter, they are permanently magnetized. The field produced by the magnetized elements permeates into the flow cell giving rise to an attractive force on magnetic particles that flow through it. The systems are studied using a novel numerical/closed-form modelling approach that combines numerical transport analysis with closed-form field analysis. Particle–fluid transport is computed using computational fluid dynamics (CFD), while the magnetic force that governs particle capture is obtained in closed form. The CFD analysis takes into account dominant particle forces and two-way momentum transfer between the particles and the fluid. The two-way particle–fluid coupling capability is an important feature of the model that distinguishes it from more commonly used and simplified one-way coupling analysis. The model is used to quantify the impact of two-way particle–fluid coupling on both the capture efficiency and the flow pattern in the systems considered. Many effects such as particle-induced flow-enhanced capture efficiency and flow circulcapture efficiency and flow circulation are studied that cannot be predicted using one-way coupling analysis. In addition, dilute particle dispersions are shown to exhibit significant localized particle–fluid coupling near the capture regions, which contradicts the commonly held view that two-way coupling can be ignored when analysing high-gradient magnetic separation involving such particle systems. Overall, the model demonstrates that two-way coupling needs to be taken into account for rigorous predictions of capture efficiency, especially for applications involving high particle loading and/or low flow rates. It is computationally more efficient and accurate than purely numerical models and should prove useful for the rational design and optimization of novel magnetophoretic microsystems. (paper)

  19. Coupled particle-fluid transport and magnetic separation in microfluidic systems with passive magnetic functionality

    Science.gov (United States)

    Khashan, Saud A.; Furlani, Edward P.

    2013-03-01

    A study is presented of coupled particle-fluid transport and field-directed particle capture in microfluidic systems with passive magnetic functionality. These systems consist of a microfluidic flow cell on a substrate that contains embedded magnetic elements. Two systems are considered that utilize soft- and hard-magnetic elements, respectively. In the former, an external field is applied to magnetize the elements, and in the latter, they are permanently magnetized. The field produced by the magnetized elements permeates into the flow cell giving rise to an attractive force on magnetic particles that flow through it. The systems are studied using a novel numerical/closed-form modelling approach that combines numerical transport analysis with closed-form field analysis. Particle-fluid transport is computed using computational fluid dynamics (CFD), while the magnetic force that governs particle capture is obtained in closed form. The CFD analysis takes into account dominant particle forces and two-way momentum transfer between the particles and the fluid. The two-way particle-fluid coupling capability is an important feature of the model that distinguishes it from more commonly used and simplified one-way coupling analysis. The model is used to quantify the impact of two-way particle-fluid coupling on both the capture efficiency and the flow pattern in the systems considered. Many effects such as particle-induced flow-enhanced capture efficiency and flow circulation are studied that cannot be predicted using one-way coupling analysis. In addition, dilute particle dispersions are shown to exhibit significant localized particle-fluid coupling near the capture regions, which contradicts the commonly held view that two-way coupling can be ignored when analysing high-gradient magnetic separation involving such particle systems. Overall, the model demonstrates that two-way coupling needs to be taken into account for rigorous predictions of capture efficiency, especially for applications involving high particle loading and/or low flow rates. It is computationally more efficient and accurate than purely numerical models and should prove useful for the rational design and optimization of novel magnetophoretic microsystems.

  20. Open gradient magnetic separation utilizing NbTi, Nb3Sn and Bi-2223 materials

    International Nuclear Information System (INIS)

    Superconducting magnets enable the magnetic separation of particles with small magnetic susceptibility. In this paper, we compare superconducting separator magnets made of Nb3Sn, NbTi and Bi-2223 materials. The separator system is used to determine the optimal conditions for separation of various slurries. The magnet should provide a high and nearly constant magnetic force density. These requirements are met with racetrack coils. Geometries consisting of one or two racetracks have been examined. In order to keep the material costs at a reasonable level, the volume of the magnet has been minimized taking into account the constraints set by the force and current densities. Sequential quadratic programming (SQP) was used in the optimization procedure. The force density has been calculated using an analytical two-dimensional model. The critical current density of the coil was obtained by solving the magnetic flux density from a three-dimensional model using the finite element method. We have compared magnetic force densities and wire lengths in magnets made of different materials. For magnets made of low-temperature superconductors, the optimized geometry consisted of two coils. For magnets made of high-temperature superconductors, the minimum volume was achieved by using only one coil. (author)

  1. HIGH-GRADIENT MAGNETIC SEPARATION FOR REMOVAL OF SULFUR FROM COAL

    Science.gov (United States)

    The report gives results of a thorough physical, chemical, and magnetic characterization of a Pennsylvania coal from the Upper Freeport seam. The powdered coal was then subjected to high-gradient magnetic separations, as a function of magnetic field and fluid velocity, in both a ...

  2. Purification of condenser water in thermal power station by superconducting magnetic separation

    International Nuclear Information System (INIS)

    Magnetic separation using cryo-cooled Nb-Ti superconducting magnet was applied for the purification of condenser water. Iron oxides in condenser water were effectively removed by superconducting magnetic separation. The effect of magnetic field strength and filter size was determined. Thermal power station is made up of a steam turbine and a steam condenser which need a lot of water. The water of steam condenser should be replaced, since scales consisting of iron oxide mainly are accumulated on the surface of condenser pipes as it goes. Superconducting high gradient magnetic separation (HGMS) system has merits to remove paramagnetic substance like iron oxides because it can generate higher magnetic field strength than electromagnet or permanent magnet. In this paper, cryo-cooled Nb-Ti superconducting magnet that can generate up to 6 T was used for HGMS systems. Magnetic filters were designed by the analysis of magnetic field distribution at superconducting magnets. The result of X-ray analysis showed contaminants were mostly ?-Fe2O3 (hematite) and ?-Fe2O3 (maghemite). The higher magnetic field was applied up to 6 T, the more iron oxides were removed. As the wire diameter of magnetic filter decreased, the turbidity removal of the sample was enhanced.

  3. Magnetite/CdTe magnetic-fluorescent composite nanosystem for magnetic separation and bio-imaging

    International Nuclear Information System (INIS)

    A new synthesis protocol is described to obtain a CdTe decorated magnetite bifunctional nanosystem via dodecylamine (DDA) as cross linker. High resolution transmission electron microscopy (HRTEM), energy-dispersive x-ray spectroscopy (EDAX), vibrating sample magnetometry (VSM), Fourier transform infrared spectroscopy (FTIR), diffuse reflectance spectroscopy (DRS) and fluorescence microscopy are used to characterize the constitution, size, composition and physical properties of these superparamagnetic-fluorescent nanoparticles. These CdTe decorated magnetite nanoparticles were then functionalized with anti-epidermal growth factor receptor (EGFR) antibody to specifically target cells expressing this receptor. The EGFR is a transmembrane glycoprotein and is expressed on tumor cells from different tissue origins including human leukemic cell line Molt-4 cells. The magnetite-CdTe composite nanosystem is shown to perform excellently for specific selection, magnetic separation and fluorescent detection of EGFR positive Molt-4 cells from a mixed population. Flow cytometry and confocal laser scanning microscopy results show that this composite nanosystem has great potential in antibody functionalized magnetic separation and imaging of cells using cell surface receptor antibody.

  4. Collection of Ni-bearing material from electroless plating waste by magnetic separation with HTS bulk magnet

    Science.gov (United States)

    Oka, T.; Fukazawa, H.; Fukui, S.; Ogawa, J.; Sato, T.; Ooizumi, M.; Tsujimura, M.; Yokoyama, K.

    2014-01-01

    The magnetic separation experiment to collect the Ni compounds from the waste liquid of electroless plating processes was conducted in the open-gradient magnetic separation process with the high temperature superconducting bulk magnet system. The magnetic pole containing Gd-based bulk superconductors was activated to 3.45 T at 35 K in the static magnetic field of 5 T with use of a superconducting solenoid magnet. The coarse Ni-sulfate crystals were formed by adding the concentrated sulfuric acid to the Ni-phosphite precipitates which yielded from the plating waste liquid by controlling the temperature and the pH value. The open-gradient magnetic separation technique was employed to separate the Ni-sulfate crystals from the mixture of the Ni-sulfate and Ni-phosphite compounds by the difference between their magnetic properties. And we succeeded in collecting Ni-sulfate crystals preferentially to the Ni-phosphite by attracting them to the magnetic pole soon after the Ni-sulfate crystals began to grow.

  5. Proposal for implanting a magnetic stable isotope separator

    International Nuclear Information System (INIS)

    The implantation of an electromagnetic isotope separator able to separate elements of mass from 20 to 250 a.m.u., with an enrichment factor from 10 to 200 times the initial concentration, depending on the elements, is proposed. The most suitable separator type for Brazilian CNEN, considering building installations and minimum conditions for the equipment facilities, the retinue chronogram, the infrastructure, and the personnel training for operation is defined. (M.C.K.)

  6. Ferritin conjugates as specific magnetic labels. Implications for cell separation.

    OpenAIRE

    Odette, L. L.; Mccloskey, M. A.; Young, S. H.

    1984-01-01

    Concanavalin A coupled to the naturally occurring iron storage protein ferritin is used to label rat erythrocytes and increase the cells' magnetic susceptibility. Labeled cells are introduced into a chamber containing spherical iron particles and the chamber is placed in a uniform 5.2 kG (gauss) magnetic field. The trajectory of cells in the inhomogeneous magnetic field around the iron particles and the polar distributions of cells bound to the iron particles compare well with the theoretical...

  7. Chiral magnetic microspheres purified by centrifugal field flow fractionation and microspheres magnetic chiral chromatography for benzoin racemate separation

    OpenAIRE

    Tian, Ailin; Qi, Jing; Liu, Yating; Wang, Fengkang; Ito, Yoichiro; Wei, Yun

    2013-01-01

    Separation of enantiomers still remains a challenge due to their identical physical and chemical properties in a chiral environment, and the research on specific chiral selector along with separation techniques continues to be conducted to resolve individual enantiomers. In our laboratory the promising magnetic chiral microspheres Fe3O4@SiO2@cellulose-2, 3-bis (3, 5-dimethylphenylcarbamate) have been developed to facilitate the resolution using both its magnetic property and chiral recognitio...

  8. On-chip magnetic separation of superparamagnetic beads for integrated molecular analysis

    OpenAIRE

    Florescu, Octavian; Wang, Kevan; Au, Patrick; Tang, Jimmy; Harris, Eva; Beatty, P. Robert; Boser, Bernhard E.

    2010-01-01

    We have demonstrated a postprocessed complementary metal oxide semiconductor (CMOS) integrated circuit (IC) capable of on-chip magnetic separation, i.e., removing via magnetic forces the nonspecifically bound magnetic beads from the detection area on the surface of the chip. Initially, 4.5 ?m wide superparamagnetic beads sedimenting out of solution due to gravity were attracted to the detection area by a magnetic concentration force generated by flowing current through a conductor embedded i...

  9. Magnetic properties and loss separation in iron-silicone-MnZn ferrite soft magnetic composites

    Science.gov (United States)

    Wu, Shen; Sun, Aizhi; Xu, Wenhuan; Zou, Chao; Yang, Jun; Dong, Juan

    2013-12-01

    This paper investigates the magnetic and structural properties of iron-based soft magnetic composites coated with silicone-MnZn ferrite hybrid. The organic silicone resin was added to improve the flexibility of the insulated iron powder and causes better adhesion between particles to increase the mechanical properties. Scanning electron microscopy and distribution maps show that the iron particle surface is covered with a thin layer of silicone-MnZn ferrite. Silicone-MnZn ferrite coated samples have higher permeability when compared with the non-magnetic silicone resin coated compacts. The real part of permeability increases by 34.18% when compared with the silicone resin coated samples at 20 kHz. In this work, a formula for calculating the total loss component by loss separation method is presented and finally the different parts of total losses are calculated. The results show that the eddy current loss coefficient is close to each other for the silicone-MnZn ferrite, silicone resin and MnZn ferrite coated samples (0.0078loss coefficient is lower for the silicone-MnZn ferrite coated sample (k2 =1.4058) in comparison with other samples.

  10. Magnetic properties and loss separation in iron-silicone-MnZn ferrite soft magnetic composites

    International Nuclear Information System (INIS)

    This paper investigates the magnetic and structural properties of iron-based soft magnetic composites coated with silicone-MnZn ferrite hybrid. The organic silicone resin was added to improve the flexibility of the insulated iron powder and causes better adhesion between particles to increase the mechanical properties. Scanning electron microscopy and distribution maps show that the iron particle surface is covered with a thin layer of silicone-MnZn ferrite. Silicone-MnZn ferrite coated samples have higher permeability when compared with the non-magnetic silicone resin coated compacts. The real part of permeability increases by 34.18% when compared with the silicone resin coated samples at 20 kHz. In this work, a formula for calculating the total loss component by loss separation method is presented and finally the different parts of total losses are calculated. The results show that the eddy current loss coefficient is close to each other for the silicone-MnZn ferrite, silicone resin and MnZn ferrite coated samples (0.007832 =1.4058) in comparison with other samples

  11. Highly Sensitive and Rapid Detection of Pseudomonas aeruginosa Based on Magnetic Enrichment and Magnetic Separation

    Directory of Open Access Journals (Sweden)

    Yongjun Tang, Jun Zou, Chao Ma, Zeeshan Ali, Zhiyang Li, Xiaolong Li, Ninging Ma, Xianbo Mou, Yan Deng, Liming Zhang, Kai Li, Guangming Lu, Haowen Yang, Nongyue He

    2013-01-01

    Full Text Available A method for highly sensitive and rapid detection of Pseudomonas aeruginosa, based on magnetic enrichment and magnetic separation, is described in this paper. The magnetic nanoparticles (MNPs were applied to adsorb genome DNA after the sample was lysed. The DNA binding MNPs were directly subjected to polymerase chain reaction (PCR to amplify gyrB specific sequence of Pseudomonas aeruginosa. The biotin labeled PCR products were detected by chemiluminescence when they were successively incubated with the probes-modified MNPs and alkaline phosphatase (ALP labeled streptavidin (SA. Agarose gel electrophoresis analyses approved the method of in situ PCR to be highly reliable. The factors which could affect the chemiluminiscence were studied in detail. The results showed that the MNPs of 400 nm in diameter are beneficial to the detection. The sequence length and the binding site of the probe with a target sequence have obvious effects on the detection. The optimal concentration of the probes, hybridization temperature and hybridization time were 10 ?M, 60 ºC and 60 mins, respectively. The method of in situ PCR based on MNPs can greatly improve the utilization rate of the DNA template ultimately enhancing the detection sensitivity. Experiment results proved that the primer and probe had high specificity, and Pseudomonas aeruginosa was successfully detected with detection limits as low as 10 cfu/mL by this method, while the detection of a single Pseudomonas aeruginosa can also be achieved.

  12. Highly sensitive and rapid detection of Pseudomonas aeruginosa based on magnetic enrichment and magnetic separation.

    Science.gov (United States)

    Tang, Yongjun; Zou, Jun; Ma, Chao; Ali, Zeeshan; Li, Zhiyang; Li, Xiaolong; Ma, Ninging; Mou, Xianbo; Deng, Yan; Zhang, Liming; Li, Kai; Lu, Guangming; Yang, Haowen; He, Nongyue

    2013-01-01

    A method for highly sensitive and rapid detection of Pseudomonas aeruginosa, based on magnetic enrichment and magnetic separation, is described in this paper. The magnetic nanoparticles (MNPs) were applied to adsorb genome DNA after the sample was lysed. The DNA binding MNPs were directly subjected to polymerase chain reaction (PCR) to amplify gyrB specific sequence of Pseudomonas aeruginosa. The biotin labeled PCR products were detected by chemiluminescence when they were successively incubated with the probes-modified MNPs and alkaline phosphatase (ALP) labeled streptavidin (SA). Agarose gel electrophoresis analyses approved the method of in situ PCR to be highly reliable. The factors which could affect the chemiluminiscence were studied in detail. The results showed that the MNPs of 400 nm in diameter are beneficial to the detection. The sequence length and the binding site of the probe with a target sequence have obvious effects on the detection. The optimal concentration of the probes, hybridization temperature and hybridization time were 10 ?M, 60 ºC and 60 mins, respectively. The method of in situ PCR based on MNPs can greatly improve the utilization rate of the DNA template ultimately enhancing the detection sensitivity. Experiment results proved that the primer and probe had high specificity, and Pseudomonas aeruginosa was successfully detected with detection limits as low as 10 cfu/mL by this method, while the detection of a single Pseudomonas aeruginosa can also be achieved. PMID:23424183

  13. Micelles, magnets and molecular mechanisms. Application to cage effects and isotope separation

    International Nuclear Information System (INIS)

    This report reviews the general problem of cage reactions of radical pairs and diradicals. Based on Wigner's spin conservation rule and the expectation that only singlet radical pairs can undergo cage reactions, a natural consequence is the expectation that it should be possible to observe magnetic effects on the reactions of radical pairs. It is shown that two types of magnetic effects should be possible: (1) Effects due to the application of the magnetic field of a laboratory magnet during a reaction; (2) Effects due to the interactions of nuclear magnetic moments and electron magnetic moments. The experimental consequences of these magnetic effects are separation of isotopes based on differing nuclear magnetic moments and variation of the extent of cage reaction by variation of an applied field or by variation of nuclear magnetic moments. Striking experimental examples of these magnetic effects are provided by the photolysis of ketones in micellar solution and by the thermolysis of endoperoxides. (author)

  14. Preliminary 3-D analysis of a high gradient magnetic separator for biomedical applications

    International Nuclear Information System (INIS)

    A prototype portable high-gradient magnetic separator is being developed for in vivo magnetic separation from human blood flow. In this separator design, an array of biocompatible capillary tubing and magnetizable wires is immersed in an external magnetic field, which is generated by two parallel permanent magnets. The wires are magnetized and the high magnetic field gradient from the magnetized wires helps to collect blood-borne magnetic nanospheres. In this study, a 3-D mathematical model was created and the effect of tubing-wire configurations on the capture efficiency (CE) of the system was analyzed using COMSOL Multiphysics 3.3. The results show that an optimal design was a configuration characterized by bi-directionally alternating wires and tubes as an optimal design. In vitro experiments verified the theoretical predictions for the CE. The CE of the optimal design was more than 20% higher than that of the other design at 20 cm/s. The results further optimized a prototype portable magnetic separator suitable for rapid sequestration of magnetic nanospheres from the human blood stream while accommodating necessary clinical boundary conditions

  15. Separation and Focusing of Magnetic Beads for Agglutination Tests

    OpenAIRE

    Afshar Ghasemlouy, Rana

    2011-01-01

    Functional magnetic micro- and nanoparticles are used in bioanalytical applications as solid carriers for capture, transport and detection of biomolecules or magnetically labeled cells. Colloidal suspensions of such particles provide a large specific surface for chemical binding and therefore allow highly efficient interactions with target molecules in a sample solution. Controlled actuation and manipulation of these mobile substrates in the microflui...

  16. Phase separation in La-Ca manganites: Magnetic field effects

    Science.gov (United States)

    Tovar, M.; Causa, M. T.; Ramos, C. A.; Laura-Ccahuana, D.

    The coexistence of magnetic phases seems to be a characteristic of the La-Ca family of in colossal magnetoresistant manganites. We have analyzed this phenomenon in terms of a free energy, F, where magnetic and electronic contributions of two coexistent phases are included. Three order parameters describe the behavior of the mixed material: the magnetization of each phase and the metallic fraction. Due to the coupling between order parameters there is a range: T**? T? T* where coexistence is possible. Values for the phenomenological parameters are obtained from the experiment. In this paper we analyze the effects of an applied magnetic field on the range of T where the phase coexistence takes place, based on results obtained from dc-magnetization and ESR measurements.

  17. Phase separation in La-Ca manganites: Magnetic field effects

    International Nuclear Information System (INIS)

    The coexistence of magnetic phases seems to be a characteristic of the La-Ca family of in colossal magnetoresistant manganites. We have analyzed this phenomenon in terms of a free energy, F, where magnetic and electronic contributions of two coexistent phases are included. Three order parameters describe the behavior of the mixed material: the magnetization of each phase and the metallic fraction. Due to the coupling between order parameters there is a range: T**?T?T* where coexistence is possible. Values for the phenomenological parameters are obtained from the experiment. In this paper we analyze the effects of an applied magnetic field on the range of T where the phase coexistence takes place, based on results obtained from dc-magnetization and ESR measurements

  18. Fluctuations of the Solitary Bubble at the Separation from the Air Cavity, Compressed by the Magnetic Field in Magnetic Liquid

    OpenAIRE

    Boev, M. L.; Polunin, V. M.; Lobova, O. V.; Shabanova, I. A.; Chervjakov, L. M.; Ryapolov, A. N.

    2013-01-01

    In the article, on the basis of the concept of "display" of geometry of a free surface of the "low-magnetic" environment by the topography of isolines of the module of intensity of a magnetic field, it is studied a form of a free surface of magnetic fluid in a static condition at the initial stage of rapprochement of a ring magnet with a surface of a column of magnetic fluid in a tube and at a stage of pressing of a cavity to a bottom. It is shown that the separation of bubbles from an air ca...

  19. Large Scale Magnetic Separation of Solanum tuberosum Tuber Lectin from Potato Starch Waste Water.

    Czech Academy of Sciences Publication Activity Database

    Šafa?ík, Ivo; Horská, Kate?ina; Martinez, L. M.; Šafa?íková, Miroslava

    Melville : American institute of physics , 2010 - (Häfeli, U.; Schütt, W.; Zborowski, M.), s. 146-151 ISBN 978-0-7354-0866-1. ISSN 0094-243X. - (AIP Conference Proceedings. 1311). [International Conference on the Scientific and Clinical Applications of Magnetic Carriers /8./. Rostock (DE), 25.05.2010-29.05.2010] Institutional research plan: CEZ:AV0Z60870520 Keywords : drug delivery * magnetic microspheres and ferrofluids * magnetic nanospheres * molecular biology * stem cell separation * starch production * potato waste water * magnetic separation * chitosan * lectin * Solanum tuberosum Subject RIV: EH - Ecology, Behaviour

  20. Neutron scattering evidence for magnetic-field-driven abrut magnetic and structural transitions in a phase-separated manganite.

    Czech Academy of Sciences Publication Activity Database

    Yaicle, C.; Martin, C.; Jirák, Zden?k; Fauth, F.; André, G.; Suard, E.; Maignan, A.; Hardy, V.; Retoux, R.; Hervieu, M.

    2003-01-01

    Ro?. 68, ?. 22 (2003), s. 224412-1 - 224412-8. ISSN 0163-1829 Institutional research plan: CEZ:AV0Z1010914 Keywords : phase-separated manganite * magnetic and structural transitions * neutron scattering Subject RIV: BM - Solid Matter Physics ; Magnetism Impact factor: 2.962, year: 2003

  1. Fabrication program of NbTi and Nb3Sn superconducting magnets for mineral separation and high magnetic field generation

    International Nuclear Information System (INIS)

    This paper describes the design of two superconducting magnets for industrial and laboratory use: a 7T NbTi split-pair type magnet, 168 mm of clear bore and 350 KJ of stored energy to be operated in parallel and opposition current modes of ruse as a High Gradient Magnetic Separation (HGMS) system and as a Helical Channel Magnetic Separation (HCMS), respectively; and a 12T mixed type magnet composed of one Nb3Sn inner coil and one NbTi outer coil with 75 mm of clear bore, field homogeneity of 1% in a D.S.V. of 50 mm. This configuration causes the reduction of cost due to the use of graded conductors according to the magnetic field which they are exposed

  2. Closed-loop magnetic separation of nanoparticles on a packed bed of spheres

    Science.gov (United States)

    Magnet, Cécilia; Akouala, Mesferdon; Kuzhir, Pavel; Bossis, Georges; Zubarev, Andrey; Wereley, Norman M.

    2015-05-01

    In this work, we consider magnetic separation of iron oxide nanoparticles when a nanoparticle suspension (diluted ferrofluid) passes through a closed-loop filter composed of a packed bed of micro-beads magnetized by an externally applied magnetic field. We show that the capture of nanoparticles of a size as small as 60 nm is easily achieved at low-to-moderate magnetic fields (16-32 kA/m) thanks to relatively strong magnetic interactions between them. The key parameter governing the capture process is the Mason number—the ratio of hydrodynamic-to-magnetic forces exerted to nanoparticles. The filter efficiency, ?, defined through the ratio of the inlet-to-outlet concentration shows a power-law dependency on Mason number, ??M a-0.83 , in the range of 102nanoparticles, followed by magnetic separation of the nanoparticles.

  3. The use of magnetic isotope effect for the separation of uranium isotopes

    International Nuclear Information System (INIS)

    The influence of the magnetic isotope effect on the reaction of radical pairs containing radical-ion UO22+, is investigated. This can be further used in the new method of uranium isotope separation in chemical reaction

  4. Magnetically separable nanoferrite-anchored glutathione: Aqueous homocoupling of arylboronic acids under microwave irradiation

    Science.gov (United States)

    A highly active, stable and magnetically separable glutathione based organocatalyst provided good to excellent yields to symmetric biaryls in the homocoupling of arylboronic acids under microwave irradiation. Symmetrical biaryl motifs are present in a wide range of natural p...

  5. Magnetic particle separation in viscous flows by BEM

    OpenAIRE

    Hribers?ek, Matjaz?; Ravnik, Jure; Kocutar, Primoz?

    2012-01-01

    A boundary element method based solver for particle motion simulation in dilute suspensions under the influence of hydrodynamic and magnetic forces was applied. The Euler-Lagrangian formulation for simulation of dilute two-phase flow was applied. The algorithm solves the incompressible Navier-Stokes equations written in velocity-vorticity formulation. The non uniform magnetic field was defined analytically for the case of a set of long thin wires. The particle trajectories were computed by ap...

  6. Colossal magnetoresistance and phase separation in magnetic semiconductors

    CERN Document Server

    Nagaev, Eduard L

    2002-01-01

    Colossal magnetoresistance materials, to which manganites and conventional ferromagnetic semiconductors belong, draw great attention because of their intriguing physical properties and the excellent prospects for their practical applications in electronic devices. In addition, magnetic semiconductors are basic materials for high-temperature conductors, and it is impossible to construct a theory of the latter without elucidating properties of the former.This book presents theoretical and experimental results on manganites and conventional magnetic semiconductors, with emphasis on the former. It

  7. Electric Charge Separation in Strong Transient Magnetic Fields

    OpenAIRE

    Asakawa, Masayuki; Majumder, Abhijit; Mu?ller, Berndt

    2010-01-01

    We discuss various mechanisms for the creation of an asymmetric charge fluctuation with respect to the reaction plane among hadrons emitted in relativistic heavy-ion collisions. We show that such mechanisms exist in both, the hadronic gas and the partonic phases of QCD. The mechanisms considered here all require the presence of a strong magnetic field (the ``chiral magnetic effect''), but they do not involve parity or charge-parity violations. We analyze how a transient loca...

  8. Solar flares on November 5, 1980 as a result of magnetic reconnection on the separator

    International Nuclear Information System (INIS)

    On the basis of a simple model of potential magnetic field of the active region AR 2776, it is shown that all the characteristic features observed of the flares on 1980 November 5 can be explained within the framework of a model of a current sheet formed on the separator. The flare filaments and the intersecting X-ray loops are consequences of topological structure of magnetic field near the separator

  9. Application of magnetic separation technology for the processing of a colemanite ore

    Scientific Electronic Library Online (English)

    I., Alp.

    2009-02-01

    Full Text Available Application of magnetic separation was investigated for the enrichment of colemanite ores by removing the magnetic gangue fraction. The detailed XRD analysis of the ore has indicated that the gangue fraction is composed predominantly of the iron-bearing silicates such as smectite and, to a lesser ex [...] tent, illite. Magnetic susceptibility measurements of the colemanite and gangue samples have proved that colemanite is diamagnetic in character whereas gangue fraction is weakly paramagnetic to allow the removal of this fraction by magnetic separation. Magnetic separation of the crushed and sized ore samples (-5 mm +75 ?m) was erformed using a high intensity permanent magnetic separator. Under the test conditions a colemanite concentrate (41.29 wt.% B2O3) was found to be produced from the crushed ore (30.76 wt.% B2O3) at a recovery of 96.76%. These findings suggest that magnetic separation has great potential as an alternative process for the production of a concentrate of commercially sufficient grade.

  10. Separability of center of mass and relative motion of hydrogen in very strong magnetic fields

    International Nuclear Information System (INIS)

    While hydrogen does not strictly separate into center of mass (CMS) and relative motion in a magnetic field, a judicious gauge choice does lead to a simple Hamiltonian whose form in a state of zero translational motion of the center of mass is that of a charged particle in a magnetic field plus a coulomb potential

  11. Method for producing a collector to be used in a magnetic separator - The completed collector

    International Nuclear Information System (INIS)

    This invention concerns a method for coating ferromagnetic bodies with a protective metal withstanding nitric acid, by isostatic compression to form the collectors to be utilized in magnetic separators to isolate magnetic particles from liquids and particularly for the elimination of particles contained in liquids during nuclear fuel reprocessing

  12. Phase separation and enhanced charge-spin coupling near magnetic transitions

    OpenAIRE

    Guinea, F.; Gomez-santos, G.; Arovas, D.

    1999-01-01

    The generic changes of the electronic compressibility in systems which show magnetic instabilities is studied. It is shown that, when going into the ordered phase, the compressibility is reduced by an amount comparable to the its original value, making charge instabilities also possible. We discuss, within this framework, the tendency towards phase separation of the double exchange systems, the pyrochlores, and other magnetic materials.

  13. Separation of magnetic beads in a microfluidic device - Modeling and experimentation

    OpenAIRE

    Tsai, SSH; Wexler, JS; Griffiths, IM; Stone, HA

    2011-01-01

    We describe a microfluidic system that uses a magnetic field to deflect paramagnetic beads in the direction normal to the flow. Through modeling and experimentation, we study this system to separate beads by their magnetic properties and size. We also use a similar system to move the beads from one fluid stream to an adjacent miscible stream. Copyright © 2011 by ASME.

  14. On separation behavior of the devices with rotating plasma in crossed electric and magnetic fields

    International Nuclear Information System (INIS)

    The results of the researches of cylindrical plasma, rotated in the crossed electric and magnetic fields are considered. Calculations and experiments have showed that at certain correlations of the electric and magnetic fields heating and separation of ions of different sorts is possible due to power supply of radial electric-field system.

  15. Particle capture efficiency in a multi-wire model for high gradient magnetic separation

    Science.gov (United States)

    Eisenträger, Almut; Vella, Dominic; Griffiths, Ian M.

    2014-07-01

    High gradient magnetic separation (HGMS) is an efficient way to remove magnetic and paramagnetic particles, such as heavy metals, from waste water. As the suspension flows through a magnetized filter mesh, high magnetic gradients around the wires attract and capture the particles removing them from the fluid. We model such a system by considering the motion of a paramagnetic tracer particle through a periodic array of magnetized cylinders. We show that there is a critical Mason number (ratio of viscous to magnetic forces) below which the particle is captured irrespective of its initial position in the array. Above this threshold, particle capture is only partially successful and depends on the particle's entry position. We determine the relationship between the critical Mason number and the system geometry using numerical and asymptotic calculations. If a capture efficiency below 100% is sufficient, our results demonstrate how operating the HGMS system above the critical Mason number but with multiple separation cycles may increase efficiency.

  16. Magnetically induced two-phase separation in Co-Ge and Co-Si systems

    International Nuclear Information System (INIS)

    Thermodynamic assessments of Co-Ge and Co-Si systems were carried out by the CALPHAD technique. Magnetic and non-magnetic terms were approximated by the Hillert and Jarl description and a sub-regular solution model, respectively. Almost all experimental data were well described by the present set of thermodynamic parameters. The calculated results predict that the magnetically induced two-phase separation occurs in the Co-Ge system

  17. Effect of viscosity and temperature of hexafluoroacetone photolysis solutions on magnetic isotope separation efficiency

    International Nuclear Information System (INIS)

    Dependence of magnetic isotope effect on viscosity and temperature of hexafluoroacetone solutions in perfluorooctane and perfluorinated dibutyl ether is established. It is shown that the obtained dependences of carbon isotope magnetic separation efficiency on temperature and viscosity of solutions have marked maximum for both solvents. Inconsistency of this maximum position for different solvents with respect to a viscosity value is attributed to the dependence of the magnetic isotope effect on hexafluoroacetone photolysis mechanism

  18. Fluctuations of the Solitary Bubble at the Separation from the Air Cavity, Compressed by the Magnetic Field in Magnetic Liquid

    Directory of Open Access Journals (Sweden)

    M.L. Boev

    2013-12-01

    Full Text Available In the article, on the basis of the concept of "display" of geometry of a free surface of the "low-magnetic" environment by the topography of isolines of the module of intensity of a magnetic field, it is studied a form of a free surface of magnetic fluid in a static condition at the initial stage of rapprochement of a ring magnet with a surface of a column of magnetic fluid in a tube and at a stage of pressing of a cavity to a bottom. It is shown that the separation of bubbles from an air cavity occurs in close proximity to the plane of symmetry of a ring magnet on its axis. It is described the method and experimental installation for studying the possibility of electromagnetic indication of sizes of the air bubbles, being in magnetic fluid. It is discussed the results of experimental research on process of a separation of solitary air bubble from a cavity, contained in magnetic fluid and squeezed by ponderomotive forces of a magnetic field which are of interest for creation of essentially new technique of the dosed supply of small amount of gas in the reactor.

  19. Electro-magnetic separation for stable isotopes of Osmium

    International Nuclear Information System (INIS)

    High purity Osmium isotopes (Os-187, Os-192, Os-190 etc.) have great important applications in scientific research, industry and radiotherapy for cancer. The authors have done some experiments on separation and preparation of Osmium isotopes using the existing laboratory- scale EMIS at SINR. Source improvement, change material preparation, mass calibration and so on have been done on the system. Some experimental results are also given

  20. Separation of magnetically isolated TNF receptosomes from mitochondria.

    Science.gov (United States)

    Tchikov, Vladimir; Fritsch, Jürgen; Schütze, Stefan

    2014-01-01

    We previously demonstrated that tumor necrosis factor receptor-1 (TNF-R1) initiates distinct TNF signaling pathways depending on the localization of the receptor. While TNF-R1 at the plasma membrane transmits proinflammatory and antiapoptotic signals, internalized TNF-R1 forms signaling endosomes (TNF receptosomes) that transmit proapoptotic signals. These findings were obtained by a novel technique for the isolation of morphologically intact endocytic vesicles containing magnetically labeled TNF-R1 complexes using a high-gradient, free-flow magnetic chamber. Since intact mitochondria appeared to be a major contaminating organelle in these preparations, we subsequently included a second purification step by iodixanol density centrifugation to obtain a mitochondria-free receptosome preparation. PMID:24377932

  1. Phase separation dynamics in a two-dimensional magnetic mixture

    OpenAIRE

    Lichtner, K.; Archer, A. J.; Klapp, S. H. L.

    2011-01-01

    Based on classical density functional theory (DFT), we investigate the demixing phase transition of a two-dimensional, binary Heisenberg fluid mixture. The particles in the mixture are modeled as Gaussian soft spheres, where one component is characterized by an additional classical spin-spin interaction of Heisenberg type. Within the DFT we treat the particle interactions using a mean-field approximation. For certain magnetic coupling strengths we calculate phase diagrams in...

  2. SASSY, a gas-filled magnetic separator for the study of fusion reaction products

    International Nuclear Information System (INIS)

    A gas-filled on-line recoil separator at the Berkeley SuperHILAC is described. The separator consists of a magnetic dipole and a quadrupole doublet. The system is filled with He at a pressure of about 1 Torr (? 130 Pa). It separates particles according to their average magnetic rigidity. This allows a separation of evaporation residues, scattered target atoms and beam projectiles in a nuclear reaction. The separation time is in the order of 10-6 s; the transmission is about 50% for evaporation residues, less than 10-3 for scattered target-like recoil ions and transfer products, and about 10-15 for full energy beam projectiles. Experimental data over a wide range of reactions are given and it is shown that the average charge of the recoils is determined by the atomic shell structure of the moving ionized atom in the gas. (orig.)

  3. Hour-glass magnetic excitations induced by nanoscopic phase separation in cobalt oxides

    Science.gov (United States)

    Drees, Y.; Li, Z. W.; Ricci, A.; Rotter, M.; Schmidt, W.; Lamago, D.; Sobolev, O.; Rütt, U.; Gutowski, O.; Sprung, M.; Piovano, A.; Castellan, J. P.; Komarek, A. C.

    2014-12-01

    The magnetic excitations in the cuprate superconductors might be essential for an understanding of high-temperature superconductivity. In these cuprate superconductors the magnetic excitation spectrum resembles an hour-glass and certain resonant magnetic excitations within are believed to be connected to the pairing mechanism, which is corroborated by the observation of a universal linear scaling of superconducting gap and magnetic resonance energy. So far, charge stripes are widely believed to be involved in the physics of hour-glass spectra. Here we study an isostructural cobaltate that also exhibits an hour-glass magnetic spectrum. Instead of the expected charge stripe order we observe nano phase separation and unravel a microscopically split origin of hour-glass spectra on the nano scale pointing to a connection between the magnetic resonance peak and the spin gap originating in islands of the antiferromagnetic parent insulator. Our findings open new ways to theories of magnetic excitations and superconductivity in cuprate superconductors.

  4. High gradient magnetic separation versus expanded bed adsorption: a first principle comparison

    DEFF Research Database (Denmark)

    Hubbuch, Jürgen; Matthiesen, D.B.

    2001-01-01

    A robust new adsorptive separation technique specifically designed for direct product capture from crude bioprocess feedstreams is introduced and compared with the current bench mark technique, expanded bed adsorption. The method employs product adsorption onto sub-micron sized non-porous superparamagnetic supports followed by rapid separation of the `loaded' adsorbents from the feedstock using high gradient magnetic separation technology. For the recovery of Savinase(R) from a cell-free Bacillus clausii fermentation liquor using bacitracin-linked adsorbents, the integrated magnetic separation system exhibited substantially enhanced productivity over expanded bed adsorption when operated at processing velocities greater than 48 m h(-1). Use of the bacitracin- linked magnetic supports for a single cycle of batch adsorption and subsequent capture by high gradient magnetic separation at a processing rate of 12 m h(-1) resulted in a 2.2-fold higher productivity relative to expanded bed adsorption, while an increase in adsorbent collection rate to 72 m h(-1) raised the productivity to 10.7 times that of expanded bed adsorption. When the number of batch adsorption cycles was then increased to three, significant drops in both magnetic adsorbent consumption (3.6 fold) and filter volume required (1.3 fold) could be achieved at the expense of a reduction in productivity from 10.7 to 4.4 times that of expanded bed adsorption.

  5. Ferronickel enrichment by fine particle reduction and magnetic separation from nickel laterite ore

    Science.gov (United States)

    Tang, Xiao-hui; Liu, Run-zao; Yao, Li; Ji, Zhi-jun; Zhang, Yan-ting; Li, Shi-qi

    2014-10-01

    Ferronickel enrichment and extraction from nickel laterite ore were studied through reduction and magnetic separation. Reduction experiments were performed using hydrogen and carbon monoxide as reductants at different temperatures (700-1000°C). Magnetic separation of the reduced products was conducted using a SLon-100 cycle pulsating magnetic separator (1.2 T). Composition analysis indicates that the nickel laterite ore contains a total iron content of 22.50wt% and a total nickel content of 1.91wt%. Its mineral composition mainly consists of serpentine, hortonolite, and goethite. During the reduction process, the grade of nickel and iron in the products increases with increasing reduction temperature. Although a higher temperature is more favorable for reduction, the temperature exceeding 1000°C results in sintering of the products, preventing magnetic separation. After magnetic separation, the maximum total nickel and iron concentrations are 5.43wt% and 56.86wt%, and the corresponding recovery rates are 84.38% and 53.76%, respectively.

  6. Magnetically assisted chemical separation (MACS) process: Preparation and optimization of particles for removal of transuranic elements

    International Nuclear Information System (INIS)

    The Magnetically Assisted Chemical Separation (MACS) process combines the selectivity afforded by solvent extractants with magnetic separation by using specially coated magnetic particles to provide a more efficient chemical separation of transuranic (TRU) elements, other radionuclides, and heavy metals from waste streams. Development of the MACS process uses chemical and physical techniques to elucidate the properties of particle coatings and the extent of radiolytic and chemical damage to the particles, and to optimize the stages of loading, extraction, and particle regeneration. This report describes the development of a separation process for TRU elements from various high-level waste streams. Polymer-coated ferromagnetic particles with an adsorbed layer of octyl(phenyl)-N,N-diisobutylcarbamoylmethylphosphine oxide (CMPO) diluted with tributyl phosphate (TBP) were evaluated for use in the separation and recovery of americium and plutonium from nuclear waste solutions. Due to their chemical nature, these extractants selectively complex americium and plutonium contaminants onto the particles, which can then be recovered from the solution by using a magnet. The partition coefficients were larger than those expected based on liquid[liquid extractions, and the extraction proceeded with rapid kinetics. Extractants were stripped from the particles with alcohols and 400-fold volume reductions were achieved. Particles were more sensitive to acid hydrolysis than to radiolysis. Overall, the optimization of a suitable NMCS particle for TRU separation was achieved under simulant conditions, and a MACS unit is currently being designed for an in-lab demonstration

  7. Magnetically assisted chemical separation (MACS) process: Preparation and optimization of particles for removal of transuranic elements

    Energy Technology Data Exchange (ETDEWEB)

    Nunez, L.; Kaminski, M.; Bradley, C.; Buchholz, B.A.; Aase, S.B.; Tuazon, H.E.; Vandegrift, G.F. [Argonne National Lab., IL (United States); Landsberger, S. [Univ. of Illinois, Urbana, IL (United States)

    1995-05-01

    The Magnetically Assisted Chemical Separation (MACS) process combines the selectivity afforded by solvent extractants with magnetic separation by using specially coated magnetic particles to provide a more efficient chemical separation of transuranic (TRU) elements, other radionuclides, and heavy metals from waste streams. Development of the MACS process uses chemical and physical techniques to elucidate the properties of particle coatings and the extent of radiolytic and chemical damage to the particles, and to optimize the stages of loading, extraction, and particle regeneration. This report describes the development of a separation process for TRU elements from various high-level waste streams. Polymer-coated ferromagnetic particles with an adsorbed layer of octyl(phenyl)-N,N-diisobutylcarbamoylmethylphosphine oxide (CMPO) diluted with tributyl phosphate (TBP) were evaluated for use in the separation and recovery of americium and plutonium from nuclear waste solutions. Due to their chemical nature, these extractants selectively complex americium and plutonium contaminants onto the particles, which can then be recovered from the solution by using a magnet. The partition coefficients were larger than those expected based on liquid[liquid extractions, and the extraction proceeded with rapid kinetics. Extractants were stripped from the particles with alcohols and 400-fold volume reductions were achieved. Particles were more sensitive to acid hydrolysis than to radiolysis. Overall, the optimization of a suitable NMCS particle for TRU separation was achieved under simulant conditions, and a MACS unit is currently being designed for an in-lab demonstration.

