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Note: This page contains sample records for the topic "magnetism materials surface" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


1

Nanostructured magnetic materials  

E-Print Network [OSTI]

Magnetism and Magnetic Materials Conference, Atlanta, GA (Nanostructured Magnetic Materials by Keith T. Chan Doctor ofinduced by a Si-based material occurs at a Si/Ni interface

Chan, Keith T.

2011-01-01T23:59:59.000Z

2

Magnetic Materials (MM)  

Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE:1 First Use of Energy for All Purposes (Fuel and Nonfuel),Feet) Year Jan Feb Mar Apr MayAtmospheric Optical Depth7-1D: VegetationEquipment Surfaces and InterfacesAdministration -Lowell L.FallU . S .ofFieldMagnetic Materials

3

MHD problems in free liquid surfaces as plasma-facing materials in magnetically confined reactors  

E-Print Network [OSTI]

-producing magnetically confined reactors. Solid PFC cannot be reliably used because of the large erosion losses during is in 5 T, the density r is g/cm3 , and the liquid metal is lithium. The velocity V0 and thickness/depth h

Harilal, S. S.

4

Large Magnetization at Carbon Surfaces  

Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

Large Magnetization at Carbon Surfaces Large Magnetization at Carbon Surfaces Print Wednesday, 31 August 2011 00:00 From organic matter to pencil lead, carbon is a versatile...

5

Magnetic nanoworms Systematic Surface Engineering of Magnetic Nanoworms  

E-Print Network [OSTI]

Magnetic nanoworms Systematic Surface Engineering of Magnetic Nanoworms for in vivo Tumor Targeting and Engineering Program Department of Chemistry and Biochemistry University of California, San Diego 9500 Gilman magnetic materials nanoworms peptides tumor targeting 694 ß 2009 Wiley-VCH Verlag GmbH & Co. KGa

Bhatia, Sangeeta

6

Magnetic Materials Group  

Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

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7

Magnetic Materials Group - Staff  

Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE:1 First Use of Energy for All Purposes (Fuel and Nonfuel),Feet) Year Jan Feb Mar Apr MayAtmospheric Optical Depth7-1D: VegetationEquipment Surfaces and InterfacesAdministration -Lowell L.FallU . S .ofFieldMagneticFormer

8

Superconductivity and Magnetism: Materials Properties  

E-Print Network [OSTI]

.g. within high-Tc superconductivity, magnetic superconductors, MgB2, CMR materials, nanomagnetism and spin#12;#12;Superconductivity and Magnetism: Materials Properties and Developments #12;Copyright 2003 Risø National Laboratory Roskilde, Denmark ISBN 87-550-3244-3 ISSN 0907-0079 #12;Superconductivity

9

Background Material Important Questions about Magnetism  

E-Print Network [OSTI]

Background Material Important Questions about Magnetism: 1) What is Magnetism?Magnetism is a force or repulsion due to charge is called the electric force. But what about magnetism, is there a fundamental property of some matter that makes things magnetic? The answer is: "sort of." Electric current

Mojzsis, Stephen J.

10

Magnetic Bottles on Riemann Surfaces  

E-Print Network [OSTI]

Yves Colin de Verdiere's quantization formalism of magnetic bottles on Riemann surfaces of non null genus is shown to be affected, owing to the Homotopy Superselection Rule, by the phenomenon of the existence of multiple inequivalent quantizations mathematically analogous to the phenomenon of the existence of multiple inequivalent prequantizations of a multiply-connected symplectic manifold in the framework of Souriau-Kostant's Geometric Quantization.

Gavriel Segre

2011-01-17T23:59:59.000Z

11

Journal of Magnetism and Magnetic Materials ] (  

E-Print Network [OSTI]

magnetic properties were measured with a vibrating sample magnetometer. The mass-specific power loss.40.Rs Keywords: Nanocrystalline alloys; Amorphous alloys; Field annealing; Power loss; Soft magnets the hysteretic power loss while maintaining high-temperature operability [4]. Other goals have included studies

McHenry, Michael E.

12

Magnetic Coordinates for Systems with Imperfect Magnetic Surfaces  

E-Print Network [OSTI]

Magnetic Coordinates for Systems with Imperfect Magnetic Surfaces R. L. Dewar and S. R. Hudson & Engineering, The Australian National University, Canberra, A.C.T. 0200, Australia e-mail: robert-orbits, and the surfaces are formed from a continuous one-parameter family of such orbits. Magnetic field-line flow

Dewar, Robert L.

13

Large Magnetization at Carbon Surfaces  

Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

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14

Large Magnetization at Carbon Surfaces  

Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE:1 First Use of Energy for All Purposes (Fuel and Nonfuel),Feet) Year Jan Feb Mar Apr MayAtmospheric Optical Depth7-1D: VegetationEquipment Surfaces and Interfaces Sample6, 2011 CERN 73-11Large areaLarge Magnetization atLarge

15

Materials Characterization Capabilities at the HTML: Surface...  

Office of Energy Efficiency and Renewable Energy (EERE) Indexed Site

density analysis of forming samples using advanced characterization techniques Materials Characterization Capabilities at the HTML: SurfaceSub-surface dislocation density...

16

Electrically Controllable Surface Magnetism on the Surface of Topological Insulators Jia-Ji Zhu,1  

E-Print Network [OSTI]

Electrically Controllable Surface Magnetism on the Surface of Topological Insulators Jia-Ji Zhu,1 impurities on the surface of three- dimensional topological insulators, mediated by the helical Dirac named topolo- gical insulator (TI) in a number of materials, such as a two-dimensional (2D) HgTe quantum

17

Static magnetic field concentration and enhancement using magnetic materials with positive permeability  

E-Print Network [OSTI]

In this paper a novel compressor for static magnetic fields is proposed based on finite embedded transformation optics. When the DC magnetic field passes through the designed device, the magnetic field can be compressed inside the device. After it passes through the device, one can obtain an enhanced static magnetic field behind the output surface of the device (in a free space region). We can also combine our compressor with some other structures to get a higher static magnetic field enhancement in a free space region. In contrast with other devices based on transformation optics for enhancing static magnetic fields, our device is not a closed structure and thus has some special applications (e.g., for controlling magnetic nano-particles for gene and drag delivery). The designed compressor can be constructed by using currently available materials or DC meta-materials with positive permeability. Numerical simulation verifies good performance of our device.

Sun, F

2013-01-01T23:59:59.000Z

18

Writing magnetic patterns with surface acoustic waves  

SciTech Connect (OSTI)

A novel patterning technique that creates magnetization patterns in a continuous magnetostrictive film with surface acoustic waves is demonstrated. Patterns of 10??m wide stripes of alternating magnetization and a 3??m dot of reversed magnetization are written using standing and focusing acoustic waves, respectively. The magnetization pattern is size-tunable, erasable, and rewritable by changing the magnetic field and acoustic power. This versatility, along with its solid-state implementation (no moving parts) and electronic control, renders it as a promising technique for application in magnetic recording, magnonic signal processing, magnetic particle manipulation, and spatial magneto-optical modulation.

