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1

HTS High Gradient Magnetic Separation system  

SciTech Connect

We report on the assembly, characterization and operation of a high temperature superconducting (HTS) magnetic separator. The magnet is made of 624 m of Silver/BSCCO superconducting wire and has overall dimensions of 18 cm OD, 15.5 cm height and 5 cm ID. The HTS current leads are designed to operate with the warm end at 75 K and the cold end cooled by a two stage Gifford-McMahon cryocooler. The upper stage of the cryocooler cools the thermal shield and two heat pipe thermal intercepts. The lower stage of the cryocooler cools the HTS magnet and the bottom end of the HTS current leads. The HTS magnet was initially characterized in liquid cryogens. We report on the current- voltage (I-V) characteristics of the HTS magnet at temperatures ranging from 15 to 40 K. At 40 K the magnet can generate a central field of 2.0 T at a current of 120 A.

Daugherty, M.A.; Coulter, J.Y.; Hults, W.L. [and others

1996-09-01

2

Development of magnetic separation system of magnetoliposomes  

NASA Astrophysics Data System (ADS)

The magnetic separation technology using sub-microsized ferromagnetic particle is indispensable in many areas of medical biosciences. For example, ferromagnetic particles (200-500 nm) are widely used for cell sorting in stem cell research with the use of cell surface-specific antigens. Nanosized ferromagnetic particles (10-20 nm) have been suggested as more suitable in drug delivery studies given their efficiency of tissue penetration, however, the magnetic separation method for them has not been established. One of the major reasons is that magnetic force acting on the object particles decreases drastically as a particle diameter becomes small. In this study, magnetic force acting on the targets was enhanced by the combination of superconducting magnet and the filter consisting of ferromagnetic particle. By doing so, we confirmed that Fe 3O 4 of 20 nm in diameter was trapped in the magnetic filter under an external magnetic field of 0.5 T. Fe 3O 4 encapsulated with phospholipid liposomes of 200 nm in diameter was also shown to be trapped as external magnetic field of 1.5 T, but not of 0.5 T. We also showed the result of particle trajectory calculation which emulated well the experimental data.

Nakao, R.; Matuo, Y.; Mishima, F.; Taguchi, T.; Maenosono, S.; Nishijima, S.

2009-10-01

3

Development of high gradient magnetic separation system under dry condition  

NASA Astrophysics Data System (ADS)

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.

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

2010-11-01

4

Capture of metallic copper by high gradient magnetic separation system.  

PubMed

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

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

2011-10-01

5

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

NASA Astrophysics Data System (ADS)

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.

Oka, T.; Kanayama, H.; Tanaka, K.; Fukui, S.; Ogawa, J.; Sato, T.; Ooizumi, M.; Terasawa, T.; Itoh, Y.; Yabuno, R.

2009-10-01

6

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

NASA Astrophysics Data System (ADS)

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.

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

2011-11-01

7

Magnetic separation for soil decontamination  

SciTech Connect

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.

Avens, L.R.; Worl, L.A.; deAguero, K.J.; Padilla, D.D.; Prenger, F.C.; Stewart, W.F.; Hill, D.D. [Los Alamos National Lab., NM (United States); Tolt, T.L. [Lockheed Environmental Systems and Technologies (United States)

1993-02-01

8

Magnetic separation for soil decontamination  

SciTech Connect

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.

Avens, L.R.; Worl, L.A.; deAguero, K.J.; Padilla, D.D.; Prenger, F.C.; Stewart, W.F.; Hill, D.D. (Los Alamos National Lab., NM (United States)); Tolt, T.L. (Lockheed Environmental Systems and Technologies (United States))

1993-01-01

9

The use of multifunctional magnetic mesoporous core/shell heteronanostructures in a biomolecule separation system.  

PubMed

A multifunctional magnetic mesoporous core/shell heteronanostructure (designated as Fe(3)O(4)@NiSiO(3)) has been designed and constructed that combined the capacity of effective protein purification from protein mixture and selective low molecule weight (MW) biomolecule enrichment. The nanoparticle is composed by magnetite nanoparticle with immobilized metal ion surface and solid porous shell which presents a number of important features, such as controllable shell thickness, uniform pore size and excellent magnetism. By taking advantages of the high affinity of Ni(2+) on the shell surface toward His-tagged proteins and the fast response toward an assistant magnet, the heteronanoparticles can be applied to selectively bind to and magnetically separate of His-tagged proteins from a cell lysate of E. coli. Additionally, owing to the homogeneous 3D mesopores on the nickel silicate shell, the heteronanoparticles can selectively capture low MW biomolecules from complex mixture. Significantly, it is expected that this approach can be extended to other biomolecule separation and enrichment systems by changing the immobilized surface and the pore size. PMID:21481453

Liu, Zhen; Li, Meng; Yang, Xinjian; Yin, Meili; Ren, Jinsong; Qu, Xiaogang

2011-07-01

10

Separation system  

DOEpatents

A separation system for dewatering radioactive waste materials includes a disposal container, drive structure for receiving the container, and means for releasably attaching the container to the drive structure. Separation structure disposed in the container adjacent the inner surface of the side wall structure retains solids while allowing passage of liquids. Inlet port structure in the container top wall is normally closed by first valve structure that is centrifugally actuated to open the inlet port and discharge port structure at the container periphery receives liquid that passes through the separation structure and is normally closed by second valve structure that is centrifugally actuated to open the discharge ports. The container also includes coupling structure for releasable engagement with the centrifugal drive structure. Centrifugal force produced when the container is driven in rotation by the drive structure opens the valve structures, and radioactive waste material introduced into the container through the open inlet port is dewatered, and the waste is compacted. The ports are automatically closed by the valves when the container drum is not subjected to centrifugal force such that containment effectiveness is enhanced and exposure of personnel to radioactive materials is minimized.

Rubin, Leslie S. (Newton, MA)

1986-01-01

11

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

NASA Astrophysics Data System (ADS)

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.

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

2010-11-01

12

Continuous magnetic separator and process  

DOEpatents

A continuous magnetic separator and process for separating a slurry comprising magnetic particles into a clarified stream and a thickened stream. The separator has a container with a slurry inlet, an overflow outlet for the discharge of the clarified slurry stream, and an underflow outlet for the discharge of a thickened slurry stream. Magnetic particles in the slurry are attracted to, and slide down, magnetic rods within the container. The slurry is thus separated into magnetic concentrate and clarified slurry. Flow control means can be used to control the ratio of the rate of magnetic concentrate to the rate of clarified slurry. Feed control means can be used to control the rate of slurry feed to the slurry inlet.

Oder, Robin R. (Export, PA); Jamison, Russell E. (Lower Burrell, PA)

2008-04-22

13

Superfluidity and quantum vortices in systems with pairing of spatially separated electrons and holes in crossed magnetic and electric fields  

Microsoft Academic Search

The low-temperature behavior of two-dimensional systems with pairing spatially separated electrons and holes is studied. We predict a transition to a superfluid state of a dilute gas of electron-hole pairs in a strong magnetic field normal to conducting layers. In the superfluid phase the crossed electric and magnetic fields are shown to create planar vortices where the pairs rotate in

S. I. Shevchenko

1998-01-01

14

Magnetic separation in water pollution control  

Microsoft Academic Search

Magnetic separation as applied to waterborne contaminants is successful in reducing the solids content of a water sample and in removing the dissolved orthophosphate from the aqueous slurry. The contaminants are chemically associated with a magnetic seeding material, and subsequent removal of this seed sweeps the pollutants from the system. The advantage of this form of treatment over conventional techniques

CHRISTOPHER DE LATOUR

1973-01-01

15

Correspondence between neutron depolarization and higher order magnetic susceptibility to investigate ferromagnetic clusters in phase separated systems.  

PubMed

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

Manna, Kaustuv; Samal, D; Bera, A K; Elizabeth, Suja; Yusuf, S M; Kumar, P S Anil

2014-01-01

16

Separation of magnetic field lines  

SciTech Connect

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 {sigma}, the ratio of the long to the short distance across a cross section of a flux tube characteristically increases by e{sup 2{sigma}}, and the ratio of the longer distance to the initial radius increases as e{sup {sigma}}. Electron inertia prevents a plasma from isolating two magnetic field structures on a distance scale shorter than c/{omega}{sub pe}, which is about 10 cm in the solar corona, and reconnection must be triggered if {sigma} becomes sufficiently large. The radius of the sun, R{sub Circled-Dot-Operator }=7 Multiplication-Sign 10{sup 10}cm is about e{sup 23} times larger, so when {sigma} Greater-Than-Or-Equivalent-To 23, two lines separated by c/{omega}{sub 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, {sigma}, are derived, and the importance of exponentiation is discussed.

Boozer, Allen H. [Department of Applied Physics and Applied Mathematics, Columbia University, New York, New York 10027 (United States)

2012-11-15

17

Development of an aptamer-based impedimetric bioassay using microfluidic system and magnetic separation for protein detection.  

PubMed

An aptamer-based impedimetric bioassay using the microfluidic system and magnetic separation was developed for the sensitive and rapid detection of protein. The microfluidic impedance device was fabricated through integrating the gold interdigitated array microelectrode into a flow cell made of polydimethylsiloxane (PDMS). Aptamer modified magnetic beads were used to capture and separate the target protein, and concentrated into a suitable volume. Then the complexes were injected into the microfluidic flow cell for impedance measurement. To demonstrate the high performance of this novel detection system, thrombin was employed as the target protein. The results showed that the impedance signals at the frequency of 90 kHz have a good linearity with the concentrations of thrombin in a range from 0.1 nM to 10nM and the detection limit is 0.01 nM. Compared with the reported impedimetric aptasensors for thrombin detection, this method possesses several advantages, such as the increasing sensitivity, improving reproducibility, reducing sample volume and assay time. All these demonstrate the proposed detection system is an alternative way to enable sensitive, rapid and specific detection of protein. PMID:24709326

Wang, Yixian; Ye, Zunzhong; Ping, Jianfeng; Jing, Shunru; Ying, Yibin

2014-09-15

18

Multistage Magnetic Separator of Cells and Proteins  

NASA Technical Reports Server (NTRS)

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.

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

2005-01-01

19

The design of the drum separator with superconducting magnets  

SciTech Connect

This paper describes the open gradient drum type magnetic separator with superconducting magnet system to develop technologies for dry separation of low magnetic mineral raw material of 4-0 mm (medium size) up to 25-0 mm (coarse size). The separation zone is 1200 mm x 50 mm with the magnet system-wrap angle equal to 90{degree}, the magnetic field in the separation zone is at the level of 4.5 T, the average value of the magnetic forces is 120 T{sup 2}/m and the capacity is about 100 t/h. The results of the optimization and numerical calculations of thermophysical processes in magnetic and cryogenic systems are given. The technological developments of the design of some separator units are presented. The paper also presents the techno-economic indices of the separator application at the ore-mining operations.

Sidorenko, V.D.; Gerasimenko, I.A.; Kretinin, E.A. [Mekhanobrchermet Inst., Krivoy Rog (Ukraine). Lab. for Superconducting Technique and Technologies] [Mekhanobrchermet Inst., Krivoy Rog (Ukraine). Lab. for Superconducting Technique and Technologies; Zhelamsky, M.V.; Bondarchuk, E.N.; Rodin, I.Y.; Muratov, V.P. [Scientific and Research Inst. of Electrophysical Apparatus, St. Petersburg (Russian Federation)] [Scientific and Research Inst. of Electrophysical Apparatus, St. Petersburg (Russian Federation)

1996-07-01

20

Magnetic Separator Enhances Treatment Possibilities  

NASA Technical Reports Server (NTRS)

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.

2008-01-01

21

Magnetic micro-devices for separation and manipulation of biological components.  

E-print Network

??A scheme for magnetic based biomolecular separation, transportation and detection has been proposed, designed, fabricated and successfully demonstrated through a novel micro-fabricated magnetic system. Magnetic… (more)

Qasem Ramadan.

2008-01-01

22

Rotary drum separator system  

NASA Technical Reports Server (NTRS)

A rotary phase separator system generally includes a step-shaped rotary drum separator (RDS) and a motor assembly. The aspect ratio of the stepped drum minimizes power for both the accumulating and pumping functions. The accumulator section of the RDS has a relatively small diameter to minimize power losses within an axial length to define significant volume for accumulation. The pumping section of the RDS has a larger diameter to increase pumping head but has a shorter axial length to minimize power losses. The motor assembly drives the RDS at a low speed for separating and accumulating and a higher speed for pumping.

Barone, Michael R. (Inventor); Murdoch, Karen (Inventor); Scull, Timothy D. (Inventor); Fort, James H. (Inventor)

2009-01-01

23

Continuous cell separation using novel magnetic quadrupole flow sorter  

Microsoft Academic Search

A laboratory prototype of a flow cell sorter based on magnetic quadrupole field was built and evaluated. The magnetic force acting on magnetically labeled cells in such a field has a `centrifugal’ character which provides a basis for the design of a continuous separation process. The sorter was tested on a model cell system of human peripheral lymphocytes labeled with

Maciej Zborowski; Liping Sun; Lee R Moore; P Stephen Williams; Jeffrey J. Chalmers

1999-01-01

24

Magnetic separation of micro-spheres from viscous biological fluids.  

SciTech Connect

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.

Chen, H.; Kaminski, M. D.; Xianqiao, L.; Caviness, P.; Torno, M.; Rosengart, A. J.; Dhar, P.; Chemical Engineering; Univ. of Chicago Pritzker School of Medicine; Illinois Inst. of Tech.

2007-02-21

25

Particle acceleration at a reconnecting magnetic separator  

E-print Network

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 ...

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

2014-01-01

26

Magnetic separation techniques in diagnostic microbiology.  

PubMed

The principles of magnetic separation aided by antibodies or other specific binding molecules have been used for isolation of specific viable whole organisms, antigens, or nucleic acids. Whereas growth on selective media may be helpful in isolation of a certain bacterial species, immunomagnetic separation (IMS) technology can isolate strains possessing specific and characteristic surface antigens. Further separation, cultivation, and identification of the isolate can be performed by traditional biochemical, immunologic, or molecular methods. PCR can be used for amplification and identification of genes of diagnostic importance for a target organism. The combination of IMS and PCR reduces the assay time to several hours while increasing both specificity and sensitivity. Use of streptavidin-coated magnetic beads for separation of amplified DNA fragments, containing both biotin and a signal molecule, has allowed for the conversion of the traditional PCR into an easy-to-read microtiter plate format. The bead-bound PCR amplicons can also easily be sequenced in an automated DNA sequencer. The latter technique makes it possible to obtain sequence data of 300 to 600 bases from 20 to 30 strains, starting with clinical samples, within 12 to 24 h. Sequence data can be used for both diagnostic and epidemiologic purposes. IMS has been demonstrated to be a useful method in diagnostic microbiology. Most recent publications describe IMS as a method for enhancing the specificity and sensitivity of other detection systems, such as PCR, and providing considerable savings in time compared with traditional diagnostic systems. The relevance to clinical diagnosis has, however, not yet been fully established for all of these new test principles. In the case of PCR, for example, the presence of specific DNA in a food sample does not demonstrate the presence of a live organism capable of inducing a disease. However, all tests offering increased sensitivity and specificity of detection, combined with reduced time of analysis, have to be seriously evaluated. PMID:8118790

Olsvik, O; Popovic, T; Skjerve, E; Cudjoe, K S; Hornes, E; Ugelstad, J; Uhlén, M

1994-01-01

27

Design of a core-shell type immuno-magnetic separation system and multiplex PCR for rapid detection of pathogens from food samples.  

PubMed

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

Ozalp, V Cengiz; Bayramoglu, Gulay; Arica, M Yakup; Oktem, H Avni

2013-11-01

28

Magnetic aqueous two-phase separation in preparative applications.  

PubMed

Magnetic aqueous two-phase separation is a new technique to speed up the separation of aqueous two-phase systems (Anal. Biochem. 1987, 167, 331-339). It is based on the addition of magnetically susceptible material (e.g. 1-micron iron oxide particles) which induces rapid phase separation when a mixed system is placed in a magnetic field. The technique has been applied to a number of two-phase systems. The time for phase separation was decreased by a factor of 5-240,000, with the largest improvement for systems containing high concentrations of protein and for systems with viscous or nearly isopycnic phases. An apparatus for preparative multistage extraction with magnetic separation was constructed and tested on glycolytic enzymes present in a yeast extract using a dextran/Cibacron blue-polyethylene glycol system. The presence of iron oxide particles did not adversely affect the extracted enzymes. An electromagnet-based apparatus for continuous phase separation on a larger scale was also designed. A phase system containing crude dextran and unpurified cell homogenate was effectively processed. The apparatus also allowed effective separation when the phase containing iron oxide particles was only a small fraction (4%) of the total phase system. PMID:1368542

Flygare, S; Wikström, P; Johansson, G; Larsson, P O

1990-02-01

29

Magnetic-based microfluidic platform for biomolecular separation.  

PubMed

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

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

2006-06-01

30

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

Microsoft Academic Search

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

Yiran Li; Jun Wang; Xiaojun Wang; Baoqiang Wang; Zhaokun Luan

2011-01-01

31

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

PubMed Central

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 predictions for high gradient magnetic systems. On the basis of these findings we suggest that ferritin conjugated ligands can be used for selective magnetic separation of labeled cells. Images FIGURE 2 PMID:6743752

Odette, L L; McCloskey, M A; Young, S H

1984-01-01

32

Dual Magnetic Separator for TRI$?$P  

E-print Network

The TRI$\\mu$P facility, under construction at KVI, requires the production and separation of short-lived and rare isotopes. Direct reactions, fragmentation and fusion-evaporation reactions in normal and inverse kinematics are foreseen to produce nuclides of interest with a variety of heavy-ion beams from the superconducting cyclotron AGOR. For this purpose, we have designed, constructed and commissioned a versatile magnetic separator that allows efficient injection into an ion catcher, i.e., gas-filled stopper/cooler or thermal ionizer, from which a low energy radioactive beam will be extracted. The separator performance was tested with the production and clean separation of $^{21}$Na ions, where a beam purity of 99.5% could be achieved. For fusion-evaporation products, some of the features of its operation as a gas-filled recoil separator were tested.

G. P. A. Berg; O. C. Dermois; U. Dammalapati; P. Dendooven M. N. Harakeh; K. Jungmann; C. J. G. Onderwater; A. Rogachevskiy; M. Sohani; E. Traykov; L. Willmann; H. W. Wilschut

2005-09-09

33

Plasma separation from magnetic field lines in a magnetic nozzle  

NASA Technical Reports Server (NTRS)

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.

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

1993-01-01

34

New separators for battery systems  

Microsoft Academic Search

The reported study takes into consideration separators for miniature cells, such as silver\\/zinc button cells, and separators for aircraft nickel\\/cadmium batteries. It is pointed out that separators for energy systems having an aqueous electrolyte, either acid or basic, can be prepared by selective modification of radiation grafting parameters. A new family of separators, known as the 'SC' series, has been

J. Lee; V. Dagostino

1981-01-01

35

Haloing in bimodal magnetic colloids: the role of field induced phase separation , P.Kuzhir1  

E-print Network

separation, ferrofluid, magnetic colloids Abstract If a suspension of magnetic micron-sized and nano1 Haloing in bimodal magnetic colloids: the role of field induced phase separation C.Magnet1 , P technologies used in bio-analysis and water purification systems. 1. Introduction Bimodal colloidal mixtures

Boyer, Edmond

36

O-Allylation of phenols with allylic acetates in aqueous media using a magnetically separable catalytic system  

EPA Science Inventory

Allylic ethers were synthesized in water using magnetically recoverable heterogeneous Pd catalyst via O-allylation of phenols with allylic acetates under ambient conditions. Aqueous reaction medium, easy recovery of the catalyst using an external magnet, efficient recycling, and ...

37

Magnetically-Separable and Highly-Stable Enzyme System Based on Crosslinked Enzyme Aggregates Shipped in Magnetite-Coated Mesoporous Silica  

SciTech Connect

Magnetically-separable and highly-stable enzyme system was developed by adsorption of enzymes in superparamagnetic hierarchically ordered mesocellular mesoporous silica (M-HMMS) and subsequent enzyme crosslinking. Superparamagnetic nanoparticles were homogeneously incorporated into hierarchically-ordered mesocellular mesoporous silica (HMMS) by the decomposition of preformed iron propionate complex. The size of incorporated superparamagnetic 15 nanoparticles was around 5 nm, generating a magnetically separable host with high pore volumes and large pores (M-HMMS). ?-chymotrypsin (CT) was adsorbed into M-HMMS with high loading (~30 wt%) in less than 30 minutes. Glutaraldehyde (GA) treatment of adsorbed CT resulted in nanometer scale crosslinked enzyme aggregates in M-HMMS (CLEA-M). The activity of these CT aggregates in M-HMMS (CLEA-M-CT) was 34 times than that of simply adsorbed CT in M20 HMMS, due to an effective prevention of enzyme leaching during washing via a ship-in-a-bottle approach. CLEA-M-CT maintained the intial activity not only under shaking (250 rpm) for 30 days, but also under recycled uses of 35 times. The same approach was employed for the synthesis of CLEA-M of lipase (CLEA-M-LP), and proven to be effective in improving the loading, activity, and stability of enzyme when compared to those of adsorbed LP in M-HMMS.

Lee, Jinwoo; Na, Hyon Bin; Kim, Byoung Chan; Lee, Jin Hyung; Lee, Byoungsoo; Kwak, Ja Hun; Hwang, Yosun; Park, Je-Geun; Gu, Man Bock; Kim, Jaeyun; Joo, Jin; Shin, Chae-Ho; Grate, Jay W.; Hyeon, Taeghwan; Kim, Jungbae

2009-10-15

38

Electron spin separation without magnetic field.  

PubMed

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

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

2014-08-27

39

Investigation of open-gradient magnetic separation for Illinois coal  

SciTech Connect

Open-gradient magnetic separation (OGMS) using superconducting quadrupole magnets is a novel coal-beneficiation technology offering high pyritic-sulfur removal from pulverized dry coal. The system operates in a continuous mode, uses no chemicals, and has an estimated power demand 75% lower than techniques using conventional electromagnets, while achieving magnetic separation forces up to 267% higher. Specifically applicable to finely ground coal (120 to 325 mesh), OGMS could encourage the commercialization of other developing coal technologies, such as coal-water slurries, fludized-bed combustion, and coal synfuels. Both the experimental program conducted by Argonne National Laboratory and the results of modeling in support of the experimental program are described. 11 refs., 9 figs.

Doctor, R.D.; Livengood, C.D.; Genens, L.E.; Swietlik, C.E.; Foote, K.

1987-01-01

40

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

PubMed

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

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

2010-08-01

41

Fundamental study on magnetic separation of aquatic organisms for preservation of marine ecosystem  

NASA Astrophysics Data System (ADS)

Recently, destruction and disturbance of marine ecosystem have been caused by changes in global environment and transplants of farmed fishes and shellfishes. To solve the problems, water treatment techniques to kill or to remove aquatic organisms are necessary. In this study, application of magnetic separation for removal of the aquatic organisms was examined in order to establish the process with high-speed, compact device and low environmental load. Techniques of magnetic seeding and magnetic separation using superconducting magnet are important for high-speed processing of aquatic organisms. Magnetic seeding is to adhere separating object to the surface of ferromagnetic particles, and magnetic separation is to remove aquatic organisms with magnetic force. First, we confirmed the possibility of magnetic seeding of aquatic organisms, and then interaction between aquatic organisms and ferromagnetic particles was examined. Next, for practical application of magnetic separation system using superconducting magnet for removal of aquatic organisms, particle trajectories were simulated and magnetic separation experiment using superconducting magnet was performed in order to design magnetic separation system to achieve high separation efficiency.

Sakaguchi, F.; Akiyama, Y.; Izumi, Y.; Nishijima, S.

2009-10-01

42

Differential magnetic catch and release: experimental parameters for controlled separation of magnetic nanoparticles.  

PubMed

Differential magnetic catch and release (DMCR) has been used as a method for the purification and separation of magnetic nanoparticles. DMCR separates nanoparticles in the mobile phase by magnetic trapping of magnetic nanoparticles against the wall of an open tubular capillary wrapped between two narrowly spaced electromagnetic poles. Using Au and CoFe(2)O(4) nanoparticles as model systems, the loading capacity of the 250 ?m diameter capillary is determined to be ?130 ?g, and is scalable to higher quantities with larger bore capillary. Peak resolution in DMCR is externally controlled by selection of the release time (R(t)) at which the magnetic flux density is removed, however, longer capture times are shown to reduce the capture yield. In addition, the magnetic nanoparticle capture yields are observed to depend on the nanoparticle diameter, mobile phase viscosity and velocity, and applied magnetic flux. Using these optimized parameters, three samples of CoFe(2)O(4) nanoparticles whose diameters are different by less than 10 nm are separated with excellent resolution and capture yield, demonstrating the capability of DMCR for separation and purification of magnetic nanoparticles. PMID:21562675

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

2011-06-21

43

Noise suppressing capillary separation system  

DOEpatents

A noise-suppressing capillary separation system for detecting the real-time presence or concentration of an analyte in a sample is provided. The system contains a capillary separation means through which the analyte is moved, a coherent light source that generates a beam which is split into a reference beam and a sample beam that irradiate the capillary, and a detector for detecting the reference beam and the sample beam light that transmits through the capillary. The laser beam is of a wavelength effective to be absorbed by a chromophore in the capillary. The system includes a noise suppressing system to improve performance and accuracy without signal averaging or multiple scans.

Yeung, Edward S. (Ames, IA); Xue, Yongjun (Norwich, NY)

1996-07-30

44

On Power System Controlled Separation  

Microsoft Academic Search

This paper describes verification of five conjectures related to power system controlled separation. It attempts to verify that the location of uncontrolled separation (loss of synchronism or out-of-step operation) is independent of the location and severity (short-circuit duty or duration) of the initial faults, that the location depends on the prevailing network configuration and load level, and that it takes

M. M. Adibi; R. J. Kafka; Sandeep Maram; Lamine M. Mili

2006-01-01

45

Controlled Separation of Power Systems  

Microsoft Academic Search

Transmission lines are subject to internal and external faults. The internal faults are rapidly cleared leaving the power system in an un-faulted condition. However, they cause an imbalance between the generators' mechanical input and electrical output producing external faults that in turn separate the power system into imbalanced load and generation islands and consequently result in blackouts.

M. M. Adibi

2007-01-01

46

PROCESSING EQUIPMENT FOR RESOURCE RECOVERY SYSTEMS. VOLUME II. MAGNETIC SEPARATORS, AIR CLASSIFIER AND AMBIENT AIR EMISSIONS TESTS  

EPA Science Inventory

This report presents the results of a study of equipment and systems for processing municipal solid wastes into energy related products. The study was divided into three phases. The first phase was devoted to a study of the state of the art and formulation of the research needs. ...

47

Study on magnetic separation of nanosized ferromagnetic particles  

NASA Astrophysics Data System (ADS)

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.

Nakao, R.; Matuo, Y.; Mishima, F.; Taguchi, T.; Nishijima, S.

2009-03-01

48

Fundamental study of phosphor separation by controlling magnetic force  

NASA Astrophysics Data System (ADS)

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.

Wada, Kohei; Mishima, Fumihito; Akiyama, Yoko; Nishijima, Shigehiro

2013-11-01

49

Microfluidic high gradient magnetic cell separation David W. Inglisa  

E-print Network

and by the selective attachment of magnetic beads has recently been demonstrated on microfluidic devices. We discuss is performed nearly every time blood is extracted from the body. In a centrifuge blood is separated along divided into two classes: using magnetic beads to select cell types, and using the native magnetic

50

Operating characteristics of superconducting high gradient magnetic separators  

Microsoft Academic Search

An 84 in. warm bore or operating bore superconducting high gradient magnetic separator has been designed and has been operational since May, 1986. It is used to process clay to improve its brightness. Since the magnetic force is proportional to the product of flux density and gradient, the included canister is packed with magnetic stainless steel wool. The effect of

J. A. Selvaggi

1989-01-01

51

Magnetic propulsion systems  

Microsoft Academic Search

Magnetic propulsion systems are based on the direct interaction of the vehicle's own magnetic field with the natural magnetic field, particularly the geomagnetic one, without using jet propulsion. Three such systems are reviewed in the order of their feasibility of automatic control over the thrust force vector. One of these magnetic propulsion systems permits partial control and is competitive with

Valentine Pulatov

2001-01-01

52

Magnetic Resonance Imaging System Based on Earth's Magnetic Field  

Microsoft Academic Search

This article describes both the setup and the use of a system for magnetic resonance imaging (MRI) in the Earth's magnetic field. Phase instability caused by temporal fluctuations of Earth's field can be successfully improved by using a reference signal from a separate Earth's field nuclear magnetic resonance (NMR) spectrometer\\/magnetometer. In imaging, it is important to correctly determine the phase

Ales Mohoric; Gorazd Planinsic; Miha Kos; Andrej Duh; Janez Stepisnik

2004-01-01

53

Magnetically activated micromixers for separation membranes.  

PubMed

Presented here is a radically novel approach to reduce concentration polarization and, potentially, also fouling by colloids present in aqueous feeds: magnetically responsive micromixing membranes. Hydrophilic polymer chains, poly(2-hydroxyethyl methacrylate) (PHEMA), were grafted via controlled surface-initiated atom transfer radical polymerization (SI-ATRP) on the surface of polyamide composite nanofiltration (NF) membranes and then end-capped with superparamagnetic iron oxide magnetite (Fe(3)O(4)) nanoparticles. The results of all functionalization steps, that is, bromide ATRP initiator immobilization, SI-ATRP, conversion of PHEMA end groups from bromide to amine, and carboxyl-functional Fe(3)O(4) nanoparticle immobilization via peptide coupling, have been confirmed by X-ray photoelectron spectroscopy (XPS) and field emission scanning electron microscopy (FESEM). These nanoparticles experience a magnetic force as well as a torque under an oscillating external magnetic field. It has been shown, using particle image velocimetry (PIV), that the resulting movement of the polymer brushes at certain magnetic field frequencies induces mixing directly above the membrane surface. Furthermore, it was demonstrated that with such membranes the NF performance could significantly be improved (increase of flux and salt rejection) by an oscillating magnetic field, which can be explained by a reduced concentration polarization in the boundary layer. However, the proof-of-concept presented here for the active alteration of macroscopic flow via surface-anchored micromixers based on polymer-nanoparticle conjugates has much broader implications. PMID:21462955

Himstedt, Heath H; Yang, Qian; Dasi, L Prasad; Qian, Xianghong; Wickramasinghe, S Ranil; Ulbricht, Mathias

2011-05-01

54

Emerging magnetism and electronic phase separation at titanate interfaces  

NASA Astrophysics Data System (ADS)

The emergence of magnetism in otherwise nonmagnetic compounds and its underlying mechanisms have become the subject of intense research. Here we demonstrate that the nonmagnetic oxygen vacancies are responsible for an unconventional magnetic state common for titanate interfaces and surfaces. Using an effective multiorbital modeling, we find that the presence of localized vacancies leads to an interplay of ferromagnetic order in the itinerant t2g band and complex magnetic oscillations in the orbitally reconstructed eg band, which can be tuned by gate fields at oxide interfaces. The magnetic phase diagram includes highly fragmented regions of stable and phase-separated magnetic states forming beyond nonzero critical defect concentrations.

Pavlenko, N.; Kopp, T.; Mannhart, J.

2013-11-01

55

Physical separation of particles in magnetized fluidized beds  

Microsoft Academic Search

Magnetized fluidized bed stability is defined using relative amplitudes of pressure fluctuations. It is shown that transition velocities exist for different degrees of bed stability. Experimental results show that magnetically stabilized fluidized beds can be used to effect separation of particles by differences in particle penetration depth and settling velocity.

O. Harel; W. Resnick; Y. Zimmels

1990-01-01

56

Apparatus and method for continuous separation of magnetic particles from non-magnetic fluids  

DOEpatents

A magnetic separator vessel (1) for separating magnetic particles from non-magnetic fluid includes a separation chamber having an interior and exterior wall, a top and bottom portion; a magnet (3) having first and second poles (2) positioned adjacent to the exterior wall, wherein the first pole is substantially diametrically opposed to the second pole; a inlet port (5) is directed into the top portion of the separation chamber, wherein the inlet port (5) is positioned adjacent to one of the first and second poles (2), wherein the inlet port (5) is adapted to transfer a mixture into the separation chamber; an underflow port (6) in communication with the bottom portion, wherein the underflow port (6) is adapted to receive the magnetic particles; and an overflow port (9) in communication with the separation chamber, wherein the overflow port (9) is adapted to receive the non-magnetic fluid.

Oder, Robin R. (Export, PA); Jamison, Russell E. (Lower Burrell, PA)

2010-02-09

57

Large gap magnetic suspension system  

NASA Technical Reports Server (NTRS)

The design of a large gap magnetic suspension system is discussed. Some of the topics covered include: the system configuration, permanent magnet material, levitation magnet system, superconducting magnets, resistive magnets, superconducting levitation coils, resistive levitation coils, levitation magnet system, and the nitrogen cooled magnet system.

Abdelsalam, Moustafa K.; Eyssa, Y. M.

1991-01-01

58

Rare Cell Separation and Analysis by Magnetic Sorting  

PubMed Central

Summary 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 cells. PMID:21812408

Zborowski, Maciej; Chalmers, Jeffrey J.

2011-01-01

59

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

NASA Astrophysics Data System (ADS)

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.

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

2014-07-01

60

Simulation of recoil trajectories in gas-filled magnetic separators  

NASA Astrophysics Data System (ADS)

A computer code has been developed to simulate the production of heavy element compound nucleus recoils and their trajectories through gas-filled magnetic separators. The simulation is carried out in three steps: positions and trajectories of heavy element recoils in the target layer, propagation through remaining target material, and trajectories through the gas-filled separator. Separators with quite different magnetic configurations are modeled: the Berkeley gas-filled separator (BGS) and two magnetic configurations for the TransActinide separator and chemistry apparatus (TASCA). While computing trajectories through the gas-filled separator, special attention is paid to the charge exchange/equilibration and scattering in the gas. New features of these simulations include mixed He/H2/N2 gas operation and a gas density (pressure) effect. Numerical procedures used in the simulations are explained in detail. Results of the simulations are presented, showing the gas mixtures/pressures that result in the highest efficiency for collecting compound nucleus recoils at the focal plane of the gas-filled separator. Comparison between simulation and experimental results are presented for average recoil ion charge in various gases, focal plane image size, and magnetic rigidity dispersion.

Gregorich, K. E.

2013-05-01

61

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

NASA Astrophysics Data System (ADS)

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.

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

2014-01-01

62

Waste remediation using in situ magnetically assisted chemical separation  

SciTech Connect

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.

Nunez, L.; Buchholz, B.A.; Vandegrift, G.F.

1993-11-01

63

Modeling high gradient magnetic separation from biological fluids.  

SciTech Connect

A proposed portable magnetic separator consists of an array of biocompatible capillary tubing and magnetizable wires immersed in an externally applied homogeneous magnetic field. While subject to the homogeneous magnetic field, the wires create high magnetic field gradients, which aid in the collection of blood-borne magnetic nanospheres from blood flow. In this study, a 3-D numerical model was created using COMSOL Multiphysics 3.2 software to determine the configuration of the wire-tubing array from two possible configurations, one being an array with rows alternating between wires and tubing, and the other being an array where wire and tubing alternate in two directions. The results demonstrated that the second configuration would actually capture more of the magnetic spheres. Experimental data obtained by our group support this numerical result.

Bockenfeld, D.; Chen, H.; Rempfer, D.; Kaminski, M. D.; Rosengart, A. J.; Chemical Engineering; Illinois Inst. of Tech.; Univ. of Chicago, Pritzker School of Medicine

2006-01-01

64

Inverted Linear Halbach Array for Separation of Magnetic Nanoparticles  

PubMed Central

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.

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

2014-01-01

65

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

NASA Astrophysics Data System (ADS)

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.

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

2012-10-01

66

Process to remove actinides from soil using magnetic separation  

DOEpatents

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.

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

67

Separation of feeble magnetic particles with magneto-Archimedes levitation  

Microsoft Academic Search

Particles and solid substances with feeble magnetic susceptibility were levitated by magnetic fields with the aid of the “magneto-Archimedes levitation” method [Nature 393 (1998) 749]. A novel feature was found, namely that the initial particle mixture levitated underwent separation into each kind of the ingredient particle aggregates. The samples levitated were NaCl–KCl grain mixtures, and colored glass particles. The experiments

Y Ikezoe; T Kaihatsu; S Sakae; H Uetake; N Hirota; K Kitazawa

2002-01-01

68

Effect of reverse flotation on magnetic separation concentrates  

NASA Astrophysics Data System (ADS)

Reverse flotation studies on magnetite samples have revealed that the use of starch as a depressant of Fe-oxides has a hydrophilic effect on the surface of Fe-bearing silicates and significantly decreases Fe in the silica-rich stream when used in combination with an amine (Lilaflot D817M). In this study, the effect of reverse flotation on the optimization of products obtained from magnetic separation was investigated. Two different magnetic samples, zones 1 and 2, were milled to <75 ?m and then subjected to low intensity magnetic separation (LIMS). The LIMS test conducted on the <75 ?m shown an upgrade of 46.40wt% Fe, 28.40wt% SiO2 and 2.61wt% MnO for zone 1 and 47.60wt% Fe, 29.17wt% SiO2 and 0.50wt% MnO for zone 2. Further milling of the ore to <25 ?m resulted in a higher magnetic-rich product after magnetic separation. Reverse flotation tests were conducted on the agitated magnetic concentrate feed, and the result shows a significant upgrade of Fe compared to that obtained from the non-agitated feed. Iron concentrations greater than 69%, and SiO2 concentrations less than 2% with overall magnetite recoveries greater than 67% and 71% were obtained for zones 1 and 2, respectively.

Bada, S. O.; Afolabi, A. S.; Makhula, M. J.

2012-08-01

69

What Defines a Separate Hydrothermal System  

SciTech Connect

Separate hydrothermal systems can be defined in a variety of ways. Criteria which have been applied include separation of heat source, upflow, economic resource and geophysical anomaly. Alternatively, connections have been defined by the effects of withdrawal of economically useful fluid and subsidence, effects of reinjection, changes in thermal features, or by a hydrological connection of groundwaters. It is proposed here that: ''A separate hydrothermal system is one that is fed by a separate convective upflow of fluid, at a depth above the brittle-ductile transition for the host rocks, while acknowledging that separate hydrothermal systems can be hydrologically interconnected at shallower levels''.

Lawless, J.V.; Bogie, I.; Bignall, G.

1995-01-01

70

New separators for battery systems  

SciTech Connect

Batteries convert the energy of chemical reactions into electrical energy. Since this conversion is not Carnot-limited, the thermodynamic efficiency can be higher than that of a thermal power plant. This paper deals with separators for miniature cells like Silver/Zinc button cells, for chargeable batteries like aircraft Nickel/Cadmium batteries, and for others under evaluation. 4 refs.

Lee, J.; D'Agostino, V.

1981-01-01

71

TPC magnet cryogenic system  

SciTech Connect

The Time Projection Chamber (TPC) magnet at LBL and its compensation solenoids are adiabatically stable superconducting solenoid magnets. The cryogenic system developed for the TPC magnet is discussed. This system uses forced two-phase tubular cooling with the two cryogens in the system. The liquid helium and liquid nitrogen are delivered through the cooled load by forced tubular flow. The only reservoirs of liquid cryogen exist in the control dewar (for liquid helium) and the conditioner dewar (for liquid nitrogen). The operation o these systems during virtually all phases of system operation are described. Photographs and diagrams of various system components are shown, and cryogenic system data are presented in the following sections: (1) heat leaks into the TPC coil package and the compensation solenoids; (2) heat leaks to various components of the TPC magnet cryogenics system besides the magnets and control dewar; (3) the control dewar and its relationship to the rest of the system; (4) the conditioner system and its role in cooling down the TPC magnet; (5) gas-cooled electrical leads and charging losses; and (6) a summation of the liquid helium and liquid nitrogen requirements for the TPC superconducting magnet system.

Green, M.A.; Burns, W.A.; Taylor, J.D.; Van Slyke, H.W.

1980-03-01

72

Coil geometry for efficient active compensation with separated magnetic shields  

NASA Astrophysics Data System (ADS)

We have already proposed a new method of magnetic shielding aiming for magnetocardiography, in which magnetic shells are separated and a new compensation scheme is employed to allow for wide space between them. Each magnetic shell that consists of a half of the cylinder (diameter=20 cm and length=60 cm) and two flanges at both ends of the half cylinder extending along the radial direction has a saddle coil on its outer surface with the coil's long straight section running parallel to the axis of the cylinder. In this paper, the relationship between the width of the long straight sections of the saddle coil and the efficiency of the active compensation is investigated by the finite element method (FEM) analysis and by experiments. A magnetic shield used in this study is a double shell structure where each shell is made of stacked amorphous tapes and the outer shell has a magnetic shaking coil for the enhancement of the permeability. We have found that for a given magnetic field, the compensation current necessary for a given magnetic field varies by a factor of 3 depending on the width of a saddle coil and that its value monotonically decreases with increasing the width. We have also confirmed that the phase delay of the compensation magnetic field experienced while it comes in the magnetic shell is small.