  8. Research on red mud treatment by a circulating superconducting magnetic separator.

    Science.gov (United States)

    Li, Yiran; Chen, Haoshu; Wang, Jun; Xu, Fengyu; Zhang, Weimin

    2014-01-01

    Red mud (RM) accumulated over the years and caused a serious environmental problem. Iron-rich fraction separation is a cost-effective way to reduce the amount of disposal RM. A circulating high-gradient superconducting magnetic separator was produced in this work. Steel wool was filled in the circulating boxes. The boxes were connected by two chains, which moved in and out the magnetic field by a drive motor. The efficiency of iron-rich RM separation by the superconducting magnetic separator was investigated. An amount of 25% (w/w) iron-rich RM fractions with a grade of 65% were separated from the 56% iron content raw RM. The parameters of the steel wool matrix were important in controlling the iron-rich RM magnetic separation. Finer steel wool increased the iron recovery ratio, but decreased the grade of the iron-rich RM concentrates. Microscopic photographs of the RM particles showed that opaque mineral particles were enriched in the collected RM. The particle size distributions of raw, concentrate and residue RM were measured. The increased particle size of concentrate RM implied that large particles were entrapped in the steel wool matrix. PMID:24701921

  9. Optimisation of magnetic separation: a case study for soil washing at a heavy metals polluted site.

    Science.gov (United States)

    Sierra, C; Martínez-Blanco, D; Blanco, Jesús A; Gallego, J R

    2014-07-01

    Sandy loam soil polluted with heavy metals (As, Cu, Pb and Zn) from an ancient Mediterranean Pb mining and metallurgy site was treated by means of wet high-intensity magnetic separation to remove some of the pollutants therein. The treated fractions were chemically analysed and then subjected to magnetic characterisation, which determined the high-field specific (mass), magnetic susceptibility (?) and the specific (mass) saturation magnetisation (?S), through isothermal remanent magnetisation (IRM) curves. From the specific values of ? and ?S, a new expression to assess the performance of the magnetic separation operation was formulated and verified by comparison with the results obtained by traditional chemical analysis. The magnetic study provided valuable information for the exhaustive explanation of the operation, and the deduced mathematical expression was found to be appropriate to estimate the performance of the separation operation. From these results we determined that magnetic soil washing was effective for the treatment of the contaminated soil, concentrating the majority of the heavy metals and peaking its separation capacity at 60% of the maximum output voltage. PMID:24418067

  10. High Temperature Superconducting Reciprocating Magnetic Separator Final Report

    Energy Technology Data Exchange (ETDEWEB)

    James F. Maguire

    2008-06-05

    In 2001, under DOE's Superconductivity Partnership Initiative (SPI), E. I. du Pont de Nemours & Co. (Dupont) was awarded a cost-share contract to build a fully functional full-scale model high temperature superconducting reciprocating magnet unit specifically designed for the koalin clay industry. After competitive bidding, American Superconductor (AMSC) was selected to provide the coil for the magnet. Dupont performed the statement of work until September 2004, when it stopped work, with the concurrence of DOE, due to lack of federal funds. DOE had paid all invoices to that point, and Dupont had provided all cost share. At this same time, Dupont determined that this program did not fit with its corporate strategies and notified DOE that it was not interesting in resuming the program when funding became available. AMSC expressed interest in assuming performance of the Agreement to Dupont and DOE, and in March 2005, this project was transferred to AMSC by DOE amendment to the original contract and Novation Agreement between AMSC and Dupont. Design drawings and some hardware components and subassemblies were transferred to AMSC. However, no funding was obligated by DOE and AMSC never performed work on the project. This report contains a summary of the work performed by Dupont up to the September 04 timeframe.

  11. Setting up High Gradient Magnetic Separation for combating eutrophication of inland waters.

    Science.gov (United States)

    Merino-Martos, A; de Vicente, J; Cruz-Pizarro, L; de Vicente, I

    2011-02-28

    To find new approaches to devise technologies for handling with eutrophication of inland waters is a global challenge. Separation of the P from water under conditions of continuous flow is proposed as an alternative and effective method. This work is based on using highly magnetic particles as the seeding adsorbent material and their later removal from solution by High Gradient Magnetic Separation (HGMS). Contrast to other methods based on batch conditions, large volumes of water can be easily handled by HGMS because of decreasing retention times. This study identifies the best working conditions for removing P from solution by investigating the effects of a set of four different experimental variables: sonication time, flow rate (as it determines the retention time of particles in the magnetic field), magnetic field strength and the iron (Fe) particles/P concentration ratio. Additionally, the change of P removal efficiency with time (build up effect) and the possibility of reusing magnetic particles were also studied. Our results evidenced that while flow rate does not significantly affect P removal efficiency in the range 0.08-0.36 mL s(-1), sonication time, magnetic field strength and the Fe particles/P concentration ratio are the main factors controlling magnetic separation process. PMID:21255924

  12. Particle Capture Efficiency in a Multi-Wire Model for High Gradient Magnetic Separation

    CERN Document Server

    Eisenträger, Almut; Griffiths, Ian M

    2014-01-01

    High gradient magnetic separation (HGMS) is an efficient way to remove magnetic and paramagnetic particles, such as heavy metals, from waste water. As the suspension flows through a magnetized filter mesh, high magnetic gradients around the wires attract and capture the particles, removing them from the fluid. We model such a system by considering the motion of a paramagnetic tracer particle through a periodic array of magnetized cylinders. We show that there is a critical Mason number (ratio of viscous to magnetic forces) below which the particle is captured irrespective of its initial position in the array. Above this threshold, particle capture is only partially successful and depends on the particle's entry position. We determine the relationship between the critical Mason number and the system geometry using numerical and asymptotic calculations. If a capture efficiency below 100% is sufficient, our results demonstrate how operating the HGMS system above the critical Mason number but with multiple separa...

  13. Low Energy Electron Diffraction Structural Analysis of Au(111)-(5x5)-7S

    Science.gov (United States)

    Ash, Stephanie; Caragiu, Mellita; McGuirk, Garry; Shin, Heekeun; Diehl, Renee

    2011-10-01

    The clean Au(111) surface is known to undergo several structural changes when exposed to adsorbates, in particular sulfur. As the sulfur coverage increases towards 1ML, the structure of the gold (111) surface has been observed to go through a range of changes as follows: unreconstructed (1x1), followed by a (5x5)-7S structure, then a (3x3)R30^o-S phase, and eventually an incommensurate ``complex'' phase. The current LEED study focuses on the intermediate Au(111)-(5x5)-7S phase. The 7 sulfur atoms in each unit cell are found to occupy fcc hollow sites. There is considerable rumpling of the sulfur adsorbed layer, as well as the top gold layers in the surface, which results in an average S-Au distance of 1.54±0.06å, followed by the next Au-Au average interlayer spacing of 2.37±0.01å. When comparing the latter value to the bulk interlayer spacing of clean gold, of 2.35å, a slight expansion is noticed. The results are compared to the structural information obtained by other studies of the same Au(111)-(5x5) phase.

  14. Recovery of iron from cyanide tailings with reduction roasting–water leaching followed by magnetic separation

    International Nuclear Information System (INIS)

    Highlights: ? Using reduction roasting–water leaching–magnetic separation method, the recovery of iron from cyanide tailings was optimized. ? The recovery of iron was highly depended on the water-leaching process after reduction roasting. ? The results suggest that the method can be effectively used for iron recovery, and the grade of magnetic concentrate and recovery rate can reach 59.11% and 75.12%, respectively. - Abstract: Cyanide tailing is a kind of solid waste produced in the process of gold extraction from gold ore. In this paper, recovery of iron from cyanide tailings was studied with reduction roasting–water leaching process followed by magnetic separation. After analysis of chemical composition and crystalline phase, the effects of different parameters on recovery of iron were chiefly introduced. Systematic studies indicate that the high recovery rate and grade of magnetic concentrate of iron can be achieved under the following conditions: weight ratios of cyanide tailings/activated carbon/sodium carbonate/sodium sulfate, 100:10:3:10; temperature, 50 °C; time, 60 min at the reduction roasting stage; the liquid to solid ratio is 15:1 (ml/g), leaching at 60 °C for 5 min and stirring speed at 20 r/min at water-leaching; exciting current is 2 A at magnetic separation. The iron grade of magnetic concentrate was 59.11% and the recovery ratio was 75.12%. The mineralography of cyanide tailings, roasted product, water-leached sample, magnetic concentrad sample, magnetic concentrate and magnetic tailings were studied by X-ray powder diffraction (XRD) technique. The microstructures of above products except magnetic tailings were also analyzed by scanning electron microscope (SEM) and energy disperse spectroscopy (EDS) to help understand the mechanism.

  15. Simulating Chiral Magnetic and Separation Effects with Spin-Orbit Coupled Atomic Gases

    CERN Document Server

    Huang, Xu-Guang

    2015-01-01

    The chiral magnetic and chiral separation effects---quantum-anomaly-induced electric current and axial current along an external magnetic field in parity-odd quark-gluon plasma---have received intense studies in the community of heavy-ion collision physics. We show that analogous effects occur in rotating trapped Fermi gases with Weyl-Zeeman spin-orbit coupling where the rotation plays the role of an external magnetic field. These effects can induce a mass quadrupole in the atomic cloud along the rotation axis which may be tested in future experiments. Similar effects also exist in rotating trapped Bose gases with Weyl-Zeeman spin orbit coupling. Our results suggest that the spin-orbit coupled atomic gases are potential simulators of the chiral magnetic and separation effects.

  16. Botryococcus braunii cells: ultrasound-intensified outdoor cultivation integrated with in situ magnetic separation.

    Science.gov (United States)

    Wang, Shi-Kai; Wang, Feng; Stiles, Amanda R; Guo, Chen; Liu, Chun-Zhao

    2014-09-01

    An integrated system combining ultrasound-intensified outdoor cultivation of Botryococcus braunii with in situ magnetic harvesting of the algal cells was developed. The algal cells were cultivated in 200 L plastic bag reactors, and seven five-minute ultrasonic treatments at a four-day interval using a fixed frequency of 40 kHz and a total power of 300 W improved algal cell biomass and hydrocarbon productivity. The algal cells were harvested using functional magnetic particles and a magnetic separator, and a recovery efficiency of 90% was obtained under continuous operation at a flow rate of 100mL/min using the in situ magnetic separation system. The overall production cost using the integrated system was US$ 25.14 per kilogram of B. braunii dry biomass. The system developed in this study provides a base for the industrial production of B. braunii. PMID:24998478

  17. Experiments with a magnetic separator for heavy recoil ions

    International Nuclear Information System (INIS)

    Using a triple-focusing (position and momentum), crescent-shaped separator for heavy recoil-ions different experiments were performed. The improvement consists in the enhancement of the transmission from 8% to 25% for 500 keV recoil ions from the reaction 238U(?, 3n)sup(239m)Pu. For sup(237m)Pu the electromagnetic decay of the 1.1 ?s shape isomer into the 82 ns shape isomer was searched for. The upper limit for gamma decay is 1.25 +- 1.25% for Esub(?) = 200 keV and for electron decay 0.29 +- 0.29% in comparison to isomeric fission. The upper limit for interband transitions is 2.5% (2 delta), from which the upper limit of the partial half-life for the electromagnetic decay of the 1.1 ?s isomer is calculated to 44 ?s. Due to the performed interpretation the spin difference between both isomers extends at least to ?I = 3. For sup(238m)U the back-decay into the 1. minimum by the EO-transition and the converted 2+ ? 0+ transition in the first decay and the decay by alpha articles was looked for both in single measurements as in a coincidence measurement to L-X-ray quanta. The upper limits are GAMMAsub(EO) = 2.0, GAMMAsub(?)/GAMMAsub(F) = 0.4 and GAMMA(back-decay)/GAMMAsub(F) approx. equal to 100. (orig./HSI)

  18. Separation of Variables in the Classical Integrable SL(3) Magnetic Chain

    OpenAIRE

    Sklyanin, E. K.

    1992-01-01

    There are two fundamental problems studied by the theory of hamiltonian integrable systems: integration of equations of motion, and construction of action-angle variables. The third problem, however, should be added to the list: separation of variables. Though much simpler than two others, it has important relations to the quantum integrability. Separation of variables is constructed for the $SL(3)$ magnetic chain --- an example of integrable model associated to a nonhyperel...

  19. Double Exchange Model at Low Densities: Magnetic Polarons and Coulomb Suppressed Phase Separation

    OpenAIRE

    Pereira, Vitor M.; Santos, J. M. B. Lopes dos; Neto, Antonio H. Castro

    2008-01-01

    We consider the double exchange model at very low densities. The conditions for the formation of self-trapped magnetic polarons are analyzed using an independent polaron model. The issue of phase separation in the low density region of the temperature-density phase diagram is discussed. We show how electrostatic and localization effects can lead to the substantial suppression of the phase separated regime. By examining connections between the resulting phase and the polaroni...

  20. Absence of magnetic phase separation in MnSi under pressure

    OpenAIRE

    Andreica, D.; Reotier, P. Dalmas; Yaouanc, A.; Amato, A.; Lapertot, G.

    2010-01-01

    We report muon spin spectroscopy data (muSR) obtained under hydrostatic pressure on a large single crystal of the itinerant helimagnet MnSi, and recorded down to 0.235 K and up to 15.1 kbar. Up to the critical pressure p_c = 14.9 (2) kbar, where the magnetic order is suppressed, the muSR data unambiguously demonstrate that the ground state of the system is magnetic with no indication of any phase separation.

  1. Two-dimensional plasma expansion in a magnetic nozzle: Separation due to electron inertia

    OpenAIRE

    Ahedo Galilea, Eduardo; Merino, Mario

    2012-01-01

    A previous axisymmetric model of the supersonic expansion of a collisionless, hot plasma in a divergent magnetic nozzle is extended here in order to include electron-inertia effects. Up to dominant order on all components of the electron velocity, electron momentum equations still reduce to three conservation laws. Electron inertia leads to outward electron separation from the magnetic streamtubes. The progressive plasma filling of the adjacent vacuum region is consistent with electron-inerti...

  2. Optimized high gradient magnetic separation for isolation of Plasmodium-infected red blood cells

    OpenAIRE

    Chimma Pattamawan; Pannadaporn Peeranad; Sratongno Panudda; Somsri Sangdao; Ottinger Annette; Bhakdi Sebastian C; Malasit Prida; Pattanapanyasat Kovit; Ph, Neumann Hartmut

    2010-01-01

    Abstract Background Highly purified infected red blood cells (irbc), or highly synchronized parasite cultures, are regularly required in malaria research. Conventional isolation and synchronization rely on density and osmotic fragility of irbc, respectively. High gradient magnetic separation (HGMS) offers an alternative based on intrinsic magnetic properties of irbc, avoiding exposure to chemicals and osmotic stress. Successful HGMS concentration in malaria research was previously reported us...

  3. Theoretical and Experimental Study of the Magnetic Separation of Pollutants from Wastewater

    OpenAIRE

    Mariani, Giacomo

    2010-01-01

    This Thesys reports the study of a HGMS (High GradientMagnetic Separation) process for the treatment of industrialwastewaters that considers an assisted chemical-physical pre-treatment for the removal of heavy metals through the bound by adsorption with added iron-oxide particulate matter (hematite). The considered filter, constituted by ferromagnetic stainless steel wool and permanent magnets, is studied with a new approach based on a statistical analysis that requires the study of the traje...

  4. Magselectofection: A novel integrated technology of magnetic separation and genetic modification of target cells

    OpenAIRE

    Sanchez Antequera, Yolanda

    2010-01-01

    Research applications and cell therapies involving genetically modified cells require reliable, standardized and cost-effective methods for cell manipulation. The goal of this work is to provide a novel methodology that produces, in a single standardized techonology, genetic modification and cell isolation. We have named this novel procedure ?Magselectofection”. The approach is based on magnetic cell separation and magnetically-guided gene delivery (magnetofection). Optimized gene vectors...

  5. Quantification of Non-Specific Binding of Magnetic Micro and Nano particles using Cell Tracking Velocimetry: Implication for magnetic cell separation and detection

    OpenAIRE

    Chalmers, J. J.; Xiong, Y.; Jin, X.; Shao, M.; Tong, X.; Farag, S.; Zborowski, M.

    2010-01-01

    The maturation of magnetic cell separation technology places increasing demands on magnetic cell separation performance. While a number of factors can cause suboptimal performance, one of the major challenges can be non-specific binding of magnetic nano or micro particles to non-targeted cells. Depending on the type of separation, this non-specific binding can have a negative effect on the final purity, the recovery of the targeted cells, or both. In this work, we quantitatively demonstrate t...

  6. High gradient magnetic particle separation in viscous flows by 3D BEM

    Science.gov (United States)

    Ravnik, J.; Hriberšek, M.

    2013-04-01

    The boundary element method was applied to study the motion of magnetic particles in fluid flow under the action of external nonuniform magnetic field. The derived formulation combines the velocity-vorticity resolved Navier-Stokes equations with the Lagrange based particle tracking model, where the one-way coupling with fluid phase was considered. The derived algorithm was used to test a possible design of high gradient magnetic separation in a narrow channel by computing particles trajectories in channel flow under the influence of hydrodynamic and magnetic forces. Magnetic field gradient was obtained by magnetization wires placed outside of the channel. Simulations with varying external magnetic field and flow rate were preformed in order to asses the collection efficiency of the proposed device. We found that the collection efficiency decreases linearly with increasing flow rate. Also, the collection efficiency was found to increase with magnetic field strength only up a saturation point. Furthermore, we found that high collection efficiently is not feasible at high flow velocity and/or at weak magnetic field. Recommendation for optimal choice of external magnetic field and flow rate is discussed.

  7. Trapped Noble Gases in Magnetic and Non-Magnetic Separates from Allende Chondrules: Clues for Noble Gas Fractionation during Chondrule Formation

    Science.gov (United States)

    Das, J. P.; Meshik, A. P.; Pravdivtseva, O.; Hohengberg, C. M.

    2012-03-01

    Magnetic (M) and non-magnetic (NM) phases were separated from big and small chondrules from Allende. M phases carry higher trapped noble gases, suggesting fractionation of noble gas during chondrule formation. Also, big chondrules are less homogenized.

  8. Efficiency comparison of two preparative mechanisms for magnetic separation of erythrocytes from whole blood

    Science.gov (United States)

    Graham, M. D.

    1981-03-01

    Separation efficiencies of erythrocytes, made paramagnetic by oxidation of their cellular oxyhemoglobin to methemoglobin with sodium nitrite, were compared under identical magnetic separation conditions with those of cells whose oxyhemoglobin had been reduced to deoxyhemoglobin through exposure to sodium dithionite, and the percentage of high-spin hemoglobin was estimated spectrophotometrically. Both parallel and transverse flow/matrix filter configurations gave greater average separation efficiencies, with less variability, for erythrocytes containing the dithionite-reduced hemoglobin. These findings are thought to originate in the characteristics of the oxidative reaction, since the spectrophotometric data indicate a similar variability in oxidation of oxyhemoglobin to methemoglobin.

  9. Magnetic separation as an adjunct to surface barrier detectors for backscattering and ion reaction analysis methods

    International Nuclear Information System (INIS)

    The sensitivity of analysis by energy spectroscopy of product ions using solid state detectors is often limited by instrumental background from pulse pileup, due to an intense flux of lower energy ions scattered from the accelerator beam. A small magnet can be used for low resolution separation of ions of different type and/or energy. In the present work a simple permanent magnet is used to reject ions of low magnetic rigidity. The technique has been developed for the depth profiling of oxygen in solar absorber surfaces using the 18O(p,?) reaction, and to determine surface trces of gold on silicon substrates

  10. Design of large aperture superferric quadrupole magnets for an in-flight fragment separator

    Energy Technology Data Exchange (ETDEWEB)

    Zaghloul, Aziz; Kim, Dogyun; Kim, Jangyoul; Kim, Mijung; Kim, Myeongjin; Yun, Chongcheoul; Kim, Jongwon [Rare Isotope Science Project, Institute for Basic Science, Yuseong, Daejeon, 305-811 (Korea, Republic of)

    2014-01-29

    Superferric quadrupole magnets to be used for in-flight fragment separator have been designed. A quadrupole magnet triplet for beam focusing is placed in a cryostat together with superconducting correction coils. To maximize acceptance of rare isotope beams produced by projectile fragmentation, it is essential to use large-aperture quadrupole magnets. The pole tip radius is 17 cm in the current design, and we tried to enlarge the aperture with 3D analysis on magnetic fields. In the front end of the separator, where a target and beam dump are located, we plan to use two sets of quadrupole triplets made of high-Tc superconductor (HTS) operating at 20-50 K considering high radiation heat load. The HTS magnet will use warm iron poles. Both low-Tc and high-Tc superconductors are acquired for test winding, and two kinds of dewar and cryostat are under construction to perform the coil and magnet tests. The magnetic design of superferric quadrupole is mainly discussed.

  11. Design of large aperture superferric quadrupole magnets for an in-flight fragment separator

    Science.gov (United States)

    Zaghloul, Aziz; Kim, Dogyun; Kim, Jangyoul; Kim, Mijung; Kim, Myeongjin; Yun, Chongcheoul; Kim, Jongwon

    2014-01-01

    Superferric quadrupole magnets to be used for in-flight fragment separator have been designed. A quadrupole magnet triplet for beam focusing is placed in a cryostat together with superconducting correction coils. To maximize acceptance of rare isotope beams produced by projectile fragmentation, it is essential to use large-aperture quadrupole magnets. The pole tip radius is 17 cm in the current design, and we tried to enlarge the aperture with 3D analysis on magnetic fields. In the front end of the separator, where a target and beam dump are located, we plan to use two sets of quadrupole triplets made of high-Tc superconductor (HTS) operating at 20-50 K considering high radiation heat load. The HTS magnet will use warm iron poles. Both low-Tc and high-Tc superconductors are acquired for test winding, and two kinds of dewar and cryostat are under construction to perform the coil and magnet tests. The magnetic design of superferric quadrupole is mainly discussed.

  12. Analysis of phase separation by thermal aging in duplex stainless steels by magnetic methods

    Energy Technology Data Exchange (ETDEWEB)

    Kim, S. K.; Jae, W. M.; Kim, Y. S. [Hanyang Univ., Seoul (Korea, Republic of)

    1997-10-01

    The phase separation in ferrite phase of duplex stainless steel is the primary cause of thermal aging embrittlement of the LWR primary pressure boundary components. In this study the phase separation of simulated duplex stainless steel was detected by Mossbauer spectroscopy and magnetic property analysis by VSM (Vibrating Specimen Magnetometer). The simulated duplex stainless steels, Fe-Cr binary, Fe-Cr-Ni Temary, and Fe-Cr-Ni-Si quaternary alloys, were aged at 370 and 400 deg C up to 5,340 hours. It was observed from Mossbauer spectra analysis that internal magnetic field increases with aging time and from VSM that the specific saturation magnetization and Curie temperature increase with aging time. These results are indicative that phase separation into Fe-rich region and Cr-rich region is caused by thermal aging in the temperature range of 370 - 400 deg C. In cases specimens containing Ni, the increase of specific saturation magnetization is much higher. This implies that Ni seems to promote Fe-Cr interdiffusion, which accelerates the phase separation into Fe-rich {alpha} phase and Cr-rich {alpha}` phase. (author).

  13. Analysis of phase separation by thermal aging in duplex stainless steels by magnetic methods

    International Nuclear Information System (INIS)

    The phase separation in ferrite phase of duplex stainless steel is the primary cause of thermal aging embrittlement of the LWR primary pressure boundary components. In this study the phase separation of simulated duplex stainless steel was detected by Mossbauer spectroscopy and magnetic property analysis by VSM (Vibrating Specimen Magnetometer). The simulated duplex stainless steels, Fe-Cr binary, Fe-Cr-Ni Temary, and Fe-Cr-Ni-Si quaternary alloys, were aged at 370 and 400 deg C up to 5,340 hours. It was observed from Mossbauer spectra analysis that internal magnetic field increases with aging time and from VSM that the specific saturation magnetization and Curie temperature increase with aging time. These results are indicative that phase separation into Fe-rich region and Cr-rich region is caused by thermal aging in the temperature range of 370 - 400 deg C. In cases specimens containing Ni, the increase of specific saturation magnetization is much higher. This implies that Ni seems to promote Fe-Cr interdiffusion, which accelerates the phase separation into Fe-rich ? phase and Cr-rich ?' phase. (author)

  14. Separation of electrostatic and magnetic phase shifts using a modified transport-of-intensity equation

    International Nuclear Information System (INIS)

    We introduce a new approach for the separation of the electrostatic and magnetic components of the electron wave phase shift, based on the transport-of-intensity equation (TIE) formalism. We derive two separate TIE-like equations, one for each of the phase shift components. We use experimental results on FeCoB and Permalloy patterned islands to illustrate how the magnetic and electrostatic longitudinal derivatives can be computed. The main advantage of this new approach is the fact that the differences in the power spectra of the two phase components (electrostatic phase shifts often have significant power in the higher frequencies) can be accommodated by the selection of two different Tikhonov regularization parameters for the two phase reconstructions. The extra computational demands of the method are more than compensated by the improved phase reconstruction results. - Highlights: • We provide a new way to separate electrostatic and magnetic phase shifts in Lorentz microscopy. • We derive two new transport-of-intensity style equations, one for electrostatic phase shifts and the other for magnetic phase shifts. • We provide a new way to determine the longitudinal intensity derivative that automatically includes time reversal symmetry. • This approach allows for the Tikhonov regularization parameter to be selected for each phase shift separately. • We provide two example application on Permalloy and CoFeB patterned islands

  15. Nuclear charge and isobar separation in a gas-filled enge split-pole magnetic spectrograph

    International Nuclear Information System (INIS)

    The sepration technique is based on the fact that charge-changing processes of an ion in a gas, if they occur frequently enough in a magnetic field region, lead to trajectories determined by the average charge state of the ion in the gas. The technique has been used to separate isobaric 58Ni and 58Fe ions. 7 refs., 4 figs., 1 tab

  16. Separation of flow from chiral magnetic effect in U+U collisions using spectator asymmetry

    CERN Document Server

    Chatterjee, Sandeep

    2014-01-01

    We demonstrate that the prolate shape of the Uranium nucleus generates anti-correlation between spectator asymmetry and initial state ellipticity of the collision zone, providing a way to constrain the initial event shape in U+U collisions. As an application, we show that this can be used to separate the background contribution due to flow from the signals of chiral magnetic effect.

  17. APPLICATION OF HIGH-GRADIENT MAGNETIC SEPARATION TO FINE PARTICLE CONTROL

    Science.gov (United States)

    The report gives results of an assessment of the potential use of high-gradient magnetic separation (HGMS) as a means of collecting gas stream particulates. The assessment included both experiments and analyses of theoretical models. Phase I included evaluations of theoretical ex...

  18. Superconducting open-gradient magnetic separation for the pretreatment of radioactive or mixed waste vitrification feeds. 1998 annual progress report

    International Nuclear Information System (INIS)

    'The objective is to reduce the volume and cost of high-level waste glass produced during US DOE remediation activities by demonstrating that magnetic separation can separate crystalline, amorphous, and colloidal constituents in vitrification feed streams known to be deleterious to the production of borosilicate glass. Magnetic separation will add neither chemicals nor generate secondary waste streams. The project includes the systematic study of magnetic interactions of waste constituents under controlled physical and chemical conditions (e.g., hydration, oxidation, temperature) to identify mechanisms that control the magnetic properties. Partitioning of radionuclides to determine their sorption mechanisms is also being studied. The identification of fundamental magnetic properties within the microscopic chemical environment in combination with hydrodynamic and electrodynamic models provides insights into the design of a system for optimal separation. Following this, experimental studies using superconducting open-gradient magnetic separation (OGMS) will be conducted to validate its effectiveness as a pretreatment technique.'

  19. Mass-separation of impurities in the ion beam systems with reversed magnetic beam focusing

    International Nuclear Information System (INIS)

    This paper describes the intrinsic capability of ion systems with reversed magnetic beam focusing for impurities mass-separation. Numerical calculation of the ion trajectory deviation with taking into account the experimental ion energy distribution function for hydrogen-oxygen gas mixture was carried out. It is demonstrated that O+ impurities which are present in the beam are separated and form the circle with a diameter of ?6 mm. Therefore, the central part of the spot is free of impurities due to magnetic separation. As a result, the source generates steady-state hydrogen ion beam, which irradiates the surface with high heat and particle fluxes, which approach the upper limit for the flux range expected in a fusion reactor.

  20. Thickness effect on magnetic and electronic response in phase separated manganite thin films

    Science.gov (United States)

    Jeen, Hyoung Jeen; Biswas, Amlan

    2015-03-01

    Thickness variation can be used to observe confinement effects and to control the strain state of thin films. Such confinement and strain state variation often creates unconventional physical properties in thin films of complex oxides such as phase separated (La1 - yPry)0.67Ca0 . 33MnO3 (LPCMO). Thin films of LPCMO show physical properties different from bulk samples such as, in-plane magnetic anisotropy and strain-driven anisotropic dynamic percolation. In this presentation, we will show the relation between lattice strain and the formation of an antiferromagnetic charge ordered insulating phase and the effect of strain relaxation on the magnetic anisotropy and single domain to multi-domain transition in electronically phase separated LPCMO thin films. We observed an increase in residual resistivity, a reduction of in-plane magnetic anisotropy, and an increase of the domain transition temperature as the thickness of the thin films is increased. NSF DMR 1410237.

  1. Selection of a matrix for the recovery of uranium by wet high-intensity magnetic separation

    Energy Technology Data Exchange (ETDEWEB)

    Svoboda, J.

    1985-05-30

    The concentration, by wet high-intensity magnetic separation (WHIMS), of gold and uranium in materials resulting from the cyanidation of Witwatersrand ores was tested on an industrial scale on two South African gold mines, and the results are discussed in detail. The mechanical and metallurgical performance of the carousel magnetic separators was found to be satisfactory, but, for the large-scale application of WHIMS in the South African mining industry, a more cost-effective machine is required. It was decided that, in the present work, the information contained in several unpublished internal Mintek communications should be summarized and used as guidelines in the selection of matrices that would be suitable for the recovery of finely dispersed, weakly magnetic minerals.

  2. Removal of less biodegradable dissolved organic matters in water by superconducting magnetic separation with magnetic mesoporous carbon

    Science.gov (United States)

    Kondo, K.; Jin, T.; Miura, O.

    2010-11-01

    Less biodegradable dissolved organic matters in water as typified by humic substances are known as precursors of carcinogenic trihalomethanes, and are removed about 60% by current advanced water treatments. However, further increase of the removal ratio is demand. In this study, magnetic mesoporous carbon (MMPC), which can adsorb the substances physically and be efficiently collected by using superconducting high gradient magnetic separation (HGMS), has been synthesized with coconut-shell-based activated carbon and ferric nitrate solution by the gas activation method. The MMPC has the maximum magnetization value of 30.7 emu/g and an adsorption ability of 87% to 10 mg/L humic acid in a short time. The standard MMPC having a magnetization of 6.43 emu/g was able to be separated at magnetic field of 2 T. Used MMPC regained the adsorption ability to 93.1% by N 2 reactivation heat treatment. These results show promise for application of current water treatments by superconducting HGMS, which is suitable for high-speed water treatment without secondary wastes.

  3. Removal of less biodegradable dissolved organic matters in water by superconducting magnetic separation with magnetic mesoporous carbon

    International Nuclear Information System (INIS)

    Less biodegradable dissolved organic matters in water as typified by humic substances are known as precursors of carcinogenic trihalomethanes, and are removed about 60% by current advanced water treatments. However, further increase of the removal ratio is demand. In this study, magnetic mesoporous carbon (MMPC), which can adsorb the substances physically and be efficiently collected by using superconducting high gradient magnetic separation (HGMS), has been synthesized with coconut-shell-based activated carbon and ferric nitrate solution by the gas activation method. The MMPC has the maximum magnetization value of 30.7 emu/g and an adsorption ability of 87% to 10 mg/L humic acid in a short time. The standard MMPC having a magnetization of 6.43 emu/g was able to be separated at magnetic field of 2 T. Used MMPC regained the adsorption ability to 93.1% by N2 reactivation heat treatment. These results show promise for application of current water treatments by superconducting HGMS, which is suitable for high-speed water treatment without secondary wastes.

  4. Measurement of the adhesion force between particles for high gradient magnetic separation of pneumatic conveyed powder products

    Science.gov (United States)

    Senkawa, K.; Nakai, Y.; Mishima, F.; Akiyama, Y.; Nishijima, S.

    2011-11-01

    In the industrial plants such as foods, medicines or industrial materials, there are big amount of issues on contamination by metallic wear debris originated from pipes of manufacturing lines. In this study, we developed a high gradient magnetic separation system (HGMS) under the dry process by using superconducting magnet to remove the ferromagnetic particles. One of the major problems of dry HGMS systems is, however, the blockage of magnetic filter caused by particle coagulation or deposition. In order to actualize the magnetic separation without blockage, we introduced pneumatic conveyance system as a new method to feed the powder. It is important to increase the drag force acting on the sufficiently dispersed particles, which require strong magnetic fields. To generate the strong magnetic fields, HGMS technique was examined which consists of a magnetic filter and a superconducting solenoid magnet. As a result of the magnetic separation experiment, it was shown that the separation efficiency changes due to the difference of the cohesive property of the particles. On the basis of the result, the adhesion force which acts between the ferromagnetic particles and the medium particles used for the magnetic separation was measured by Atomic Force Microscope (AFM), and cohesion of particles was studied from the aspect of interparticle interaction. We assessed a suitable flow velocity for magnetic separation according to the cohesive property of each particle based on the result.

  5. Measurement of the adhesion force between particles for high gradient magnetic separation of pneumatic conveyed powder products

    International Nuclear Information System (INIS)

    In the industrial plants such as foods, medicines or industrial materials, there are big amount of issues on contamination by metallic wear debris originated from pipes of manufacturing lines. In this study, we developed a high gradient magnetic separation system (HGMS) under the dry process by using superconducting magnet to remove the ferromagnetic particles. One of the major problems of dry HGMS systems is, however, the blockage of magnetic filter caused by particle coagulation or deposition. In order to actualize the magnetic separation without blockage, we introduced pneumatic conveyance system as a new method to feed the powder. It is important to increase the drag force acting on the sufficiently dispersed particles, which require strong magnetic fields. To generate the strong magnetic fields, HGMS technique was examined which consists of a magnetic filter and a superconducting solenoid magnet. As a result of the magnetic separation experiment, it was shown that the separation efficiency changes due to the difference of the cohesive property of the particles. On the basis of the result, the adhesion force which acts between the ferromagnetic particles and the medium particles used for the magnetic separation was measured by Atomic Force Microscope (AFM), and cohesion of particles was studied from the aspect of interparticle interaction. We assessed a suitable flow velocity for magnetic separation according to the cohesive property of each particle based on the ve property of each particle based on the result.

  6. Gravitational and magnetic separation in self-assembled clay-ferrofluid nanocomposites

    Scientific Electronic Library Online (English)

    F.L.O., Paula; G.J. da, Silva; R., Aquino; J., Depeyrot; J.O., Fossum; K.D., Knudsen; G., Helgesen; F.A., Tourinho.

    2009-04-01

    Full Text Available We report on experimental observations of self-assemblies in colloidal dispersions of clay nanoplatelets and magnetic nanoparticles. Visual observations have been combined with small angle X-ray scattering (SAXS) in the study of several composites at a fixed clay concentration in the dilute regime, [...] and varying ferrofluid concentrations. Our visual observations which encompass macroscopic separation in gravitational- and magnetic field, indicate that all samples present a concentrated phase and a diluted one. SAXS data obtained from each phase are consistent with the interpretation that the scattering contribution from the clay nano-platelets in the samples can be neglected in comparison with the magnetic particle contribution. The analysis of the scattered intensity is performed combining two models, one based on the global scattering function and the other allowing the extraction of the structure factor of the mixtures. The parameters of the size distribution of magnetic nanoparticles determined by both methods are in good agreement. The structure factor of the mixtures shows that on a local scale, the mixtures behave like a gas of isolated magnetic nanoparticles. It also indicates the presence of interactions between magnetic nanoparticles mediated by the presence of Laponite platelets. Such interactions could be attributed with a progressive partial phase separation between spheres and discs rather than to the formation of dense aggregates.

  7. Immunomagnetic separation of Salmonella with tailored magnetic micro and nanocarriers. A comparative study.

    Science.gov (United States)

    Brandão, Delfina; Liébana, Susana; Campoy, Susana; Alegret, Salvador; Isabel Pividori, María

    2015-10-01

    This paper addresses a comparative study of immunomagnetic separation of Salmonella using micro and nano-sized magnetic carriers. In this approach, nano (300nm) and micro (2.8?m) sized magnetic particles were modified with anti-Salmonella antibody to pre-concentrate the bacteria from the samples throughout an immunological reaction. The performance of the immunomagnetic separation on the different magnetic carriers was evaluated using classical culturing, confocal and scanning electron microscopy to study the binding pattern, as well as a magneto-actuated immunosensor with electrochemical read-out for the rapid detection of the bacteria in spiked milk samples. In this approach, a second polyclonal antibody labeled with peroxidase as electrochemical reporter was used. The magneto-actuated electrochemical immunosensor was able to clearly distinguish between food pathogenic bacteria such as Salmonella enterica and Escherichia coli, showing a limit of detection (LOD) as low as 538CFUmL(-1) and 291CFUmL(-1) for magnetic micro and nanocarriers, respectively, in whole milk, although magnetic nanoparticles showed a noticeable higher matrix effect and higher agglomeration effect. These LODs were achieved in a total assay time of 1h without any previous culturing pre-enrichment step. If the samples were pre-enriched for 8h, the magneto immunosensor based on the magnetic nanoparticles was able to detect as low as 1CFU in 25mL of milk (0.04CFUmL(-1)). PMID:26078149

  8. High-gradient magnetic affinity separation of trypsin from porcine pancreatin

    DEFF Research Database (Denmark)

    Hubbuch, Jürgen; Thomas, Owen R. T.

    2002-01-01

    We introduce a robust and scale-flexible approach to macromolecule purification employing tailor-made magnetic adsorbents and high-gradient magnetic separation technology adapted from the mineral processing industries. Detailed procedures for the synthesis of large quantities of low-cost defined submicron-sized magnetic supports are presented. These support materials exhibit unique features, which facilitate their large-scale processing using high magnetic field gradients, namely sufficiently high magnetization, a relatively narrow particle size distribution and ideal superparamagnetism. Following systematic optimization with respect to activation chemistry, spacer length and ligand density, conditions for preparation of effective high capacity (Q(max) = 120 mg g(-1)) strongly interacting (K-d <0.3 mum) trypsin-binding adsorbents based on immobilized benzamidine were established. In small-scale studies approximate to95% of the endogenous trypsin present in a crude porcine pancreatin feedstock was recovered with a purification factor of approximate to4.1 at the expense of only a 4% loss in a-amylase activity. Efficient recovery of trypsin from the same feedstock was demonstrated at a vastly increased scale using a high-gradient magnetic separation system to capture loaded benzamidine-linked adsorbents following batch adsorption. With the aid of a simple recycle loop over 80% of the initially adsorbed trypsin was recovered in-line with an overall purification factor of approximate to3.5.

  9. Magnetic separation for pre-concentration of uranium values from copper plant tailings

    International Nuclear Information System (INIS)

    Using the paramagnetic character of uranium minerals, the preconcentration of uranium bearing ores and copper plant tailings of Singhbhum area have been investigated in a pilot plant scale wet high intensity magnetic separator (WHIMS). The variables studied include magnetic field intensity, matrix drum speed feed slurry flow rate and its pulp density. The results of these investigations have shown that 75-85% of the contained uranium values could be recovered in 45-55% weight in the magnetic fraction in the case of copper plant tailings from Rakha, Surda and Mosabani. The losses in the non magnetics were primarily due to the ultrafine liberated uraninite particles not collected by WHIMS due to machine limitations and the values occurring as fine inclusions in quartz. Improved recovery can be obtained by offering higher field gradients and preventing loss of very fine liberated uranium values. High gradient magnetic separator (HGMS) offers higher field gradients. A test sample of Mosabani copper tailings studied at the Sala Magnetic Inc in HGMS has indicated superior results in comparison to WHIMS. (author). 7 refs., 3 figs., 6 tabs

  10. A comprehensive in vitro investigation of a portable magnetic separator device for human blood detoxification

    International Nuclear Information System (INIS)

    A portable magnetic separator device is being developed for a proposed magnetically based detoxification system. In this paper, the performance of this device was evaluated via preliminary in vitro flow experiments using simple fluids and a separator unit consisting of one tube and two metal wires, each at the top and bottom of the tube. The effects of the following factors were observed: mean flow velocity Uo (0.14-45 cm s-1), magnetic field strength ?oHo (0.125-0.50 T), wire size Rw (0.125, 0.250 and 0.500 mm), wire length Lw (2, 5 and 10 cm), wire materials (nickel, stainless steel 304 and 430) and tube size (outer radius Ro = 0.30 mm and inner radius Ri = 0.25 mm; Ro = 0.50 mm and Ri = 0.375 mm; and Ro = 2.0 mm and Ri = 1.0 mm). Our observations showed that the experimental results fit well with the corresponding theoretical results from the model we previously developed at a low flow velocity area (for example, Uo ? 20 cm s-1), strong external magnetic field (for example, ?0.30 T) and long wire length (for example, Lw = 10 cm). The experimental results also showed that more than 90% capture efficiency is indeed achievable under moderate systemic and operational conditions. Pressure drop measurements revealed that the device could work well under human physiological and clinical conditions, and spgical and clinical conditions, and sphere buildup would not have any considerable effect on the pressure drop of the device. The breakthrough experiments demonstrated that a lower flow rate V, higher applied magnetic field ?oHo and diluted sphere suspension, i.e. lower Co, would delay the breakthrough. All the results indicate the promise of this portable magnetic separator device to efficiently in vivo sequestrate nano-/micro-spheres from blood flow in the future magnetically based detoxification system

  11. High gradient magnetic separation of upconverting lanthanide nanophosphors based on their intrinsic paramagnetism

    International Nuclear Information System (INIS)

    Photon upconverting nanophosphors (UCNPs) have the unique luminescent property of converting low-energy infrared light into visible emission which can be widely utilized in nanoreporter and imaging applications. For the use as reporters in these applications, the UCNPs must undergo a series of surface modification and bioconjugation reactions. Efficient purification methods are required to remove the excess reagents and biomolecules from the nanophosphor solution after each step to yield highly responsive reporters for sensitive bioanalytical assays. However, as the particle size of the UCNPs approaches the size of biomolecules, the handling of these reporters becomes cumbersome with traditional purification methods such as centrifugation. Here we introduce a novel approach for purification of bioconjugated 32-nm NaYF4: Yb3+, Er3+-nanophosphors from excess unbound biomolecules utilizing high gradient magnetic separation (HGMS)-system constructed from permanent super magnets which produce magnetic gradients in a magnetizable steel wool matrix amplifying the magnetic field. The non-magnetic biomolecules flowed straight through the magnetized HGMS-column while the UCNPs were eluted only after the magnetic field was removed. In the UCNPs the luminescent centers, i.e., lanthanide-ion dopants are responsible for the strong upconversion luminescence, but in addition they are also paramagnetic. In this study we have shown that the presence of these weakly paramagnetic luminescent lanthanides actually also enables the use of HGMS to capture the UCNPs without incorporating additional optically inactive magnetic core into them

  12. High gradient magnetic separation YBCO particles in a gas-fluidized bed

    International Nuclear Information System (INIS)

    In this paper, high gradient magnetic separation of copper-oxide superconducting particles in a gas-fluidized bed is studied experimentally. Particles over the size range 45-105 ?m exhibit classical behavior when fluidized with He gas at 77 K, whereas the more cohesive, smaller particles were difficult to fluidize. Separation experiments on a uniform mixture of tetragonal and orthorhombic phases have shown that 30 min of exposure to the field gradient is sufficient to equilibrate the superconductor concentration profile. In addition, the equilibrium separation data reveal that best separation is achieved at three times the minimum fluidization gas velocity Umf. This is consistent with the behavior of fine powders where the interparticle frictional forces are minimized at 3 Umf. Observed results are discussed in terms of a collective effect of Meissner and interparticle friction

  13. Separation Nanotechnology of Diethylenetriaminepentaacetic Acid Bonded Magnetic Nanoparticles for Spent Nuclear Fuel

    International Nuclear Information System (INIS)

    A nanomagnetic separation method based on Diethylenetriaminepentaacetic acid (DTPA) conjugated with magnetic nanoparticles (MNPs) is studied for application in spent nuclear fuel separation. The high affinity of DTPA towards actinides aids in separation from the highly acidic medium of nuclear waste. The solubility and magnetization of particles at low pH is protected by encapsulating them in silica layer. Surface functionalization of silica coated particles with polyamines enhances the loading capacity of the chelators on MNPs. The particles were characterized before and after surface modification using transmission electron microscopy (TEM), helium ion microscopy (HIM), Fourier transform-infrared (FT-IR) spectrometry, and X-ray diffractometry. The coated and uncoated samples were studied using vibrating sample magnetometer (VSM) to understand the change in magnetic properties due to the influence of the surface functionalization. The hydrodynamic size and surface charge of the particles are investigated using Dynamic Light Scattering (DLS). The uptake behavior of Am(III), Pu(IV), U(VI), and Np(V) from 0.1M NaNO3 solution was investigated. The sorption result shows the strong affinity of DTPA towards Am(III) and Pu(IV) by extracting 97% and 80% of actinides, respectively. The high removal efficiency and fast uptake of actinides make the chelator conjugated MNPs an effective method for spent nuclear fuel separation.