Li, Weiyang; Buford, Benjamin; Jander, Albrecht; Dhagat, Pallavi, E-mail: dhagat@eecs.oregonstate.edu [School of Electrical Engineering and Computer Science, Oregon State University, Corvallis, Oregon 97331 (United States)

2014-05-07T23:59:59.000Z

19

A study of magnetically annealed ferromagnetic materials  

E-Print Network [OSTI]

A STUDY OF MAGNETICALLY ANNEALED FERROMAGNETIC MATERIALS A Thesis By DOMINGO RAMOS Submitted to the Graduate School of the Agricultural and Mechanical College of Texas in partial fulfillment of the requirements for the degree of MASTER... OF SCIENCE August 1961 Major Subject: Electrical Engineering A STUDY OF MAGNETICALLY ANNEALED FERROMAGNETIC MATERIALS A Thesis By 0 ca o o W C DOMINGO RAMOS App ved as to style and content by: r Ct- Chairman of Co ittee Head of Department...

Ramos, Domingo

1961-01-01T23:59:59.000Z

20

Thermal Casimir Force between Magnetic Materials  

E-Print Network [OSTI]

We investigate the Casimir pressure between two parallel plates made of magnetic materials at nonzero temperature. It is shown that for real magnetodielectric materials only the magnetic properties of ferromagnets can influence the Casimir pressure. This influence is accomplished through the contribution of the zero-frequency term of the Lifshitz formula. The possibility of the Casimir repulsion through the vacuum gap is analyzed depending on the model used for the description of the dielectric properties of the metal plates.

G. L. Klimchitskaya; B. Geyer; V. M. Mostepanenko

2009-11-21T23:59:59.000Z

Note: This page contains sample records for the topic "magnetism materials surface" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


21

Journal of Magnetism and Magnetic Materials 252 (2002) 159161 Magnetically induced alignment of FNS  

E-Print Network [OSTI]

Journal of Magnetism and Magnetic Materials 252 (2002) 159­161 Magnetically induced alignment the observation of magnetically controlled anchoring of ferro-nematic suspensions. We found that application of a weak magnetic field to a cell with the ferro-suspension induces an easy orientation axis with weak

Reznikov, Yuri

22

Magnetic spectroscopy and microscopy of functional materials  

SciTech Connect (OSTI)

Heusler intermetallics Mn{sub 2}Y Ga and X{sub 2}MnGa (X; Y =Fe, Co, Ni) undergo tetragonal magnetostructural transitions that can result in half metallicity, magnetic shape memory, or the magnetocaloric effect. Understanding the magnetism and magnetic behavior in functional materials is often the most direct route to being able to optimize current materials for todays applications and to design novel ones for tomorrow. Synchrotron soft x-ray magnetic spectromicroscopy techniques are well suited to explore the the competing effects from the magnetization and the lattice parameters in these materials as they provide detailed element-, valence-, and site-specifc information on the coupling of crystallographic ordering and electronic structure as well as external parameters like temperature and pressure on the bonding and exchange. Fundamental work preparing the model systems of spintronic, multiferroic, and energy-related compositions is presented for context. The methodology of synchrotron spectroscopy is presented and applied to not only magnetic characterization but also of developing a systematic screening method for future examples of materials exhibiting any of the above effects. The chapter progression is as follows: an introduction to the concepts and materials under consideration (Chapter 1); an overview of sample preparation techniques and results, and the kinds of characterization methods employed (Chapter 2); spectro- and microscopic explorations of X{sub 2}MnGa/Ge (Chapter 3); spectroscopic investigations of the composition series Mn{sub 2}Y Ga to the logical Mn{sub 3}Ga endpoint (Chapter 4); and a summary and overview of upcoming work (Chapter 5). Appendices include the results of a Think Tank for the Graduate School of Excellence MAINZ (Appendix A) and details of an imaging project now in progress on magnetic reversal and domain wall observation in the classical Heusler material Co{sub 2}FeSi (Appendix B).

Jenkins, C.A.

2011-01-28T23:59:59.000Z

23

Journal of Magnetism and Magnetic Materials 290291 (2005) 836838 Dynamic response limits of an elastic magnet  

E-Print Network [OSTI]

on the elastomagnetic coupling but also on the interaction among the microparticles magnetic moments depending as for possible applications [1,2]. When the magnetic particles are permanently magnetized and the matrix material. Bar shaped samples have been produced with the permanent magnetic moments preferentially oriented

Franzese, Giancarlo

24

Magnetization and magnetostriction in highly magnetostrictive materials  

SciTech Connect (OSTI)

The majority of this research has been in developing a model to describe the magnetostrictive properties of Terfenol-D, Tb{sub 1{minus}x}Dy{sub x}Fe{sub y} (x = 0.7-0.75 and y = 1.8--2.0), a rare earth-iron alloy which displays much promise for use in device applications. In the first chapter an introduction is given to the phenomena of magnetization and magnetostriction. The magnetic processes responsible for the observed magnetic properties of materials are explained. An overview is presented of the magnetic properties of rare earths, and more specifically the magnetic properties of Terfenol-D. In the second chapter, experimental results are presented on three composition of Tb{sub 1{minus}x}Dy{sub x}Fe{sub y} with x = 0.7, y= 1.9, 1.95, and x= 0.73, y= 1.95. The data were taken for various levels of prestress to show the effects of composition and microstructure on the magnetic and magnetostrictive properties of Terfenol-D. In the third chapter, a theoretical model is developed based on the rotation of magnetic domains. The model is used to explain the magnetic and magnetostrictive properties of Terfenol-D, including the observed negative strictions and large change in strain. The fourth chapter goes on to examine the magnetic properties of Terfenol-D along different crystallographic orientations. In the fifth chapter initial data are presented on the time dependence of magnetization in nickel.

Thoelke, J.B.

1993-05-26T23:59:59.000Z

25

Magnetic mesoporous materials for removal of environmental wastes  

SciTech Connect (OSTI)

We have synthesized two different magnetic mesoporous materials that can be easily separated from aqueous solutions by applying a magnetic field. Synthesized magnetic mesoporous materials, Mag-SBA-15 (magnetic ordered mesoporous silica) and Mag-OMC (magnetic ordered mesoporous carbon), have a high loading capacity of contaminants due to high surface area of the supports and high magnetic activity due to the embedded iron oxide particles. Application of surface-modified Mag-SBA-15 was investigated for the collection of mercury from water. The mercury adsorption using Mag-SBA-15 was rapid during the initial contact time and reached a steady-state condition, with an uptake of approximately 97% after 7 hours. Application of Mag-OMC for collection of organics from water, using fluorescein as an easily trackable model analyte, was explored. The fluorescein was absorbed into Mag-OMC within minutes and the fluorescent intensity of solution was completely disappeared after an hour. In another application, Mag-SBA-15 was used as a host of tyrosinase, and employed as recyclable catalytic scaffolds for tyrosinase-catalyzed biodegradation of catechol. Tyrosinase aggregates in Mag-SBA-15, prepared in a two step process of tyrosinase adsorption and crosslinking, could be used repeatedly for catechol degradation with no serious loss of enzyme activity. Considering these results of cleaning up water from toxic inorganic, organic and biochemical contaminants, magnetic mesoporous materials have a great potential to be employed for the removal of environmental contaminants and potentially for the application in large-scale wastewater treatment plants.