Nakashima, Yoshihiro; Sasada, Ichiro

2009-04-01

73

TREATMENT OF COMBINED SEWER OVERFLOWS BY HIGH GRADIENT MAGNETIC SEPARATION  

EPA Science Inventory

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...

74

Purification of Wastewater From Paper Factory by Superconducting Magnetic Separation  

Microsoft Academic Search

It is environmentally important to recycle the wastewater, since paper factories use a large amount of water and equivalent amount of wastewater is generated. Conventional water treatment facilities like precipitation process need large-scale equipment and wide space to purify the wastewater of paper factory. In case of massive waste water, high gradient magnetic separation (HGMS) parts are more effective to

Dong-Woo Ha; Tae-Hyung Kim; Myung-Hwan Sohn; Jun-Mo Kwon; Seung-Kyu Baik; Rock-Kil Ko; Sang-Soo Oh; Hong-Soo Ha; Ho-Sup Kim; Young-Hun Kim; Tae-Wook Ha

2010-01-01

75

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

E-print Network

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...

Eisenträger, Almut; Griffiths, Ian M

2014-01-01

76

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

NASA Astrophysics Data System (ADS)

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.

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

2011-11-01

77

Upgrading mixed polyolefin waste with magnetic density separation.  

PubMed

Polyolefin fractions are often end fractions resulting from the recycling of end-of-life consumer products. Polypropylene (PP) and polyethylene (PE) are present in such fractions as a mixture. For instance, the ratio of PP and PE in car scrap is 70:30 on average. However, the grade of the PP and PE should typically be better than 97% to be reused again as a high quality product. Density separation of the different polyolefins can be a solution. A promising separation technique is the inverse magnetic density separator (IMDS). This paper discusses the potential of shredder residue, one of the possible polyolefin's waste stream sources for the IMDS, in detail. Experiments with the separation of polyolefins with an IMDS prototype show both high grade and high recovery. The paper concludes with the economic opportunities of the IMDS in the recycling of polyolefins. PMID:19128952

Bakker, E J; Rem, P C; Fraunholcz, N

2009-05-01

78

[Development of new magnetic bead separation and purification instrument].  

PubMed

The article describes the development of new magnetic bead separation and purification instrument. The main application of the instrument is to capture tubercle bacillus from sputum. It is a pretreatment instrument and provides a new platform to help doctors to diagnose bacillary phthisis. Not only could it be used for tubercle bacillus capturing, but also for gene, protein and cell separating and purification. Because the controller of the instrument is 16-bit single chip microcomputer, the cost could be greatly reduced and it will be widely used in China. PMID:25241516

Xu, Yingyuan; Chen, Yi

2014-05-01

79

Oil-field wastewater purification by magnetic separation technique using a novel magnetic nanoparticle  

NASA Astrophysics Data System (ADS)

In the present work, oil-field wastewater purification through superconducting magnetic separation technique using a novel magnetic nanoparticle was investigated. The magnetic nanoparticle, which has a multi-shell structure with ferroferric oxide as core, dense nonporous silica as inter layer and mesoporous silica as outer layer, was synthesized by co-precipitation method. To functionalize the magnetic nanoparticle, plasma polymerization technique was adopted and poly methyl acrylate (PMA) was formed on the surface of the nanoparticle. The multi-shell structure of the nanoparticle was confirmed by transmission electron microscope (TEM) and the characteristic is measurable by FTIR. It is found that most of the pollutants (85% by turbidity or 84% by COD value) in the oil-field wastewater are removed through the superconducting magnetic separation technique using this novel magnetic nanoparticle.

Liu, Zhuonan; Yang, Huihui; Zhang, Hao; Huang, Chuanjun; Li, Laifeng

2012-12-01

80

Magnetic Separation for Nuclear Material Detection and Surveillance  

SciTech Connect

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 0.8{micro}m PuO{sub 2} 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.

Worl, L.A.; Devlin, D.; Hill, D.; Padilla, D.; Prenger, F.C.

1998-08-01

81

Cell separation in a microfluidic channel using magnetic microspheres  

Microsoft Academic Search

Magnetophoretic isolation of biological cells in a microfluidic environment has strong relevance in biomedicine and biotechnology.\\u000a A numerical analysis of magnetophoretic cell separation using magnetic microspheres in a straight and a T-shaped microfluidic\\u000a channel under the influence of a line dipole is presented. The effect of coupled particle–fluid interactions on the fluid\\u000a flow and particle trajectories are investigated under different

Nipu Modak; Amitava Datta; Ranjan Ganguly

2009-01-01

82

Magnetic Separation of Ferrite Sludge from a Wastewater Purification Process  

Microsoft Academic Search

The purification of wastewater containing dissolved metal ions by in situ precipitation gives rise to a sludge composed mainly of ferrites MeXFe3-xO4 (where Me represents the existing metal ions in the wastewater). Oxides, iron oxy-hydroxides and other impurities are also present in the sludge in smaller proportion. The present investigation proposes magnetic separation of the sludge to recover the ferrites

E. Barrado; F. Prieto; J. Ribas; F. A. López

1999-01-01

83

Are There Separate Neural Systems for Spelling? New Insights into the Role of Rules and Memory in Spelling from Functional Magnetic Resonance Imaging.  

PubMed

How do people spell the thousands of words at the tips of their tongues? Are words with regular sound-to-letter correspondences (e.g., "blink") spelled using the same neural systems as those with irregular correspondences (e.g., "yacht")? By offering novel neuroimaging evidence, we aim to advance contemporary debate about whether people use a single lexical memory process or whether dual mechanisms of lexical memory and sublexical phonological rules work in concert. We further aim to advance understanding of how people read by taking a fresh look at the related yet distinct capacity to spell. During functional magnetic resonance imaging scanning, 12 participants heard low-frequency regular words, irregular words, and nonwords (e.g., "shelm") and responded whether a visual presentation of the word was spelled correctly or incorrectly. While behavioral measures suggested some differences in accuracy and reaction time for the different word types, the neuroimaging results alone demonstrated robust differential processing and support a dual-route model of spelling, with implications for how spelling is taught and remediated in clinical and educational contexts. PMID:20011680

Norton, Elizabeth S; Kovelman, Ioulia; Petitto, Laura-Ann

2007-03-01

84

Charge separation in a magnetized plasma-sheath-lens  

NASA Astrophysics Data System (ADS)

Most of plasma processing technologies are based on radical-assisted ion-induced surface-modification where ions accumulate energy in the sheath, and then strike the surface modifying its properties in a desirable way. Plasma-sheath-lens is a three-dimensional potential distribution of customized shape, formed by the space charge surrounding a biased electrode-insulator interface. The discrete and modal focusing effects have been reveled for this type of electrostatic structures formed in plasma [1] and several applications including sheath thickness evaluation, negative ion detection and extraction of positive or negative ion beams have been developed. A non-magnetized plasma-sheath-lens act as a kinetic energy separator, but it is not mass sensitive. However, a magnetized plasma-sheath-lens exhibits mass separation, so that ions of different mass will impact the electrode at different locations on the biased electrode surface. The mass spectrum can be measured as the radial distribution of the ion current density over the plasma-sheath-lens's electrode. Relevant fluid and particles simulations of the magnetized plasma-sheath-lens structures and ion trajectories within them are presented for different plasma parameters and magnetic filed configurations. Practical aspects linked to the development of a new type of mass spectrometers are also investigated.[0pt] [1] E. Stamate and H. Sugai, Phys. Rev. Lett. (2005) 94, 125004

Stamate, Eugen

2009-10-01

85

Radiolysis and hydrolysis of magnetically assisted chemical separation particles  

SciTech Connect

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 {mu}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 {sup 60}Co {gamma}-ray source, and evaluated for effectiveness in removing TRU elements from 2m HNO{sub 3} 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.

Buchholz, B.A.; Nunez, L.; Vandegrift, G.F.

1995-05-01

86

Separating key management from file system security  

Microsoft Academic Search

No secure network file system has ever grown to span the Internet. Existing systems all lack adequate key management for security at a global scale. Given the diversity of the Internet, any particular mechanism a file system employs to manage keys will fail to support many types of use.We propose separating key management from file system security, letting the world

David Mazières; Michael Kaminsky; M. Frans Kaashoek; Emmett Witchel

1999-01-01

87

Separating key management from file system security  

Microsoft Academic Search

Abstract No secure network file system has ever grown to span the Internet. Existing systems all lack adequate key management for security at a global scale. Given the diversity of the Internet, any particular mechanism a file system employs to manage,keys will fail to support many types of use. We propose separating key management,from file system security, letting the world

David Mazières; Michael Kaminsky; M. Frans Kaashoek; Emmett Witchel

2000-01-01

88

A NOVEL CO2 SEPARATION SYSTEM  

SciTech Connect

Because of concern over global climate change, new systems are needed that produce electricity from fossil fuels and emit less CO{sub 2}. The fundamental problem with current CO{sub 2} separation systems is the need to separate dilute CO{sub 2} and pressurize it for storage or sequestration. This is an energy intensive process that can reduce plant efficiency by 9-37% and double the cost of electricity.

Robert J. Copeland; Gokhan Alptekin; Mike Cesario; Steven Gebhard; Yevgenia Gershanovich

1999-01-01

89

Kinetic approach for the purification of nucleotides with magnetic separation.  

PubMed

The isolation of ?-nicotinamide adenine dinucleotide is of great importance since it is widely used in different scientific and technologic fields such as biofuel cells, sensor technology, and hydrogen production. In order to isolate ?-nicotinamide adenine dinucleotide, first 3-aminophenyboronic acid functionalized magnetic nanoparticles were prepared to serve as a magnetic solid support and subsequently they were used for reversible adsorption/desorption of ?-nicotinamide adenine dinucleotide in a batch fashion. The loading capacity of the 3-aminophenyboronic acid functionalized nanoparticles for ?-nicotinamide adenine dinucleotide adsorption was 13.0 ?mol/g. Adsorption kinetic and isotherm studies showed that the adsorption process followed a pseudo-second-order kinetic model and the experimental data can be represented using Langmuir isotherm model. The 3-aminophenyboronic acid functionalized magnetic nanoparticles were proposed as an alternative support for the ?-nicotinamide adenine dinucleotide purification. The results elucidated the significance of magnetic separation as a fast, relatively simple, and low-cost technique. Furthermore, the magnetic supports can be reused at least five times for purification processes. PMID:25199632

Tural, Servet; Tural, Bilsen; Ece, Mehmet ?akir; Yetkin, Evren; Ozkan, Necati

2014-11-01

90

Vision based magnetic levitation system  

Microsoft Academic Search

In this study, control of a vision based magnetic levitation system was explored. The system which is known as magnetic levitation or magnetic suspension constitutes the fundamental of the high speed maglev trains. The system levitates a ferro-magnetic object in the space using electromagnetic force against to gravity. The system consists of a coil, a controller, a position sensor, a

Selcuk Kizir; Gurkan Kucukyildiz; Hasan Ocak; Zafer Bingul

2012-01-01

91

Apparatus for magnetic separation of paramagnetic and diamagnetic material  

DOEpatents

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.

Doctor, Richard D. (Glen Ellyn, IL)

1988-01-01

92

Apparatus for magnetic separation of paramagnetic and diamagnetic material  

DOEpatents

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 quadrupole 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. 5 figs.

Doctor, R.D.

1986-07-24

93

Apparatus for magnetic separation of paramagnetic and diamagnetic material  

DOEpatents

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 quadrupole 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. 5 figs.

Doctor, R.D.

1988-10-18

94

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

NASA Astrophysics Data System (ADS)

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 ?-Fe 2O 3 (hematite) and ?-Fe 2O 3 (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.

Ha, D. W.; Kwon, J. M.; Baik, S. K.; Lee, Y. J.; Han, K. S.; Ko, R. K.; Sohn, M. H.; Seong, K. C.

2011-11-01

95

Design consideration for magnetically suspended flywheel systems  

NASA Technical Reports Server (NTRS)

Consideration is given to the design, fabrication, and testing of a magnetically suspended flywheel system for energy storage applications in space. The device is the prototype of a system combining passive suspension of the flywheel plate by samarium cobalt magnets and active control in the radial direction using eight separate magnetic coils. The bearing assembly was machined from a nickel-iron alloy, and the machine parts are all hydrogen annealed. Slots in the magnetic plate allow four independent quadrants for control. The motor/generator component of the system is a brushless dc-permanent magnetic/ironless engine using electronic communication. The system has been tested at over 2500 rpm with satisfactory results. The system characteristics of the flywheel for application in low earth orbit (LEO) are given in a table.

Anand, D.; Kirk, J. A.; Frommer, D. A.

1985-01-01

96

Magnetic materials as sorbents for metal/metalloid preconcentration and/or separation. A review.  

PubMed

The use of magnetic materials in solid phase extraction has received considerable attention in recent years taking into account many advantages arising from the inherent characteristics of magnetic particles. Magnetic solid phase extraction (MSPE) methodology overcomes problems such as column packing and phase separation, which can be easily performed by applying an external magnetic field. The use of magnetic particles in automatic systems is growing over the last few years making the on-line operation of MSPE a promising technique in the frame of green chemistry. This article aims to provide all recent progress in the research of novel magnetic materials as sorbents for metal preconcentration and determination coupled with different detection systems as well as their implementation in sequential injection and microfluidic systems. In addition, a description of preparation, characterization as well as applications of various types of magnetic materials, either with organic or inorganic coating of the magnetic core, is presented. Concluding remarks and future trends are also commented. PMID:23856225

Giakisikli, Georgia; Anthemidis, Aristidis N

2013-07-30

97

On-chip Magnetic Separation and Cell Encapsulation in Droplets†  

PubMed Central

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 would prevent cross-contamination, provide high recovery yield, and enable study of biological traits at a single cell level. These advantages of on-chip biological experiments is a significant improvement for myriad of cell analyses over conventional methods, which require bulk samples providing only averaged information on cell metabolism. We report on a device that integrates mobile magnetic trap array with microfluidic technology to provide, combined functionality of separation of immunomagnetically labeled cells or magnetic beads and their encapsulation with reagents into pico-liter droplets. This scheme of simultaneous reagent delivery and compartmentalization of the cells immediately after sorting, all performed seamlessly within the same chip, offers unique advantages such as the ability to capture cell traits as originated from its native environment, reduced chance of contamination, minimal use and freshness of the reagent solution that reacts only with separated objects, and tunable encapsulation characteristics independent of the input flow. In addition to the demonstrated preliminary cell viability assay, the device can potentially be integrated with other up- or downstream on-chip modules to become a powerful single-cell analysis tool. PMID:23370785

Chen, Aaron; Byvank, Tom; Chang, Woo-Jin; Bharde, Atul; Vieira, Greg; Miller, Brandon; Chalmers, Jeffrey J.; Bashir, Rashid; Sooryakumar, Ratnasingham

2014-01-01

98

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

NASA Astrophysics Data System (ADS)

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.

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

2014-09-01

99

Separable solutions for directly interacting particle systems  

Microsoft Academic Search

The problem of constructing a representation of the Poincaré group corresponding to a directly interacting system of a finite number of particles and satisfying the condition that the interaction be separable is considered by expansion of the group generators in powers of 1c2. It is established that the problem has a solution to order 1c2, but, except in special cases,

L. L. Foldy; R. A. Krajcik

1975-01-01

100

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

EPA Science Inventory

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...

101

Development of a high gradient magnetic separator using high temperature superconductors  

SciTech Connect

This is the final report of a one-year, Laboratory-Directed Research and Development (LDRD) project at the Los Alamos National Laboratory (LANL). High-gradient magnetic separation (HGMS) is an application of superconducting magnet technology to the process of magnetic separation of solids from other solids, liquids, or gases. The production of both high magnetic fields and large field gradients using superconducting magnet technology has made it possible to separate a previously unreachable but large family of paramagnetic materials. It is possible to separate more than half of the elements in the periodic table using this method. Because HGMS is a physical separation process, no additional or mixed waste is generated. This project sought to develop a high-gradient magnetic separator using a high-temperature superconducting magnet.

Prenger, F.C.; Daney, D.; Daugherty, M.; Hill, D.

1996-09-01

102

The Development of the Separation Apparatus of Phosphor by Controlling the Magnetic Force  

NASA Astrophysics Data System (ADS)

The phosphor wastes contain the multiple kinds of rare-earth phosphors with high market value. Because of increasing demand for rare-earth, the technique to recover and reuse the rare-earth in the phosphor wastes is required. In this study, we focused on the difference of physical property such as magnetic susceptibility and density for each type of phosphor and tried to separate and recover the phosphors by using the magnetic separation technique utilizing the difference of the traction force to the magnet acting on the particles. Magneto-Archimedes method is method separation technique utilizi g the difference of magnetic susceptibility and density. We developed the magnetic separation apparatus by applying this technique. To develop the practical separation apparatus, the continuous process is required. Hence the fundamental experiment utilizing High Temperature Superconducting (HTS) Bulk Magnet which can generate the strong magnetic force was conducted. As a result, we succeeded the continuous separation of the phosphor wastes.

Wada, K.; Mishima, F.; Akiyama, Y.; Nishijima, S.

103

Are There Separate Neural Systems for Spelling? New Insights into the Role of Rules and Memory in Spelling from Functional Magnetic Resonance Imaging  

ERIC Educational Resources Information Center

How do people spell the thousands of words at the tips of their tongues? Are words with "regular" sound-to-letter correspondences (e.g., "blink") spelled using the same neural systems as those with "irregular" correspondences (e.g., "yacht")? By offering novel neuroimaging evidence, we aim to advance contemporary debate about whether people use a…

Norton, Elizabeth S.; Kovelman, Ioulia; Petitto, Laura-Ann

2007-01-01

104

A novel bubbling-assisted exfoliating method preparation of magnetically separable ?-Fe2O3/graphene recyclable photocatalysts  

NASA Astrophysics Data System (ADS)

A facile and novel bubbling-assisted exfoliating method was developed for the preparation of ?-Fe2O3/graphene composite, which showed desirable photocatalytic activity toward methyl orange with excellent cycling abilities and the possible growth mechanism was discussed. Photocatalytic and magnetic properties measurements show that the composite has excellent recyclable degradation efficiency and soft magnetic parameters, which makes the composite magnetically separable in a suspension system and can be recycled without significant loss of catalytic activity.

Zhang, Lili; Hu, Hongrui; Wu, Mingzai; Yu, Xinxin; Sun, Zhaoqi; Li, Guang; Liu, Xiansong; Zheng, Xiuwen

2014-06-01

105

System Synchronizes Recordings from Separated Video Cameras  

NASA Technical Reports Server (NTRS)

A system of electronic hardware and software for synchronizing recordings from multiple, physically separated video cameras is being developed, primarily for use in multiple-look-angle video production. The system, the time code used in the system, and the underlying method of synchronization upon which the design of the system is based are denoted generally by the term "Geo-TimeCode(TradeMark)." The system is embodied mostly in compact, lightweight, portable units (see figure) denoted video time-code units (VTUs) - one VTU for each video camera. The system is scalable in that any number of camera recordings can be synchronized. The estimated retail price per unit would be about $350 (in 2006 dollars). The need for this or another synchronization system external to video cameras arises because most video cameras do not include internal means for maintaining synchronization with other video cameras. Unlike prior video-camera-synchronization systems, this system does not depend on continuous cable or radio links between cameras (however, it does depend on occasional cable links lasting a few seconds). Also, whereas the time codes used in prior video-camera-synchronization systems typically repeat after 24 hours, the time code used in this system does not repeat for slightly more than 136 years; hence, this system is much better suited for long-term deployment of multiple cameras.

Nail, William; Nail, William L.; Nail, Jasper M.; Le, Doung T.

2009-01-01

106

Method and apparatus for separating materials magnetically. [Patent application; iron pyrite from coal  

DOEpatents

Magnetic and nonmagnetic materials are separated by passing stream thereof past coaxial current-carrying coils which produce a magnetic field wherein intensity varies sharply with distance radially of the axis of the coils.

Hise, E.C. Jr.; Holman, A.S.; Friedlaender, F.J.

1980-11-06

107

The principles and operation of a very high intensity magnetic mineral separator  

Microsoft Academic Search

A magnetic separator is described which employs a superconducting quadrupole magnet. The magnet is installed in a vertical cylindrical cryostat with hollow central portion. The magnetic forces are substantially in the radial direction. The results of trial experiments are described with various configurations of mineral slurries and wash water streams. In the preferred configuration, mineral slurry travels around the outer

HENRY COHEN; JEREMY A. GOOD

1976-01-01

108

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

EPA Science Inventory

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...

109

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

PubMed

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 (88)Sr(+) 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. PMID:24943952

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

2014-06-19

110

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

NASA Astrophysics Data System (ADS)

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.

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

2014-06-01

111

46 CFR 153.292 - Separation of piping systems.  

Code of Federal Regulations, 2010 CFR

...2010-10-01 2010-10-01 false Separation of piping systems. 153.292 Section 153...Design and Equipment Piping Systems and Cargo Handling Equipment § 153.292 Separation of piping systems. Cargo piping systems...

2010-10-01

112

46 CFR 153.292 - Separation of piping systems.  

Code of Federal Regulations, 2011 CFR

...2011-10-01 2011-10-01 false Separation of piping systems. 153.292 Section 153...Design and Equipment Piping Systems and Cargo Handling Equipment § 153.292 Separation of piping systems. Cargo piping systems...

2011-10-01

113

Superconducting bulk magnets for magnetic levitation systems  

NASA Astrophysics Data System (ADS)

The major applications of high-temperature superconductors have mostly been confined to products in the form of wires and thin films. However, recent developments show that rare-earth REBa 2Cu 3O 7- x and light rare-earth LREBa 2Cu 3O 7- x superconductors prepared by melt processes have a high critical-current density at 77 K and high magnetic fields. These superconductors will promote the application of bulk high-temperature superconductors in high magnetic fields; the superconducting bulk magnet for the Maglev train is one possible application. We investigated the possibility of using bulk magnets in the Maglev system, and examined flux-trapping characteristics of multi-superconducting bulks arranged in array.

Fujimoto, H.; Kamijo, H.

2000-06-01

114

Application of high temperature superconductors to high-gradient magnetic separation  

SciTech Connect

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 we 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.

Daugherty, M.A.; Prenger, F.C.; Hill, D.D.; Daney, D.E.; Worl, L.W.; Schake, A.R.; Padilla, D.D.

1994-06-01

115

Cesium separation from contaminated milk using magnetic particles containing crystalline silicotitantes.  

SciTech Connect

The Chernobyl nuclear reactor disaster in 1986 contaminated vast regions of prime grazing land. Subsequently, milk produced in the region has been contaminated with small amounts of the long-lived fission product cesium-137, and the Ukraine is seeking to deploy a simple separation process that will remove the Cs and preserve the nutritional value of the milk. Tiny magnetic particles containing crystalline silicotitanates (CST) have been manufactured and tested to this end. The results show that partitioning efficiency is optimized with low ratios of particle mass to volume. To achieve 90% Cs decontamination in a single-stage process, <3 g of magnetic CST per l milk is sufficient with a 30-min mixing time. A two-stage process would utilize <0.4 g/l per stage. The modeling of the magnetic CST system described herein can be achieved rather simply which is important for deployment in the affected Ukraine region.

Nunez, L.; Kaminski, M.; Chemical Engineering

2000-11-01

116

An integrated microfluidic platform for magnetic microbeads separation and confinement  

Microsoft Academic Search

An innovative microfluidic platform for magnetic beads manipulation is introduced, consisting of novel microfabricated 3D magnetic devices positioned in a microfluidic chamber. Each magnetic device comprises of an embedded actuation micro-coil in various design versions, a ferromagnetic pillar, a magnetic backside plate and a sensing micro-coil. The various designs of the micro-coils enable efficient magnetic beads trapping and concentration in

Qasem Ramadan; Victor Samper; Daniel P. Poenar; Chen Yu

2006-01-01

117

[Actual modalities of separation by magnetic methods of active biological compounds, cells and pathogenic agents].  

PubMed

The paper presents an overview on magnetic techniques of bio-processing and some of their possible applications. These techniques are in fact direct, or more frequently, indirect magnetic means for separation of particulate substances. A brief presentation of direct and of the most important indirect methods (magnetic carrier and magnetic fluids technologies) is made. There are shown some of the possible applications of magnetic bio-processing in bio-technology and medicine: active biological compounds fixation, isolation and modification, cells and cells organelles separation, removal of xenobiotics, immuno-magnetic testing, pathogen microbes identification. PMID:12092161

Iacob, G; Brede?ean, O; Ciochin?, A D

2001-01-01

118

Separability and ground state factorization in quantum spin systems  

E-print Network

We investigate the existence and the properties of fully separable (fully factorized) ground states in quantum spin systems. Exploiting techniques of quantum information and entanglement theory we extend a recently introduced method and construct a general, self-contained theory of ground state factorization in frustration-free quantum spin models defined on lattices in any spatial dimension and for interactions of arbitrary range. We show that, quite generally, non exactly solvable models in external field admit exact, fully factorized ground state solutions. Unentangled ground states occur at finite values of the Hamiltonian parameters satisfying well defined balancing conditions between external fields and interaction strengths. These conditions are analytically determined together with the type of magnetic orderings compatible with factorization and the corresponding values of the fundamental observables such as energy and magnetization. The method is applied to a series of examples of increasing complexi...

Giampaolo, S M; Illuminati, F

2009-01-01

119

Surface molecular imprinting onto fluorescein-coated magnetic nanoparticles via reversible addition fragmentation chain transfer polymerization: A facile three-in-one system for recognition and separation of endocrine disrupting chemicals  

NASA Astrophysics Data System (ADS)

In this study, we present a general protocol for the making of surface-imprinted magnetic fluorescence beads via reversible addition-fragmentation chain transfer polymerization. The resulting composites were characterized by X-ray diffraction analysis, transmission electron microscopy, scanning electron microscopy, fluorescence spectroscopy, Fourier transform infrared spectroscopy, and energy dispersive spectroscopy. The as-synthesized beads exhibited homogeneous polymer films (thickness of about 5.7 nm), spherical shape, high fluorescence intensity and magnetic property (Magnetization (Ms) = 3.67 emu g-1). The hybrids bind the original template 17?-estradiol with an appreciable selectivity over structurally related compounds. In addition, the resulting hybrids performed without obvious deterioration after five repeated cycles. This study therefore demonstrates the potential of molecularly imprinted polymers for the recognition and separation of endocrine disrupting chemicals.In this study, we present a general protocol for the making of surface-imprinted magnetic fluorescence beads via reversible addition-fragmentation chain transfer polymerization. The resulting composites were characterized by X-ray diffraction analysis, transmission electron microscopy, scanning electron microscopy, fluorescence spectroscopy, Fourier transform infrared spectroscopy, and energy dispersive spectroscopy. The as-synthesized beads exhibited homogeneous polymer films (thickness of about 5.7 nm), spherical shape, high fluorescence intensity and magnetic property (Magnetization (Ms) = 3.67 emu g-1). The hybrids bind the original template 17?-estradiol with an appreciable selectivity over structurally related compounds. In addition, the resulting hybrids performed without obvious deterioration after five repeated cycles. This study therefore demonstrates the potential of molecularly imprinted polymers for the recognition and separation of endocrine disrupting chemicals. Electronic supplementary information (ESI) available: Supplementary figure S1. The hysteresis loop of Fe3O4 (a), Fe3O4@SiO2 (b), and Fe3O4@SiO2-Dye-SiO2 (c). See DOI: 10.1039/c0nr00614a

Li, Ying; Dong, Cunku; Chu, Jia; Qi, Jingyao; Li, Xin

2011-01-01

120

Nanomagnetism of Core-Shell Magnetic Nanoparticles and Application in Spent Nuclear Fuel Separation  

NASA Astrophysics Data System (ADS)

This dissertation presents the study on novel core-shell magnetic nanoparticles (NPs) with unique magnetic properties. Understanding the fundamental physics of antiferromagnetic - ferromagnetic interactions is essential to apply in different applications. Chromium (Cr) doped and undoped core-shell iron/iron-oxide NPs have been synthesized using cluster deposition system and studied with respect to their nanostructures, morphologies, sizes, chemical composition and magnetic properties. The room-temperature magnetic properties of Fe based NPs shows the strong dependence of intra/inter-particle interaction on NP size. The Cr-doped Fe NP shows the origin of sigma-FeCr phase at very low Cr concentration (2 at.%) unlike others reported at high Cr content and interaction reversal from dipolar to exchange interaction. A theoretical model of watermelon is constructed based on the experimental results and core-shell NP system in order to explain the physics of exchange interaction in Cr-doped Fe particles. The magnetic nanoparticle---chelator separation nanotechnology is investigated for spent nuclear fuel recycling and is reported 97% and 80% of extraction for Am(III) and Pu(IV) actinides respectively. If the long-term heat generating actinides such as Am(III) 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. As it is a simple, versatile, compact, and cost efficient process that minimizes secondary waste and improves storage performance.

Tarsem Singh, Maninder Kaur

121

Solar System Magnetism  

NSDL National Science Digital Library

This is an activity about magnetism. In this activity, polystyrene spheres and several strong neodymium magnets are used to represent the Sun and Earth and their distinct magnetic fields. Participants construct and use a field detector to predict where the magnetic fields are on the Sun and Earth, and use field bits, which is the term used in the lesson plan, made from the closed staples to form loops and trace the invisible magnetic fields of the Sun and Earth. The activity is designed to be used in an informal public outreach setting, for example as a stand-alone station in a family science day event. It can also be modified for use as a simple classroom demonstration. There are background information sheets provided that can be printed to go along with the activity station. This activity requires two polystyrene spheres, 8 neodymium magnets, epoxy adhesive, wire clippers, needle nose pliers, and acrylic paints, along with other easily obtained materials.

122

Application concepts of small regenerative cryocoolers in superconducting magnet systems  

NASA Astrophysics Data System (ADS)

Superconducting magnets are in growing use outside laboratories for example MRI scanners in hospitals. Other applications under development are magnet systems for separation, levitated trains and ship propulsion. The application of cryocoolers can make these systems more practical. Interfacing these cryocoolers to the magnets can be designed in several different ways. The four basic methods will be dealt with. Test results of a realized GM cryocooler-SC magnet system will be shown. It handles about a 1:3 scale MRI magnet of which one of the six coils has been successfully tested at temperatures between 10 and 14 K.

van der Laan, M. T. G.; Tax, R. B.; ten Kate, H. H. J.

123

HIGH-GRADIENT MAGNETIC SEPARATION FOR REMOVAL OF SULFUR FROM COAL  

EPA Science Inventory

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 ...

124

High Temperature Superconducting Reciprocating Magnetic Separator; Final Report  

Microsoft Academic Search

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

James F. Maguire

2008-01-01

125

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

PubMed Central

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

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

126

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

SciTech Connect

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 (0.0078

Wu, Shen; Sun, Aizhi; Xu, Wenhuan; Zou, Chao; Yang, Jun; Dong, Juan [School of Materials Science and Engineering, University of Science and Technology Beijing, Beijing (China)

2013-12-16

127

High magnetic field far-infrared spectroscopy of spatially separated electron-hole layers  

NASA Astrophysics Data System (ADS)

Cyclotron resonance (CR) experiments have been performed on InAs/GaSb structures, in which InAs (electron) and GaSb (hole) layers are separated by AlSb barriers. Our data reveal that properties of InAs/GaSb systems with AlSb barriers thinner than 1.5 nm are entirely determined by interlayer tunneling and the CR features in such samples can be explained by hybridization between states in the InAs conduction band and in the GaSb valence band. The hybridization gap has been estimated from CR spectra for two samples with different degrees of electron-hole coupling. The CR spectra of widely separated electron-hole layers (with barriers thicker than 2 nm) are characterized by pronounced spin splitting. In addition to multiple spin-split CR lines new lines have been observed at high magnetic fields (11-13 T).

Vasilyev, Yu. B.; Suchalkin, S. D.; Klitzing, K. v.; Meltser, B. Ya.; Ivanov, S. V.; Kop'ev, P. S.

1998-12-01

128

Tribology of magnetic storage systems  

NASA Technical Reports Server (NTRS)

The construction and the materials used in different magnetic storage devices are defined. The theories of friction and adhesion, interface temperatures, wear, and solid-liquid lubrication relevant to magnetic storage systems are presented. Experimental data are presented wherever possible to support the relevant theories advanced.

Bhushan, Bharat

1992-01-01

129

Compact magnetic levitation transportation system  

SciTech Connect

This patent describes a magnetic levitation transportation system, it comprises: vehicle loading and unloading stations, at least one primary pair of laterally spaced rails comprises of magnetically interactive material extending between the vehicle loading and unloading stations, a vehicle of a size, a magnetic levitation means, energy conversion means for energizing the magnetic levitation means on the vehicle and for maintaining the speed and acceleration of the vehicle during travel, braking control means for creating a net braking force on the vehicle in a braking condition, and speed control means on the vehicle for accelerating and decelerating the vehicle.

Suppes, G.J.

1992-09-15

130

Enhanced separation of magnetic and diamagnetic particles in a dilute Litao Liang, Cheng Zhang, and Xiangchun Xuan  

E-print Network

Enhanced separation of magnetic and diamagnetic particles in a dilute ferrofluid Litao Liang, Cheng://apl.aip.org/authors #12;Enhanced separation of magnetic and diamagnetic particles in a dilute ferrofluid Litao Liang,1) Traditional magnetic field-induced particle separations take place in water-based diamagnetic solutions, where

Xuan, Xiangchun "Schwann"

131

Removal of algal blooms from freshwater by the coagulation-magnetic separation method.  

PubMed

This research investigated the feasibility of changing waste into useful materials for water treatment and proposed a coagulation-magnetic separation technique. This technique was rapid and highly effective for clearing up harmful algal blooms in freshwater and mitigating lake eutrophication. A magnetic coagulant was synthesized by compounding acid-modified fly ash with magnetite (Fe(3)O(4)). Its removal effects on algal cells and dissolved organics in water were studied. After mixing, coagulation, and magnetic separation, the flocs obtained from the magnet surface were examined by SEM. Treated samples were withdrawn for the content determination of chlorophyll-a, turbidity, chemical oxygen demand (COD), total nitrogen, and total phosphorus. More than 99 % of algal cells were removed within 5 min after the addition of magnetic coagulant at optimal loadings (200 mg L(-1)). The removal efficiencies of COD, total nitrogen, and phosphorus were 93, 91, and 94 %, respectively. The mechanism of algal removal explored preliminarily showed that the magnetic coagulant played multiple roles in mesoporous adsorption, netting and bridging, as well as high magnetic responsiveness to a magnetic field. The magnetic-coagulation separation method can rapidly and effectively remove algae from water bodies and greatly mitigate eutrophication of freshwater using a new magnetic coagulant. The method has good performance, is low cost, can turn waste into something valuable, and provides reference and directions for future pilot and production scale-ups. PMID:22767355

Liu, Dan; Wang, Peng; Wei, Guanran; Dong, Wenbo; Hui, Franck

2013-01-01

132

The ESRF Miniature Pulsed Magnetic Field System  

NASA Astrophysics Data System (ADS)

We have developed a portable system to provide pulsed magnetic fields on the ESRF X-ray beamlines. The complete system consists of a power supply, liquid Helium and liquid Nitrogen dewars with a siphon each, control electronics and a double cryostat for separate coil and sample cooling. The liquid nitrogen cooled solenoids reach a maximum field of 30 Tesla for a total pulse duration of one milisecond. They are constructed for optimised cooling rate after the pulse to obtain a high duty cycle, the repetition rate is five pulses per minute at maximum field. The sample is cooled in an independent Helium flow cryostat which is inserted into the bore of the magnet. The flow cryostat has a temperature range from 5 to 250 Kelvin with a direct contact between the sample and Helium flow. This overview gives a general presentation of the system and we will show recent results.

van der Linden, Peter J. E. M.; Strohm, Cornelius; Roth, Thomas; Detlefs, Carsten; Mathon, Olivier

2010-06-01

133

The ESRF Miniature Pulsed Magnetic Field System  

SciTech Connect

We have developed a portable system to provide pulsed magnetic fields on the ESRF X-ray beamlines. The complete system consists of a power supply, liquid Helium and liquid Nitrogen dewars with a siphon each, control electronics and a double cryostat for separate coil and sample cooling. The liquid nitrogen cooled solenoids reach a maximum field of 30 Tesla for a total pulse duration of one milisecond. They are constructed for optimised cooling rate after the pulse to obtain a high duty cycle, the repetition rate is five pulses per minute at maximum field. The sample is cooled in an independent Helium flow cryostat which is inserted into the bore of the magnet. The flow cryostat has a temperature range from 5 to 250 Kelvin with a direct contact between the sample and Helium flow. This overview gives a general presentation of the system and we will show recent results.

Linden, Peter J. E. M. van der; Strohm, Cornelius; Roth, Thomas; Detlefs, Carsten; Mathon, Olivier [ESRF, 6 rue Jules Horowitz, F-38043 Grenoble (France)

2010-06-23

134

Transcranial Magnetic Stimulation in a Finger-tapping Task Separates Motor from Timing  

E-print Network

Transcranial Magnetic Stimulation in a Finger- tapping Task Separates Motor from Timing Mechanisms and of return to stability using error correction. The advent of transcranial magnetic stimulation (TMS) has by using precise pulses of transcranial mag- netic stimulation (TMS) applied to the primary motor cortex

Moses, Elisha

135

Superconducting open-gradient magnetic separation for the pretreatment of radioactive or mixed waste vitrification feeds. 1997 annual progress report  

SciTech Connect

'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 Fe{sub 3}O{sub 4} and FeCrO{sub 4}, 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.'

Doctor, R.; Nunez, L. [Argonne National Lab., IL (US); Cicero-Herman, C.A. [Westinghouse Savannah River Co., Aiken, SC (US). Savannah River Technology Center; Ritter, J.A. [Univ. of South Carolina, Columbia, SC (US). Chemical Engineering Dept.; Landsberger, S. [Univ. of Texas, Austin, TX (US). Nuclear Engineering Dept.

1997-01-01

136

A method for perfonning magnetic mineral separations in a liquid 6s{inm  

Microsoft Academic Search

A method for performing magnetic separations of minerals in a liquid medium with the Franz separator is described. The method is successful for applications where only small sample weights (<200 mg) are available and the sieve size of the particles is small (<53p).

Gnecony R. LuuprtN

137

Magnetic Launch Assist System Demonstration  

NASA Technical Reports Server (NTRS)

This Quick Time movie demonstrates the Magnetic Launch Assist system, previously referred to as the Magnetic Levitation (Maglev) system, for space launch using a 5 foot model of a reusable Bantam Class launch vehicle on a 50 foot track that provided 6-g acceleration and 6-g de-acceleration. Overcoming the grip of Earth's gravity is a supreme challenge for engineers who design rockets that leave the planet. Engineers at the Marshall Space Flight Center have developed and tested Magnetic Launch Assist technologies that could levitate and accelerate a launch vehicle along a track at high speeds before it leaves the ground. Using electricity and magnetic fields, a Magnetic Launch Assist system would drive a spacecraft along a horizontal track until it reaches desired speeds. A full-scale, operational track would be about 1.5-miles long and capable of accelerating a vehicle to 600 mph in 9.5 seconds. The major advantages of launch assist for NASA launch vehicles is that it reduces the weight of the takeoff, the landing gear, the wing size, and less propellant resulting in significant cost savings. The US Navy and the British MOD (Ministry of Defense) are planning to use magnetic launch assist for their next generation aircraft carriers as the aircraft launch system. The US Army is considering using this technology for launching target drones for anti-aircraft training.

1999-01-01

138

Separation of magnetically isolated TNF receptosomes from mitochondria.  

PubMed

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

Tchikov, Vladimir; Fritsch, Jürgen; Schütze, Stefan

2014-01-01

139

The 13th International Conference on Magnetically Levitated Systems and Linear Drives MAGLEV 1993  

NASA Astrophysics Data System (ADS)

This report contains short papers on research being conducted throughout the world on magnetically levitated systems, mainly consisting of trains, and magnetic linear drives. These papers have been index separately elsewhere on the data base.

140

13th International Conference on Magnetically Levitated Systems and Linear Drives  

SciTech Connect

This report contains short papers on research being conducted throughout the world on magnetically levitated systems, mainly consisting of trains, and magnetic linear drives. These papers have been index separately elsewhere on the data base.

Not Available

1993-09-01

141

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

PubMed Central

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 in the IC. After sedimentation, the magnetic beads that did not bind strongly to the functionalized surface of the IC through a specific biochemical complex were removed by a magnetic separation force generated by flowing current through another conductor placed laterally to the detection area. As the spherical bead pivoted on the surface of the chip, the lateral magnetic force was further amplified by mechanical leveraging, and 50 mA of current flowing through the separation conductor placed 18 ?m away from the bead resulted in 7.5 pN of tensile force on the biomolecular tether immobilizing the bead. This force proved high enough to break nonspecific interactions while leaving specific antibody-antigen bonds intact. A sandwich capture immunoassay on purified human immunoglobulin G showed strong correlation with a control enzyme linked immunosorbent assay and a detection limit of 10 ng?ml or 70 pM. The beads bound to the detection area after on-chip magnetic separation were detected optically. To implement a fully integrated molecular diagnostics platform, the on-chip magnetic separation functionality presented in this work can be readily combine with state-of-the art CMOS-based magnetic bead detection technology. PMID:20368988

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

2010-01-01

142

Separator-spacer for electrochemical systems  

DOEpatents

An electrochemical cell construction features a novel co-extruded plastic electrode in an interleaved construction with a novel integral separator-spacer. Also featured is a leak and impact resistant construction for preventing the spill of corrosive materials in the event of rupture.