  14. Challenge to the volume reduction of contaminated soil based on magnetic separation

    International Nuclear Information System (INIS)

    A great amount of radioactive substances were released in the neighborhood of Fukushima Daiichi Nuclear Power Station following the accident of this plant. In particular, damage from radioactive cesium (134 or 137) has become the main case of trouble, incurring the necessity of decontamination of soil in the contaminated territory. In addition, a large amount of contaminated soil was generated due to the decontamination work, and its volume reduction has become a large challenge for the management and storage. This paper takes up magnetic separation technology as one of the technologies of volume reduction, and introduces its development condition. In this method, soil is firstly classified by size, and clay (or silt) with small particles, which adsorbs about 80% of radioactive cesium in soil, is separated from sand gravel. Furthermore, this clay portion is separated based on magnetic separation to 1:1 type and 1:2 type clay minerals with different magnetic susceptibilities, for the purpose of volume reduction. This paper describes the principle of the above method, as well as the development history to date. (A.O.)

  15. A simple and rapid harvesting method for microalgae by in situ magnetic separation.

    Science.gov (United States)

    Xu, Ling; Guo, Chen; Wang, Feng; Zheng, Sen; Liu, Chun-Zhao

    2011-11-01

    A simple and rapid harvesting method by in situ magnetic separation with naked Fe(3)O(4) nanoparticles has been developed for the microalgal recovery of Botryococcus braunii and Chlorella ellipsoidea. After adding the magnetic particles to the microalgal culture broth, the microalgal cells were adsorbed and then separated by an external magnetic field. The maximal recovery efficiency reached more than 98% for both microalgae at a stirring speed of 120 r/min within 1 min, and the maximal adsorption capacity of these Fe(3)O(4) nanoparticles reached 55.9 mg-dry biomass/mg-particles for B. braunii and 5.83 mg-dry biomass/mg-particles for C. ellipsoidea. Appropriate pH value and high nanoparticle dose were favorable to the microalgae recovery, and the adsorption mechanism between the naked Fe(3)O(4) nanoparticles and the microalgal cells was mainly due to the electrostatic attraction. The developed in situ magnetic separation technology provides a great potential for saving time and energy associated with improving microalgal harvesting. PMID:21890346

  16. Effect of gamma-ray radiation on the separation efficiencies of coated magnetic microparticles

    International Nuclear Information System (INIS)

    Volume reduction of high-level waste in the Hanford tanks is both a financial and waste reduction priority. Removal of transuranic (TRU) elements, 137Cs, and 9OSr from supernatant dissolved salts and sludge is being investigated. The removal is to be done with specially coated magnetic microparticles. Magnetic particles are used because they are relatively easy to harvest, and a wide variety of coatings can be obtained. If successful, this separation process, which uses simple, compact, and low-maintenance apparatus (compared to conventional ion exchange and solvent extraction techniques), can significantly reduce the volume of waste requiring vitrification. After TRU, 137Cs, and 9OSr removal, the remaining waste is to be converted to grout, a form of cement. The initial waste focus of the study is the development of different coatings on the magnetic particles that are selective for TRU and 137Cs. The ultimate attractiveness of this separation method depends on the ability to reuse particles 10 to 100 times after the cesium or TRU has been recovered from them. The susceptibility of the outer coatings and the magnetic cores of the particles to radiation and the subsequent effect on separation efficiency will determine how often the particles can be recycled

  17. Development and creation of the electromagnetic separator for isotope separation in the system of opposing axisymmetric magnetic fields with two fields reversed

    International Nuclear Information System (INIS)

    The paper reports the results of work on creation of a setup for isotope separation in the system of opposing axisymmetric magnetic fields with two field reverses. Consideration is given to a real possibility of improving the efficiency of the electromagnetic separator and its resolving power in the double-reverse magnetic field system. It is demonstrated that the use of the opposing axisymmetric field system may substantially reduce the energy consumption during the process of isotope separation. The estimated magnetic field of the facility attests to a possibility of molybdenum isotope separation and isolation of high-purity 98Mo and 100Mo isotopes required for production of the 99Mo/99Tc generator, most widely used in modern medicine.

  18. On-chip micro-electromagnets for magnetic-based bio-molecules separation

    International Nuclear Information System (INIS)

    This paper reports a comprehensive theoretical, finite element and measurement analysis of different designs of planar micro-electromagnets for bio-molecular manipulation. The magnetic field due to current flowing in complex shapes of current-carrying conductors have been calculated analytically, simulated using finite-element analysis (FEA), and measured using the superconducting quantum interference device technique (SQUID). A comparison of the theoretical and measured magnetic field strength and patterns is presented. The planar electromagnets have been fabricated using patterned Al 2 ?m thick. The aim of the study is to explore and optimize the geometrical and structural parameters of planar electromagnets that give rise to the highest magnetic fields and forces for magnetic micro-beads manipulation. Magnetic beads are often used in biochemical assays for separation of bio-molecules. Typical beads are 0.2-10 ?m in diameter and have superparamagnetic properties. Increasing the intensity of the magnetic field generated by a coil by injection a larger current is not the most suitable solution as the maximum current is limited by Joule heating. Consequently, in order to maximize the field for a given current, one should optimize the geometry of the coil, as this is an extremely significant factor in determining the magnetic field intensity in 2D planar designs. The theoretical and measured results of this work show that the meander micro-electromagnet with mesh-shapander micro-electromagnet with mesh-shaped winding profile produces the strongest magnetic field (about 2.7 ?T for a current intensity of 6 mA) compared with other meander designs, such as the serpentine and rosette-shaped ones. The magnetic fields of these three types of meander-shaped micro-electromagnets were compared theoretically with that produced by a spiral micro-electromagnet whose technological realization is more complicated and costly due to the fact that it requires an additional insulation layer with a contact window and a second patterned metal layer as a via. Nevertheless, the spiral design produces a much stronger magnetic field up to five times larger than that of the mesh-shaped micro-electromagnet for the same current and electromagnet area. The measured results strongly agree with these conclusions resulted from the theoretical analysis. The results presented in this paper provide a solid and useful basis for the design of a micro-fluidic bio-molecule separation and detection system using magnetic fields and magnetic beads

  19. Removal of malaria-infected red blood cells using magnetic cell separators: A computational study

    Science.gov (United States)

    Kim, Jeongho; Massoudi, Mehrdad; Antaki, James F.; Gandini, Alberto

    2012-01-01

    High gradient magnetic field separators have been widely used in a variety of biological applications. Recently, the use of magnetic separators to remove malaria-infected red blood cells (pRBCs) from blood circulation in patients with severe malaria has been proposed in a dialysis-like treatment. The capture efficiency of this process depends on many interrelated design variables and constraints such as magnetic pole array pitch, chamber height, and flow rate. In this paper, we model the malaria-infected RBCs (pRBCs) as paramagnetic particles suspended in a Newtonian fluid. Trajectories of the infected cells are numerically calculated inside a micro-channel exposed to a periodic magnetic field gradient. First-order stiff ordinary differential equations (ODEs) governing the trajectory of particles under periodic magnetic fields due to an array of wires are solved numerically using the 1st –5th order adaptive step Runge-Kutta solver. The numerical experiments show that in order to achieve a capture efficiency of 99% for the pRBCs it is required to have a longer length than 80 mm; this implies that in principle, using optimization techniques the length could be adjusted, i.e., shortened to achieve 99% capture efficiency of the pRBCs. PMID:22345827

  20. High-gradient magnetic separation for the treatment of high-level radioactive wastes

    International Nuclear Information System (INIS)

    Argonne National Laboratory is developing an open-gradient magnetic separation (OGMS) system to fractionate and remove nonglass-forming species from high-level radioactive wastes (HLW); however, to avoid clogging, OGMS may require high-gradient magnetic separation (HGMS) as a pretreatment to remove the most magnetic species from the HLW. In this study, the feasibility of using HGMS in the pretreatment of HLW was demonstrated. A HLW simulant of hanford's C-103 tank waste, which contained precipitate hydroxides and oxides of Fe, Al, Si, and Ca, was used. Preliminary fractionation results from a 0.3-T bench-scale HGMS unit showed that a significant amount of Fe could be removed from the HLW simulant. Between 1 and 2% of the total Fe in the sludge was removed during each stage, with over 18.5% removed in the 13 stages that were carried out. Also, in each stage, the magnetically retained fraction contained about 20% more Fe than the untreated HLW; however, it also contained a significant amount of SiO2 in relatively large particles. This indicated that SiO2 was acting possibly as a nucleation agent for Fe (i.e., an Fe adsorbent) and that the fractionation was based more on size than on magnetic susceptibility

  1. Characterization of steel grit recovered from ornamental rocks waste by magnetic separation; Caracterizacao da granalha de aco recuperada do residuo de rochas ornamentais por separacao magnetica

    Energy Technology Data Exchange (ETDEWEB)

    Junca, E.; Telles, V.B.; Rodrigues, G.F.; Oliveira, J.R. de; Tenorio, J.A.S., E-mail: eduardojunca@gmail.co [Universidade de Sao Paulo (USP), SP (Brazil). Dept. de Engenharia Metalurgica e de Materiais; Instituto Federal de Ciencia e Tecnologia do Espirito Santo (IFES), Vitoria, ES (Brazil)

    2010-07-01

    The aim of this work is characterization of steel grit recovered from ornamental rock waste by magnetic separation. The magnetic separation was realized in three steps: first, using a high intensity wet magnetic separator, which used only the remaining magnetic field of equipment. In the second step, the magnetic material obtained in the first phase was subjected to a new manual magnetic separation using rare earth magnets. In a third step, magnetic material obtained with rare earth magnets was subjected to manual magnetic separation using ferrite magnets. After the magnetic separation, the material was sent to characterization which was obtained by chemical analysis, scanning electron microscopy, X-ray diffraction and size analysis. The size analysis showed that the concentrate range from 0,5 to 563,67 {mu}m with 4 wt.% over 100 {mu}m and content metallic iron of 93 wt%. (author)

  2. Purification of a primary coolant in a nuclear power plant using a magnetic filter - electrodeionization hybrid separation system

    International Nuclear Information System (INIS)

    A magnetic filter - continuous electrodeionization (CEDI) hybrid separation system was investigated for the purification of the primary coolant in a nuclear power plant. A magnetic filter system with a 3000 Gauss magnetic field and a CEDI system with a cell consisting of 3 compartments were used for the removal of magnetite and nickel ions, respectively. The hybrid separation system achieved removal rates of 98% for magnetite and 99% for the nickel ions demonstrating its feasibility for the purification of primary coolant. (author)

  3. Spectral functions in a magnetic field as a probe of spin-charge separation in a Luttinger liquid

    OpenAIRE

    Rabello, Silvio; Si, Qimiao

    2000-01-01

    We show that the single-particle spectral functions in a magnetic field can be used to probe spin-charge separation of a Luttinger liquid. Away from the Fermi momentum, the magnetic field splits both the spinon peak and holon peak; here the spin-charge separation nature is reflected in the different magnitude of the two splittings. At the Fermi momentum, the magnetic field splits the zero-field peak into {\\it four} peaks. The feasibility of experimentally studying this effec...

  4. Fermi Surface Reconstruction by Dynamic Magnetic Fluctuations and Spin-Charge Separation Near an O(3) Quantum Critical Point

    OpenAIRE

    Holt, Michael; Oitmaa, Jaan; Chen, Wei; Sushkov, Oleg P.

    2012-01-01

    Stimulated by the small/large Fermi surface controversy in the cuprates we consider a small number of holes injected into the bilayer antiferromagnet. The system has an O(3) quantum critical point (QCP) separating the magnetically ordered and the magnetically disordered phases. We demonstrate that nearly critical quantum magnetic fluctuations can change the Fermi surface topology and also lead to spin charge separation (SCS) in two dimensions. We demonstrate that in the phys...

  5. ''Ionic'' isotope-separation mechanisms in an rf system with a traveling magnetic field

    International Nuclear Information System (INIS)

    Possible mechanisms for the separation of isotopic mixtures in gas-discharge systems with a traveling magnetic field are studied for moderate pressures. A multicomponent hydrodynamic approximation and certain assumptions regarding the ambipolar diffusion of the charged particles are used to study the separation mechanisms which result from two factors: a difference between the longitudinal forces associated with the diffusive friction of ions with neutrals of both species and a difference between the degrees of ionization of the isotopes in the case of an ''active'' plasma

  6. Haloing in bimodal magnetic colloids: the role of field-induced phase separation.

    Science.gov (United States)

    Magnet, C; Kuzhir, P; Bossis, G; Meunier, A; Suloeva, L; Zubarev, A

    2012-07-01

    If a suspension of magnetic micrometer-sized and nanosized particles is subjected to a homogeneous magnetic field, the nanoparticles are attracted to the microparticles and form thick anisotropic halos (clouds) around them. Such clouds can hinder the approach of microparticles and result in effective repulsion between them [M. T. López-López, A. Yu. Zubarev, and G. Bossis, Soft Matter 6, 4346 (2010)]. In this paper, we present detailed experimental and theoretical studies of nanoparticle concentration profiles and of the equilibrium shapes of nanoparticle clouds around a single magnetized microsphere, taking into account interactions between nanoparticles. We show that at a strong enough magnetic field, the ensemble of nanoparticles experiences a gas-liquid phase transition such that a dense liquid phase is condensed around the magnetic poles of a microsphere while a dilute gas phase occupies the rest of the suspension volume. Nanoparticle accumulation around a microsphere is governed by two dimensionless parameters--the initial nanoparticle concentration (?(0)) and the magnetic-to-thermal energy ratio (?)--and the three accumulation regimes are mapped onto a ?-?(0) phase diagram. Our local thermodynamic equilibrium approach gives a semiquantitative agreement with the experiments on the equilibrium shapes of nanoparticle clouds. The results of this work could be useful for the development of the bimodal magnetorheological fluids and of the magnetic separation technologies used in bioanalysis and water purification systems. PMID:23005414

  7. Measurement of the magnetic interaction between two bound electrons of two separate ions

    Science.gov (United States)

    Kotler, Shlomi; Akerman, Nitzan; Navon, Nir; Glickman, Yinnon; Ozeri, Roee

    2014-06-01

    Electrons have an intrinsic, indivisible, magnetic dipole aligned with their internal angular momentum (spin). The magnetic interaction between two electronic spins can therefore impose a change in their orientation. Similar dipolar magnetic interactions exist between other spin systems and have been studied experimentally. Examples include the interaction between an electron and its nucleus and the interaction between several multi-electron spin complexes. The challenge in observing such interactions for two electrons is twofold. First, at the atomic scale, where the coupling is relatively large, it is often dominated by the much larger Coulomb exchange counterpart. Second, on scales that are substantially larger than the atomic, the magnetic coupling is very weak and can be well below the ambient magnetic noise. Here we report the measurement of the magnetic interaction between the two ground-state spin-1/2 valence electrons of two 88Sr+ ions, co-trapped in an electric Paul trap. We varied the ion separation, d, between 2.18 and 2.76 micrometres and measured the electrons' weak, millihertz-scale, magnetic interaction as a function of distance, in the presence of magnetic noise that was six orders of magnitude larger than the magnetic fields the electrons apply on each other. The cooperative spin dynamics was kept coherent for 15 seconds, during which spin entanglement was generated, as verified by a negative measured value of -0.16 for the swap entanglement witness. The sensitivity necessary for this measurement was provided by restricting the spin evolution to a decoherence-free subspace that is immune to collective magnetic field noise. Our measurements show a d-3.0(4) distance dependence for the coupling, consistent with the inverse-cube law.

  8. Review and evaluation of extractants for strontium removal using magnetically assisted chemical separation

    International Nuclear Information System (INIS)

    A literature review on extractants for strontium removal was initially performed at Northern Illinois University to assess their potential in magnetically assisted chemical separation. A series of potential strontium extractants was systematically evaluated there using radioanalytical methods. Initial experiments were designed to test the uptake of strontium from nitric acid using several samples of magnetic extractant particles that were coated with various crown ether ligands. High partition coefficient (Kd) values for stimulant tank waste were obtained. Further studies demonstrated that the large partitioning was due to uncoated particles

  9. Beta-NMR magnetic moment measurement using on-line mass separation and tilted foil polarization

    International Nuclear Information System (INIS)

    Tilted foil polarization and on-line mass separation have been successfully applied to a ?-NMR technique for measuring nuclear moments. Nuclei are polarized using tilted carbon foils (multifoil array) and implanted in a catcher. Nuclear polarization, monitored by detection of anisotropic ?-emission, is destroyed via resonant rf excitation to locate the NMR. Tests were performed using 12B (T1/2 = 20.4 ms, I? = 1+) and the ground-state magnetic moment of 33Cl (T1/2 = 2.51 s, I? = 3/2+) was measured using this arrangement. The 33Cl magnetic moment, corrected for diamagnetism, is ? = +0.7523(16) nm. (orig.)

  10. The separation of diffuse nuclear and magnetic neutron scattering from antiferromagnetic MnCu alloys by polarization analysis

    International Nuclear Information System (INIS)

    Neutron polarization analysis has been used to separate the nuclear and magnetic scattering from ?-MnCu alloys. The diffuse peak centred around the /100/ position is shown to be almost completely magnetic in origin and to be associated with the (001) reciprocal lattice point. Possible mechanisms that may explain the occurrence of this diffuse magnetic peak are discussed. (author)

  11. A continuous, hybrid field-gradient device for magnetic colloid-based separations

    International Nuclear Information System (INIS)

    A fully continuous, hybrid field-gradient device is developed for colloidal magnetic affinity separation. The device consists of a 1.0 cm internal diameter 1.2 m long, axially rotating horizontal glass chamber, with four repeating magnetic units distributed axially along the tube. Each magnetic unit consists of a stationary alternating-current solenoid that surrounds the chamber, followed by a direct current flowing, computer-controlled electromagnet, placed at a distance of 4.0 cm from the end of the solenoid. The alternating-current-carrying solenoids impart translational and rotary oscillations to the magnetic particles, enhancing mixing. The computer-controlled electromagnets draw the magnetic particles to the chamber walls, and increase their residence time in the chamber. By manipulating the on-off cycle for these electromagnets, the exiting solution can be switched between one that contains a negligible concentration of target-bound magnetic particles and one that has a high concentration of the target, without interrupting the feed. The operation of this device is demonstrated for the removal of cadmium ions from a cadmium sulfate solution. 1-10 ?m diameter anion-exchange-resin-coated magnetic particles at a concentration of 0.5 mg particles/ml were used as the mobile solid support. The feed consisted of a 10.0 mg/l cadmium sulfate solution, at a flow rate of 25 ml/min. The device was operated as a three-stage cross-current cascade. For this system, 45%, 58% rrent cascade. For this system, 45%, 58% and 63% of the entering cadmium ions are removed at each stage, respectively, with stage efficiencies that vary between 57% and 65%. Thus, more than 90% of the entering cadmium ions are removed. While this device has been demonstrated for metal ion removal from an aqueous feed, it can potentially be applied to several other affinity-based separations

  12. A magnetic electron separator for beta spectroscopy with a Ge(HP)-detector

    International Nuclear Information System (INIS)

    A beta spectrometer consisting of an angle- and energy-focusing magnetic sector field and a Ge(HP)-detector has been constructed for the measurement of beta endpoint energies and for ?-?-angular correlation studies. The system has an effective acceptance solid angle of 0.4% of 4? and an energy transmission of approximately +- 5% around a chosen mean energy. First measurements were performed on the on-line mass separator OSTIS at the ILL. The cutoff of low energy electrons enabled rapid data accumulation since the full intensity of the mass separator could be used and pile-up problems were avoided. Better ?-shielding, because of magnetic focusing of the beta particles, significantly reduced the background in the beta spectra relative to previous measurements at OSTIS. The apparatus has also been used to refine the response function of our Ge(HP)-detector. (orig.)

  13. Ceramic Tl-oxide based superconductors reinvestigated by magnetic separation technique and SQUID measurements

    Science.gov (United States)

    Mogare, K. M.; Landau, I.; Guérin, N.; Trusch, B.; Wagner, M.; Locherer, T.; Jansen, M.; Hulliger, J.

    2011-10-01

    Ceramic samples of Tl 2Ba 2Ca 2Cu 3O 10 (Tl-2223) and TlBa 2Ca 2Cu 3O 9 (Tl-1223) superconductor were resynthesized by using several preparation procedures and investigated by means of magnetic separation technique, allowing evaluation of the superconducting critical temperature of individual grains as small as 25 ?m. Although an onset of diamagnetism detected by SQUID measurements was observed around 130 K in Tl-2223 and 134 K in Tl-1223, no grains with T c > 125 K were found for Tl-2223 and with T c > 130 K for Tl-1223. Furthermore, the volume fraction of superconductivity of such ceramics was less than 5% and 3% in best samples of Tl-2223 and Tl-1223, respectively. Here we provide a detailed comparison of results obtained by magnetic separation technique with those by SQUID applied to individual grains and bulk samples.

  14. Spin-Charge Separation in Two-dimensional Frustrated Quantum Magnets

    OpenAIRE

    Laeuchli, A.; Poilblanc, D.

    2003-01-01

    The dynamics of a mobile hole in two-dimensional frustrated quantum magnets is investigated by exact diagonalization techniques. Our results provide evidence for spin-charge separation upon doping the kagome lattice, a prototype of a spin liquid. In contrast, in the checkerboard lattice, a symmetry broken Valence Bond Crystal, a small quasi-particle peak is seen for some crystal momenta, a finding interpreted as a restoration of weak holon-spinon confinement.

  15. Fluorescent and superparamagnetic hybrid quantum clusters for magnetic separation and imaging of cancer cells from blood

    Science.gov (United States)

    Durgadas, C. V.; Sharma, Chandra P.; Sreenivasan, K.

    2011-11-01

    We demonstrate here the generation of fluorescent superparamagnetic quantum clusters through a greener aqueous route by fusing highly fluorescent gold clusters with superparamagnetic nanoparticles. We conjugated transferrin onto the hybrid clusters to get cell accessibility and assessed their hemocompatibility and cytotoxicity. The ability of the clusters to selectively remove cancer cell lines (C6 glioma cells) from fluids including blood and the fluorescent imaging of the separated cells is demonstrated. The pattering of the clusters in response to an external magnetic field is also shown. Efficient cancer cell separation, imaging and magnetic pattering can be realized by the highly hemocompatible and noncytotoxic hybrid clusters reported here. It seems the probe has potential for further exploration in multimodal imaging of circulating cancer cells.We demonstrate here the generation of fluorescent superparamagnetic quantum clusters through a greener aqueous route by fusing highly fluorescent gold clusters with superparamagnetic nanoparticles. We conjugated transferrin onto the hybrid clusters to get cell accessibility and assessed their hemocompatibility and cytotoxicity. The ability of the clusters to selectively remove cancer cell lines (C6 glioma cells) from fluids including blood and the fluorescent imaging of the separated cells is demonstrated. The pattering of the clusters in response to an external magnetic field is also shown. Efficient cancer cell separation, imaging and magnetic pattering can be realized by the highly hemocompatible and noncytotoxic hybrid clusters reported here. It seems the probe has potential for further exploration in multimodal imaging of circulating cancer cells. Electronic supplementary information (ESI) available: HRTEM, FTIR spectra, XRD of the samples and fluorescent microscope images are showed in supporting information in the order they discussed in the text. See DOI: 10.1039/c1nr10900f

  16. Antibody conjugated magnetic iron oxide nanoparticles for cancer cell separation in fresh whole blood.

    Science.gov (United States)

    Xu, Hengyi; Aguilar, Zoraida P; Yang, Lily; Kuang, Min; Duan, Hongwei; Xiong, Yonghua; Wei, Hua; Wang, Andrew

    2011-12-01

    A highly efficient process using iron oxide magnetic nanoparticles (IO)-based immunomagnetic separation of tumor cells from fresh whole blood has been developed. The process involved polymer coated 30 nm IO that was modified with antibodies (Ab) against human epithelial growth factor receptor 2 (anti-HER2 or anti-HER2/neu) forming IO-Ab. HER2 is a cell membrane protein that is overexpressed in several types of human cancer cells. Using a HER2/neu overexpressing human breast cancer cell line, SK-BR3, as a model cell, the IO-Ab was used to separate 73.6% (with a maximum capture of 84%) of SK-BR3 cells that were spiked in 1 mL of fresh human whole blood. The IO-Ab preferentially bound to SK-BR3 cells over normal cells found in blood due to the high level of HER2/neu receptor on the cancer cells unlike the normal cell surfaces. The results showed that the nanosized magnetic nanoparticles exhibited an enrichment factor (cancer cells over normal cells) of 1:10,000,000 in a magnetic field (with gradient of 100 T/m) through the binding of IO-Ab on the cell surface that resulted in the preferential capture of the cancer cells. This research holds promise for efficient separation of circulating cancer cells in fresh whole blood. PMID:21920599

  17. Selective separation of lambdacyhalothrin by porous/magnetic molecularly imprinted polymers prepared by Pickering emulsion polymerization.

    Science.gov (United States)

    Hang, Hui; Li, Chunxiang; Pan, Jianming; Li, Linzi; Dai, Jiangdong; Dai, Xiaohui; Yu, Ping; Feng, Yonghai

    2013-10-01

    Porous/magnetic molecularly imprinted polymers (PM-MIPs) were prepared by Pickering emulsion polymerization. The reaction was carried out in an oil/water emulsion using magnetic halloysite nanotubes as the stabilizer instead of a toxic surfactant. In the oil phase, the imprinting process was conducted by radical polymerization of functional and cross-linked monomers, and porogen chloroform generated steam under the high reaction temperature, which resulted in some pores decorated with easily accessible molecular binding sites within the as-made PM-MIPs. The characterization demonstrated that the PM-MIPs were porous and magnetic inorganic-polymer composite microparticles with magnetic sensitivity (M(s) = 0.7448 emu/g), thermal stability (below 473 K) and magnetic stability (over the pH range of 2.0-8.0). The PM-MIPs were used as a sorbent for the selective binding of lambdacyhalothrin (LC) and rapidly separated under an external magnetic field. The Freundlich isotherm model gave a good fit to the experimental data. The adsorption kinetics of the PM-MIPs was well described by pseudo-second-order kinetics, indicating that the chemical process could be the rate-limiting step in the adsorption of LC. The selective recognition experiments exhibited the outstanding selective adsorption effect of the PM-MIPs for target LC. Moreover, the PM-MIPs regeneration without significant loss in adsorption capacity was demonstrated by at least four repeated cycles. PMID:23894024

  18. The gas-filled magnet: An isobar separator for accelerator mass spectrometry

    International Nuclear Information System (INIS)

    The most difficult problem for accelerator mass spectrometry is the rejection of stable atomic isobars. The intensity of isobaric interference is expected to become a problem for 36Cl measurements with the use of new high-intensity ion sources. Although better chemical separation may be possible through improved sample preparation, the device expected to help most with this problem is the gas-filled magnet. We tested a gas-filled Enge split-pole spectrograph combined with a multi-plate gas ionization detector for the separation of 36S from 36Cl and obtained an isobar separation of about two orders of magnitude better than that possible with the detector alone. 10 refs., 3 figs., 1 tab

  19. Controlled synthesis of Fe3O4/ZIF-8 nanoparticles for magnetically separable nanocatalysts.

    Science.gov (United States)

    Pang, Fei; He, Mingyuan; Ge, Jianping

    2015-04-27

    Fe3O4/ZIF-8 nanoparticles were synthesized through a room-temperature reaction between 2-methylimidazolate and zinc nitrate in the presence of Fe3O4 nanocrystals. The particle size, surface charge, and magnetic loading can be conveniently controlled by the dosage of Zn(NO3)2 and Fe3O4 nanocrystals. The as-prepared particles show both good thermal stability (stable to 550?°C) and large surface area (1174?m(2) g(-1)). The nanoparticles also have a superparamagnetic response, so that they can strongly respond to an external field during magnetic separation and disperse back into the solution after withdrawal of the magnetic field. For the Knoevenagel reaction, which is catalyzed by alkaline active sites on external surface of catalyst, small Fe3O4/ZIF-8 nanoparticles show a higher catalytic activity. At the same time, the nanocatalysts can be continuously used in multiple catalytic reactions through magnetic separation, activation, and redispersion with little loss of activity. PMID:25766136

  20. Study of excess Fe metal in the lunar fines by magnetic separation, Moessbauer spectroscopy, and microscopic examination.

    Science.gov (United States)

    Housley, R. M.; Grant, R. W.; Abdel-Gawad, M.

    1972-01-01

    A simple and convenient method of making quantitative magnetic separations has been applied to the lunar fines. The fractions obtained form groups containing distinctively different particle types; thus, it appears that magnetic separation in itself many be a useful way of characterizing lunar fines. Moessbauer studies of fines 10084 show that the metal cannot contain more than about 1.5% Ni, implying that by far the bulk of the metal results from reduction rather than from direct meteoritic addition. Microscopic examination of magnetic separates from 15101 fines suggests that reduction of Fe accompanies every major impact event on the moon.

  1. Reduction of the magnetic signal from unbound magnetic markers for magnetic immunoassay without bound/free separation

    Energy Technology Data Exchange (ETDEWEB)

    Tsukamoto, A. [Advanced Research Laboratory, Hitachi, Ltd., Kokubunji-shi, Tokyo 185-8601 (Japan)], E-mail: akira.tsukamoto.tw@hitachi.com; Kuma, H. [Faculty of Pharmaceutical Sciences, Nagasaki International University, 2825-7 Huis Ten Bosch-cho, Sasebo-shi, Nagasaki 859-3298 (Japan); Saitoh, K.; Kandori, A. [Advanced Research Laboratory, Hitachi, Ltd., Kokubunji-shi, Tokyo 185-8601 (Japan); Yoshinaga, K. [Department of Applied Chemistry, Kyushu Institute of Technology, Tobata-ku, Kitakyushu-shi, Fukuoka 804-8550 (Japan); Sugiura, Y. [Plastic products division, INOAC Corporation, Atsuta-ku, Nagoya-shi, Aichi 456-0054 (Japan); Hamasaki, N. [Faculty of Pharmaceutical Sciences, Nagasaki International University, 2825-7 Huis Ten Bosch-cho, Sasebo-shi, Nagasaki 859-3298 (Japan); Enpuku, K. [Research Institute of Superconductor Science and Systems, Kyushu University, Hakozaki, Higashi-ku, Fukuoka-shi, Fukuoka 812-8581 (Japan)

    2007-10-01

    We investigated the effect of adding magnetic shielding and applying of a compensation field to reduce the magnetic signal from unbound free markers. When the initial immunoassay system was used without the additional shielding box, the signal intensity of the liquid markers normalized by the weight of the Fe{sub 3}O{sub 4} was 1/2700 of the dried markers. By installing the additional shielding box, the reduction factor was improved to 1/10,000. We successfully reduced the magnetic signal of the liquid marker further by applying a compensation field. The magnetic signal of the free marker obtained by applying a compensation field of -18 nT was 1.4 m{phi}{sub 0}, which was close to the system noise level. Field compensation at the very local area just around the SQUID is sufficient for reducing of the magnetic signal from the free marker.

  2. Lipid-Based Immuno-Magnetic Separation of Archaea from a Mixed Community

    Science.gov (United States)

    Frickle, C. M.; Bailey, J.; Lloyd, K. G.; Shumaker, A.; Flood, B.

    2014-12-01

    Despite advancing techniques in microbiology, an estimated 98% of all microbial species on Earth have yet to be isolated in pure culture. Natural samples, once transferred to the lab, are commonly overgrown by "weed" species whose metabolic advantages enable them to monopolize available resources. Developing new methods for the isolation of thus-far uncultivable microorganisms would allow us to better understand their ecology, physiology and genetic potential. Physically separating target organisms from a mixed community is one approach that may allow enrichment and growth of the desired strain. Here we report on a novel method that uses known physiological variations between taxa, in this case membrane lipids, to segregate the desired organisms while keeping them alive and viable for reproduction. Magnetic antibodies bound to the molecule squalene, which is found in the cell membranes of certain archaea, but not bacteria, enable separation of archaea from bacteria in mixed samples. Viability of cells was tested by growing the separated fractions in batch culture. Efficacy and optimization of the antibody separation technique are being evaluated using qPCR and cell counts. Future work will apply this new separation technique to natural samples.

  3. Removal and recycle of phosphate from treated water of sewage plants with zirconium ferrite adsorbent by high gradient magnetic separation

    International Nuclear Information System (INIS)

    Zirconium ferrite particles are good adsorbent for phosphate ions. Magnetic separation characteristics for removal of phosphate from treated water of sewage plants with the adsorbent have been studied to prevent eutrophication of semi-enclosed bay, e.g. the bay of Tokyo. Based on the adsorption for the phosphate ions and ferromagnetic properties of the zirconium ferrite adsorbent, high gradient magnetic separation characteristics with using superconducting magnet was discussed. Very rapid magnetic filtration velocity, i.e. 1m/s, and regeneration properties of the adsorbent indicate that the zirconium ferrite is the excellent adsorbent for phosphorus removal and recycle from treated water of large scale sewage plants.

  4. Separator current sheets: Generic features in minimum-energy magnetic fields subject to flux constraints

    International Nuclear Information System (INIS)

    Equations are found for force-free magnetic equilibria in the 'coronal half-space' z>0, subject to boundary conditions on the normal magnetic field at z=0. The distribution of normal field is assumed to be composed of NS isolated unipolar source regions of arbitrary shape, arranged arbitrarily on the plane. The equilibria are found by minimizing the magnetic energy subject to constraints on the total flux interconnecting pairs of source regions. For NS source regions interconnected in ND ways, there are Nc=ND-NS+1 distinct constraints on the field. Minimization subject to these constraints leads to an Nc-dimensional space of equilibria, for given boundary data. All field-lines connecting source regions are current-free, but the equilibrium contains Nc current-sheets lying at certain interfaces. In a two-dimensional magnetic field current sheets occur at points topologically equivalent to X-type neutral points in the potential field. In a three-dimensional field current sheets occur at points topologically equivalent to separators in the potential field. The free magnetic energy is a function of the Nc fluxes used to constrain the variation

  5. Magnetic particle separation technique: a reliable and simple tool for RIA/IRMA and quantitative PCR assay

    International Nuclear Information System (INIS)

    Five types of magnetic particles without or with aldehyde, amino and carboxyl functional groups, respectively were used to immobilize first or second antibody by three models, i. e. physical adsorption, chemical coupling and immuno-affinity, forming four types of magnetic particle antibodies. The second antibody immobilized on polyacrolein magnetic particles through aldehyde functional groups and the first antibodies immobilized on carboxylic polystyrene magnetic particles through carboxyl functional groups were recommended to apply to RIAs and/or IRMAs. Streptavidin immobilized on commercial magnetic particles through amino functional groups was successfully applied to separating specific PCR product for quantification of human cytomegalovirus. In the paper typical data on reliability of these magnetic particle ligands were reported and simplicity of the magnetic particle separation technique was discussed. The results showed that the technique was a reliable and simple tool for RIA/IRMA and quantitative PCR assay. (author)

  6. Accessible and green manufacturing of magnetite (ferrous ferric oxide) nanocrystals and their use in magnetic separations

    Science.gov (United States)

    Yavuz, Cafer Tayyar

    This work describes the first size dependent magnetic separation in nanoscale. Magnetite (Fe3O4) nanocrystals of high quality and uniform size were synthesized with monodispersity below 10%. Magnetite nanocrystals of 4 nm to 33 nm (average diameter) were produced. Batch synthesis was shown to go up to 20 grams which is more than 10 times of a standard nanocrystal synthesis, without loosing the quality and monodispersity. Reactor design for mass (1 gram per hour) production of magnetite nanocrystals is reported for the first time. The cost of a kg of lab purity magnetite nanocrystals was shown to be 2600. A green synthesis that utilizes rust and edible oils was developed. The cost of a kg was brought down to 22. Size dependency of magnetism was shown in nanoscale for the first time. Reversible aggregation theory was developed to explain the low field magnetic separation and solution behavior of magnetite nanocrystals. Arsenic was removed from drinking water with magnetite nanocrystals 200 times better than commercial adsorbents. Silica coating was successfully applied to enable the known silica related biotechnologies. Magnetite-silica nanoshells were functionalized with amino groups. For the first time, silver was coated on the magnetite-silica nanoshells to produce triple multishells. Anti-microbial activity of multishells is anticipated.

  7. Separation in a nonuniform magnetic field of the isotopes of atoms interacting with an intense resonant light wave

    International Nuclear Information System (INIS)

    The process of optical orientation of atomic isotopes in the field of a strong resonant light wave and an inhomogeneous magnetic field is analyzed and the conditions for reliable isotope separation are determined

  8. Three-dimensional modeling of a portable medical device for magnetic separation of particles from biological fluids

    International Nuclear Information System (INIS)

    A portable separator has been developed to quantitatively separate blood-borne magnetic spheres in potentially high-flow regimes for the human detoxification purpose. In the separator design, an array of biocompatible capillary tubing and magnetizable wires is immersed in an external magnetic field that is generated by two permanent magnets. The wires are magnetized and the high magnetic field gradient from the magnetized wires helps to collect blood-borne magnetic nano/micro-spheres from the blood flow. In this study, a 3D numerical model was created and the effect of tubing-wire configurations on the capture efficiency of the system was analyzed using COMSOL Multiphysics 3.3 (registered) . The results showed that the configuration characterized by bi-directionally alternating wires and tubes was the best design with respect to the four starting configurations. Preliminary in vitro experiments verified the numerical predictions. The results helped us to optimize a prototype portable magnetic separator that is suitable for rapid sequestration of magnetic nano/micro-spheres from the human blood stream while accommodating necessary clinical boundary conditions

  9. Structural studies, magnetic properties and loss separation in iron-phenolicsilane soft magnetic composites

    International Nuclear Information System (INIS)

    In this work, six different series of iron based soft magnetic composites are produced and studied: (1) passive iron powder; (2) passive iron powder-0.7% resin with coupling agent; (3) passive iron powder-0.7% resin without coupling agent; (4) passive iron powder-1.5% resin with coupling agent; (5) passive iron powder-1.5% resin without coupling agent; (6) pure iron-1.5% resin. The specimens were shaped as cylindrical rods and characterized by fourier transform infrared spectrometer (FTIR), energy dispersive analyzer (EDX), X-ray diffraction (XRD) and indutance capacitance resistance (LCR) meter. The results show that the hysteresis loss coefficient is close to each other for all the samples (0.0011 2 3 = 0.005) in comparison with the other samples.

  10. Synthesis of new type of Au-magnetic nanocomposite and application for protein separation thereof

    Science.gov (United States)

    Song, Yu; Tao, Ling; Shen, Xiangchun

    2012-07-01

    We present a different strategy for synthesizing the Au-?-Fe2O3 bifunctional nanoparticle by using a larger (50 nm) Au nanoparticle as the core surrounded by smaller (10 nm) ?-Fe2O3 nanoparticles. The synthesis of the composite nanoparticles is quite facile based on a simple redox process whereby Fe2+ is used to reduce Au3+. The morphology and composition of the product is measured by transmission electron microscopy, X-ray powder diffraction and UV-vis spectroscopy. We demonstrate the utility of these as-prepared Au-?-Fe2O3 nanoparticles by showing they can be used to separate proteins in solution. For example, bovine serum is efficiently removed from an aqueous solution with the simple addition of the NPs and application of a small magnet. Sodium dodecyl sulfate-polyacrylamide gel electrophoresis is performed to evaluate the fidelity and efficiency of the protein separation procedure.

  11. Eddy current and total power loss separation in the iron-phosphate-polyepoxy soft magnetic composites

    International Nuclear Information System (INIS)

    This work investigates the magnetic properties of iron-phosphate-polyepoxy soft magnetic composite materials. FTIR spectra, EDX analysis, distribution maps, X-ray diffraction pattern and density measurements show that the particles surface layer contains a thin layer of nanocrystalline/amorphous phosphate with high coverage of powders surface. In this paper, a formula for calculating the eddy current loss and total loss components by loss separation method is presented and finally the different parts of power losses are calculated. The results show that, the contribution of eddy current in the bulk material for single coating layer (kb = 0.18) is higher in comparison with double coating layer (kb = 0.09). Moreover, iron-phosphate-polyepoxy composites (P = 0.000004f2) have lower power loss in comparison with iron-phosphate composites (P = 0.00002f2).