Kim, Byoung Chan; Lee, Jinwoo; Um, Wooyong; Kim, Jaeyun; Joo, Jin; Lee, Jin Hyung; Kwak, Ja Hun; Kim, Jae Hyun; Lee, Changha; Lee, Hongshin; Addleman, Raymond S.; Hyeon, Taeghwan; Gu, Man Bock; Kim, Jungbae

2011-09-15T23:59:59.000Z

26

Large Magnetization at Carbon Surfaces  

Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE:1 First Use of Energy for All Purposes (Fuel and Nonfuel),Feet) Year Jan Feb Mar Apr MayAtmospheric Optical Depth7-1D: VegetationEquipment Surfaces and Interfaces Sample6, 2011 CERN 73-11Large area avalancheLarge

27

Large Magnetization at Carbon Surfaces  

Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE:1 First Use of Energy for All Purposes (Fuel and Nonfuel),Feet) Year Jan Feb Mar Apr MayAtmospheric Optical Depth7-1D: VegetationEquipment Surfaces and Interfaces Sample6, 2011 CERN 73-11Large area avalancheLargeLarge

28

Large Magnetization at Carbon Surfaces  

Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE:1 First Use of Energy for All Purposes (Fuel and Nonfuel),Feet) Year Jan Feb Mar Apr MayAtmospheric Optical Depth7-1D: VegetationEquipment Surfaces and Interfaces Sample6, 2011 CERN 73-11Large area avalancheLargeLargeLarge

29

Large Magnetization at Carbon Surfaces  

Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE:1 First Use of Energy for All Purposes (Fuel and Nonfuel),Feet) Year Jan Feb Mar Apr MayAtmospheric Optical Depth7-1D: VegetationEquipment Surfaces and Interfaces Sample6, 2011 CERN 73-11Large area

30

XPS Analysis of Nanostructured Materials and Biological Surfaces...  

Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

Analysis of Nanostructured Materials and Biological Surfaces. XPS Analysis of Nanostructured Materials and Biological Surfaces. Abstract: This paper examines the types of...

31

Surface treatment of magnetic recording heads  

DOE Patents [OSTI]

Surface modification of magnetic recording heads using plasma immersion ion implantation and deposition is disclosed. This method may be carried out using a vacuum arc deposition system with a metallic or carbon cathode. By operating a plasma gun in a long-pulse mode and biasing the substrate holder with short pulses of a high negative voltage, direct ion implantation, recoil implantation, and surface deposition are combined to modify the near-surface regions of the head or substrate in processing times which may be less than 5 min. The modified regions are atomically mixed into the substrate. This surface modification improves the surface smoothness and hardness and enhances the tribological characteristics under conditions of contact-start-stop and continuous sliding. These results are obtained while maintaining original tolerances. 15 figs.

Komvopoulos, K.; Brown, I.G.; Wei, B.; Anders, S.; Anders, A.; Bhatia, S.C.

1995-12-19T23:59:59.000Z

32

REACT: Alternatives to Critical Materials in Magnets  

SciTech Connect (OSTI)

REACT Project: The 14 projects that comprise ARPA-E’s REACT Project, short for “Rare Earth Alternatives in Critical Technologies”, are developing cost-effective alternatives to rare earths, the naturally occurring minerals with unique magnetic properties that are used in electric vehicle (EV) motors and wind generators. The REACT projects will identify low-cost and abundant replacement materials for rare earths while encouraging existing technologies to use them more efficiently. These alternatives would facilitate the widespread use of EVs and wind power, drastically reducing the amount of greenhouse gases released into the atmosphere.

None

2012-01-01T23:59:59.000Z

33

The Surface Tension of Magnetized Quark Matter  

E-Print Network [OSTI]

The surface tension of quark matter plays a crucial role for the possibility of quark matter nucleation during the formation of compact stellar objects and also for the existence of a mixed phase within hybrid stars. However, despite its importance, this quantity does not have a well established numerical value. Some early estimates have predicted that, at zero temperature, the value falls within the wide range $\\gamma_0\\approx10-300{\\rm\\ MeV/fm^2}$ but, very recently, different model applications have reduced these numerical values to fall within the range $\\gamma_0\\approx5-30{\\rm\\ MeV/fm^2}$ which would favor the phase conversion process as well as the appearance of a mixed phase in hybrid stars. In magnetars one should also account for the presence of very high magnetic fields which may reach up to about $ eB\\approx 3-30\\, m_\\pi^2$ ($B \\approx 10^{19}-10^{20} \\,G$) at the core of the star so that it may also be important to analyze how the presence of a magnetic field affects the surface tension. With this aim we consider magnetized two flavor quark matter, described by the Nambu--Jona-Lasinio model. We show that although the surface tension oscillates around its B=0 value, when $0 surface tension value drops by about 30% while for $eB \\gtrsim 10\\, m_\\pi^2$ it quickly raises with the field intensity so that the phase conversion and the presence of a mixed phase should be suppressed if extremely high fields are present. We also investigate how thermal effects influence the surface tension for magnetized quark matter.

A. F. Garcia; M. B. Pinto

2013-06-13T23:59:59.000Z

34

SURFACE ORBITAL MAGNETISM Herv'e KUNZ \\Lambda  

E-Print Network [OSTI]

SURFACE ORBITAL MAGNETISM Herv'e KUNZ \\Lambda Institut de Physique Th'eorique Ecole Polytechnique F, submitted to a magnetic field. Applying these results to orbital magnetism, we find that at high temperatures or weak magnetic fields the surface magnetisation is always paramag­ netic, but oscillations

35

Magnetic filtration process, magnetic filtering material, and methods of forming magnetic filtering material  

DOE Patents [OSTI]

The present invention provides magnetically responsive activated carbon, and a method of forming magnetically responsive activated carbon. The method of forming magnetically responsive activated carbon typically includes providing activated carbon in a solution containing ions of ferrite forming elements, wherein at least one of the ferrite forming elements has an oxidation state of +3 and at least a second of the ferrite forming elements has an oxidation state of +2, and increasing pH of the solution to precipitate particles of ferrite that bond to the activated carbon, wherein the activated carbon having the ferrite particles bonded thereto have a positive magnetic susceptibility. The present invention also provides a method of filtering waste water using magnetic activated carbon.