Grimes, Patrick G. (Westfield, NJ); Einstein, Harry (Springfield, NJ); Newby, Kenneth R. (Berkeley Heights, NJ); Bellows, Richard J. (Westfield, NJ)

1983-08-02

143

Advanced separation processes for sustainable nuclear systems  

Microsoft Academic Search

In the frame of the French national waste management 1991 act, the CEA had launched research and development studies on the separation of the minor actinides - i.e. neptunium, americium and curium - from high active waste issuing from nuclear spent fuel reprocessing. In compliance with the 2006 deadline specified by this act, tests of the main processes developed were

P. Baron; M. Masson; C. Rostaing; B. Boullis

2007-01-01

144

Estimation of Separation Buffers for Wind-Prediction Error in an Airborne Separation Assistance System  

NASA Technical Reports Server (NTRS)

Wind prediction errors are known to affect the performance of automated air traffic management tools that rely on aircraft trajectory predictions. In particular, automated separation assurance tools, planned as part of the NextGen concept of operations, must be designed to account and compensate for the impact of wind prediction errors and other system uncertainties. In this paper we describe a high fidelity batch simulation study designed to estimate the separation distance required to compensate for the effects of wind-prediction errors throughout increasing traffic density on an airborne separation assistance system. These experimental runs are part of the Safety Performance of Airborne Separation experiment suite that examines the safety implications of prediction errors and system uncertainties on airborne separation assurance systems. In this experiment, wind-prediction errors were varied between zero and forty knots while traffic density was increased several times current traffic levels. In order to accurately measure the full unmitigated impact of wind-prediction errors, no uncertainty buffers were added to the separation minima. The goal of the study was to measure the impact of wind-prediction errors in order to estimate the additional separation buffers necessary to preserve separation and to provide a baseline for future analyses. Buffer estimations from this study will be used and verified in upcoming safety evaluation experiments under similar simulation conditions. Results suggest that the strategic airborne separation functions exercised in this experiment can sustain wind prediction errors up to 40kts at current day air traffic density with no additional separation distance buffer and at eight times the current day with no more than a 60% increase in separation distance buffer.

Consiglio, Maria C.; Hoadley, Sherwood T.; Allen, B. Danette

2009-01-01

145

Fluidized bed riser as a dry particle separation system  

SciTech Connect

An exploratory study was undertaken to demonstrate the potential for using a fluidized bed riser system for the dry separation of fine particles. The experimental system consisted of a constant-diameter riser, two different operational heights, optional internal rings and one specific test mixture. Good separation efficiencies were obtained with a modest mass flux through the system. Further research is required to optimize the separation process and bring the concept to commercial viability.

Johnson, E.K.; Regester, J.L.; Kang, B.S-J. [West Virginia University, Morgantown, WV (United States). Dept. of Aerospace & Mechanical Engineering

2005-08-01

146

Magnetic interaction in the metamaterial/magnet system  

NASA Astrophysics Data System (ADS)

The stability of the magnetic dipole and the metamaterial with negative permeability are investigated. Analytical expressions of the interaction force and stiffness of the magnetic line and metamaterial with negative permeability are derived. The repulsive force between the magnetic line and the metamaterial exceeds the value of the maximum force in the magnet-superconductor system.

K. Alqadi, M.; Y. Alzoubi, F.

2014-08-01

147

Fluidized bed riser as a dry particle separation system  

Microsoft Academic Search

An exploratory study was undertaken to demonstrate the potential for using a fluidized bed riser system for the dry separation of fine particles. The experimental system consisted of a constant-diameter riser, two different operational heights, optional internal rings and one specific test mixture. Good separation efficiencies were obtained with a modest mass flux through the system. Further research is required

E. K. Johnson; J. L. Regester; B. S. J. Kang

2005-01-01

148

Method for separating biological cells. [suspended in aqueous polymer systems  

NASA Technical Reports Server (NTRS)

A method for separating biological cells by suspending a mixed cell population in a two-phase polymer system is described. The polymer system consists of droplet phases with different surface potentials for which the cell populations exhibit different affinities. The system is subjected to an electrostatic field of sufficient intensity to cause migration of the droplets with an attendant separation of cells.

Brooks, D. E. (inventor)

1980-01-01

149

High Temperature Superconducting Reciprocating Magnetic Separator Final Report  

SciTech Connect

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.

James F. Maguire

2008-06-05

150

Removal of freshwater microalgae by a magnetic separation method  

NASA Astrophysics Data System (ADS)

Some species of microalgae, with high growth rate and high lipid content, appear to be attractive alternatives as a feedstock for biodiesel production. The high-energy input for harvesting biomass and removing the water from the algae makes current commercial microalgal biodiesel production cost expensive. The major techniques currently employed in microalgae harvesting and recovery include centrifugation, coagulation-flocculation, bio-flocculation, filtration and screening, gravity sedimentation, and flotation. The purpose of this study was to investigate the harvesting of microalgae cells by coagulation using magnetic activated carbon, magnetite (FeO4) nanoparticles, and common chemical coagulants. Scenedesmus rubescens was selected and cultivated in 10 L flasks under continuous artificial light. Samples were taken at different operation intervals. Jar tests were conducted to investigate the effect of adsorption of microalgae on the magnetic material. The removal efficiency of microalgae was affected by the coagulants dose, stirring time and speed, and the initial microalgae concentration. The recovery of microalgae was greater in cultures with high initial microalgae concentration compared to cultures with low microalgae concentrations.

Vergini, Sofia S.; Aravantinou, Andriana F.; Manariotis, Ioannis D.

2013-04-01

151

Metalizing reduction and magnetic separation of vanadium titano-magnetite based on hot briquetting  

NASA Astrophysics Data System (ADS)

To achieve high efficiency utilization of Panzhihua vanadium titano-magnetite, a new process of metalizing reduction and magnetic separation based on hot briquetting is proposed, and factors that affect the cold strength of the hot-briquetting products and the efficiency of reduction and magnetic separation are successively investigated through laboratory experiments. The relevant mechanisms are elucidated on the basis of microstructural observations. Experimental results show that the optimal process parameters for hot briquetting include a hot briquetting temperature of 475°C, a carbon ratio of 1.2, ore and coal particle sizes of less than 74 ?m. Additionally, with respect to metalizing reduction and magnetic separation, the rational parameters include a magnetic field intensity of 50 mT, a reduction temperature of 1350°C, a reduction time of 60 min, and a carbon ratio of 1.2. Under these above conditions, the crushing strength of the hot-briquetting agglomerates is 1480 N, and the recovery ratios of iron, vanadium, and titanium are as high as 91.19%, 61.82%, and 85.31%, respectively. The new process of metalizing reduction and magnetic separation based on hot briquetting demonstrates the evident technological advantages of high efficiency separation of iron from other valuable elements in the vanadium titano-magnetite.

Chen, Shuang-yin; Chu, Man-sheng

2014-03-01

152

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

NASA Astrophysics Data System (ADS)

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.

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

2014-10-01

153

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

PubMed

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

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

2014-07-01

154

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

SciTech Connect

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.

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

155

Separating Data and Control Transfer in Distributed Operating Systems  

E-print Network

Separating Data and Control Transfer in Distributed Operating Systems Chandramohan A. Thekkath, October 1994. 1 #12;Separating Data and Control Transfer in Distributed Operating Systems Chandramohan A increased reliability, when compared to current LANs such as Ethernet. We believe that these new network

Thekkath, Chandramohan A.

156

Separation of Nanoparticles in Aqueous Multiphase Systems through Centrifugation  

E-print Network

of the particles (e.g., Au = 19.3 g/cm3 and media = 1.0-1.4 g/cm3 for aqueous solutions of sucrose). ViscositySeparation of Nanoparticles in Aqueous Multiphase Systems through Centrifugation Ozge Akbulut of aqueous multiphase systems (MuPSs) as media for rate-zonal centrifugation to separate nanoparticles

Liu, David R.

157

Magnetoresistive phenomena in nanoscale magnetic systems  

NASA Astrophysics Data System (ADS)

Nanomagnetic materials are playing an increasingly important role in modern technologies. A particular area of interest involves the interplay between magnetism and electric transport, i.e. magnetoresistive properties. Future generations of field sensors and memory elements will have to be on a length scale of a few nanometers or smaller. Magnetoresistive properties of such nanoscale objects exhibit novel features due to reduced dimensionality, complex surfaces and interfaces, and quantum effects. In this dissertation theoretical aspects of three such nanoscale magnetoresistive phenomena are discussed. Very narrow magnetic domain walls can strongly scatter electrons leading to an increased resistance. Specifically, this dissertation will cover the newly predicted effect of magnetic moment softening in magnetic nanocontacts or nanowires. Atomically thin domain walls in Ni exhibit a reduction, or softening, of the local magnetic moments due to the noncollinearity of the magnetization. This effect leads to a strong enhancement of the resistance of a domain wall. Magnetic tunnel junctions (MTJs) consist of two ferromagnetic electrodes separated by a thin layer of insulating material through which current can be carried by electron tunneling. The resistance of an MTJ depends on the relative orientation of the magnetization of the two ferromagnetic layers, an effect known as tunneling magnetoresistance (TMR). A first-principles analysis of CoFeB|MgO|CoFeB MTJs will be presented. Calculations reveal that it is energetically favorable for interstitial boron atoms to reside at the interface between the electrode and MgO tunneling barrier, which can be detrimental to the TMR effect. Anisotropic magnetoresistance (AMR) is the change in resistance of a ferromagnetic system as the orientation of the magnetization is altered. In this dissertation, the focus will be on AMR in the tunneling regime. Specifically we will present new theoretical results on tunneling AMR (TAMR) in two systems: (i) planar MTJs with CoFe electrodes and (ii) fully broken magnetic break junctions. In both cases electronic resonances in the electrodes lead to complex angular and bias dependence of the TAMR. The theoretical studies demonstrate the basic physical phenomenon behind recent experimental data.

Burton, John D.

158

Magnetically suspended flywheel system study  

SciTech Connect

A program to study the application of a graphite/epoxy, magnetically suspended, pierced disk flywheel for the combined function of spacecraft attitude control and energy storage (ACES) is described. Past achievements of the program include design and analysis computer codes for the flywheel rotor, a magnetically suspended flywheel model, and graphite/epoxy rotor rings that were successfully prestressed via interference assembly. All hardware successfully demonstrated operation of the necessary subsystems which form a complete ACES design. Areas of future work include additional rotor design research, system definition and control strategies, prototype development, and design/construction of a UM/GSFC spin test facility. The results of applying design and analysis computer codes to a magnetically suspended interference assembled rotor show specific energy densities of 42 Wh/lb (92.4 Wh/kg) are obtained for a 1.6 kWh system.

Kirk, J.A.; Anand, D.K.; Evans, H.E.; Rodriguez, G.E.

1984-11-01

159

Electric and Magnetic Manipulation of Biological Systems  

NASA Astrophysics Data System (ADS)

New types of biological cell manipulation systems, a micropost matrix, a microelectromagnet matrix, and a microcoil array, were developed. The micropost matrix consists of post-shaped electrodes embedded in an insulating layer. With a separate ac voltage applied to each electrode, the micropost matrix generates dielectrophoretic force to trap and move individual biological cells. The microelectromagnet matrix consists of two arrays of straight wires aligned perpendicular to each other, that are covered with insulating layers. By independently controlling the current in each wire, the microelectromagnet matrix creates versatile magnetic fields to manipulate individual biological cells attached to magnetic beads. The microcoil array is a set of coils implemented in a foundry using a standard silicon fabrication technology. Current sources to the coils, and control circuits are integrated on a single chip, making the device self-contained. Versatile manipulation of biological cells was demonstrated using these devices by generating optimized electric or magnetic field patterns. A single yeast cell was trapped and positioned with microscopic resolution, and multiple yeast cells were trapped and independently moved along the separate paths for cell-sorting.

Lee, H.; Hunt, T. P.; Liu, Y.; Ham, D.; Westervelt, R. M.

2005-06-01

160

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

PubMed

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

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

2011-02-28

161

Evaluation of Cyanex 923-coated magnetic particles for the extraction and separation of lanthanides and actinides from nuclear waste streams  

Microsoft Academic Search

In the magnetically assisted chemical separation (MACS) process, tiny ferromagnetic particles coated with solvent extractant are used to selectively separate radionuclides and hazardous metals from aqueous waste streams. The contaminant-loaded particles are then recovered from the waste solutions using a magnetic field. The contaminants attached to the magnetic particles are subsequently removed using a small volume of stripping agent. In

B. S. Shaibu; M. L. P. Reddy; A. Bhattacharyya; V. K. Manchanda

2006-01-01

162

Tevatron electron lens magnetic system  

SciTech Connect

In the framework of collaboration between IHEP and FNAL, a magnetic system of the Tevatron Electron Lens (TEL) has been designed and built. The TEL is currently installed in the superconducting ring of the Tevatron proton-antiproton collider and used for experimental studies of beam-beam compensation [1].

Vladimir Shiltsev et al.

2001-07-12

163

Separation of aqueous two-phase polymer systems in microgravity  

NASA Technical Reports Server (NTRS)

Phase separation of polymer systems in microgravity is studied in aircraft flights to prepare shuttle experiments. Short duration (20 sec) experiments demonstrate that phase separation proceeds rapidly in low gravity despite appreciable phase viscosities and low liquid interfacial tensions (i.e., 50 cP, 10 micro N/m). Ostwald ripening does not appear to be a satisfactory model for the phase separation mechanism. Polymer coated surfaces are evaluated as a means to localize phases separated in low gravity. Contact angle measurements demonstrate that covalently coupling dextran or PEG to glass drastically alters the 1-g wall wetting behavior of the phases in dextran-PEG two phase systems.

Vanalstine, J. M.; Harris, J. M.; Synder, S.; Curreri, P. A.; Bamberger, S. B.; Brooks, D. E.

1984-01-01

164

256-channel magnetic imaging system  

NASA Astrophysics Data System (ADS)

We present the design and fabrication of a magnetoresistive imaging system capable of scanning 256 channels simultaneously along linear ranges of either 4 or 13mm. High speed electronics read the channels and transfer the data to a computer that builds and displays the images. The system was successfully used to image magnetic tapes for real-time forensic validation purposes and can also be applied in other noninvasive imaging applications.

da Silva, F. C. S.; Halloran, S. T.; Kos, A. B.; Pappas, D. P.

2008-01-01

165

[The outlook for human blood component separation and the treatment of cancerous tumors by magnetic methods].  

PubMed

This work presents in brief some expectations related to the solution of certain biomedical problems by using a non-conventional physical method: The high-gradient magnetic separation (HGMS). At first a short presentation of the HGMS method is given and then its application in separation of the human blood components is reported. The up to date intensely studied method with magnetic carriers is then described. Among other things, this method enables the cancer tumors treatment by intracavity radiotherapy, drug targeting, and diagnosis exploration. PMID:10756959

Iacob, G; Ciochin?, A D

1999-01-01

166

Separation and detection of multiple pathogens in a food matrix by magnetic SERS nanoprobes  

Microsoft Academic Search

A rapid and sensitive method was developed here for separation and detection of multiple pathogens in food matrix by magnetic\\u000a surface-enhanced Raman scattering (SERS) nanoprobes. Silica-coated magnetic probes (MNPs@SiO2) of ?100 nm in diameter were first prepared via the reverse microemulsion method using cetyltrimethylammonium bromide as\\u000a a surfactant and tetraethyl orthosilicate as the silica precursor. The as-prepared MNPs@SiO2 were functionalized with

Yuling Wang; Sandeep Ravindranath; Joseph Irudayaraj

2011-01-01

167

Flightweight Electro-Magnet Systems  

NASA Technical Reports Server (NTRS)

NASA has a need for lightweight high performance magnets to be used in propulsion systems involving plasmas. We report the design, construction, and testing of a six inch diameter by twelve inch long solenoid using high purity aluminum wire operating at a temperature of 77 Kelvin (K) for the current carrying element. High purity aluminum is the material of choice because of three properties that make it optimal for magnetic construction. At 77 K high purity aluminum has one of the lowest resistivities at 77 K of any metal (p = 0.254 muOMEGA-cm), thus reducing the power requirements for creating magnetic fields. Aluminum is a low-density (2.6989 g/cc) material and the end product magnet will be of low total mass compared to similar designs involving copper or other elements. The magneto-resistance of aluminum saturates at low magnetic fields and does not increase indefinitely as is the case in copper. The magnet consists of four layers of closely wound wire and is approximately 150 mm in diameter by 300 mm long. A cylinder made from G - 10 was machined with a spiral groove to hold the high purity Al wire and the wire wound on it. Following the winding, each layer was potted in STYCAST high thermal conductivity epoxy to provide insulation between the turns of the coil and mechanical strength. The magneto-resistance of the coil has been measured at the National High Magnetic Field Laboratory (NHMFL), Tallahassee, FL in externally applied fields to 10 tesla. Following these tests it was energized to the full 2 tesla field it can produce using the facilities of the NHMFL at the Los Alamos National Laboratory. The results of all of these tests will be presented.

Goodrich, Roy G.; Litchford, Ron; Robertson, Tony; Schmidt, Dianne; Rodgers, Stephen L. (Technical Monitor)

2001-01-01

168

Toroidal magnet system  

DOEpatents

In a plasma device having a toroidal plasma containment vessel, a toroidal field-generating coil system includes fixed linking coils each formed of first and second sections with the first section passing through a central opening through the containment vessel and the second section completing the linking coil to link the containment vessel. A plurality of removable unlinked coils are each formed of first and second C-shaped sections joined to each other at their open ends with their bights spaced apart. The second C-shaped section of each movable coil is removably mounted adjacent the second section of a linking coil, with the containment vessel disposed between the open ends of the first and second C-shaped sections. Electric current is passed through the linking and removable coils in opposite sense in the respective adjacent second sections to produce a net toroidal field.

Ohkawa, Tihiro (La Jolla, CA); Baker, Charles C. (Naperville, IL)

1981-01-01

169

Superconducting magnet system for RHIC  

SciTech Connect

The proposed Relativistic Heavy Ion Collider (RHIC) will operate at ion energies of 7 to 100/sup +/ GeV/Amu for ions as heavy as Au/sup 197/. This paper discusses the superconducting magnet system for this machine. It will consist of 372 dipoles typically 9.7 meters long with an operating field of 3.4 Tesla, 492 quadrupoles with typical length 1.4 meters, gradient 76 T/m, and approximately 1000 sextupole and corrector magnets. A detailed design has been developed for the dipoles which will have a clear bore of 76 mm; less detailed designs are presented for the other components. A proof-of-concept magnet has been constructed and successfully tested. 3 refs., 5 figs.

Thompson, P.A.; Cottingham, J.; Dahl, P.; Fernow, R.; Garber, M.; Ghosh, A.; Goodzeit, C.; Greene, A.; Hahn, H.; Herrera, J.

1985-01-01

170

Membrane separation systems---A research and development needs assessment  

SciTech Connect

Membrane based separation technology, a relative newcomer on the separations scene, has demonstrated the potential of saving enormous amounts of energy in the processing industries if substituted for conventional separation systems. Over 1 quad annually, out of 2.6, can possibly be saved in liquid-to-gas separations, alone, if membrane separation systems gain wider acceptance, according to a recent DOE/OIP (DOE/NBM-80027730 (1986)) study. In recent years great strides have been made in the field and offer even greater energy savings in the future when substituted for other conventional separation techniques such as distillation, evaporation, filtration, sedimentation, and absorption. An assessment was conducted by a group of six internationally known membrane separations experts who examined the worldwide status of research in the seven major membrane areas. This encompassed four mature technology areas: reverse osmosis, micorfiltration, ultrafiltration, and electrodialysis; two developing areas: gas separation and and pervaporation; and one emerging technology: facilitated transport. Particular attention was paid to identifying the innovative processes currently emerging, and even further improvements which could gain wider acceptance for the more mature membrane technology. The topics that were pointed out as having the greatest research emphasis are pervaporation for organic-organic separations; gas separation; micorfiltration; an oxidant-resistant reverse osmosis membrane; and a fouling-resistant ultrafiltration membrane. 35 refs., 6 figs., 22 tabs.

Baker, R.W. (Membrane Technology and Research, Inc., Menlo Park, CA (USA)); Cussler, E.L. (Minnesota Univ., Minneapolis, MN (USA). Dept. of Chemical Engineering and Materials Science); Eykamp, W. (California Univ., Berkeley, CA (USA)); Koros, W.J. (Texas Univ., Austin, TX (USA)); Riley, R.L. (Separation Systems Technology, San Diego, CA (USA)); Strathmann, H. (Fraunhofer-Institut fuer Grenzflaech

1990-03-01

171

Status of the LHCb magnet system  

E-print Network

The LHCb experiment focuses on the precision measurement of CP violation and rare decays in the B-meson system. It plans to operate with an average luminosity of $2\\times 10^{32}$~cm$^{-2}$s$~^{-1}$, which should be obtained from the beginning of the LHC operation. The LHCb detector exploits the forward region of the pp collisions at the LHC collider. It requires a single-arm spectrometer for the separation and momentum measurement of the charged particles with a large dipole magnet of a free aperture of $\\pm 300$~mrad horizontally and $\\pm 250$~mrad vertically. The magnet is designed for a total integrated field of 4~Tm. The pole gap is 2.2 to 3.5~m vertically (the direction of the field) and 2.6 to 4.2~m horizontally. The overall length of the magnet (in beam direction) is 5~m and its total weight about 1500~t. The power dissipation in the aluminium coils will be 4.2~MW. The magnet yoke is constructed from low carbon steel plates of 100~mm thickness. The maximum weight of one plate does not exceed 25~t. The...

André, J; Flegel, W; Giudici, P A; Jamet, O; Lançon, P; Losasso, M; Röhner, F; Rosset, C

2002-01-01

172

Design and synthesis of reactive separation systems  

SciTech Connect

During the last decade there has been a rapid upturn in interest in reactive distillation. The chemical process industry recognizes the favorable economics of carrying out reaction simultaneously with distillation for certain classes of reacting systems, and many new processes have been built based on this technology. Interest is also increasing by academics and software vendors. Systematic design methods for reactive distillation systems have only recently begun to emerge. In this report we survey the available design techniques and point out the contributions made by our group at the University of Massachusetts.

Doherty, M.F.

1992-01-01

173

Separating Data and Control Transfer in Distributed Operating Systems  

E-print Network

Separating Data and Control Transfer in Distributed Operating Systems Abstract Chandramohan A compared to current LANs such as Eth- ernet. We believe that these new network and processor technologies, directly supported by the communication model, is the separation of data transfer and con- td transfer

Goldstein, Seth Copen

174

The Appell hypergeometric functions and classical separable mechanical systems  

Microsoft Academic Search

A relationship between two old mathematical subjects is observed: the theory of hypergeometric functions and the separability in classical mechanics. Separable potential perturbations of the integrable billiard systems and the Jacobi problem for geodesics on an ellipsoid are expressed through the Appell hypergeometric functions $F_4$ of two variables. Even when the number of degrees of freedom increases, if an ellipsoid

Vladimir Dragovic

2000-01-01

175

Scanner system for separate-sided lumber surface measurements  

Microsoft Academic Search

A novel scanner system is presented that is able to separately measure the surface height profile of each side of a piece of lum- ber while moving longitudinally in a sawmill. Such measure- ments are very useful for product quality control. In addition, be- cause each side of the lumber is typically cut by a different tool, separate surface measurements

Gary S. Schajer; Javier I. Gazzarri; Darrell C. Wong; Thomas C. Maness; Robert A. Kozak

176

Separation and enrichment of enantiopure from racemic compounds using magnetic levitation.  

PubMed

Crystallization of a solution with high enantiomeric excess can generate a mixture of crystals of the desired enantiomer and the racemic compound. Using a mixture of S-/RS-ibuprofen crystals as a model, we demonstrated that magnetic levitation (MagLev) is a useful technique for analysis, separation and enantioenrichment of chiral/racemic products. PMID:24875274

Yang, Xiaochuan; Wong, Shin Yee; Bwambok, David K; Atkinson, Manza B J; Zhang, Xi; Whitesides, George M; Myerson, Allan S

2014-07-18

177

Magnetic separation of colloidal nanoparticle mixtures using a material specific peptide.  

PubMed

A material specific peptide bound to Fe2O3 facilitates the selective sequestration of Au from a colloidal mixture of Au and CdS nanoparticles; the Au-Fe2O3 precipitate can then be magnetically separated from the colloidal CdS, and the Au nanoparticles can be recovered upon release from the Fe2O3. PMID:23661051

Essinger-Hileman, Elizabeth R; Popczun, Eric J; Schaak, Raymond E

2013-06-18

178

APPLICATION OF HIGH-GRADIENT MAGNETIC SEPARATION TO FINE PARTICLE CONTROL  

EPA Science Inventory

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...

179

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

SciTech Connect

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-inertia being part of finite electron Larmor radius effects, which increase downstream and eventually demagnetize the plasma. Current ambipolarity is not fulfilled and ion separation can be either outwards or inwards of magnetic streamtubes, depending on their magnetization. Electron separation penalizes slightly the plume efficiency and is larger for plasma beams injected with large pressure gradients. An alternative nonzero electron-inertia model [E. Hooper, J. Propul. Power 9, 757 (1993)] based on cold plasmas and current ambipolarity, which predicts inwards electron separation, is discussed critically. A possible competition of the gyroviscous force with electron-inertia effects is commented briefly.

Ahedo, Eduardo; Merino, Mario [Universidad Politecnica de Madrid, 28040 Madrid (Spain)

2012-08-15

180

Aqueous two-phase systems for protein separation: phase separation and applications.  

PubMed

Aqueous two-phase systems (ATPS) that are formed by mixing a polymer (usually polyethylene glycol, PEG) and a salt (e.g. phosphate, sulphate or citrate) or two polymers, and water can be effectively used for the separation and purification of proteins. The partitioning between both phases is dependent on the surface properties of the proteins and on the composition of the two phase system as has been recently reviewed by Asenjo and Andrews [1]. This paper analyses and reviews some elements that are important for implementation of these processes which are related to phase separation and continuous processing of ATPS. Phase separation for ATPS formed by PEG and salts has been studied and has been found to depend on which of the phases is continuous. Profiles of dispersion heights can be represented as a fraction of the initial height and are independent of the dimensions of the separator. This is important for the design of large scale aqueous two-phase separations. The kinetics of phase separation has been investigated as a function of the physical properties of the system. The settling rate is a crucial parameter for equipment design and it has been studied as a function of viscosity and density of the phases as well as the interfacial tension between them. Correlations that describe the rate of phase separation have been developed. Working in a continuous bottom-phase region is advantageous to ensure fast separation. A mathematical model to describe the continuous, study state operation of these systems has been investigated. Two simulations to show the effect of phase ratio on purification have been carried out which clearly show the effectivity of using such models. The practical application of ATPS has been demonstrated in many cases including a number of industrial applications with excellent levels of purity and yield. Examples include the purification of ?-amylase and the large scale "in situ" purification of IGF-1 carried out by Genentech. The production scale purification of chymosin from recombinant Aspergillus supernatant is the most successful industrial application of this technology. Other applications include the separation and purification of human ?-antitrypsin from transgenic sheep milk, the purification of monoclonal antibodies, tPA from CHO supernatant and recombinant VLPs (virus like particles) from yeast cells. PMID:22494642

Asenjo, Juan A; Andrews, Barbara A

2012-05-18

181

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

NASA Astrophysics Data System (ADS)

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.

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

2010-11-01

182

In situ magnetic separation of antibody fragments from Escherichia coli in complex media  

PubMed Central

Background In situ magnetic separation (ISMS) has emerged as a powerful tool to overcome process constraints such as product degradation or inhibition of target production. In the present work, an integrated ISMS process was established for the production of his-tagged single chain fragment variable (scFv) D1.3 antibodies (“D1.3”) produced by E. coli in complex media. This study investigates the impact of ISMS on the overall product yield as well as its biocompatibility with the bioprocess when metal-chelate and triazine-functionalized magnetic beads were used. Results Both particle systems are well suited for separation of D1.3 during cultivation. While the triazine beads did not negatively impact the bioprocess, the application of metal-chelate particles caused leakage of divalent copper ions in the medium. After the ISMS step, elevated copper concentrations above 120 mg/L in the medium negatively influenced D1.3 production. Due to the stable nature of the model protein scFv D1.3 in the biosuspension, the application of ISMS could not increase the overall D1.3 yield as was shown by simulation and experiments. Conclusions We could demonstrate that triazine-functionalized beads are a suitable low-cost alternative to selectively adsorb D1.3 fragments, and measured maximum loads of 0.08 g D1.3 per g of beads. Although copper-loaded metal-chelate beads did adsorb his-tagged D1.3 well during cultivation, this particle system must be optimized by minimizing metal leakage from the beads in order to avoid negative inhibitory effects on growth of the microorganisms and target production. Hereby, other types of metal chelate complexes should be tested to demonstrate biocompatibility. Such optimized particle systems can be regarded as ISMS platform technology, especially for the production of antibodies and their fragments with low stability in the medium. The proposed model can be applied to design future ISMS experiments in order to maximize the overall product yield while the amount of particles being used is minimized as well as the number of required ISMS steps. PMID:23688064

2013-01-01

183

21 CFR 882.5805 - Repetitive transcranial magnetic stimulation system.  

Code of Federal Regulations, 2012 CFR

... false Repetitive transcranial magnetic stimulation system. 882.5805...5805 Repetitive transcranial magnetic stimulation system. (a) Identification. A repetitive transcranial magnetic stimulation system is an...

2012-04-01

184

21 CFR 882.5805 - Repetitive transcranial magnetic stimulation system.  

Code of Federal Regulations, 2013 CFR

... false Repetitive transcranial magnetic stimulation system. 882.5805...5805 Repetitive transcranial magnetic stimulation system. (a) Identification. A repetitive transcranial magnetic stimulation system is an...

2013-04-01

185

21 CFR 882.5805 - Repetitive transcranial magnetic stimulation system.  

... false Repetitive transcranial magnetic stimulation system. 882.5805...5805 Repetitive transcranial magnetic stimulation system. (a) Identification. A repetitive transcranial magnetic stimulation system is an...

2014-04-01

186

Theory of separation phenomena in strongly-correlated electron systems  

Microsoft Academic Search

We present a coherent gauge-theoretical interpretation of various possible separation phenomena of strongly-correlated electron\\u000a systems. The typical examples are (i) charge-spin separation (CSS) in the t-J model of high-Tc superconductivity, and (ii)\\u000a particle-flux separation (PFS) in the quantum Hall effect atv=1\\/2. By introducing auxiliary gauge fields, we map the system into an effective U(1) lattice gauge theory. It exhibits a

Ikuo Ichinose; Tetsuo Matsui

1996-01-01

187

Magnetic field exposure and behavioral monitoring system.  

PubMed

To maximize the availability and usefulness of a small magnetic field exposure laboratory, we designed a magnetic field exposure system that has been used to test human subjects, caged or confined animals, and cell cultures. The magnetic field exposure system consists of three orthogonal pairs of coils 2 m square x 1 m separation, 1.751 m x 0.875 m separation, and 1.5 m x 0.75 m separation. Each coil consisted of ten turns of insulated 8 gauge stranded copper conductor. Each of the pairs were driven by a constant-current amplifier via digital to analog (D/A) converter. A 9 pole zero-gain active Bessel low-pass filter (1 kHz corner frequency) before the amplifier input attenuated the expected high frequencies generated by the D/A conversion. The magnetic field was monitored with a 3D fluxgate magnetometer (0-3 kHz, +/- 1 mT) through an analog to digital converter. Behavioral monitoring utilized two monochrome video cameras (viewing the coil center vertically and horizontally), both of which could be video recorded and real-time digitally Moving Picture Experts Group (MPEG) encoded to CD-ROM. Human postural sway (standing balance) was monitored with a 3D forceplate mounted on the floor, connected to an analog to digital converter. Lighting was provided by 12 offset overhead dimmable fluorescent track lights and monitored using a digitally connected spectroradiometer. The dc resistance, inductance of each coil pair connected in series were 1.5 m coil (0.27 Omega, 1.2 mH), 1.75 m coil (0.32 Omega, 1.4 mH), and 2 m coil (0.38 Omega, 1.6 mH). The frequency response of the 1.5 m coil set was 500 Hz at +/- 463 microT, 1 kHz at +/- 232 microT, 150 micros rise time from -200 microT(pk) to + 200 microT(pk) (square wave) and is limited by the maximum voltage ( +/- 146 V) of the amplifier (Bessel filter bypassed). PMID:11536281

Thomas, A W; Drost, D J; Prato, F S

2001-09-01

188

?-Detected NMR Search for Magnetic Phase Separation in Epitaxial GaAs:Mn  

NASA Astrophysics Data System (ADS)

To test for the microscopic magnetic phase separation in the dilute magnetic semiconductor Ga1-xMnxAs sug-gested by low energy muon spin rotation measurements[1], we present a detailed analysis of the amplitudes of the 8Li ?-detected nuclear magnetic resonance in an epitaxially grown thin film of x = 5.4% Mn doped GaAs on a semi-insulating GaAs substrate with magnetic transition temperature TC =72 K. The spectrum at 100 K corresponds to 73% of the full room temperature amplitude, and at 60 K to about 62%. The 11% loss of signal through the magnetic tran-sition is much smaller than that ? 50% found by low energy ?SR[1], and may be entirely due to an amplitude change intrinsic to GaAs. This lack of evidence for phase separation is, however, consistent with the full volume fraction magnetism found by a second low energy ?SR measurement on a different sample using weak transverse field[2].

Song, Q.; Chow, K. H.; Miller, R. I.; Fan, I.; Hossain, M. D.; Kiefl, R. F.; Morris, G. D.; Kreitzman, S. R.; Levy, C. D. P.; Parolin, T. J.; Pearson, M. R.; Salman, Z.; Saadaoui, H.; Smadella, M.; Wang, D.; Yu, K. M.; Liu, X.; Furdyna, J. K.; MacFarlane, W. A.

189

Isolation of Osteoprogenitors from Human Jaw Periosteal Cells: A Comparison of Two Magnetic Separation Methods  

PubMed Central

Human jaw periosteum tissue contains osteoprogenitors that have potential for tissue engineering applications in oral and maxillofacial surgeries. To isolate osteoprogenitor cells from heterogeneous cell populations, we used the specific mesenchymal stem cell antigen-1 (MSCA-1) antibody and compared two magnetic separation methods. We analyzed the obtained MSCA-1+ and MSCA-1? fractions in terms of purity, yield of positive/negative cells and proliferative and mineralization potentials. The analysis of cell viability after separation revealed that the EasySep method yielded higher viability rates, whereas the flow cytometry results showed a higher purity for the MACS-separated cell fractions. The mineralization capacity of the osteogenic induced MSCA-1+ cells compared with the MSCA-1? controls using MACS was 5-fold higher, whereas the same comparison after EasySep showed no significant differences between both fractions. By analyzing cell proliferation, we detected a significant difference between the proliferative potential of the osteogenic cells versus untreated cells after the MACS and EasySep separations. The differentiated cells after MACS separation adjusted their proliferative capacity, whereas the EasySep-separated cells failed to do so. The protein expression analysis showed small differences between the two separation methods. Our findings suggest that MACS is a more suitable separation method to isolate osteoprogenitors from the entire jaw periosteal cell population. PMID:23094035

Olbrich, Marcus; Rieger, Melanie; Reinert, Siegmar; Alexander, Dorothea

2012-01-01

190

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

SciTech Connect

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.

Kaur, Maninder [Idaho Univ., Moscow, ID (United States); Johnson, Andrew [Idaho Univ., Moscow, ID (United States); Tian, Guoxin [Lawrence Berkeley National Laboratory (LBNL), Berkeley, CA (United States); Jiang, Weilin [Pacific Northwest National Laboratory (PNNL), Richland, WA (United States); Rao, Linfeng [Lawrence Berkeley National Laboratory (LBNL), Berkeley, CA (United States); Paszczynski, Andrzej [Idaho Univ., Moscow, ID (United States); Qiang, You [Center for Advanced Energy Studies, Idaho Falls, ID (United States); Idaho Univ., Moscow, ID (United States)

2013-01-15

191

Magnetic Field Separation Around Planets Using an Adjoint-Method Approach  

NASA Astrophysics Data System (ADS)

The two spacecraft of the BepiColombo mission will reach planet Mercury in 2022. The magnetometers on-board these polar orbiting spacecraft will provide a detailed map of the magnetic field in Mercury's environment. Unfortunately, a separation of the magnetic field into internal and external parts using the classical Gauss-algorithm is not possible due to strong electric currents in the orbit region of the spacecraft. These currents are due to the interaction of the solar wind with Mercury's planetary magnetic field. We use an MHD code to simulate this interaction process. This requires a first choice of Mercury's planetary field which is used and modified until the simulation results fit to the actual measurements. This optimization process is carried out most efficiently using an adjoint-method. The adjoint-method is well known for its low computational cost in order to determine sensitivities required for the minimization. In a first step, the validity of our approach to separate magnetic field contributions into internal and external parts is demonstrated using synthetic generated data. Furthermore, we apply our approach to satellite measurements of the Earth's magnetic field. We can compare the results with the well known planetary field of the Earth to prove practical suitability.

Nabert, Christian; Glassmeier, Karl-Heinz; Heyner, Daniel; Othmer, Carsten

192

Flat minimal quantizations of Stäckel systems and quantum separability  

NASA Astrophysics Data System (ADS)

In this paper, we consider the problem of quantization of classical Stäckel systems and the problem of separability of related quantum Hamiltonians. First, using the concept of Stäckel transform, natural Hamiltonian systems from a given Riemann space are expressed by some flat coordinates of related Euclidean configuration space. Then, the so-called flat minimal quantization procedure is applied in order to construct an appropriate Hermitian operator in the respective Hilbert space. Finally, we distinguish a class of Stäckel systems which remains separable after any of admissible flat minimal quantizations.

B?aszak, Maciej; Doma?ski, Ziemowit; Silindir, Burcu

2014-12-01

193

Preparation of thermosensitive polymer magnetic particles and their application in protein separations.  

PubMed

This paper presents a kind of thermoresponsive polymeric magnetic particles for protein separations. The magnetofluids were directly encapsulated in hollow particles constructed by self-assembly of rod-coil poly(ethylene glycol)-poly(N-isopropylacrylamide)/?-cyclodextrin (PEG-PNIPAM/?-CD) complexes. The resulting particles showed reversible protein absorption/desorption capacity because the reversible thermo-sensitivity of PNIPAM. Above the lower critical solution temperature (LCST) of PNIPAM, these particles showed high absorptive capacities and adsorption was done at lower temperature. The protein-laden particles are readily removed from the feed solution in a magnetic field. PMID:25222511

Luo, Ling; Zhang, Hong-Su; Liu, Yan; Ha, Wei; Li, Luo-Hao; Gong, Xiao-Lei; Li, Bang-Jing; Zhang, Sheng

2014-12-01

194

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

SciTech Connect

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 (K{sub d}) values for stimulant tank waste were obtained. Further studies demonstrated that the large partitioning was due to uncoated particles.

Bauer, C.B.; Rogers, R.D. [Northern Illinois Univ., De Kalb, IL (United States). Dept. of Chemistry; Nunez, L.; Ziemer, M.D.; Pleune, T.T.; Vandegrift, G.F. [Argonne National Lab., IL (United States)

1995-11-01

195

Just in Time-Selection: A Rapid Semiautomated SELEX of DNA Aptamers Using Magnetic Separation and BEAMing.  

PubMed

A semiautomated two-step method for in vitro selection of DNA aptamers using magnetic separation and solid-phase emulsion polymerase chain reaction has been developed. The application of a magnetic separator allows the simultaneous processing of up to 12 SELEXs (systematic evolution of ligands by exponential enrichment) with different targets or buffer conditions. Using a magnetic separator and covalent target immobilization on magnetic beads, the selection process was simplified and the substeps of aptamer/target incubation, washing, and elution of the aptamers were merged into one automated procedure called "FISHing". Without further processing the resulting FISHing eluates are suitable for BEAMing (beads, emulsion, amplification, and magnetics), which includes the amplification by emPCR (emulsion polymerase chain reaction) and strand separation by the implementation of covalently immobilized reverse primers on magnetic beads. The novel selection process has been proved and validated by selecting and characterization of aptamers to the wine fining agent lysozyme. PMID:25286022

Hünniger, Tim; Wessels, Hauke; Fischer, Christin; Paschke-Kratzin, Angelika; Fischer, Markus

2014-11-01

196

Inertial waste separation system for zero G WMS  

NASA Technical Reports Server (NTRS)

The design, operation, and flight test are presented for an inertial waste separation system. Training personnel to use this system under simulated conditions is also discussed. Conclusions indicate that before the system is usable in zero gravity environments, a mirror for the user's guidance should be installed, the bounce cycle and bag changing system should be redesigned, and flange clips should be added to improve the user's balance.