  12. Separation of Selenite from Inorganic Selenium Ions using TiO2 Magnetic Nanoparticles

    International Nuclear Information System (INIS)

    A simple and quick separation technique for selenite in natural water was developed using TiO2 SiO2/Fe3O4 nanoparticles. For the synthesis of nanoparticles, a polymer-assisted sol-gel method using hydroxypropyl cellulose (HPC) was developed to control particle dispersion in the synthetic procedure. In addition, titanium butoxide (TBT) precursor, instead of the typical titanium tetra isopropoxide, was used for the formation of the TiO2 shell. The synthesized nanoparticles were used to separate selenite (Se4+) in the presence of Se6+ or selenium anions for the photocatalytic reduction to Se0 atom on the TiO2 shell, followed by magnetic separation using Fe3O4 nanoparticles. The reduction efficiency of the photocatalytic reaction was 81.4% at a UV power of 6W for 3 h with a dark adsorption of 17.5% to the nanoparticles, as determined by inductively coupled plasma-mass spectrometry (ICP-MS). The developed separation method can be used for the speciation and preconcentration of selenium cations in environmental and biological analysis

  13. Antibody Conjugated Magnetic Iron Oxide Nanoparticles for Cancer Cell Separation in Fresh Whole Blood

    OpenAIRE

    Xu, Hengyi; Aguilar, Zoraida P.; Yang, Lily; Kuang, Min; Duan, Hongwei; Xiong, Yonghua; Wei, Hua; Wang, Andrew

    2011-01-01

    A highly efficient process using iron oxide magnetic nanoparticles (IO)-based immunomagnetic separation of tumor cells from fresh whole blood has been developed. The process involved polymer coated 30 nm IO that was modified with antibodies (Ab) against human epithelial growth factor receptor 2 (anti-HER2 or anti-HER2/neu) forming IO-Ab. HER2 is a cell membrane protein that is over expressed in several types of human cancer cells. Using a HER2/neu over expressing human breast cancer cell line...

  14. Steelmaking slag beneficiation by magnetic separator and impacts on sinter quality

    Directory of Open Access Journals (Sweden)

    Bölükba?? Ö.S.

    2014-01-01

    Full Text Available Basic oxygen furnaces (BOF slag is the main problem at all iron and steel factories. About more than 6 million tons/year of BOF slag has been accumulated from the waste stockyards in Turkey. Dumps slags can be revaluated by a processing technology which makes it possible to obtain products that meet the requirements of sintering and blast furnace production. The slags with particle size of -10 mm were enriched by the magnetic separator resulting and increase in Fe grade from 18% to 33%. The use of BOF slag in sinter blend provided additional Mn, CaO, MgO and introduced a good solution to environmental problems.

  15. Metallic Properties of the Si(111) - 5 × 2 - Au Surface from Infrared Plasmon Polaritons and Ab Initio Theory.

    Science.gov (United States)

    Hötzel, Fabian; Seino, Kaori; Huck, Christian; Skibbe, Olaf; Bechstedt, Friedhelm; Pucci, Annemarie

    2015-06-10

    The metal-atom chains on the Si(111) - 5 × 2 - Au surface represent an exceedingly interesting system for the understanding of one-dimensional electrical interconnects. While other metal-atom chain structures on silicon suffer from metal-to-insulator transitions, Si(111) - 5 × 2 - Au stays metallic at least down to 20 K as we have proven by the anisotropic absorption from localized plasmon polaritons in the infrared. A quantitative analysis of the infrared plasmonic signal done here for the first time yields valuable band structure information in agreement with the theoretically derived data. The experimental and theoretical results are consistently explained in the framework of the atomic geometry, electronic structure, and IR spectra of the recent Kwon-Kang model. PMID:25978621

  16. Effects of filter shapes on the capture efficiency of a superconducting high-gradient magnetic separation system

    International Nuclear Information System (INIS)

    This paper reports experimental and analytical studies on the capture efficiency of a superconducting high-gradient magnetic separation (HGMS) system, employing ferromagnetic filters with various wire diameters and packing fractions. The magnetization force was inversely proportional to wire diameter because the magnetic field gradient increased with decreasing wire diameter. In addition, the capture efficiency of the HGMS system was increased with decreasing wire diameter and increasing packing fraction. The experimental results from the filtration tests via the superconducting HGMS system were in reasonably good agreement with the capture efficiency using the magnetization force obtained by magnetic field analysis. (paper)

  17. Effects of filter shapes on the capture efficiency of a superconducting high-gradient magnetic separation system

    Science.gov (United States)

    Kim, Y. G.; Song, J. B.; Yang, D. G.; Lee, J. S.; Park, Y. J.; Kang, D. H.; Lee, H. G.

    2013-08-01

    This paper reports experimental and analytical studies on the capture efficiency of a superconducting high-gradient magnetic separation (HGMS) system, employing ferromagnetic filters with various wire diameters and packing fractions. The magnetization force was inversely proportional to wire diameter because the magnetic field gradient increased with decreasing wire diameter. In addition, the capture efficiency of the HGMS system was increased with decreasing wire diameter and increasing packing fraction. The experimental results from the filtration tests via the superconducting HGMS system were in reasonably good agreement with the capture efficiency using the magnetization force obtained by magnetic field analysis.

  18. Self-Doping of Gold Chains on Silicon: A New Structural Model for Si(111)5x2-Au

    OpenAIRE

    Erwin, Steven C.

    2003-01-01

    A new structural model for the Si(111)5x2-Au reconstruction is proposed and analyzed using first-principles calculations. The basic model consists of a "double honeycomb chain" decorated by Si adatoms. The 5x1 periodicity of the honeycomb chains is doubled by the presence of a half-occupied row of Si atoms that partially rebonds the chains. Additional adatoms supply electrons that dope the parent band structure and stabilize the period doubling; the optimal doping correspond...

  19. Method and apparatus for separating gases based on electrically and magnetically enhanced monolithic carbon fiber composite sorbents

    Science.gov (United States)

    Judkins, Roddie R. (9917 Rainbow Dr., Knoxville, TN 37922); Burchell, Timothy D. (109 Greywood Pl., Oak Ridge, TN 37830)

    1999-01-01

    A method for separating gases or other fluids involves placing a magnetic field on a monolithic carbon fiber composite sorption material to more preferentially attract certain gases or other fluids to the sorption material to which a magnetic field is applied. This technique may be combined with the known "pressure swing adsorption" technique utilizing the same sorption material.

  20. TREATMENT OF COMBINED SEWER OVERFLOWS BY HIGH GRADIENT MAGNETIC SEPARATION. ON-SITE TESTING WITH MOBILE PILOT PLANT TRAILER

    Science.gov (United States)

    Seeded water treatment using a SALA high gradient magnetic separator pilot plant system was conducted on combined sewer overflows and raw sewage at SALA Magnetics in Cambridge, MA and at on-site locations in the Boston area. Special emphasis was placed on specific design and oper...

  1. Inhomogeneous magnetism in single crystalline Sr$_3$CuIrO$_{6+\\delta}$: Implications to phase-separation concepts

    OpenAIRE

    Niazi, Asad; Paulose, P. L.; Sampathkumaran, E. V.

    2002-01-01

    The single crystalline form of an insulator, Sr$_3$CuIrO$_{6+\\delta}$, is shown to exhibit unexpectedly more than one magnetic transition (at 5 and 19 K) with spin-glass-like magnetic susceptibility behaviour. On the basis of this finding, viz., inhomogeneous magnetism in a chemically homogeneous material, we propose that the idea of "phase- separation" described for manganites [1] is more widespread in different ways. The observed experimental features enable us to make a c...

  2. Magnetic isotope effect and isotope separation under photolysis of dibenzylketone; dependence on viscosity and electron-nuclear interaction

    International Nuclear Information System (INIS)

    Dependence of effectiveness of magnetic isotope redis tribution on the solvent mixture of glycerine and butanol viscosity is investigated on the example of dibenzylketone (DBK) photolysis. Changes in 13C isotope content in dibenzylketone molecules and dibenzyl molecules-DBK photolysis product are measured. It is shown that the stronger is the difference of effective electron-nuclear interactions in the magnetic and non-magnetic radical pairs the higher is the effectiveness of isotope separation. Isotope separation takes place more effectively at a certain, optimal viscosity of the solvent, in which the reaction proceeds

  3. Removal and recovery of phosphorus in wastewater by superconducting high gradient magnetic separation with ferromagnetic adsorbent

    Science.gov (United States)

    Ishiwata, T.; Miura, O.; Hosomi, K.; Shimizu, K.; Ito, D.; Yoda, Y.

    2010-11-01

    Prevention of eutrophication for semi-enclosed bays and ponds is serious and important challenge. In spite of the advanced wastewater treatment, typically 1 mg/L phosphorus is discharged into public water bodies from wastewater treatment plants. The total amount of the discharged water is so large that the further improvement of the removal efficiency of phosphorus in the discharged water is demanded. On the other hand, recently phosphorus has become increasingly recognized as the important strategic material due to the global food problem. Therefore, the recovery and recycling of phosphorus is also important issue. In this work, removal and recovery of phosphorus from treated wastewater by High Gradient Magnetic Separation (HGMS) with ferromagnetic zirconium ferrite adsorbent were studied. Phosphorus in the treated wastewater could be removed from 1.12 mg/L to 0.03 mg/L by the HGMS system with 500 mg/L zirconium ferrite adsorbent for 5 min in adsorption time. The magnetic separation speed achieved 1 m/s at 1 T which was necessary for practical use. We also confirmed that phosphorus could be desorbed from zirconium ferrite adsorbent by alkali treatment in a short time.

  4. Removal and recovery of phosphorus in wastewater by superconducting high gradient magnetic separation with ferromagnetic adsorbent

    International Nuclear Information System (INIS)

    Prevention of eutrophication for semi-enclosed bays and ponds is serious and important challenge. In spite of the advanced wastewater treatment, typically 1 mg/L phosphorus is discharged into public water bodies from wastewater treatment plants. The total amount of the discharged water is so large that the further improvement of the removal efficiency of phosphorus in the discharged water is demanded. On the other hand, recently phosphorus has become increasingly recognized as the important strategic material due to the global food problem. Therefore, the recovery and recycling of phosphorus is also important issue. In this work, removal and recovery of phosphorus from treated wastewater by High Gradient Magnetic Separation (HGMS) with ferromagnetic zirconium ferrite adsorbent were studied. Phosphorus in the treated wastewater could be removed from 1.12 mg/L to 0.03 mg/L by the HGMS system with 500 mg/L zirconium ferrite adsorbent for 5 min in adsorption time. The magnetic separation speed achieved 1 m/s at 1 T which was necessary for practical use. We also confirmed that phosphorus could be desorbed from zirconium ferrite adsorbent by alkali treatment in a short time.

  5. Development program for magnetically assisted chemical separation: Evaluation of cesium removal from Hanford tank supernatant

    International Nuclear Information System (INIS)

    Magnetic particles (MAG*SEPSM) coated with various absorbents were evaluated for the separation and recovery of low concentrations of cesium from nuclear waste solutions. The MAG*SEPSM particles were coated with (1) clinoptilolite, (2) transylvanian volcanic tuff, (3) resorcinol formaldehyde, and (4) crystalline silico-titanate, and then were contacted with a Hanford supernatant simulant. Particles coated with the crystalline silico-titanate were identified by Bradtec as having the highest capacity for cesium removal under the conditions tested (variation of pH, ionic strength, cesium concentration, and absorbent/solution ratio). The MAG*SEPSM particles coated with resorcinol formaldehyde had high distribution ratios values and could also be used to remove cesium from Hanford supernant simulant. Gamma irradiation studies were performed on the MAG*SEPSM particles with a gamma dose equivalent to 100 cycles of use. This irradiation decreased the loading capacity and distribution ratios for the particles by greater than 75%. The particles demonstrated high sensitivity to radiolytic damage due to the degradation of the polymeric regions. These results were supported by optical microscopy measurements. Overall, use of magnetic particles for cesium separation under nuclear waste conditions was found to be marginally effective

  6. Development of high gradient magnetic separation system for removing the metallic wear debris to be present in highly viscous fluid

    Science.gov (United States)

    Hayashi, S.; Mishima, F.; Akiyama, Y.; Nishijima, S.

    2010-11-01

    In the industrial plants processing highly viscous fluid such as foods or industrial materials, there is an issue of contamination by metallic wear debris originating from pipe of manufacturing line. It is necessary to remove the metallic wear debris in highly viscous fluid, since these debris causes quality loss. In this study, we developed a high gradient magnetic separation system by using superconducting magnet to remove the metallic wear debris. The particle trajectory simulation and the magnetic separation experiment were conducted with polyvinyl alcohol as a model material. As a result, ca. 100% and 92.2% of the separation efficiency was achieved respectively for the highly viscous fluid of 1 Pa s and 6 Pa s in viscosity, with 14 and 30 mesh magnetic filters.

  7. Development of high gradient magnetic separation system for removing the metallic wear debris to be present in highly viscous fluid

    International Nuclear Information System (INIS)

    In the industrial plants processing highly viscous fluid such as foods or industrial materials, there is an issue of contamination by metallic wear debris originating from pipe of manufacturing line. It is necessary to remove the metallic wear debris in highly viscous fluid, since these debris causes quality loss. In this study, we developed a high gradient magnetic separation system by using superconducting magnet to remove the metallic wear debris. The particle trajectory simulation and the magnetic separation experiment were conducted with polyvinyl alcohol as a model material. As a result, ca. 100% and 92.2% of the separation efficiency was achieved respectively for the highly viscous fluid of 1 Pa s and 6 Pa s in viscosity, with 14 and 30 mesh magnetic filters.

  8. Effect of microwave irradiation on selective heating behavior and magnetic separation characteristics of Panzhihua ilmenite

    Energy Technology Data Exchange (ETDEWEB)

    Zhao, Wei; Chen, Jin; Chang, Xiaodong; Guo, Shenghui [National Local Joint Laboratory of Engineering Application of Microwave Energy and Equipment Technology, Faculty of Metallurgical and Energy Engineering, Kunming University of Science and Technology, Kunming 650093 (China); Srinivasakannan, C. [Chemical Engineering Program, The Petroleum Institute, Abu Dhabi, P.O. Box 253 (United Arab Emirates); Chen, Guo, E-mail: guochen@kmust.edu.cn [National Local Joint Laboratory of Engineering Application of Microwave Energy and Equipment Technology, Faculty of Metallurgical and Energy Engineering, Kunming University of Science and Technology, Kunming 650093 (China); Chemical Engineering Program, The Petroleum Institute, Abu Dhabi, P.O. Box 253 (United Arab Emirates); Peng, Jinhui, E-mail: jhpeng@kmust.edu.cn [National Local Joint Laboratory of Engineering Application of Microwave Energy and Equipment Technology, Faculty of Metallurgical and Energy Engineering, Kunming University of Science and Technology, Kunming 650093 (China); Chemical Engineering Program, The Petroleum Institute, Abu Dhabi, P.O. Box 253 (United Arab Emirates)

    2014-05-01

    Highlights: • Microwave irradiation can be applied effectively and efficiently to the irradiation processes of Panzhihua ilmenite. • The mineral processing properties of microwave treated ilmenite were generally as good as or better than that of initial ilmenite. • The microwave selective heating characteristics of the different minerals and compounds, and the thermal stresses were caused by the uniform heat rate disturbed under microwave irradiation. - Abstract: The influences of microwave irradiation on the surface characteristics of Panzhihua ilmenite were systematically investigated. The crystal structures, surface morphology and surface chemical functional groups of ilmenite were characterized before and after microwave irradiation and magnetic separation for different microwave treatment times by using various methods, such as XRD, SEM, and FT-IR, respectively. XRD analysis showed that the microwave treated ilmenite has the strongest peaks of phase more than that of raw samples, indicates that the crystalline compound of ilmenite increased with the microwave irradiation time. SEM analysis showed the micro-cracking appeared at many grain boundaries of ilmenite after being pretreated by microwave treatment. The separations of ilmenite from gangue minerals were completed and the micro-fissure within ilmenite minerals were also formed, which could be attributed to the microwave selective heating characteristics of the different minerals and compounds, and the thermal stresses were caused by the uniform heat rate disturbed under microwave irradiation. The mineral processing results showed that the magnetic separation characteristics and properties of microwave treated ilmenite samples were better than that of microwave untreated ilmenite samples. It was concluded that microwave irradiation can be applied effectively and efficiently to the irradiation processes of Panzhihua ilmenite.

  9. Effect of microwave irradiation on selective heating behavior and magnetic separation characteristics of Panzhihua ilmenite

    International Nuclear Information System (INIS)

    Highlights: • Microwave irradiation can be applied effectively and efficiently to the irradiation processes of Panzhihua ilmenite. • The mineral processing properties of microwave treated ilmenite were generally as good as or better than that of initial ilmenite. • The microwave selective heating characteristics of the different minerals and compounds, and the thermal stresses were caused by the uniform heat rate disturbed under microwave irradiation. - Abstract: The influences of microwave irradiation on the surface characteristics of Panzhihua ilmenite were systematically investigated. The crystal structures, surface morphology and surface chemical functional groups of ilmenite were characterized before and after microwave irradiation and magnetic separation for different microwave treatment times by using various methods, such as XRD, SEM, and FT-IR, respectively. XRD analysis showed that the microwave treated ilmenite has the strongest peaks of phase more than that of raw samples, indicates that the crystalline compound of ilmenite increased with the microwave irradiation time. SEM analysis showed the micro-cracking appeared at many grain boundaries of ilmenite after being pretreated by microwave treatment. The separations of ilmenite from gangue minerals were completed and the micro-fissure within ilmenite minerals were also formed, which could be attributed to the microwave selective heating characteristics of the different minerals and compounds, and the thermal stresses were caused by the uniform heat rate disturbed under microwave irradiation. The mineral processing results showed that the magnetic separation characteristics and properties of microwave treated ilmenite samples were better than that of microwave untreated ilmenite samples. It was concluded that microwave irradiation can be applied effectively and efficiently to the irradiation processes of Panzhihua ilmenite

  10. A chemically functionalized magnetic nanoplatform for rapid and specific biomolecular recognition and separation.

    Science.gov (United States)

    Lin, Po-Chiao; Yu, Ching-Ching; Wu, Huan-Ting; Lu, Ying-Wei; Han, Chia-Li; Su, An-Kai; Chen, Yu-Ju; Lin, Chun-Cheng

    2013-01-14

    We have developed a target-molecule-functionalized magnetic nanoparticle (MNP)-based method to facilitate the study of biomolecular recognition and separation. The superparamagnetic property of MNPs allows the corresponding biomolecules to be rapidly separated from crude biofluids with a significant improvement in recovery yield and specificity. Various MNPs functionalized with tag molecules (chitin, heparin, and amylose) were synthesized for recombinant protein purification, and several probe-functionalized MNPs, such as nitrilotriacetic acid (NTA)@MNP and P(k)@MNP, exhibited excellent extraction efficiency for proteins. In a cell recognition study, mannose-functionalized MNPs allowed specific purification of Escherichia coli with FimH adhesin on the surface. In an immunoprecipitation assay, the antibody-conjugated MNPs reduced the incubation time from 12 to 1 h while maintaining a comparable efficiency. The functionalized MNPs were also used in a membrane proteomic study that utilized the interaction between streptavidin-functionalized MNPs and biotinylated cell membrane proteins. Overall, the functionalized MNPs were demonstrated to be promising probes for the specific separation of targets from proteins to cells and proteomics. PMID:23198853

  11. Mass separation of a multi-component plasma flow travelling through a magnetic transport system

    Energy Technology Data Exchange (ETDEWEB)

    Paperny, V L; Krasov, V I [Physics Department, Irkutsk State University, Irkutsk, K. Marx Str., 1, 664003, Irkutsk (Russian Federation); Lebedev, N V; Astrakchantsev, N V [Institute for Physics and Technology, Irkutsk State Technical University, Irkutsk, Lermontov Str., 83, 664074, Irkutsk (Russian Federation)

    2011-06-15

    The travel of plasma flow produced by a dc arc through a transport system based on a curved magnetic field was studied. The characteristics of the system were the absence of a curved metallic plasma guiding duct ('open architecture') and the fact that the magnetic field coils were non-coaxial to the plasma flow. By means of Langmuir probe measurements it was shown that both shape and position of the cathode plasma flow at the exit of the transport system were governed by variation of currents of the magnetic coils as well as by biasing of a special electrode inserted into the plasma flow. It was found that with parameters of the transport system held constant, the plasma ions with lower m/Z were deflected more, e.g. Al ions were deflected more than Ti ions. For an arc with a composite cathode, consisting of mainly Cr-Fe-Ni, the profile of atoms of these elements at the exit of the transport system was measured by x-ray fluorescence spectrometry. The results obtained were consistent with the probe measurements, hence the transport system, in principle, may be used for spatial separation of a multi-component (in masses) plasma flow.

  12. Development of superconducting magnets for LHC luminosity upgrade (2). Conceptual design of a large aperture dipole magnet for beam separation

    International Nuclear Information System (INIS)

    Upgrade of the low-beta insertion system for the ATLAS and CMS experiments is proposed in the HL-LHC (High Luminosity LHC upgrade) project. It includes the final beam focusing quadrupoles, beam separation and recombination dipoles, and larger aperture matching section quadrupoles. KEK is in charge of conceptual design of the large aperture separation dipole D1. Latest design parameters are a main field of ?5 T at 1.9 K with Nb-Ti superconducting technology, a coil aperture of 160 mm, and a cos-theta 1-layer coil with LHC dipole cable. Since the new D1 is expected to be operated in very high-radiation environment, radiation resistance and cooling scheme are being carefully considered. The collaring-yoke structure is adopted to provide the mechanical support for the single layer Nb-Ti coil. We summarize the design study of this magnet, including (1) the very large iron saturation effect on field quality due to the large aperture and limited size of the iron yoke, (2) the stray field at the outer surface of the iron cryostat, (3) the stress management from room temperature assembly to final operation, and (4) the high-level of heat deposition in the coil due to radiation. (author)

  13. Research on high gradient magnetic separation of pneumatic conveyed powder products: Investigation from the viewpoint of interparticle interactions

    International Nuclear Information System (INIS)

    Highlights: ? We separated SUS particle from the mixture of alumina/silica and SUS particle. ? The high separation efficiencies were obtained both in two samples. ? The separation efficiency of the sample using alumina did not reach to 100%. ? The adhesion forces between particles were measured when changing the humidity. ? Based on these data, the conditions of the separation experiment were examined. -- Abstract: The separation and removal of the metallic debris originating from pipe of manufacturing line are required in the manufacturing process of the fine particle products. In this study, we develop a high gradient magnetic separation system (HGMS) under a dry process by using a superconducting magnet to remove ferromagnetic particles such as the material stainless steel (SUS). To avoid the obstruction of the separation part by aggregation of the processed material, we develop a magnetic separation system using a pneumatic conveying as a new transportation method of the particles. The magnetic separations were experimented under the same conditions on different days, but the results were different. The reason is considered to be the difference in adhesion force between the particles due to a change of humidity, we have measured the adhesion forces between the ferromagnetic particles and the paramagnetic medium particles using AFM (Atomic Force Microscope) while changing the humidity. As a result, the adhesion force between the particles increased with the increasing of humidity. Furthermore, we saw that the effect of relative humidity was larger in the adhesion force of alumina with larger cohesive property. Based on these results, an appropriate condition of the separation experiment was clarified. And a dehumidification mechanism was introduced

  14. Superconducting Open-Gradient Magnetic Separation for the Pretreatment of Radioactive or Mixed Waste Vitrification Feeds

    International Nuclear Information System (INIS)

    An open-gradient magnetic separation (OGMS) process is being considered to separate deleterious elements from radioactive and mixed waste streams prior to vitrification or stabilization. By physically segregating solid wastes and slurries based on the magnetic properties of the solid constituents, this potentially low-cost process may serve the U.S. Department of Energy (DOE) by reducing the large quantities of glass produced from defense-related high-level waste (HLW). Furthermore, the separation of deleterious elements from low-level waste (LLW) also can reduce the total quantity of waste produced in LLW immobilization activities. Many HLW 'and LLW waste' streams at both Hanford and the Savannah River Site (SRS) include constituents deleterious to the durability of borosilicate glass and the melter many of the constituents also possess paramagnetism. For example, Fe, Cr, Ni, and other transition metals may limit the waste loading and affect the durability of the glass by forming spine1 phases at the high operating temperature used in vitrification. Some magnetic spine1 phases observed in glass formation are magnetite (Fe,O,), chromite (FeCrO,), and others [(Fe, Ni, Mg, Zn, Mn)(Al, Fe, Ti, Cr)O,] as described elsewhere [Bates-1994, Wronkiewicz-1994]. Stable spine1 phases can cause segregation between the glass and the crystalline phases. As a consequence of the difference in density, the spine1 phases tend to accumulate at the bottom of the glass melter, which decreae bottom of the glass melter, which decreases the conductivity and melter lifetime [Sproull-1993]. Crystallization also can affect glass durability [Jantzen-1985, Turcotte- 1979, Buechele-1990] by changing the chemical composition of the matrix glass surrounding the crystals or causing stress at the glass/crystal interface. These are some of the effects that can increase leaching [Jantzen-1985]. A SRS glass that was partially crystallized to contain 10% vol. crystals composed of spinels, nepheline, and acmite phases showed minimal changes in short term leachability [Jantzen-1985, Hench-1982]. However, Jantzen et.al. found that leaching increased preferentially at grain boundary interfaces [Jantzen-1985]. For a SRL 165 glass crystallized up to 30% vol., leachability measured by normalized boron release increased by a factor of three compared to the uncrystallized glass [Kelly-1975, Plodinec-1979]. In general, the magnitude of the crystallization effect depends highly on glass composition and cooling rate

  15. Research on high gradient magnetic separation of pneumatic conveyed powder products: Investigation from the viewpoint of interparticle interactions

    Science.gov (United States)

    Senkawa, Kohei; Nakai, Yuki; Mishima, Fumihito; Akiyama, Yoko; Nishijima, Shigehiro

    2013-01-01

    The separation and removal of the metallic debris originating from pipe of manufacturing line are required in the manufacturing process of the fine particle products. In this study, we develop a high gradient magnetic separation system (HGMS) under a dry process by using a superconducting magnet to remove ferromagnetic particles such as the material stainless steel (SUS). To avoid the obstruction of the separation part by aggregation of the processed material, we develop a magnetic separation system using a pneumatic conveying as a new transportation method of the particles. The magnetic separations were experimented under the same conditions on different days, but the results were different. The reason is considered to be the difference in adhesion force between the particles due to a change of humidity, we have measured the adhesion forces between the ferromagnetic particles and the paramagnetic medium particles using AFM (Atomic Force Microscope) while changing the humidity. As a result, the adhesion force between the particles increased with the increasing of humidity. Furthermore, we saw that the effect of relative humidity was larger in the adhesion force of alumina with larger cohesive property. Based on these results, an appropriate condition of the separation experiment was clarified. And a dehumidification mechanism was introduced.

  16. Pade-Froissart exact signal-noise separation in nuclear magnetic resonance spectroscopy

    Energy Technology Data Exchange (ETDEWEB)

    Belkic, Dzevad; Belkic, Karen, E-mail: Dzevad.Belkic@ki.se [Karolinska Institute, PO Box 260, S-171 76 Stockholm (Sweden)

    2011-06-28

    Nuclear magnetic resonance spectroscopy is one of the key methods for studying the structure of matter on different levels (sub-nuclear, nuclear, atomic, molecular, cellular, etc). Its overall success critically depends upon reliable mathematical analysis and interpretation of the studied data. This is especially aided by parametric signal processing with the ensuing data quantification, which can yield the abundance or concentrations of the constituents in the examined matter. The sought reliability of signal processing rests upon the possibility of an accurate solution of the quantification problem alongside the unambiguous separation of true from false information in the spectrally analysed data. We presently demonstrate that the fast Pade transform (FPT), as the unique ratio of two polynomials for a given Maclaurin series, can yield exact signal-noise separation for a synthesized free induction decay curve built from 25 molecules. This is achieved by using the concept of Froissart doublets or pole-zero cancellations. Unphysical/spurious (noise or noise-like) resonances have coincident or near-coincident poles and zeros. They possess either zero- or near-zero-valued amplitudes. Such spectral structures never converge due to their instability against even the smallest perturbations. By contrast, upon convergence of the FPT, physical/genuine resonances are identified by their persistent stability against external perturbations, such as signal truncation or addition of random noise, etc. In practice, the computation is carried out by gradually and systematically increasing the common degree of the Pade numerator and denominator polynomials in the diagonal FPT. As this degree changes, the reconstructed parameters and spectra fluctuate until stabilization occurs. The polynomial degree at which this full stabilization is achieved represents the sought exact number of resonances. An illustrative set of results is reported in this work to show the exact separation of genuine from spurious information by reliance upon Froissart doublets and stabilization of reconstructions. The FPT for optimal quantification of the physical constituents of the studied matter and the denoising Froissart filter for unequivocal signal-noise separation is expected to significantly aid nuclear magnetic resonance spectroscopy in achieving the most reliable data analysis and interpretation.

  17. Padé-Froissart exact signal-noise separation in nuclear magnetic resonance spectroscopy

    Science.gov (United States)

    Belki?, Dževad; Belki?, Karen

    2011-06-01

    Nuclear magnetic resonance spectroscopy is one of the key methods for studying the structure of matter on different levels (sub-nuclear, nuclear, atomic, molecular, cellular, etc). Its overall success critically depends upon reliable mathematical analysis and interpretation of the studied data. This is especially aided by parametric signal processing with the ensuing data quantification, which can yield the abundance or concentrations of the constituents in the examined matter. The sought reliability of signal processing rests upon the possibility of an accurate solution of the quantification problem alongside the unambiguous separation of true from false information in the spectrally analysed data. We presently demonstrate that the fast Padé transform (FPT), as the unique ratio of two polynomials for a given Maclaurin series, can yield exact signal-noise separation for a synthesized free induction decay curve built from 25 molecules. This is achieved by using the concept of Froissart doublets or pole-zero cancellations. Unphysical/spurious (noise or noise-like) resonances have coincident or near-coincident poles and zeros. They possess either zero- or near-zero-valued amplitudes. Such spectral structures never converge due to their instability against even the smallest perturbations. By contrast, upon convergence of the FPT, physical/genuine resonances are identified by their persistent stability against external perturbations, such as signal truncation or addition of random noise, etc. In practice, the computation is carried out by gradually and systematically increasing the common degree of the Padé numerator and denominator polynomials in the diagonal FPT. As this degree changes, the reconstructed parameters and spectra fluctuate until stabilization occurs. The polynomial degree at which this full stabilization is achieved represents the sought exact number of resonances. An illustrative set of results is reported in this work to show the exact separation of genuine from spurious information by reliance upon Froissart doublets and stabilization of reconstructions. The FPT for optimal quantification of the physical constituents of the studied matter and the denoising Froissart filter for unequivocal signal-noise separation is expected to significantly aid nuclear magnetic resonance spectroscopy in achieving the most reliable data analysis and interpretation.

  18. Pade-Froissart exact signal-noise separation in nuclear magnetic resonance spectroscopy

    International Nuclear Information System (INIS)

    Nuclear magnetic resonance spectroscopy is one of the key methods for studying the structure of matter on different levels (sub-nuclear, nuclear, atomic, molecular, cellular, etc). Its overall success critically depends upon reliable mathematical analysis and interpretation of the studied data. This is especially aided by parametric signal processing with the ensuing data quantification, which can yield the abundance or concentrations of the constituents in the examined matter. The sought reliability of signal processing rests upon the possibility of an accurate solution of the quantification problem alongside the unambiguous separation of true from false information in the spectrally analysed data. We presently demonstrate that the fast Pade transform (FPT), as the unique ratio of two polynomials for a given Maclaurin series, can yield exact signal-noise separation for a synthesized free induction decay curve built from 25 molecules. This is achieved by using the concept of Froissart doublets or pole-zero cancellations. Unphysical/spurious (noise or noise-like) resonances have coincident or near-coincident poles and zeros. They possess either zero- or near-zero-valued amplitudes. Such spectral structures never converge due to their instability against even the smallest perturbations. By contrast, upon convergence of the FPT, physical/genuine resonances are identified by their persistent stability against external perturbations, such as signal truncation or addition os, such as signal truncation or addition of random noise, etc. In practice, the computation is carried out by gradually and systematically increasing the common degree of the Pade numerator and denominator polynomials in the diagonal FPT. As this degree changes, the reconstructed parameters and spectra fluctuate until stabilization occurs. The polynomial degree at which this full stabilization is achieved represents the sought exact number of resonances. An illustrative set of results is reported in this work to show the exact separation of genuine from spurious information by reliance upon Froissart doublets and stabilization of reconstructions. The FPT for optimal quantification of the physical constituents of the studied matter and the denoising Froissart filter for unequivocal signal-noise separation is expected to significantly aid nuclear magnetic resonance spectroscopy in achieving the most reliable data analysis and interpretation.

  19. Photocatalytic degradation of methylene blue on magnetically separable MgFe2O4 under visible light irradiation

    International Nuclear Information System (INIS)

    A magnetically separable single-phase MgFe2O4 photocatalyst with a spinel crystal structure was synthesized by using the solid-state reaction method. The formation of spinel structure is confirmed by X-ray diffraction and Fourier transform infrared spectroscopy. The magnetic measurements showed that the photocatalyst material can be separated from water when an external magnetic field is added and redispersed into water solution after the external magnetic field is eliminated. It is one of the promising photocatalysts for waste water treatment. The photocatalytic activity of MgFe2O4 was investigated by using the photo-decomposition of methylene blue dye under visible light. The photoelectrochemical property of the MgFe2O4 was studied by measuring their photocurrent–potential behavior in 1 M NaOH electrolyte under AM 1.5100 mW cm?2 illumination. - Graphical abstract: Highly efficient magnetically separable MgFe2O4 photocatalyst for organic based impurities decomposition as well as for the production of H2 gas was synthesized and characterized successfully (a) MgFe2O4 photocatalyst in polluted water, (b) The photocatalyst (MgFe2O4) is being attracted toward magnetic field for separation, (c) Hysteresis loop of MgFe2O4 showing magnetic behavior. Highlights: ? New photocatalyst working in the visible range have been synthesized by facile cheap route. ? MgFe2O4 photocatalyst showed well defined magnetically separable behavior. ? Excellent water splitting characteristics to produce H2 was observed under visible light irradiation

  20. Studies of charge separation characteristics for higher density plasma in a direct energy converter using slanted cusp magnetic field

    International Nuclear Information System (INIS)

    In an advanced fusion, fusion-produced charged particles must be separated from each other for converting their kinetic energy to electricity. The CUSPDEC performs this function of separation and direct energy conversion of thermal components. This paper summarizes experimental works by using a small scale experimental device and these results as charge separation characteristics by slanted cusp magnetic field. When the incident plasma is low-density, the dependences of the separation efficiency on magnetic field strength, energy of electrons, and gradient of the field line are explained by the theory based on a single particle motion. In high density plasma, however, this theory cannot always be applied due to a self-induced field. In the experiment, as plasma density became higher, separation capability of the charged particles became lower although the efficiency of separation was improved with some extent by using slanted cusp magnetic field. The modification of the theory applicable for high density plasma and the effective factor corresponding to separation efficiency was required in the following research. (author)

  1. Actinide separation of high-level waste using solvent extractants on magnetic microparticles

    International Nuclear Information System (INIS)

    Polymeric-coated ferromagnetic particles with an absorbed layer of octyl(phenyl)-N,N-diisobutylcarbamoylmethylphosphine oxide (CMPO) diluted by tributyl phosphate (TBP) are being evaluated for application in the separation and the recovery of low concentrations of americium and plutonium from nuclear waste solutions. Due to their chemical nature, these extractants selectively complex americium and plutonium contaminants onto the particles, which can be recovered from the waste solution using a magnet. The effectiveness of the extractant-absorbed particles at removing transuranics (TRU) from simulated solutions and various nitric acid solutions was measured by gamma and liquid scintillation counting of plutonium and americium. The HNO3 concentration range was 0.01 M to 6M. The partition coefficients (Kd) for various actinides at 2M HNO3 were determined to be between 3,000 and 30,000. These values are larger than those projected for TRU recovery by traditional liquid/liquid extraction. Results from transmission electron microscopy indicated a large dependence of Kd on relative magnetite location within the polymer and the polymer surface area. Energy disperse spectroscopy demonstrated homogeneous metal complexation on the polymer surface with no metal clustering. The radiolytic stability of the particles was determined by using 60Co gamma irradiation under various conditions. The results showed that Kd more strongly depends on the nitric acid dissolution rate of the magnetite than the gamma irradiation dose. Results of actinide separation from simulated high-level waste representative of that at various DOE sites are also discussed

  2. Semi-continuous in situ magnetic separation for enhanced extracellular protease productionmodeling and experimental validation

    DEFF Research Database (Denmark)

    Cerff, M.; Scholz, A.

    2013-01-01

    In modern biotechnology proteases play a major role as detergent ingredients. Especially the production of extracellular protease by Bacillus species facilitates downstream processing because the protease can be directly harvested from the biosuspension. In situ magnetic separation (ISMS) constitutes an excellent adsorptive method for efficient extracellular protease removal during cultivation. In this work, the impact of semi?continuous ISMS on the overall protease yield has been investigated. Results reveal significant removal of the protease from Bacillus licheniformis cultivations. Bacitracin?functionalized magnetic particles were successfully applied, regenerated and reused up to 30 times. Immediate reproduction of the protease after ISMS proved the biocompatibility of this integrated approach. Six subsequent ISMS steps significantly increased the overall protease yield up to 98% because proteolytic degradation and potential inhibition of the protease in the medium could be minimized. Furthermore, integration of semi?continuous ISMS increased the overall process efficiency due to reduction of the medium consumption. Process simulation revealed a deeper insight into protease production, and was used to optimize ISMS steps to obtain the maximum overall protease yield. Biotechnol. Bioeng. 2013; 110: 2161–2172. © 2013 Wiley Periodicals, Inc.

  3. Recovery of metallic copper by integrated chemical reduction and high gradient magnetic separation.

    Science.gov (United States)

    Wu, Wan-I; Panchangam, Sri Chandana; Wu, Chung-Hsin; Hong, Andy P K; Lin, Cheng-Fang

    2011-01-01

    The recovery of metals from waste effluents is necessary for pollution prevention and sustainable practice. High gradient magnetic separation (HGMS) is seen as a viable method. We investigated the capture of valence copper from aqueous copper ion by HGMS in combination with a chemical reduction process. When a copper solution (3.9 or 15.6 mM) was exposed to excess of dithionite (mole ratio of 1:3) in the presence of ammonia (mole ratio of 4) and amended with MnCl2 (2.5 g/L) and the mixture passed through a flow reactor under a strong magnetic field (10000 Gauss), valence copper was obtained and captured in the reactor with well over 95% yields. The chemical reduction reactions were unaffected by the presence of MnCl2 while the amount of MnCl2 (0, 20 and 32 mM) has significantly varied the copper recovery efficiency, especially in the case of high initial copper ion concentration (15.6 mM). Formation of MnO2 flocs was found to have a detrimental effect on copper removal efficiency. The HGMS method offers a tool of resource recovery for copper from waste effluents. PMID:21879556

  4. Templated synthesis of monodisperse mesoporous maghemite/silica microspheres for magnetic separation of genomic DNA

    International Nuclear Information System (INIS)

    A novel method is described for the preparation of superparamagnetic mesoporous maghemite (?-Fe2O3)/silica (SiO2) composite microspheres to allow rapid magnetic separation of DNA from biological samples. With magnetite (Fe3O4) and silica nanoparticles as starting materials, such microspheres were synthesized by the following two consecutive steps: (1) formation of monodispersed organic/inorganic hybrid microspheres through urea-formaldedyde (UF) polymerization and (2) removal of the organic template and phase transformation of Fe3O4 to ?-Fe2O3 by calcination at elevated temperatures. The as-synthesized particles obtained by heating at temperature 300 deg. C feature spherical shape and uniform particle size (dparticle=1.72 ?m), high saturation magnetization (Ms=17.22 emu/g), superparamagnetism (Mr/Ms=0.023), high surface area (SBET=240 m2/g), and mesoporosity (dpore=6.62 nm). The composite microsphere consists of interlocked amorphous SiO2 nanoparticles, in which cubic ?-Fe2O3 nanocrystals are homogeneously dispersed and thermally stable against ?- to ?-phase transformation at temperatures up to 600 deg. C. With the exposed iron oxide nanoparticles coated with a thin layer of silica shell, the magnetic microspheres were used as a solid-phase adsorbent for raed as a solid-phase adsorbent for rapid extraction of genomic DNA from plant samples. The results show that the DNA templates isolated from pea and green pepper displayed single bands with molecular weights greater than 8 kb and A260/A280 values of 1.60-1.72. The PCR amplification of a fragment encoding the endogenous chloroplast ndhB gene confirmed that the DNA templates obtained were inhibitor-free and amenable to sensitive amplification-based DNA technologies.

  5. Templated synthesis of monodisperse mesoporous maghemite/silica microspheres for magnetic separation of genomic DNA

    Science.gov (United States)

    Chen, Feng; Shi, Ruobing; Xue, Yun; Chen, Lei; Wan, Qian-Hong

    2010-08-01

    A novel method is described for the preparation of superparamagnetic mesoporous maghemite (?-Fe 2O 3)/silica (SiO 2) composite microspheres to allow rapid magnetic separation of DNA from biological samples. With magnetite (Fe 3O 4) and silica nanoparticles as starting materials, such microspheres were synthesized by the following two consecutive steps: (1) formation of monodispersed organic/inorganic hybrid microspheres through urea-formaldedyde (UF) polymerization and (2) removal of the organic template and phase transformation of Fe 3O 4 to ?-Fe 2O 3 by calcination at elevated temperatures. The as-synthesized particles obtained by heating at temperature 300 °C feature spherical shape and uniform particle size ( dparticle=1.72 ?m), high saturation magnetization ( Ms=17.22 emu/g), superparamagnetism ( Mr/ Ms=0.023), high surface area ( SBET=240 m 2/g), and mesoporosity ( dpore=6.62 nm). The composite microsphere consists of interlocked amorphous SiO 2 nanoparticles, in which cubic ?-Fe 2O 3 nanocrystals are homogeneously dispersed and thermally stable against ?- to ?-phase transformation at temperatures up to 600 °C. With the exposed iron oxide nanoparticles coated with a thin layer of silica shell, the magnetic microspheres were used as a solid-phase adsorbent for rapid extraction of genomic DNA from plant samples. The results show that the DNA templates isolated from pea and green pepper displayed single bands with molecular weights greater than 8 kb and A260/ A280 values of 1.60-1.72. The PCR amplification of a fragment encoding the endogenous chloroplast ndhB gene confirmed that the DNA templates obtained were inhibitor-free and amenable to sensitive amplification-based DNA technologies.