Taboada-Serrano, Patricia; Tsouris, Constantino; Contescu, Cristian I; McFarlane, Joanna

2013-10-08T23:59:59.000Z

36

Journal of Magnetism and Magnetic Materials 281 (2004) 272275 Effects of high magnetic field annealing on texture and  

E-Print Network [OSTI]

Journal of Magnetism and Magnetic Materials 281 (2004) 272­275 Effects of high magnetic field annealing on texture and magnetic properties of FePd D.S. Lia, *, H. Garmestania , Shi-shen Yanb , M China c National High Magnetic Field Laboratory, Florida State University, 1800 East Paul Dirac Drive

Garmestani, Hamid

37

Journal of Magnetism and Magnetic Materials 286 (2005) 324328 Light-free magnetic resonance force microscopy for studies of  

E-Print Network [OSTI]

Journal of Magnetism and Magnetic Materials 286 (2005) 324­328 Light-free magnetic resonance force for Physical Sciences, College Park, MD, USA Available online 4 November 2004 Abstract Magnetic resonance force microscopy is a scanned probe technique capable of three-dimensional magnetic resonance imaging. Its

38

Transition-metal silicides as materials for magnet-semiconductor heterostructures*  

E-Print Network [OSTI]

Transition-metal silicides as materials for magnet-semiconductor heterostructures* Peter Kratzer as of binary late transition metal monosilicides, in contact with the Si surface. For the Heusler alloy Co2MnSi, we could show that the 001 surface retains the half-metallic character of the bulk if a fully Mn

39

30-MHz Power Inductor Using Nano-Granular Magnetic Material  

E-Print Network [OSTI]

-granular metal-nonmetal soft magnetic materials con- sist of nano-grains of a magnetic metal in a ceramic matrix [1]­[8]. The ceramic leads to high overall resistivity, while the metal grains are too small of their characteristics are similar to nanocrystalline materials, but the ceramic leads to much higher resistivity

40

Magnetic spectroscopy and microscopy of functional materials  

E-Print Network [OSTI]

in the classical Heusler material Co 2 FeSi (Appendix B).plated self-assembly. Nature Materials, 3:823–828, 2004.1 Concepts Functional materials are those with an industrial

Jenkins, C.A.

2012-01-01T23:59:59.000Z

Note: This page contains sample records for the topic "magnetism materials surface" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


41

MagLab - Magnets and Materials  

Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

needed for everything from magnets for fusion, high energy physics, MRI, to electric power transmission lines and transformers. ASC and MS&T have particularly strong...

42

Magnetic refrigeration apparatus with belt of ferro or paramagnetic material  

DOE Patents [OSTI]

A magnetic refrigerator operating in the 12 to 77 K range utilizes a belt which carries ferromagnetic or paramagnetic material and which is disposed in a loop which passes through the center of a solenoidal magnet to achieve cooling. The magnetic material carried by the belt, which can be blocks in frames of a linked belt, can be a mixture of substances with different Curie temperatures arranged such that the Curie temperatures progressively increase from one edge of the belt to the other. This magnetic refrigerator can be used to cool and liquefy hydrogen or other fluids.

Barclay, J.A.; Stewart, W.F.; Henke, M.D.; Kalash, K.E.

1986-04-03T23:59:59.000Z

43

Magnetic refrigeration apparatus with belt of ferro or paramagnetic material  

DOE Patents [OSTI]

A magnetic refrigerator operating in the 12 to 77K range utilizes a belt which carries ferromagnetic or paramagnetic material and which is disposed in a loop which passes through the center of a solenoidal magnet to achieve cooling. The magnetic material carried by the belt, which can be blocks in frames of a linked belt, can be a mixture of substances with different Curie temperatures arranged such that the Curie temperatures progressively increase from one edge of the belt to the other. This magnetic refrigerator can be used to cool and liquefy hydrogen or other fluids.

Barclay, John A. (Madison, WI); Stewart, Walter F. (Marshall, WI); Henke, Michael D. (Los Alamos, NM); Kalash, Kenneth E. (Los Alamos, NM)

1987-01-01T23:59:59.000Z

44

Ferrofluid surface and volume flows in uniform rotating magnetic fields  

E-Print Network [OSTI]

Ferrofluid surface and volume effects in uniform dc and rotating magnetic fields are studied. Theory and corroborating measurements are presented for meniscus shapes and resulting surface driven flows, spin-up flows, and ...

Elborai, Shihab M. (Shihab Mahmoud), 1977-

2006-01-01T23:59:59.000Z

45

Exploring nanoscale magnetism in advanced materials with polarized X-rays  

E-Print Network [OSTI]

Stoehr and H.C. Siegmann, „Magnetism”, Springer (2006) [93]Exploring nanoscale magnetism in advanced materials withABSTRACT Nanoscale magnetism is of paramount scientific

Fischer, Peter

2012-01-01T23:59:59.000Z

46

Electromagnetic valve for controlling the flow of molten, magnetic material  

DOE Patents [OSTI]

An electromagnetic valve for controlling the flow of molten, magnetic material is provided, which comprises an induction coil for generating a magnetic field in response to an applied alternating electrical current, a housing, and a refractory composite nozzle. The nozzle is comprised of an inner sleeve composed of an erosion resistant refractory material (e.g., a zirconia ceramic) through which molten, magnetic metal flows, a refractory outer shell, and an intermediate compressible refractory material, e.g., unset, high alumina, thermosetting mortar. The compressible refractory material is sandwiched between the inner sleeve and outer shell, and absorbs differential expansion stresses that develop within the nozzle due to extreme thermal gradients. The sandwiched layer of compressible refractory material prevents destructive cracks from developing in the refractory outer shell. 5 figs.

Richter, T.

1998-06-16T23:59:59.000Z

47

Complex curvilinear surfaces in composite materials  

E-Print Network [OSTI]

The thesis will propose a method of architectural design that applies the use of continuous and curvilinear surfaces. It will explore a method of engaging the continuous surface as an expression and response to t he dynamic ...

Liao, Nancy Han, 1975-

2001-01-01T23:59:59.000Z

48

TANK FARM INTERIM SURFACE BARRIER MATERIALS AND RUNOFF ALTERNATIVES STUDY  

SciTech Connect (OSTI)

This report identifies candidate materials and concepts for interim surface barriers in the single-shell tank farms. An analysis of these materials for application to the TY tank farm is also provided.