1971-01-01

197

Development of portable superconducting bulk magnet system  

NASA Astrophysics Data System (ADS)

Recently a magnetic drug delivery system (MDDS) has been developing to navigate magnetic seeded drugs around diseased parts of the human body. To improve the magnetic drug delivery performance, a portable high temperature superconducting (HTS) bulk magnet system with high magnetic fields has been developed. This magnet system mainly consists of small bulk high temperature superconductors and a compact cryocooler. The materials of the high temperature superconductor are rare earth 123 single domain compounds (Gd-Ba-Cu-O). The bulk magnet was activated successfully using field-cooling magnetization under the superconducting solenoid magnet. The magnetic flux densities at the surface of the vacuum chambers that contain bulk magnets reached 5.07 T and 6.76 T using the static magnetic fields of 6 T and 10 T superconducting solenoid magnets, respectively. A cryocooler cooled them to 38.1 K and 39.1 K. It was clarified that the magnetic gradient was approximately 10 T/m at a position located 50 mm from the surface of the vacuum chambers.

Saho, N.; Nishijima, N.; Tanaka, H.; Sasaki, A.

2009-10-01

198

Development of magnetic force modeling equipment for magnetic levitation system  

Microsoft Academic Search

In this paper, we propose a modeling equipment that obtains every equilibrium point of a magnetic levitation system automatically. To obtain every equilibrium point, we develop an automatic modeling equipment that measures the magnetic force exerted on the levitation object, the coil current of electromagnet, and the distance between the levitation object and the electromagnet. The modeling equipment is composed

Ji-Hyuk Yang; Young-Sam Lee; Oh-Kyu Kwon

2010-01-01

199

A magnetic suspension system with a large angular range  

NASA Technical Reports Server (NTRS)

The paper describes a small-scale laboratory system, called the Large-Angle Magnetic Suspension Test Fixture (LAMSTF), constructed at NASA Langley Research Center in order to explore and develop technology required for the magnetic suspension of objects over large ranges of orientation. The LAMSTF hardware comprises five electromagnets in a circular arrangement, each driven from a separate bipolar power amplifier. The suspended element is a cylindrical axially magnetized permanent magnet core, within an aluminum tube. The element, which is 'levitated' by repulsive forces, is stabilized in five degrees-of-freedom, with rotation about the cylinder axis not controlled. The controller accommodates the changes in magnetic coupling between the electromagnets and the suspended element by real-time adaptation of a decoupling matrix. The paper presents performance measurements demonstrating that the major design objective of the 360 deg rotation was accomplished.

Britcher, Colin P.; Ghofrani, Mehran

1993-01-01

200

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

PubMed

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

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

2013-10-01

201

Computational Analysis of Enhanced Magnetic Bioseparation in Microfluidic Systems with Flow-Invasive Magnetic Elements  

NASA Astrophysics Data System (ADS)

A microfluidic design is proposed for realizing greatly enhanced separation of magnetically-labeled bioparticles using integrated soft-magnetic elements. The elements are fixed and intersect the carrier fluid (flow-invasive) with their length transverse to the flow. They are magnetized using a bias field to produce a particle capture force. Multiple stair-step elements are used to provide efficient capture throughout the entire flow channel. This is in contrast to conventional systems wherein the elements are integrated into the walls of the channel, which restricts efficient capture to limited regions of the channel due to the short range nature of the magnetic force. This severely limits the channel size and hence throughput. Flow-invasive elements overcome this limitation and enable microfluidic bioseparation systems with superior scalability. This enhanced functionality is quantified for the first time using a computational model that accounts for the dominant mechanisms of particle transport including fully-coupled particle-fluid momentum transfer.

Khashan, S. A.; Alazzam, A.; Furlani, E. P.

2014-06-01

202

SERS-Fluorescence Joint Spectral Encoded Magnetic Nanoprobes for Multiplex Cancer Cell Separation.  

PubMed

A new kind of cancer cell separation method is demonstrated, using surface-enhanced Raman scattering (SERS) and fluorescence dual-encoded magnetic nanoprobes. The designed nanoprobes can realize SERS-fluorescence joint spectral encoding (SFJSE) and greatly improve the multiplexing ability. The nanoprobes have four main components, that is, the magnetic core, SERS generator, fluorescent agent, and targeting antibody. These components are assembled with a multi-layered structure to form the nanoprobes. Specifically, silica-coated magnetic nanobeads (MBs) are used as the inner core. Au core-Ag shell nanorods (Au@Ag NRs) are employed as the SERS generators and attached on the silica-coated MBs. After burying these Au@Ag NRs with another silica layer, CdTe quantum dots (QDs), that is, the fluorescent agent, are anchored onto the silica layer. Finally, antibodies are covalently linked to CdTe QDs. SFJSE is fulfilled by using different Raman molecules and QDs with different emission wavelengths. By utilizing four human cancer cell lines and one normal cell line as the model cells, the nanoprobes can specifically and simultaneously separate target cancer cells from the normal ones. This SFJSE-based method greatly facilitates the multiplex, rapid, and accurate cancer cell separation, and has a prosperous potential in high-throughput analysis and cancer diagnosis. PMID:24862088

Wang, Zhuyuan; Zong, Shenfei; Chen, Hui; Wang, Chunlei; Xu, Shuhong; Cui, Yiping

2014-11-01

203

Study on a novel POM-based magnetic photocatalyst: Photocatalytic degradation and magnetic separation  

Microsoft Academic Search

The photocatalytic performance of a novel polyoxometalate (POM)-based magnetic photocatalyst was studied by photocatalytic degradation of a model compound (formic acid) in an annular fluidized bed photoreactor. Degradation rate, apparent quantum efficiency, and energy efficiency were evaluated and compared with suspended TiO2 fine particles (Degussa P25) and quartz sand supported TiO2 photocatalysts. All degradation experiments were conducted under fully irradiated

Wei Qiu; Ying Zheng; Katy A. Haralampides

2007-01-01

204

Detection of Cronobacter species in powdered infant formula by probe-magnetic separation PCR.  

PubMed

Cronobacter species are opportunistic foodborne pathogens associated with serious infections in preterm neonates and infants. Based on the epidemiological research, infant formula products are considered to be the main source of infections from this organism. Therefore, accurate methods are required for detection of Cronobacter species. In this study, the specific probe and primers for detection of this organism were designed and verified. The probe-magnetic beads were prepared for sequence capture, followed by PCR assay to detect the target gene. This probe-magnetic separation PCR assay could detect as few as 10(3) cfu/mL of Cronobacter in artificially contaminated infant formulas in less than 4 h. The combination of magnetic beads and PCR showed the potential for the detection of Cronobacter in infant formulas and may have applications in the dairy industry. PMID:25108865

Xu, Feng; Li, Peng; Ming, Xing; Yang, Dong; Xu, Hengyi; Wu, Xiaoli; Shah, Nagendra P; Wei, Hua

2014-10-01

205

Conjugates of magnetic nanoparticle-actinide specific chelator for radioactive waste separation.  

PubMed

A novel nanotechnology for the separation of radioactive waste that uses magnetic nanoparticles (MNPs) conjugated with actinide specific chelators (MNP-Che) is reviewed with a focus on design and process development. The MNP-Che separation process is an effective way of separating heat generating minor actinides (Np, Am, Cm) from spent nuclear fuel solution to reduce the radiological hazard. It utilizes coated MNPs to selectively adsorb the contaminants onto their surfaces, after which the loaded particles are collected using a magnetic field. The MNP-Che conjugates can be recycled by stripping contaminates into a separate, smaller volume of solution, and then become the final waste form for disposal after reusing number of times. Due to the highly selective chelators, this remediation method could be both simple and versatile while allowing the valuable actinides to be recovered and recycled. Key issues standing in the way of large-scale application are stability of the conjugates and their dispersion in solution to maintain their unique properties, especially large surface area, of MNPs. With substantial research progress made on MNPs and their surface functionalization, as well as development of environmentally benign chelators, this method could become very flexible and cost-effective for recycling used fuel. Finally, the development of this nanotechnology is summarized and its future direction is discussed. PMID:24070142

Kaur, Maninder; Zhang, Huijin; Martin, Leigh; Todd, Terry; Qiang, You

2013-11-01

206

Conjugates of Magnetic Nanoparticle -- Actinide Specific Chelator for Radioactive Waste Separation  

SciTech Connect

A novel nanotechnology for the separation of radioactive waste that uses magnetic nanoparticles (MNPs) conjugated with actinide specific chelators (MNP-Che) is reviewed with a focus on design and process development. The MNP-Che separation process is an effective way of separating heat generating minor actinides (Np, Am, Cm) from spent nuclear fuel solution to reduce the radiological hazard. It utilizes coated MNPs to selectively adsorb the contaminants onto their surfaces, after which the loaded particles are collected using a magnetic field. The MNP-Che conjugates can be recycled by stripping contaminates into a separate, smaller volume of solution, and then become the final waste form for disposal after reusing number of times. Due to the highly selective chelators, this remediation method could be both simple and versatile while allowing the valuable actinides to be recovered and recycled. Key issues standing in the way of large-scale application are stability of the conjugates and their dispersion in solution to maintain their unique properties, especially large surface area, of MNPs. With substantial research progress made on MNPs and their surface functionalization, as well as development of environmentally benign chelators, this method could become very flexible and cost-effective for recycling used fuel. Finally, the development of this nanotechnology is summarized and its future direction is discussed.

Maninder Kaur; Huijin Zhang; Leigh Martin; Terry Todd; You Qiang

2013-11-01

207

Magnetic QCA systems G.H. Bernsteina,  

E-print Network

Magnetic QCA systems G.H. Bernsteina, *, A. Imrea , V. Metlushkoc , A. Orlova , L. Zhoua , L. Jia in an altogether new paradigm. Magnetic interactions between nanomagnets are sufficiently strong to allow room recent work of the Notre Dame group on magnetically coupled QCA. q 2005 Elsevier Ltd. All rights reserved

Metlushko, Vitali

208

Vision System Development Through Separation of Management and Processing  

E-print Network

Vision System Development Through Separation of Management and Processing Amir Afrah, Gregor Miller aspects of vision-based sys- tem development that are not fully exploited in current frame- works frameworks, we relate these shortcomings to the lack of systematic classification of sub-tasks in vision

British Columbia, University of

209

SEPARATION OF CONVECTIVE AND STRATIFORM PRECIPITATION IN MESOSCALE SYSTEMS  

E-print Network

of the vertical air motion relative to the fallspeed of ice particles. The precipitation process in most deep. Stratiform precipitation may therefore be defined as a process in which the vertical air motion is generallyPage 1 SEPARATION OF CONVECTIVE AND STRATIFORM PRECIPITATION IN MESOSCALE SYSTEMS NIMBOSTRATUS

Houze Jr., Robert A.

210

Contactless electrical energy transmission system using separable transformer  

Microsoft Academic Search

Contactless electrical energy transmission becomes more and more attractive for different applications. In this system, the design of the separable transformer is very important. The paper uses the mutual inductance model to analyze the coupling ability of the primary coil and the secondary coil. The investigations are carried out by means of ANSYS simulation and measurements. Through analysis, four factors

Zhang Bingyi; Liu Hongbin; Zhao Yisong; Ying Yong; Feng Guihong

2005-01-01

211

Separation of synthetic food colourants in the mixed micellar system  

Microsoft Academic Search

The paper presents a rapid method for the determination of commonly used synthetic food dyes by micellar electrokinetic capillary chromatography. Detection and separation conditions allowing complete resolution of 15 synthetic food colourants were investigated. The effect of different surfactants on the analytes mobility in relation to their structure was tested. After optimization procedure a dual micellar system was selected. All

Ma?gorzata Jaworska; Zofia Szuli?ska; Ma?gorzata Wilk; El?bieta Anuszewska

2005-01-01

212

Swing-out rail system separates overhead crane rails  

NASA Technical Reports Server (NTRS)

Swing-out rail system separates and reconnects the overhead traveling crane rails of a building to provide for the passage of a thick concrete radiation shield sliding door through the rails. In the swing-out position, the rail cantilevered from an axial shaft.

Pitkin, R. G.

1966-01-01

213

A Reverse Osmosis System for an Advanced Separation Process Laboratory.  

ERIC Educational Resources Information Center

Focuses on the development of a pilot unit for use in an advanced separations process laboratory in an effort to develop experiments on such processes as reverse osmosis, ultrafiltration, adsorption, and chromatography. Discusses reverse osmosis principles, the experimental system design, and some experimental studies. (TW)

Slater, C. S.; Paccione, J. D.

1987-01-01

214

The design of an isotope separation system for JET  

SciTech Connect

Cryogenic distillation is planned as one of the processes to be used for isotope separation at JET. Three possible configurations of columns for this service are presented and discussed. The ability to easily control a system of columns must weigh heavily in the final selection of a process for construction. 5 refs., 6 figs., 6 tabs.

Sherman, R.H.

1987-10-01

215

A lysozyme and magnetic bead based method of separating intact bacteria.  

PubMed

As a response to environmental stress, bacterial cells can enter a physiological state called viable but noncultivable (VBNC). In this state, bacteria fail to grow on routine bacteriological media. Consequently, standard methods of contamination detection based on bacteria cultivation fail. Although they are not growing, the cells are still alive and are able to reactivate their metabolism. The VBNC state and low bacterial densities are big challenges for cultivation-based pathogen detection in drinking water and the food industry, for example. In this context, a new molecular-biological separation method for bacteria using point-mutated lysozymes immobilised on magnetic beads for separating bacteria is described. The immobilised mutated lysozymes on magnetic beads serve as bait for the specific capture of bacteria from complex matrices or water due to their remaining affinity for bacterial cell wall components. Beads with bacteria can be separated using magnetic racks. To avoid bacterial cell lysis by the lysozymes, the protein was mutated at amino acid position 35, leading to the exchange of the catalytic glutamate for alanine (LysE35A) and glutamine (LysE35Q). As proved by turbidity assay with reference bacteria, the muramidase activity was knocked out. The mutated constructs were expressed by the yeast Pichia pastoris and secreted into expression medium. Protein enrichment and purification were carried out by SO(3)-functionalised nanoscale cationic exchanger particles. For a proof of principle, the proteins were biotinylated and immobilised on streptavidin-functionalised, fluorescence dye-labelled magnetic beads. These constructs were used for the successful capture of Syto9-marked Microccocus luteus cells from cell suspension, as visualised by fluorescence microscopy, which confirmed the success of the strategy. PMID:21574057

Diler, Ebru; Obst, Ursula; Schmitz, Katja; Schwartz, Thomas

2011-07-01

216

Capture and separation of biomolecules using magnetic beads in a simple microfluidic channel without an external flow device.  

PubMed

The use of microfluidic devices and magnetic beads for applications in biotechnology has been extensively explored over the past decade. Many elaborate microfluidic chips have been used in efficient systems for biological assays. However most fail to achieve the ideal point of care (POC) status, as they require larger conventional external devices in conjunction with the microchip. This paper presents a simple technique to capture and separate biomolecules using magnetic bead movement on a microchip without the use of an external flow device. This microchip consisted of two well reservoirs (W1 and W2) connected via a tapered microchannel. Beads were dragged through the microchannel between the two wells at an equivalent speed to a permanent magnet that moved alongside the microchip. More than 95% of beads were transferred from W1 to W2 within 2 min at an average velocity of 0.7 mm s(-1). Enzymatic reactions were employed to test our microchip. Specifically, three assays were performed using the streptavidin coated magnetic beads as a solid support to capture and transfer biomolecules: (1) non-specific adsorption of the substrate, 6-8-difluoro-4-methylumbelliferyl phosphate (DiFMUP), (2) capture of the enzyme, biotinylated alkaline phosphatase (AP), and (3) separation of AP from DiFMUP. Our non-specific adsorption assay indicated that the microchip was capable of transferring the beads with less than 0.002% carryover of DiFMUP. Our capture assay indicated efficient capture and transfer of AP with beads to W2 containing DiFMUP, where the transferred AP converted 100% of DiFMUP to DiFMU within 15 minutes. Our separation assay showed effective separation of AP from DiFMUP and elucidated the binding capacity of the beads for AP. The leftover unbound AP in W1 converted 100% of DiFMUP within 10 minutes and samples with less than the full bead capacity of AP (i.e. all AP was transferred) did not convert any of the DiFMUP. The immobilization of AP on the bead surface resulted in 32% reduced enzymatic speed compared to that of free AP in solution, as a result of altered protein conformation and/or steric hindrance of the catalytic site. Overall, this microfluidic platform was established as a simple, efficient and effective approach for separating biomolecules without any flow apparatus. PMID:24051541

Wang, Jingjing; Morabito, Kenneth; Erkers, Tom; Tripathi, Anubhav

2013-11-01

217

Hybrid membrane--PSA system for separating oxygen from air  

DOEpatents

A portable, non-cryogenic, oxygen generation system capable of delivering oxygen gas at purities greater than 98% and flow rates of 15 L/min or more is described. The system consists of two major components. The first component is a high efficiency membrane capable of separating argon and a portion of the nitrogen content from air, yielding an oxygen-enriched permeate flow. This is then fed to the second component, a pressure swing adsorption (PSA) unit utilizing a commercially available, but specifically formulated zeolite compound to remove the remainder of the nitrogen from the flow. The system is a unique gas separation system that can operate at ambient temperatures, for producing high purity oxygen for various applications (medical, refining, chemical production, enhanced combustion, fuel cells, etc . . . ) and represents a significant advance compared to current technologies.

Staiger, Chad L. (Albuquerque, NM); Vaughn, Mark R. (Albuquerque, NM); Miller, A. Keith (Albuquerque, NM); Cornelius, Christopher J. (Blackburg, VA)

2011-01-25

218

Dual Fan Separator within the Universal Waste Management System  

NASA Technical Reports Server (NTRS)

Since NASA's new spacecraft in development for both LEO and Deep Space capability have considerable crew volume reduction in comparison to the Space Shuttle, it is clear that NASA requires a smaller and less expensive commode. The UTAS Universal Waste Management System (UWMS) was designed to address these new constraints, resulting in an 80% volume reduction in the cabin while enhancing performance. Whereas all of the current space commodes use air flow to capture both urine and feces and separate air from the captured air/urine mixture, the UWMS commode and urine fans and the urine separator were combined into a single unit. This unit enables use of a single motor and motor controller, which provides considerable packaging and weight efficiency. In some of the intended platform applications for the UWMS, the urine is pumped to a water reclamation system. The ISS Urine Processor Assembly (UPA) system requires delivered urine to include less than 0.25% air inclusion. Air inclusion in centrifugal urine separators is greatly dependent on its rotational speed. To satisfy this requirement, a gear reducer was included, allowing the fans to rotate at a much higher speed than the separator. This new design, the Dual Fan Separator (DFS) has been designed, prototyped and tested. This paper will outline the studies and analysis performed to develop the design configuration for testing. The studies included a configuration trade study, dynamic stability analysis of the rotating bodies and a performance analysis of included labyrinth seals. NASA is considereing a program to fly the UWMS aboard the ISS as a flight experiment. The goal of the design activity is to elevate the Technical Readiness Level (TRL) of the Dual Fan Separator and determine if the concept is ready to be included in flight experiment deliverable.

Stapleton, Tom; Converse, Dave; Broyan, James Lee, Jr.

2014-01-01

219

Negative heat capacity at phase-separation in macroscopic systems  

E-print Network

Systems with long-range as well with short-range interactions should necessarily have a convex entropy S(E) at proper phase transitions of first order, i.e. when a separation of phases occurs. Here the microcanonical heat capacity c(E)= -\\frac{(\\partial S/\\partial E)^2}{\\partial^2S/\\partial E^2} is negative. This should be observable even in macroscopic systems when energy fluctuations with the surrounding world can be sufficiently suppressed.

D. H. E. Gross

2005-08-19

220

Development of magnetic separation methods of analysis: magnetic field flow fractionation  

E-print Network

Tagging Of Bov1ne Serum Albumin By Nickel Ions And Magnetic FFF Ana lys1s Sam le Ni A lied Ma . Field Dro Retention Time 1. BSA 0 2. BSA 3. N1 + BSA -5. 0 X 10 M 4. Ni + BSA -5. 0 X 10 M 200 G 200 G 24. 0 min 24. 0 min 24. 0 m1n 25. 5 min... Bell Inc. , Model 640 Gaussmeter Detector ? Standard HPLC ultrav1olet detector (254 nm excitation wavelength) with 8 ul cell volume and 20 ul injection port volume BSA Concentrat1on - 1. 0 X 10 M in I and 2; 5 X 10 M in 3 and 4. 28 Table II lists...

Garcia-Ramirez, Jaime

2012-06-07

221

On a plasma sheath separating regions of oppositely directed magnetic field  

Microsoft Academic Search

Summary  An exact solution of the Vlasov equations is found which describes a layer of plasma confined between two regions of oppositely\\u000a directed magnetic field. The electrons and ions have Maxwellian distributions on the plane where the magnetic field vanishes.\\u000a In the coordinate system, in which the electron and ion drift velocities are equal in magnitude but opposite in direction,\\u000a the

E. G. Harris

1962-01-01

222

Exploring planetary magnetic environments using magnetically unclean spacecraft: a systems approach to VEX MAG data analysis  

NASA Astrophysics Data System (ADS)

In situ measurements of the magnetic field are vital to the study of many fundamental problems in planetary research. Therefore the magnetometer experiment is a key element of the payload of Venus Express. In addition to the interaction of the solar wind with Venus, these measurements are crucial for the study of atmospheric escape and detection of lightning. However, the methodology for the magnetic field measurements had to be different to the traditional approach, because Venus Express is not a magnetically clean spacecraft. A technique based on two-point simultaneous measurements of the magnetic field and systems identification software is used to separate the natural magnetic field from the spacecraft generated interference. In this paper an overview of the techniques developed to separate these two field types and the results achieved for 1 Hz Venus Express data are presented. Previous publications suggest that the resulting Venus Express cleaned data is of comparable quality to measurements made from onboard magnetically clean spacecraft (Zhang et al., 2008a, b; Slavin et al., 2009).

Pope, S. A.; Zhang, T. L.; Balikhin, M. A.; Delva, M.; Hvizdos, L.; Kudela, K.; Dimmock, A. P.

2011-04-01

223

Combined electrophoretic-separation and electrospray method and system  

DOEpatents

A system and method for analyzing molecular constituents of a composition sample includes: forming a solution of the sample, separating the solution by capillary zone electrophoresis into an eluent of constituents longitudinally separated according to their relative electrophoretic mobilities, electrospraying the eluent to form a charged spray in which the molecular constituents have a temporal distribution; and detecting or collecting the separated constituents in accordance with the temporal distribution in the spray. A first high-voltage (e.g., 5--100 kVDC) is applied to the solution. The spray is charged by applying a second high voltage (e.g., [+-]2--8 kVDC) between the eluent at the capillary exit and a cathode spaced in front of the exit. A complete electrical circuit is formed by a conductor which directly contacts the eluent at the capillary exit. 10 figs.

Smith, R.D.; Olivares, J.A.

1989-06-27

224

Combined electrophoretic-separation and electrospray method and system  

DOEpatents

A system and method for analyzing molecular constituents of a composition sample includes: forming a solution of the sample, separating the solution by capillary zone electrophoresis into an eluent of constituents longitudinally separated according to their relative electrophoretic mobilities, electrospraying the eluent to form a charged spray in which the molecular constituents have a temporal distribution; and detecting or collecting the separated constituents in accordance with the temporal distribution in the spray. A first high-voltage (e.g., 5-100 KVDC) is applied to the solution. The spray is charged by applying a second high voltage (e.g., .+-.2-8 KVDC) between the eluent at the capillary exit and a cathode spaced in front of the exit. A complete electrical circuit is formed by a conductor which directly contacts the eluent at the capillary exit.

Smith, Richard D. (Richland, WA); Olivares, Jose A. (Kennewick, WA)

1989-01-01

225

Rationale for two phase polymer system microgravity separation experiments  

NASA Technical Reports Server (NTRS)

The two-phase systems that result when aqueous solutions of dextran and poly(ethylene glycol) are mixed at concentrations above a few percent are discussed. They provide useful media for the partition and isolation of macromolecules and cell subpopulations. By manipulating their composition, separations based on a variety of molecular and surface properties are achieved, including membrane hydrophobic properties, cell surface charge, and membrane antigenicity. Work on the mechanism of cell partition shows there is a randomizing, nonthermal energy present which reduces separation resolution. This stochastic energy is probably associated with hydrodynamic interactions present during separation. Because such factors should be markedly reduced in microgravity, a series of shuttle experiments to indicate approaches to increasing the resolution of the procedure are planned.

Brooks, D. E.; Bamberger, S. B.; Harris, J. M.; Vanalstine, J.

1984-01-01

226

Reconstruction of magnetic source images using the Wiener filter and a multichannel magnetic imaging system.  

PubMed

A system for imaging magnetic surfaces using a magnetoresistive sensor array is developed. The experimental setup is composed of a linear array of 12 sensors uniformly spaced, with sensitivity of 150 pT*Hz(-1/2) at 1 Hz, and it is able to scan an area of (16 × 18) cm(2) from a separation of 0.8 cm of the sources with a resolution of 0.3 cm. Moreover, the point spread function of the multi-sensor system is also studied, in order to characterize its transference function and to improve the quality in the restoration of images. Furthermore, the images are generated by mapping the response of the sensors due to the presence of phantoms constructed of iron oxide, which are magnetized by a pulse of 80 mT. The magnetized phantoms are linearly scanned through the sensor array and the remanent magnetic field is acquired and displayed in gray levels using a PC. The images of the magnetic sources are reconstructed using two-dimensional generalized parametric Wiener filtering. Our results exhibit a very good capability to determine the spatial distribution of magnetic field sources, which produce magnetic fields of low intensity. PMID:25085156

Leyva-Cruz, J A; Ferreira, E S; Miltão, M S R; Andrade-Neto, A V; Alves, A S; Estrada, J C; Cano, M E

2014-07-01

227

Reconstruction of magnetic source images using the Wiener filter and a multichannel magnetic imaging system  

NASA Astrophysics Data System (ADS)

A system for imaging magnetic surfaces using a magnetoresistive sensor array is developed. The experimental setup is composed of a linear array of 12 sensors uniformly spaced, with sensitivity of 150 pT*Hz-1/2 at 1 Hz, and it is able to scan an area of (16 × 18) cm2 from a separation of 0.8 cm of the sources with a resolution of 0.3 cm. Moreover, the point spread function of the multi-sensor system is also studied, in order to characterize its transference function and to improve the quality in the restoration of images. Furthermore, the images are generated by mapping the response of the sensors due to the presence of phantoms constructed of iron oxide, which are magnetized by a pulse of 80 mT. The magnetized phantoms are linearly scanned through the sensor array and the remanent magnetic field is acquired and displayed in gray levels using a PC. The images of the magnetic sources are reconstructed using two-dimensional generalized parametric Wiener filtering. Our results exhibit a very good capability to determine the spatial distribution of magnetic field sources, which produce magnetic fields of low intensity.

Leyva-Cruz, J. A.; Ferreira, E. S.; Miltão, M. S. R.; Andrade-Neto, A. V.; Alves, A. S.; Estrada, J. C.; Cano, M. E.

2014-07-01

228

Magnetic induction systems to harvest energy from mechanical vibrations  

E-print Network

This thesis documents the design process for magnetic induction systems to harvest energy from mechanical vibrations. Two styles of magnetic induction systems - magnet-through-coil and magnet-across-coils - were analyzed. ...

Jonnalagadda, Aparna S

2007-01-01

229

Cooling system for superconducting magnet  

DOEpatents

A cooling system is configured to control the flow of a refrigerant by controlling the rate at which the refrigerant is heated, thereby providing an efficient and reliable approach to cooling a load (e.g., magnets, rotors). The cooling system includes a conduit circuit connected to the load and within which a refrigerant circulates; a heat exchanger, connected within the conduit circuit and disposed remotely from the load; a first and a second reservoir, each connected within the conduit, each holding at least a portion of the refrigerant; a heater configured to independently heat the first and second reservoirs. In a first mode, the heater heats the first reservoir, thereby causing the refrigerant to flow from the first reservoir through the load and heat exchanger, via the conduit circuit and into the second reservoir. In a second mode, the heater heats the second reservoir to cause the refrigerant to flow from the second reservoir through the load and heat exchanger via the conduit circuit and into the first reservoir.

Gamble, Bruce B. (Wellesley, MA); Sidi-Yekhlef, Ahmed (Framingham, MA)

1998-01-01

230

Test and evaluation of a 50-gallon-per-minute oil\\/water separator (Separation and Recovery Systems, Inc. )  

Microsoft Academic Search

This report covers the test and evaluation of a Separation and Recovery Systems, Inc. (SRS), 50-gallon-per-minute (gpm) oil\\/water separation system to determine its suitability as a shipboard oil-pollution control device. This report concludes that: the SRS, 50-GPM oil\\/water separator should be considered a candidate for further detailed testing to confirm its suitability as a further detailed testing to confirm its

1972-01-01

231

Polymeric membrane systems of potential use for battery separators  

NASA Technical Reports Server (NTRS)

Two membrane systems were investigated that may have potential use as alkaline battery separators. One system comprises two miscible polymers: a support polymer (e.g., polyvinyl formal) and an ion conductor such as polyacrylic acid. The other system involves a film composed of two immiscible polymers: a conducting polymer (e.g., calcium polyacrylate) suspended in an inert polymer support matrix, polyphenylene oxide. Resistivities in 45-percent potassium hydroxide and qualitative mechanical properties are presented for films comprising various proportions of conducting and support polymers. In terms of these parameters, the results are encouraging for optimum ratios of conducting to support polymers.

Philipp, W. H.

1977-01-01

232

Near-surface epigenetic magnetic indicators of buried hydrocarbons and separation of spurious signals  

SciTech Connect

Significant geochemical alteration zones occurring over buried hydrocarbon deposits can be recognized and mapped by geophysical methods. The authors believe near-surface secondary magnetic minerals formed as a result of seeping hydrocarbons and associated compounds interacting with constituents of the overlying rocks. A new method is described to identify anomalous magnetic signatures associated with this mineralization, and to differentiate that signal from cultural interference and other surface shallow, and intermediate-depth geologic sources. Using low-altitude, high-sensitivity aeromagnetic data, the separation involves detailed spectral analysis, subsequent band-pass filtering, and analytic signal transformation of the filtered data. Depicted in contour form, the analytic signal minimizes spatial aliasing and allows us to map the areal distribution of subtle, near-surface anomalies related to probable epigenetic magnetic mineralization. This method is illustrated using data from the Arctic National Wildlife Refuge and Cook Inlet, Alaska, and from offshore Texas, where high-resolution seismic data support the aeromagnetic interpretation and suggest important structural controls. Correlations of published detailed gravimeter and low-altitude aeromagnetic data at the Cement oil field, Oklahoma, were coupled with interactive modeling studies. Except for the obvious extreme high wave-number spikes, cultural contamination cannot be responsible for the high wave-number signal there, and the epigenetic magnetic mineralization may be more extensive vertically than originally suggested.

Donovan, T.J.; O'Brien, D.P.; Bryan, J.G.; Shepherd, M.A.

1986-05-01

233

Desulphurization of lignites by slow, fast, and flash pyrolysis and high intensity dry magnetic separation  

SciTech Connect

Slow, fast and flash pyrolysis followed by high intensity dry magnetic (HIDM) separation experiments were conducted to obtain improved solid fuels. Pyrolysis experiments were performed in three different apparatus, and important parameters of processes, temperature, particle size, residence time and heating rate were studied to determine the optimum conditions. Desulphurization of lignites by flash pyrolysis is more successful than slow and fast pyrolysis. At optimum conditions of pyrolysis, up to 58.15, 60.24, and 62.31% sulphur reductions were obtained in slow, fast and flash pyrolysis, respectively. Char, obtained from the pyrolysis experiments, was further cleaned by a Permroll HIDM separator. Sulphur reduction enhanced up to 82.68, 84.40, and 86.55% in the char of slow, fast and flash pyrolysis, respectively.

Koca, H.; Kockar, O.M.; Koca, S. [Anadolu University, Eskisehir (Turkey). Porsuk Technical College

2007-07-01

234

High gradient magnetic separation of iron oxide minerals from soil clays  

E-print Network

. The titanium oxide minerals, anatase and rutile, were identified by peaks at 3. 52A and 3. 25A respectively (Hutton, 1977). In many D 0 cases, the 3. 52A anatase peak could not be resolved from the 3. 57A kaolinite peak until the kaolinite peak... was destroyed by heating at 550'C. The 3. 52A and 3. 25A peaks are the strongest peaks for anatase and rutile and are the only ones normally observed in routine x-ray diffraction analysis. 25 RESULTS AND DISCUSSION Effectiveness of Magnetic Separation...

Schulze, Darrell Gene

2012-06-07

235

Mixing and Phase Separation in Liquid Crystal/matrix Systems  

NASA Astrophysics Data System (ADS)

We review mixing and phase separation (demixing) in mixtures of low molecular weight liquid crystals (LCs) and organic matrices, with emphasis on aspects relevant to the formation of polymer-dispersed liquid crystal films. These films, which contain a myriad of micron-sized LC droplets, are of interest because of their electro-optic properties. Film formation is simple: A liquid crystal and a liquid polymer precursor are initially mixed to form a single phase. Subsequently the polymer is hardened, and LC microdroplets phase-separate from the matrix. Although matrix hardening can be achieved in several ways, this review focuses on curing, during which cross-linking reactions lead to an increased matrix molecular weight. Topics discussed include: phase behavior of the binary system before, during, and after cure and LC/matrix solubilities. The Flory-Huggins model for phase separation (as modified by several workers) has provided a theoretical basis for the studies. Principal experimental tools have been calorimetry and light scattering. Uncured LC/matrix binaries possess phase diagrams with an upper critical solution temperature. Such systems, when heated through the mixing temperature, exhibit a decrease in specific heat, the (negative) excess specific heat of mixing, °Cmix. A plot of °Cmix vs. LC concentration exhibits a minimum, from which we can estimate LC and uncured-matrix solubilities. Matrix cure plays a major role in the phase separation process: In partially-cured samples, °Cmix transitions persist until cure is nearly complete, at which time a fraction of the LC is permanently phase-separated, with the rest remaining dissolved in the matrix. The kinetics of phase separation can be determined by calorimetry or light scattering. Cure rates have been shown to control LC microdroplet size, with fast cures leading to small droplets. Calorimetry of the fully cured system also allows us to determine the solubility of liquid crystal in the polymer matrix, as well as the fraction of phase-separated LC. An approximation based on the lever rule and the Flory-Huggins spinodal curve provides an upper bound for the solubilities and also describes their temperature dependence.

Smith, George W.

236

Attractive and repulsive magnetic suspension systems overview  

NASA Technical Reports Server (NTRS)

Magnetic suspension systems can be used in a wide variety of applications. The decision of whether to use an attractive or repulsive suspension system for a particular application is a fundamental one which must be made during the design process. As an aid to the designer, we compare and contrast attractive and repulsive magnetic suspension systems and indicate whether and under what conditions one or the other system is preferred.

Cope, David B.; Fontana, Richard R.

1992-01-01

237

Magnetic-field-dosimetry system  

DOEpatents

A device is provided for measuring the magnetic field dose and peak field exposure. The device includes three Hall-effect sensors all perpendicular to each other, sensing the three dimensional magnetic field and associated electronics for data storage, calculating, retrieving and display.

Lemon, D.K.; Skorpik, J.R.; Eick, J.L.

1981-01-21

238

Magnetically suspended flywheel system study  

Microsoft Academic Search

A program to study the application of a graphite\\/epoxy, magnetically suspended, pierced disk flywheel for the combined function of spacecraft attitude control and energy storage (ACES) is described. Past achievements of the program include design and analysis computer codes for the flywheel rotor, a magnetically suspended flywheel model, and graphite\\/epoxy rotor rings that were successfully prestressed via interference assembly. All

J. A. Kirk; D. K. Anand; H. E. Evans; G. E. Rodriguez

1984-01-01

239

Dual Fan Separator within the Universal Waste Management System  

NASA Technical Reports Server (NTRS)

Since NASA's new spacecraft in development for both LEO and Deep Space capability have considerable crew volume reduction in comparison to the Space Shuttle, the need became apparent for a smaller commode. In response the Universal Waste Management System (UWMS) was designed, resulting in an 80% volume reduction from the last US commode, while enhancing performance. The ISS WMS and previous shuttle commodes have a fan supplying air flow to capture feces and a separator to capture urine and separate air from the captured air/urine mixture. The UWMS combined both rotating equipment components into a single unit, referred to at the Dual Fan Separator (DFS). The combination of these components resulted in considerable packaging efficiency and weight reduction, removing inter-component plumbing, individual mounting configurations and required only a single motor and motor controller, in some of the intended UWMS platform applications the urine is pumped to the ISS Urine Processor Assembly (UPA) system. It requires the DFS to include less than 2.00% air inclusion, by volume, in the delivered urine. The rotational speed needs to be kept as low as possible in centrifugal urine separators to reduce air inclusion in the pumped fluid, while fans depend on rotational speed to develop delivered head. To satisfy these conflicting requirements, a gear reducer was included, allowing the fans to rotate at a much higher speed than the separator. This paper outlines the studies and analysis performed to develop the DFS configuration. The studies included a configuration trade study, dynamic stability analysis of the rotating bodies and a performance analysis of included labyrinth seals. NASA is considering a program to fly the UWMS aboard the ISS as a flight experiment. The goal of this activity is to advance the Technical Readiness Level (TRL) of the DFS and determine if the concept is ready to be included as part of the flight experiment deliverable.

Stapleton, Tom; Converse, Dave; Broyan, James Lee, Jr.

2014-01-01

240

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

DOEpatents

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.

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

1999-01-01

241

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

DOEpatents

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. 1 fig.

Judkins, R.R.; Burchell, T.D.

1999-07-20

242

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

PubMed Central

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 that non-specific binding of magnetic nanoparticles can impart a magnetization to cells such that these cells can be retained in a separation column and thus negatively impact the purity of the final product and the recovery of the desired cells. Through experimental data and theoretical arguments, we demonstrate that the number of MACS magnetic particles needed to impart a magnetization that is sufficient to causes non-targeted cells to be retained in the column to be on the order of 500 to 1,000 nanoparticles. This number of non-specifically bound particles was demonstrated experimentally with an instrument, cell tracking velocimeter, CTV, and it is demonstrated that the sensitivity of the CTV instrument for Fe atoms contained in magnetic nanoparticles on the order of 1 × 10?15 g/mL of Fe. PMID:20014141

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

2012-01-01

243

Separation of fast and slow variables for a linear system by the method of multiple time scales  

Microsoft Academic Search

A matrix method, introduced by Geigenmuller, Titulaer and Felderhof, for separating fast and slow motions of a system of first order linear differential equations is shown to arise in a natural way from a multiple time scales expansion. The general method is then used to derive the Smoluchowski equation (and its initial data) for Brownian motion in a strong magnetic

David Wycoff; N. L. Balazs

1987-01-01

244

Active tensor magnetic gradiometer system final report for Project MM–1514  

USGS Publications Warehouse

An interactive computer simulation program, based on physical models of system sensors, platform geometry, Earth environment, and spheroidal magnetically-permeable targets, was developed to generate synthetic magnetic field data from a conceptual tensor magnetic gradiometer system equipped with an active primary field generator. The system sensors emulate the prototype tensor magnetic gradiometer system (TMGS) developed under a separate contract for unexploded ordnance (UXO) detection and classification. Time-series data from different simulation scenarios were analyzed to recover physical dimensions of the target source. Helbig-Euler simulations were run with rectangular and rod-like source bodies to determine whether such a system could separate the induced component of the magnetization from the remanent component for each target. This report concludes with an engineering assessment of a practical system design.

Smith, David V.; Phillips, Jeffrey D.; Hutton, S. Raymond

2014-01-01

245

Magnetic network model including loss separation and Preisach principles for the evaluation of core losses in devices  

NASA Astrophysics Data System (ADS)

In this paper, a method is developed to calculate the core loss in a switched reluctance machine. The magnetic circuit of the motor is described as a magnetic network. The electromagnetic behavior of each magnetic network element takes into account the iron loss using the Preisach model and the principle of loss separation. Using the numerical routines, the local core loss in the different motor sections is calculated. The global core loss is compared with the experimentally determined core loss.

Dupré, Luc; Sergeant, Peter; Vandenbossche, Lode

2005-05-01

246

Study on control method of running velocity for the permanent magnet-HTSC hybrid magnetically levitated conveyance system  

NASA Astrophysics Data System (ADS)

We have developed the magnetically levitated carrying system. In this system, pinning force of high temperature bulk super conductor (HTSC) is used for the levitation and guidance. Four HTSCs are installed on the carrier. The magnetic rail is set on the ground, and flux from the magnetic rail is pinned by HTSCs. To increase levitation force, repulsive force of the permanent magnet is used. The hybrid levitation system is composed. The permanent magnet is installed under the load stage of the carrier. Repulsive force by the permanent magnet between the load stage on the carrier and the magnetic rail on the ground is used to support the load weight. Levitation and guidance one by pinning effect of the YBaCuO HTSC in the carrier is used to levitate the carrier body. The load stage is separated from the carrier flame and can move freely for vertical direction levitation. For the propulsion system, electromagnet is installed on the surface of the magnetic rail. In this paper, control method of running velocity of the carrier is studied. Propulsion force is given as follows; Air core copper coils are installed on the magnetic rail. Interaction between current of these coils and permanent magnets on the carrier generates propulsion force. Running velocity is controlled by current of the propulsion coils. It is also changed by position of the carrier and the load weight. From the results, stability of the propulsion system is given, and propulsion characteristics are improved.