  6. Optimized high gradient magnetic separation for isolation of Plasmodium-infected red blood cells

    Directory of Open Access Journals (Sweden)

    Chimma Pattamawan

    2010-02-01

    Full Text Available Abstract Background Highly purified infected red blood cells (irbc, or highly synchronized parasite cultures, are regularly required in malaria research. Conventional isolation and synchronization rely on density and osmotic fragility of irbc, respectively. High gradient magnetic separation (HGMS offers an alternative based on intrinsic magnetic properties of irbc, avoiding exposure to chemicals and osmotic stress. Successful HGMS concentration in malaria research was previously reported using polymer coated columns, while HGMS depletion has not been described yet. This study presents a new approach to both HGMS concentration and depletion in malaria research, rendering polymer coating unnecessary. Methods A dipole magnet generating a strong homogenous field was custom assembled. Polypropylene syringes were fitted with one-way stopcocks and filled with stainless steel wool. Rbc from Plasmodium falciparum cultures were resuspended in density and viscosity optimized HGMS buffers and HGMS processed. Purification and depletion results were analysed by flow cytometer and light microscopy. Viability was evaluated by calculating the infection rate after re-culturing of isolates. Results In HGMS concentration, purity of irbc isolates from asynchronous cultures consistently ranged from 94.8% to 98.4% (mean 95.7%. With further optimization, over 90% of isolated irbc contained segmented schizonts. Processing time was less than 45 min. Reinfection rates ranged from 21.0% to 56.4%. In HGMS depletion, results were comparable to treatment with sorbitol, as demonstrated by essentially identical development of cultures. Conclusion The novel HGMS concentration procedure achieves high purities of segmented stage irbc from standard asynchronous cultures, and is the first HGMS depletion alternative to sorbitol lysis. It represents a simple and highly efficient alternative to conventional irbc concentration and synchronization methods.

  7. Spatiotemporally separating electron and phonon thermal transport in L10 FePt films for heat assisted magnetic recording

    International Nuclear Information System (INIS)

    We report the spatio-temporal separation of electron and phonon thermal transports in nanostructured magnetic L10 FePt films at the nanometer length scale and the time domain of tens of picosecond, when heated with a pulsed laser. We demonstrate that lattice dynamics measured using the picosecond time-resolved laser pump/X-ray probe method on the FePt (002) and Ag (002) Bragg reflections from different layers provided the information of nanoscale thermal transport between the layers. We also describe how the electron and phonon thermal transports in nanostructured magnetic thin films were separated.

  8. Fabrication of chiral amino acid ionic liquid modified magnetic multifunctional nanospheres for centrifugal chiral chromatography separation of racemates.

    Science.gov (United States)

    Liu, Yating; Tian, Ailin; Wang, Xiong; Qi, Jing; Wang, Fengkang; Ma, Ying; Ito, Yoichiro; Wei, Yun

    2015-06-26

    As the rapid development of nanotechnology, the magnetic nanospheres modified with special chiral selective ligands show a great potentiality in enantiomeric separation. In this study, magnetic nanospheres modified with task-specific chiral ionic liquid were designed for the separation of chiral amino acids. These modified magnetic nanospheres were effective in a direct chiral separation of five racemic amino acids (d- and l-cysteine, d- and l-arginine, d- and l-leucine, d- and l-glutamine and d- and l-tryptophan). Furthermore, a new online method for complete separation of the enantiomers via the magnetic nanospheres was established with centrifugal chiral chromatography using a spiral tube assembly mounted on a type-J coil planet centrifuge. One kind of chiral compounds, d- and l-tryptophan was resolved well using this method. These results demonstrated that the modified nanospheres display a good chiral recognition ability, and can be used as a potential material for chiral separation of various racemates. PMID:25976126

  9. Removal of low concentration Cr(VI) from aqueous solution by magnetic-fluids fixed bed using the high gradient magnetic separation.

    Science.gov (United States)

    Wang, Qiang; Guan, Yueping; Ren, Xiufeng; Yang, Mingzhu; Liu, Xiang

    2012-05-15

    The focus of this paper was a novel model of Cr(VI) extraction process. The original so-called "magnetic-fluids fixed bed" (MFFB), which bridged the solvent extraction and the fixed-bed extraction by the theory of the high gradient magnetic separation (HGMS), has been explained. The MFFB integrated the advantages of the two above mentioned classical extraction methods and overcame their drawbacks. The feasibility of this method was studied by extraction experiments of Cr(VI) from aqueous solution. The influences of the design of ferromagnetic steel wires in magnetic separation column, the pH value of feed solution, TBP concentration in magnetic fluids, and flow rate of aqueous solution in column were investigated. Under the optimum conditions, the proposed method obtained high extraction efficiency with continuous process. PMID:22369980

  10. Formation and properties of magnetic chains for 100 nm nanoparticles used in separations of molecules and cells

    OpenAIRE

    Wilson, Robert J.; Hu, Wei; Fu, Cheryl Wong Po; Koh, Ai Leen; Gaster, Richard S.; Earhart, Christopher M.; Fu, Aihua; Heilshorn, Sarah C; Sinclair, Robert; Wang, Shan X.

    2009-01-01

    Optical observations of 100 nm metallic magnetic nanoparticles are used to study their magnetic field induced self assembly. Chains with lengths of tens of microns are observed to form within minutes at nanoparticle concentrations of 1010 per mL. Chain rotation and magnetophoresis are readily observed, and SEM reveals that long chains are not simple single particle filaments. Similar chains are detected for several 100 nm commercial bio-separation nanoparticles. We demonstrate the staged magn...

  11. Functional-integral approach to the investigation of the spin-spiral magnetic order and phase separation

    OpenAIRE

    Arzhnikov, Anatoly; Groshev, Andrey

    2011-01-01

    We investigate a two-dimensional single-band Hubbard model with a nearest-neighbor hopping. We treat a commensurate collinear order as well as incommensurate spiral magnetic phases at a finite temperature using a Hubbard-Stratonovich transformation with a two-field representation and solve this problem in a static approximation. We argue that temperature dramatically influence the collinear and spiral magnetic phases, phase separation in the vicinity of half-filling. The res...

  12. Effect of surface potential of small particles suspended in solution on separation characteristics in a HGMS (High Gradient Magnetic Separator)

    International Nuclear Information System (INIS)

    The effect of surface potential of particles on removal characteristics in the HGMS were studied by using three kinds of small particles with individually different magnetic susceptibility: molybdenum, chrominum and hematite. It was shown that the effect of surface potential of particles such as molybdenum with low magnetic susceptibility value less than 1.7 x 104 appeared at a low linear velocity of liquid less than 150 m/h, and the removal performance increased by controlling the pH range in which the product of ?-potential of the particle and matrix was negative. The relation between the particles volume captured with matrix and the rest potential of the matrix was determined. (author)

  13. Analytical description of the coefficient of demagnetization for chains of cores of granulesin the filter matrix of a magnetic separator ????????????? ???????? ???????????? ??????????????? ????????????? ????????? ??????? ?????? ??????-??????? ?????????? ??????????

    Directory of Open Access Journals (Sweden)

    Sandulyak Anna Aleksandrovna

    2013-09-01

    Full Text Available Particle capturing efficiency inside the filter matrix of a magnetic separator used in the treatment of ceramic suspensions, minerals, condensates, other liquids and gas depends immediately on the intensity of its magnetization capacity. Chains of granules of a filter matrix represent effective magnetization channels. Demagnetization intensity influences the magnetization intensity of the whole filter matrix and its separate chains that are also considered as magnetization channels. The pattern of calculation of demagnetization factor N (coefficient of demagnetization for such channel magnets is of utmost academic interest, and this pattern is provided in this article. The author provides values for demagnetization factor N for quasi solid cores ofchains of granules having with various lengths L and diameters d (metal concentra-tion 0.78—0.99, if magnetized by the field having the intensity of ? =18–175 k?/m. It isproven that the values of N and ? L / d have an exponential relation.Earlier, the author identified that the values of N for the porous media having a cylindrical form depend on the ratio of the length of magnet L to its diameter D . It is proven that the values of N and those of ? L / D also have an exponential relation. Therefore, this reciprocal conformity of relations in respect of the demagnetization factor for samples of the granulated medium (consisting of chains of magnets-channels and for cores of magnets-channels (having different porosity values has confirmed the similarity of the demagnetization factor for magnets having substantial and high concentration of the ferromagnetic material. The analytical description (the formula of the coefficient of demagnetization of channel cores is provided in the article.?????? ?? ???????????? ????????? ? ??????????? ?????????????? ??????????????? ????, ? ??????? ???????????? ???????????-???????? ???????? ??????? ?????????????? ??????, ?????????? ??????? ??????? ??????? ?????? ? ?????????? ????????????????? ??????? N ????? ???????. ????????? ???????? N ??? ????????????? ????????? ??????? ????????? ???? L ? ????????? d , ? ????? ????????? ??? N ? ?????????? ? ???? ???????? ?????????????? ???????? ?????????? ? L / d , ??? ????????? ??????????? ? ??????????? ?????????? ??? ??????? ??????????????? ????? (????????? ?? ????? ???????.

  14. Magnetic isotope and magnetic field effects on chemical reactions. Sunlight and soap for the efficient separation of 13C and 12C isotopes

    International Nuclear Information System (INIS)

    Photolysis of dibenzyl ketone (DBK) solution at room temperature yields 1,2-diphenylethane and carbon monoxide quantitatively. Results of the study of this reaction, using light and ordinary mercury lamps as excitation sources, show that (1) a measurable, but small, 12C/13C isotope separation occurs in homogeneous (benzene) solution; (2) the efficiency of the separation is greatly enhanced in soap solution relative to homogeneous solution; (3) the carbonyl carbon of DBK is specifically and exponentially enriched as photolysis proceeds; (4) an external magnetic field significantly influences the efficiency of the isotopic separation. Mass spectroscopic and NMR analyses of the recovered DBK confirm these conclusions. 2 figures

  15. Non-magnetic insulator state in Na1CoO2 and phase separation of Na vacancies

    OpenAIRE

    Vaulx, C.; Julien, M. -h; Berthier, C.; Horvatic, M.; Bordet, P.; Simonet, V.; Chen, D. P.; Lin, C. T.

    2005-01-01

    Crystallographic, magnetic and NMR properties of a NaxCoO2 single crystal with x~1 are presented. We identify the stoichiometric Na1CoO2 phase, which is shown to be a non-magnetic insulator, as expected for homogeneous planes of Co3+ ions with S=0. In addition, we present evidence that, because of slight average Na deficiency, chemical and electronic phase separation leads to a segregation of Na vacancies into the well-defined, magnetic, Na0.8CoO2 phase. The importance of ph...

  16. Magnetically separable nanocomposites with photocatalytic activity under visible light for the selective transformation of biomass-derived platform molecules

    Science.gov (United States)

    Novel magnetically separable TiO2-guanidine-(Ni,Co)Fe2O4 nanomaterials were prepared and characterised by a series of techniques including XRD, SEM, TEM, N2 physisorption as well as XPS and subsequently tested for their photocatalytic activities in the selective transformation of...

  17. Environmental friendly crush-magnetic separation technology for recycling metal-plated plastics from end-of-life vehicles.

    Science.gov (United States)

    Xue, Mianqiang; Li, Jia; Xu, Zhenming

    2012-03-01

    Metal-plated plastics (MPP), which are important from the standpoint of aesthetics or even performance, are increasingly employed in a wide variety of situations in the automotive industry. Serious environmental problems will be caused if they are not treated appropriately. Therefore, recycling of MPP is an important subject not only for resource recycling but also for environmental protection. This work represents a novel attempt to deal with the MPP. A self-designed hammer crusher was used to liberate coatings from the plastic substrate. The size distribution of particles was analyzed and described by the Rosin-Rammler function model. The optimum retaining time of materials in the crusher is 3 min. By this time, the liberation rate of the materials can reach 87.3%. When the density of the suspension is 31,250 g/m(3), the performance of liberation is the best. Two-step magnetic separation was adopted to avoid excessive crushing and to guarantee the quality of products. Concerning both the separation efficiency and grade of products, the optimum rotational speed of the magnetic separator is 50-70 rpm. On the basis of the above studies about the liberating and separating behavior of the materials, a continuous recycling system (the technology of crush-magnetic separation) is developed. This recycling system provides a feasible method for recycling MPP efficiently, economically, and environmentally. PMID:22304328

  18. Separation of species of a binary fluid mixture confined in a channel in presence of a strong transverse magnetic field

    Directory of Open Access Journals (Sweden)

    Sharma Bishwaram

    2012-01-01

    Full Text Available Effects of a transverse magnetic field on separation of a binary mixture of incompressible viscous thermally and electrically conducting fluids confined between two stationary parallel plates are examined. Both the plates are maintained at constant temperatures. It is assumed that one of the components, which is rarer and lighter, is present in the mixture in a very small quantity. The equations governing the motion, temperature and concentration in Cartesian coordinate are solved analytically. The solution obtained for concentration distribution is plotted against the width of the channel for various values of non-dimensional parameters. It is found that the effect of transverse magnetic field is to separate the species of rarer and lighter component by contributing its effect directly to the temperature gradient and the pressure gradient. The effects of increase in the values of Hartmann number, magnetic Reynolds number, barodiffusion number, thermal diffusion number, electric field parameter and the product of Prandtl number and Eckert number are to collect the rarer and lighter component near the upper plate and throw away the heavier component towards the lower plate. The problem discussed here derives its application in the basic fluid dynamics separation processes to separate the rare component of the different isotopes of heavier molecules where electromagnetic method of separation does not work.

  19. Novel magnetically separable AgCl/iron oxide composites with enhanced photocatalytic activity driven by visible light

    International Nuclear Information System (INIS)

    Highlights: •The AgCl/iron oxide composites were prepared by a chemical precipitation method. •The composites exhibited improved performances in the photodegradation of pollutants. •The visible light photocatalysts could be recycled easily by a magnet. -- Abstract: In this work, AgCl/iron oxide composites were synthesized by a simple chemical precipitation method and calcining process. The composition of the material and magnetic and optical properties of the composites were studied by X-ray diffraction (XRD), scanning electron microscopy (SEM), transmission electron microscopy (TEM) and vibrating specimen magnetometer (VSM) techniques, which confirms the high crystalline and magnetic behavior of the composites. UV-vis diffuse reflectance spectral (DRS) studies showed that the AgCl/iron oxide composites were of much higher absorption in longer wavelength region compared to bare iron oxide. The AgCl/iron oxide composites showed better performance in the photodegradation of organic dyes Rhodamin B (RhB) under the fluorescent lamp irradiation, which is remarkably superior to the N-TiO2. The degradation of microcystin-LR (MC-LR) and phenol was also found to be good owing to its effective electron-hole separation at AgCl/iron oxide interface. The separation of AgCl/iron oxide composites from the treated water was achieved by an external magnetic field as ?-Fe2O3 exhibits enough magnetic power to facilitate the separation

  20. Use of the high-gradient magnetic separation on processing of mineral and man-caused raw stock

    International Nuclear Information System (INIS)

    The role and the value of a high-gradient magnetic separation process in the improvement of concentration and hydrometallurgical processing of noble, non-ferrous, rare and radioactive metal ores are under consideration. The results of research and experiments are presented which are carried out by the laboratory of magnetic separation and special methods of ore enrichment the All-Russian Research Institute of Chemical Technology with the aim of development and introduction into the industry of ore processing technology for uranium, gold, nonferrous and rare metal bearing ores, quarts-feldspar as well as technogenic waste processing. The most promising applications of magnetic methods are determined. The unique methodological and technical achievements are offered for use

  1. Chemical interferences when using high gradient magnetic separation for phosphate removal: consequences for lake restoration.

    Science.gov (United States)

    de Vicente, I; Merino-Martos, A; Guerrero, F; Amores, V; de Vicente, J

    2011-09-15

    A promising method for lake restoration is the treatment of lake inlets through the specific adsorption of phosphate (P) on strongly magnetizable particles (Fe) and their subsequent removal using in-flow high gradient magnetic separation (HGMS) techniques. In this work, we report an extensive investigation on the chemical interferences affecting P removal efficiencies in natural waters from 20 Mediterranean ponds and reservoirs. A set of three treatments were considered based on different Fe particles/P concentration ratios. High P removal efficiencies (>80%) were found in freshwater lakes (conductivitieshigh mineralized waters. Correlation analysis showed that major cations (Mg(2+), Na(+) and K(+)) and anions (SO(4)(2-) and Cl(-)) played an essential role in P removal efficiency. Comparison between different treatments have shown that when increasing P and Fe concentrations at the same rate or when increasing Fe concentrations for a fixed P concentration, there exist systematic reductions in the slope of the regression lines relating P removal efficiency and the concentration of different chemical variables. These results evidence a general reduction in the chemical competition between P and other ions for adsorption sites on Fe particles. Additional analyses also revealed a reduction in water color, dissolved organic carbon (DOC) and reactive silicate (Si) concentrations with the addition of Fe microparticles. PMID:21741173

  2. Determination of nanoparticle force balance in an electrical magnetic separation system

    Directory of Open Access Journals (Sweden)

    E.E. Volkanin

    2014-04-01

    Full Text Available Analytical expressions for magnetic force gradient computation are given. FEM simulation of the matrix core in the working gap of a magnetic system is conducted. The magnetic force distribution is presented as a relative ratio. A force balance equation taking into account the magnetic force pattern is derived.

  3. Neutron scattering evidence for magnetic-field-driven abrupt magnetic and structural transitions in a phase-separated manganite

    Science.gov (United States)

    Yaicle, C.; Martin, C.; Jirak, Z.; Fauth, F.; André, G.; Suard, E.; Maignan, A.; Hardy, V.; Retoux, R.; Hervieu, M.; Hébert, S.; Raveau, B.; Simon, Ch.; Saurel, D.; Brûlet, A.; Bourée, F.

    2003-12-01

    Substitutions at the Mn site of the charge-ordered Pr0.5Ca0.5MnO3 manganite is an effective way to induce abrupt jumps on the magnetic-field-driven magnetization curve. In order to get new insights into the origin of this remarkable feature, the Pr0.5Ca0.5Mn0.97Ga0.03O3 perovskite manganite has been studied by neutron diffraction versus temperature and at 2.5 K in an applied magnetic field up to 6 T. A weak and complex antiferromagnetic order is found for the low-temperature ground state. Magnetic transitions, associated with structural ones, are evidenced for certain strengths of magnetic field, which gives rise to the steplike behavior corresponding to the magnetization curve. Small-angle neutron scattering provides evidence for a nucleation process of micron-size ferromagnetic domains which follows the magnetization behavior.

  4. Boundary-value problem for a counterrotating electrical discharge in an axial magnetic field. [plasma centrifuge for isotope separation

    Science.gov (United States)

    Hong, S. H.; Wilhelm, H. E.

    1978-01-01

    An electrical discharge between two ring electrodes embedded in the mantle of a cylindrical chamber is considered, in which the plasma in the anode and cathode regions rotates in opposite directions under the influence of an external axial magnetic field. The associated boundary-value problem for the coupled partial differential equations describing the azimuthal velocity and radial current-density fields is solved in closed form. The velocity, current density, induced magnetic induction, and electric fields are presented for typical Hartmann numbers, magnetic Reynolds numbers, and geometry parameters. The discharge is shown to produce anodic and cathodic plasma sections rotating at speeds of the order 1,000,000 cm/sec for conventional magnetic field intensities. Possible application of the magnetoactive discharge as a plasma centrifuge for isotope separation is discussed.

  5. Superconducting open-gradient magnetic separation for the pretreatment of radioactive or mixed waste vitrification feeds. 1997 annual progress report

    International Nuclear Information System (INIS)

    'Vitrification has been selected as a final waste form technology in the US for long-term storage of high-level radioactive wastes (HLW). However, a foreseeable problem during vitrification in some waste feed streams lies in the presence of elements (e.g., transition metals) in the HLW that may cause instabilities in the final glass product. The formation of spinel compounds, such as Fe3O4 and FeCrO4, results in glass phase separation and reduces vitrifier lifetime, and durability of the final waste form. A superconducting open gradient magnetic separation (OGMS) system maybe suitable for the removal of the deleterious transition elements (e.g. Fe, Co, and Ni) and other elements (lanthanides) from vitrification feed streams due to their ferromagnetic or paramagnetic nature. The OGMS systems are designed to deflect and collect paramagnetic minerals as they interact with a magnetic field gradient. This system has the potential to reduce the volume of HLW for vitrification and ensure a stable product. In order to design efficient OGMS and High gradient magnetic separation (HGMS) processes, a fundamental understanding of the physical and chemical properties of the waste feed streams is required. Using HLW simulant and radioactive fly ash and sludge samples from the Savannah River Technology Center, Rocky Flats site, and the Hanford reservation, several techniques were used to characterize and predict the separation capability for a superconducting OGMS system.'

  6. Beta-NMR magnetic moment measurements using on-line mass separation and tilted-foil polarization

    International Nuclear Information System (INIS)

    The methods of tilted foil nuclear polarization and on-line mass separation have for the first time been successfully applied to a Beta-Nuclear Magnetic Resonance (?-NMR) technique for measuring multipole moments of ?-unstable nuclei. The magnetic moment of 33Cl (T/sub 1/2/ = 2.51 s, I/sup ?/ = 3/2+), the mirror nucleus of 33S, was successfully measured using this arrangement. Following production by nuclear reaction, recoiling nuclei were mass separated by the Recoil Mass Spectrometer (RMS) after which they were polarized by passage through an array of tilted carbon foils, and implanted in a catcher. Nuclear polarization, monitored by detection of asymmetric ?-emission, was destroyed via resonant rf excitation to locate the nuclear magnetic resonance, which was marked by a disappearance of the decay anisotropy. Tests were performed with 12B (T/sub 1/2/ = 20.4 ms, I/sup ?/ = 1+) which were produced via the d(11B,12B)p reaction, and implanted in Au. The 33Cl nuclei were produced via the d(32S,33Cl)n reaction, and implanted in a NaCl single crystal. The ground-state magnetic moment of 33Cl, corrected for diamagnetism, is ? = +0.7523(16) ?/sub n/. The results for the mass 33 mirror shell pair are discussed in terms of three separate theoretical analyses of sd-shell mirror nuclei

  7. Separation Anxiety

    Science.gov (United States)

    Julie Yu

    2007-01-01

    In this activity, learners discover the primary physical properties used to separate pure substances from mixtures. Learners use test tubes, beakers, magnets, and other tools to separate a mixture of sand, iron filings, salt, popcorn kernels, and poppyseeds. This activity introduces learners to the basic properties of size, magnetism, density and solubility while emphasizing that chemistry involves separating out substances either to understand what they are or to use the pure components to create new substances.

  8. Superconductivity and magnetism in RbxFe2-ySe2: Impact of thermal treatment on mesoscopic phase separation

    OpenAIRE

    Weyeneth, S.; Bendele, M.; Von Rohr, F.; Dluzewski, P.; Puzniak, R.; Krzton-maziopa, A.; Bosma, S.; Guguchia, Z.; Khasanov, R.; Shermadini, Z.; Amato, A.; Pomjakushina, E.; Conder, K.; Schilling, A.; Keller, H.

    2012-01-01

    An extended study of the superconducting and normal-state properties of various as-grown and post-annealed RbxFe2-ySe2 single crystals is presented. Magnetization experiments evidence that annealing of RbxFe2-ySe2 at 413 K, well below the onset of phase separation Tp=489 K, neither changes the magnetic nor the superconducting properties of the crystals. In addition, annealing at 563 K, well above Tp, suppresses the superconducting transition temperature Tc and leads to an in...

  9. Beam-energy dependence of charge separation along the magnetic field in Au+Au collisions at RHIC

    CERN Document Server

    Adamczyk, L; Agakishiev, G; Aggarwal, M M; Ahammed, Z; Alekseev, I; Alford, J; Anson, C D; Aparin, A; Arkhipkin, D; Aschenauer, E C; Averichev, G S; Banerjee, A; Beavis, D R; Bellwied, R; Bhasin, A; Bhati, A K; Bhattarai, P; Bichsel, H; Bielcik, J; Bielcikova, J; Bland, L C; Bordyuzhin, I G; Borowski, W; Bouchet, J; Brandin, A V; Brovko, S G; Bültmann, S; Bunzarov, I; Burton, T P; Butterworth, J; Caines, H; Sánchez, M Calderón de la Barca; Cebra, D; Cendejas, R; Cervantes, M C; Chaloupka, P; Chang, Z; Chattopadhyay, S; Chen, H F; Chen, J H; Chen, L; Cheng, J; Cherney, M; Chikanian, A; Christie, W; Chwastowski, J; Codrington, M J M; Contin, G; Cramer, J G; Crawford, H J; Cui, X; Das, S; Leyva, A Davila; De Silva, L C; Debbe, R R; Dedovich, T G; Deng, J; Derevschikov, A A; de Souza, R Derradi; Dhamija, S; di Ruzza, B; Didenko, L; Dilks, C; Ding, F; Djawotho, P; Dong, X; Drachenberg, J L; Draper, J E; Du, C M; Dunkelberger, L E; Dunlop, J C; Efimov, L G; Engelage, J; Engle, K S; Eppley, G; Eun, L; Evdokimov, O; Eyser, O; Fatemi, R; Fazio, S; Fedorisin, J; Filip, P; Finch, E; Fisyak, Y; Flores, C E; Gagliardi, C A; Gangadharan, D R; Garand, D; Geurts, F; Gibson, A; Girard, M; Gliske, S; Greiner, L; Grosnick, D; Gunarathne, D S; Guo, Y; Gupta, A; Gupta, S; Guryn, W; Haag, B; Hamed, A; Han, L-X; Haque, R; Harris, J W; Heppelmann, S; Hirsch, A; Hoffmann, G W; Hofman, D J; Horvat, S; Huang, B; Huang, H Z; Huang, X; Huck, P; Humanic, T J; Igo, G; Jacobs, W W; Jang, H; Judd, E G; Kabana, S; Kalinkin, D; Kang, K; Kauder, K; Ke, H W; Keane, D; Kechechyan, A; Kesich, A; Khan, Z H; Kikola, D P; Kisel, I; Kisiel, A; Koetke, D D; Kollegger, T; Konzer, J; Koralt, I; Kosarzewski, L K; Kotchenda, L; Kraishan, A F; Kravtsov, P; Krueger, K; Kulakov, I; Kumar, L; Kycia, R A; Lamont, M A C; Landgraf, J M; Landry, K D; Lauret, J; Lebedev, A; Lednicky, R; Lee, J H; LeVine, M J; Li, C; Li, W; Li, X; Li, Y; Li, Z M; Lisa, M A; Liu, F; Ljubicic, T; Llope, W J; Lomnitz, M; Longacre, R S; Luo, X; Ma, G L; Ma, Y G; Don, D M M D Madagodagettige; Mahapatra, D P; Majka, R; Margetis, S; Markert, C; Masui, H; Matis, H S; McDonald, D; McShane, T S; Minaev, N G; Mioduszewski, S; Mohanty, B; Mondal, M M; Morozov, D A; Mustafa, M K; Nandi, B K; Nasim, Md; Nayak, T K; Nelson, J M; Nigmatkulov, G; Nogach, L V; Noh, S Y; Novak, J; Nurushev, S B; Odyniec, G; Ogawa, A; Oh, K; Ohlson, A; Okorokov, V; Oldag, E W; Olvitt, D L; Pachr, M; Page, B S; Pal, S K; Pan, Y X; Pandit, Y; Panebratsev, Y; Pawlak, T; Pawlik, B; Pei, H; Perkins, C; Peryt, W; Pile, P; Planinic, M; Pluta, J; Poljak, N; Poniatowska, K; Porter, J; Poskanzer, A M; Pruthi, N K; Przybycien, M; Pujahari, P R; Putschke, J; Qiu, H; Quintero, A; Ramachandran, S; Raniwala, R; Raniwala, S; Ray, R L; Riley, C K; Ritter, H G; Roberts, J B; Rogachevskiy, O V; Romero, J L; Ross, J F; Roy, A; Ruan, L; Rusnak, J; Rusnakova, O; Sahoo, N R; Sahu, P K; Sakrejda, I; Salur, S; Sandweiss, J; Sangaline, E; Sarkar, A; Schambach, J; Scharenberg, R P; Schmah, A M; Schmidke, W B; Schmitz, N; Seger, J; Seyboth, P; Shah, N; Shahaliev, E; Shanmuganathan, P V; Shao, M; Sharma, B; Shen, W Q; Shi, S S; Shou, Q Y; Sichtermann, E P; Singaraju, R N; Skoby, M J; Smirnov, D; Smirnov, N; Solanki, D; Sorensen, P; Spinka, H M; Srivastava, B; Stanislaus, T D S; Stevens, J R; Stock, R; Strikhanov, M; Stringfellow, B; Sumbera, M; Sun, X; Sun, X M; Sun, Y; Sun, Z; Surrow, B; Svirida, D N; Symons, T J M; Szelezniak, M A; Takahashi, J; Tang, A H; Tang, Z; Tarnowsky, T; Thomas, J H; Timmins, A R; Tlusty, D; Tokarev, M; Trentalange, S; Tribble, R E; Tribedy, P; Trzeciak, B A; Tsai, O D; Turnau, J; Ullrich, T; Underwood, D G; Van Buren, G; van Nieuwenhuizen, G; Vandenbroucke, M; Vanfossen,, J A; Varma, R; Vasconcelos, G M S; Vasiliev, A N; Vertesi, R; Videbæk, F; Viyogi, Y P; Vokal, S; Vossen, A; Wada, M; Wang, F; Wang, G; Wang, H; Wang, J S; Wang, X L; Wang, Y; Webb, G; Webb, J C; Westfall, G D; Wieman, H; Wissink, S W; Witt, R; Wu, Y F; Xiao, Z; Xie, W; Xin, K; Xu, H; Xu, J; Xu, N; Xu, Q H; Xu, Y; Xu, Z; Yan, W; Yang, C; Yang, Y; Ye, Z; Yepes, P; Yi, L; Yip, K; Yoo, I-K; Yu, N; Zawisza, Y; Zbroszczyk, H; Zha, W; Zhang, J B; Zhang, J L; Zhang, S; Zhang, X P; Zhang, Y; Zhang, Z P; Zhao, F; Zhao, J; Zhong, C; Zhu, X; Zhu, Y H; Zoulkarneeva, Y; Zyzak, M

    2014-01-01

    Local parity-odd domains are theorized to form inside a Quark-Gluon-Plasma (QGP) which has been produced in high-energy heavy-ion collisions. The local parity-odd domains manifest themselves as charge separation along the magnetic field axis via the chiral magnetic effect (CME). The experimental observation of charge separation has previously been reported for heavy-ion collisions at the top RHIC energies. In this paper, we present the results of the beam-energy dependence of the charge correlations in Au+Au collisions at midrapidity for center-of-mass energies of 7.7, 11.5, 19.6, 27, 39 and 62.4 GeV from the STAR experiment. After background subtraction, the signal gradually reduces with decreased beam energy, and tends to vanish by 7.7 GeV. The implications of these results for the CME will be discussed.

  10. Beam-energy dependence of charge separation along the magnetic field in Au+Au collisions at RHIC.

    Science.gov (United States)

    Adamczyk, L; Adkins, J K; Agakishiev, G; Aggarwal, M M; Ahammed, Z; Alekseev, I; Alford, J; Anson, C D; Aparin, A; Arkhipkin, D; Aschenauer, E C; Averichev, G S; Banerjee, A; Beavis, D R; Bellwied, R; Bhasin, A; Bhati, A K; Bhattarai, P; Bichsel, H; Bielcik, J; Bielcikova, J; Bland, L C; Bordyuzhin, I G; Borowski, W; Bouchet, J; Brandin, A V; Brovko, S G; Bültmann, S; Bunzarov, I; Burton, T P; Butterworth, J; Caines, H; Calderón de la Barca Sánchez, M; Cebra, D; Cendejas, R; Cervantes, M C; Chaloupka, P; Chang, Z; Chattopadhyay, S; Chen, H F; Chen, J H; Chen, L; Cheng, J; Cherney, M; Chikanian, A; Christie, W; Chwastowski, J; Codrington, M J M; Contin, G; Cramer, J G; Crawford, H J; Cui, X; Das, S; Davila Leyva, A; De Silva, L C; Debbe, R R; Dedovich, T G; Deng, J; Derevschikov, A A; Derradi de Souza, R; Dhamija, S; di Ruzza, B; Didenko, L; Dilks, C; Ding, F; Djawotho, P; Dong, X; Drachenberg, J L; Draper, J E; Du, C M; Dunkelberger, L E; Dunlop, J C; Efimov, L G; Engelage, J; Engle, K S; Eppley, G; Eun, L; Evdokimov, O; Eyser, O; Fatemi, R; Fazio, S; Fedorisin, J; Filip, P; Finch, E; Fisyak, Y; Flores, C E; Gagliardi, C A; Gangadharan, D R; Garand, D; Geurts, F; Gibson, A; Girard, M; Gliske, S; Greiner, L; Grosnick, D; Gunarathne, D S; Guo, Y; Gupta, A; Gupta, S; Guryn, W; Haag, B; Hamed, A; Han, L-X; Haque, R; Harris, J W; Heppelmann, S; Hirsch, A; Hoffmann, G W; Hofman, D J; Horvat, S; Huang, B; Huang, H Z; Huang, X; Huck, P; Humanic, T J; Igo, G; Jacobs, W W; Jang, H; Judd, E G; Kabana, S; Kalinkin, D; Kang, K; Kauder, K; Ke, H W; Keane, D; Kechechyan, A; Kesich, A; Khan, Z H; Kikola, D P; Kisel, I; Kisiel, A; Koetke, D D; Kollegger, T; Konzer, J; Koralt, I; Kotchenda, L; Kraishan, A F; Kravtsov, P; Krueger, K; Kulakov, I; Kumar, L; Kycia, R A; Lamont, M A C; Landgraf, J M; Landry, K D; Lauret, J; Lebedev, A; Lednicky, R; Lee, J H; LeVine, M J; Li, C; Li, W; Li, X; Li, X; Li, Y; Li, Z M; Lisa, M A; Liu, F; Ljubicic, T; Llope, W J; Lomnitz, M; Longacre, R S; Luo, X; Ma, G L; Ma, Y G; Madagodagettige Don, D M M D; Mahapatra, D P; Majka, R; Margetis, S; Markert, C; Masui, H; Matis, H S; McDonald, D; McShane, T S; Minaev, N G; Mioduszewski, S; Mohanty, B; Mondal, M M; Morozov, D A; Mustafa, M K; Nandi, B K; Nasim, Md; Nayak, T K; Nelson, J M; Nigmatkulov, G; Nogach, L V; Noh, S Y; Novak, J; Nurushev, S B; Odyniec, G; Ogawa, A; Oh, K; Ohlson, A; Okorokov, V; Oldag, E W; Olvitt, D L; Pachr, M; Page, B S; Pal, S K; Pan, Y X; Pandit, Y; Panebratsev, Y; Pawlak, T; Pawlik, B; Pei, H; Perkins, C; Peryt, W; Pile, P; Planinic, M; Pluta, J; Poljak, N; Porter, J; Poskanzer, A M; Pruthi, N K; Przybycien, M; Pujahari, P R; Putschke, J; Qiu, H; Quintero, A; Ramachandran, S; Raniwala, R; Raniwala, S; Ray, R L; Riley, C K; Ritter, H G; Roberts, J B; Rogachevskiy, O V; Romero, J L; Ross, J F; Roy, A; Ruan, L; Rusnak, J; Rusnakova, O; Sahoo, N R; Sahu, P K; Sakrejda, I; Salur, S; Sandweiss, J; Sangaline, E; Sarkar, A; Schambach, J; Scharenberg, R P; Schmah, A M; Schmidke, W B; Schmitz, N; Seger, J; Seyboth, P; Shah, N; Shahaliev, E; Shanmuganathan, P V; Shao, M; Sharma, B; Shen, W Q; Shi, S S; Shou, Q Y; Sichtermann, E P; Singaraju, R N; Skoby, M J; Smirnov, D; Smirnov, N; Solanki, D; Sorensen, P; Spinka, H M; Srivastava, B; Stanislaus, T D S; Stevens, J R; Stock, R; Strikhanov, M; Stringfellow, B; Sumbera, M; Sun, X; Sun, X M; Sun, Y; Sun, Z; Surrow, B; Svirida, D N; Symons, T J M; Szelezniak, M A; Takahashi, J; Tang, A H; Tang, Z; Tarnowsky, T; Thomas, J H; Timmins, A R; Tlusty, D; Tokarev, M; Trentalange, S; Tribble, R E; Tribedy, P; Trzeciak, B A; Tsai, O D; Turnau, J; Ullrich, T; Underwood, D G; Van Buren, G; van Nieuwenhuizen, G; Vandenbroucke, M; Vanfossen, J A; Varma, R; Vasconcelos, G M S; Vasiliev, A N; Vertesi, R; Videbæk, F; Viyogi, Y P; Vokal, S; Voloshin, S A; Vossen, A; Wada, M; Wang, F; Wang, G; Wang, H; Wang, J S; Wang, X L; Wang, Y; Wang, Y; Webb, G; Webb, J C; Westfall, G D; Wieman, H; Wissink, S W; Witt, R; Wu, Y F; Xiao, Z; Xie, W; Xin, K; Xu, H; Xu, J; Xu, N; Xu, Q H; Xu, Y; Xu, Z; Yan, W; Yang, C; Yang, Y; Yang, Y; Ye, Z; Yepes, P; Yi, L; Yip, K; Yoo, I-K; Yu, N; Zawisza, Y; Zbroszczyk, H; Zha, W; Zhang, J B; Zhang, J L; Zhang, S; Zhang, X P; Zhang, Y; Zhang, Z P; Zhao, F; Zhao, J; Zhong, C; Zhu, X; Zhu, Y H; Zoulkarneeva, Y; Zyzak, M

    2014-08-01

    Local parity-odd domains are theorized to form inside a quark-gluon plasma which has been produced in high-energy heavy-ion collisions. The local parity-odd domains manifest themselves as charge separation along the magnetic field axis via the chiral magnetic effect. The experimental observation of charge separation has previously been reported for heavy-ion collisions at the top RHIC energies. In this Letter, we present the results of the beam-energy dependence of the charge correlations in Au+Au collisions at midrapidity for center-of-mass energies of 7.7, 11.5, 19.6, 27, 39, and 62.4 GeV from the STAR experiment. After background subtraction, the signal gradually reduces with decreased beam energy and tends to vanish by 7.7 GeV. This implies the dominance of hadronic interactions over partonic ones at lower collision energies. PMID:25126911

  11. Continuous rhamnolipid production with integrated product removal by foam fractionation and magnetic separation of immobilized Pseudomonas aeruginosa.

    Science.gov (United States)

    Heyd, M; Franzreb, M; Berensmeier, S

    2011-01-01

    Increasing interest in biological surfactants has led to intensified research directed at more cost-efficient production of biosurfactants, relative to traditional surface-active components based on petrochemical feedstocks. This publication will focus on a new integrated process for continuous rhamnolipid (RL) production. RL was synthesized by Pseudomonas aeruginosa DSM 2874 and was continuously removed in situ by foam fractionation. To prevent loss of the biocatalyst through foaming, bacteria were entrapped in magnetic alginate beads. Immobilizates were retained from the foam by high-gradient magnetic separation and back-flushed in the bioreactor at constant intervals. It was demonstrated that continuous RL production in a 10-L bioreactor over several cycles with intermediate growth periods is feasible. Complete separation of RLs from the production medium with an average enrichment ratio of 15 in the collapsed foam was demonstrated, yielding a final RL amount of 70 g after four production cycles. PMID:21567991

  12. Beam-Energy Dependence of Charge Separation along the Magnetic Field in Au +Au Collisions at RHIC

    Science.gov (United States)

    Adamczyk, L.; Adkins, J. K.; Agakishiev, G.; Aggarwal, M. M.; Ahammed, Z.; Alekseev, I.; Alford, J.; Anson, C. D.; Aparin, A.; Arkhipkin, D.; Aschenauer, E. C.; Averichev, G. S.; Banerjee, A.; Beavis, D. R.; Bellwied, R.; Bhasin, A.; Bhati, A. K.; Bhattarai, P.; Bichsel, H.; Bielcik, J.; Bielcikova, J.; Bland, L. C.; Bordyuzhin, I. G.; Borowski, W.; Bouchet, J.; Brandin, A. V.; Brovko, S. G.; Bültmann, S.; Bunzarov, I.; Burton, T. P.; Butterworth, J.; Caines, H.; Calderón de la Barca Sánchez, M.; Cebra, D.; Cendejas, R.; Cervantes, M. C.; Chaloupka, P.; Chang, Z.; Chattopadhyay, S.; Chen, H. F.; Chen, J. H.; Chen, L.; Cheng, J.; Cherney, M.; Chikanian, A.; Christie, W.; Chwastowski, J.; Codrington, M. J. M.; Contin, G.; Cramer, J. G.; Crawford, H. J.; Cui, X.; Das, S.; Davila Leyva, A.; De Silva, L. C.; Debbe, R. R.; Dedovich, T. G.; Deng, J.; Derevschikov, A. A.; Derradi de Souza, R.; Dhamija, S.; di Ruzza, B.; Didenko, L.; Dilks, C.; Ding, F.; Djawotho, P.; Dong, X.; Drachenberg, J. L.; Draper, J. E.; Du, C. M.; Dunkelberger, L. E.; Dunlop, J. C.; Efimov, L. G.; Engelage, J.; Engle, K. S.; Eppley, G.; Eun, L.; Evdokimov, O.; Eyser, O.; Fatemi, R.; Fazio, S.; Fedorisin, J.; Filip, P.; Finch, E.; Fisyak, Y.; Flores, C. E.; Gagliardi, C. A.; Gangadharan, D. R.; Garand, D.; Geurts, F.; Gibson, A.; Girard, M.; Gliske, S.; Greiner, L.; Grosnick, D.; Gunarathne, D. S.; Guo, Y.; Gupta, A.; Gupta, S.; Guryn, W.; Haag, B.; Hamed, A.; Han, L.-X.; Haque, R.; Harris, J. W.; Heppelmann, S.; Hirsch, A.; Hoffmann, G. W.; Hofman, D. J.; Horvat, S.; Huang, B.; Huang, H. Z.; Huang, X.; Huck, P.; Humanic, T. J.; Igo, G.; Jacobs, W. W.; Jang, H.; Judd, E. G.; Kabana, S.; Kalinkin, D.; Kang, K.; Kauder, K.; Ke, H. W.; Keane, D.; Kechechyan, A.; Kesich, A.; Khan, Z. H.; Kikola, D. P.; Kisel, I.; Kisiel, A.; Koetke, D. D.; Kollegger, T.; Konzer, J.; Koralt, I.; Kotchenda, L.; Kraishan, A. F.; Kravtsov, P.; Krueger, K.; Kulakov, I.; Kumar, L.; Kycia, R. A.; Lamont, M. A. C.; Landgraf, J. M.; Landry, K. D.; Lauret, J.; Lebedev, A.; Lednicky, R.; Lee, J. H.; LeVine, M. J.; Li, C.; Li, W.; Li, X.; Li, X.; Li, Y.; Li, Z. M.; Lisa, M. A.; Liu, F.; Ljubicic, T.; Llope, W. J.; Lomnitz, M.; Longacre, R. S.; Luo, X.; Ma, G. L.; Ma, Y. G.; Madagodagettige Don, D. M. M. D.; Mahapatra, D. P.; Majka, R.; Margetis, S.; Markert, C.; Masui, H.; Matis, H. S.; McDonald, D.; McShane, T. S.; Minaev, N. G.; Mioduszewski, S.; Mohanty, B.; Mondal, M. M.; Morozov, D. A.; Mustafa, M. K.; Nandi, B. K.; Nasim, Md.; Nayak, T. K.; Nelson, J. M.; Nigmatkulov, G.; Nogach, L. V.; Noh, S. Y.; Novak, J.; Nurushev, S. B.; Odyniec, G.; Ogawa, A.; Oh, K.; Ohlson, A.; Okorokov, V.; Oldag, E. W.; Olvitt, D. L.; Pachr, M.; Page, B. S.; Pal, S. K.; Pan, Y. X.; Pandit, Y.; Panebratsev, Y.; Pawlak, T.; Pawlik, B.; Pei, H.; Perkins, C.; Peryt, W.; Pile, P.; Planinic, M.; Pluta, J.; Poljak, N.; Porter, J.; Poskanzer, A. M.; Pruthi, N. K.; Przybycien, M.; Pujahari, P. R.; Putschke, J.; Qiu, H.; Quintero, A.; Ramachandran, S.; Raniwala, R.; Raniwala, S.; Ray, R. L.; Riley, C. K.; Ritter, H. G.; Roberts, J. B.; Rogachevskiy, O. V.; Romero, J. L.; Ross, J. F.; Roy, A.; Ruan, L.; Rusnak, J.; Rusnakova, O.; Sahoo, N. R.; Sahu, P. K.; Sakrejda, I.; Salur, S.; Sandweiss, J.; Sangaline, E.; Sarkar, A.; Schambach, J.; Scharenberg, R. P.; Schmah, A. M.; Schmidke, W. B.; Schmitz, N.; Seger, J.; Seyboth, P.; Shah, N.; Shahaliev, E.; Shanmuganathan, P. V.; Shao, M.; Sharma, B.; Shen, W. Q.; Shi, S. S.; Shou, Q. Y.; Sichtermann, E. P.; Singaraju, R. N.; Skoby, M. J.; Smirnov, D.; Smirnov, N.; Solanki, D.; Sorensen, P.; Spinka, H. M.; Srivastava, B.; Stanislaus, T. D. S.; Stevens, J. R.; Stock, R.; Strikhanov, M.; Stringfellow, B.; Sumbera, M.; Sun, X.; Sun, X. M.; Sun, Y.; Sun, Z.; Surrow, B.; Svirida, D. N.; Symons, T. J. M.; Szelezniak, M. A.; Takahashi, J.; Tang, A. H.; Tang, Z.; Tarnowsky, T.; Thomas, J. H.; Timmins, A. R.; Tlusty, D.; Tokarev, M.; Trentalange, S.; Tribble, R. E.; Tribedy, P.; Trzeciak, B. A.; Tsai, O. D.; Turnau, J.; Ullrich, T.; Underwood, D. G.; Van Buren, G.; van Nieuwenhuizen, G.; Vandenbroucke, M.; Vanfossen, J. A.; Varma, R.; Vasconcelos, G. M. S.; Vasiliev, A. N.; Vertesi, R.; Videbæk, F.; Viyogi, Y. P.; Vokal, S.; Voloshin, S. A.; Vossen, A.; Wada, M.; Wang, F.; Wang, G.; Wang, H.; Wang, J. S.; Wang, X. L.; Wang, Y.; Wang, Y.; Webb, G.; Webb, J. C.; Westfall, G. D.; Wieman, H.; Wissink, S. W.; Witt, R.; Wu, Y. F.; Xiao, Z.; Xie, W.; Xin, K.; Xu, H.; Xu, J.; Xu, N.; Xu, Q. H.; Xu, Y.; Xu, Z.; Yan, W.; Yang, C.; Yang, Y.; Yang, Y.; Ye, Z.; Yepes, P.; Yi, L.; Yip, K.; Yoo, I.-K.; Yu, N.; Zawisza, Y.; Zbroszczyk, H.; Zha, W.; Zhang, J. B.; Zhang, J. L.; Zhang, S.; Zhang, X. P.; Zhang, Y.; Zhang, Z. P.; Zhao, F.; Zhao, J.; Zhong, C.; Zhu, X.; Zhu, Y. H.