HOLM MJ

2009-06-25T23:59:59.000Z

49

Digital lock-in detection of site-specific magnetism in magnetic materials  

DOE Patents [OSTI]

The polarization and diffraction characteristics of x-rays incident upon a magnetic material are manipulated to provide a desired magnetic sensitivity in the material. The contrast in diffracted intensity of opposite helicities of circularly polarized x-rays is measured to permit separation of magnetic signals by element type and by atomic environment. This allows for the direct probing of magnetic signals from elements of the same species in nonequivalent atomic environments to better understand the behavior and characteristics of permanent magnetic materials. By using known crystallographic information together with manipulation of the polarization of x-rays having energies tuned near element-specific electronic excitations and by detecting and comparing the incident and diffracted photons at the same frequency, more accurate magnetic measurements can be made over shorter observation periods.

Haskel, Daniel (Naperville, IL); Lang, Jonathan C. (Naperville, IL); Srajer, George (Oak Park, IL)

2008-07-22T23:59:59.000Z

50

Surface electromagnetic wave equations in a warm magnetized quantum plasma  

SciTech Connect (OSTI)

Based on the single-fluid plasma model, a theoretical investigation of surface electromagnetic waves in a warm quantum magnetized inhomogeneous plasma is presented. The surface electromagnetic waves are assumed to propagate on the plane between a vacuum and a warm quantum magnetized plasma. The quantum magnetohydrodynamic model includes quantum diffraction effect (Bohm potential), and quantum statistical pressure is used to derive the new dispersion relation of surface electromagnetic waves. And the general dispersion relation is analyzed in some special cases of interest. It is shown that surface plasma oscillations can be propagated due to quantum effects, and the propagation velocity is enhanced. Furthermore, the external magnetic field has a significant effect on surface wave's dispersion equation. Our work should be of a useful tool for investigating the physical characteristic of surface waves and physical properties of the bounded quantum plasmas.

Li, Chunhua; Yang, Weihong [Department of Modern Physics, University of Science and Technology of China, 230026 Hefei (China); Wu, Zhengwei, E-mail: wuzw@ustc.edu.cn [Department of Modern Physics, University of Science and Technology of China, 230026 Hefei (China); Department of Physics and Materials Science, City University of Hong Kong, Tat Chee Avenue, Kowloon (Hong Kong); Center of Low Temperature Plasma Application, Yunnan Aerospace Industry Company, Kunming, 650229 Yunnan (China); Chu, Paul K. [Department of Physics and Materials Science, City University of Hong Kong, Tat Chee Avenue, Kowloon (Hong Kong)

2014-07-15T23:59:59.000Z

51

Magnetic levitation of metamaterial bodies enhanced with magnetostatic surface resonances  

E-Print Network [OSTI]

We propose that macroscopic objects built from negative-permeability metamaterials may experience resonantly enhanced magnetic force in low-frequency magnetic fields. Resonant enhancement of the time-averaged force originates from magnetostatic surface resonances (MSR) which are analogous to the electrostatic resonances of negative-permittivity particles, well known as surface plasmon resonances in optics. We generalize the classical problem of MSR of a homogeneous object to include anisotropic metamaterials, and consider the most extreme case of anisotropy where the permeability is negative in one direction but positive in the others. It is shown that deeply subwavelength objects made of such indefinite (hyperbolic) media exhibit a pronounced magnetic dipole resonance that couples strongly to uniform or weakly inhomogeneous magnetic field and provides strong enhancement of the magnetic force, enabling applications such as enhanced magnetic levitation.

Urzhumov, Yaroslav; Bingham, Chris; Padilla, Willie; Smith, David R

2011-01-01T23:59:59.000Z

52

Magnetic Filtration Process, Magnetic Filtering Material, and Method of  

Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE:1 First Use of Energy for All Purposes (Fuel and Nonfuel),Feet) Year Jan Feb Mar Apr MayAtmospheric Optical Depth7-1D: VegetationEquipment Surfaces and InterfacesAdministration -Lowell L.FallU . S .ofField Measurements

53

An in situ accelerator-based diagnostic for plasma-material interactions science on magnetic fusion devices  

SciTech Connect (OSTI)

This paper presents a novel particle accelerator-based diagnostic that nondestructively measures the evolution of material surface compositions inside magnetic fusion devices. The diagnostic's purpose is to contribute to an integrated understanding of plasma-material interactions in magnetic fusion, which is severely hindered by a dearth of in situ material surface diagnosis. The diagnostic aims to remotely generate isotopic concentration maps on a plasma shot-to-shot timescale that cover a large fraction of the plasma-facing surface inside of a magnetic fusion device without the need for vacuum breaks or physical access to the material surfaces. Our instrument uses a compact (?1 m), high-current (?1 milliamp) radio-frequency quadrupole accelerator to inject 0.9 MeV deuterons into the Alcator C-Mod tokamak at MIT. We control the tokamak magnetic fields – in between plasma shots – to steer the deuterons to material surfaces where the deuterons cause high-Q nuclear reactions with low-Z isotopes ?5 ?m into the material. The induced neutrons and gamma rays are measured with scintillation detectors; energy spectra analysis provides quantitative reconstruction of surface compositions. An overview of the diagnostic technique, known as accelerator-based in situ materials surveillance (AIMS), and the first AIMS diagnostic on the Alcator C-Mod tokamak is given. Experimental validation is shown to demonstrate that an optimized deuteron beam is injected into the tokamak, that low-Z isotopes such as deuterium and boron can be quantified on the material surfaces, and that magnetic steering provides access to different measurement locations. The first AIMS analysis, which measures the relative change in deuterium at a single surface location at the end of the Alcator C-Mod FY2012 plasma campaign, is also presented.

Hartwig, Zachary S.; Barnard, Harold S.; Lanza, Richard C.; Sorbom, Brandon N.; Stahle, Peter W.; Whyte, Dennis G. [Plasma Science and Fusion Center, Massachusetts Institute of Technology, 77 Massachusetts Ave, Cambridge Massachusetts 02139 (United States)] [Plasma Science and Fusion Center, Massachusetts Institute of Technology, 77 Massachusetts Ave, Cambridge Massachusetts 02139 (United States)

2013-12-15T23:59:59.000Z

54

Materials  

Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

2 MAG LAB REPORTS Volume 18 No. 1 CONDENSED MATTER SCIENCE Technique development, graphene, magnetism & magnetic materials, topological insulators, quantum fl uids & solids,...