Nishio, R.; Ikeda, M.; Sasaki, R.; Ohashi, S.

2011-11-01

247

Planetary magnetism in the outer solar system.  

NASA Technical Reports Server (NTRS)

A brief review of the salient considerations which apply to the existence of magnetic fields in connection with planetary and subplanetary objects in the outer solar system is given. Consideration is given to internal dynamo fields, fields which might originate from interaction with the solar wind or magnetospheres (externally driven dynamos) and lastly fossil magnetic fields such as have been discovered on the moon. Where possible, connection is made between magnetism, means of detection, and internal body properties.

Sonett, C. P.

1973-01-01

248

A New Unified Scheme for Controlled Power System Separation Using Synchronized Phasor Measurements  

Microsoft Academic Search

Controlled power system separation, which separates the transmission system into islands in a controlled manner, is considered the final resort against a blackout under severe disturbances, e.g., cascading events. Three critical problems of controlled separation are where and when to separate and what to do after separation, which are rarely studied together. They are addressedinthispaperbyaproposedunifiedcontrolledseparation scheme based on synchrophasors. The

Kai Sun; Kyeon Hur; Pei Zhang

2011-01-01

249

Synthesis of magnetic ion-imprinted composites and selective separation and preconcentration of U(VI).  

PubMed

The U(VI) magnetic ion-imprinted composite (MIIC) with a uniform core-shell structure for the selective separation and preconcentration of U(VI) was prepared by copolymerization of a ternary complex of uranyl ions with 4-vinylpyridine (4-VP) and acrylamide in the presence of 2,2'-azobisisobutyronitrile. The sorption of U(VI) on the MIIC from aqueous solution was evaluated. The maximum sorption capacity of MIIC for U(VI) was 354.85 mg g(-1), which was much higher than that of the magnetic nonimprinted composite. The MIIC could be recovered by desorbing the U(VI)-loaded MIIC with 0.5 mol L(-1) HNO3, and the surface morphology of MIIC after five consecutive sorption/desorption cycles was significantly damaged. The competitive sorption experiments showed that the MIIC had a desirable selectivity for U(VI) over a range of competing metal ions. The MIIC may be a promising sorbent material for the selective separation and preconcentration of U(VI). PMID:24667936

Liu, Mancheng; Chen, Changlun; Wen, Tao; Wang, Xiangke

2014-05-21

250

Synthesis of teicoplanin-modified hybrid magnetic mesoporous silica nanoparticles and their application in chiral separation of racemic compounds.  

PubMed

Teicoplanin-conjugated mesoporous silica magnetic nanoparticles (TE-MSMNPs) were fabricated as novel chiral magnetic nano-selectors. Successful preparation of the functional magnetic mesoporous materials was achieved by grafting teicoplanin on N-(2-aminoethyl)-3-aminopropyltrimethoxysilane-modified mesoporous silica Fe3O4 magnetic nanoparticles (AEAPTMS-MSMNPs), and this was confirmed by various characterization techniques. The synthesized magnetic nanoparticles were regularly spherical and uniformly mesoporous with an average diameter of around 600 nm and a mean pore size of about 3.9 nm, respectively. These versatile magnetic nanoparticles were effective in a direct chiral separation of five racemic compounds in phosphate buffer. Much stronger interactions were observed with the (+)-enantiomers than with the (-)-enantiomers. After washing with water and ethanol by sonication, TE-MSMNPs could be reused at least three times with little efficiency loss. The functional magnetic mesoporous nanoparticles were easily separated from the racemic solutions using an external magnetic field. These magnetic nano-materials are suitable for enantiomer separations. PMID:23541694

Wu, Jingwei; Su, Ping; Huang, Jun; Wang, Siming; Yang, Yi

2013-06-01

251

MICE Spectrometer Magnet System Progress  

SciTech Connect

The first magnets for the muon ionization cooling experimentwill be the tracker solenoids that form the ends of the MICE coolingchannel. The primary purpose of the tracker solenoids is to provide auniform 4 T field (to better than +-0.3 percent over a volume that is 1meter long and 0.3 meters in diameter) spectrometer magnet field for thescintillating fiber detectors that are used to analyze the muons in thechannel before and after ionization cooling. A secondary purpose for thetracker magnet is the matching of the muon beam between the rest of theMICE cooling channel and the uniform field spectrometer magnet. Thetracker solenoid is powered by three 300 amp power supplies. Additionaltuning of the spectrometer is provided by a pair of 50 amp power suppliesacross the spectrometer magnet end coils. The tracker magnet will becooled using a pair of 4 K pulse tube coolers that each provide 1.5 W ofcooling at 4.2 K. Final design and construction of the tracker solenoidsbegan during the summer of 2006. This report describes the progress madeon the construction of the tracker solenoids.

Green, Michael A.; Virostek, Steve P.

2007-08-27

252

Separations technologies supporting the development of a deployable ATW system  

SciTech Connect

A program has been initiated for the purpose of developing the chemical separations technologies necessary to support a large Accelerator Transmutation of Waste (ATW) system capable of dealing with the projected inventory of spent fuel from the commercial nuclear power stations in the United States. The first several years of the program will be directed toward an elucidation of related technical issues and to the establishment, by means of comprehensive trade studies, of an optimum configuration of the elements of the chemical processing infrastructure required for support of the total ATW system. By adopting this sort of disciplined systems engineering approach, it is expected that development and demonstration costs can be minimized and that it will be possible to deploy an ATW system that is an environmentally sound and economically viable venture.

Laidler, J. J.

2000-01-07

253

Label-free cell separation and sorting in microfluidic systems  

PubMed Central

Cell separation and sorting are essential steps in cell biology research and in many diagnostic and therapeutic methods. Recently, there has been interest in methods which avoid the use of biochemical labels; numerous intrinsic biomarkers have been explored to identify cells including size, electrical polarizability, and hydrodynamic properties. This review highlights microfluidic techniques used for label-free discrimination and fractionation of cell populations. Microfluidic systems have been adopted to precisely handle single cells and interface with other tools for biochemical analysis. We analyzed many of these techniques, detailing their mode of separation, while concentrating on recent developments and evaluating their prospects for application. Furthermore, this was done from a perspective where inertial effects are considered important and general performance metrics were proposed which would ease comparison of reported technologies. Lastly, we assess the current state of these technologies and suggest directions which may make them more accessible. Figure A wide range of microfluidic technologies have been developed to separate and sort cells by taking advantage of differences in their intrinsic biophysical properties PMID:20419490

Gossett, Daniel R.; Weaver, Westbrook M.; Mach, Albert J.; Hur, Soojung Claire; Tse, Henry Tat Kwong; Lee, Wonhee; Amini, Hamed

2010-01-01

254

Chemical separations schemes for partitioning and transmutation systems.  

SciTech Connect

In the initial phase of the U.S. Accelerator Transmutation of Waste (ATW) program, a single-tier system was foreseen in which the transuranics and long-lived fission products (specifically, {sup 99}Tc and {sup 129}I) recovered from spent LWR oxide fuel would be sent directly to an accelerator-driven transmuter reactor [1]. Because the quantity of fuel to be processed annually was so large (almost 1,500 tons per year), an aqueous solvent extraction process was chosen for LWR fuel processing. Without the need to separate transuranics from one another for feed to the transmuter, it became appropriate to develop an advanced aqueous separations method that became known as UREX. The UREX process employs an added reagent (acetohydroxamic acid) that suppresses the extraction of plutonium and promotes the extraction of technetium together with uranium. Technetium can then be efficiently removed from the uranium; the recovered uranium, being highly decontaminated, can be disposed of as a low-level waste or stored in an unshielded facility for future use. Plutonium and the other transuranic elements, plus the remaining fission products, are directed to the liquid waste stream. This stream is calcined, converting the transuranics and fission products to their oxides. The resulting oxide powder, now representing only about four percent of the original mass of the spent fuel, is reduced to metallic form by means of a pyrometallurgical process. Subsequently, the transuranics are separated from the fission products in another pyro-metallurgical step involving molten salt electrorefining.

Laidler, J.

2002-05-02

255

Control of Systems With Slow Actuators Using Time Scale Separation  

NASA Technical Reports Server (NTRS)

This paper addresses the problem of controlling a nonlinear plant with a slow actuator using singular perturbation method. For the known plant-actuator cascaded system the proposed scheme achieves tracking of a given reference model with considerably less control demand than would otherwise result when using conventional design techniques. This is the consequence of excluding the small parameter from the actuator dynamics via time scale separation. The resulting tracking error is within the order of this small parameter. For the unknown system the adaptive counterpart is developed based on the prediction model, which is driven towards the reference model by the control design. It is proven that the prediction model tracks the reference model with an error proportional to the small parameter, while the prediction error converges to zero. The resulting closed-loop system with all prediction models and adaptive laws remains stable. The benefits of the approach are demonstrated in simulation studies and compared to conventional control approaches.

Stepanyan, Vehram; Nguyen, Nhan

2009-01-01

256

Multiparameter magnetic inspection system with magnetic field control and plural magnetic transducers  

DOEpatents

A multiparameter magnetic inspection system for providing an efficient and economical way to derive a plurality of independent measurements regarding magnetic properties of the magnetic material under investigation. The plurality of transducers for a plurality of different types of measurements operatively connected to the specimen. The transducers are in turn connected to analytical circuits for converting transducer signals to meaningful measurement signals of the magnetic properties of the specimen. The measurement signals are processed and can be simultaneously communicated to a control component. The measurement signals can also be selectively plotted against one another. The control component operates the functioning of the analytical circuits and operates and controls components to impose magnetic fields of desired characteristics upon the specimen. The system therefore allows contemporaneous or simultaneous derivation of the plurality of different independent magnetic properties of the material which can then be processed to derive characteristics of the material.

Jiles, David C. (Ames, IA)

1991-04-16

257

Multiparameter magnetic inspection system with magnetic field control and plural magnetic transducers  

DOEpatents

A multiparameter magnetic inspection system is disclosed for providing an efficient and economical way to derive a plurality of independent measurements regarding magnetic properties of the magnetic material under investigation. The plurality of transducers for a plurality of different types of measurements operatively connected to the specimen. The transducers are in turn connected to analytical circuits for converting transducer signals to meaningful measurement signals of the magnetic properties of the specimen. The measurement signals are processed and can be simultaneously communicated to a control component. The measurement signals can also be selectively plotted against one another. The control component operates the functioning of the analytical circuits and operates and controls components to impose magnetic fields of desired characteristics upon the specimen. The system therefore allows contemporaneous or simultaneous derivation of the plurality of different independent magnetic properties of the material which can then be processed to derive characteristics of the material. 1 figure.

Jiles, D.C.

1991-04-16

258

Magnetic suspension and balance system advanced study  

NASA Technical Reports Server (NTRS)

An improved compact design for a superconducting magnetic suspension and balance system for an 8 ft. x 8 ft. transonic wind tunnel is developed. The original design of an MSBS in NASA Cr-3802 utilized 14 external superconductive coils and a superconductive solenoid in the airplane test model suspended in a wind tunnel. The improvements are in the following areas: test model solenoid options, dynamic force limits on the model, magnet cooling options, structure and cryogenic designs, power supply specifications, and cost and performance evaluations. The improvements are: MSBS cost reduction of 28%, weight; reduction of 43%, magnet system ampere-meter reduction of 38%, helium liquifier capacity reduction by 33%, magnet system stored energy reduction by 55%, AC loss to liquid helium reduced by 76%, system power supply reduced by 68%, test coil pole strength increased by 19%, wing magnetization increased by 40%, and control frequency limit increased by 200% from 10 Hz to 30 Hz. The improvements are due to: magnetic holmium coil forms in the test model, better rare earth permanent magnets in the wings, fiberglass-epoxy structure replacing stainless steel, better coil configuration, and new saddle roll coil design.

Boom, R. W.; Eyssa, Y. M.; Mcintosh, G. E.; Abdelsalam, M. K.

1985-01-01

259

Magnetic Levitation System The following figure shows the cross section of a magnetic levitation (MAGLEV) train.  

E-print Network

Magnetic Levitation System The following figure shows the cross section of a magnetic levitation in matched pairs. The magnetic attraction of the vertically paired magnets balances the force of gravity and levitates the vehicle above the guideway. d h z Train Track Magnets Fixed Reference Line Magnets

Hagan, Martin

260

A NOVEL CO{sub 2} SEPARATION SYSTEM  

SciTech Connect

Because of concern over global climate change, new systems are needed that produce electricity from fossil fuels and emit less CO{sub 2}. The fundamental problem with current systems which recover and concentrate CO{sub 2} from flue gases is the need to separate dilute CO{sub 2} and pressurize it to roughly 35 atm for storage or sequestration. This is an energy intensive process that can reduce plant efficiency by 9-37% and double the cost of electricity. There are two fundamental reasons for the current high costs of power consumption, CO{sub 2} removal, and concentration systems: (1) most disposal, storage and sequestering systems require high pressure CO{sub 2} (at roughly 35 atm). Thus, assuming 90% removal of the CO{sub 2} from a typical atmospheric pressure flue gas that contains 10% CO{sub 2}, the CO{sub 2} is essentially being compressed from 0.01 atm to 35 atm (a pressure ratio of 3,500). This is a very energy intensive process. (2) The absorption-based (amine) separation processes that are used to remove the CO{sub 2} from the flue gas and compress it to 1 atm consume approximately 10 times as much energy as the theoretical work of compression because they are heat driven cycles working over a very low temperature difference. Thus, to avoid the problems of current systems, we need a power cycle in which the CO{sub 2} produced by the oxidation of the fuel is not diluted with a large excess of nitrogen, a power cycle which would allow us to eliminate the very inefficient thermally driven absorption/desorption step. In addition, we would want the CO{sub 2} to be naturally available at high pressure (approximately 3 to 6 atmospheres), which would allow us to greatly reduce the compression ratio between generation and storage (from roughly 3,500 to approximately 8).

Robert J. Copeland

2000-03-01

261

A NOVEL CO{sub 2} SEPARATION SYSTEM  

SciTech Connect

Because of concern over global climate change, new systems are needed that produce electricity from fossil fuels and emit less CO{sub 2}. The fundamental problem with current systems which recover and concentrate CO{sub 2} from flue gases is the need to separate dilute CO{sub 2} and pressurize it to roughly 35 atm for storage or sequestration. This is an energy intensive process that can reduce plant efficiency by 9-37% and double the cost of electricity. There are two fundamental reasons for the current high costs of power consumption, CO{sub 2} removal, and concentration systems: (1) most disposal, storage and sequestering systems require high pressure CO{sub 2} (at roughly 35 atm). Thus, assuming 90% removal of the CO{sub 2} from a typical atmospheric pressure flue gas that contains 10% CO{sub 2}, the CO{sub 2} is essentially being compressed from 0.01 atm to 35 atm (a pressure ratio of 3,500). This is a very energy intensive process. (2) The absorption-based (amine) separation processes that are used to remove the CO{sub 2} from the flue gas and compress it to 1 atm consume approximately 10 times as much energy as the theoretical work of compression because they are heat driven cycles working over a very low temperature difference. Thus, to avoid the problems of current systems, we need a power cycle in which the CO{sub 2} produced by the oxidation of the fuel is not diluted with a large excess of nitrogen, a power cycle which would allow us to eliminate the very inefficient thermally driven absorption/desorption step. In addition, we would want the CO{sub 2} to be naturally available at high pressure (approximately 3 to 6 atmospheres), which would allow us to greatly reduce the compression ratio between generation and storage (from roughly 3,500 to approximately 8).

Robert J. Copeland

2000-08-01

262

A NOVEL CO{sub 2} SEPARATION SYSTEM  

SciTech Connect

Because of concern over global climate change, new systems are needed that produce electricity from fossil fuels and emit less CO{sub 2}. The fundamental problem with current systems which recover and concentrate CO{sub 2} from flue gases is the need to separate dilute CO{sub 2} and pressurize it to roughly 35 atm for storage or sequestration. This is an energy intensive process that can reduce plant efficiency by 9-37% and double the cost of electricity. There are two fundamental reasons for the current high costs of power consumption, CO{sub 2} removal, and concentration systems: (1) most disposal, storage and sequestering systems require high pressure CO{sub 2} (at roughly 35 atm). Thus, assuming 90% removal of the CO{sub 2} from a typical atmospheric pressure flue gas that contains 10% CO{sub 2}, the CO{sub 2} is essentially being compressed from 0.01 atm to 35 atm (a pressure ratio of 3,500). This is a very energy intensive process. (2) The absorption-based (amine) separation processes that are used to remove the CO{sub 2} from the flue gas and compress it to 1 atm consume approximately 10 times as much energy as the theoretical work of compression because they are heat driven cycles working over a very low temperature difference. Thus, to avoid the problems of current systems, we need a power cycle in which the CO{sub 2} produced by the oxidation of the fuel is not diluted with a large excess of nitrogen, a power cycle which would allow us to eliminate the very inefficient thermally driven absorption/desorption step. In addition, we would want the CO{sub 2} to be naturally available at high pressure (approximately 3 to 6 atmospheres), which would allow us to greatly reduce the compression ratio between generation and storage (from roughly 3,500 to approximately 8).

Robert J. Copeland

2000-05-01

263

Statistical Treatment of Earth Observing System Pyroshock Separation Test Data  

NASA Technical Reports Server (NTRS)

The Earth Observing System (EOS) AM-1 spacecraft for NASA's Mission to Planet Earth is scheduled to be launched on an Atlas IIAS vehicle in June of 1998. One concern is that the instruments on the EOS spacecraft are sensitive to the shock-induced vibration produced when the spacecraft separates from the launch vehicle. By employing unique statistical analysis to the available ground test shock data, the NASA Lewis Research Center found that shock-induced vibrations would not be as great as the previously specified levels of Lockheed Martin. The EOS pyroshock separation testing, which was completed in 1997, produced a large quantity of accelerometer data to characterize the shock response levels at the launch vehicle/spacecraft interface. Thirteen pyroshock separation firings of the EOS and payload adapter configuration yielded 78 total measurements at the interface. The multiple firings were necessary to qualify the newly developed Lockheed Martin six-hardpoint separation system. Because of the unusually large amount of data acquired, Lewis developed a statistical methodology to predict the maximum expected shock levels at the interface between the EOS spacecraft and the launch vehicle. Then, this methodology, which is based on six shear plate accelerometer measurements per test firing at the spacecraft/launch vehicle interface, was used to determine the shock endurance specification for EOS. Each pyroshock separation test of the EOS spacecraft simulator produced its own set of interface accelerometer data. Probability distributions, histograms, the median, and higher order moments (skew and kurtosis) were analyzed. The data were found to be lognormally distributed, which is consistent with NASA pyroshock standards. Each set of lognormally transformed test data produced was analyzed to determine if the data should be combined statistically. Statistical testing of the data's standard deviations and means (F and t testing, respectively) determined if data sets were significantly different at a 95-percent confidence level. If two data sets were found to be significantly different, these families of data were not combined for statistical purposes. This methodology produced three separate statistical data families of shear plate data. For each population, a P99.1/50 (probability/confidence) per-separation-nut firing level was calculated. By using the binomial distribution, Lewis researchers determined that this pernut firing level was equivalent to a P95/50 per-flight confidence level. The overall envelope of the per-flight P95/50 levels led to Lewis' recommended EOS interface shock endurance specification. A similar methodology was used to develop Lewis' recommended EOS mission assurance levels. The available test data for the EOS mission are significantly larger than for a normal mission, thus increasing the confidence level in the calculated expected shock environment. Lewis significantly affected the EOS mission by properly employing statistical analysis to the data. This analysis prevented a costly requalification of the spacecraft's instruments, which otherwise would have been exposed to significantly higher test levels.

McNelis, Anne M.; Hughes, William O.

1998-01-01

264

Polymerase chain reaction system using magnetic beads for analyzing a sample that includes nucleic acid  

DOEpatents

A polymerase chain reaction system for analyzing a sample containing nucleic acid includes providing magnetic beads; providing a flow channel having a polymerase chain reaction chamber, a pre polymerase chain reaction magnet position adjacent the polymerase chain reaction chamber, and a post pre polymerase magnet position adjacent the polymerase chain reaction chamber. The nucleic acid is bound to the magnetic beads. The magnetic beads with the nucleic acid flow to the pre polymerase chain reaction magnet position in the flow channel. The magnetic beads and the nucleic acid are washed with ethanol. The nucleic acid in the polymerase chain reaction chamber is amplified. The magnetic beads and the nucleic acid are separated into a waste stream containing the magnetic beads and a post polymerase chain reaction mix containing the nucleic acid. The reaction mix containing the nucleic acid flows to an analysis unit in the channel for analysis.

Nasarabadi, Shanavaz (Livermore, CA)

2011-01-11

265

Digital intelligent magnetic recording system DIMARS as the automated workstation at magnetic observatory  

NASA Astrophysics Data System (ADS)

The main concept of the Digital Intelligent Magnetic Recording System (DIMARS) for the registration of the Earth's magnetic field variations is the following: with the help of an embedded microprocessor it provides the necessary automated functions which provide a maximum available information for the annual report of a magnetic observatory. In this way the problem of compactness of the storage unit (5.25 inch floppy disk) with IBM PC XT/AT (or clone) has been solved. The functional block diagram of DIMARS is shown. The system permits the use of PC separately for the floppy processing and transmitting the files into PC via telephone link without changing a diskette. A standard matrix printer of PC can be used for recording of standard magnetogram with the 20 mm/h speed (in graphic mode). It is possible to attach a digital compact cassette magnetic recorder too. Quartz variometers with analog electric output are used in the system, but it is also possible to attach any other variometers, e.g., fluxgate sensors, etc. to the system.

Papitashvili, N. E.; Papitashvili, V. O.; Hegymegi, L.; Kormendi, A.; Lomniczi, T.

1990-02-01

266

Directional locking in deterministic lateral-displacement microfluidic separation systems  

NASA Astrophysics Data System (ADS)

We analyze the trajectory of suspended spherical particles moving through a square array of obstacles, in the deterministic limit and at zero Reynolds number. We show that in the dilute approximation of widely separated obstacles, the average motion of the particles is equivalent to the trajectory followed by a point particle moving through an array of obstacles with an effective radius. The effective radius accounts for the hydrodynamic as well as short-range repulsive nonhydrodynamic interactions between the suspended particles and the obstacles, and is equal to the critical offset at which particle trajectories become irreversible. Using this equivalent system we demonstrate the presence of directional locking in the trajectory of the particles and derive an inequality that accurately describes the "devil's staircase" type of structure observed in the migration angle as a function of the forcing direction. We use these results to determine the optimum resolution in the fractionation of binary mixtures using deterministic lateral-displacement microfluidic separation systems as well as to comment on the collision frequencies when the arrays of posts are utilized as immunocapture devices.

Risbud, Sumedh R.; Drazer, German

2014-07-01

267

Directional locking in deterministic lateral-displacement microfluidic separation systems.  

PubMed

We analyze the trajectory of suspended spherical particles moving through a square array of obstacles, in the deterministic limit and at zero Reynolds number. We show that in the dilute approximation of widely separated obstacles, the average motion of the particles is equivalent to the trajectory followed by a point particle moving through an array of obstacles with an effective radius. The effective radius accounts for the hydrodynamic as well as short-range repulsive nonhydrodynamic interactions between the suspended particles and the obstacles, and is equal to the critical offset at which particle trajectories become irreversible. Using this equivalent system we demonstrate the presence of directional locking in the trajectory of the particles and derive an inequality that accurately describes the "devil's staircase" type of structure observed in the migration angle as a function of the forcing direction. We use these results to determine the optimum resolution in the fractionation of binary mixtures using deterministic lateral-displacement microfluidic separation systems as well as to comment on the collision frequencies when the arrays of posts are utilized as immunocapture devices. PMID:25122298

Risbud, Sumedh R; Drazer, German

2014-07-01

268

Coolant quality for magnetic resonance imaging systems  

Microsoft Academic Search

As radiologists demand increased power, speed and duty cycle from their magnetic resonance imaging (MRI) systems, thermal management of the gradient sub-system becomes more challenging. A heat exchanger in the MRI system cools heat-generating components by pumping water through hollow copper tubing, which also carries high electrical currents. Water is used as a coolant because of its high specific heat

Julie Wong; Garron K Morris

2008-01-01

269

Knolle Magnetrans: A magnetically levitated train system  

Microsoft Academic Search

The Knolle Magnetrans is a continuous transportation system featuring small cars traveling in rapid succession, levitated by permanent magnets in repulsion, and propelled by stationary linear induction motors. The vehicles' headway, speed, acceleration, and deceleration are designed into the system and mechanically enforced. Passengers board dynamically and controls consist of a simple on-off relay. This paper summarizes the system design

Ernst G. Knolle

1992-01-01

270

Magnetic Launch Assist System-Artist's Concept  

NASA Technical Reports Server (NTRS)

This illustration is an artist's concept of a Magnetic Launch Assist System, formerly referred as the Magnetic Levitation (Maglev) system, for space launch. Overcoming the grip of Earth's gravity is a supreme challenge for engineers who design rockets that leave the planet. Engineers at the Marshall Space Flight Center have developed and tested Magnetic Launch Assist System technologies that could levitate and accelerate a launch vehicle along a track at high speeds before it leaves the ground. Using electricity and magnetic fields, a Magnetic Launch Assist system would drive a spacecraft along a horizontal track until it reaches desired speeds. A full-scale, operational track would be about 1.5-miles long and capable of accelerating a vehicle to 600 mph in 9.5 seconds. The major advantages of launch assist for NASA launch vehicles is that it reduces the weight of the take-off, landing gear and the wing size, as well as the elimination of propellant weight resulting in significant cost savings. The US Navy and the British MOD (Ministry of Defense) are planning to use magnetic launch assist for their next generation aircraft carriers as the aircraft launch system. The US Army is considering using this technology for launching target drones for anti-aircraft training.

1999-01-01

271

DOE/Simplec magnetic susceptibility logging system  

SciTech Connect

A magnetic susceptibility logging system has been developed which is relatively stable under normal field logging conditions and which produces logs that accurately represent in situ variations in magnetic susceptibility. However, both field and laboratory tests indicate the need for further improvement of temperature stabilization and bridge compensation; a new generation system designed by Simplec may fill that need. A cubic granite block with a magnetic susceptibility of 385 ..mu..CGS is designated as the primary calibration standard and is available for public use at the DOE facility in Grand Junction, Colorado. Models are also available for characterization of magnetic susceptibility systems. These include models to provide borehole size correction factors, thin layer interpretation parameters, reproducibility limits, longitudinal resolution, and radius of investigation. The DOE/Simplec system has a 99-percent radius of investigation, approximately equal to the coil length (15 inches), and a 99-percent thickness of investigation, approximately equal to two coil lengths. The true magnetic susceptibility and thickness of isolated layers less than two coil lengths in thickness can be obtained through use of parameters measured from their log responses. Field tests show that the system has a reproducibility of at least 5 ..mu..CGS and that logging at 25 ft/min is a good compromise between speed of operation and keeping the probe on the sidewall. Comparison of log and core magnetic susceptibility measurements confirms the fact that the logging system samples a rather large volume and that interpretive aids are necessary to unfold the true variation of magnetic susceptibility with depth. Finally, logs from known uranium-favorable environments show that magnetic susceptibility measurements can give an indication of the degree of geochemical alteration, which is one of the uranium-favorable haloes sought by exploration geologists.

Emilia, D.A.; Allen, J.W.; Chessmore, R.B.; Wilson, R.B.

1981-03-01

272

Magnetic systems for fusion devices  

SciTech Connect

Mirror experiments have led the way in applying superconductivity to fusion research because of unique requirements for high and steady magnetic fields. The first significant applications were Baseball II at LLNL and IMP at ORNL. More recently, the MFTF-B yin-yang coil was successfully tested and the entire tandem configuration is nearing completion. Tokamak magnets have also enjoyed recent success with the large coil project tests at ORNL, preceded by single coil tests in Japan and Germany. In the USSR, the T-7 Tokamak has been operational for many years and the T-15 Tokamak is under construction, with the TF coils nearing completion. Also the Tore Supra is being built in France.

Henning, C.D.

1985-02-01

273

Hall Conductivity for Two Dimensional Magnetic Systems  

E-print Network

A Kubo inspired formalism is proposed to compute the longitudinal and transverse dynamical conductivities of an electron in a plane (or a gas of electrons at zero temperature) coupled to the potential vector of an external local magnetic field, with the additional coupling of the spin degree of freedom of the electron to the local magnetic field (Pauli Hamiltonian). As an example, the homogeneous magnetic field Hall conductivity is rederived. The case of the vortex at the origin is worked out in detail. This system happens to display a transverse Hall conductivity ($P$ breaking effect) which is subleading in volume compared to the homogeneous field case, but diverging at small frequency like $1/\\omega^2$. A perturbative analysis is proposed for the conductivity in the random magnetic impurity problem (Poissonian vortices in the plane). At first order in perturbation theory, the Hall conductivity displays oscillations close to the classical straight line conductivity of the mean magnetic field.

Jean Desbois; Stéphane Ouvry; Christophe Texier

1996-12-09

274

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

PubMed Central

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. PMID:20122252

2010-01-01

275

Blood progenitor cell separation from clinical leukapheresis product by magnetic nanoparticle binding and magnetophoresis.  

PubMed

Positive selection of CD34+ blood progenitor cells from circulation has been reported to improve patient recovery in applications of autologous transplantation. Current magnetic separation methods rely on cell capture and release on solid supports rather than sorting from flowing suspensions, which limits the range of therapeutic applications and the process scale up. We tested CD34+ cell immunomagnetic labeling and isolation from fresh leukocyte fraction of peripheral blood (leukapheresis) using the continuous quadrupole magnetic flow sorter (QMS), consisting of a flow channel (SHOT, Greenville, IN) and a quadrupole magnet with a maximum field intensity (B(o)) of 1.42 T and a mean force field strength (S(m)) of 1.45 x 10(8) TA/m(2). Both the sample magnetophoretic mobility (m) and the inlet and outlet flow patterns highly affect the QMS performance. Seven commercial progenitor cell labeling reagent combinations were quantitatively evaluated by measuring magnetophoretic mobility of a high CD34 expression cell line, KG-1a, using the cell tracking velocimeter (CTV). The CD34 Progenitor Cell Isolation Kit (Miltenyi Biotec, Bergisch Gladbach, Germany) showed the strongest labeling of KG-1a cells and was selected for progenitor cell enrichment from 11 fresh and 11 cryopreserved clinical leukapheresis samples derived from different donors. The CD34+ cells were isolated with a purity of 60-96%, a recovery of 18-60%, an enrichment rate of 12-169, and a throughput of (1.7-9.3) x 10(4) cells/s. The results also showed a highly regular dependence of the QMS performance on the flow conditions that agreed with the theoretical predictions based on the CD34+ cell magnetophoretic mobility. PMID:17009321

Jing, Ying; Moore, Lee R; Williams, P Stephen; Chalmers, Jeffrey J; Farag, Sherif S; Bolwell, Brian; Zborowski, Maciej

2007-04-15

276

Combined air stripper/membrane vapor separation systems. Final report  

SciTech Connect

Air stripping is an economical and efficient method of removing dissolved volatile organic compounds (VOCs) from contaminated groundwater. Air strippers, however, produce a vent air stream, which must meet the local air quality limits. If the VOC content exceeds the limits, direct discharge is not possible; therefore, a carbon adsorption VOC capture system is used to treat the vent air. This treatment step adds a cost of at least $50/lb of VOC captured. In this program, a combined air stripper/membrane vapor separation system was constructed and demonstrated in the laboratory. The membrane system captures VOCs from the stripper vent stream at a projected cost of $15/lb VOC for a water VOC content of 5 ppmw, and $75/lb VOC for a water VOC content of 1 ppmw. The VOCs are recovered as a small, concentrated liquid fraction for disposal or solvent recycling. The concept has been demonstrated in experiments with a system capable of handling up to 150,000 gpd of water. The existing demonstration system is available for field tests at a DOE facility or remediation site. Replacement of the current short air stripping tower (effective height 3 m) with a taller tower is recommended to improve VOC removal.

Wijmans, J.G.; Baker, R.W.; Kamaruddin, H.D.; Kaschemekat, J.; Olsen, R.P.; Rose, M.E.; Segelke, S.V.

1992-11-01

277

An autonomous surveillance system for blind sources localization and separation  

NASA Astrophysics Data System (ADS)

This paper aims at developing a new technology that will enable one to conduct an autonomous and silent surveillance to monitor sound sources stationary or moving in 3D space and a blind separation of target acoustic signals. The underlying principle of this technology is a hybrid approach that uses: 1) passive sonic detection and ranging method that consists of iterative triangulation and redundant checking to locate the Cartesian coordinates of arbitrary sound sources in 3D space, 2) advanced signal processing to sanitizing the measured data and enhance signal to noise ratio, and 3) short-time source localization and separation to extract the target acoustic signals from the directly measured mixed ones. A prototype based on this technology has been developed and its hardware includes six B and K 1/4-in condenser microphones, Type 4935, two 4-channel data acquisition units, Type NI-9234, with a maximum sampling rate of 51.2kS/s per channel, one NI-cDAQ 9174 chassis, a thermometer to measure the air temperature, a camera to view the relative positions of located sources, and a laptop to control data acquisition and post processing. Test results for locating arbitrary sound sources emitting continuous, random, impulsive, and transient signals, and blind separation of signals in various non-ideal environments is presented. This system is invisible to any anti-surveillance device since it uses the acoustic signal emitted by a target source. It can be mounted on a robot or an unmanned vehicle to perform various covert operations, including intelligence gathering in an open or a confined field, or to carry out the rescue mission to search people trapped inside ruins or buried under wreckages.

Wu, Sean; Kulkarni, Raghavendra; Duraiswamy, Srikanth

2013-05-01

278

Dynamically stable magnetic suspension/bearing system  

DOEpatents

A magnetic bearing system contains magnetic subsystems which act together to support a rotating element in a state of dynamic equilibrium. However, owing to the limitations imposed by Earnshaw's Theorem, the magnetic bearing systems to be described do not possess a stable equilibrium at zero rotational speed. Therefore, mechanical stabilizers are provided, in each case, to hold the suspended system in equilibrium until its speed has exceeded a low critical speed where dynamic effects take over, permitting the achievement of a stable equilibrium for the rotating object. A state of stable equilibrium is achieved above a critical speed by use of a collection of passive elements using permanent magnets to provide their magnetomotive excitation. The magnetic forces exerted by these elements, when taken together, levitate the rotating object in equilibrium against external forces, such as the force of gravity or forces arising from accelerations. At the same time, this equilibrium is made stable against displacements of the rotating object from its equilibrium position by using combinations of elements that possess force derivatives of such magnitudes and signs that they can satisfy the conditions required for a rotating body to be stably supported by a magnetic bearing system over a finite range of those displacements.

Post, Richard F. (Walnut Creek, CA)

1996-01-01

279

Dynamically stable magnetic suspension/bearing system  

DOEpatents

A magnetic bearing system contains magnetic subsystems which act together to support a rotating element in a state of dynamic equilibrium. However, owing to the limitations imposed by Earnshaw`s Theorem, the magnetic bearing systems to be described do not possess a stable equilibrium at zero rotational speed. Therefore, mechanical stabilizers are provided, in each case, to hold the suspended system in equilibrium until its speed has exceeded a low critical speed where dynamic effects take over, permitting the achievement of a stable equilibrium for the rotating object. A state of stable equilibrium is achieved above a critical speed by use of a collection of passive elements using permanent magnets to provide their magnetomotive excitation. The magnetic forces exerted by these elements, when taken together, levitate the rotating object in equilibrium against external forces, such as the force of gravity or forces arising from accelerations. At the same time, this equilibrium is made stable against displacements of the rotating object from its equilibrium position by using combinations of elements that possess force derivatives of such magnitudes and signs that they can satisfy the conditions required for a rotating body to be stably supported by a magnetic bearing system over a finite range of those displacements. 32 figs.

Post, R.F.

1996-02-27

280

Charged particle response of magnetic deflection system for Galileo Jupiter orbiter  

Microsoft Academic Search

A simulation of a magnetic spectrometer system and the study of its instrumental response are presented here. An analytic, three-dimensional expression for the inhomogeneous and fringing magnetic field of the system is obtained. A three-dimensional, time-reversed trajectory calculation of electrons and protons inside the system is performed. A clean electron-ion separation and electron analysis are achieved. The geometric factors of

Yue Wu; Thomas P. Armstrong

1998-01-01

281

Charged particle response of magnetic deflection system for Galileo Jupiter orbiter  

Microsoft Academic Search

A simulation of a magnetic spectrometer system and the study of its instrumental response are presented here. An analytic, three-dimensional expression for the inhomogeneous and fringing magnetic field of the system is obtained. A three-dimensional, time-reversed trajectory calculation of electrons and protons inside the system is performed. A clean electron-ion separation and electron analysis are achieved. The geometric factors of

Yue Wu; Thomas P. Armstrong

1988-01-01

282

Magnetic Field Response Measurement Acquisition System  

NASA Technical Reports Server (NTRS)

A measurement acquisition method that alleviates many shortcomings of traditional measurement systems is presented in this paper. The shortcomings are a finite number of measurement channels, weight penalty associated with measurements, electrical arcing, wire degradations due to wear or chemical decay and the logistics needed to add new sensors. The key to this method is the use of sensors designed as passive inductor-capacitor circuits that produce magnetic field responses. The response attributes correspond to states of physical properties for which the sensors measure. A radio frequency antenna produces a time-varying magnetic field used to power the sensor and receive the magnetic field response of the sensor. An interrogation system for discerning changes in the sensor response is presented herein. Multiple sensors can be interrogated using this method. The method eliminates the need for a data acquisition channel dedicated to each sensor. Methods of developing magnetic field response sensors and the influence of key parameters on measurement acquisition are discussed.

Woodard, Stanley E.; Taylor, Bryant D.; Shams, Qamar A.; Fox, Robert L.

2005-01-01

283

Magnetically Coupled Adjustable Speed Drive Systems  

SciTech Connect

Adjustable speed drive (ASD) technologies have the ability to precisely control motor sytems output and produce a numbr of benefits including energy and demand savings. This report examines the performance and cost effectiveness of a specific class of ASDs called magnetically-coupled adjustable speed drives (MC-ASD) which use the strength of a magnetic field to control the amount of torque transferred between motor and drive shaft. The MagnaDrive Adjustable Speed Coupling System uses fixed rare-earth magnets and varies the distance between rotating plates in the assembly. the PAYBACK Variable Speed Drive uses an electromagnet to control the speed of the drive

Chvala, William D.; Winiarski, David W.

2002-08-18

284

Separation of Intra- and Extramyocellular Lipid Signals in Proton MR Spectra by Determination of Their Magnetic Field Distribution  

NASA Astrophysics Data System (ADS)

In skeletal musculature intramyocellular (IMCL) and extramyocellular lipids (EMCL) are stored in compartments of different geometry and experience different magnetic field strengths due to geometrical susceptibility effects. The effect is strong enough to—at least partly—separate IMCL and EMCL contributions in 1H MR spectroscopy, despite IMCL and EMCL consisting of the same substances. The assessment of intramyocellular lipid stores in skeletal musculature by 1H MR spectroscopy plays an important role for studying physiological and pathological aspects of lipid metabolism. Therefore, a method using mathematical tools of Fourier analysis is developed to obtain the magnetic field distribution (MFD) from the measured spectra by deconvolution. A reference lipid spectrum is required which was recorded in tibial yellow bone marrow. It is shown that the separation of IMCL contributions can be performed more precisely—compared to other methods—based on the MFD. Examples of deconvolution in model systems elucidate the principle. Applications of the proposed approach on in vivo examinations in m. soleus and m. tibialis anterior are presented. Fitting the IMCL part of the MFD by a Gaussian lineshape with a linewidth kept fixed with respect to the linewidth of creatine and with the assumption of a smooth but not necessarily symmetrical shape for the EMCL part, the only free fit parameter, the amplitude of the IMCL part, is definite and subtraction leads to the EMCL part in the MFD. This procedure is especially justified for the soleus muscle showing a severely asymmetrical distribution which might lead to a marked overestimation of IMCL using common line fitting procedures.

Steidle, G.; Machann, J.; Claussen, C. D.; Schick, F.

2002-02-01

285

A novel CO{sub 2} separation system  

SciTech Connect

Current technologies for capturing CO{sub 2} are in-efficient and expensive. TDA Research objectives are to: Sequester most to all of the CO{sub 2}; Generate electricity at high efficiency and low costs; Usable for GTCC, Fuel Cells, GT and any fossil fuel (after gasification or other pre-treatment). Their approach is to Use a chemical sorbent to transfer the energy in the fossil fuel to heat air in a power generation cycle; Condense the water; and to use their Sorbent Energy Transfer System (SETS) which is described in the paper. No Additional Energy Required for CO{sub 2} Separation, they oxidize the fuel in two steps for the same net reaction: full oxidation of the fuel to water and CO{sub 2}.