    2014-08-01

    Local parity-odd domains are theorized to form inside a quark-gluon plasma which has been produced in high-energy heavy-ion collisions. The local parity-odd domains manifest themselves as charge separation along the magnetic field axis via the chiral magnetic effect. The experimental observation of charge separation has previously been reported for heavy-ion collisions at the top RHIC energies. In this Letter, we present the results of the beam-energy dependence of the charge correlations in Au +Au collisions at midrapidity for center-of-mass energies of 7.7, 11.5, 19.6, 27, 39, and 62.4 GeV from the STAR experiment. After background subtraction, the signal gradually reduces with decreased beam energy and tends to vanish by 7.7 GeV. This implies the dominance of hadronic interactions over partonic ones at lower collision energies.

  13. Polyvinyl-alcohol-based magnetic beads for rapid and efficient separation of specific or unspecific nucleic acid sequences

    International Nuclear Information System (INIS)

    The versatile application of polyvinyl-alcohol-based magnetic M-PVA beads is demonstrated in the separation of genomic DNA, sequence specific nucleic acid purification, and binding of bacteria for subsequent DNA extraction and detection. It is shown that nucleic acids can be obtained in high yield and purity using M-PVA beads, making sample preparation efficient, fast and highly adaptable for automation processes

  14. The Vlasov equation with strong magnetic field and oscillating electric field as a model for isotop resonant separation

    Directory of Open Access Journals (Sweden)

    Emmanuel Frenod

    2002-01-01

    Full Text Available We study the qualitative behavior of solutions to the Vlasov equation with strong external magnetic field and oscillating electric field. This model is relevant to the understanding of isotop resonant separation. We show that the effective equation is a kinetic equation with a memory term. This memory term involves a pseudo-differential operator whose kernel is characterized by an integral equation involving Bessel functions. The kernel is explicitly given in some particular cases.

  15. The Vlasov equation with strong magnetic field and oscillating electric field as a model of isotope resonant separation

    OpenAIRE

    Frenod, Emmanuel; Watbled, Frederique

    2007-01-01

    We study qualitative behavior of the Vlasov equation with strong external magnetic field and oscillating electric field. This model is relevant in order to understand isotop resonant separation. We show that the effective equation is a kinetic equation with a memory term. This memory term involves a pseudo-differential operator whose kernel is characterized by an integral equation involving Bessel functions. In some particular cases, the kernel is explicitly given.

  16. The Vlasov equation with strong magnetic field and oscillating electric field as a model for isotop resonant separation

    OpenAIRE

    Emmanuel Frenod; Frederique Watbled

    2002-01-01

    We study the qualitative behavior of solutions to the Vlasov equation with strong external magnetic field and oscillating electric field. This model is relevant to the understanding of isotop resonant separation. We show that the effective equation is a kinetic equation with a memory term. This memory term involves a pseudo-differential operator whose kernel is characterized by an integral equation involving Bessel functions. The kernel is explicitly given in some particular cases.

  17. Magnetic nanohybrids loaded with bimetal core-shell-shell nanorods for bacteria capture, separation, and near-infrared photothermal treatment.

    Science.gov (United States)

    Hu, Bo; Wang, Ning; Han, Lu; Chen, Ming-Li; Wang, Jian-Hua

    2015-04-20

    A novel antimicrobial nanohybrid based on near-infrared (NIR) photothermal conversion is designed for bacteria capture, separation, and sterilization (killing). Positively charged magnetic reduced graphene oxide with modification by polyethylenimine (rGO-Fe3 O4 -PEI) is prepared and then loaded with core-shell-shell Au-Ag-Au nanorods to construct the nanohybrid rGO-Fe3 O4 -Au-Ag-Au. NIR laser irradiation melts the outer Au shell and exposes the inner Ag shell, which facilitates controlled release of the silver shell. The nanohybrids combine physical photothermal sterilization as a result of the outer Au shell with the antibacterial effect of the inner Ag shell. In addition, the nanohybrid exhibits high heat conductivity because of the rGO and rapid magnetic-separation capability that is attributable to Fe3 O4 . The nanohybrid provides a significant improvement of bactericidal efficiency with respect to bare Au-Ag-Au nanorods and facilitates the isolation of bacteria from sample matrixes. A concentration of 25 ?g mL(-1) of nanohybrid causes 100 % capture and separation of Escherichia coli O157:H7 (1×10(8) cfu mL(-1) ) from an aqueous medium in 10 min. In addition, it causes a 22 °C temperature rise for the surrounding solution under NIR irradiation (785 nm, 50 mW cm(-2) ) for 10 min. With magnetic separation, 30 ?g mL(-1) of nanohybrid results in a 100 % killing rate for E. coli O157:H7 cells. The facile bacteria separation and photothermal sterilization is potentially feasible for environmental and/or clinical treatment. PMID:25754902

  18. Microstructure and magnetic properties of Gd-Hf-Co-Al glassy alloys by liquid-liquid phase separation

    International Nuclear Information System (INIS)

    Phase separated glassy ribbons were prepared in the Gd-Hf-Co-Al system by rapid quenching of the melt. From the Gd55Co25Al20 ternary good glass former, we substitute Gd with Hf by 10, 20, 27.5, 35, 45 and 55 at. %. Due to the strong positive enthalpy of mixing between the principal elements Gd and Hf (?Hmix = +11kJ/mole) a heterogeneous microstructure is formed consisting of two amorphous phases Gd-enriched and Hf-enriched. For the alloys with clearly phase separated microstructure, nano-meter scale (100nm) secondary phase separation is observed in each amorphous phase. In the case of the Gd27.5Hf27.5Co25Al20 alloy, coexistence of two different types of microstructure such as a droplet-like and interconnected structure were observed from the areas having different cooling rate. This microstructure evolution is in good agreement with calculation results by Lattice Boltzmann method. On the other hand, measured magnetic properties show the composition and volume fraction dependence of magnetization and transition temperature (Tc) of Gd-Hf-Co-Al system. The saturation magnetization decreases as a function of Hf contents and can be described by a simple mixture model.

  19. The effect of particle size and colloid stability on the wet high-intensity magnetic separation of uranium from cyanidation residues

    International Nuclear Information System (INIS)

    This report describes an experimental investigation on the magnetic separation of U3O8 from various size fractions of uranium-gold tailings. High recoveries were obtained at high grades, even from the finest fraction (smaller than 25?m), and an increase in magnetic field did not improve the efficiency of separation. The use of theoretical models did not lead to the correct prediction of the limiting particle size recoverable by magnetic separation. It was shown that the presence of coarse fractions enhances the recovery of uranium from a very fine fraction, and that 'piggy-back' magnetic separation plays an important role in the capture of slimes. The results also showed that the use of a dispersant considerably improves the selectivity of the separation

  20. Separation of Microcystin-LR by Cyclodextrin-Functionalized Magnetic Composite of Colloidal Graphene and Porous Silica.

    Science.gov (United States)

    Sinha, Arjyabaran; Jana, Nikhil R

    2015-05-13

    Microcystin-LR belongs to the family of microcystins produced by cyanobacteria and known to be the most toxic of this family. Existence of cyanobacteria in water bodies leads to the contamination of drinking water with microcystin-LR and thus their separation is essential for an advanced water purification system. Here we report functional nanocomposite-based selective separation of microcystin-LR from contaminated water. We have synthesized cyclodextrin-functionalized magnetic composite of colloidal graphene and porous silica where the cyclodextrin component offers host-guest interaction with microcystin-LR and the magnetic component offers easier separation of microcystin-LR from water. High surface area and large extent of chemical functional groups offer high loading (up to 18 wt %) of cyclodextrin with these nanocomposites, and the dispersible form of the nanocomposite offers easier accessibility of cyclodextrin to microcystin-LR. We have shown that microcystin-LR separation efficiency is significantly enhanced after functionalization with cyclodextrin, and among all the tested cyclodextrins, ?-cyclodextrin offers the best performance. We have also found that graphene-based nanocomposite offers better performance over porous silica-based nanocomposite due to better accessibility of cyclodextrins for interaction with microcystin-LR. The proposed graphene-based functional nanocomposite is environment friendly, reusable, and applicable for advanced water purification. PMID:25906257

  1. Synthesis and performance of novel magnetically separable nanospheres of titanium dioxide photocatalyst with egg-like structure

    International Nuclear Information System (INIS)

    A magnetically separable photocatalyst TiO2/SiO2/NiFe2O4 (TSN) nanosphere with egg-like structure was prepared by a unique process that combined a liquid catalytic phase transformation method, reverse micelle technique and chemical precipitation means. The prepared photocatalyst shows high photocatalytic activity for the degradation of methyl orange in water. The magnetic property measurements indicate that the photocatalyst possesses a superparamagnetic nature. It can be separated from water when an external magnetic field is added and redispersed into water solution after the external magnetic field is eliminated. It is one of the promising photocatalysts for wastewater treatment. A transmission electron microscope (TEM) and an x-ray diffractometer (XRD) were used to characterize the structure of the TSN photocatalyst. The results indicate that nickel ferrite core nanoparticles were completely encapsulated into monodisperse silica nanospheres as carrier, and titania nanoparticle aggregates were coated onto the surface of SN nanospheres, forming an imperfect TiO2 shell for photocatalysis. The SiO2 layer between the NiFe2O4 core and the TiO2 shell effectively prevents the injection of charges from TiO2 particles to NiFe2O4, which gives rise to an increase in photocatalytic activity. Moreover, the recycled TSN exhibits good repeatability orecycled TSN exhibits good repeatability of the photocatalytic activity

  2. Correspondence between neutron depolarization and higher order magnetic susceptibility to investigate ferromagnetic clusters in phase separated systems.

    Science.gov (United States)

    Manna, Kaustuv; Samal, D; Bera, A K; Elizabeth, Suja; Yusuf, S M; Kumar, P S Anil

    2014-01-01

    It is a tough task to distinguish a short-range ferromagnetically correlated cluster-glass phase from a canonical spin-glass-like phase in many magnetic oxide systems using conventional magnetometry measurements. As a case study, we investigate the magnetic ground state of La0.85Sr0.15CoO3, which is often debated based on phase separation issues. We report the results of two samples of La0.85Sr0.15CoO3 (S-1 and S-2) prepared under different conditions. Neutron depolarization, higher harmonic ac susceptibility and magnetic relaxation studies were carried out along with conventional magnetometry measurements to differentiate subtle changes at the microscopic level. There is no evidence of ferromagnetic correlation in the sample S-2 attributed to a spin-glass phase, and this is compounded by the lack of existence of a second order component of higher harmonic ac susceptibility and neutron depolarization. A magnetic relaxation experiment at different temperatures complements the spin glass characteristic in S-2. All these signal a sharp variance when we consider the cluster-glass-like phase (phase separated) in S-1, especially when prepared from an improper chemical synthesis process. This shows that the nonlinear ac susceptibility is a viable tool to detect ferromagnetic clusters such as those the neutron depolarization study can reveal. PMID:24275331

  3. Correspondence between neutron depolarization and higher order magnetic susceptibility to investigate ferromagnetic clusters in phase separated systems

    International Nuclear Information System (INIS)

    It is a tough task to distinguish a short-range ferromagnetically correlated cluster-glass phase from a canonical spin-glass-like phase in many magnetic oxide systems using conventional magnetometry measurements. As a case study, we investigate the magnetic ground state of La0.85Sr0.15CoO3, which is often debated based on phase separation issues. We report the results of two samples of La0.85Sr0.15CoO3 (S-1 and S-2) prepared under different conditions. Neutron depolarization, higher harmonic ac susceptibility and magnetic relaxation studies were carried out along with conventional magnetometry measurements to differentiate subtle changes at the microscopic level. There is no evidence of ferromagnetic correlation in the sample S-2 attributed to a spin-glass phase, and this is compounded by the lack of existence of a second order component of higher harmonic ac susceptibility and neutron depolarization. A magnetic relaxation experiment at different temperatures complements the spin glass characteristic in S-2. All these signal a sharp variance when we consider the cluster-glass-like phase (phase separated) in S-1, especially when prepared from an improper chemical synthesis process. This shows that the nonlinear ac susceptibility is a viable tool to detect ferromagnetic clusters such as those the neutron depolarization study can reveal. (paper)

  4. Spin-glass-like state in GdCu: role of phase separation and magnetic frustration

    OpenAIRE

    Bhattacharyya, A.; Giri, S.; Majumdar, S.

    2011-01-01

    We report investigations on the ground state magnetic properties of intermetallic compound GdCu through dc magnetization measurements. GdCu undergoes first order martensitic type structural transition over a wide temperature window of coexisting phases. The high temperature cubic and the low temperature orthorhombic phases have different magnetic character and they show antiferromagnetic and helimagnetic orderings below 145 K and 45 K respectively. We observe clear signature...

  5. Bimodal properties of a patterned magnetic nanostructure: Separation of individual components’ contributions

    Energy Technology Data Exchange (ETDEWEB)

    Sveklo, I. [Faculty of Physics, University of Bia?ystok, ul. Lipowa 41, 15-424 Bia?ystok (Poland); Kupala State University, Ozheshko str. 22, Grodno 230023 (Belarus); Kurant, Z.; Maziewski, A. [Faculty of Physics, University of Bia?ystok, ul. Lipowa 41, 15-424 Bia?ystok (Poland); Sieczkowska, E.; Petroutchik, A.; Baczewski, L.T. [Institute of Physics Polish Academy of Sciences, Al. Lotników 32/46, 02-668 Warszawa (Poland); Wawro, A., E-mail: wawro@ifpan.edu.pl [Institute of Physics Polish Academy of Sciences, Al. Lotników 32/46, 02-668 Warszawa (Poland)

    2013-11-15

    We study the properties of magnetic islands with perpendicular magnetization (dots), hundred nanometres in lateral size, embedded in a magnetic matrix, by magneto-optical method exploiting Kerr effect and magnetic force microscopy. Due to a complex structure the investigated patterned system displays a bimodal character. In order to gain an insight into behaviour of the components we apply a simple approach for decomposition of bimodal hysteresis loops obtained from magneto-optical measurements. The hysteresis loops of subsystems are determined from the field dependent rotation of a plane polarization and ellipticity of a laser beam reflected from the sample surface. Comparison with the adequate reference samples reveals differences in the behaviour of the patterned system resulting from confined size of the dots and their dipole coupling with the matrix. Magnetization reversal mechanisms of the individual components are discussed in details. - Highlights: • Magnetic nanoislands with perpendicular magnetization are studied by MOKE and MFM. • A simple model to extract magnetic properties of the system components is used. • Fitting conditions of the component hysteresis loops are discussed. • Magnetization reversal of the nanoislands and the matrix and their coupling are deduced.

  6. Bimodal properties of a patterned magnetic nanostructure: Separation of individual components’ contributions

    International Nuclear Information System (INIS)

    We study the properties of magnetic islands with perpendicular magnetization (dots), hundred nanometres in lateral size, embedded in a magnetic matrix, by magneto-optical method exploiting Kerr effect and magnetic force microscopy. Due to a complex structure the investigated patterned system displays a bimodal character. In order to gain an insight into behaviour of the components we apply a simple approach for decomposition of bimodal hysteresis loops obtained from magneto-optical measurements. The hysteresis loops of subsystems are determined from the field dependent rotation of a plane polarization and ellipticity of a laser beam reflected from the sample surface. Comparison with the adequate reference samples reveals differences in the behaviour of the patterned system resulting from confined size of the dots and their dipole coupling with the matrix. Magnetization reversal mechanisms of the individual components are discussed in details. - Highlights: • Magnetic nanoislands with perpendicular magnetization are studied by MOKE and MFM. • A simple model to extract magnetic properties of the system components is used. • Fitting conditions of the component hysteresis loops are discussed. • Magnetization reversal of the nanoislands and the matrix and their coupling are deduced

  7. Multifunctional superparamagnetic nanoshells: combining two-photon luminescence imaging, surface-enhanced Raman scattering and magnetic separation.

    Science.gov (United States)

    Jin, Xiulong; Li, Haiyan; Wang, Shanshan; Kong, Ni; Xu, Hong; Fu, Qihua; Gu, Hongchen; Ye, Jian

    2014-11-01

    With the increasing need for multi-purpose analysis in the biomedical field, traditional single diagnosis methods cannot meet the requirements. Therefore new multifunctional technologies and materials for the integration of sample collection, sensing and imaging are in great demand. Core-shell nanoparticles offer a unique platform to combine multifunctions in a single particle. In this work, we have constructed a novel type of core-shell superparamagnetic nanoshell (Fe?O?@SiO?@Au), composed of a Fe?O? cluster core, a thin Au shell and a SiO? layer in between. The obtained multifunctional nanoparticles combine the magnetic properties and plasmonic optical properties effectively, which were well investigated by a number of experimental characterization methods and theoretical simulations. We have demonstrated that Fe?O?@SiO?@Au nanoparticles can be utilized for two-photon luminescence (TPL) imaging, near-infrared surface-enhanced Raman scattering (NIR SERS) and cell collection by magnetic separation. The TPL intensity could be further greatly enhanced through the plasmon coupling effect in the self-assembled nanoparticle chains, which were triggered by an external magnetic field. In addition, Fe?O?@SiO?@Au nanoparticles may have great potential applications such as enhanced magnetic resonance imaging (MRI) and photo-thermotherapy. Successful combination of multifunctions including magnetic response, biosensing and bioimaging in single nanoparticles allows further manipulation, real-time tracking, and intracellular molecule analysis of live cells at a single-cell level. PMID:25329447

  8. Possible magnetic phase separation in Ru-doped La0.67Ca0.33MnO3

    International Nuclear Information System (INIS)

    X-ray diffraction, resistivity, AC susceptibility and magnetization studies on La0.67Ca0.33Mn1-xRuxO3 (0?x3+ and Ru4+. The resistivity of the doped compounds exhibited two features: a broad hump and a relatively sharp peak. While a para- to ferromagnetic transition could be observed for the latter peak, no magnetic signal either in AC susceptibility or in magnetization measurements could be observed for the broad hump. The magnetic moment of Mn per unit cell decreases non-linearly from 3.55 to 3 ?B for the Ru compositions studied. Based on the results of the present studies and existing literature on Mn-site substituted systems, we argue that a magnetic phase separation occurs in the Ru-doped system. While the sharp peak in the resistivity corresponds to Ru4+-enriched regions with ferromagnetic coupling of Ru with the neighboring Mn ions, the broad peak corresponds to Ru3+-rich regions, with antiferromagnetic coupling of Ru with the neighboring Mn ions

  9. Maximizing haematite recovery within a fine and wide particle-size distribution using wet high-intensity magnetic separation

    Scientific Electronic Library Online (English)

    M, Dworzanowski.

    2014-07-01

    Full Text Available The physical beneficiation of iron ore that has a wide particle-size distribution is problematic, regardless of the process applied, whether dense medium separation, gravity concentration, magnetic separation, or flotation. The problem of particle size is further compounded when there is a significa [...] nt -10 µm fraction. Generally the approach to a wide particle-size distribution is to split into narrower size ranges and treat each separately. More often than not the -10 µm fraction is not treated but discarded. This approach results in a more complicated and expensive flow sheet and the loss of any potential value in the -10 µm fraction. Wet high-intensity magnetic separation (WHIMS) bench-scale test work was conducted on a haematite-rich material with a particle size of -200 µm What made this material different was that it contained a 60% -10 µm fraction, hence discarding the -10 µm material was not an option. The objective of the test work was to determine how to maximize the recovery of the haematite across the full particle size range. Given the unusual particle size distribution, it was concluded that WHIMS would be the only practical beneficiation route. The -200 +10 µm and -10 µm fractions were treated separately and together under varying WHIMS conditions. For a given concentrate grade, the mass yield obtained was greater when the total particle-size distribution was treated. The inferred optimum conditions, using the same material, were tested on a pilot-scale WHIMS and similar results were obtained.

  10. Influence of magnetic nanoparticle size on the particle dispersion and phase separation in an ABA triblock copolymer.

    Science.gov (United States)

    Wu, Jinrong; Li, Hui; Wu, Siduo; Huang, Guangsu; Xing, Wang; Tang, Maozhu; Fu, Qiang

    2014-02-27

    Oleic acid modified iron oxide nanoparticles (IONs) with different sizes were synthesized and mixed with styrene-butadiene-styrene block copolymer (SBS) with a lamellar structure. The octadecene segments on the oleic acid molecules have chemical affinity with the polybutadiene (PB) blocks, which makes IONs tend to be selectively confined in the microphase-separated PB domains. However, the dispersion state strongly depends on the ratio of the particle diameter (d) to the lamellar thickness (l) of the PB domains, which further changes the phase separation of SBS. When d/l ?0.5, most of IONs are concentrated in the middle of the PB layers at low particle loading. Upon increasing the particle loading, part of IONs contact each other to form long strings due to their strong magnetic interactions. Away from the strings, IONs are either selectively dispersed in the middle and at the interfaces of the PB domains, or randomly distributed at some regions in which the phase separation of SBS is suppressed. The phase separation of SBS transforms from the lamellar structure to a cylinder structure when the IONs loading is higher than 16.7 wt %. As d is comparable to l, IONs aggregate to form clusters of 100 to 300 nm in size, but within the clusters IONs are still selectively dispersed in the PB domains instead of forming macroscopic phase separation. It is interpreted in terms of the relatively small conformational entropy of the middle blocks of SBS; thus, incorporation of nanoparticles does not lead to much loss of conformational entropy. Although incorporation of IONs with d/l ?1 significantly increases the interfacial curvature and roughness, it has less influence on the phase separation structure of SBS due to the inhomogeneous dispersion. When d is larger than l, IONs are macroscopically separated from the SBS matrix to form clusters of hundreds of nanometers to several micrometers. More interestingly, the phase separation of SBS transforms from the lamellar structure to a two-phase co-continuous structure, probably due to the rearrangement of SBS molecules to cover the clusters with PB segments and the strong magnetic interaction exerting additional force on the SBS matrix during the evaporation of the solvent and the subsequent thermal annealing process. PMID:24479376

  11. Greek “red mud” residue: A study of microwave reductive roasting followed by magnetic separation for a metallic iron recovery process

    International Nuclear Information System (INIS)

    Highlights: • Microwave reduction of a red mud. •Measurement of real and imaginary permittivity of red mud–lignite mixture. •Red mud was subjected to reductive roasting and magnetic separation processes. •The optimum concentrate contains 31.6% iron with a 69.3% metallization degree. •226Ra, 228Ra, 238U, 228Th, 232Th, 40K were detected in the magnetic concentrate. -- Abstract: The present research work is focused on the development of an alternative microwave reductive roasting process of red mud using lignite (30.15 wt.% Cfix), followed by wet magnetic separation, in order to produce a raw material suitable for sponge or cast iron production. The reduction degree of iron was controlled by both the reductive agent content and the microwave heating time. The reduction followed the Fe2O3 ? Fe3O4 ? FeO ? Fe sequence. The dielectric constants [real (??) and imaginary (??) permittivities] of red mud–lignite mixture were determined at 2.45 GHz, in the temperature range of 25–1100 °C. The effect of parameters such as temperature, intensity of reducing conditions, intensity of magnetic field and dispersing agent addition rate on the result of both processes was investigated. The phase's transformations in reduction process with microwave heating were determined by X-ray diffraction analysis (XRD) in combination with thermogravimetric/differential thermal analysis (TGA/DTA). The microstructural and morphological characterization of the produced calcines was carried out by scanning electron microscopy (SEM). At the optimum conditions a magnetic concentrate with total iron concentration of 35.15 and 69.3 wt.% metallization degree was obtained

  12. Purification of equine chorionic gonadotropin (eCG) using magnetic ion exchange adsorbents in combination with high-gradient magnetic separation.

    Science.gov (United States)

    Müller, Christine; Heidenreich, Elena; Franzreb, Matthias; Frankenfeld, Katrin

    2015-01-01

    Current purification of the glycoprotein equine chorionic gonadotropin (eCG) from horse serum includes consecutive precipitation steps beginning with metaphosphoric acid pH fractionation, two ethanol precipitation steps, and dialysis followed by a numerous of fixed-bed chromatography steps up to the specific activity required. A promising procedure for a more economic purification procedure represents a simplified precipitation process requiring only onethird of the solvent, followed by the usage of magnetic ion exchange adsorbents employed together with a newly designed 'rotor-stator' type High Gradient Magnetic Fishing (HGMF) system for large-scale application, currently up to 100 g of magnetic adsorbents. Initially, the separation process design was optimized for binding and elution conditions for the target protein in mL scale. Subsequently, the magnetic filter for particle separation was characterized. Based on these results, a purification process for eCG was designed consisting of (i) pretreatment of the horse serum; (ii) binding of the target protein to magnetic ion exchange adsorbents in a batch reactor; (iii) recovery of loaded functionalized adsorbents from the pretreated solution using HGMF; (iv) washing of loaded adsorbents to remove unbound proteins; (v) elution of the target protein. Finally, the complete HGMF process was automated and conducted with either multiple single-cycles or multicycle operation of four sequential cycles, using batches of pretreated serum of up to 20 L. eCG purification with yields of approximately 53% from single HGMF cycles and up to 80% from multicycle experiments were reached, with purification and concentration factors of around 2,500 and 6.7, respectively. PMID:25393845

  13. Spinel type CoFe oxide porous nanosheets as magnetic adsorbents with fast removal ability and facile separation.

    Science.gov (United States)

    Ge, X; Gu, C D; Wang, X L; Tu, J P

    2015-09-15

    Adsorption is often time consuming due to slow diffusion kinetic. Sizing he adsorbent down might help to accelerate adsorption. For CoFe spinel oxide, a magnetically separable adsorbent, the preparation of nanosheets faces many challenges including phase separation, grain growth and difficulty in preparing two-dimensional materials. In this work, we prepared porous CoFe oxide nanosheet with chemical formula of Co2.698Fe0.302O4 through topochemical transformation of a CoFe precursor, which has a layered double hydroxide (LDH) analogue structure and a large interlayer spacing. The LDH precursor was synthesized from a cheap deep eutectic solvent (DES) system. The calcined Co2.698Fe0.302O4 has small grain size (10-20nm), nanosheet morphology, and porous structure, which contribute to a large specific surface area of 79.5m(2)g(-1). The Co2.698Fe0.302O4 nanosheets show fast removal ability and good adsorption capacity for both organic waste (305mgg(-1) in 5min for Congo red) and toxic heavy metal ion (5.27mgg(-1) in 30min for Cr (VI)). Furthermore, the Co2.698Fe0.302O4 can be separated magnetically. Considering the precursor can be prepared through a fast, simple, surfactant-free and high-yield synthetic strategy, this work should have practical significance in fabricating adsorbents. PMID:26005799

  14. Fingerprints of intrinsic phase separation: magnetically doped two-dimensional electron gas

    OpenAIRE

    Terletska, Hanna; Dobrosavljevic?, Vladimir

    2010-01-01

    In addition to Anderson and Mott localization, intrinsic phase separation has long been advocated as the third fundamental mechanism controlling the doping-driven metal-insulator transitions. In electronic system, where charge neutrality precludes global phase separation, it may lead to various inhomogeneous states and dramaticahttp://arxiv.org/submit/215787/metadata arXiv Submission metadatally affect transport. Here we theoretically predict the precise experimental signatu...

  15. Preliminary magnetic studies of lagoon and stream sediments from Chascomús Area (Argentina)—magnetic parameters as indicators of heavy metal pollution and some results of using an experimental method to separate magnetic phases

    Science.gov (United States)

    Chaparro, Marcos A. E.; Lirio, Juan M.; Nuñez, Héctor; Gogorza, Claudia S. G.; Sinito, Ana M.

    2005-11-01

    Magnetic properties of lagoon and stream sediments from Chascomús area (Buenos Aires Province) and the relevance of various magnetic parameters as giving pollution status are studied in the present work. This work is focussed on magnetic parameters, such as concentration-dependent (magnetic susceptibility, saturation anhysteric and isothermal remanent magnetisation) and feature-dependent parameters (S-ratio, coercivity of remanence, anhysteric susceptibility/magnetic susceptibility-ratio), as pollution indicators. Firstly and most importantly, different magnetic parameters and chemical measurements were correlated in order to investigate their goodness, obtaining the best results for feature-dependent magnetic parameters. Coercivity of remanence correlate very well with chemical variables, showing correlations at high level of significance up to 0.9094, and the anhysteric susceptibility/magnetic susceptibility-ratio also shows very good correlations (up to 0.8376). Some results and advantages of using a new experimental method in order to discriminate hard and soft magnetic phases are also shown. This method uses alternately backfield isothermal remanent magnetisation and alternating field demagnetisation. From the experimental separation, the presence of hard magnetic phases in some samples was confirmed.

  16. Manipulation of magnetic phase separation and orbital occupancy in manganites by strain engineering and electric field

    Science.gov (United States)

    Cui, Bin; Song, Cheng; Pan, Feng; Key Laboratory of Advanced Materials (MOE) Team

    2015-03-01

    The modification of electronic phases in correlated oxides is one of the core issues of condensed matter. We report the reversible control of ferromagnetic phase transition in manganite films by ionic liquid gating, replicating the La1-xSrxMnO3 (LSMO) phase diagram. The formation and annihilation of an insulating and magnetically hard phase in the soft magnetic matrix, which randomly nucleates and grows across the film, is directly observed under different gate voltages (VG) . The realization of reversible metal-insulator transition in colossal magnetoresistance materials can lead to the development of four-state memories. The orbital occupancy and magnetic anisotropy of LSMO films are manipulated by VG in a reversible and quantitative manner. Positive and negative VG increases and reduces the occupancy of the orbital and magnetic anisotropy that were initially favored by strain (irrespective of tensile and compressive), respectively. This finding fills in the blank of electrical manipulation of four degrees of freedom in correlated system.

  17. Magnetoresistance and magnetic susceptibility of phase-separated La-Pr-Ca manganites

    CERN Document Server

    Babushkina, N A; Kugel, K I; Rakhmanov, A L; Gorbenko, O Y; Kaul, A R

    2003-01-01

    Electrical resistivity, magnetoresistance and magnetic susceptibility were measured for ceramic (La sub 1 sub - sub y Pr sub y) sub 0 sub . sub 7 Ca sub 0 sub . sub 3 MnO sub 3 samples (y 0.75 and 1) with different content of sup 1 sup 8 O isotope. All samples were paramagnetic insulators in the high-temperature range. Some of them became ferromagnetic (FM) metals at temperatures below 60-80 K. The high-temperature behaviour of the resistivity, magnetoresistance and magnetic susceptibility was practically identical for all samples in spite of the significant difference in their low-temperature properties. In particular, the magnetoresistance was proportional to the magnetic field squared and decreased approximately as 1/T sup 5 in a wide magnetic field and temperature range. The results were interpreted based on the concept of an inhomogeneous state with pronounced FM correlations in the paramagnetic phase.

  18. Haloing in bimodal magnetic colloids: the role of field induced phase separation

    OpenAIRE

    Magnet, Cécilia; Kuzhir, Pavel; Bossis, Georges; Meunier, Alain; Suloeva, Liudmila; Zubarev, Andrey

    2012-01-01

    If a suspension of magnetic micron-sized and nano-sized particles is subjected to a homogeneous magnetic field, the nanoparticles are attracted to the microparticles and form thick anisotropic halos (clouds) around them. Such clouds can hinder approach of microparticles and result in effective repulsion between them [Lopez-Lopez et al. Soft Matter, 6, 4346 (2010)]. In this paper, we present detailed experimental and theoretical studies of nanoparticle concentration profiles and of the equilib...

  19. Electronic and magnetic phase separation in EuB6. Fluctuation spectroscopy and nonlinear transport

    International Nuclear Information System (INIS)

    The main topics of this thesis are electrical, stationary, and time-resolved transport measurements on EuB6 as well as the further development of measuring methods and analysis procedures of the fluctuation spectroscopy. The first part of this thesis was dedicated to the further development of the already known measuring methods under application of a fast data-acquisition card. The second part deals with the electrical transport properties of EuB6 and the understanding of the coupling between charge and magnetic degrees of freedom. By means of resistance and nonlinear-transport measurements as well as fluctuation spectroscopy hypotheses of other scientists were systematically verified as well as new knowledge obtained. The magnetoresistance was studied as function of the temperature in small external magnetic fields between 1 mT and 700 mT. Measurements of the third harmonic resistance as function of the temperature show maxima at TMI and TC. Electrical-resistance fluctuations were measured without external magnetic field between 5 and 100 K as well in presence of a magnetic field between 18 K and 32 K. At constant temperature measurements of the spectral power density in external magnetic fields were performed in the temperature range from 18 K to 32 K. Highly resolving measurements of the thermal expansion coefficient showed a very strong coupling of the magnetic (polaronic) degrees of freedom to the crystal lattice.

  20. X-ray photoelectron spectroscopy and nuclear magnetic resonance as complementary probes of pseudogaps and spin-charge separation

    Energy Technology Data Exchange (ETDEWEB)

    Shannon, N. [Department of Physics, University of Warwick, Coventry CV4 7AL (United Kingdom)

    2000-08-07

    The possibility that strongly correlated many-electron systems may exhibit spin-charge separation has generated great excitement, particularly in the light of recent experiments on low-dimensional conductors and high-temperature superconductors. However, finding experimental support for this hypothesis has been made difficult by the fact that most commonly used probes couple simultaneously to spin and charge excitations. We argue that core-hole photoemission (XPS)/nuclear magnetic resonance (NMR) couple independently and in exactly comparable ways to the local charge/spin susceptibilities of the system being measured. The explicit comparison of XPS and NMR data, particularly for systems which exhibit a pseudogap, may therefore yield fresh evidence for the existence (or non-existence) of spin-charge separation. Application of these ideas to the normal state of high-temperature superconductors is discussed, and the application is further illustrated in some detail for quasi-one-dimensional systems with charge-density waves. (author)

  1. Superconductivity, metastability and magnetic field induced phase separation in the atomic limit of the Penson-Kolb-Hubbard model

    CERN Document Server

    Kapcia, Konrad Jerzy

    2014-01-01

    We present the analysis of paramagnetic effects of magnetic field ($B$) (Zeeman term) in the zero-bandwidth limit of the extended Hubbard model for arbitrary chemical potential $\\mu$ and electron density $n$. The effective Hamiltonian considered consists of the on-site interaction $U$ and the intersite charge exchange term $I$, determining the hopping of electron pairs between nearest-neighbour sites. The model has been analyzed within the variational approach, which treats the on-site interaction term exactly and the intersite interactions within the mean-field approximation (rigorous in the limit of infinite dimensions $d\\rightarrow+\\infty$). In this report we focus on metastable phases as well as phase separated (PS) states involving superconducting (SS) and nonordered (NO) phases and determine their ranges of occurrence for $U/I_0=1.05$ ($I_0=zI$) in the presence of magnetic field $B\

  2. Separation and enrichment of six indicator polychlorinated biphenyls from real waters using a novel magnetic multiwalled carbon nanotube composite absorbent.

    Science.gov (United States)

    Zhang, Jiabin; Gan, Ning; Pan, Muyun; Lin, Saichai; Cao, Yuting; Wu, Dazhen; Long, Nengbing

    2015-03-01

    A novel and effective magnetic multiwalled carbon nanotube composite for the separation and enrichment of polychlorinated biphenyls was developed. Fe3 O4 @SiO2 core-shell structured nanoparticles were first synthesized, then the poly(sodium 4-styrenesulfonate) was laid on its surface to prepare the polyanionic magnetic nanoparticles. The above materials were then grafted with polycationic multiwalled carbon nanotubes, which were modified by polydiallyl dimethyl ammonium chloride through the layer-by-layer self-assembly approach. Its performance was tested by magnetic solid-phase extraction and gas chromatography with mass spectrometry for the determination of six kinds of indicator polychlorinated biphenyls in water samples. Under optimal conditions, the spiked recoveries of several real samples for six kinds of polychlorinated biphenyls (PCB28, PCB52, PCB101, PCB138, PCB153, PCB180) were in the range of 73.4-99.5% with relative standard deviations varying from 1.5 to 8.4%. All target compounds showed good linearities in the tested range with correlation coefficients higher than 0.9993. The limits of quantification for six kinds of indicator polychlorinated biphenyls were between 0.018 and 0.039 ng/mL. The proposed method was successfully applied to analyze polychlorinated biphenyls in real water samples. Satisfactory results were obtained using the effective magnetic absorbent. PMID:25556922

  3. Rapid purification and characterization of angiotensin converting enzyme inhibitory peptides from lizard fish protein hydrolysates with magnetic affinity separation.

    Science.gov (United States)

    Lan, Xiongdiao; Liao, Dankui; Wu, Shanguang; Wang, Feng; Sun, Jianhua; Tong, Zhangfa

    2015-09-01

    In this study, angiotensin converting enzyme (ACE) inhibitory peptides from lizard fish protein hydrolysate with neutral protease were purified through magnetic affinity separation. Magnetic agarose microsphere was prepared by reverse-phase microemulsion method, and its surface was modified with epoxy groups to immobilize ACE as a magnetic affinity medium (MAM-ACE) and then mixed with lizard fish ultrafiltration hydrolysate (<5kDa). The MAM-ACE was recovered by a magnet. The bound peptides were released by 1M NaCl and further purified by reverse-phase high-performance liquid chromatography. The amino acid sequence of the peptide with the highest ACE inhibitory activity was identified as Gly-Met-Lys-Cys-Ala-Phe, and its IC50 was 45.7±1.1?M. The result indicates that MAM-ACE is a faster and more efficient method for purifying micro-bioactive peptides from food protein complex mixtures compared with ion exchange and gel chromatography. PMID:25842319

  4. Magnetically separable Cu2O/chitosan-Fe3O4 nanocomposites: Preparation, characterization and visible-light photocatalytic performance

    Science.gov (United States)

    Cao, Chunhua; Xiao, Ling; Chen, Chunhua; Cao, Qihua

    2015-04-01

    A novel magnetically-separable visible-light-induced photocatalyst, Cu2O/chitosan-Fe3O4 nanocomposite (Cu2O/CS-Fe3O4 NC), was prepared via a facile one-step precipitation-reduction process by using magnetic chitosan chelating copper ions as precursor. The structure and properties of Cu2O/CS-Fe3O4 NCs were characterized by XRD, FT-IR, SEM, HRTEM, SAED, EDS, BET, VSM, XPS and UV-vis/DRS. The photocatalytic activity of Cu2O/CS-Fe3O4 NCs was evaluated by decolorization of reactive brilliant red X-3B (X-3B) under visible light irradiation. The characterization results indicated that Cu2O/CS-Fe3O4 NCs exhibited relatively large specific surface areas and special dimodal pore structure because Cu2O was wrapped in chitosan matrix embedded with Fe3O4 nanoparticles. The tight combination of magnetic Fe3O4 and semiconductor Cu2O through chitosan made the nanocomposites show good superparamagnetism and photocatalytic activity. It was found that X-3B could be decolorized more efficiently in acidic media than in neutral or alkaline media. The decolorization of X-3B was ascribed to the synergistic effect of photocatalysis and adsorption. Cu2O/CS-Fe3O4 NCs could be easily separated from the solution by an external magnet, and the decolorization rates of X-3B were still above 87% after five reaction cycles, indicating that Cu2O/CS-Fe3O4 NCs had excellent reusability and stability.