55

Materials Characterization Capabilities at the HTML: Surface/Sub-surface  

Office of Energy Efficiency and Renewable Energy (EERE) Indexed Site

AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE: Alternative Fuels Data Center Home Page on Google Bookmark EERE: Alternative Fuels Data Center Home Page on Delicious RankCombustion | Department of EnergyDevelopment Accident TolerantDepartment ofMaterial

56

Thermal stability of MnBi magnetic materials  

SciTech Connect (OSTI)

MnBi has attracted much attention in recent years due to its potential as a rare-earth-free permanent magnet material. It is unique because its coercivity increases with increasing temperature, which makes it a good hard phase material for exchange coupling nanocomposite magnets. MnBi phase is difficult to obtain, partly because the reaction between Mn and Bi is peritectic, and partly because Mn reacts readily with oxygen. MnO formation is irreversible and harmful to magnet performance. In this paper, we report our efforts toward developing MnBi permanent magnets. To date, high purity MnBi (>90%) can be routinely produced in large quantities. The produced powder exhibits 74:6 emu g1 saturation magnetization at room temperature with 9 T applied field. After proper alignment, the maximum energy product (BH) max of the powder reached 11.9 MGOe, and that of the sintered bulk magnet reached 7.8 MGOe at room temperature. A comprehensive study of thermal stability shows that MnBi powder is stable up to 473 K in air.

Cui, Jinfang [Pacific Northwest National Laboratory; Choi, J. P. [Pacific Northwest National Laboratory; Li, G. [Pacific Northwest National Laboratory; Polikarpov, E. [Pacific Northwest National Laboratory; Darsell, J. [Pacific Northwest National Laboratory; Overman, N. [Pacific Northwest National Laboratory; Olszta, M. [Pacific Northwest National Laboratory; Schreiber, D. [Pacific Northwest National Laboratory; Bowden, M. [Environmental Molecular Sciences Laboratory; Droubay, T. [Pacific Northwest National Laboratory; Kramer, Matthew J. [Ames Laboratory; Zarkevich, Nikolay A. [Ames Laboratory; Wang, L L. [Ames Laboratory; Johnson, Duane D. [Ames Laboratory; Marinescu, M. [Electron Energy Corporation; Takeuchi, I. [University of Maryland; Huang, Q. Z. [National Institute of Standards and Technology; Wu, H. [University of Maryland; Reeve, H. [United Technologies Research Center; Vuong, N. V. [University of Texas; Liu, J P. [University of Texas

2014-01-27T23:59:59.000Z

57

Engineered materials for all-optical helicity-dependent magnetic switching  

E-Print Network [OSTI]

Engineered materials for all-optical helicity-dependent magnetic switching S. Mangin1,2 *, M we explore the optical manipulation of the magnetization in engineered magnetic materials. We of engineered magnetic materials and devices. We demonstrate that AO-HDS can be observed not only in selected RE

Fainman, Yeshaiahu

58

Magnetism of individual atoms adsorbed on surfaces Harald Brune a,*, Pietro Gambardella b  

E-Print Network [OSTI]

Magnetism of individual atoms adsorbed on surfaces Harald Brune a,*, Pietro Gambardella b history: Available online 10 February 2009 Keywords: Magnetic impurities Magnetic anisotropy Spin­orbit coupling Dilute magnetic semiconductors Spin excitation spectroscopy Spin-polarized transport Quantized

Brune, Harald

59

Lithium-based surfaces controlling fusion plasma behavior at the plasma-material interface  

SciTech Connect (OSTI)

The plasma-material interface and its impact on the performance of magnetically confined thermonuclear fusion plasmas are considered to be one of the key scientific gaps in the realization of nuclear fusion power. At this interface, high particle and heat flux from the fusion plasma can limit the material's lifetime and reliability and therefore hinder operation of the fusion device. Lithium-based surfaces are now being used in major magnetic confinement fusion devices and have observed profound effects on plasma performance including enhanced confinement, suppression and control of edge localized modes (ELM), lower hydrogen recycling and impurity suppression. The critical spatial scale length of deuterium and helium particle interactions in lithium ranges between 5-100 nm depending on the incident particle energies at the edge and magnetic configuration. Lithium-based surfaces also range from liquid state to solid lithium coatings on a variety of substrates (e.g., graphite, stainless steel, refractory metal W/Mo/etc., or porous metal structures). Temperature-dependent effects from lithium-based surfaces as plasma facing components (PFC) include magnetohydrodynamic (MHD) instability issues related to liquid lithium, surface impurity, and deuterium retention issues, and anomalous physical sputtering increase at temperatures above lithium's melting point. The paper discusses the viability of lithium-based surfaces in future burning-plasma environments such as those found in ITER and DEMO-like fusion reactor devices.

Allain, Jean Paul; Taylor, Chase N. [School of Nuclear Engineering, Purdue University, 400 Central Avenue, West Lafayette, Indiana 47907 (United States)

2012-05-15T23:59:59.000Z

60

Thermal Stability of MnBi Magnetic Materials  

SciTech Connect (OSTI)

MnBi attracts great attention in recent years for its great potential as permanent magnet materials. It is unique because its coercivity increases with increasing temperature, which makes it a good hard phase for exchange coupling nanocomposite magnet. MnBi phase is difficult to obtain, partly because the reaction between Mn and Bi is peritectic, and partly because Mn is easy to react with oxygen. MnO formation is irreversible and causes degradation to the magnetic properties. In this paper, we report our effort on developing MnBi permanent magnet. High purity MnBi (>90%) can be routinely produced in large quantity. The obtained powder exhibit 74 emu/g saturation magnetization at room temperature with 9 T applied field. After alignment, the powder exhibits 11.6 MGOe, and the sintered bulk magnet exhibit 7.8 MGOe at room temperature. Thermal stability study shows that the MnBi is stable up to 473 K in air.

Cui, Jun; Choi, Jung-Pyung; Li, Guosheng; Polikarpov, Evgueni; Darsell, Jens T.; Overman, Nicole R.; Olszta, Matthew J.; Schreiber, Daniel K.; Bowden, Mark E.; Droubay, Timothy C.; Kramer, Matthew J.; Zarkevich, Nikolai; Wang, L. L.; Johnson, Duane D.; Marinescu, Melania; Takeuchi, Ichiro; Huang, Qingzhen; Wu, Hui; Reeve, Hayden; Vuong, Nguyen V.; Liu, J.Ping

2014-01-01T23:59:59.000Z

Note: This page contains sample records for the topic "magnetism materials surface" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


61

Ultra-low field nuclear magnetic resonance and magnetic resonance imaging to discriminate and identify materials  

DOE Patents [OSTI]

An ultra-low magnetic field NMR system can non-invasively examine containers. Database matching techniques can then identify hazardous materials within the containers. Ultra-low field NMR systems are ideal for this purpose because they do not require large powerful magnets and because they can examine materials enclosed in conductive shells such as lead shells. The NMR examination technique can be combined with ultra-low field NMR imaging, where an NMR image is obtained and analyzed to identify target volumes. Spatial sensitivity encoding can also be used to identify target volumes. After the target volumes are identified the NMR measurement technique can be used to identify their contents.