Copeland, R.J.

2001-01-15

286

Large-gap magnetic suspension systems  

NASA Technical Reports Server (NTRS)

The classification of magnetic suspension devices into small-gap and large-gap categories is addressed. The relative problems of position sensing, control systems, power supplies, electromagnets, and magnetic field or force analysis are discussed. The similarity of all systems from a controls standpoint is qualified. Some applications where large-gap technology is being applied to systems with a physically small air-gap are mentioned. Finally, the applicability of some other suspension approaches, such as electrodynamic or superconducting are briefly addressed.

Britcher, Colin P.

1992-01-01

287

Knolle Magnetrans: A magnetically levitated train system  

NASA Astrophysics Data System (ADS)

The Knolle Magnetrans is a continuous transportation system featuring small cars traveling in rapid succession, levitated by permanent magnets in repulsion, and propelled by stationary linear induction motors. The vehicles' headway, speed, acceleration, and deceleration are designed into the system and mechanically enforced. Passengers board dynamically and controls consist of a simple on-off relay. This paper summarizes the system design goals, describes the system components and discusses related environmental issues.

Knolle, Ernst G.

1992-05-01

288

Nonlinear Control of a Magnetic Levitation System  

Microsoft Academic Search

In this paper the identification, analysis, design and implementation of a controller for the ECP730 magnetic levitation system is presented. The system model, which presents interesting structural properties reported here for the first time, is nonlinear and hence a feedback linearization approach is used. In addition, an external control loop with an integral factor is used to achieve zero steady

Jesus Liceaga-Castro; Diana Hernandez-Alcantara; Luis Amezquita-Brooks

2009-01-01

289

Yoke-free magnetic system for low field studies in magnetically affected reaction yield spectroscopy  

Microsoft Academic Search

The article reports the development of a specialized magnetic system for application in low field studies of chemical reactions involving paramagnetic intermediates. We have designed and built a yoke-free magnetic system optimized for creating rather low static homogeneous magnetic fields that can be cleanly swept through zero value. The actually built system creates magnetic field in the range from ``-500''

Evgeny V. Kalneus; Dmitri V. Stass; Yuri A. Grishin

2005-01-01

290

Computational analysis of enhanced magnetic bioseparation in microfluidic systems with flow-invasive magnetic elements.  

PubMed

A microfluidic design is proposed for realizing greatly enhanced separation of magnetically-labeled bioparticles using integrated soft-magnetic elements. The elements are fixed and intersect the carrier fluid (flow-invasive) with their length transverse to the flow. They are magnetized using a bias field to produce a particle capture force. Multiple stair-step elements are used to provide efficient capture throughout the entire flow channel. This is in contrast to conventional systems wherein the elements are integrated into the walls of the channel, which restricts efficient capture to limited regions of the channel due to the short range nature of the magnetic force. This severely limits the channel size and hence throughput. Flow-invasive elements overcome this limitation and enable microfluidic bioseparation systems with superior scalability. This enhanced functionality is quantified for the first time using a computational model that accounts for the dominant mechanisms of particle transport including fully-coupled particle-fluid momentum transfer. PMID:24931437

Khashan, S A; Alazzam, A; Furlani, E P

2014-01-01

291

Computational Analysis of Enhanced Magnetic Bioseparation in Microfluidic Systems with Flow-Invasive Magnetic Elements  

PubMed Central

A microfluidic design is proposed for realizing greatly enhanced separation of magnetically-labeled bioparticles using integrated soft-magnetic elements. The elements are fixed and intersect the carrier fluid (flow-invasive) with their length transverse to the flow. They are magnetized using a bias field to produce a particle capture force. Multiple stair-step elements are used to provide efficient capture throughout the entire flow channel. This is in contrast to conventional systems wherein the elements are integrated into the walls of the channel, which restricts efficient capture to limited regions of the channel due to the short range nature of the magnetic force. This severely limits the channel size and hence throughput. Flow-invasive elements overcome this limitation and enable microfluidic bioseparation systems with superior scalability. This enhanced functionality is quantified for the first time using a computational model that accounts for the dominant mechanisms of particle transport including fully-coupled particle-fluid momentum transfer. PMID:24931437

Khashan, S. A.; Alazzam, A.; Furlani, E. P.

2014-01-01

292

Drive systems with permanent magnet synchronous motors  

SciTech Connect

This article reports that simulations indicate that a 15% longer electric-vehicle driving range is possible with permanent magnet synchronous motor drive systems compared with asynchronous types. The simplified driveline made possible by a permanent magnet design more than offsets its extra cost. A number of electric-motor types are suitable for electric-vehicle drive systems, one being the permanent magnet (PM) motor. The available of powerful PM materials, the choice of a high number of poles, and the possibility of field weakening are all essential factors for high-performance PM motors. Except for the magnets, PM motor designs are similar to other types of ac motors, and can use the same inverters as other ac motors. Tests and simulations of vehicle drive cycles have indicated that a substantially greater driving range is possible when PM motor drive systems are used. Due to the magnets, the cost of such systems is somewhat higher, but this can be compensated for by improved performance and simplified installation.

Eriksson, S.

1995-02-01

293

A new MAGLEV system for magnetically levitated carrier system  

Microsoft Academic Search

A power-saving electromagnetic suspension system has been developed in which electromagnets with permanent magnets are used to suspend the vehicle. The electromagnets are controlled to maintain air gap length so that the attractive force by the permanent magnet always balances the total weight of the vehicle and its loads, based on modern control theory. This technology realizes a significantly power-saving

Mimpei Morishita; Teruo Azukizawa; Shuji Kanda; Noburu Tamura; Toyohiko Yokoyama

1989-01-01

294

Magnetic Field Response Measurement Acquisition System  

NASA Technical Reports Server (NTRS)

Magnetic field response sensors designed as passive inductor-capacitor circuits produce magnetic field responses whose harmonic frequencies correspond to states of physical properties for which the sensors measure. Power to the sensing element is acquired using Faraday induction. A radio frequency antenna produces the time varying magnetic field used for powering the sensor, as well as receiving the magnetic field response of the sensor. An interrogation architecture for discerning changes in sensor s response kequency, resistance and amplitude is integral to the method thus enabling a variety of measurements. Multiple sensors can be interrogated using this method, thus eliminating the need to have a data acquisition channel dedicated to each sensor. The method does not require the sensors to be in proximity to any form of acquisition hardware. A vast array of sensors can be used as interchangeable parts in an overall sensing system.

Woodard, Stanley E. (Inventor); Taylor, Bryant D. (Inventor); Shams, Qamar A. (Inventor); Fox, Robert L. (Inventor); Fox, Christopher L. (Inventor); Fox, Melanie L. (Inventor); Bryant, Robert G. (Inventor)

2006-01-01

295

A centrifugal elutriation system of separating small numbers of cells.  

PubMed

One of the major disadvantages of centrifugal elutriation (CE) is the relatively large volume (150 ml) of the various fractions, especially if small numbers of cells have to be separated and the fractions contain few cells. To reduce the volume of the fractions 2 elutriator rotors were coupled in series. Since the rotor speed of the second rotor was always kept 750 rpm higher than that of the first rotor, cells elutriated from rotor 1 were collected in rotor 2. After elutriation of a complete fraction from rotor 1, and collection in rotor 2, the cells were harvested from rotor 2. This was achieved by means of a flow distribution unit (FDU), which made it possible to disconnect the flow of both rotors and simultaneously reverse the flow of the second rotor. It is demonstrated that 40-95 X 10(6) mononuclear leukocytes may be fractionated without loss of resolution in fractions of only 9 ml. The lymphocyte (greater than 99%) and monocyte subpopulations (88-94%) obtained were as pure as with CE carried out with only 1 rotor. In addition, the cells in rotor 2 could be washed and suspended in culture medium prior to harvesting by means of the FDU. In this way loss of cells by additional centrifugation steps was avoided. Erythrocytes (RBC) present in certain lymphocyte fractions were lysed with NH4Cl and after lysis of the RBC and elution of ghosts and debris, the cells were washed and harvested. This procedure did not affect cell viability and the PHA response of the lymphocytes. The versatile system described made it possible to apply CE for the separation of small numbers of cells without loss of resolution, and demonstrated that CE is ideally suitable for concentration and washing of cells, and removal of contaminating RBC, not affecting the recovery, viability and function of the cells. PMID:6707482

Figdor, C G; Van Es, W L; Leemans, J M; Bont, W S

1984-03-30

296

LHC II system sensitivity to magnetic fluids  

NASA Astrophysics Data System (ADS)

Experiments have been designed to reveal the influences of ferrofluid treatment and static magnetic field exposure on the photosynthetic system II, where the light harvesting complex (LHC II) controls the ratio chlorophyll a/ chlorophyll b (revealing, indirectly, the photosynthesis rate). Spectrophotometric measurement of chlorophyll content revealed different influences for relatively low ferrofluid concentrations (10-30 ?l/l) in comparison to higher concentrations (70-100 ?l/l). The overlapped effect of the static magnetic field shaped better the stimulatory ferrofluid action on LHC II system in young poppy plantlets.

Cotae, Vlad; Creanga, Ioan

2005-03-01

297

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

EPA Science Inventory

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...

298

Two new young, wide, magnetic + non-magnetic double-degenerate binary systems  

NASA Astrophysics Data System (ADS)

We report the discovery of two, new, rare, wide, double-degenerate binaries that each contain a magnetic and a non-magnetic star. The components of SDSS J092646.88+132134.5 + J092647.00+132138.4 and of SDSS J150746.48+521002.1 + J150746.80+520958.0 have angular separations of only 4.6 arcsec (a˜ 650 au) and 5.1 arcsec (a˜ 750 au), respectively. They also appear to share common proper motions. Follow-up optical spectroscopy has revealed each system to consist of a DA and a H-rich high-field magnetic white dwarf (HFMWD). Our measurements of the effective temperatures and the surface gravities of the DA components reveal both to have larger masses than is typical of field white dwarfs. By assuming that these degenerates have evolved essentially as single stars, owing to their wide orbital separations, we can use them to place limits on the total ages of the stellar systems. These suggest that in each case the HFMWD is probably associated with an early-type progenitor (Minit > 2 M?). We find that the cooling time of SDSS J150746.80+520958.0 (DAH) is lower than might be expected had it followed the evolutionary path of a typical single star. This mild discord is in the same sense as that observed for two of the small number of other HFMWDs for which progenitor mass estimates have been made, RE J0317-853 and EG 59. The mass of the other DAH, SDSS J092646.88+132134.5, appears to be smaller than expected on the basis of single-star evolution. If this object was/is a member of a hierarchical triple system it may have experienced greater mass loss during an earlier phase of its life as a result of its having a close companion. The large uncertainties on our estimates of the parameters of the HFMWDs suggest that a larger sample of these objects is required to firmly identify any trends in their inferred cooling times and progenitor masses. This should shed further light on their formation and on the impact magnetic fields have on the late stages of stellar evolution. To serve as a starting point, we highlight two further candidate young, wide magnetic + non-magnetic double-degenerate systems within SDSS, CBS 229 and SDSS J074853.07+302543.5 + J074852.95+302543.4, which should be subjected to detailed (resolved) spectroscopic follow-up studies.

Dobbie, P. D.; Baxter, R.; Külebi, B.; Parker, Q. A.; Koester, D.; Jordan, S.; Lodieu, N.; Euchner, F.

2012-03-01

299

Magnetic Field Response Measurement Acquisition System  

NASA Technical Reports Server (NTRS)

This paper presents a measurement acquisition method that alleviates many shortcomings of traditional measurement systems. The shortcomings are a finite number of measurement channels, weight penalty associated with measurements, electrical arcing, wire degradations due to wear or chemical decay and the logistics needed to add new sensors. Wire degradation has resulted in aircraft fatalities and critical space launches being delayed. The key to this method is the use of sensors designed as passive inductor-capacitor circuits that produce magnetic field responses. The response attributes correspond to states of physical properties for which the sensors measure. Power is wirelessly provided to the sensing element by using Faraday induction. A radio frequency antenna produces a time-varying magnetic field used to power the sensor and receive the magnetic field response of the sensor. An interrogation system for discerning changes in the sensor response frequency, resistance and amplitude has been developed and is presented herein. Multiple sensors can be interrogated using this method. The method eliminates the need for a data acquisition channel dedicated to each sensor. The method does not require the sensors to be near the acquisition hardware. Methods of developing magnetic field response sensors and the influence of key parameters on measurement acquisition are discussed. Examples of magnetic field response sensors and the respective measurement characterizations are presented. Implementation of this method on an aerospace system is discussed.

Woodard, Stanley E.; Taylor,Bryant D.; Shams, Qamar A.; Fox, Robert L.

2007-01-01

300

Systems and methods for separating a multiphase fluid  

NASA Technical Reports Server (NTRS)

Apparatus and methods for separating a fluid are provided. The apparatus can include a separator and a collector having an internal volume defined at least in part by one or more surfaces narrowing toward a bottom portion of the volume. The separator can include an exit port oriented toward the bottom portion of the volume. The internal volume can receive a fluid expelled from the separator into a flow path in the collector and the flow path can include at least two directional transitions within the collector.

Weislogel, Mark M. (Inventor); Thomas, Evan A. (Inventor); Graf, John C. (Inventor)

2011-01-01

301

On-chip magnetic separation and encapsulation of cells in droplets.  

PubMed

Single cell study is gaining importance because of the cell-to-cell variation that exists within cell population, even after significant initial sorting. Analysis of such variation at the gene expression level could impact single cell functional genomics, cancer, stem-cell research, and drug screening. The on-chip monitoring of individual cells in an isolated environment would prevent cross-contamination, provide high recovery yield, and enable study of biological traits at a single cell level. These advantages of on-chip biological experiments is a significant improvement for a myriad of cell analyses methods, compared to conventional methods, which require bulk samples and provide only averaged information on cell structure and function. We report on a device that integrates a mobile magnetic trap array with microfluidic technology to provide the possibility of separation of immunomagnetically labeled cells and their encapsulation with reagents into picoliter droplets for single cell analysis. The simultaneous reagent delivery and compartmentalization of the cells immediately following sorting are all performed seamlessly within the same chip. These steps offer unique advantages such as the ability to capture cell traits as originated from its native environment, reduced chance of contamination, minimal use of the reagents, and tunable encapsulation characteristics independent of the input flow. Preliminary assay on cell viability demonstrates the potential for the device to be integrated with other up- or downstream on-chip modules to become a powerful single-cell analysis tool. PMID:23370785

Chen, Aaron; Byvank, Tom; Chang, Woo-Jin; Bharde, Atul; Vieira, Greg; Miller, Brandon L; Chalmers, Jeffrey J; Bashir, Rashid; Sooryakumar, Ratnasingham

2013-03-21

302

Synthesis, characterization and photocatalytic activity of magnetically separable hexagonal Ni/ZnO nanostructure.  

PubMed

The hexagonal zinc oxide coated nickel (Ni/ZnO) nanostructure photocatalyst has successfully been prepared by the reduction of nickel chloride hexahydrate using hydrazine hydrate through the solvothermal process at 140 °C followed by surface modification of the product by the reflux method at 110 °C for 1 h. The X-ray diffraction (XRD) pattern showed that the 'as prepared' sample consists of face centered cubic Ni and hexagonal wurtzite ZnO without any traces of impurity. Field emission scanning electron microscopy (FESEM) and transmission electron microscopy (TEM) images confirmed the formation of nickel nanoparticles under solvothermal conditions. These nickel nanoparticles, when subjected to reflux, formed the hexagonal zinc oxide coated nickel nanostructure. Fourier transform infrared (FTIR) spectra, photoluminescence (PL) and Raman studies also confirmed the presence of zinc oxide in the hybrid nanostructure. The growth mechanism for the development of the hexagonal zinc oxide coated nickel (Ni/ZnO) nanostructure has also been proposed. The appearance of the hysteresis loop, in the as-prepared Ni/ZnO hybrid nanostructure, demonstrated its ferromagnetic character at room temperature. The hexagonal Ni/ZnO nanostructure also acts as an efficient photocatalyst in the degradation of methylene blue under ultraviolet light irradiation. It is observed that the catalytic efficiency of the hybrid nanocatalyst is better compared to pure zinc oxide. Most importantly, the Ni/ZnO catalyst could also be easily separated, simply by applying an external magnetic field, and reused. PMID:22975724

Senapati, Samarpita; Srivastava, Suneel K; Singh, Shiv B

2012-10-21

303

Chemical interferences when using high gradient magnetic separation for phosphate removal: consequences for lake restoration.  

PubMed

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 (conductivities<600 ? S cm(-1)). However, a significant reduction in P removal was observed for extremely high 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

de Vicente, I; Merino-Martos, A; Guerrero, F; Amores, V; de Vicente, J

2011-09-15

304

Magnetic phase separation in LaMn1-xFexO3+y  

NASA Astrophysics Data System (ADS)

We have investigated the LaMn1-xFexO3+y system in the whole range of 0<=x<=1, for polycrystalline samples prepared by solid state reaction in air. All samples show orthorhombic structure (space group Pnma). For x=0 the oxygen excess, estimated to be y ˜ 0.1, produces vacancies in the La and Mn sites and generates a fraction around 20% of Mn^4+ ions (3t2g) and 80% of the usual Mn^3+ ions (3t2g, 1eg), with possible double exchange interaction between them. The Fe-doping in this system is known to produce only stable Fe^3+ ions (3t2g, 2eg). We find an evolution from a fairly strong ferromagnetic (FM) behavior, with saturation magnetization (T=2K) mS ˜ 4 ?B and Curie temperature Tc ˜ 160 K, for x=0, to an antiferromagnetic (AFM) behavior, with TN=790 K, for x=1. For intermediate Fe contents a mixed phase scenario occurs, with a gradual decrease (increase) of the FM (AFM) phase, accompanied by a systematic transition broadening for 0.2magnetic-ion types, accounts very well for the mS dependence on Fe doping.

de Lima, O. F.; Coaquira, J. A. H.; de Almeida, R. L.; de Carvalho, L. B.; Malik, S. K.

2008-03-01

305

Magnetic Thin Films for Perpendicular Magnetic Recording Systems  

NASA Astrophysics Data System (ADS)

In the advanced information society of today, information storage technology, which helps to store a mass of electronic data and offers high-speed random access to the data, is indispensable. Against this background, hard disk drives (HDD), which are magnetic recording devices, have gained in importance because of their advantages in capacity, speed, reliability, and production cost. These days, the uses of HDD extend not only to personal computers and network servers but also to consumer electronics products such as personal video recorders, portable music players, car navigation systems, video games, video cameras, and personal digital assistances.

Sugiyama, Atsushi; Hachisu, Takuma; Osaka, Tetsuya

306

An intelligent digital magnetic recording system (DIMARS)  

NASA Astrophysics Data System (ADS)

The system consists of three magnetic variometers with electrical output signals for the H, D, and Z components, a proton magnetometer for the total field, a data acquisition system, two cassette recorders, an analogue chart recorder, a calendar clock, and a telex. The analogue and digital input data are sampled at 10 sec intervals, averaged over a minute, and recorded on a magnetic tape cassette. The computed hourly and daily mean values and the daily minimum and maximum values are recorded together with the occurrence times on a second cassette, at the operator's request. Rapid run recording of the 10 sec values of each measured component is initiated automatically during magnetic storms. DIMARS incorporates several test functions as ROM test, A/D converter test, recorder test, telexline test and checking the memory content. The test functions can be activated by the equipment keyboard, or via the telex. The telex can also be operated as an output printer.

Hegymegi, L.; Drimusz, L.

1984-07-01

307

The internal energies of Heisenberg magnetic systems  

NASA Astrophysics Data System (ADS)

The internal energies, including transverse and longitudinal parts, of quantum Heisenberg systems for arbitrary spin S are investigated by the double-time Green's function method. The expressions for ferromagnetic (FM) and antiferromagnetic (AFM) systems are derived when one-component of magnetization is considered with the higher order longitudinal correlation functions being carefully treated. An unexpected result is that around the order-disorder transition points the neighboring spins in a FM (AFM) system are more likely longitudinally antiparallel (parallel) than parallel (antiparallel) to each other for S?3/2 in spite of the FM (AFM) exchange between the spins. This is attributed to the strong quantum fluctuation of the systems with small S values. We also present the expressions of the internal energies of FM systems when the three-component of magnetizations are considered.

Wang, Huai-Yu; Zhai, Liang-Jun; Qian, Meichun

2014-03-01

308

Paleomagnetic recording fidelity of nonideal magnetic systems  

NASA Astrophysics Data System (ADS)

suite of near-identical magnetite nanodot samples produced by electron-beam lithography have been used to test the thermomagnetic recording fidelity of particles in the 74-333 nm size range; the grain size range most commonly found in rocks. In addition to controlled grain size, the samples had identical particle spacings, meaning that intergrain magnetostatic interactions could be controlled. Their magnetic hysteresis parameters were indicative of particles thought not to be ideal magnetic recorders; however, the samples were found to be excellent thermomagnetic recorders of the magnetic field direction. They were also found to be relatively good recorders of the field intensity in a standard paleointensity experiment. The samples' intensities were all within ˜15% of the expected answer and the mean of the samples within 3% of the actual field. These nonideal magnetic systems have been shown to be reliable records of the geomagnetic field in terms of both direction and intensity even though their magnetic hysteresis characteristics indicate less than ideal magnetic grains.

Muxworthy, Adrian R.; Krása, David; Williams, Wyn; Almeida, Trevor P.

2014-06-01

309

Magnetic field perturbations in the systems where only poloidal magnetic field is present*  

E-print Network

1 Magnetic field perturbations in the systems where only poloidal magnetic field is present* D In some plasma confinement systems the confinement is provided by a poloidal magnetic field (no toroidal magnetic field is present). Examples include FRC, levitated dipoles, and long diffuse pinches. We consider

310

Magnetic Launch Assist System Demonstration Test  

NASA Technical Reports Server (NTRS)

Engineers at the Marshall Space Flight Center (MSFC) have been testing Magnetic Launch Assist Systems, formerly known as Magnetic Levitation (MagLev) technologies. To launch spacecraft into orbit, a Magnetic Launch Assist system would use magnetic fields to levitate and accelerate a vehicle along a track at a very high speed. Similar to high-speed trains and roller coasters that use high-strength magnets to lift and propel a vehicle a couple of inches above a guideway, the launch-assist system would electromagnetically drive a space vehicle along the track. A full-scale, operational track would be about 1.5-miles long and capable of accelerating a vehicle to 600 mph in 9.5 seconds. This photograph shows a subscale model of an airplane running on the experimental track at MSFC during the demonstration test. This track is an advanced linear induction motor. Induction motors are common in fans, power drills, and sewing machines. Instead of spinning in a circular motion to turn a shaft or gears, a linear induction motor produces thrust in a straight line. Mounted on concrete pedestals, the track is 100-feet long, about 2-feet wide, and about 1.5- feet high. The major advantages of launch assist for NASA launch vehicles is that it reduces the weight of the take-off, the landing gear, the wing size, and less propellant resulting in significant cost savings. The US Navy and the British MOD (Ministry of Defense) are planning to use magnetic launch assist for their next generation aircraft carriers as the aircraft launch system. The US Army is considering using this technology for launching target drones for anti-aircraft training.

2001-01-01

311

Autonomous Underwater Vehicle Magnetic Mapping System  

NASA Astrophysics Data System (ADS)

An Autonomous Underwater Vehicle (AUV) Magnetic Mapping (MM) System has been developed and tested for military munitions detection as well as pipeline locating, wreck searches, and geologic surveys in underwater environments. The system is comprised of a high sensitivity Geometrics G-880AUV cesium vapor magnetometer integrated with a Teledyne-Gavia AUV and associated Doppler enabled inertial navigation further utilizing traditional acoustic bathymetric and side scan imaging. All onboard sensors and associated electronics are managed through customized crew members to autonomously operate through the vehicles primary control module. Total field magnetic measurements are recorded with asynchronous time-stamped data logs which include position, altitude, heading, pitch, roll, and electrical current usage. Pre-planned mission information can be uploaded to the system operators to define data collection metrics including speed, height above seafloor, and lane or transect spacing specifically designed to meet data quality objectives for the survey. As a result of the AUVs modular design, autonomous navigation and rapid deployment capabilities, the AUV MM System provides cost savings over current surface vessel surveys by reducing the mobilization/demobilization effort, thus requiring less manpower for operation and reducing or eliminating the need for a surface support vessel altogether. When the system completes its mission, data can be remotely downloaded via W-LAN and exported for use in advanced signal processing platforms. Magnetic compensation software has been concurrently developed to accept electrical current measurements directly from the AUV to address distortions from permanent and induced magnetization effects on the magnetometer. Maneuver and electrical current compensation terms can be extracted from the magnetic survey missions to perform automated post-process corrections. Considerable suppression of system noise has been observed over traditional compensation methods that do not use electrical current terms. Recent demonstrations of the AUV MM System conducted at test plots seeded with inert munitions show reliable detection of 75mm and larger projectiles at altitudes of over 2 meters above the seafloor. Improvement ratios between 11 and 12.4 were observed in the survey data after magnetic compensation, reducing system noise to approximately ±0.25 nano-Tesla. Co-registered side scan sonar images were acquired with the magnetic data to augment target analysis and interpretation. No net drift of the navigation solution was observed during survey missions thus confirming target positional accuracy to better than 1 meter.;

Steigerwalt, R.; Johnson, R. M.; Trembanis, A. C.; Schmidt, V. E.; Tait, G.

2012-12-01

312

Adaptive automatic balancing of magnetic bearing systems  

Microsoft Academic Search

Rotating machinery including magnetic bearings are usually persistently excited by the rotation related disturbances such as mass unbalance; hence there exists a residual vibration in the steady state response even if the closed loop system is asymptotically stable. In order to control the periodic disturbances, a disturbance accommodating controller (DAC) is designed based on the disturbance estimator and applied to

Jong-Sun Kim

1993-01-01

313

Superconducting electromagnets for large wind tunnel magnetic suspension and balance systems  

SciTech Connect

This paper presents a new design study of a Magnetic Suspension and Balance System (MSBS) for airplane models in a large 8 ft x 8 ft wind tunnel. New developments in the design include: use of a superconducting solenoid as a model core instead of magnetized iron; combination of permanent magnet material in the model wings along with four race-track coils to produce the required roll torque; and mounting of all the magnets in an integral cold structure instead of in separate cryostats. Design of superconducting solenoid model cores and practical experience with a small-scale prototype are discussed.

Boom, R.W.; Abdelsalam, M.K.; Bakerek, K.; Britcher, C.P.; Esking, J.; Eyssa, Y.M.; Goodyer, M.J.; McIntosh, G.E.; Scurlock, R.G.; Wu, Y.Y.

1985-03-01

314

System characterization of a magnetically suspended flywheel  

NASA Technical Reports Server (NTRS)

The purpose of flywheel energy storage is to provide a means to save energy during times when the satellite is in sunlight, and then return the energy during the time when the satellite is in darkness. Typically, an energy storage device operates cyclically, where for satellites in Low Earth Orbit (LEO) the typical period is 60 minutes of sunlight followed by 30 minutes of darkness. If a lifetime of 17 years is required the energy storage system must be capable of sustaining approximately 100,000 cycles. The recent developments at the University of Maryland and how these progressions apply to a 500 Watt-hour magnetically suspended flywheel stack energy storage system are covered. The work includes hardware testing results from a stack flywheel energy storage system, improvements in the area of non-contacting displacement transducers, and performance enhancements of magnetic bearings. The experimental results show that a stack flywheel energy storage system is a feasible technology.

Kirk, James A.; Anand, Dave K.; Plant, David P.

1988-01-01

315

Design of Countercurrent Separation of Ginkgo biloba Terpene Lactones by Nuclear Magnetic Resonance  

PubMed Central

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

Qiu, Feng; Friesen, Brent J.; McAlpine, James B.; Pauli, Guido F.

2012-01-01

316

STP Textbook Chapter 5: Magnetic Systems  

NSDL National Science Digital Library

We apply the general formalism of statistical mechanics developed in Chapter 4 to the Ising model, a model magnetic system for which the interactions between the magnetic moments are important. We will discover that these interactions lead to a wide range of phenomena, including the existence of phase transitions and other cooperative phenomena. Computer simulation methods will be used extensively and a simple approximation method known as mean-field theory will be introduced. The simulations can be found by searching ComPADRE for Open Source Physics, STP, or Statistical and Thermal Physics.

Gould, Harvey; Tobochnik, Jan

2008-05-28

317

A paper-based surface-enhanced resonance Raman spectroscopic (SERRS) immunoassay using magnetic separation and enzyme-catalyzed reaction.  

PubMed

In this study, a novel paper-based SERRS immunoassay based on magnetic separation and alkaline phosphatase (ALP) enzyme catalyzed hydrolysis reaction was developed. By using modified antibodies conjugated to magnetic beads, capture of mouse IgG followed by addition of ALP-labeled antibodies would form a sandwich-like immunoconjugate. After magnetic separation, 5-bromo-4-chloro-3-indolyl phosphate (BCIP), a low SERRS active compound, was added as the substrate for ALP to generate a high SERRS response. Detection was conducted on a silver colloid/PVP/filter paper SERS substrate by spotting a pre-aggregated silver colloid sol onto polyvinyl pyrrolidone (PVP) modified filter paper using a semi-automatic TLC sample applicator. The optimization of the highly SERS active paper-based substrate, dynamic hydrolysis process of BCIP, quantitative detection of IgG, and selectivity of the assay was studied in detail. By taking advantage of magnetic separation in order to decrease the background interference, the selective enzyme reaction involved in producing a highly SERRS active product could detect mouse IgG from 1 to 500 ng mL(-1) with a LOD of 0.33 ng mL(-1). PMID:23486763

Chen, Yuanyuan; Cheng, Hanwen; Tram, Kha; Zhang, Shengfeng; Zhao, Yanhua; Han, Liyang; Chen, Zengping; Huan, Shuangyan

2013-05-01

318

Separation of drug traces from water with particular membrane systems.  

PubMed

The purpose of the present project is to examine the applicability of certain natural biological and liquid membranes for the separation of drugs of environmental concern such as ibuprofen, diclofenac, carbamazepine, and sulfamethoxazol from dilute aqueous solutions. Different types of intestine parts of cattle, sheep, and pig were applied as biological flat sheet membranes after different modes of pretreatment. Best results were obtained with special parts of cattle appendix. The concentration of each drug in the aqueous feed phase was in the range of 0.1-10 mg (cm3)(-1), the pH-values adjusted between 8 and 10. Pure water was used as the permeation phase. The influence of experimental parameters such as stirring velocity, temperature, pH-value, salt concentration, and the presence of surfactants as well as humic substances was studied. Under all conditions chosen the combined drugs permeate simultaneously through the natural membranes as the permeation kinetics of the individual compounds are very similar, while humic compounds were retained. Additional treatment of the permeate with liquid or solid phase extraction techniques increases crucially the depletion of the drugs from the feed. The mass transfer of the pharmaceuticals through the liquid membranes was carried out in three-compartment transport cells and supported liquid membrane-chambers. The three-phase liquid bulk membrane systems consisted of an aqueous feed solution, an organic solvent (dihexyl ether, decane, undecane, or decanol) with and without a dissolved sulfonic acid, tertiary amine or Cu(II)-chelate compound as a liquid bulk membrane and an aqueous stripping solutions containing dilute solutiuons of Na2CO3, NaOH, HCl, or HClO4. The transport of the drugs shows some differences, which can be attributed to their acid/base-behavior and partition coefficients log Kow. High extraction yields were obtained for sulfamethoxazol and carbamazepine by using polar organic solvents. Maximum transport efficiencies were obtained for the acidic compounds ibuprofen and diclofenac. They were completely extracted by using dihexyl ether loaded with octane sulfonic acid. A pH-gradient between feed and strip increases the efficiency of the transport. Certain three-phase compositions were successfully utilized in supported liquid membrane systems (SLM) so that high enrichment factors (approximately 75) were achieved for traces of diclofenac and ibuprofen. The solid and liquid membrane systems employed aim for technical as well as analytical purposes, such as sample pretreatment prior to HPLC-UV or LC-MS analysis of drug traces. PMID:15137718

Grote, Manfred; Haciosmanoglu, Bedia; Bataineh, Mahmoud; Nolte, Jürgen

2004-01-01

319

Ionic pair complexes with well-separated columnar stack structure based on [Pt(mnt)2]- ions showing unusual magnetic transition: syntheses, crystal structures, and magnetic properties.  

PubMed

Three ion pair complexes, [4-R-benzylpyridinium][bis(maleodinitriledithiolato)platinum(III)] (abbreviated as [RBzPy][Pt(mnt)(2)]; R = Cl (1), Br (2), or NO(2) (3)), have been synthesized. The cations and anions stack into well-separated columns in the solid state, and the Pt(III) ions form a 1-D zigzag chain within a [Pt(mnt)(2)](-) column through Pt...S, S...S, and Pt...S...Pt interactions. The chain is uniform in 1 and 2, while it alternates in 3. Unusual magnetic phase transitions from paramagnetism to diamagnetism were observed in these three complexes at approximately 275 K for 1, approximately 269 K for 2, and approximately 184 K for 3. These phase transitions were also found in DSC measurements for 1 and 2. The overall magnetic behaviors for 1-3 indicate the presence of antiferromagnetic exchange interactions in the high-temperature phase and spin-gapped systems in the low-temperature phase. Below 50 K, 2 exhibits weak ferromagnetism. The spontaneous moments are nearly repressed by a field of 1.0 T. The crystal structure of 2 at 173 K reveals that there are two crystallographically independent [Pt(mnt)(2)](-) entries in an asymmetric unit. These two crystallographically independent [Pt(mnt)(2)](-) entries satisfy the spin-canting condition, and the EPR spectra measured at room temperature exhibit anisotropic character. Therefore, the weak ferromagnetic behavior in the low-temperature region for 2 can be attributed to the spin-canting phenomenon. PMID:15074975

Ren, X M; Okudera, H; Kremer, R K; Song, Y; He, C; Meng, Q J; Wu, P H

2004-04-19

320

Separation and correlation of structural and magnetic roughness in a Ni thin film by polarized off-specular neutron reflectometry  

NASA Astrophysics Data System (ADS)

Diffuse (off-specular) neutron and x-ray reflectometry has been used extensively for the determination of interface morphology in solids and liquids. For neutrons, a novel possibility is off-specular reflectometry with polarized neutrons to determine the morphology of a magnetic interface. There have been few such attempts due to the lower brilliance of neutron sources, though magnetic interaction of neutrons with atomic magnetic moments is much easier to comprehend and easily tractable theoretically. We have obtained a simple and physically meaningful expression, under the Born approximation, for analyzing polarized diffuse (off-specular) neutron reflectivity (PDNR) data. For the first time PDNR data from a Ni film have been analyzed and separate chemical and magnetic morphologies have been quantified. Also specular polarized neutron reflectivity measurements have been carried out to measure the magnetic moment density profile of the Ni film. The fit to PDNR data results in a longer correlation length for in-plane magnetic roughness than for chemical (structural) roughness. The magnetic interface is smoother than the chemical interface.

Singh, Surendra; Basu, Saibal

2009-02-01

321

Towards an electro-magnetic field separation of deposited material implemented in an ion beam sputter process  

SciTech Connect

Nowadays, Ion Beam Sputter (IBS) processes are very well optimized on an empirical basis. To achieve further progresses, a modification of the IBS process by guiding the coating material using an axial magnetic field and an additional electrical field has been studied. The electro-magnetic (EM) field leads to a significant change in plasma properties and deposition rate distributions, whereas an increase in deposition rate along the centerline of the axial EM field around 150% was observed. These fundamental studies on the prototype are the basis for the development of an applicable and workable design of a separation device.

Malobabic, Sina; Jupe, Marco; Ristau, Detlev [Laser Component Department, Laser Zentrum Hannover e.V., Hollerithallee 8, 30149 Hannover (Germany) [Laser Component Department, Laser Zentrum Hannover e.V., Hollerithallee 8, 30149 Hannover (Germany); Quest: Centre of Quantum Engineering and Space-Time Research, Leibniz Universitaet Hannover, Hannover (Germany)

2013-06-03

322

Accretion Flows in Magnetic White Dwarf Systems  

NASA Technical Reports Server (NTRS)

We received Type A and B funding under the NASA Astrophysics Data Program for the analysis and interpretation of hard x-ray data obtained by the Rossi X-ray Timing Explorer and other NASA sponsored missions for Intermediate Polars (IPS) and Polars. For some targets, optical data was available. We reduced and analyzed the X-ray spectra and the X-ray and optical (obtained at the Cerro Tololo Inter-American Observatory) timing data using detailed shock models (which we constructed) to place constraints on the properties of the accreting white dwarfs, the high energy emission mechanisms of white dwarfs, and the large-scale accretion flows of Polars and IPS. IPS and Polars are white dwarf mass-transfer binaries, members of the larger class of cata,clysmic variables. They differ from the bulk of the cataclysmic variables in that they contain strongly magnetic white dwarfs; the white dwarfs in Polars have B, = 7 to 230 MG and those in IPS have B, less than 10 MG. The IPS and Polars are both examples of funneled accretion flows in strong magnetic field systems. The IPS are similar to x-ray pulsars in that accretion disks form in the systems which are disrupted by the strong stellar magnetic fields of the white dwarfs near the stellar surface from where the plasma is funneled to the surface of the white dwarf. The localized hot spots formed at the footpoints of the funnels coupled with the rotation of the white dwarf leads to coherent pulsed x-ray emission. The Polars offer an example of a different accretion topology; the magnetic field of the white dwarf controls the accretion flow from near the inner Lagrangian point of the system directly to the stellar surface. Accretion disks do not form. The strong magnetic coupling generally leads to synchronous orbital/rotational motion in the Polars. The physical system in this sense resembles the Io/Jupiter system. In both IPS and Polars, pulsed emission from the infrared to x-rays is produced as the funneled flows merge onto the white dwarfs through the formation of strong radiating shock waves. A comparative study of the IPS and Polars can elucidate the primary effects of the magnetic fields on the dynamics and thermodynamics in accreting white dwarf systems.

Imamura, James N.

2005-01-01

323

Cost comparisons for SSC magnet dependent systems  

SciTech Connect

An SSC Cost Estimating Task Force was appointed by the SSC Director in May, 1985. The charge to the task force was to perform a detailed review of costs for all superconducting magnet design styles that are under consideration for the SSC. Cost information on five magnet styles was reviewed in detail by the task force members. The basic cost information was developed by participating laboratories and by industry. Details of the procedure and analysis are presented in Chapter III. The purpose of this report is to provide a comparison of all SSC construction project cost information that is dependent on the various magnet styles. It is emphasized that the costs displayed in the tables of this report are not the total costs for an SSC construction project. Only those systems for which costs vary with magnet style are included. In Appendix E, current results are compared with the relevant parts of the 1984 SSC Reference Designs Study (RDS) cost estimate. Following the method used in the RDS, the costs that are developed here are non-site specific. The labor rates utilized are based on a national average for the various labor categories. The Conventional Systems costs for underground structures are derived from an extension of the ``median-site`` model as described in the RDS.

NONE

1985-08-15

324

Reprocessing system with nuclide separation based on chromatography in hydrochloric acid solution  

SciTech Connect

We have proposed the reprocessing system with nuclide separation processes based on the chromatographic technique in the hydrochloric acid solution system. Our proposed system consists of the dissolution process, the reprocessing process, the minor actinide separation process, and nuclide separation processes. In the reprocessing and separation processes, the pyridine resin is used as a main separation media. It was confirmed that the dissolution in the hydrochloric acid solution is easily achieved by the plasma voloxidation and by the addition of oxygen peroxide into the hydrochloric acid solution.

Suzuki, Tatsuya; Tachibana, Yu [Department of Nuclear Safety System Engineering, Nagaoka University of Technology, Nagaoka, Niigata 940-2188 (Japan); Koyama, Shi-ichi [O-oarai Research and Development Center, Japan Atomic Energy Agency, Ooarai, Ibaraki 311-1393 (Japan)

2013-07-01

325

14 CFR 25.1707 - System separation: EWIS.  

...airplane or its systems. (c) Wires and cables carrying heavy current, and...other mechanical control systems cables and associated system components...other mechanical control systems cables or systems components will not...

2014-01-01

326

Persistent currents and magnetization in two-dimensional magnetic quantum systems  

Microsoft Academic Search

Persistent currents and magnetization are considered for a two-dimensional electron (or gas of electrons) coupled to various magnetic fields. Thermodynamic formulae for the magnetization and the persistent current are established and the “classical” relationship between current and magnetization is shown to hold for systems invariant both by translation and rotation. Applications are given, including the point vortex superposed onto an

Jean Desbois; Stéphane Ouvry; Christophe Texier

1998-01-01

327

Separation Anxiety  

NSDL National Science Digital Library

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.