  5. Magnetic BaFe12O19 nanofiber filter for effective separation of Fe3O4 nanoparticles and removal of arsenic

    International Nuclear Information System (INIS)

    Magnetic nanoparticles are promising in applications where magnetic separation is intended, although material losses via leaching mechanisms are often inevitable. Magnetic separations with widely available permanent magnets can effectively trap particles, leading to a complete removal of used or waste particles. In this report, we first demonstrate the synthesis of the thinnest (112.7 ± 16.4 nm) and most magnetic (71.96 emu g?1) barium hexaferrite (BaFe12O19, BHF—fridge magnet) via an organic solvent-free electrospinning procedure. When the fibers are then packed into a column, they clearly remove 12 nm magnetite (Fe3O4) nanoparticles quantitatively. The same BHF cartridge also removes more than 99.9 % As-treated magnetite nanoparticles at capacities up to 70 times of its weight. As a result, one liter of 150 ?g L?1 As-contaminated water can be purified rapidly at a material cost of less than 2 US cents

  6. The GSI projectile fragment separator (FRS): a versatile magnetic system for relativistic heavy ions

    International Nuclear Information System (INIS)

    The projectile fragment separator FRS designed for research and applied studies with relativistic heavy ions was installed at GSI as a part of the new high-energy SIS/ESR accelerator facility. This high-resolution forward spectrometer has been successfully used in first atomic and nuclear physics experiments using neon, argon, krypton, xenon, and gold beams in the energy range from 500 to 2000 MeV/u. For the first time relativistic xenon and gold fragments have been isotopically separated. In this contribution we describe first experiments characterizing the performance of the spectrometer. (orig.)

  7. The GSI projectile fragment separator (FRS) - a versatile magnetic system for relativistic heavy ions

    Energy Technology Data Exchange (ETDEWEB)

    Geissel, H.; Armbruster, P.; Behr, K.H.; Bruenle, A.; Burkard, K.; Chen, M.; Folger, H.; Franczak, B.; Keller, H.; Klepper, O.; Langenbeck, B.; Nickel, F.; Pfeng, E.; Pfuetzner, M.; Roeckl, E.; Rykaczewski, K.; Schall, I.; Schardt, D.; Scheidenberger, C.; Schmidt, K.H.; Schroeter, A.; Schwab, T.; Suemmerer, K.; Weber, M.; Muenzenberg, G. (Gesellschaft fuer Schwerionenforschung mbH, Darmstadt (Germany)); Brohm, T.; Clerc,

    1991-09-01

    The projectile fragment separator FRS designed for research and applied studies with relativistic heavy ions was installed at GSI as a part of the new high-energy SIS/ESR accelerator facility. This high-resolution forward spectrometer has been successfully used in first atomic and nuclear physics experiments using neon, argon, krypton, xenon, and gold beams in the energy range from 500 to 2000 MeV/u. For the first time relativistic xenon and gold fragments have been isotopically separated. In this contribution we describe first experiments characterizing the performance of this spectrometer. (orig.).

  8. The GSI projectile fragment separator (FRS): a versatile magnetic system for relativistic heavy ions

    Energy Technology Data Exchange (ETDEWEB)

    Geissel, H.; Armbruster, P.; Behr, K.H.; Bruenle, A.; Burkard, K.; Chen, M.; Folger, H.; Franczak, B.; Keller, H.; Klepper, O.; Langenbeck, B.; Nickel, F.; Pfeng, E.; Pfuetzner, M.; Roeckl, E.; Rykaczewski, K.; Schall, I.; Schardt, D.; Scheidenberger, C.; Schmidt, K.H.; Schroeter, A.; Schwab, T.; Suemmerer, K.; Weber, M.; Muenzenberg, G. (Gesellschaft fuer Schwerionenforschung mbH, Darmstadt (Germany)); Brohm, T.; Clerc, H.G.; Fauerbach, M.; Gaimard, J.J.; Grewe, A.; Hanelt, E.; Knoedler, B.; Steiner, M.; Voss, B.; Weckenmann, J.; Ziegler, C. (TH Darmstadt (Germany). Inst. fuer Kernphysik); Magel, A.; Wollnik, H. (Giessen Univ. (Germany)); Dufour, J.P. (CEN, 33 - Bordeaux (France)); Fujita, Y. (Osaka Univ., Toyonaka (Japan). Coll. of General Education); Vieira, D.J. (Los Alamos National Lab., NM (United States)); Sherrill, B. (NSCL, East Lansing, MI (United States))

    1992-08-01

    The projectile fragment separator FRS designed for research and applied studies with relativistic heavy ions was installed at GSI as a part of the new high-energy SIS/ESR accelerator facility. This high-resolution forward spectrometer has been successfully used in first atomic and nuclear physics experiments using neon, argon, krypton, xenon, and gold beams in the energy range from 500 to 2000 MeV/u. For the first time relativistic xenon and gold fragments have been isotopically separated. In this contribution we describe first experiments characterizing the performance of the spectrometer. (orig.).

  9. The GSI projectile fragment separator (FRS) - a versatile magnetic system for relativistic heavy ions

    International Nuclear Information System (INIS)

    The projectile fragment separator FRS designed for research and applied studies with relativistic heavy ions was installed at GSI as a part of the new high-energy SIS/ESR accelerator facility. This high-resolution forward spectrometer has been successfully used in first atomic and nuclear physics experiments using neon, argon, krypton, xenon, and gold beams in the energy range from 500 to 2000 MeV/u. For the first time relativistic xenon and gold fragments have been isotopically separated. In this contribution we describe first experiments characterizing the performance of this spectrometer. (orig.)

  10. Magnetic phase separation in EuB6 detected by muon spin rotation

    OpenAIRE

    Brooks, Ml; Lancaster, T.; Blundell, Sj; Hayes, W.; Pratt, Fl; Fisk, Z.

    2004-01-01

    We report results of the first muon-spin rotation measurements performed on the low carrier density ferromagnet EuB$_6$. The ferromagnetic state is reached via two magnetic transitions at $T_{\\rm m}=16.5$ K and $T_{\\rm c}=12.6$ K. Two distinct components are resolved in the muon data, one oscillatory and one non-oscillatory, which arise from different types of magnetic environment, and we have followed the temperature dependence of these components in detail. These results p...

  11. Electrostatic separation of ions in a bucket source with magnetic filter

    International Nuclear Information System (INIS)

    We consider how ions with different temperatures may be selectively filtered by an electrostatic barrier which can exist in a magnetic multipole (Bucket) source equipped with a magnetic filter. The H+ ions have a greater temperature than the H2+ and H3+ species and so can cross the electrostatic barrier with less sttenuation than the molecular species. We suggest that low temperature impurity ions may also become trapped in the rear chamber of the source, thus leading to an improvement in source performance

  12. Chip-based magnetic separation technique for simplification of peptide mapping.

    Czech Academy of Sciences Publication Activity Database

    Korecká, L.; K?enková, Jana; Minc, N.; Viovy, J.-L.; Bílková, Z.

    Amsterdam : HPCE´2006 Foundation, 2006 - (Rozing, G.; Rozing, M.). s. 300 ISBN 90-9020408-3. [MSB´2006. International Symposium on Microscale Bioseparations /20./. 22.01.2006-26.01.2006, Amsterdam] R&D Projects: GA ?R GA203/05/0241; GA ?R GA203/05/2106 Keywords : Chip * miniaturization * affinity reactor Subject RIV: CB - Analytical Chemistry, Separation

  13. Separation and purification of hen egg white lysozyme using magnetic particles.

    Czech Academy of Sciences Publication Activity Database

    Šafa?íková, Miroslava; Mad?rová, Zde?ka; Šafa?ík, Ivo

    Patras : University of Patras, 2006, s. 205. [International Congress on Bioprocesses in Food Industries. Patras (GR), 18.06.2006-21.06.2006] R&D Projects: GA MŠk(CZ) 1P05OC053 Institutional research plan: CEZ:AV0Z60870520 Keywords : lysozyme * magnetic particles Subject RIV: EI - Biotechnology ; Bionics

  14. Magnetic IDA-modified hydrophilic methacrylate-based polymer microspheres for IMAC protein separation.

    Czech Academy of Sciences Publication Activity Database

    P?ikryl, P.; Horák, Daniel; Tichá, M.; Ku?erová, Z.

    2006-01-01

    Ro?. 29, ?. 16 (2006), s. 2541-2549. ISSN 1615-9306 R&D Projects: GA ?R GA203/05/0241 Institutional research plan: CEZ:AV0Z40500505 Keywords : human IgG * hydrophilic magnetic microspheres * iminodiacetic acid Subject RIV: CD - Macromolecular Chemistry Impact factor: 2.535, year: 2006

  15. The application of high gradient magnetic separation to the treatment of radioactive waste

    International Nuclear Information System (INIS)

    Activated carbon, incorporating a magnetic seeding agent e.g. iron or iron oxide, used to study adsorption of copper, hydrogen, hydroxide, carbonate, cobalt and strontium ions and protein hydrolysate, glucose and bacteria in relation to treatment of radioactive effluents. Up to 98% of particles could be efficiently removed using pulsed flow equipment. (U.K.)

  16. Magnetic ovalbumin and egg white aggregates as affinity adsorbents for lectins separation.

    Czech Academy of Sciences Publication Activity Database

    Mad?rová, Zde?ka; Šafa?íková, Miroslava; Šafa?ík, Ivo

    2008-01-01

    Ro?. 40, - (2008), s. 542-545. ISSN 1369-703X R&D Projects: GA MŠk OC 157; GA MPO 2A-1TP1/094 Institutional research plan: CEZ:AV0Z60870520 Keywords : egg white * lectins * magnetic protein aggregates Subject RIV: EI - Biotechnology ; Bionics Impact factor: 1.889, year: 2008

  17. A study on the purification of primary coolant in a nuclear power plant using a magnetic filter - electrodeionization hybrid separation system

    International Nuclear Information System (INIS)

    A study on the purification of primary coolant system in a nuclear power plant is carried out using magnetic filter - electrodeionization hybrid separation process. Magnetic filter system with 3000 Gauss permanent manget is used for the removal of CRUD (Chalk River Unidentified Deposit) and electrodeionization for ionic nuclide species. The removal and transport mechanism of nickel ion in an electrodeionization system is explained. The developed magnetic filter - electrodeionization hybrid separation process showed high removal rate over 98 %. The results suggested the applicable possibility for the purification of primary coolant system in a nuclear power plant

  18. Fe3O4@graphene oxide composite: A magnetically separable and efficient catalyst for the reduction of nitroarenes

    International Nuclear Information System (INIS)

    Highlights: ? The Fe3O4@GO composite was prepared by a facile co-precipitation method. ? Fe3O4 nanoparticles are well distributed on GO nanosheets. ? Fe3O4@GO was for the first time explored as a catalyst to reduce nitroarenes. ? Fe3O4@GO exhibits higher catalytic activity. ? The composite catalyst is easily recycled due to its magnetic separability. - Abstract: We reported a facile co-precipitation method to prepare a highly active Fe3O4@graphene oxide (Fe3O4@GO) composite catalyst, which was fully characterized by means of X-ray diffraction (XRD), Fourier transformed infrared (FTIR) spectroscopy, transmission electron microscopy (TEM) and N2 adsorption–desorption measurements. The results demonstrated that the Fe3O4 nanoparticles (Fe3O4 NPs) with a small diameter of around 12 nm were densely and evenly deposited on the graphene oxide (GO) sheets. The as-prepared Fe3O4@GO composite was explored as a catalyst to reduce a series of nitroarenes for the first time, which exhibited a great activity with a turnover frequency (TOF) of 3.63 min?1, forty five times that of the commercial Fe3O4 NPs. The dosages of catalyst and hydrazine hydrate are both less than those reported. Furthermore, the composite catalyst can be easily recovered due to its magnetic separability and high stability

  19. Cyclodextrin-induced lipid lateral separation in DMPC membranes: (2)H nuclear magnetic resonance study.

    OpenAIRE

    Roux, Michel; Auzely-Velty, Rachel; Djedaini-Pilard, Florence; Perly, Bruno

    2002-01-01

    Cholesteryl cyclodextrins, obtained by grafting a cholesterol moiety on the oligosaccharide core, combine the size selectivity of the cyclodextrin cavity with the carrier properties of model membrane systems such as micelles or liposomes. The cholesteryl cyclodextrins were incorporated as guests in chain perdeuterated dimyristoyl phosphatidylcholine (DMPC-d54) membranes. The deuterium nuclear magnetic resonance (NMR) spectra obtained with the A form of cholesteryl-beta-cyclodextrin (beta CC(A...

  20. PadéFroissart exact signal-noise separation in nuclear magnetic resonance spectroscopy

    OpenAIRE

    Belkic?, Dz?evad; Belkic?, Karen

    2011-01-01

    Abstract Nuclear magnetic resonance spectroscopy is one of the key methods for studying the structure of matter on vastly different levels (sub-nuclear, nuclear, atomic, molecular, cellular , etc). Its overall success critically depends upon reliable mathematical analysis and interpretation of the studied data. This is especially aided by parametric signal processing with the ensuing data quantification, which can yield the abundance or concentrations of the constituents in the examined ma...

  1. CALCULATING SEPARATE MAGNETIC FREE ENERGY ESTIMATES FOR ACTIVE REGIONS PRODUCING MULTIPLE FLARES: NOAA AR11158

    International Nuclear Information System (INIS)

    It is well known that photospheric flux emergence is an important process for stressing coronal fields and storing magnetic free energy, which may then be released during a flare. The Helioseismic and Magnetic Imager (HMI) on board the Solar Dynamics Observatory (SDO) captured the entire emergence of NOAA AR 11158. This region emerged as two distinct bipoles, possibly connected underneath the photosphere, yet characterized by different photospheric field evolutions and fluxes. The combined active region complex produced 15 GOES C-class, two M-class, and the X2.2 Valentine's Day Flare during the four days after initial emergence on 2011 February 12. The M and X class flares are of particular interest because they are nonhomologous, involving different subregions of the active region. We use a Magnetic Charge Topology together with the Minimum Current Corona model of the coronal field to model field evolution of the complex. Combining this with observations of flare ribbons in the 1600 Å channel of the Atmospheric Imaging Assembly on board SDO, we propose a minimization algorithm for estimating the amount of reconnected flux and resulting drop in magnetic free energy during a flare. For the M6.6, M2.2, and X2.2 flares, we find a flux exchange of 4.2 × 1020 Mx, 2.0 × 1020 Mx, and 21.0 × 1020 Mx, respectively, resulting in free energy drops of 3.89 × 1030 erg, 2.62 × 1030 erg, and 1.68 × 1032 erg. and 1.68 × 1032 erg.

  2. ? SR study of real space magnetic phase separation in Mn3O4

    Science.gov (United States)

    Zakjevskii, Alexander; Thaler, Alexander; Reig-I-Plessis, Dalmau; Brodsky, Isaac; Gim, Yewon; Aczel, Adam; Cooper, S. Lance; MacDougall, Gregory

    2015-03-01

    The material Mn3O4 is a magnetically frustrated spinel which exhibits three distinct magnetic transitions below 42 K. Recent work has shown that the lowest of these is accompanied by an orthorhombic structural distortion, implying strong magneto-elastic coupling. Magnetic force microscopy (MFM) measurements indicate a substantial region of phase coexistence below this transition, with domain walls that order on the mesoscale. It is further suggested that a tradeoff in ordered volume with field may play a role in the recent quantum phase transition reported in this material. To follow up on these ideas, we have performed a series of zero- and transverse-field muon spin rotation measurements on single-crystal Mn3O4. The zero-field data clearly show the co-existence of ordered and disorder volumes, consistent with MFM results. Here we report these data, and further attempts to vary the ordered volume with applied field. We will discuss both zero- and transverse-field results within the context of the current understanding of the material. This material is based upon work supported by the U.S. Department of Energy, Office of Science, Office of Basic Energy Sciences, under Award Number DE-FG02-07ER46453.

  3. Calculating Separate Magnetic Free Energy Estimates for Active Regions Producing Multiple Flares: NOAA AR11158

    CERN Document Server

    Tarr, Lucas A; Millhouse, Margaret

    2013-01-01

    It is well known that photospheric flux emergence is an important process for stressing coronal fields and storing magnetic free energy, which may then be released during a flare. The \\emph{Helioseismic and Magnetic Imager} (HMI) onboard the \\emph{Solar Dynamics Observatory} (SDO) captured the entire emergence of NOAA AR 11158. This region emerged as two distinct bipoles, possibly connected underneath the photosphere, yet characterized by different photospheric field evolutions and fluxes. The combined active region complex produced 15 GOES C--class, 2 M--class, and the X2.2 Valentine's Day Flare during the four days after initial emergence on February 12th, 2011. The M and X class flares are of particular interest because they are nonhomologous, involving different subregions of the active region. We use a Magnetic Charge Topology together with the Minimum Current Corona model of the coronal field to model field evolution of the complex. Combining this with observations of flare ribbons in the 1600\\AA\\ chann...

  4. Hour-glass magnetic excitations induced by nanoscopic phase separation in cobalt oxides La$_{2-x}$Sr$_x$CoO$_4$

    CERN Document Server

    Drees, Y; Ricci, A; Rotter, M; Schmidt, W; Lamago, D; Sobolev, O; Rütt, U; Gutowski, O; Sprung, M; Piovano, A; Castellan, J P; Komarek, A C

    2015-01-01

    The magnetic excitations in the cuprate superconductors might be essential for an understanding of high-temperature superconductivity. In these cuprate superconductors the magnetic excitation spectrum resembles an hour-glass and certain resonant magnetic excitations within are believed to be connected to the pairing mechanism which is corroborated by the observation of a universal linear scaling of superconducting gap and magnetic resonance energy. So far, charge stripes are widely believed to be involved in the physics of hour-glass spectra. Here we study an isostructural cobaltate that also exhibits an hour-glass magnetic spectrum. Instead of the expected charge stripe order we observe nano phase separation and unravel a microscopically split origin of hour-glass spectra on the nano scale pointing to a connection between the magnetic resonance peak and the spin gap originating in islands of the antiferromagnetic parent insulator. Our findings open new ways to theories of magnetic excitations and superconduc...

  5. Design of Countercurrent Separation of Ginkgo biloba Terpene Lactones by Nuclear Magnetic Resonance

    Science.gov (United States)

    Qiu, Feng; Friesen, Brent J.; McAlpine, James B.; Pauli, Guido F.

    2012-01-01

    Terpene lactones such as bilobalide, ginkgolides A, B, C, and J are major bioactive compounds of Ginkgo biloba L. Purification of these compounds is tedious due to their similar chemical properties. For the purpose of developing an effective and efficient method for both analytical and preparative separation of terpene lactones in G. biloba, an innovative orthogonality-enhanced high-speed countercurrent chromatography (HSCCC) method was established. Taking advantage of quantitative 1H NMR (qHNMR) methodology, partition coefficients (K) of individual terpene lactones were calculated directly from crude G. biloba leaf extract, using their H-12 signals as distinguishing feature. The partitioning experiment assisted the design of a two dimensional (2D) HSCCC procedure using a pair of orthogonal HSCCC solvent systems (SSs), ChMWat +4 and HEMSoWat +3/0.05%. It was surprising that the resolution of ginkgolides A and B was improved by 25% in the HEMWat +3 SS modified with 0.5% DMSO. Consequently, all five terpene lactones could be well separated with qHNMR purity > 95% from G. biloba leaf extract. The separation was further evaluated by offline qHNMR analysis of HSCCC fractions associated with Gaussian curve fitting. The results showed less than 2% error in HSCCC retention predicted from the partitioning experiment. This compelling consistency demonstrates that qHNMR-derived K determination (“K-by-NMR”) can be used to predict CCC fractionation and target purification of analytes from complex mixtures. Furthermore, Gaussian curve fitting enabled an accurate prediction of less than 2% impurity in the CCC fraction, which demonstrates its potential as a powerful tool to study the presence of minor constituents, especially when they are beyond the detection limit of conventional spectroscopic detectors. PMID:22579361

  6. Identification of new astatine isotopes using the gas-filled magnetic separator, Sassy

    International Nuclear Information System (INIS)

    A He-filled on-line separator system was built at the SuperHILAC and used to study the fusion products in the reaction 56Fe + 141Pr. The new neutron-deficient isotopes 194At and 195At were produced in this bombardment as three- and two-neutron-out products, respectively, and were identified by the ?-? time-correlation technique. The measured ? energies and half lives are 7.20 +/- 0.02 MeV and 180 +/- 80 msec for 194At, and 7.12 +/- 0.02 MeV and 200 +/- 100 msec for 195At

  7. Application of magnetite hexacyanoferrate composites in magnetically assisted chemical separation of cesium

    International Nuclear Information System (INIS)

    Potassium nickel hexacyanoferrate composite with magnetite finds application in the recovery of cesium from low-level liquid waste using magnetic assistance. The apparent sorption capability of hexacyanoferrate-magnetite composite and potassium nickel(II) hexacyanoferrate(II) matched indicating no loss in sorption capability as a consequence of coating to nanoscale magnetite substrate. Selectivity for cesium in a broad pH range, selectivity in the presence of high concentration of sodium nitrate, and fast exchange kinetics are additional features of the nanocomposites. (author)

  8. Mass magnetophoretic experiment applied to the separation of biocompatible magnetic nanoparticles with potential for magnetohyperthermia

    International Nuclear Information System (INIS)

    A mass magnetophoretic experiment was developed to segregate nanoparticles according to their diameter and size dispersion. The samples were synthesized by the coprecipitation method and characterized using x-ray diffraction, high-resolution transmission electron microscopy and vibrating sample magnetometry. The mean diameter (standard deviation) showed a decrease of nanoparticle size (size dispersion) in the surface of the magnetic fluid sample submitted to the magnetophoretic experiment. Those effects were monitored by time-dependent apparent mass variation data, which could be important for scale-up applications. Magnetohyperthemia experiments were also performed, confirming our findings. (paper)

  9. Preparation of magnetic carbon nanotubes for separation of pyrethroids from tea samples

    International Nuclear Information System (INIS)

    Magnetic carbon nanotubes (MCNTs) have been synthesized by chemical deposition of Fe3O4 nanoparticles onto carbon nanotubes. They were characterized by Fourier transform infrared spectroscopy, scanning electron microscope, X-ray diffraction and physical property measurement system. The MCNTs were used as the sorbents for the extraction of pyrethroids including beta-cyfluthrin, cyhalothrin and cyphenothrin from tea samples. The extraction conditions, such as the amount of magnetic sorbent, shaking time and rate, washing and eluting solution have been fully investigated. The analytes desorbed from MCNTs were determined by HPLC with UV detection. Under the optimal conditions, the linearity of the method is in the range of 0.05-25 ?g g-1. The limits of detection of the three pyrethroids are 0.017, 0.010 and 0.018 ?g g-1, respectively. The relative standard deviations of within- and between-day range from 3.5 % to 6.4 %, and from 4.5 % to 29 7.3 %, respectively. In all three spiked levels (0.05, 0.5 and 5 ?g g-1), the recoveries of pyrethroids are in the range of 82.2 %-94.4 %. This method is much faster and more effective than traditional methods, and it is promising for the analysis of pesticides residues. (author)

  10. Structural analysis of the phase separation in magnetic semiconductor (Zn, Cr)Te

    International Nuclear Information System (INIS)

    We have studied the structural properties of the phase separation in Zn1-xCrxTe films grown by MBE with a relatively high Cr composition x?0.2. In the combined analyses using TEM and EELS, it has been revealed that the Cr-aggregated regions are composed of precipitates of the hexagonal structure, which are formed in a particular crystallographic relation with the zinc-blende (ZB) structure of the matrix that the c-plane of the hexagonal structure nearly parallel to the (1 1 1) plane of the ZB structure. In the XRD measurements, the diffraction from the hexagonal precipitates has been detected in the ?-scan. From the measurements on the series of films grown at different temperatures, it has been suggested the hexagonal precipitates were formed in a larger quantity with the increase in growth temperature.

  11. Structural analysis of the phase separation in magnetic semiconductor (Zn, Cr)Te

    Energy Technology Data Exchange (ETDEWEB)

    Kobayashi, Hiroaki; Nishio, Yotaro; Kanazawa, Ken [Institute of Materials Science, University of Tsukuba, 1-1-1 Tennoudai, Tsukuba, 305-8573 (Japan); Kuroda, Shinji, E-mail: kuroda@ims.tsukuba.ac.jp [Institute of Materials Science, University of Tsukuba, 1-1-1 Tennoudai, Tsukuba, 305-8573 (Japan); Mitome, Masanori; Bando, Yoshio [International Center For Materials Nanoarchtectonics(MANA), National Institute for Materials Science (NIMS), 1-1 Namiki, Tsukuba, 305-0044 (Japan)

    2012-08-01

    We have studied the structural properties of the phase separation in Zn{sub 1-x}Cr{sub x}Te films grown by MBE with a relatively high Cr composition x{approx}0.2. In the combined analyses using TEM and EELS, it has been revealed that the Cr-aggregated regions are composed of precipitates of the hexagonal structure, which are formed in a particular crystallographic relation with the zinc-blende (ZB) structure of the matrix that the c-plane of the hexagonal structure nearly parallel to the (1 1 1) plane of the ZB structure. In the XRD measurements, the diffraction from the hexagonal precipitates has been detected in the {omega}-scan. From the measurements on the series of films grown at different temperatures, it has been suggested the hexagonal precipitates were formed in a larger quantity with the increase in growth temperature.

  12. Levitation Performance of Two Opposed Permanent Magnet Pole-Pair Separated Conical Bearingless Motors

    Science.gov (United States)

    Kascak, Peter; Jansen, Ralph; Dever, Timothy; Nagorny, Aleksandr; Loparo, Kenneth

    2013-01-01

    In standard motor applications, rotor suspension with traditional mechanical bearings represents the most economical solution. However, in certain high performance applications, rotor suspension without contacting bearings is either required or highly beneficial. Examples include applications requiring very high speed or extreme environment operation, or with limited access for maintenance. This paper expands upon a novel bearingless motor concept, in which two motors with opposing conical air-gaps are used to achieve full five-axis levitation and rotation of the rotor. Force in this motor is created by deliberately leaving the motor s pole-pairs unconnected, which allows the creation of different d-axis flux in each pole pair. This flux imbalance is used to create lateral force. This approach is different than previous bearingless motor designs, which require separate windings for levitation and rotation. This paper examines the predicted and achieved suspension performance of a fully levitated prototype bearingless system.

  13. The performance of an industrial wet high-intensity magnetic separator for the recovery of gold and uranium

    International Nuclear Information System (INIS)

    After bench-scale and pilot-plant tests in which it was shown that wet high-intensity magnetic separation (WHIMS) can achieve good recoveries of gold and uranium from Witwatersrand residues, a production-size machine was installed at a gold mine. The mechanical and metallurgical performance of this machine have been satisfactory, and the economics of the process are attractive. WHIMS can be combined with other unit operations like flotation for the optimization of overall gold and uranium recoveries. This concept is shown to be relevant, not only to operations for the retreatment of tailings, but to processes for the treatment of coarser material. In the latter, there is a saving in energy consumption compared with the energy required for the fine grinding of the total feed, and a material suitable for underground backfill can be produced. Improved, more cost-effective WHIMS machines currently under development are also described

  14. A Longitudinal Study of Abnormal Behaviour of Vertical Magnetic Field in Equatorial Stations Separated by 40

    Science.gov (United States)

    Thiagarajan, Arunachalam

    Variations of the geomagnetic componenets at three equatorial stations Ascension Island(7.95S,14.38W),Ad (9.03N,38.77E)and Trivandrum (8.48N,76.94E) are studied using hourly mean values of geo-magnetic componenents.It is shown that the Sq current system have shown a new type of Sq current distribution dierent from those associated with normal or counter electrojet(EEJ) events on 30 July 1995.This abnormal feature described seems to be a rare phenomenon. Both the horizontal and the vertical componenets of the geomagnetic eld at Addis ababa showed ab-normal maximum when compared with neighbouring days. The daily range of EEJ is found to exist in Indian longitudes did not show any correlation with this event.This additional current system could be due to excitation of certain tidal modes.

  15. Incorporation of magnetic resonance water-fat separation into MR-guided near-infrared spectroscopy in the breast

    Science.gov (United States)

    Carpenter, C. M.; Pogue, B. W.; Paulsen, K. D.

    2009-02-01

    Magnetic resonance (MR) guided diffuse optical spectroscopy (DOS) has shown promise in several case studies in aiding the characterization of breast lesions[1, 2]. It has been proposed that the increased quantification and resolution with a priori structural guidance yields higher diagnostic value in characterizing tumors. To date, these systems have merged MR anatomical recovery with optical contrast recovery. However, the MR has a wealth of spectral and functional data that may aid in further improving lesion characterization by appending both new and overlapping physiological information to optical methods. It has been well documented that spectral recovery of water and lipids is inaccurate with few wavelengths. Yet, recovery of these chromophores is important both because of the possible importance of these as indicators of breast cancer, adema, and inflammation. In addition, crosstalk between water and oxyhemoglobin may lead to erroneous tissue properties, which may affect lesion diagnosis. The use of multiple MR sequences with DOS enables the separation of water and lipids via MRI, and improves recovery of tissue oxygenation and hemoglobin content. However, in most cases, MRI is not a quantitative device; this paper investigates the best reconstruction methods to incorporate this data into the optical reconstruction for quantitatively accurate chromophore recovery in the presence of imperfect MR water/fat separation. Specifically, it investigates whether incorporating water/fat information directly or through a maximum likelihood algorithm yields the optimal solution both in terms of reduced crosstalk between oxyhemoglobin and water, and compares results to having no priori knowledge of water and fat.

  16. Separation of quadrupolar and magnetic contributions to spin-lattice relaxation in the case of a single isotope

    CERN Document Server

    Suter, A; Ross, J; Brinkmann, D

    1999-01-01

    We present a NMR pulse double-irradiation method which allows one to separate magnetic from quadrupolar contributions in the spin-lattice relaxation. The pulse sequence fully saturates one transition while another is observed. In the presence of a Delta m = 2 quadrupolar contribution, the intensity of the observed line is altered compared to a standard spin-echo experiment. We calculated analytically this intensity change for spins I=1, 3/2, 5/2, thus providing a quantitative analysis of the experimental results. Since the pulse sequence we used takes care of the absorbed radio-frequency power, no problems due to heating arise. The method is especially suited when only one NMR sensitive isotope is available. Different cross-checks were performed to prove the reliability of the obtained results. The applicability of this method is demonstrated by a study of the plane oxygen 17O (I = 5/2) in the high-temperature superconductor YBa_2Cu_4O_8: the 17O spin-lattice relaxation rate consists of magnetic as well as qu...

  17. Separation and characterization of alkyl phenol formaldehyde resins demulsifier by adsorption chromatography, gel permeation chromatography, infrared spectrometry and nuclear magnetic resonance spectroscopy

    International Nuclear Information System (INIS)

    This paper deals with the separation and characterization of alkyl phenol formaldehyde resins demulsifier by infrared spectrometry and nuclear magnetic resonance spectroscopy after separation of the different surfactants and low molecular additives by adsorption chromatography. Firstly, the types of surfactants are identified by methylene blue chloride-chloroform test method and the elemental analysis such as Ca, K, Mg, Na, P, S and N. Then, the different surfactants and low molecular components are separated by adsorption chromatography after parts of low molecular components are dried in an oven, and the molecular weight distribution is measured by gel permeation chromatography also. Finally, the separated surfactants are determined by Fourier transform infrared (FTIR) spectrometry and nuclear magnetic resonance (NMR) spectroscopy. The distortionless enhancement by polarization transfer (DEPT), H, C correlated spectroscopy (H, C-COSY), H, H correlated spectroscopy (H, H-COSY) and heteronuclear multiple-bond correlation (HMBC) spectroscopy are applied to determine the molecular structures

  18. Separation and characterization of alkyl phenol formaldehyde resins demulsifier by adsorption chromatography, gel permeation chromatography, infrared spectrometry and nuclear magnetic resonance spectroscopy

    Energy Technology Data Exchange (ETDEWEB)

    Li Jinxin [China University of Petroleum-Beijing, 18 Fuxue Road, Changping, Beijing 102249 (China)]. E-mail: lijinxin88@hotmail.com; Zhang Jinjun [China University of Petroleum-Beijing, 18 Fuxue Road, Changping, Beijing 102249 (China); Yang Haijun [Tsinghua University, Beijing 100084 (China); Ning Yongcheng [Tsinghua University, Beijing 100084 (China)

    2006-05-04

    This paper deals with the separation and characterization of alkyl phenol formaldehyde resins demulsifier by infrared spectrometry and nuclear magnetic resonance spectroscopy after separation of the different surfactants and low molecular additives by adsorption chromatography. Firstly, the types of surfactants are identified by methylene blue chloride-chloroform test method and the elemental analysis such as Ca, K, Mg, Na, P, S and N. Then, the different surfactants and low molecular components are separated by adsorption chromatography after parts of low molecular components are dried in an oven, and the molecular weight distribution is measured by gel permeation chromatography also. Finally, the separated surfactants are determined by Fourier transform infrared (FTIR) spectrometry and nuclear magnetic resonance (NMR) spectroscopy. The distortionless enhancement by polarization transfer (DEPT), H, C correlated spectroscopy (H, C-COSY), H, H correlated spectroscopy (H, H-COSY) and heteronuclear multiple-bond correlation (HMBC) spectroscopy are applied to determine the molecular structures.

  19. Wet high-intensity magnetic separation for the concentration of Witwatersrand gold-uranium ores and residues

    International Nuclear Information System (INIS)

    Wet high-intensity magnetic separation (WHIMS) for the concentration of gold and uranium was tested on many Witwatersrand cyanidation residues, and on some ores and flotation tailings. The results varied, but many indicated recoveries of over 60 per cent of the gold and uranium. The main source of loss is the inefficiency of WHIMS for material of smaller particle size than 20?m. The recoveries in the continuous tests were lower than those in the batch tests. The continuous tests indicated an operational difficulty that could be experienced in practice, namely the tendency for wood chips and ferromagnetic particles to block the matrix of the separator. It was decided that a solution to the problem lies in the modification of the separator to allow continuous removal of the matrix for cleaning. A system has been developed for this purpose and is being demonstrated on a pilot-plant scale. Promising results were obtained in tests on a process that combines a coarse grind, gravity concentration, and WHIMS. In the gravity-concentration step, considerable recoveries, generally over 50 per cent, of high-grade pyrite were obtained, together with high recoveries of gold and moderate, but possibly important, recoveries of uranium. A simple model describing the operation of the WHIMS machine in terms of the operating parameters is described. This should reduce the amount of empirical testwork required for the optimization of operating conditions and should provide a basis for scditions and should provide a basis for scale-up calculations. The economics of the WHIMS process is discussed

  20. Evidence for Two Separate but Interlaced Components of the Chromospheric Magnetic Field

    Science.gov (United States)

    Muglach, K.; Reardon, K. P.; Wang, Y.-M.; Warren, H. P.

    2012-01-01

    Chromospheric fibrils are generally thought to trace out horizontal magnetic fields that fan out from flux concentrations in the photosphere. A high-resolution (0.2") image taken in the core of the Ca IJ854.2 nm line shows the dark fibrils within an active region remnant as fine, loop-like features that are aligned parallel to each other and have lengths on the order of a supergranular diameter (approx.30 Mm). Comparison with a line-of-sight magnetogram confirms that the fibrils are centered above intranetwork areas, with one end rooted just inside the neighboring plage or strong unipolar network but the other endpoint less clearly defined. Focusing on a particular arcade-like structure lying entirely on one side of a filament channel (large-scale polarity inversion), we find that the total amount of positive-polarity flux underlying this "fibril arcade' is 50 times greater than the total amount of negative-polarity flux. Thus, if the fibrils represent closed loops, they must consist of very weak fields (in terms of flux density), which are interpenetrated by a more vertical field that contains most of the flux. This surprising result suggests that the fibrils in unipolar regions connect the network to the nearby intranetwork flux, while the bulk of the network flux is diverted upward into the corona and connects to remote regions of the opposite polarity. We conclude that the chromospheric field near the edge of the network has an interlaced structure resembling that in sunspot penumbrae, with the fibrils representing the low-lying horizontal flux that remains trapped within the highly nonpotential chromospheric layer.

  1. Evidence for Two Separate But Interlaced Components of the Chromospheric Magnetic Field

    Science.gov (United States)

    Muglach, Karin; Reardon, K.; Wang, Y.; Warren, H.

    2012-05-01

    Chromospheric fibrils are generally thought to trace out horizontal magnetic fields that fan out from flux concentrations in the photosphere. A high-resolution (0.2") image taken in the core of the Ca II 854.2 nm line shows the dark fibrils within an active region remnant as fine, looplike features that are aligned parallel to each other and have lengths on the order of a supergranular diameter ( 30 Mm). Comparison with a line-of-sight magnetogram confirms that the fibrils are centered above intranetwork areas, with one end rooted just inside the neighboring plage or strong unipolar network but the other endpoint less clearly defined. Focusing on a particular arcade-like structure lying entirely on one side of a filament channel (large-scale polarity inversion), we find that the total amount of positive-polarity flux underlying this ``fibril arcade'' is 50 times greater than the total amount of negative-polarity flux. Thus, if the fibrils represent closed loops, they must consist of very weak fields (in terms of flux density), which are interpenetrated by a more vertical field that contains most of the flux. This surprising result suggests that the fibrils in unipolar regions connect the network to the nearby intranetwork flux, while the bulk of the network flux is diverted upward into the corona and connects to remote regions of the opposite polarity. We conclude that the chromospheric field near the edge of the network has an interlaced structure resembling that in sunspot penumbrae, with the fibrils representing the low-lying horizontal flux that remains trapped within the highly nonpotential chromospheric layer.

  2. The effects of magnetic separation on cryopreserved bovine spermatozoa motility, viability and cryo-capacitation status.

    Science.gov (United States)

    Faezah, S S M; Zuraina, F M Y; Farah, J H F; Khairul, O; Hilwani, N I; Iswadi, M I; Fang, C N; Zawawi, I; Abas, O M; Fatimah, S I

    2014-08-01

    Cryopreservation is a technique used to preserve cells for long-time storage. It is widely used in agriculture to store male gametes in liquid nitrogen. The aim of this study was to determine the optimum thawing temperature and time for samples subjected to annexin V magnetic-activated cell sorting (AnMACS) as the sperm preparation technique. Pooled semen samples from three ejaculates were divided into two groups. The treatment group was subjected both to AnMACS and to being cryopreserved, whilst the control group was cryopreserved directly without MACS. Post-thaw analysis was carried out for samples thawed at either 20°C for 13 s, 37°C for 30 s, 40°C for 7 s, 60°C for 6 s or 80°C for 5 s. Sperm kinematics, viability and capacitation status were determined for samples subjected to all thawing temperatures described. Results showed that thawing at 37°C for 13 s for MACS-processed samples was a superior option compared with other thawing procedures; there was a significant difference in P < 0.05 values for curvilinear velocity (VCL ?m/s) and sperm straightness (STR %) when samples were thawed at 40°C for 7 s, with fewer capacitated spermatozoa (P < 0.05) when samples were thawed at 37°C for 30 s, 40°C for 7 s or 60°C for 6 s. Hence, we can speculate that the use of AnMACS as the sperm preparation technique can somehow enhance sperm cryosurvival rate after cryopreservation, however the fertilization potential of these cells has yet to be determined. PMID:23237064

  3. Magnetic source separation in the outer core. Introducing the SCOR-field

    International Nuclear Information System (INIS)

    Complete text of publication follows. We present evidence that the primary source of Earth's axial dipole (AD) is physically distinct from sources responsible for the rest of the geomagnetic field. Support for this claim comes from correlations between the structure of the historic non-axial dipole (NAD) field and transitional paleomagnetic behavior recorded in lavas during the early Brunhes Chron. 40Ar/39Ar age determinations of lavas from West Eifel, Germany, indicate the recording of five excursions spanning ?200 kyr, including the Big Lost Event (?580 ka). Transitional lavas from Tahiti also record the Big Lost as well as the Matuyama-Brunhes reversal. Virtual geomagnetic poles (VGPs) recorded at West Eifel are spread across Eurasia, while those recorded on Tahiti during the two events are associated with the same tightly clustered location west of Australia - the site of the most intense NAD flux feature since direct field measurements started some 400 years ago. The differing locations and amounts of spread of transitional VGPs match - at both sites - virtual poles determined for the historic NAD-field. We contend that (1) the field generated by deep convective columns near the tangent cylinder is the primary source for the AD; and (2) the field arising from flux concentrations held and controlled by lower mantle conditions is the primary source for the NAD. Since there most certainly is a small contribution to the AD term (g10) associarm (g10) associated with mantle-held sources, we define this field as the Shallow-Core-Generated (SCOR) field. Paleomagnetic data from Tahiti and Australia strongly suggest that the Australasian flux feature is long-lived, regionally dominating the field when the strength of the main AD had significantly weakened or vanished. We argue that recurrence of transitional VGPs observed over geologic time indicates that (1) the entire field does not reverse as a single unit, and (2) field sources exist in the core that are sufficiently separated to be in 'poor communication.' It follows that subsequent work on spherical harmonic-based field descriptions may now incorporate an understanding of a dichotomy of spatial-temporal dynamo processes.

  4. Cluster glass magnetism in the phase-separated Nd2/3Ca1/3MnO3 perovskite

    OpenAIRE

    Fertman, Elena; Dolya, Sergiy; Desnenko, Vladimir; Beznosov, Anatoly; Kajnakova, Marcela; Feher, Alexander

    2013-01-01

    A detailed study of the low-temperature magnetic state and the relaxation in the phase-separated colossal magnetoresistance Nd2/3Ca1/3MnO3 perovskite has been carried out. Clear experimental evidence of the cluster-glass magnetic behavior of this compound has been revealed. Well defined maxima in the in-phase linear ac susceptibility $\\chi ^{/}(T)$ were observed, indicative of the magnetic glass transition at $T_{g}$ = 60 K. Strongly divergent zero-field-cooled and field-coo...

  5. Silence of magnetic layers to magnetoresistive process and electronic separation at low temperatures in $(La,Sm)Mn_{2}Ge_{2}$

    CERN Document Server

    Sampathkumaran, E V; Paulose, P L; Majumdar, S N; Majumdar, Subham

    2000-01-01

    A closer look at the temperature (T) dependence of magnetoresistance (MR) oftwo polycrystalline magnetic compounds, LaMn$_2$Ge$_2$ and SmMn$_2$Ge$_2$,previously reported by us, is made. A common feature for both these compoundsis that the low temperature MR is positive (say, below, 30 K) in spite of thefact that both are ferromagnetic at such low temperatures; in addition, MR as afunction of magnetic field (H) does not track magnetization (M) in the sensethat M saturates at low fields, while MR varies linearly with H. Theseobservations suggest that the magnetic layers interestingly do not dominate lowtemperature magnetotransport process. Interestingly enough, as the T isincreased, say around 100 K, these magnetic layers dominate MR process asevidenced by the tracking of M and MR in SmMn$_2$Ge$_2$. These results temptsus to propose that there is an unusual "electronic separation" for MR processas the T is lowered in this class of compounds.

  6. Magnetic, durable, and superhydrophobic polyurethane@Fe3O4@SiO2@fluoropolymer sponges for selective oil absorption and oil/water separation.