Kraus, Robert H. (Los Alamos, NM); Matlashov, Andrei N. (Los Alamos, NM); Espy, Michelle A. (Los Alamos, NM); Volegov, Petr L. (Los Alamos, NM)

2010-03-30T23:59:59.000Z

62

Surface waves in the magnetized, collisional dusty plasmas  

SciTech Connect (OSTI)

The properties of the low frequency surface waves in inhomogeneous, magnetized collisional complex dusty plasma are investigated in this work. The inhomogeneity is modelled by the two distinct regions of the dusty medium with different dust densities. The external magnetic field is assumed to be oriented along the interface dividing the two medium. It is shown that the collisional momentum exchange that is responsible for the relative drift between the plasma particles affects the propagation of the surface waves in the complex plasma via the Hall drift of the magnetic fluctuations. The propagation properties of the sausage and kink waves depend not only on the grain charge and size distribution but also on the ambient plasma thermal conditions.

Pandey, B. P. [Department of Physics, Astronomy and Research Centre for Astronomy, Astrophysics and Astrophotonics, Macquarie University, Sydney NSW 2109 (Australia)] [Department of Physics, Astronomy and Research Centre for Astronomy, Astrophysics and Astrophotonics, Macquarie University, Sydney NSW 2109 (Australia); Vladimirov, S. V. [School of Physics, The University of Sydney, Sydney NSW 2006 (Australia) [School of Physics, The University of Sydney, Sydney NSW 2006 (Australia); Faculty of Engineering, Yokohama National University, Yokohama 240-8501 (Japan); Metamaterials Laboratory, National Research University of Information Technology, Mechanics, and Optics, St. Petersburg 199034 (Russian Federation); Ishihara, O. [Faculty of Engineering, Yokohama National University, Yokohama 240-8501 (Japan)] [Faculty of Engineering, Yokohama National University, Yokohama 240-8501 (Japan)

2013-10-15T23:59:59.000Z

63

Surface functionalized biocompatible magnetic nanospheres for cancer hyperthermia.  

SciTech Connect (OSTI)

We report a simplified single emulsion (oil-in-water) solvent evaporation protocol to synthesize surface functionalized biocompatible magnetic nanospheres by using highly concentrated hydrophobic magnetite (gel) and a mixture of poly(D,L lactide-co-glycolide) (PLGA) and poly(lactic acid-block-polyethylene glycol-maleimide) (PLA-PEG-maleimide) (10:1 by mass) polymers. The as-synthesized particles are approximately spherical with an average diameter of 360-370 nm with polydispersity index of 0.12-0.18, are surface-functionalized with maleimide groups, and have saturation magnetization values of 25-40 emu/g. The efficiency of the heating induced by 400-kHz oscillating magnetic fields is compared for two samples with different magnetite loadings. Results show that these nanospheres have the potential to provide an efficient cancer-targeted hyperthermia.

Liu, X.; Novosad, V.; Rozhkova, E. A.; Chen, H.; Yefremenko, V.; Pearson, J.; Torno, M.; Bader, S. D.; Rosengart, A. J.; Univ. Chicago Pritzker School of Medicine

2007-06-01T23:59:59.000Z

64

NEUTRON STAR ENVELOPES AND THERMAL RADIATION FROM THE MAGNETIC SURFACE  

E-Print Network [OSTI]

NEUTRON STAR ENVELOPES AND THERMAL RADIATION FROM THE MAGNETIC SURFACE in: C. Kouveliotou, J. van.Petersburg, Russia Abstract. The thermal structure of neutron star envelopes is discussed with emphasis on analytic on the opacities and the thermal structure is further reviewed in view of the application to pulsar cooling

65

Journal of Magnetism and Magnetic Materials 293 (2005) 578583 Theoretical comparison of magnetic and hydrodynamic  

E-Print Network [OSTI]

Ã?, Mikkel Fougt Hansen, Henrik Bruus MIC--Department of Micro and Nanotechnology, Technical University). #12;inhomogeneous magnetic field created by micro- structures that are magnetized by either electro wish to highlight the importance of hydro- dynamic interactions in connection with bead capturing

66

Apparatus for magnetic separation of paramagnetic and diamagnetic material  

DOE Patents [OSTI]

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.

1986-07-24T23:59:59.000Z

67

Apparatus for magnetic separation of paramagnetic and diamagnetic material  

DOE Patents [OSTI]

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.

1988-10-18T23:59:59.000Z

68

Apparatus for magnetic separation of paramagnetic and diamagnetic material  

DOE Patents [OSTI]

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)

1988-01-01T23:59:59.000Z

69

The magnetic resonance force microscope: A new microscopic probe of magnetic materials  

SciTech Connect (OSTI)

The magnetic resonance force microscope (MRFM) marries the techniques of magnetic resonance imaging (MRI) and atomic force microscopy (AFM), to produce a three-dimensional imaging instrument with high, potentially atomic-scale, resolution. The principle of the MRFM has been successfully demonstrated in numerous experiments. By virtue of its unique capabilities the MRFM shows promise to make important contributions in fields ranging from three-dimensional materials characterization to bio-molecular structure determination. Here the authors focus on its application to the characterization and study of layered magnetic materials; the ability to illuminate the properties of buried interfaces in such materials is a particularly important goal. While sensitivity and spatial resolution are currently still far from their theoretical limits, they are nonetheless comparable to or superior to that achievable in conventional MRI. Further improvement of the MRFM will involve operation at lower temperature, application of larger field gradients, introduction of advanced mechanical resonators and improved reduction of the spurious coupling when the magnet is on the resonator.

Hammel, P.C.; Zhang, Z. [Los Alamos National Lab., NM (United States); Midzor, M.; Roukes, M.L. [California Inst. of Tech., Pasadena, CA (United States); Wigen, P.E. [Ohio State Univ., Columbus, OH (United States); Childress, J.R. [Univ. of Florida, Gainesville, FL (United States)

1997-08-06T23:59:59.000Z

70

Titan's Inventory of Organic Surface Materials Ralph D. Lorenz1,*  

E-Print Network [OSTI]

1 Titan's Inventory of Organic Surface Materials Ralph D. Lorenz1,* , Karl L. Mitchell2 , Randolph observations now permit an initial assessment of the inventory of two classes, presumed to be organic, of Titan observed, of which dozens are each estimated to contain more hydrocarbon liquid than the entire known oil

Paris-Sud XI, Université de

71

assisted materials surface: Topics by E-print Network  

Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

assisted materials surface First Page Previous Page 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 Next Page Last Page Topic Index 1 Polymer assisted synthesis...

72

Material Surface Design to Counter Electromagnetic Interrogation of Targets  

E-Print Network [OSTI]

Material Surface Design to Counter Electromagnetic Interrogation of Targets H.T. Banks, K. Ito, G and ferromagnetic layers coat- ing a conducting object to provide an attenuation capability against electro. Fresnel's law for the reflectance index is extended to the electromagnetic propagation in anisotropic

73

Thermal Stability of MnBi Magnetic Materials. | EMSL  

Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE:1 First Use of Energy for All Purposes (Fuel and Nonfuel),Feet) Year Jan Feb Mar Apr MayAtmosphericNuclear SecurityTensile Strain Switched Ferromagnetism in Layered NbS2 andThe1 MembersStability of MnBi Magnetic Materials.