Yu, Julie

2007-01-01

328

GEOPHYSICS, VOL. 63, NO. 2 (MARCH-APRIL 1998); P. 431439, 13 FIGS. Separation of regional and residual magnetic field data  

E-print Network

underground sources. The targets for specific surveys are often small-scale structures buried at shallow and residual magnetic field data Yaoguo Li and Douglas W. Oldenburg ABSTRACT Wepresentamethodforseparatingregionalandresid- ual magnetic fields using a 3-D magnetic inversion al- gorithm. The separation is achieved

Oldenburg, Douglas W.

329

Beam-energy dependence of charge separation along the magnetic field in Au+Au collisions at RHIC.  

PubMed

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

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

330

Beam-energy dependence of charge separation along the magnetic field in Au+Au collisions at RHIC  

E-print Network

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.

STAR Collaboration; L. Adamczyk; J. K. Adkins; G. Agakishiev; M. M. Aggarwal; Z. Ahammed; I. Alekseev; J. Alford; C. D. Anson; A. Aparin; D. Arkhipkin; E. C. Aschenauer; G. S. Averichev; A. Banerjee; D. R. Beavis; R. Bellwied; A. Bhasin; A. K. Bhati; P. Bhattarai; H. Bichsel; J. Bielcik; J. Bielcikova; L. C. Bland; I. G. Bordyuzhin; W. Borowski; J. Bouchet; A. V. Brandin; S. G. Brovko; S. Bültmann; I. Bunzarov; T. P. Burton; J. Butterworth; H. Caines; M. Calderón de la Barca Sánchez; D. Cebra; R. Cendejas; M. C. Cervantes; P. Chaloupka; Z. Chang; S. Chattopadhyay; H. F. Chen; J. H. Chen; L. Chen; J. Cheng; M. Cherney; A. Chikanian; W. Christie; J. Chwastowski; M. J. M. Codrington; G. Contin; J. G. Cramer; H. J. Crawford; X. Cui; S. Das; A. Davila Leyva; L. C. De Silva; R. R. Debbe; T. G. Dedovich; J. Deng; A. A. Derevschikov; R. Derradi de Souza; S. Dhamija; B. di Ruzza; L. Didenko; C. Dilks; F. Ding; P. Djawotho; X. Dong; J. L. Drachenberg; J. E. Draper; C. M. Du; L. E. Dunkelberger; J. C. Dunlop; L. G. Efimov; J. Engelage; K. S. Engle; G. Eppley; L. Eun; O. Evdokimov; O. Eyser; R. Fatemi; S. Fazio; J. Fedorisin; P. Filip; E. Finch; Y. Fisyak; C. E. Flores; C. A. Gagliardi; D. R. Gangadharan; D. Garand; F. Geurts; A. Gibson; M. Girard; S. Gliske; L. Greiner; D. Grosnick; D. S. Gunarathne; Y. Guo; A. Gupta; S. Gupta; W. Guryn; B. Haag; A. Hamed; L-X. Han; R. Haque; J. W. Harris; S. Heppelmann; A. Hirsch; G. W. Hoffmann; D. J. Hofman; S. Horvat; B. Huang; H. Z. Huang; X. Huang; P. Huck; T. J. Humanic; G. Igo; W. W. Jacobs; H. Jang; E. G. Judd; S. Kabana; D. Kalinkin; K. Kang; K. Kauder; H. W. Ke; D. Keane; A. Kechechyan; A. Kesich; Z. H. Khan; D. P. Kikola; I. Kisel; A. Kisiel; D. D. Koetke; T. Kollegger; J. Konzer; I. Koralt; L. K. Kosarzewski; L. Kotchenda; A. F. Kraishan; P. Kravtsov; K. Krueger; I. Kulakov; L. Kumar; R. A. Kycia; M. A. C. Lamont; J. M. Landgraf; K. D. Landry; J. Lauret; A. Lebedev; R. Lednicky; J. H. Lee; M. J. LeVine; C. Li; W. Li; X. Li; X. Li; Y. Li; Z. M. Li; M. A. Lisa; F. Liu; T. Ljubicic; W. J. Llope; M. Lomnitz; R. S. Longacre; X. Luo; G. L. Ma; Y. G. Ma; D. M. M. D. Madagodagettige Don; D. P. Mahapatra; R. Majka; S. Margetis; C. Markert; H. Masui; H. S. Matis; D. McDonald; T. S. McShane; N. G. Minaev; S. Mioduszewski; B. Mohanty; M. M. Mondal; D. A. Morozov; M. K. Mustafa; B. K. Nandi; Md. Nasim; T. K. Nayak; J. M. Nelson; G. Nigmatkulov; L. V. Nogach; S. Y. Noh; J. Novak; S. B. Nurushev; G. Odyniec; A. Ogawa; K. Oh; A. Ohlson; V. Okorokov; E. W. Oldag; D. L. Olvitt Jr.; M. Pachr; B. S. Page; S. K. Pal; Y. X. Pan; Y. Pandit; Y. Panebratsev; T. Pawlak; B. Pawlik; H. Pei; C. Perkins; W. Peryt; P. Pile; M. Planinic; J. Pluta; N. Poljak; K. Poniatowska; J. Porter; A. M. Poskanzer; N. K. Pruthi; M. Przybycien; P. R. Pujahari; J. Putschke; H. Qiu; A. Quintero; S. Ramachandran; R. Raniwala; S. Raniwala; R. L. Ray; C. K. Riley; H. G. Ritter; J. B. Roberts; O. V. Rogachevskiy; J. L. Romero; J. F. Ross; A. Roy; L. Ruan; J. Rusnak; O. Rusnakova; N. R. Sahoo; P. K. Sahu; I. Sakrejda; S. Salur; J. Sandweiss; E. Sangaline; A. Sarkar; J. Schambach; R. P. Scharenberg; A. M. Schmah; W. B. Schmidke; N. Schmitz; J. Seger; P. Seyboth; N. Shah; E. Shahaliev; P. V. Shanmuganathan; M. Shao; B. Sharma; W. Q. Shen; S. S. Shi; Q. Y. Shou; E. P. Sichtermann; R. N. Singaraju; M. J. Skoby; D. Smirnov; N. Smirnov; D. Solanki; P. Sorensen; H. M. Spinka; B. Srivastava; T. D. S. Stanislaus; J. R. Stevens; R. Stock; M. Strikhanov; B. Stringfellow; M. Sumbera; X. Sun; X. M. Sun; Y. Sun; Z. Sun; B. Surrow; D. N. Svirida; T. J. M. Symons; M. A. Szelezniak; J. Takahashi; A. H. Tang; Z. Tang; T. Tarnowsky; J. H. Thomas; A. R. Timmins; D. Tlusty; M. Tokarev; S. Trentalange; R. E. Tribble; P. Tribedy; B. A. Trzeciak; O. D. Tsai; J. Turnau; T. Ullrich; D. G. Underwood; G. Van Buren; G. van Nieuwenhuizen; M. Vandenbroucke; J. A. Vanfossen, Jr.; R. Varma; G. M. S. Vasconcelos; A. N. Vasiliev; R. Vertesi; F. Videbæk; Y. P. Viyogi; S. Vokal; A. Vossen; M. Wada; F. Wang; G. Wang; H. Wang; J. S. Wang; X. L. Wang; Y. Wang; Y. Wang; G. Webb; J. C. Webb; G. D. Westfall; H. Wieman; S. W. Wissink; R. Witt; Y. F. Wu; Z. Xiao; W. Xie; K. Xin; H. Xu; J. Xu; N. Xu; Q. H. Xu; Y. Xu; Z. Xu; W. Yan; C. Yang; Y. Yang; Y. Yang; Z. Ye; P. Yepes; L. Yi; K. Yip; I-K. Yoo; N. Yu; Y. Zawisza; H. Zbroszczyk; W. Zha; J. B. Zhang; J. L. Zhang; S. Zhang; X. P. Zhang; Y. Zhang; Z. P. Zhang; F. Zhao; J. Zhao; C. Zhong; X. Zhu; Y. H. Zhu; Y. Zoulkarneeva; M. Zyzak

2014-04-05

331

The superconducting magnet for the Maglev transport system  

SciTech Connect

Magnetically levitated vehicles (Maglev) using superconducting magnets have been under development in Japan for the past 23 years. The superconducting magnets for the Maglev system are used in a special environment compared to other applications. They have to work stably subject to both mechanical and electromagnetic disturbances. The brief history of the Maglev development in Japan, the planning of new test line, the superconducting magnet`s stability and the on board refrigeration system will be presented.

Nakashima, Hiroshi [Railway Technical Research Inst., Tokyo (Japan). Maglev System Development Div.] [Railway Technical Research Inst., Tokyo (Japan). Maglev System Development Div.

1994-07-01

332

System for controlling separating gravity in dense-media cyclone  

SciTech Connect

This invention is directed to a method of beneficiating a material, such as coal, by subjecting the coal to be treated to the action of a dense-media cyclone, where the dense-media thereof is a slurry of magnetite in water. More particularly, the present invention relates to a method to control the separating gravity of said cyclone within predetermined limits by measuring the flow rate and percent magnetite in the flow discharging from the cyclone, and based on pre-calibrated data, adjusting the feed flow and content, i.e. magnetite and/or water, into said cyclone, thereby controlling said separating gravity within predetermined limits.

Burgess, C.L.

1984-09-11

333

Magnetic System for the CLAS12 Proposal  

SciTech Connect

The conceptual design of a magnetic system for an experiment to measure the transverse spin effects in semi-inclusive Deep Inelastic Scattering (SIDIS) at 11 GeV with a transversely polarized target using the CLAS12 detector at Jefferson Lab is presented. A proposal has been submitted to study spin azimuthal asymmetries in SIDIS using an 11-GeV polarized electron beam from the upgraded CEBAF facility and the CLAS12 detector equipped with a transversely polarized target. The main focus of the experiment will be the measurement of transverse target single and double spin asymmetries in the reaction ep{up_arrow} -> ehX, where e is an electron, p{up_arrow} is transversely polarized proton, h is a meson (e.g., a pion or a kaon) and X is the undetected final state. The details of the conceptual design of the shielding magnetic system and transverse dipole are reported.

Statera, Marco [INFN, Ferrara (Italy); Contalbrigo, Marco M. [INFN, Ferrara (Italy); Pappalardo, Luciano Libero [INFN, Ferrara (Italy); Barion, Luca [INFN, Ferrara (Italy); Bertelli, S. [INFN, Ferrara (Italy); Ciullo, Giuseppe [INFN, Ferrara (Italy); Lenisa, Paolo [INFN, Ferrara (Italy)

2013-06-01

334

An Experimental Investigation for the Moisture Separation System of a Steam Generator  

Microsoft Academic Search

The Moisture Separation System (MSS) composed of moisture separators and steam dryer banks is the most crucial part of steam generator in terms of the moisture removal performance. Therefore, MSS should be designed very carefully to maximize the moisture removal efficiency. The moisture included in steam-water mixture is primarily removed by the moisture separators in the steam generators of the

Kim Jong-In; Kim Moo-Yong; Bae Hyun-Soo; Lee Byeong-Eun

2006-01-01

335

Nonreciprocal elastic scattering of unpolarized neutrons by magnetic systems with the noncoplanar magnetization distribution  

SciTech Connect

It is shown that the elastic scattering of unpolarized neutrons by systems with the noncoplanar spatial magnetic induction distribution in nonreciprocal. Two systems with the noncoplanar distribution of the magnetic field are proposed and calculated, i.e., a nanoparticle with vortex magnetization and a system of three magnetic mirrors. It is shown that, under certain conditions, the nonreciprocity is rather large and can be observed experimentally.

Tatarskiy, D. A., E-mail: tatarsky@ipmras.ru; Udalov, O. G.; Fraerman, A. A. [Russian Academy of Sciences, Institute for Physics of Microstructures (Russian Federation)

2012-10-15

336

Novel Approach to Linear Accelerator Superconducting Magnet System  

SciTech Connect

Superconducting Linear Accelerators include a superconducting magnet system for particle beam transportation that provides the beam focusing and steering. This system consists of a large number of quadrupole magnets and dipole correctors mounted inside or between cryomodules with SCRF cavities. Each magnet has current leads and powered from its own power supply. The paper proposes a novel approach to magnet powering based on using superconducting persistent current switches. A group of magnets is powered from the same power supply through the common, for the group of cryomodules, electrical bus and pair of current leads. Superconducting switches direct the current to the chosen magnet and close the circuit providing the magnet operation in a persistent current mode. Two persistent current switches were fabricated and tested. In the paper also presented the results of magnetic field simulations, decay time constants analysis, and a way of improving quadrupole magnetic center stability. Such approach substantially reduces the magnet system cost and increases the reliability.

Kashikhin, Vladimir; /Fermilab

2011-11-28

337

Synthesis and performance of novel magnetically separable nanospheres of titanium dioxide photocatalyst with egg-like structure.  

PubMed

A magnetically separable photocatalyst TiO(2)/SiO(2)/NiFe(2)O(4) (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 TiO(2) shell for photocatalysis. The SiO(2) layer between the NiFe(2)O(4) core and the TiO(2) shell effectively prevents the injection of charges from TiO(2) particles to NiFe(2)O(4), which gives rise to an increase in photocatalytic activity. Moreover, the recycled TSN exhibits good repeatability of the photocatalytic activity. PMID:21817681

Xu, Shihong; Shangguan, Wenfeng; Yuan, Jian; Chen, Mingxia; Shi, Jianwei; Jiang, Zhi

2008-03-01

338

Optimization of human corneal endothelial cells for culture: the removal of corneal stromal fibroblast contamination using magnetic cell separation.  

PubMed

The culture of human corneal endothelial cells (CECs) is critical for the development of suitable graft alternative on biodegradable material, specifically for endothelial keratoplasty, which can potentially alleviate the global shortage of transplant-grade donor corneas available. However, the propagation of slow proliferative CECs in vitro can be hindered by rapid growing stromal corneal fibroblasts (CSFs) that may be coisolated in some cases. The purpose of this study was to evaluate a strategy using magnetic cell separation (MACS) technique to deplete the contaminating CSFs from CEC cultures using antifibroblast magnetic microbeads. Separated "labeled" and "flow-through" cell fractions were collected separately, cultured, and morphologically assessed. Cells from the "flow-through" fraction displayed compact polygonal morphology and expressed Na(+)/K(+)ATPase indicative of corneal endothelial cells, whilst cells from the "labeled" fraction were mostly elongated and fibroblastic. A separation efficacy of 96.88% was observed. Hence, MACS technique can be useful in the depletion of contaminating CSFs from within a culture of CECs. PMID:22287967

Peh, Gary S L; Lee, Man-Xin; Wu, Fei-Yi; Toh, Kah-Peng; Balehosur, Deepashree; Mehta, Jodhbir S

2012-01-01

339

Review: Solvent Systems Combining Neutral and Acidic Extractants for Separating Trivalent Lanthanides from the Transuranic Elements  

Microsoft Academic Search

This paper is a review of recent publications that have focused on combined extractant systems for separating trivalent actinides from the lanthanides. These mixed solvent systems combine an acidic extractant with a neutral extractant to achieve the actinide\\/lanthanide separation. Depending on the neutral extractant used, three categorizations of systems can be considered, including combinations of acidic extractants with 1) diamides,

Gregg J. Lumetta; Artem V. Gelis; George F. Vandegrift

2010-01-01

340

Near-surface epigenetic magnetic indicators of buried hydrocarbons and separation of spurious signals  

Microsoft Academic Search

Significant geochemical alteration zones occurring over buried hydrocarbon deposits can be recognized and mapped by geophysical methods. The authors believe near-surface secondary magnetic minerals formed as a result of seeping hydrocarbons and associated compounds interacting with constituents of the overlying rocks. A new method is described to identify anomalous magnetic signatures associated with this mineralization, and to differentiate that signal

T. J. Donovan; D. P. OBrien; J. G. Bryan; M. A. Shepherd

1986-01-01

341

The cyro-thermochromatographic separator (CTS): A new detectionand separation system for highly volatile osmium and hassium (element108) tetroxides  

SciTech Connect

We implemented a new concept for heavy element chemistry research using an ion separator to separate the desired products from the beam, transfer products and other undesirable by-products prior to chemical studies. First, a Recoil product Transfer Chamber (RTC) was designed and attached to the Berkeley Gas-filled Separator (BGS) to collect and transfer the recoiling products to the chemical separation system. The RTC consists of a wire-grid-supported thin mylar foil ({le}) 200 {micro}g/cm{sup 2} that separates the BGS detector chamber, at 1.3 mbar pressure, from the chemistry system at different pressures ranging from 480 mbar to 2000 mbar. The overall transport efficiency ranged between 30% and 15%, compared to the activity measured in the focal plane detector of the BGS. The CTS was designed as a separation and {alpha}-decay detection system for the highly volatile tetroxides of osmium and hassium, element 108. The CTS, shown in figure 1, consists of two rows of 32-{alpha} detectors arranged along a negative temperature gradient. The tetroxides adsorb on the surface of one of the silicone photodiodes at a certain deposition temperature, and the nuclide is then identified by the {alpha}-decay. To test the CTS with the expected hassium homologue osmium, different {alpha}-active osmium isotopes were produced using the nuclear reactions {sup 118}Sn({sup 56}Fe, 4,5n) {sup 170,169}Os and {sup 120}Sn({sup 56}Fe, 4,5n) {sup 172,171}Os. After preseparation in the BGS, a mixture of 90% helium and 10% oxygen was used to transport the osmium to a quartz tube heated to 1225 K, where OsO{sub 4} was formed. The negative temperature gradient in the CTS ranged from 248 K to 173 K. Using a flow rate of 500 mL/min, most of the osmium activity was adsorbed at a temperature of about 203 K. From the measured {alpha}-activity distribution, an adsorption enthalpy of 40 {+-} 1 kJ/mol for OsO{sub 4} on the detector surface was calculated using Monte Carlo simulations. The results show that the CTS is working properly and can be used for experiments studying the chemical properties of hassium.

Kirbach, U.W.; Folden III, C.M.; Ginter, T.N.; Gregorich, K.E.; Lee, D.M.; Ninov, V.; Omtvedt, J.P.; Patin, J.B.; Seward, N.K.; Strellis,D.A.; Sudowe, R.; Wilk, P.A.; Zielinski, P.M.; Hoffman, D.C.; Nitsche, H.

2002-03-08

342

LPV based direct-driven permanent magnet synchronous wind power system controller design  

Microsoft Academic Search

The direct-driven permanent magnet synchronous wind power system has high mechanical oscillation, when the generator is controlled to maximize the efficiency of captured wind energy. To solve these problems, the wind speed is distributed to low frequency and high frequency parts, and it is based on multi-time scale of wind speed and frequency separation principle. The low frequency part of

Xiang-Xia Liu; Yan-Xia Shen; Ting-Long Pan; Hong-Shu Wan

2011-01-01

343

Direct decentralized neural control for nonlinear MIMO magnetic levitation system  

Microsoft Academic Search

A direct modified Elman neural networks (MENNs)-based decentralized controller is proposed to control the magnets of a nonlinear and unstable multi-input multi-output (MIMO) levitation system for the tracking of reference trajectories. First, the operating principles of a magnetic levitation system with two moving magnets are introduced. Then, due to the exact dynamic model of the MIMO magnetic levitation system is

Syuan-yi Chen; Faa-jeng Lin; Kuo-kai Shyu

2009-01-01

344

14 CFR 25.1707 - System separation: EWIS.  

Code of Federal Regulations, 2010 CFR

...CATEGORY AIRPLANES Electrical Wiring Interconnection Systems (EWIS) § 25...necessary to provide electrical connection to the fuel systems components, the...necessary to provide electrical connection to the hydraulic systems components,...

2010-01-01

345

Continuous isotope separation in systems with solid phase. II. Separation of nitrogen isotopes with use of ion-exchange resin  

SciTech Connect

This work deals with the separation of nitrogen isotopes by chemical exchange between ammonia in an aqueous solution and a cation-exchange resin in the NH{sub 4}{sup +} form. Using this system, a continuous process in a simulated moving bed (SMB) is developed. Two operations, the column under total reflux and a continuous feed operation, have been studied. In the latter, the product enriched in heavy nitrogen {sup 15}N was removed from the unit. The operating conditions (2.1-30.5 cm/s superficial liquid velocity, 0.7 mm average resin granules size, and 0.98 N solution of a displacement agent) were close to those used in industrial applications. By studying the separation of nitrogen isotopes, it was shown that displacement ion-exchange chromatography in a practically standard liquid-phase SMB unit provides the opportunity for the flexible production of a number of isotopes of light elements. It was found that flow converting is robust, and the operation and control are simple. It appears that the process design proposed in this work may also be applied for efficiently separating substances other than isotopic mixtures whenever a proper displacement band chromatographic system with nondispersive ends of the band is found.

Kruglov, A.V. [Univ. of Minnesota, Minneapolis, MN (United States); Andreev, B.M.; Pojidaev, Y.E. [Mendeleyev Univ. of Chemical Engineering, Moscow (Russian Federation)

1996-02-01

346

Magnetic Field Experiment Data Analysis System  

NASA Technical Reports Server (NTRS)

The Johns Hopkins University Applied Physics Laboratory (JHU/APL) Magnetic Field Experiment Data Analysis System (MFEDAS) has been developed to process and analyze satellite magnetic field experiment data from the TRIAD, MAGSAT, AMPTE/CCE, Viking, Polar BEAR, DMSP, HILAT, UARS, and Freja satellites. The MFEDAS provides extensive data management and analysis capabilities. The system is based on standard data structures and a standard user interface. The MFEDAS has two major elements: (1) a set of satellite unique telemetry processing programs for uniform and rapid conversion of the raw data to a standard format and (2) the program Magplot which has file handling, data analysis, and data display sections. This system is an example of software reuse, allowing new data sets and software extensions to be added in a cost effective and timely manner. Future additions to the system will include the addition of standard format file import routines, modification of the display routines to use a commercial graphics package based on X-Window protocols, and a generic utility for telemetry data access and conversion.

Holland, D. B.; Zanetti, L. J.; Suther, L. L.; Potemra, T. A.; Anderson, B. J.

1995-01-01

347

Development of a hybrid magnetic resonance and ultrasound imaging system.  

PubMed

A system which allows magnetic resonance (MR) and ultrasound (US) image data to be acquired simultaneously has been developed. B-mode and Doppler US were performed inside the bore of a clinical 1.5 T MRI scanner using a clinical 1-4?MHz US transducer with an 8-metre cable. Susceptibility artefacts and RF noise were introduced into MR images by the US imaging system. RF noise was minimised by using aluminium foil to shield the transducer. A study of MR and B-mode US image signal-to-noise ratio (SNR) as a function of transducer-phantom separation was performed using a gel phantom. This revealed that a 4?cm separation between the phantom surface and the transducer was sufficient to minimise the effect of the susceptibility artefact in MR images. MR-US imaging was demonstrated in vivo with the aid of a 2?mm VeroWhite 3D-printed spherical target placed over the thigh muscle of a rat. The target allowed single-point registration of MR and US images in the axial plane to be performed. The system was subsequently demonstrated as a tool for the targeting and visualisation of high intensity focused ultrasound exposure in the rat thigh muscle. PMID:25177702

Sherwood, Victoria; Civale, John; Rivens, Ian; Collins, David J; Leach, Martin O; ter Haar, Gail R

2014-01-01

348

Development of a Hybrid Magnetic Resonance and Ultrasound Imaging System  

PubMed Central

A system which allows magnetic resonance (MR) and ultrasound (US) image data to be acquired simultaneously has been developed. B-mode and Doppler US were performed inside the bore of a clinical 1.5 T MRI scanner using a clinical 1–4?MHz US transducer with an 8-metre cable. Susceptibility artefacts and RF noise were introduced into MR images by the US imaging system. RF noise was minimised by using aluminium foil to shield the transducer. A study of MR and B-mode US image signal-to-noise ratio (SNR) as a function of transducer-phantom separation was performed using a gel phantom. This revealed that a 4?cm separation between the phantom surface and the transducer was sufficient to minimise the effect of the susceptibility artefact in MR images. MR-US imaging was demonstrated in vivo with the aid of a 2?mm VeroWhite 3D-printed spherical target placed over the thigh muscle of a rat. The target allowed single-point registration of MR and US images in the axial plane to be performed. The system was subsequently demonstrated as a tool for the targeting and visualisation of high intensity focused ultrasound exposure in the rat thigh muscle. PMID:25177702

Sherwood, Victoria; Rivens, Ian; Collins, David J.; Leach, Martin O.; ter Haar, Gail R.

2014-01-01

349

Control of flexible rotor systems with active magnetic bearings  

Microsoft Academic Search

An approach is presented for the analysis and design of magnetic suspension systems with large flexible rotordynamics models including dynamics, control, and simulation. The objective is to formulate and synthesize a large-order, flexible shaft rotordynamics model for a flywheel supported with magnetic bearings. A finite element model of the rotor system is assembled and then employed to develop a magnetic

Shuliang Lei; Alan Palazzolo

2008-01-01

350

Advanced Docking System With Magnetic Initial Capture  

NASA Technical Reports Server (NTRS)

An advanced docking system is undergoing development to enable softer, safer docking than was possible when using prior docking systems. This system is intended for original use in docking of visiting spacecraft and berthing the Crew Return Vehicle at the International Space Station (ISS). The system could also be adapted to a variety of other uses in outer space and on Earth, including mating submersible vehicles, assembling structures, and robotic berthing/handling of payloads and cargo. Heretofore, two large spacecraft have been docked by causing the spacecraft to approach each other at a speed sufficient to activate capture latches - a procedure that results in large docking loads and is made more difficult because of the speed. The basic design and mode of operation of the present advanced docking system would eliminate the need to rely on speed of approach to activate capture latches, thereby making it possible to reduce approach speed and thus docking loads substantially. The system would comprise an active subsystem on one spacecraft and a passive subsystem on another spacecraft with which the active subsystem will be docked. The passive subsystem would include an extensible ring containing magnetic striker plates and guide petals. The active subsystem would include mating guide petals and electromagnets containing limit switches and would be arranged to mate with the magnetic striker plates and guide petals of the passive assembly. The electromagnets would be carried on (but not rigidly attached to) a structural ring that would be instrumented with load sensors. The outputs of the sensors would be sent, along with position information, as feedback to an electronic control subsystem. The system would also include electromechanical actuators that would extend or retract the ring upon command by the control subsystem.

Lewis, James L.; Carroll, Monty B.; Morales, Ray; Le, Thang

2004-01-01

351

Development of superconducting magnet systems for HIFExperiments  

SciTech Connect

The U.S. Heavy Ion Fusion program is developing superconducting focusing quadrupoles for near-term experiments and future driver accelerators. Following the fabrication and testing of several models, a baseline quadrupole design was selected and further optimized. The first prototype of the optimized design achieved a conductor-limited gradient of 132 T/m in a 70 mm bore, with measured field harmonics within 10 parts in 10{sup 4}. In parallel, a compact focusing doublet was fabricated and tested using two of the first-generation quadrupoles. After assembly in the cryostat, both magnets reached their conductor-limited quench current. Further optimization steps are currently underway to improve the performance of the magnet system and reduce its cost. They include the fabrication and testing of a new prototype quadrupole with reduced field errors as well as improvements of the cryostat design for the focusing doublet. The prototype units will be installed in the HCX beamline at LBNL, to perform accelerator physics experiments and gain operational experience. Successful results in the present phase will make superconducting magnets a viable option for the next generation of integrated beam experiments.

Sabbi, Gian Luca; Faltens, A.; Leitzke, A.; Seidl, P.; Lund, S.; Martovets ky, N.; Chiesa, L.; Gung, C.; Minervini, J.; Schultz, J.; Goodzeit, C.; Hwang, P.; Hinson, W.; Meinke, R.

2004-07-27

352

Self-adjusting magnetic bearing systems  

DOEpatents

A self-adjusting magnetic bearing automatically adjusts the parameters of an axially unstable magnetic bearing such that its force balance is maintained near the point of metastable equilibrium. Complete stabilization can be obtained with the application of weak restoring forces either from a mechanical bearing (running at near-zero load, thus with reduced wear) or from the action of residual eddy currents in a snubber bearing. In one embodiment, a torque is generated by the approach of a slotted pole to a conducting plate. The torque actuates an assembly which varies the position of a magnetic shunt to change the force exerted by the bearing. Another embodiment achieves axial stabilization by sensing vertical displacements in a suspended bearing element, and using this information in an electrical servo system. In a third embodiment, as a rotating eddy current exciter approaches a stationary bearing, it heats a thermostat which actuates an assembly to weaken the attractive force between the two bearing elements. An improved version of an electromechanical battery utilizing the designs of the various embodiments is described. 7 figs.

Post, R.F.

1998-07-21

353

Multiple pole electromagnetic propulsion system with separated ballistic guidance and electrical current contact surfaces  

Microsoft Academic Search

An electromagnetic propulsion system is disclosed having separate rails for ballistic guidance and for carrying current. In this system, one or more pairs of ballistic guidance rails are provided, with each ballistic guidance rail having a pair of current carrying rails joined to it to form a combined rail. Each combined rail is separated electrically from adjacent combined rails by

Sims; James R

2008-01-01

354

Method of separating and recovering uranium and related cations from spent Purex-type systems  

DOEpatents

A process for separating uranium and related cations from a spent Purex-type solvent extraction system which contains degradation complexes of tributylphosphate wherein the system is subjected to an ion-exchange process prior to a sodium carbonate scrubbing step. A further embodiment comprises recovery of the separated uranium and related cations. 5 figs.

Mailen, J.C.; Tallent, O.K.

1987-02-25

355

Behavioral/Systems/Cognitive Transcranial Magnetic Stimulation over Posterior Parietal  

E-print Network

Behavioral/Systems/Cognitive Transcranial Magnetic Stimulation over Posterior Parietal Cortex in transsaccadic memory in eight subjects by simultaneously applying single-pulse transcranial magnetic stimulation stimulation coincided more closely with saccade timing. Here, the capacity to compare presaccadic

Crawford, Doug

356

Magnetic tracking system for radiation therapy.  

PubMed

Intensity-modulated radiation therapy (IMRT) requires precise delivery of the prescribed dose of radiation to the target and surrounding tissue. Irradiation of moving body anatomy is possible only if stable, accurate, and reliable information about the moving body structures are provided in real time. This paper presents a magnetic position tracking system for radiation therapy. The proposed system uses only four transmitting coils and an implantable transponder. The four transmitting coils generate a magnetic field which is sensed and measured by a biaxial magnetoresistive sensor in the transponder in the tumor. The transponder transmits the information back to a computer to determine the position of the transponder allowing it to track the tumor in real time. The transmission of the information from the transponder to the computer can be wired or wireless. Measurements using a biaxial sensor agree well with the field strength calculated from the ideal equations. The translation from the measurement data to the 3-D location and orientation requires a numerical technique because the equations are in nonclosed forms. The algorithm of tracking is implemented using MATLAB. Each calculation of the position along the target trajectory takes 30 ms, which makes the proposed system suitable for real-time tracking of the transponder for radiation assessment and delivery. An error of less than 2 mm is achieved in the demonstration. PMID:23853368

Wing-Fai Loke; Tae-Young Choi; Maleki, Teimour; Papiez, Lech; Ziaie, Babak; Byunghoo Jung

2010-08-01

357

A new system of observing and measuring magnetic domain  

NASA Astrophysics Data System (ADS)

A new system of observing and measuring magnetic domain is designed in this paper. The system includes three parts - the principal part of observing and measuring the magnetic domain, the crate controller and the computer used to control the whole system. The principal part consists of x-y scanner, z scanner, digital source meter, ion blower, optical microscope, and giant magnetic resistor (GMR) magnetic head. The GMR magnetic head in this system can be intact after a long-time running in the ordinary laboratory by taking some measures of eliminating electrostatic discharge (ESD). We successfully observed the magnetic domain written in a nanomagnetic material and measured the size of the magnetic domain by use of the new system. The system is very simple and inexpensive, and it has high resolution and signal-to-noise.

Yang, Yongbin; Xu, Wendong

2008-12-01

358

Cardiovascular magnetic resonance in systemic hypertension  

PubMed Central

Systemic hypertension is a highly prevalent potentially modifiable cardiovascular risk factor. Imaging plays an important role in the diagnosis of underlying causes for hypertension, in assessing cardiovascular complications of hypertension, and in understanding the pathophysiology of the disease process. Cardiovascular magnetic resonance (CMR) provides accurate and reproducible measures of ventricular volumes, mass, function and haemodynamics as well as uniquely allowing tissue characterization of diffuse and focal fibrosis. In addition, CMR is well suited for exclusion of common secondary causes for hypertension. We review the current and emerging clinical and research applications of CMR in hypertension. PMID:22559053

2012-01-01

359

5 CFR 293.402 - Establishment of separate employee performance record system.  

Code of Federal Regulations, 2011 CFR

...of separate employee performance record system. 293...OFFICE OF PERSONNEL MANAGEMENT CIVIL SERVICE REGULATIONS...RECORDS Employee Performance File System Records...employees access to their performance files (automated...Office of Personnel Management regulations...

2011-01-01

360

5 CFR 293.402 - Establishment of separate employee performance record system.  

Code of Federal Regulations, 2012 CFR

...of separate employee performance record system. 293...OFFICE OF PERSONNEL MANAGEMENT CIVIL SERVICE REGULATIONS...RECORDS Employee Performance File System Records...employees access to their performance files (automated...Office of Personnel Management regulations...

2012-01-01

361

5 CFR 293.402 - Establishment of separate employee performance record system.  

Code of Federal Regulations, 2013 CFR

...of separate employee performance record system. 293...OFFICE OF PERSONNEL MANAGEMENT CIVIL SERVICE REGULATIONS...RECORDS Employee Performance File System Records...employees access to their performance files (automated...Office of Personnel Management regulations...

2013-01-01

362

Influence of the Propulsion System on the Levitation Characteristics of the HTSC-Permanent Magnet Hybrid Magnetically Levitated System  

Microsoft Academic Search

In the conventional conveyance system, noise, friction and vibration occur under operation. We have developed the hybrid magnetically levitated system. In this system, pinning force of high temperature bulk super conductor is used for the levitation and guidance. This system needs no control system for levitation and guidance. To increase levitation force, repulsive force of the permanent magnet is used.

Shunsuke Ohashi; Daiki Dodo

2007-01-01

363

Magnetic levitation system for moving objects  

Microsoft Academic Search

Repelling magnetic forces are produced by the interaction of a flux-concentrated magnetic field (produced by permanent magnets or electromagnets) with an inductively loaded closed electric circuit. When one such element moves with respect to the other, a current is induced in the circuit. This current then interacts back on the field to produce a repelling force. These repelling magnetic forces

Post; Richard F

1998-01-01

364

Inactivation and magnetic separation of bacteria from liquid suspensions using electrosprayed and nonelectrosprayed nZVI particles: observations and mechanisms.  

PubMed

Here, nonelectrosprayed nanoscale zerovalent iron (NE-nZVI), electrosprayed nZVI (E-nZVI) and preoxidized nZVI (O-nZVI) particles were applied to inactivating Bacillus subtilis, Escherichia coli as well as bacteria in various wastewater samples. In addition, magnetic separation was applied to the mixture of 0.2 mL bacterial sample and 1.8 mL E-nZVI or NE-nZVI suspensions. Bacterial concentrations and optical density of the supernatants were analyzed using culturing, optical adsorption and qPCR tests. In general, for wastewater samples the inactivations were shown to range from 1-log to 3-log. PCR-DGGE analysis indicated that no gene mutation occurred when bacteria were treated with nZVI. Using magnetic separation, significant physical removals, revealed as a function of nZVI type (NE-,E- and O-nZVI) and bacterial concentration, up to 6-log were obtained. E-nZVI and NE-nZVI were shown to react differently with B. subtilis and E. coli, although exhibiting similar inactivation rates. qPCR tests detected higher amount of DNA in the supernatants from mixing E. coli with NE-nZVI, but less for E-nZVI. However, the opposite was observed with B. subtilis. Our data together with optical adsorption analysis suggested that the inactivation and magnetic separation mainly depend on Fe(0)/Fe(3)O(4) shell compositions, the type of bacteria (aerobic and anaerobic) and their concentrations. PMID:22264123

Chen, Qi; Gao, Min; Li, Jing; Shen, Fangxia; Wu, Yan; Xu, Zhenqiang; Yao, Maosheng

2012-02-21

365

Human simulated intelligent control of magnetic levitation systems  

Microsoft Academic Search

The single freedom magnetic levitation ball system is the base of magnetic products, it is essential to study the magnetic levitation ball system. After linearizing and analyzing the nonlinear model of Maglev system, the schema of the human-simulated intelligent control(HSIC) is proposed to deal with the nonlinear and unstable system , moreover the master control algorithms and the parameter self-tuning

Peng Xu; Yuanhong Dan

2010-01-01

366

Experimental microwave system for separation of water-oil emulsions  

Microsoft Academic Search

Description of experimental microwave system for dewatering and demineralization oils is presented. It is based on method of allocation of electromagnetic energy in a duct with dissipative medium by heterogeneous coaxial directive structures. These structures are wide-range and permit actualizing of needful allocation of electromagnetic energy in a duct. The purpose of creating of this system - psychical modeling and

T. A. Ayupov; N. G. Vorobiev

2008-01-01

367

Corridor guided transport system utilizing permanent magnet levitation  

Microsoft Academic Search

The invention relates to a corridor guided transport system including a guided goods conveyance container utilizing permanent magnet levitation. The transport system of the invention eliminates the need for the wheel and track arrangement presently required by known and utilized conventional train systems and also required by some conventional magnetic levitation transport systems and, as a result, is safer to

J. J. Geraghty; A. P. Poland; J. A. Lombardi

1995-01-01

368

Water-compatible magnetic imprinted microspheres for rapid separation and determination of triazine herbicides in environmental water.  

PubMed

A novel kind of water-compatible magnetic imprinted cyromazine microsphere (WCMM) was synthesized by water/oil/water suspension polymerization. The obtained WCMM was homogenously spherical with porous morphology and strong magnetic properties. The microspheres were successfully used as adsorbent in dispersive solid-phase extraction (WCMM-dSPE) to selectively extract cyanazine and atrazine from environmental water. Good linearity of the two analytes was observed in the range from 2.5 to 200.0ngmL(-1). The average recoveries at three spiking levels ranged from 84.8% to 104.3% with relative standard deviations (RSD) less than 6.9%. Compared with magnetic non-imprinted particles (WCMN), the proposed WCMM adsorbent of dSPE efficiently improved the efficiency of extracting cyanazine and atrazine from environmental water samples and eliminated the effect of cyromazine leakage on the quantitative analysis of cyanazine and atrazine. The proposed WCMM-dSPE method combined the advantages of magnetic separation, molecular imprinted microspheres and dSPE. PMID:24657415

Qiao, Fengxia; Row, Kyung Ho; Wang, Mengge

2014-04-15

369

Origin of ferromagnetism and nano-scale phase separations in diluted magnetic semiconductors  

Microsoft Academic Search

This paper reviews various origins of ferromagnetic response that has been detected in diluted magnetic semiconductors (DMS). Particular attention is paid to those ferromagnetic DMS in which no precipitation of other crystallographic phases has been observed. It is argued that these materials can be divided into three categories. The first consists of (Ga,Mn)As and related compounds. In these solid solutions

Tomasz Dietl

2006-01-01

370

A complete digital magnetic resonance imaging (MRI) system at low magnetic field (0.1 Tesla)  

Microsoft Academic Search

A new complete digital MRI system is developed to enhance the signal-to-noise ratio of the detected nuclear magnetic resonance (NMR) signals at low magnetic field (0.1 Tesla). The system is based on digital signal processor (DSP) that functions also as a controller and as an interface between the frequency translator and the digital synthesiser. The final system should be \\

Kosai RAOOF; A. Asfour; J. M. Fournier

2002-01-01

371

Reconstruction algorithms for compressive hyperspectral imaging systems with separable spatial and spectral operators  

NASA Astrophysics Data System (ADS)

Recently we introduced a hyperspectral compressive sensing scheme that uses separable projections in the spatial and spectral domains. The separable encoding schemes facilitates the optical implementation, reduces the computational burden dramatically, and storage requirements. Owing to these benefits we have been able to encode the hyperspectral cube in all three dimensions. In this work we present a comparison between various reconstructions methods applied to the hyperspectral data captured with our separable compressive sensing systems.

Oiknine, Yaniv; August, Yitzhak; Stern, Adrian

2014-09-01

372

Improvement of the Levitation Characteristics in the Magnetic Bearing System Using HTSC-Permanent Magnet Hybrid Structure  

Microsoft Academic Search

Magnetic bearing using pining force of a permanent magnet and a high-temperature superconductor has been developed. Additional permanent magnet is introduced to increase the levitation force of the magnetic bearing. In this hybrid magnetic bearing system, levitation force is mainly given by the repulsive force of the permanent magnets, and stability for the lateral direction is given by pining force

Shunsuke Ohashi

2004-01-01

373

Design and synthesis of reactive separation systems. Final report  

SciTech Connect

During the last decade there has been a rapid upturn in interest in reactive distillation. The chemical process industry recognizes the favorable economics of carrying out reaction simultaneously with distillation for certain classes of reacting systems, and many new processes have been built based on this technology. Interest is also increasing by academics and software vendors. Systematic design methods for reactive distillation systems have only recently begun to emerge. In this report we survey the available design techniques and point out the contributions made by our group at the University of Massachusetts.