    Science.gov (United States)

    Wu, Lei; Li, Lingxiao; Li, Bucheng; Zhang, Junping; Wang, Aiqin

    2015-03-01

    Magnetic, durable, and superhydrophobic polyurethane (PU) sponges were fabricated by chemical vapor deposition (CVD) of tetraethoxysilane (TEOS) to bind the Fe3O4 nanoparticles tightly on the sponge and then dip-coating in a fluoropolymer (FP) aqueous solution. The sponges were characterized using scanning electron microscopy and other analytical techniques. The effects of CVD time of TEOS and FP concentration on wettability, mechanical properties, oil absorbency, and oil/water selectivity of the sponges were also investigated. The sponges exhibit fast magnetic responsivity and excellent superhydrophobicity/superoleophilicity (CAwater = 157° and CAoil ? 0°). The sponges also show very high efficiency in oil/water separation and could, driven by a magnet, quickly absorb floating oils on the water surface and heavy oils under water. Moreover, the PU@Fe3O4@SiO2@FP sponges could be used as membranes for oil/water separation and for continuous separation of large amounts of oil pollutants from the water surface with the help of a pump. The in turn binding of Fe3O4 nanoparticles, SiO2, and FP can also improve mechanical properties of the PU sponge. The sponges maintain the superhydrophobicity even when they are stretched with 200% strain or compressed with 50% strain. The sponges also show excellent mechanical stability, oil stability, and reusability in terms of superhydrophobicity and oil absorbency. The magnetic, durable, and superhydrophobic PU sponges are very promising materials for practical oil absorption and oil/water separation. PMID:25671386

  7. Synthesis and characterization of magnetic hexacyanoferrate (II) polymeric nanocomposite for separation of cesium from radioactive waste solutions.

    Science.gov (United States)

    Sheha, Reda R

    2012-12-15

    Nanocrystalline potassium zinc hexacyanoferrate loaded on nanoscale magnetite substrate was successfully synthesized for significantly enhanced removal of cesium from low-level radioactive wastes. A description was given for preparation and properties of these precursors. The physicochemical properties of these nanocomposites were determined using different techniques including Fourier transform infrared spectroscopy (FTIR), X-ray diffraction (XRD), thermogravimetric analysis (TGA), scanning electron microscopy (SEM), and energy dispersive spectroscopy (EDS). Data clarified that supporting potassium zinc hexacyanoferrates on iron ferrite nanoparticles increased their thermal stability. Further, Fourier transform infrared spectra confirmed that the nanocomposites were well coordinated and incorporated in the polymer matrix. The average particle sizes, of these nanoparticles, determined by SEM had a good agreement with XRD results. Based on characterization data, the prepared zinc hexacyanoferrates were proposed to have a zeolitic rhombohedral structure with cavities can host alkali metal ions and water molecules. The magnetic analysis showed a super-paramagnetic behavior. Batch technique was applied to evaluate the influences of initial pH value, contact time, and competing cations on the efficiency of cesium removal. The sorption process was fast initially, and maximum separation was attained within 2h of contact. Cesium exchange was independent from pH value and deviate from ideal exchange phenomena. In neutral solutions, Cs(+) was retained through exchange with K(+); however, in acidic solution, phase transformation was proposed. Sorption capacity of these materials attained values amounted 1965 mg g(-1). The synthesized nanocomposites exhibited different affinities toward Cs(I), Co(II), and Eu(III) elements and showed a good ability to separate them from each other. PMID:23000210

  8. ZnO nanostructured film deposition using the separated pulsed laser deposition (SPLD) assisted by electric and magnetic drift motion

    International Nuclear Information System (INIS)

    We have developed the separated pulsed laser deposition (SPLD) technique to prepare high quality ZnO based films exhibiting uniform and droplet-free properties. This SPLD consists of an ablation chamber and a deposition chamber which can be independently evacuated under different ambient gases. The gas species and the pressures in both chambers can be arbitrarily chosen for the specific deposition such as nanostructured films and nanoparticles. The ablation chamber is a stainless steel globe and the deposition chamber is a quartz tube connected to a metallic conic wall with an orifice. We used a KrF excimer laser with ? = 248 nm and 25 ns pulse duration. The different gas conditions in two chambers allow us to realize optimal control of the plasma plume, the gas phase reaction and the film growth by applying the bias voltage between the conic wall and the substrate under the magnetic field. We can expect that at appropriate pressures the electric and magnetic field motion (E x B azimuthal drift velocity) gives significant influences on film growth. We have deposited ZnO thin films at various pressures of ablation chamber (Pab) and deposition chamber (Pd). The deposition conditions used here were laser fluence of 3 J/cm2, laser shot number of 30,000, Pab of 0.67-2.67 Pa (O2 or Ar), Pd of 0.399-2.67 Pa (O2), and substrate temperature of 400 deg. C. Particle-free and uniform ZnO films were obtained at Pab of 0.67 Pa (Ar) and Pd of 1.33 Pd at Pab of 0.67 Pa (Ar) and Pd of 1.33 Pa (O2). The ZnO film showed high preferential orientation of (002) plane, optical band gap of 2.7 eV, grain size of 42 nm and surface roughness of 1.2 nm

  9. Synthesis of magnetic molecularly imprinted polymers for the selective separation and determination of metronidazole in cosmetic samples.

    Science.gov (United States)

    Liu, Min; Li, Xiao-Yan; Li, Jun-Jie; Su, Xiao-Meng; Wu, Zong-Yuan; Li, Peng-Fei; Lei, Fu-Hou; Tan, Xue-Cai; Shi, Zhan-Wang

    2015-05-01

    In this study, novel magnetic molecularly imprinted polymers (MMIPs) were developed as a sorbent for solid-phase extraction (SPE) and used for the selective separation of metronidazole (MNZ) in cosmetics; MNZ was detected by high-performance liquid chromatography (HPLC). First, magnetic Fe3O4 nanoparticles (NPs) were prepared by the co-precipitation of Fe(2+)and Fe(3+) ions in an ammonia solution; then oleic acid (OA) was modified onto the surface of Fe3O4NPs. Finally, the MMIP was prepared by aqueous suspension polymerization, involving the copolymerization of Fe3O4NPs@OA with MNZ as the template molecule, methacrylic acid (MAA) as the functional monomer, ethylene glycol maleic rosinate acrylate (EGMRA) as the cross-linking agent, and 2,2-azobisisobutyronitrile (AIBN) as the initiator. The MMIP materials showed high selective adsorption capacity and fast binding kinetics for MNZ; the maximum adsorption amount of the MMIP to MNZ was 46.7 mg/g. The assay showed a linear range from 0.1 to 20.0 ?g/mL for MNZ with the correlation coefficient 0.999. The relative standard deviations (RSD) of intra- and inter-day ranging from 0.71 to 2.45 % and from 1.06 to 5.20 % were obtained. The MMIP can be applied to the enrichment and determination of MNZ in cosmetic products with the recoveries of spiked toner, powder, and cream cosmetic samples ranging from 90.6 to 104.2, 84.1 to 91.4, and 90.3 to 100.4 %, respectively, and the RSD was <3.54 %. PMID:25749799

  10. Design of a core-shell type immuno-magnetic separation system and multiplex PCR for rapid detection of pathogens from food samples.

    Science.gov (United States)

    Ozalp, V Cengiz; Bayramoglu, Gulay; Arica, M Yakup; Oktem, H Avni

    2013-11-01

    We report an immuno-magnetic separation system developed by the immobilization of pathogen-specific antibodies on the core-shell magnetic beads. The magnetic beads were grafted with glycidylmethacrylate (GMA) using surface-initiated atom transfer radical polymerization (SI-ATRP). For immuno-magnetic separation (IMS) of target bacterial cells from others, antibodies for Escherichia coli and Salmonella enterica serovar Typhimurium cells were immobilized on the magnetic beads via glutaraldehyde coupling reaction. Our IMS system successfully separated Salmonella cells when the concentrations of target (i.e., Salmonella) and interfering (i.e., E. coli) cells were at the same level. Polymerase chain reaction (PCR) assays amplifying the rfb/rfbE region of the E. coli genome and a 647-bp fragment of the invA region of Salmonella were performed as the specific selection to accurately confirm the presence of E. coli and Salmonella, respectively. IMS and multiplex PCR methods can be used for specific and quantitative detection of pathogens from food samples. Thus, this study developed a reliable and direct system for rapid detection of Salmonella and E. coli in food samples. In addition, IMS method could be easily adapted to detect other pathogens by selecting the pertinent antibody. PMID:24048640

  11. Preparation of anionic polyelectrolyte modified magnetic nanoparticles for rapid and efficient separation of lysozyme from egg white.

    Science.gov (United States)

    Chen, Jia; Lin, Yuexin; Jia, Li

    2015-04-01

    Poly(sodium 4-styrenesulfonate) modified magnetic nanoparticles (PSS-MNPs) were successfully synthesized and characterized by transmission electron microscopy, scanning electron microscopy, zeta potential, vibrating sample magnetometry, and Fourier-transform infrared spectrometry. The PSS-MNPs were found to enable effective separation of lysozyme from egg white. The impacts of solution pH, ionic strength, and contact time on the adsorption process were investigated. The adsorption kinetic data were well fitted using a pseudo-second-order kinetic model and the adsorption equilibrium can be reached in 3 min. The adsorption isotherm data could be well described by the Langmuir equation. The maximum adsorption capacity of PSS-MNPs for lysozyme was calculated to be 476.2 mg g(-1) according to the Langmuir adsorption isotherm. The fast and efficient adsorption of lysozyme by PSS-MNPs was mainly based on electrostatic interactions between them. The adsorbed lysozyme can be eluted using 20mM phosphate buffer (pH 7.0) containing 1.0M NaCl with a recovery of 96%. The extracted lysozyme from egg white demonstrated high purity, retaining about 90.7% of total lysozyme activity. PMID:25728660

  12. Usefulness of two-point Dixon fat-water separation technique in gadoxetic acid-enhanced liver magnetic resonance imaging

    Science.gov (United States)

    Ding, Ying; Rao, Sheng-Xiang; Chen, Cai-Zhong; Li, Ren-Chen; Zeng, Meng-Su

    2015-01-01

    AIM: To compare differences between volumetric interpolated breath-hold examination (VIBE) using two-point Dixon fat-water separation (Dixon-VIBE) and chemically selective fat saturation (FS-VIBE) with magnetic resonance imaging examination. METHODS: Forty-nine patients were included, who were scanned with two VIBE sequences (Dixon-VIBE and FS-VIBE) in hepatobiliary phase after gadoxetic acid administration. Subjective evaluations including sharpness of tumor, sharpness of vessels, strength and homogeneity of fat suppression, and artifacts that were scored using a 4-point scale. The liver-to-lesion contrast was also calculated and compared. RESULTS: Dixon-VIBE with water reconstruction had significantly higher subjective scores than FS-VIBE in strength and homogeneity of fat suppression (< 0.0001) but lower scores in sharpness of tumor (P < 0.0001), sharpness of vessels (P = 0.0001), and artifacts (P = 0.034). The liver-to-lesion contrast on Dixon-VIBE images was significantly lower than that on FS-VIBE (16.6% ± 9.4% vs 23.9% ± 12.1%, P = 0.0001). CONCLUSION: Dixon-VIBE provides stronger and more homogenous fat suppression than FS-VIBE, while has lower clarity of focal liver lesions in hepatobiliary phase after gadoxetic acid administration. PMID:25945017

  13. Material processing in high static magnetic field. A review of an experimental study on levitation, phase separation, convection and texturation

    OpenAIRE

    Beaugnon, E.; Bourgault, D.; Braithwaite, D.; Rango, P.; Perrier La Bathie, R.; Sulpice, Andre?; Tournier, R.

    1993-01-01

    An inhomogeneous magnetic field exerts a force on magnetic materials and can be used either to compensate gravity, control convection in a magnetic liquid or modify the microstructure of a solidified multiphased system where the phases exhibit dilferent magnetic susceptibilities. A homogeneous field may produce a preferred crystallographic alignment in systems which exhibit an anisotropy of their magnetic susceptibility near their melting point. We present an experimental study of those ef[ e...

  14. Magnetically separable hybrid CdS-TiO2-Fe3O4 nanomaterial: Enhanced photocatalystic activity under UV and visible irradiation

    International Nuclear Information System (INIS)

    Magnetically separable photocatalyst of TiO2-CdS-Fe3O4@SiO2 nanocomposite was successfully prepared through a microwave heating method. The products exhibit enhanced photocatalystic activity which is more efficient than that of pure CdS and Degussa P25 TiO2 toward the degradation of RhB under both UV and visible irradiation. This is attributed to the charge separation and transformation from CdS to TiO2. The hysteresis loop of TiO2-CdS-Fe3O4@SiO2 nanocomposite indicates an excellent magnetic property with the saturated magnetization of 9 emu/g. We also show the fast magnetic separation behaviour of the TiO2-CdS-Fe3O4@SiO2 nanocomposite to remove and recycle the photocatalyst from the solution. These indicate TiO2-CdS-Fe3O4@SiO2 nanocomposite is an effective and convenient recyclable photocatalyst.

  15. Magnetically separable hybrid CdS-TiO{sub 2}-Fe{sub 3}O{sub 4} nanomaterial: Enhanced photocatalystic activity under UV and visible irradiation

    Energy Technology Data Exchange (ETDEWEB)

    Bian, Xiaofang; Hong, Kunquan, E-mail: hongkq@gmail.com; Liu, Liqing; Xu, Mingxiang, E-mail: mxxu@seu.edu.cn

    2013-09-01

    Magnetically separable photocatalyst of TiO{sub 2}-CdS-Fe{sub 3}O{sub 4}@SiO{sub 2} nanocomposite was successfully prepared through a microwave heating method. The products exhibit enhanced photocatalystic activity which is more efficient than that of pure CdS and Degussa P25 TiO{sub 2} toward the degradation of RhB under both UV and visible irradiation. This is attributed to the charge separation and transformation from CdS to TiO{sub 2}. The hysteresis loop of TiO{sub 2}-CdS-Fe{sub 3}O{sub 4}@SiO{sub 2} nanocomposite indicates an excellent magnetic property with the saturated magnetization of 9 emu/g. We also show the fast magnetic separation behaviour of the TiO{sub 2}-CdS-Fe{sub 3}O{sub 4}@SiO{sub 2} nanocomposite to remove and recycle the photocatalyst from the solution. These indicate TiO{sub 2}-CdS-Fe{sub 3}O{sub 4}@SiO{sub 2} nanocomposite is an effective and convenient recyclable photocatalyst.

  16. Magnetically separable hybrid CdS-TiO2-Fe3O4 nanomaterial: Enhanced photocatalystic activity under UV and visible irradiation

    Science.gov (United States)

    Bian, Xiaofang; Hong, Kunquan; Liu, Liqing; Xu, Mingxiang

    2013-09-01

    Magnetically separable photocatalyst of TiO2-CdS-Fe3O4@SiO2 nanocomposite was successfully prepared through a microwave heating method. The products exhibit enhanced photocatalystic activity which is more efficient than that of pure CdS and Degussa P25 TiO2 toward the degradation of RhB under both UV and visible irradiation. This is attributed to the charge separation and transformation from CdS to TiO2. The hysteresis loop of TiO2-CdS-Fe3O4@SiO2 nanocomposite indicates an excellent magnetic property with the saturated magnetization of 9 emu/g. We also show the fast magnetic separation behaviour of the TiO2-CdS-Fe3O4@SiO2 nanocomposite to remove and recycle the photocatalyst from the solution. These indicate TiO2-CdS-Fe3O4@SiO2 nanocomposite is an effective and convenient recyclable photocatalyst.

  17. Preparations and photocatalytic degradation of methyl orange in water on magnetically separable Bi12TiO20 supported on nickel ferrite

    OpenAIRE

    Shihong Xu, Wenfeng Shangguan

    2007-01-01

    A magnetically separable photocatalyst Bi12TiO20/SiO2/NiFe2O4 (BSN) with a typical ferromagnetic hysteresis was prepared by a simple process: the magnetic 200 wt% SiO2/NiFe2O4 (SN) dispersion prepared by a liquid catalytic phase transformation method and the visible-light-active photocatalyst Bi12TiO20 prepared by a simple coprecipitation processing were mixed, sonificated, dried, and calcined at 550 °C. The prepared photocatalyst showed high photocatalytic activity for the degradation of me...

  18. Recovery of very fine and ultra fine uraninite particles using superconducting high gradient magnetic separator: a case study with copper plant tailings

    International Nuclear Information System (INIS)

    Experimental studies were carried out on superconducting high gradient magnetic separator (SC-HGMS), designed and developed in BARC, on a low grade (assaying 3O8) uranium ore feed prepared from Rakha copper plant tailings in which uranium occurs as uraninite. The earlier studies carried out on wet high intensity magnetic separator (WHIMS) showed that the uraninite recovery reduces when the particle size decreases below 20?m and it does not exceed 20% for particles below 5 ?m. The present studies show that the SC-HGMS is able to recover efficiently very fine and ultrafine uraninite particles and, the recovery is more than 60% particles even below 5 ?m. It is thus possible to achieve significant improvement in the overall uraninite recovery by use of WHIMS in tandem with SC-HGMS. (author). 5 refs., 1 fig., 1 tab

  19. Isolation of prostate cancer cell subpopulations of functional interest by use of an on-chip magnetic bead-based cell separator

    International Nuclear Information System (INIS)

    This work presents the design, fabrication and characterization of a modular magnetic bead-based cell separation device developed for the sequential sorting of a heterogeneous prostate cancer (CaP) cell population. The chief aim is cell sorting carried out on the basis of surface marker expression, serially selecting cellular subpopulations for capture by the use of antibody-coated magnetic beads. The markers of interest, prostate specific membrane antigen (PSMA) and CD10 were selected for their relevance to ongoing CaP development research. The separation device was fabricated out of plastic, by the use of cyclic olefin copolymer (COC) injection molding, nickel–iron electroplating and thermoplastic fusion bonding. Effective depletion and enrichment of cell subsets based on multiple surface markers was achieved. Various flow rates and incubation times were tested for optimizing the sorting procedure

  20. On the possibilities of radioactive beam production in application of a cyclotron and a magnetic separator for investigations of resonance processes of elastic scattering in inverse geometry

    International Nuclear Information System (INIS)

    A possibility of using a cyclotron and a magnetic separator system to get light nucleus radioactive beams for an investigation of the resonance elastic scattering is discussed. Mainly (p, n) reactions in reversed kinematics are used as a source of the radioactive nuclei. An analysis of (p, n) reaction yields is done and the main features of cross section behavior of the reactions are analyzed. 20 refs., 8 figs., 2 tabs

  1. Magnetic properties of phase separated Fe3O4-TiO2-SiO2 glasses prepared from a two-liquids immiscible melt

    International Nuclear Information System (INIS)

    The glassy composite materials were prepared by quenching the phase separated melts in two-liquids immiscibility region of Fe3O4-TiO2-SiO2 ternary system. The fine phase-separation textures which consisted of Fe-Ti rich phase and Si rich one were formed in the samples, and the precipitation of Fe3O4-TiO2 solid solution was observed in the samples of the specific compositions. The samples containing Fe3O4-TiO2 solid solution showed ferrimagnetic properties on their magnetization curves. In low Fe3O4-TiO2 content, coercivity increased with increase of Fe3O4-TiO2 content since the precipitated particles in the samples grew and had single magnetic domain. In high Fe3O4-TiO2 content, the coercivity decreased with increase of Fe3O4-TiO2 content because the magnetostatical interparticle interaction among the precipitated particles appeared. These results indicate that the magnetic properties of the composite materials owing to the crystalline phase and its size can be controlled by utilizing the phase separation in this system

  2. Improved accuracy of U-Pb zircon dating by selection of more concordant fractions using a high gradient magnetic separation technique

    International Nuclear Information System (INIS)

    A loop of soft iron wire or a paper clip or a ferromagnetic grid mounted between the poles of an electromagnet picks up and allows further magnetic separation of zircons previously found to be non-magnetic on a Frantz Isodynamic Separator. Tests on previously analysed samples indicate that most such zircons that are fairly discordant (say approximately 10%) can be picked up and isolated from associated grains that are more concordant. Tests on new samples indicate that even when most grains can be picked up the last few percent of the sample contain less uranium, and are more concordant than the bulk sample. The degree of discordance is the dominant factor affecting the uncertainty of U-Pb zircon ages both because of the error amplification in projections, and because the assumption of a simple two-stage system may not be valid. Only by eliminating or reducing discordance can errors approaching the uncertainty in a single analysis, say +- 2 m.y. for 2700 m.y. rocks, be achieved. Rutile normally concentrated with zircon as non-magnetic has been successfully removed from a small amount of low uranium zircon, using the high intensity separation technique. (author)

  3. Improved accuracy of U-Pb zircon dating by selection of more concordant fractions using a high gradient magnetic separation technique

    International Nuclear Information System (INIS)

    A loop of soft iron wire or a paper clip or a ferromagnetic grid mounted between the poles of an electromagnet picks up and allows further magnetic separation of zircons previously found to be non-magnetic on a Frantz Isodynamic Separator. Tests on previously analysed samples indicate that most such zircons that are fairly discordant (say approximately 10%) can be picked up and isolated from associated grains that are more concordant. Tests on new samples indicate that even when most grains can be picked up the last few percent of the sample contain less uranium, and are more concordant than the bulk sample. The degree of discordance is the dominant factor affecting the uncertainty of U-Pb zircon ages both because of the error amplification in projections, and because the assumption of a simple two-stage system may not be valid. Only by eliminating or reducing discordance can errors approaching the uncertainty in a single analysis, say +-2m.y. for 2700m.y. rocks, be achieved. Rutile normally concentrated with zircon as non-magnetic has been successfully removed from a small amount of low uranium zircon, using the high intensity separation technique. (author)

  4. Observation of dynamical spin-dependent electron interactions and screening in magnetic transitions via core-level multiplet-energy separations

    Energy Technology Data Exchange (ETDEWEB)

    Tober, Eric D.; Palomares, F. Javier; Ynzunza, Ramon X.; Denecke, Reinhard [Department of Physics, University of California Davis, Davis, CA 95616 (United States); Materials Sciences Division, Lawrence Berkeley National Laboratory, Berkeley, CA 94720 (United States); Morais, Jonder [Materials Sciences Division, Lawrence Berkeley National Laboratory, Berkeley, CA 94720 (United States); Liesegang, John [Materials Sciences Division, Lawrence Berkeley National Laboratory, Berkeley, CA 94720 (United States); Department of Physics, La Trobe University, Melbourne, VIC 3086 (Australia); Hussain, Zahid [Advanced Light Source, Lawrence Berkeley National Laboratory, Berkeley, CA 94720 (United States); Shick, Alexander B.; Pickett, Warren E. [Department of Physics, University of California Davis, Davis, CA 95616 (United States); Fadley, Charles S., E-mail: fadley@lbl.gov [Department of Physics, University of California Davis, Davis, CA 95616 (United States); Materials Sciences Division, Lawrence Berkeley National Laboratory, Berkeley, CA 94720 (United States)

    2013-08-15

    Highlights: ? Gd 5s and 4s multiplet splittings of Gd(0001) change during magnetic transitions. ?·Atomic multiplet theory and LDA+U calculations partially explain these results. ?·Provide a novel probe of dynamical spin-dependent screening/magnetic fluctuations. ? Suggest future experiments in a time-resolved mode, e.g. using free electron lasers. -- Abstract: The magnetic phase transitions for Gd(0 0 0 1) grown on W(1 1 0) – a bulk transition at 293 K and a surface transition about 85 K above this – are found to influence the energy separation of the Gd 5s and 4s core-photoelectron doublets. The 5s doublet separation ?E{sub 5s} changes over a range of temperatures spanning these transitions, and decreases by a maximum of 60 meV in this region, but then recovers its original value; the 4s doublet shows a smaller change in the reverse direction, which does not recover at high temperature. Some of these effects are semi-quantitatively understood from free-atom multiplet theory and from theoretical calculations based on all-electron LDA+U calculations including 4f electron correlation effects. However, the high-temperature behavior of the data also suggest a dynamical nature to these effects via spin-dependent electron screening that is influenced by magnetic fluctuations. Several avenues for studying such effects in a time-resolved manner in future experiments are discussed.

  5. Preparations and photocatalytic degradation of methyl orange in water on magnetically separable Bi12TiO20 supported on nickel ferrite

    Directory of Open Access Journals (Sweden)

    Shihong Xu, Wenfeng Shangguan, Jian Yuan, Jianwei Shi and Mingxia Chen

    2007-01-01

    Full Text Available A magnetically separable photocatalyst Bi12TiO20/SiO2/NiFe2O4 (BSN with a typical ferromagnetic hysteresis was prepared by a simple process: the magnetic 200 wt% SiO2/NiFe2O4 (SN dispersion prepared by a liquid catalytic phase transformation method and the visible-light-active photocatalyst Bi12TiO20 prepared by a simple coprecipitation processing were mixed, sonificated, dried, and calcined at 550 °C. The prepared photocatalyst showed high photocatalytic activity for the degradation of methyl orange in water under UV irradiation and visible-light irradiation (?>400 nm, and it was easy to be separated from a slurry-type photoreactor under the application of an external magnetic field, being one of promising photocatalysts for wastewater treatment. Transmission electron microscope (TEM and X-ray diffractometer (XRD were used to characterize the structure of the photocatalyst, indicating that the magnetic SN particles adhered to the surface of the Bi12TiO20 congeries. SiO2 layer round the surface of NiFe2O4 nanoparticles prevented effectively the injection of charges from TiO2 particles to NiFe2O4, which gave rise to the increase in photocatalytic activity.

  6. Observation of dynamical spin-dependent electron interactions and screening in magnetic transitions via core-level multiplet-energy separations

    International Nuclear Information System (INIS)

    Highlights: ? Gd 5s and 4s multiplet splittings of Gd(0001) change during magnetic transitions. ?·Atomic multiplet theory and LDA+U calculations partially explain these results. ?·Provide a novel probe of dynamical spin-dependent screening/magnetic fluctuations. ? Suggest future experiments in a time-resolved mode, e.g. using free electron lasers. -- Abstract: The magnetic phase transitions for Gd(0 0 0 1) grown on W(1 1 0) – a bulk transition at 293 K and a surface transition about 85 K above this – are found to influence the energy separation of the Gd 5s and 4s core-photoelectron doublets. The 5s doublet separation ?E5s changes over a range of temperatures spanning these transitions, and decreases by a maximum of 60 meV in this region, but then recovers its original value; the 4s doublet shows a smaller change in the reverse direction, which does not recover at high temperature. Some of these effects are semi-quantitatively understood from free-atom multiplet theory and from theoretical calculations based on all-electron LDA+U calculations including 4f electron correlation effects. However, the high-temperature behavior of the data also suggest a dynamical nature to these effects via spin-dependent electron screening that is influenced by magnetic fluctuations. Several avenues for studying such effects in a time-resolved manner in future experiments are discussed

  7. Magnetic phase separation in La0.67Ca0.37Mn0.9Fe0.1O3: a Moessbauer study

    International Nuclear Information System (INIS)

    Moessbauer measurement of La0.67Ca0.33Mn0.9Fe0.1O3 have been carried out from room temperature to 4.2 K with an applied magnetic fields. Moessbauer paramagnetic spectra of La0.67Ca0.33Mn0.9Fe0.1O3 were split into two doublets, even though Fe occurs at equivalent sites. Moessbauer spectra reveal that Fe substitutes for Mn as Fe3+. Moessbauer spectroscopy shows phase separation, both above and below the magnetic transition temperature (Tc). Below Tc, the spin orderings in the two phases are ferromagnetic (FM) and spin glass (SG) orderings, respectively. At low temperatures, SG phase converts into FM phase when the applied magnetic field increases. but only partially. (author)

  8. Magnetic field dependence of the magnetic phase separation in Pr1-xCaxMnO3 manganites studied by small-angle neutron scattering

    OpenAIRE

    Saurel, Damien; Brulet, Annie; Heinemann, Andre; Martin, Christine; Mercone, Silvana; Simon, Charles

    2006-01-01

    Transport properties of manganese oxides suggest that their colossal magnetoresistance (CMR) is due to percolation between ferromagnetic metallic (FM) clusters in an antiferromagnetic insulating (AFI) matrix. We have studied small-angle neutron scattering under applied magnetic field in CMR Pr1-xCaxMnO3 crystals for x around 0.33. Quantitative analysis of the small-angle magnetic neutron scattering shows that the magnetic heterogeneities take place at different scales. At th...

  9. The evaluation of the influence of drying the ore before the dry high - intensity magnetic separation on the efficiency production process of blastfurnace pellets in the Siderit Ni?ná Slaná plant

    OpenAIRE

    Kuffnerová Andrea; Spi?ák Ján

    2001-01-01

    In the contribution is described the evaluation of the influence of the parameters on the input to the dry high - intensity magnetic separation (SVIMS), on the technological production process of the blastfurnace pellets in the condition of the company ?elba, a.s., o.z. Siderit Ni?ná Slaná.By the dry high - intensity magnetic separation (SVIMS) separates siderite from inherent rock by the activity effect of the strong magnetic field of the electromagnets. The realisation of the dry high - int...

  10. Studies of sheath characteristics in a double plasma device with a negatively biased separating grid and a magnetic filter field

    International Nuclear Information System (INIS)

    A double plasma device has two regions: Source region and target region. These two regions are divided by a magnetic filter field. A grid is placed coplanar to the magnetic filter. To study the sheath structure in the target region, a metallic plate is placed at the center, which can be biased with respect to the chamber (ground) potential. Plasma is created in the source region by filament discharge technique. Plasma diffusing from the source region to the target region is subjected to the magnetic filter field and also an electric field applied on the grid. Plasma thus obtained in the target region forms a sheath on the biased plate. The influence of both the magnetic filter field and the electric field, applied between the grid and the chamber wall, on the sheath structure formed on the biased plate is studied. It is found that the magnetic filter field and the electric field change the sheath structure in different ways.

  11. Magnetically separable Fe3O4@SiO2@TiO2-Ag microspheres with well-designed nanostructure and enhanced photocatalytic activity

    International Nuclear Information System (INIS)

    Graphical abstract: An effective route has been developed to synthesize magnetic Fe3O4@SiO2@TiO2-Ag microspheres with well-defined core–shell nanostructure and enhanced photocatalytic activity. -- Highlights: • Controllable synthesis of core–shell structured Fe3O4@SiO2@TiO2-Ag magnetic nanocomposite. • The unique nanostructure of Fe3O4@SiO2@TiO2-Ag can improve the total photocatalytic performance. • An easy magnetically separable and recoverable process. -- Abstract: Major efforts in modern material chemistry are devoted to the design and fabrication of nanostructured systems with tunable physical–chemical properties for advanced catalytic applications. Here, a novel Fe3O4@SiO2@TiO2-Ag nanocomposite has been synthesized and characterized by a series of techniques including SEM, TEM, XRD, XPS as well as magnetization measurement and subsequently tested for the photocatalytic activities. The well-designed nanocomposite exhibits significantly superior activity to that of the commercial Degussa P25 thanks to the suppression of electron–hole pairs from recombination by Ag nanoparticles, and can be easily recycled by applying an external magnetic field while maintaining the catalytic activity without significant decrease even after running 10 times. The unique nanostructure makes Fe3O4@SiO2@TiO2-Ag a highly efficient, recoverable, stable, and cost-effective photocatalytic system offering broad opportunities in the field of catalyst synthesis and application

  12. Effect of an external magnetic field on a critical point for phase separation in a dusty plasma

    International Nuclear Information System (INIS)

    The effect of an external magnetic field on a critical point for phase transitions in a dusty plasma is investigated. It is shown that the ambient magnetic field increases the effective hard core radius of dust particles, which, in turn, would affect a critical point in terms of the Coulomb coupling parameter and the ratio between the inter-dust grain spacing and the dusty plasma Debye radius. The present result may be useful in understanding the phenomenon of liquid-vapor phase transitions in laboratory dusty plasmas that are held in an external magnetic field.

  13. Bifunctional magnetic nanobeads for sensitive detection of avian influenza A (H7N9) virus based on immunomagnetic separation and enzyme-induced metallization.

    Science.gov (United States)

    Wu, Zhen; Zhou, Chuan-Hua; Chen, Jian-Jun; Xiong, Chaochao; Chen, Ze; Pang, Dai-Wen; Zhang, Zhi-Ling

    2015-06-15

    Bifunctional magnetic nanobeads (bi-MBs) were fabricated by co-immobilizing target recognition molecules and signal molecules on a magnetic nanobead surface, which were used as both separation and enrichment carriers and signal carriers. The bi-MBs could capture and separate avian influenza A (H7N9) virus (H7N9 AIV) from complex samples efficiently based on the specific reaction between antigen-antibody and their good magnetic response, which simplified sample pretreatment and saved the detection time. Taking advantages of their high surface to volume ratio and rich surface functional groups, multiple alkaline phosphatase (ALP) signal molecules were tethered on the surface of bi-MBs which greatly amplified the detection signal. As an efficient signal amplification strategy, enzyme-induced metallization had been integrated with bi-MBs and anodic stripping voltammetry to construct an ultrasensitive electrochemical immunosensor for H7N9 AIV detection. Under the optimal conditions, the introduction of bi-MBs could amplify the detection signal in about four times compared with the same immunoassay without MBs, and the method showed a wide linear range of 0.01-20 ng/mL with a detection limit of 6.8 pg/mL. The electrochemical immunosensor provides a simple and reliable platform with high sensitivity and selectivity which shows great potential in early diagnosis of diseases. PMID:25643598

  14. Popcorn-shaped magnetic core-plasmonic shell multifunctional nanoparticles for the targeted magnetic separation and enrichment, label-free SERS imaging, and photothermal destruction of multidrug-resistant bacteria.

    Science.gov (United States)

    Fan, Zhen; Senapati, Dulal; Khan, Sadia Afrin; Singh, Anant Kumar; Hamme, Ashton; Yust, Brian; Sardar, Dhiraj; Ray, Paresh Chandra

    2013-02-18

    Over the last few years, one of the most important and complex problems facing our society is treating infectious diseases caused by multidrug-resistant bacteria (MDRB), by using current market-existing antibiotics. Driven by this need, we report for the first time the development of the multifunctional popcorn-shaped iron magnetic core-gold plasmonic shell nanotechnology-driven approach for targeted magnetic separation and enrichment, label-free surface-enhanced Raman spectroscopy (SERS) detection, and the selective photothermal destruction of MDR Salmonella DT104. Due to the presence of the "lightning-rod effect", the core-shell popcorn-shaped gold-nanoparticle tips provided a huge field of SERS enhancement. The experimental data show that the M3038 antibody-conjugated nanoparticles can be used for targeted separation and SERS imaging of MDR Salmonella DT104. A targeted photothermal-lysis experiment, by using 670 nm light at 1.5 W cm(-2) for 10 min, results in selective and irreparable cellular-damage to MDR Salmonella. We discuss the possible mechanism and operating principle for the targeted separation, label-free SERS imaging, and photothermal destruction of MDRB by using the popcorn-shaped magnetic/plasmonic nanotechnology. PMID:23296491

  15. A novel magnetically separable TiO2/CoFe2O4 nanofiber with high photocatalytic activity under UV–vis light

    International Nuclear Information System (INIS)

    Graphical abstract: A novel magnetically separable composite photocatalyst TiO2/CoFe2O4 nanofiber was prepared by sol–gel method and electrospinning technique, which can be reclaimed with a magnet, and the decolorizing efficiency of MB solution reached 95.87%. Highlights: ? The composite TiO2/CoFe2O4 nanofibers with diameter of 110 ± 28 nm have been successfully synthesized by the combination of sol–gel method and electrospinning technique. ? The presence of Co2+ or/and Fe3+ ions may occupy some of the lattice sites of TiO2 to form an iron–titanium solid solution and narrow the band gap, which broadens the response region of visible light. ? The resultant nanofibers not only have high decomposition efficiency with methylene blue (MB) under the UV irradiation, which is close to that of Degussa P25, but also can be separated with a magnet and avoid the secondary pollution of the treated water. -- Abstract: A novel magnetically separable heterogeneous photocatalyst TiO2/CoFe2O4 nanofiber was prepared by sol–gel method and electrospinning technology, followed by heat treatment at 550 °C for 2 h. The phase structure, morphology and magnetic property of the composite nanofibers were characterized by X-ray diffraction, scanning electron microscopy, transmission electron microscope and vibrating sample magnetometer analysis. The photocatalytic studies of TiO2/CoFe2O4 fibers suggested that the presence of CoFe2O4 not only enhanced the absorbance of UV light, but also broadened the response region to visible light. The decolorizing efficiency of methylene blue (MB) solution reaches 95.87% over TiO2/CoFe2O4 nanofibers under 300 W Hg lamp after 5 h, which is close to that of Degussa P25. Furthermore, these fibers can be collected with a magnet for reuse and effectively avoid the secondary pollution of the treated water.

  16. A novel magnetically separable TiO{sub 2}/CoFe{sub 2}O{sub 4} nanofiber with high photocatalytic activity under UV-vis light

    Energy Technology Data Exchange (ETDEWEB)

    Li, Cong-Ju, E-mail: congjuli@gmail.com [Beijing Key Laboratory of Clothing Materials R and D and Assessment, Beijing Institute of Fashion Technology, Beijing 100029 (China); Wang, Jiao-Na; Wang, Bin [Beijing Key Laboratory of Clothing Materials R and D and Assessment, Beijing Institute of Fashion Technology, Beijing 100029 (China); Gong, Jian Ru, E-mail: gongjr@nanoctr.cn [National Center for Nanoscience and Technology, China, 11 Zhongguancun Beiyitiao, Beijing 100190 (China); Lin, Zhang [Fujian Institute of Research on the Structure of Matter, Chinese Academy of Sciences, Fujian 350002 (China)

    2012-02-15

    Graphical abstract: A novel magnetically separable composite photocatalyst TiO{sub 2}/CoFe{sub 2}O{sub 4} nanofiber was prepared by sol-gel method and electrospinning technique, which can be reclaimed with a magnet, and the decolorizing efficiency of MB solution reached 95.87%. Highlights: Black-Right-Pointing-Pointer The composite TiO{sub 2}/CoFe{sub 2}O{sub 4} nanofibers with diameter of 110 {+-} 28 nm have been successfully synthesized by the combination of sol-gel method and electrospinning technique. Black-Right-Pointing-Pointer The presence of Co{sup 2+} or/and Fe{sup 3+} ions may occupy some of the lattice sites of TiO{sub 2} to form an iron-titanium solid solution and narrow the band gap, which broadens the response region of visible light. Black-Right-Pointing-Pointer The resultant nanofibers not only have high decomposition efficiency with methylene blue (MB) under the UV irradiation, which is close to that of Degussa P25, but also can be separated with a magnet and avoid the secondary pollution of the treated water. -- Abstract: A novel magnetically separable heterogeneous photocatalyst TiO{sub 2}/CoFe{sub 2}O{sub 4} nanofiber was prepared by sol-gel method and electrospinning technology, followed by heat treatment at 550 Degree-Sign C for 2 h. The phase structure, morphology and magnetic property of the composite nanofibers were characterized by X-ray diffraction, scanning electron microscopy, transmission electron microscope and vibrating sample magnetometer analysis. The photocatalytic studies of TiO{sub 2}/CoFe{sub 2}O{sub 4} fibers suggested that the presence of CoFe{sub 2}O{sub 4} not only enhanced the absorbance of UV light, but also broadened the response region to visible light. The decolorizing efficiency of methylene blue (MB) solution reaches 95.87% over TiO{sub 2}/CoFe{sub 2}O{sub 4} nanofibers under 300 W Hg lamp after 5 h, which is close to that of Degussa P25. Furthermore, these fibers can be collected with a magnet for reuse and effectively avoid the secondary pollution of the treated water.

  17. Magnetic composite of Fe3O4 and activated carbon as a adsorbent for separation of trace Sr(II) from radioactive wastewater

    International Nuclear Information System (INIS)

    Magnetic adsorbent of Fe3O4 and activated carbon (Fe3O4/AC) was prepared by chemical coprecipitation technique, and was characterized by SEM, TEM, BET, XRD, and VSM techniques in details. The adsorption results of Sr(II) on Fe3O4/AC revealed that Sr(II) adsorption on Fe3O4/AC surface was an spontaneous and endothermic process, and can be well described by the pseudo-second-order model. The adsorption of Sr(II) on Fe3O4/AC increased with increasing pH, and decreased with increasing ionic strength. Fe3O4/AC can be easily separated from aqueous solution with an external magnetic field after application. (author)

  18. Theory of high gradient attractive magnetic separation of superconducting materials and its experimental verification by YBa2Cu3Ox particles

    International Nuclear Information System (INIS)

    The calculation of trajectories for sedimenting diamagnetic particles shows that superconducting matter in the Meissner or vortex state can be captured sidewise to a ferromagnetic wire magnetized perpendicular to its length. Capture is possible for externally applied fields lower than typical critical fields Hc1(c), Hc1(a,b) of cuprates. For single crystalline particles in the vortex state, the magnetic anisotropy may reduce the capture force because of alignment. Theoretical predictions were confirmed experimentally for suspensions of polycrystalline and single crystalline particles of YBa2Cu3Ox (size range: 2-125 ?m) in liquid nitrogen. As a general conclusion we find that for the extraction of superconducting particles out of combinatorial ceramic reaction mixtures, separation in the Meissner state might be most effective because of the presence of an excess of normal state matter featuring a much lower diamagnetic susceptibility

  19. Volume reduction on all particle size of the contaminated soil. Continuous processing technology of attrition, chemical wash under an ambient temperature and pressure condition and magnetic separation

    International Nuclear Information System (INIS)

    An examination was conducted in order to establish a practical purification system that could largely reduce the storage volume of radioactive waste in the Intermediate Storage Facility. The examination consists of a 3-step washing treatment of contaminated soil, which includes “Milling Washing” of removed contaminated soil, chemical extraction of fine soil fraction resulted from the “Milling Washing” under an ambient temperature and pressure condition, and magnetic separation of cesium from the extracted solution. As a result of the examination, we succeeded in development of a safe system with low initial cost and running cost. (author)

  20. A self-consistent two-dimensional resistive fluid theory of field-aligned potential structures including charge separation and magnetic and velocity shear

    Science.gov (United States)

    Hesse, Michael; Birn, Joachim; Schindler, Karl

    1990-01-01

    A self-consistent two-fluid theory that includes the magnetic field and shear patterns is developed to model stationary electrostatic structures with field-aligned potential drops. Shear flow is also included in the theory since this seems to be a prominent feature of the structures of interest. In addition, Ohmic dissipation, a Hall term, and pressure gradients in a generalized Ohm's law, modified for cases without quasi-neutrality, are included. In the analytic theory, the electrostatic force is balanced by field-aligned pressure gradients (i.e., thermal effects in the direction of the magnetic field) and by pressure gradients and magnetic stresses in the perpendicular direction. Within this theory, simple examples of applications are presented to demonstrate the kind of solutions resulting from the model. The results show how the effects of charge separation and shear in the magnetic field and the velocity can be combined to form self-consistent structures such as are found to exist above the aurora, suggested also in association with solar flares.