Doherty, M.F.

1992-12-31

374

The superconducting magnet for the Maglev transport system  

Microsoft Academic Search

Magnetically levitated vehicles (Maglev) using superconducting magnets have been under development in Japan for the past 23 years. The superconducting magnets for the Maglev system are used in a special environment compared to other applications. They have to work stably subject to both mechanical and electromagnetic disturbances. The brief history of the Maglev development in Japan, the planning of new

Hiroshi Nakashima; Hiroshi

1994-01-01

375

Mechanisms of Magnetic Stimulation of Central Nervous System Neurons  

E-print Network

, Ramat-Gan, Israel Abstract Transcranial magnetic stimulation (TMS) is a stimulation method in which for passively recording neuronal activity, transcranial magnetic stimulation (TMS) actively stimu- lates neuronsMechanisms of Magnetic Stimulation of Central Nervous System Neurons Tamar Pashut1 , Shuki Wolfus2

Bar-Gad, Izhar

376

Is There a Separate Visual Iconic Memory System? Final Report.  

ERIC Educational Resources Information Center

The purpose of these studies was to provide evidence to support either the dual-coding hypothesis or the single-system hypothesis of human memory. In one experiment, college subjects were shown a mixed series of words and pictures either while simultaneously engaged in shadowing (repeating aloud) a prose passage presented via earphones or while…

Levie, W. Howard; Levie, Diane D.

377

Multifunctional superparamagnetic nanoshells: combining two-photon luminescence imaging, surface-enhanced Raman scattering and magnetic separation.  

PubMed

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 (Fe3O4@SiO2@Au), composed of a Fe3O4 cluster core, a thin Au shell and a SiO2 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 Fe3O4@SiO2@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, Fe3O4@SiO2@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

Jin, Xiulong; Li, Haiyan; Wang, Shanshan; Kong, Ni; Xu, Hong; Fu, Qihua; Gu, Hongchen; Ye, Jian

2014-11-01

378

Cell labeling and magnetic separation by means of immunoreagents based on polyacrolein microspheres.  

PubMed

Polyacrolein (PA) microspheres were synthesized by means of ionizing radiation and shown to contain aldehyde groups which form covalent bounds with amino compounds and proteins. PA microspheres made fluorescent after reaction with fluorescein-labeled antibodies were found to specifically label sensitized sheep red blood cells (SRBC). PA microspheres could also be grafted onto a variety of polymeric spheres of different sizes and composition by ionizing radiation. These hybrid spheres, i.e., preformed polymeric spheres with PA microspheres grafted on their surfaces could bind antibodies which retained specificity of reaction with cell surface receptors. Purification of sensitized SRBC from a mixture containing chicken red blood cells (CRBC) by means of hybrids magnetic spheres in a magnetic field was demonstrated. PMID:7130709

Rembaum, A; Yen, R C; Kempner, D H; Ugelstad, J

1982-08-13

379

Tentacle Ion Exchange Separation of Pb-NOM in Aquatic Systems  

E-print Network

exchanger for the separation of metal- organic species in natural freshwaters is investigated using admitted to be dominant, but it has been suggested (3, 4) that natural organic matter (NOM) competesTentacle Ion Exchange Separation of Pb-NOM in Aquatic Systems M . T A I L L E F E R T * A N D J

Taillefert, Martial

380

Modeling and Design of EMI Noise Separators for Multiphase Power Electronics Systems  

Microsoft Academic Search

This paper first discusses the electromagnetic inter- ference (EMI) noise in multiphase power electronics systems using symmetrical component theory and EMI theory. The theory for multiphase noise separators is developed. Multiphase noise sepa- rators are characterized by S-parameters based on symmetrical component theory, S-parameter theory, and EMI theory. A circuit is proposed for multiphase noise separators and techniques are ex-

Shuo Wang

2011-01-01

381

Separation of gas from liquid in a two-phase flow system  

NASA Technical Reports Server (NTRS)

Separation system causes jets which leave two-phase nozzles to impinge on each other, so that liquid from jets tends to coalesce in center of combined jet streams while gas phase is forced to outer periphery. Thus, because liquid coalescence is achieved without resort to separation with solid surfaces, cycle efficiency is improved.

Hayes, L. G.; Elliott, D. G.

1973-01-01

382

Dual-responsive magnetic core-shell nanoparticles for nonviral gene delivery and cell separation.  

PubMed

We present the synthesis of dual-responsive (pH and temperature) magnetic core-shell nanoparticles utilizing the grafting-from approach. First, oleic acid stabilized superparamagnetic maghemite (?-Fe(2)O(3)) nanoparticles (NPs), prepared by thermal decomposition of iron pentacarbonyl, were surface-functionalized with ATRP initiating sites bearing a dopamine anchor group via ligand exchange. Subsequently, 2-(dimethylamino)ethyl methacrylate (DMAEMA) was polymerized from the surface by ATRP, yielding dual-responsive magnetic core-shell NPs (?-Fe(2)O(3)@PDMAEMA). The attachment of the dopamine anchor group on the nanoparticle's surface is shown to be reversible to a certain extent, resulting in a grafting density of 0.15 chains per nm(2) after purification. Nevertheless, the grafted NPs show excellent long-term stability in water over a wide pH range and exhibit a pH- and temperature-dependent reversible agglomeration, as revealed by turbidimetry. The efficiency of ?-Fe(2)O(3)@PDMAEMA hybrid nanoparticles as a potential transfection agent was explored under standard conditions in CHO-K1 cells. Remarkably, ?-Fe(2)O(3)@PDMAEMA led to a 2-fold increase in the transfection efficiency without increasing the cytotoxicity, as compared to polyethyleneimine (PEI), and yielded on average more than 50% transfected cells. Moreover, after transfection with the hybrid nanoparticles, the cells acquired magnetic properties that could be used for selective isolation of transfected cells. PMID:22296556

Majewski, Alexander P; Schallon, Anja; Jérôme, Valérie; Freitag, Ruth; Müller, Axel H E; Schmalz, Holger

2012-03-12

383

Design of an energy storage flywheel system using permanent magnet bearing (PMB) and superconducting magnetic bearing (SMB)  

Microsoft Academic Search

We propose a new energy storage flywheel system using a superconducting magnetic bearing (SMB) and a permanent magnet bearing (PMB). The superconducting magnetic bearing (SMB) suppresses the vibrations of the flywheel rotor. And the permanent magnet bearing (PMB) passively controls the rotor position. The energy storage flywheel system is characterized by using the two different type magnetic bearings of permanent

K. Murakami; M. Komori; H. Mitsuda; A. Inoue

2007-01-01

384

Development of a micro nuclear magnetic resonance system  

Microsoft Academic Search

Application of Nuclear Magnetic Resonance (NMR) to on-line\\/in-line control of industrial processes is currently limited by equipment costs and requirements for installation. A superconducting magnet generating strong fields is the most expensive part of a typical NMR instrument. In industrial environments, fringe magnetic fields make accommodation of NMR instruments difficult. However, a portable, low-cost and low-field magnetic resonance system can

Artem Goloshevsky

2004-01-01

385

Magnetically switched power supply system for lasers  

NASA Technical Reports Server (NTRS)

A laser power supply system is described in which separate pulses are utilized to avalanche ionize the gas within the laser and then produce a sustained discharge to cause the gas to emit light energy. A pulsed voltage source is used to charge a storage device such as a distributed capacitance. A transmission line or other suitable electrical conductor connects the storage device to the laser. A saturable inductor switch is coupled in the transmission line for containing the energy within the storage device until the voltage level across the storage device reaches a predetermined level, which level is less than that required to avalanche ionize the gas. An avalanche ionization pulse generating circuit is coupled to the laser for generating a high voltage pulse of sufficient amplitude to avalanche ionize the laser gas. Once the laser gas is avalanche ionized, the energy within the storage device is discharged through the saturable inductor switch into the laser to provide the sustained discharge. The avalanche ionization generating circuit may include a separate voltage source which is connected across the laser or may be in the form of a voltage multiplier circuit connected between the storage device and the laser.

Pacala, Thomas J. (inventor)

1987-01-01

386

Kapitza problem for the magnetic moments of synthetic antiferromagnetic systems  

SciTech Connect

The dynamics of magnetization in synthetic antiferromagnetic systems with the magnetic dipole coupling in a rapidly oscillating field has been examined. It has been revealed that the system can behave similar to the Kapitza pendulum. It has been shown that an alternating magnetic field can be efficiently used to control the magnetic state of a cell of a synthetic antiferromagnet. Analytical relations have been obtained between the parameters of such an antiferromagnet and an external magnetic field at which certain quasistationary states are implemented.

Dzhezherya, Yu. I. [National Academy of Sciences of Ukraine, Institute of Magnetism (Ukraine); Demishev, K. O., E-mail: demishev.k@gmail.com [National Technical University Kiev Polytechnic Institute (Ukraine); Korenivskii, V. N. [KTH Royal Institute of Technology (Sweden)

2012-08-15

387

Development of Magnetic Pulsed Launcher System using Capacitor Banks  

Microsoft Academic Search

Recent researches on magnetic launcher is rapidly on the rise due to the demand for smooth projectile launching system. A magnetic pulsed launcher (MPL) system is a method for launching a projectile in a smooth linear motion. It applies the basic theories of electromagnetism and circuit theory. This MPL system is basically divided into two categories, one using a coil

M. Rezal; S. J. Iqbal; K. W. Hon

2007-01-01

388

Potential benefits of magnetic suspension and balance systems  

NASA Technical Reports Server (NTRS)

The potential of Magnetic Suspension and Balance Systems (MSBS) to improve conventional wind tunnel testing techniques is discussed. Topics include: elimination of model geometry distortion and support interference to improve the measurement accuracy of aerodynamic coefficients; removal of testing restrictions due to supports; improved dynamic stability data; and stores separation testing. Substantial increases in wind tunnel productivity are anticipated due to the coalescence of these improvements. Specific improvements in testing methods for missiles, helicopters, fighter aircraft, twin fuselage transports and bombers, state separation, water tunnels, and automobiles are also forecast. In a more speculative vein, new wind tunnel test techniques are envisioned as a result of applying MSBS, including free-flight computer trajectories in the test section, pilot-in-the-loop and designer-in-the-loop testing, shipboard missile launch simulation, and optimization of hybrid hypersonic configurations. Also addressed are potential applications of MSBS to such diverse technologies as medical research and practice, industrial robotics, space weaponry, and ore processing in space.

Lawing, Pierce L.; Dress, David A.; Kilgore, Robert A.

1987-01-01

389

The 5.8 T Cryogen-Free Gyrotron Superconducting Magnet System on HL-2A  

NASA Astrophysics Data System (ADS)

A 5.8 T cryogen-free superconducting magnet (SCM) system with a warm bore hole of 160 mm in diameter, used for gyrotrons operating in the frequency range from 68 GHz to 140 GHz, is installed on the site of the HL-2A tokamak. The SCM consists of two separate solenoidal magnetic coils connected in series, a 4.2 K Gifford-McMahon (GM) refrigerator, a compressor, a coil power supply and two temperature monitors. The performance, test and preliminary experimental results of this SCM system are described in this paper. The magnetic field distribution was measured along the axis, and a dummy tube was used for adjusting the magnet system. Finally, the magnet was used for the operation of a 68 GHz/500 kW gyrotron, which is part of an electron cyclotron resonance heating (ECRH) system. With an additional auxiliary coil and after adjusting the magnet system, a maximum output power for the ECRH system of up to 400 kW was achieved.

Xia, Donghui; Huang, Mei; Zhou, Jun; Bai, Xingyu; Zheng, Tieliu; Rao, Jun; Zhuang, Ge

2014-04-01

390

Nuclear magnetic resonance studies of biological systems  

SciTech Connect

The difference between intracellular and extracellular proton relaxation rates provides the basis for the determination of the mean hemoglobin concentration (MHC) in red blood cells. The observed water T{sub 1} relaxation data from red blood cell samples under various conditions were fit to the complete equation for the time-dependent decay of magnetization for a two-compartment system including chemical exchange. The MHC for each sample was calculated from the hematocrit and the intracellular water fraction as determined by NMR. The binding of the phosphorylcholine (PC) analogue, 2-(trimethylphosphonio)-ethylphosphate (phosphoryl-phosphocholine, PPC) to the PC binding myeloma proteins TEPC-15, McPC 603, and MOPC 167 was studied by {sup 31}P NMR.

Antypas, W.G. Jr.

1988-01-01

391

Magnetic bead-based separation of sperm from buccal epithelial cells using a monoclonal antibody against MOSPD3.  

PubMed

Forensic DNA analysis of sexual assault evidence requires unambiguous differentiation of DNA profiles in mixed samples. To investigate the feasibility of magnetic bead-based separation of sperm from cell mixtures using a monoclonal antibody against MOSPD3 (motile sperm domain-containing protein 3), 30 cell samples were prepared by mixing 10(4) female buccal epithelial cells with sperm cells of varying densities (10(3), 10(4), or 10(5) cells/mL). Western blot and immunofluorescence assays showed that MOSPD3 was detectable on the membrane of sperm cells, but not in buccal epithelial cells. After biotinylated MOSPD3 antibody was incubated successively with the prepared cell mixtures and avidin-coated magnetic beads, microscopic observation revealed that each sperm cell was bound by two or more magnetic beads, in the head, neck, mid-piece, or flagellum. A full single-source short tandem repeat profile could be obtained in 80 % of mixed samples containing 10(3) sperm cells/mL and in all samples containing ?10(4) sperm cells/mL. For dried vaginal swab specimens, the rate of successful detection was 100 % in both flocked and cotton swabs preserved for 1 day, 87.5 % in flocked swabs and 40 % in cotton swabs preserved for 3 days, and 40 % in flocked swabs and 16.67 % in cotton swabs preserved for 10 days. Our findings suggest that immunomagnetic bead-based separation is potentially a promising alternative to conventional methods for isolating sperm cells from mixed forensic samples. PMID:24590379

Li, Xue-Bo; Wang, Qing-Shan; Feng, Yu; Ning, Shu-Hua; Miao, Yuan-Ying; Wang, Ye-Quan; Li, Hong-Wei

2014-11-01

392

Superconducting electromagnets for large wind tunnel magnetic suspension and balance systems  

NASA Technical Reports Server (NTRS)

A superconducting electromagnetic suspension and balance system for an 8 x 8-ft, Mach 0.9 wind tunnel is presented. The system uses a superconducting solenoid as a model core 70 cm long and with a 11.5 cm OD, and a combination of permanent magnet material in the model wings to produce the required roll torque. The design, which uses an integral cold structure rather than separate cryostats for mounting all control magnets, has 14 external magnets, including 4 racetrack-shaped roll coils. Helium capacity of the system is 3.0 to 3.5 l with idling boiloff rate predicted at 0.147 to 0.2 l/h. The improvements yielded a 50-percent reduction in the system size, weight, and cost.

Boom, R. W.; Eyssa, Y. M.; Mcintosh, G. E.; Abdelsalam, M. K.; Scurlock, R. G.; Wu, Y. Y.; Goodyer, M. J.; Balcerek, K.; Eskins, J.; Britcher, C. P.

1984-01-01

393

TRITIUM BARRIER MATERIALS AND SEPARATION SYSTEMS FOR THE NGNP  

SciTech Connect

Contamination of downstream hydrogen production plants or other users of high-temperature heat is a concern of the Next Generation Nuclear Plant (NGNP) Project. Due to the high operating temperatures of the NGNP (850-900 C outlet temperature), tritium produced in the nuclear reactor can permeate through heat exchangers to reach the hydrogen production plant, where it can become incorporated into process chemicals or the hydrogen product. The concentration limit for tritium in the hydrogen product has not been established, but it is expected that any future limit on tritium concentration will be no higher than the air and water effluent limits established by the NRC and the EPA. A literature survey of tritium permeation barriers, capture systems, and mitigation measures is presented and technologies are identified that may reduce the movement of tritium to the downstream plant. Among tritium permeation barriers, oxide layers produced in-situ may provide the most suitable barriers, though it may be possible to use aluminized surfaces also. For tritium capture systems, the use of getters is recommended, and high-temperature hydride forming materials such as Ti, Zr, and Y are suggested. Tritium may also be converted to HTO in order to capture it on molecular sieves or getter materials. Counter-flow of hydrogen may reduce the flux of tritium through heat exchangers. Recommendations for research and development work are provided.

Sherman, S; Thad Adams, T

2008-07-17

394

Greek "red mud" residue: a study of microwave reductive roasting followed by magnetic separation for a metallic iron recovery process.  

PubMed

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 Fe?O? ? Fe?O? ? 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. PMID:23611801

Samouhos, Michail; Taxiarchou, Maria; Tsakiridis, Petros E; Potiriadis, Konstantinos

2013-06-15

395

Magnetic separation of heavy metal ions and evaluation based on surface-enhanced Raman spectroscopy: copper(II) ions as a case study.  

PubMed

A new approach was developed for the magnetic separation of copper(II) ions with easy operation and high efficiency. p-Mercaptobenzoic acid served as the modified tag of Fe2O3@Au nanoparticles both for the chelation ligand and Raman reporter. Through the chelation between the copper(II) ions and carboxyl groups on the gold shell, the Fe2O3@Au nanoparticles aggregated to form networks that were enriched and separated from the solution by a magnet. A significant decrease in the concentration of copper(II) ions in the supernatant solution was observed. An extremely sensitive method based on surface-enhanced Raman spectroscopy was employed to detect free copper(II) ions that remained after the magnetic separation, and thus to evaluate the separation efficiency. The results indicated the intensities of the surface-enhanced Raman spectroscopy bands from p-mercaptobenzoic acid were dependent on the concentration of copper(II) ions, and the concentration was decreased by several orders of magnitude after the magnetic separation. The present protocol effectively decreased the total amount of heavy metal ions in the solution. This approach opens a potential application in the magnetic separation and highly sensitive detection of heavy metal ions. PMID:24106161

Yan, Xue; Zhang, Xue-Jiao; Yuan, Ya-Xian; Han, San-Yang; Xu, Min-Min; Gu, Ren'ao; Yao, Jian-Lin

2013-11-01

396

Rotary Drum Separator and Pump for the Sabatier Carbon Dioxide Reduction System  

NASA Technical Reports Server (NTRS)

A trade study conducted in 2001 selected a rotary disk separator as the best candidate to meet the requirements for an International Space Station (ISS) Carbon Dioxide Reduction Assembly (CRA). The selected technology must provide micro-gravity gasfliquid separation and pump the liquid from 10 psia at the gasfliquid interface to 18 psia at the wastewater bus storage tank. The rotary disk concept, which has pedigree in other systems currently being built for installation on the ISS, failed to achieve the required pumping head within the allotted power. The separator discussed in this paper is a new design that was tested to determine compliance with performance requirements in the CRA. The drum separator and pump @SP) design is similar to the Oxygen Generator Assembly (OGA) Rotary Separator Accumulator (RSA) in that it has a rotating assembly inside a stationary housing driven by a integral internal motor. The innovation of the DSP is the drum shaped rotating assembly that acts as the accumulator and also pumps the liquid at much less power than its predecessors. In the CRA application, the separator will rotate at slow speed while accumulating water. Once full, the separator will increase speed to generate sufficient head to pump the water to the wastewater bus. A proof-of- concept (POC) separator has been designed, fabricated and tested to assess the separation efficiency and pumping head of the design. This proof-of-concept item was flown aboard the KC135 to evaluate the effectiveness of the separator in a microgravity environment. This separator design has exceeded all of the performance requirements. The next step in the separator development is to integrate it into the Sabatier Carbon Dioxide Reduction System. This will be done with the Sabatier Engineering Development Unit at the Johnson Space Center.

Holder, Don; Fort, James; Barone, Michael; Murdoch, Karen

2005-01-01

397

Moltox™ Chemical Air Separation System-A Progress Report  

E-print Network

to recent results of the p110t plant test program. Future development needs and plans for commerc1a11zat10n w111 be outlined. INTRODUCTION More than 300,000 TID of large tonnage cryogen1c oxygen plant capac1ty was bu11t 1n the 1960's and 1970's.... The two-th1rds st111 operating w111 consume about $20 b11110n (1985 $) of electr1cal energy 1n the next decade. The HOLTOX m chem1ca1 a1r separat10n system 1s being developed as a cryogen1c oxygen plant replacement wh1ch w111 use energy at less than...

Erickson, D. C.; Brown, W. R.; Dunbobbin, B. R.; Massey, R. G.

398

Concentration influences on recovery in a high gradient magnetic separation axial filter  

SciTech Connect

The buildup differential equations for the case of a single wire in high gradient magnetic filtration (HGMF)-axial configuration taking into account the suspension concentration are solved. A new equation for the deposit contour surface at different moments and for different suspension concentrations are obtained. The existence of a particulate suspension concentration, for which the radial extension velocity of deposit is maximum, is evidenced. The recovery for an ordered ferromagnetic matrix is calculated. The influence of the solid particle concentration from suspension on the filtration efficiency is presented.

Murariu, V.; Rezlescu, N.; Rotariu, O.; Badescu, V. [Inst. of Technical Physics, Iasi (Romania)] [Inst. of Technical Physics, Iasi (Romania)

1998-05-01

399

Magnetic Thin Films for Perpendicular Magnetic Recording Systems  

Microsoft Academic Search

\\u000a In the advanced information society of today, information storage technology, which helps to store a mass of electronic data\\u000a and offers high-speed random access to the data, is indispensable. Against this background, hard disk drives (HDD), which\\u000a are magnetic recording devices, have gained in importance because of their advantages in capacity, speed, reliability, and\\u000a production cost. These days, the uses

Atsushi Sugiyama; Takuma Hachisu; Tetsuya Osaka

2010-01-01

400

Large-gap magnetic positioning system having advantageous configuration  

NASA Technical Reports Server (NTRS)

A magnetic configuration was devised in which the positioned object is maintained in a stable orientation and position on one side of an opaque plane surface entirely by means of magnetic components on the other side of the plane. The system is effective with or without gravity, and can operate in any orientation. In this system, the positioned object need only contain a simple dipole magnet. The positioning components consist of a group of permanent magnets creating a magnetic field configuration which stabilizes the levitated dipole in all but one degree of freedom, and a magnetic position sensing and force feedback system to actively stabilize the object in the one unstable direction. The system utilizes very low power at equilibrium and can maintain gaps of 50 mm.

Chong, Paul; Commandeur, Colin; Davis, Harold; Whitehead, Lorne

1992-01-01

401

Equilibrium values and dynamics of the net magnetic moment of a system of magnetic dipoles  

SciTech Connect

Equilibrium states of different systems formed by coupled spherical bodies with dipole magnetic moments have been investigated using a numerical analysis. The bistable states and the corresponding values of the net magnetic moment are determined for a number of planar and three-dimensional systems of dipoles, and the conditions providing the existence of orientational configurations of coupled dipoles involved in the bistability are analyzed. The disturbances of the magnetic moment due to the quasi-static passage of an additional dipole and the dynamic modes excited by a homogeneous alternating magnetic field and represented by periodic, quasi-periodic, and chaotic oscillations of the magnetic moment of the system are considered for several types of systems. The bifurcation diagrams of the dynamic modes are constructed, and the specific features typical of the systems under consideration are revealed.

Shutyi, A. M., E-mail: shuty@mail.r [Ulyanovsk State University (Russian Federation)

2010-02-15

402

Surveillance and Datalink Communication Performance Analysis for Distributed Separation Assurance System Architectures  

NASA Technical Reports Server (NTRS)

This study investigates the effects of two technical enablers: Automatic Dependent Surveillance - Broadcast (ADS-B) and digital datalink communication, of the Federal Aviation Administration s Next Generation Air Transportation System (NextGen) under two separation assurance (SA) system architectures: ground-based SA and airborne SA, on overall separation assurance performance. Datalink performance such as successful reception probability in both surveillance and communication messages, and surveillance accuracy are examined in various operational conditions. Required SA performance is evaluated as a function of subsystem performance, using availability, continuity, and integrity metrics to establish overall required separation assurance performance, under normal and off-nominal conditions.

Chung, William W.; Linse, Dennis J.; Alaverdi, Omeed; Ifarraguerri, Carlos; Seifert, Scott C.; Salvano, Dan; Calender, Dale

2012-01-01

403

Empirical Magnetic Structure Solution of Frustrated Spin Systems  

NASA Astrophysics Data System (ADS)

Frustrated magnetism plays a central role in the phenomenology of exotic quantum states. However, since the magnetic structures of frustrated systems are often aperiodic, there has been the problem that they cannot be determined by using traditional crystallographic techniques. Here we show that the magnetic component of powder neutron scattering data is actually sufficiently information-rich to drive magnetic structure solution for frustrated systems, including spin ices, spin liquids, and molecular magnets. Our methodology employs ab initio reverse Monte Carlo refinement, making informed use of an additional constraint that minimizes variance in local spin environments. The atomistic spin configurations obtained in this way not only reflect a magnetic structure “solution” but also reproduce the full three-dimensional magnetic scattering pattern.

Paddison, Joseph A. M.; Goodwin, Andrew L.

2012-01-01

404

Power losses in magnetic bearing system for flywheel energy storage  

SciTech Connect

A magnetically suspended flywheel energy storage system has generated unexpected large power losses during spin down tests. Since the system operates in a high vacuum condition, possible power losses come from the hysteresis and eddy current losses of magnetic bearing return rings. To find out their losses, the magnetic properties of the return rings are tested using DC and AC magnetization tests. The results show that the return rings have low AC permeability and huge eddy current loss, which differ greatly from the manufacturer`s specifications. Because of non-laminated magnetic materials, the skin effect of the eddy currents prevents magnetic flux penetration and contributes to higher power loss. A one-dimensional eddy current model is derived and used to confirm the skin effect on the magnetic bearing return rings. In order to eliminate large eddy current loss at high speeds, the usage of thin laminations of high electrical resistance materials is suggested.

Pang, D.C. [Huafan College of Humanities and Technology, Taipei Hsien (Taiwan, Province of China)

1995-12-31

405

Magnetic diagnostic system of the DIII-D tokamak  

NASA Astrophysics Data System (ADS)

External measurements of the magnetic field surrounding a hot, magnetically confined plasma yield important information about the state of the plasma, since the external field is generated in part by electric currents within the plasma itself. Therefore, magnetic diagnostics are an essential part of both the operation and the physics experiments in tokamaks and other magnetic confinement devices. The magnetic diagnostic system of the DIII-D tokamak includes approximately 250 inductive sensors of various types: axisymmetric poloidal flux loops, diamagnetic-flux loops, magnetic probes and saddle loops for the measurement of local magnetic field, and Rogowski loops for the measurement of coil currents and plasma current. The primary uses of the data include plasma shape and position control with a real-time digital control system, postdischarge equilibrium reconstruction, spectrum analysis in time and space of plasma instabilities, and direct feedback control of slowly growing instabilities. The sensors, instrumentation, calibration, applications, and operating experience are described.

Strait, E. J.

2006-02-01

406

Magnetic-marker system using ferrite composite materials  

SciTech Connect

The author`s group has developed some new ferrite composite materials by mixing ferrite by-products with binders such as cement, asphalt cement and epoxy resin. The authors have also developed a magnetic marker sensing system consisting of the ferrite composite material used as a magnetic marker embedded in an asphalt pavement or other surface and a portable magnetic sensor. This system has been applied in a guide lane for the blind and in a speed meter for a motor vehicle.

Mayama, Masakazu [Hokkaido Institute of Technology, Sapporo (Japan)

1993-12-31

407

Corridor guided transport system utilizing permanent magnet levitation  

SciTech Connect

The invention relates to a corridor guided transport system including a guided goods conveyance container utilizing permanent magnet levitation. The transport system of the invention eliminates the need for the wheel and track arrangement presently required by known and utilized conventional train systems and also required by some conventional magnetic levitation transport systems and, as a result, is safer to operate and maintain than either of these known transportation systems.

Geraghty, J.J.; Poland, A.P.; Lombardi, J.A.

1995-07-01

408

Bulk magnetization and 1H NMR spectra of magnetically heterogeneous model systems  

SciTech Connect

Bulk magnetization and {sup 1}H static and magic angle spinning (MAS) nuclear magnetic resonance (NMR) spectra of two magnetically heterogeneous model systems based on laponite (LAP) layered silicate or polystyrene (PS) with low and high proton concentration, respectively, and ferrimagnetic Fe{sub 2}O{sub 3} nano- or micro-particles have been studied. In LAP+Fe{sub 2}O{sub 3}, a major contribution to the NMR signal broadening is due to the dipolar coupling between the magnetic moments of protons and magnetic particles. In PS+Fe{sub 2}O{sub 3}, due to the higher proton concentration in polystyrene and stronger proton–proton dipolar coupling, an additional broadening is observed, i.e. {sup 1}H MAS NMR spectra of magnetically heterogeneous systems are sensitive to both proton–magnetic particles and proton–proton dipolar couplings. An increase of the volume magnetization by ?1 emu/cm{sup 3} affects the {sup 1}H NMR signal width in a way that is similar to an increase of the proton concentration by ?2×10{sup 22}/cm{sup 3}. {sup 1}H MAS NMR spectra, along with bulk magnetization measurements, allow the accurate determination of the hydrogen concentration in magnetically heterogeneous systems.

Levin, E. M.; Bud& #x27; ko, S. L.

2011-04-28

409

Bulk magnetization and 1H NMR spectra of magnetically heterogeneous model systems  

NASA Astrophysics Data System (ADS)

Bulk magnetization and 1H static and magic angle spinning (MAS) nuclear magnetic resonance (NMR) spectra of two magnetically heterogeneous model systems based on laponite (LAP) layered silicate or polystyrene (PS) with low and high proton concentration, respectively, and ferrimagnetic Fe2O3 nano- or micro-particles have been studied. In LAP+Fe2O3, a major contribution to the NMR signal broadening is due to the dipolar coupling between the magnetic moments of protons and magnetic particles. In PS+Fe2O3, due to the higher proton concentration in polystyrene and stronger proton-proton dipolar coupling, an additional broadening is observed, i.e. 1H MAS NMR spectra of magnetically heterogeneous systems are sensitive to both proton-magnetic particles and proton-proton dipolar couplings. An increase of the volume magnetization by ?1 emu/cm3 affects the 1H NMR signal width in a way that is similar to an increase of the proton concentration by ?2×1022/cm3. 1H MAS NMR spectra, along with bulk magnetization measurements, allow the accurate determination of the hydrogen concentration in magnetically heterogeneous systems.

Levin, E. M.; Bud'ko, S. L.

2011-10-01

410

Vanishing Hall Resistance at High Magnetic Field in a Double-Layer Two-Dimensional Electron System  

E-print Network

Vanishing Hall Resistance at High Magnetic Field in a Double-Layer Two-Dimensional Electron System a double-layer two-dimensional electron system with small interlayer separation supports a collective state]. In this Letter we report low-temperature measurements of the Hall and longitudinal resistances of a double-layer

Eisenstein, Jim

411

Simulation and Analysis of Isotope Separation System for Fusion Fuel Recovery System  

NASA Astrophysics Data System (ADS)

This paper presents results of a simulation of the Fuel Recovery System (FRS) for the Laser Inertial Fusion Engine (LIFE) reactor. The LIFE reaction will produce exhaust gases that will need to be recycled in the FRS along with xenon, the chamber's intervention gas. Solids and liquids will first be removed and then vapor traps are used to remove large gas molecules such as lead. The gas will be reacted with lithium at high temperatures to extract the hydrogen isotopes, protium, deuterium, and tritium in hydride form. The hydrogen isotopes will be recovered using a lithium blanket processing system already in place and this product will be sent to the Isotope Separation System (ISS). The ISS will be modeled in software to analyze its effectiveness. Aspen HYSYS was chosen for this purpose for its widespread use industrial gas processing systems. Reactants and corresponding chemical reactions had to be initialized in the software. The ISS primarily consists of four cryogenic distillation columns and these were modeled in HYSYS based on design requirements. Fractional compositions of the distillate and liquid products were analyzed and used to optimize the overall system.

Senevirathna, Bathiya; Gentile, Charles

2011-11-01

412

Local CP-violation and electric charge separation by magnetic fields from lattice QCD  

NASA Astrophysics Data System (ADS)

We study local CP-violation on the lattice by measuring the local correlation between the topological charge density and the electric dipole moment of quarks, induced by a constant external magnetic field. This correlator is found to increase linearly with the external field, with the coefficient of proportionality depending only weakly on temperature. Results are obtained on lattices with various spacings, and are extrapolated to the continuum limit after the renormalization of the observables is carried out. This renormalization utilizes the gradient flow for the quark and gluon fields. Our findings suggest that the strength of local CP-violation in QCD with physical quark masses is about an order of magnitude smaller than a model prediction based on nearly massless quarks in domains of constant gluon backgrounds with topological charge. We also show numerical evidence that the observed local CP-violation correlates with spatially extended electric dipole structures in the QCD vacuum.

Bali, G. S.; Bruckmann, F.; Endr?di, G.; Fodor, Z.; Katz, S. D.; Schäfer, A.

2014-04-01

413

A Magnetic Bumper-Tether System Using ZFC Y123  

NASA Technical Reports Server (NTRS)

We consider the use of magnetic forces in a bumper system, to soften docking procedures. We investigate a system which exhibits no magnetic field except during the docking process, which, if desired, can automatically tether two craft together, and which provides lateral stability during docking. A system composed of zero field cooled Y(1.7)Ba2Cu3O(7-delta) (Y123) tiles and electromagnets is proposed. The Y123 high temperature superconductor (HTS) is mounted on one craft, and the electromagnet on the other. Results of small prototype laboratory experiments are reported. The electromagnet has, for convenience, been replaced by a permanent SmCo ferromagnet in these measurements. When the two craft approach, a mirror image of the ferromagnet is induced in the Y123, and a repulsive bumper force, F(sub B), results. F(sub B) is velocity dependent, and increases with v. For presently available HTS materials, bumper pressure of approx. 3.7 N/cm(exp 2) is achieved using SmCo. This extrapolates to approx. 18 N/cm(exp 2) for an electromagnet, or a force of up to 20 tons for a 1 m(exp 2) system. After reaching a minimum distance of approach, the two colliding craft begin to separate. However, the consequent change of SmCo magnetic field at the Y123 results in a reversal of current in the Y123 so that the Y123 is attractive to the SmCo. The attractive (tether) force, F(sub T), is a function of R = B(sub Fe)/B(sub t, max), where B(sub Fe) is the field at the surface of the ferromagnet, and B(sub t, max) is the maximum trapped field of the Y123, i.e., the trapped field in the so-called critical state. For R greater than or equal to 2, F(sub T) saturates at a value comparable to F(sub B). For a range of initial approach velocities the two craft are tethered following the bumper sequence. Most of the kinetic energy of the collision is first converted to magnetic field energy in the Y123, and then into heat via the creep mechanism. About 15% of the work done against magnetic forces during collision remains stored as magnetic energy after 1 hour. Experiments have also been conducted on the spatial range of the bumper force for arrays of HTS tiles. For a single HTS tile approx. 2 cm in diameter, the range of F(sub B) is approx. l cm. For a l m(exp 2) array the range of F(sub B) will be circa 50 cm.

Weinstein, Roy; Parks, Drew; Sawh, Ravi-Persad; Obot, Victor; Liu, Jianxiong; Arndt, G. D.

1996-01-01

414

System parameters and measurement instrument parameters are not separately observable: Relational mass is observable while absolute mass is not  

E-print Network

A brief summary of the objections to the relational nature of inertial mass, gravitational mass and electric charge is presented. The objections are refuted by showing that the measurement process of comparing an instrument reference clock and a reference rod both obeying the laws of physics to a system obeying the same laws of physics results in relational quantities: inertial mass, gravitational mass and electric charge appear only as ratios. This means that scaling of the absolute inertial mass of every object in the universe by the same factor is unobservable (likewise for gravitational mass and electric charge). It is shown that the measurement process does not separate the instrument parameters from the system parameters. Instead a measurement produces functions of fundamental, dimensionless parameters such as the fine structure constant, electron-proton mass ratio and the proton gyro-magnetic factor. It is shown that the measurement of Planck's constant also results in such a function of these dimensionless parameters. Application of this analysis to the "absolute" Planck units shows that they too are functions only of relational quantities. Analysis focuses initially on non-relativistic systems for the sake of clarity and simplicity. The results are then extended to relativistic systems described by the Dirac equation and the Einstein field equations of general relativity. The results support the assertion that instrument parameters cannot be separated from system parameters even in classical mechanics.

Craig R. Holt

2014-06-19

415

EVIDENCE FOR TWO SEPARATE BUT INTERLACED COMPONENTS OF THE CHROMOSPHERIC MAGNETIC FIELD  

SciTech Connect

Chromospheric fibrils are generally thought to trace out low-lying, mainly horizontal magnetic fields that fan out from flux concentrations in the photosphere. A high-resolution ({approx}0.''1 pixel{sup -1}) image, taken in the core of the Ca II 854.2 nm line and covering an unusually large area, shows the dark fibrils within an active region remnant as fine, looplike features that are aligned parallel to each other and have lengths comparable to a supergranular diameter. Comparison with simultaneous line-of-sight magnetograms confirms that the fibrils are centered above intranetwork areas (supergranular cell interiors), 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 {approx}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 total magnetic flux), 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 links to remote regions of the opposite polarity, forming a second, higher canopy above the fibril canopy. The chromospheric field near the edge of the network thus has an interlaced structure resembling that in sunspot penumbrae.

Reardon, K. P. [Osservatorio Astrofisico di Arcetri, 50125 Firenze (Italy); Wang, Y.-M.; Warren, H. P. [Space Science Division, Naval Research Laboratory, Washington, DC 20375-5352 (United States); Muglach, K., E-mail: kreardon@arcetri.astro.it, E-mail: yi.wang@nrl.navy.mil, E-mail: hwarren@nrl.navy.mil, E-mail: karin.muglach@nasa.gov [NASA Goddard Space Flight Center, Greenbelt, MD 20771 (United States)

2011-12-01

416

Evidence for Two Separate but Interlaced Components of the Chromospheric Magnetic Field  

NASA Technical Reports Server (NTRS)

Chromospheric fibrils are generally thought to trace out low-lying, mainly horizontal magnetic elds that fan out from flux concentrations in the photosphere. A high-resolution (approximately 0.1" per pixel) image, taken in the core of the Ca II 854.2 nm line and covering an unusually large area, shows the dark brils within an active region remnant as fine, looplike features that are aligned parallel to each other and have lengths comparable to a supergranular diameter. Comparison with simultaneous line-of-sight magnetograms confirms that the fibrils are centered above intranetwork areas (supergranular cell interiors), 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 lament channel (large-scale polarity inversion), we find that the total amount of positive-polarity flux underlying this "fibril arcade" is approximately 50 times greater than the total amount of negative-polarity flux. Thus, if the brils represent closed loops, they must consist of very weak fields (in terms of total magnetic flux), 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 links to remote regions of the opposite polarity, forming a second, higher canopy above the fibril canopy. The chromospheric field near the edge of the network thus has an interlaced structure resembling that in sunspot penumbrae.

Reardom, K. P.; Wang, Y.-M.; Muglach, K.; Warren, H. P.

2011-01-01

417

Modelling coils system for generating homogeneous magnetic field  

NASA Astrophysics Data System (ADS)

Magnetometers are used for measuring the characteristics of magnetic field and magnetic properties of the material. A changeable source of a homogeneous magnetic field is necessary for verification and calibration of magnetometers. Often the Helmholtz coil is used for generating magnetic homogeneous field, but homogeneous field area generated by Helmholtz coils is confined to a small volume in the center of the coils. The paper describes result of modeling a coils system to generate a homogeneous magnetic field with increased volume in comparison to Helmholtz coils.

Ogay, V.; Baranov, P.; Stepankova, A.

2014-10-01

418

Applications of magnetic sensors for low cost compass systems  

Microsoft Academic Search

A method for heading determination is described that will include the effects of pitch and roll as well as the magnetic properties of the vehicle. Using solid-state magnetic sensors and a tilt sensor, a low cost compass system can be realized. Commercial airlines today use attitude and heading reference systems that cost tens of thousands of dollars. For general aviation,

Michael J. Caruso

2000-01-01

419

Development of a hybrid-type superconducting magnetic bearing system  

Microsoft Academic Search

To further the practical use of superconducting magnetic bearings (SMBs), a hybrid-type SMB system consisting of SMBs, active magnetic bearings (AMBs) has been developed. The hybrid-type SMB system does not need bias currents applied to the electromagnets for supporting the rotor because the rotor mass is supported by the SMBs. The displacements of the rotor position are suppressed by both

M. Komori; S. Matsuoka; S. Fukata

1996-01-01

420

Improvement of dynamics for a superconducting magnetic bearing (SMB) system  

Microsoft Academic Search

This paper describes the improvement of dynamics for a passive-type superconducting magnetic bearing (SMB) system. The SMB system is composed of a pair of SMBs with high Tc (critical temperature) superconductors and a rotor with some permanent magnets. The rotor is passively supported by the SMBs without any control mechanisms. The superconductors of the SMBs were field-cooled in the experiments.

Mochimitsu Komori; Taku Hamasaki

1998-01-01