74

Method for large-scale fabrication of atomic-scale structures on material surfaces using surface vacancies  

DOE Patents [OSTI]

A method for forming atomic-scale structures on a surface of a substrate on a large-scale includes creating a predetermined amount of surface vacancies on the surface of the substrate by removing an amount of atoms on the surface of the material corresponding to the predetermined amount of the surface vacancies. Once the surface vacancies have been created, atoms of a desired structure material are deposited on the surface of the substrate to enable the surface vacancies and the atoms of the structure material to interact. The interaction causes the atoms of the structure material to form the atomic-scale structures.

Lim, Chong Wee (Urbana, IL); Ohmori, Kenji (Urbana, IL); Petrov, Ivan Georgiev (Champaign, IL); Greene, Joseph E. (Champaign, IL)

2004-07-13T23:59:59.000Z

75

Impact of fluorine based reactive chemistry on structure and properties of high moment magnetic material  

SciTech Connect (OSTI)

The impact of the fluorine-based reactive ion etch (RIE) process on the structural, electrical, and magnetic properties of NiFe and CoNiFe-plated materials was investigated. Several techniques, including X-ray fluorescence, 4-point-probe, BH looper, transmission electron microscopy (TEM), and electron energy loss spectroscopy (EELS), were utilized to characterize both bulk film properties such as thickness, average composition, Rs, ?, Bs, Ms, and surface magnetic “dead” layers' properties such as thickness and element concentration. Experimental data showed that the majority of Rs and Bs changes of these bulk films were due to thickness reduction during exposure to the RIE process. ? and Ms change after taking thickness reduction into account were negligible. The composition of the bulk films, which were not sensitive to surface magnetic dead layers with nano-meter scale, showed minimum change as well. It was found by TEM and EELS analysis that although both before and after RIE there were magnetic dead layers on the top surface of these materials, the thickness and element concentration of the layers were quite different. Prior to RIE, dead layer was actually native oxidation layers (about 2?nm thick), while after RIE dead layer consisted of two sub-layers that were about 6?nm thick in total. Sub-layer on the top was native oxidation layer, while the bottom layer was RIE “damaged” layer with very high fluorine concentration. Two in-situ RIE approaches were also proposed and tested to remove such damaged sub-layers.

Yang, Xiaoyu, E-mail: xiaoyu.yang@wdc.com; Chen, Lifan; Han, Hongmei; Fu, Lianfeng; Sun, Ming; Liu, Feng; Zhang, Jinqiu [Western Digital Corporation, 44100 Osgood Road, Fremont, California 94539 (United States)

2014-05-07T23:59:59.000Z

76

Use of High Magnetic Field to Control Microstructural Evolution in Metallic and Magnetic Materials  

SciTech Connect (OSTI)

The Amendment 1, referred to as Phase 2, to the original CRADA NFE-06-00414 added tasks 3 through 7 to the original statement of work that had two main tasks that were successfully accomplished in Phase 1 of this project. In this Phase 2 CRADA extension, extensive research and development activities were conducted using high magnetic field processing effects for the purpose of manipulating microstructure in the SAE 5160 steel to refine grain size isothermally and to develop nanocrystalline spacing pearlite during continuous cooling, and to enhance the formability/forgability of the non-ferrous precipitation hardening magnesium alloy AZ90 by applying a high magnetic field during deformation processing to investigate potential magnetoplasticity in this material. Significant experimental issues (especially non-isothermal conditions evolving upon insertion of an isothermal sample in the high magnetic field) were encountered in the isothermal phase transformation reversal experiments (Task 4) that later were determined to be due to various condensed matter physics phenomenon such as the magnetocaloric (MCE) effect that occurs in the vicinity of a materials Curie temperature. Similarly the experimental deformation rig had components for monitoring deformation/strain (Task 3) that were susceptible to the high magnetic field of the ORNL Thermomagnetic Processing facility 9-T superconducting magnet that caused electronic components to fail or record erroneous (very noisy) signals. Limited experiments on developing nanocrystalline spacing pearlite were not sufficient to elucidate the impact of high magnetic field processing on the final pearlite spacing since significant statistical evaluation of many pearlite colonies would need to be done to be conclusive. Since extensive effort was devoted to resolving issues for Tasks 3 and 7, only results for these focused activities are included in this final CRADA report along with those for Task 7 (described in the Objectives Section of this report).

Ludtka, G.M.; Mackiewicz- Ludtka, G.; Wilgen, J.B.; Kisner, R.A.

2010-06-27T23:59:59.000Z

77

Magnetic resonance studies of cement based materials in inhomogeneous magnetic fields  

SciTech Connect (OSTI)

Single-sided magnets give hope that Nuclear Magnetic Resonance (NMR) might in future be used for in situ characterisation of hydration and water transport in the surface layers of concrete slabs. Towards that end, a portable NMR-MOUSE (MObile Universal Surface Explorer) has been used to follow the hydration of gypsum based plaster, a Portland cement paste and concrete mortar. The results compare favourably to those obtained using a standard laboratory bench-top spectrometer. Further, stray field imaging (STRAFI) based methods have been used with embedded NMR detector coils to study water transport across a mortar/topping interface. The measured signal amplitudes are found to correlate with varying sample conditions.

Boguszynska, Joanna [Institute of Molecular Physics, Polish Academy of Sciences, Smoluchowskiego 17, Poznan (Poland); Brown, Marc C.A. [School of Physical Sciences, University of Kent, Canterbury, Kent, CT2 7NR (United Kingdom); McDonald, Peter J. [School of Electronics and Physical Sciences, University of Surrey, Surrey, GU2 7XH (United Kingdom)]. E-mail: p.mcdonald@surrey.ac.uk; Mitchell, Jonathan [School of Electronics and Physical Sciences, University of Surrey, Surrey, GU2 7XH (United Kingdom); Mulheron, Mike [School of Engineering, University of Surrey, Surrey, GU2 7XH (United Kingdom); Tritt-Goc, Jadwiga [Institute of Molecular Physics, Polish Academy of Sciences, Smoluchowskiego 17, Poznan (Poland); Verganelakis, Dimitris A. [Department of Chemical Engineering, University of Cambridge, Cambridge, CB2 3RA (United Kingdom)

2005-10-01T23:59:59.000Z

78

Influence of surface segregation on magnetic properties of FePt nanoparticles  

SciTech Connect (OSTI)

Surface segregation leads to chemical disordering in magnetic alloy nanostructures and thus could have profound impact upon the magnetic properties of these nanostructures. In this study, we used the first-principles density functional theory calculation method to determine how Pt surface segregation (exchanging interior Pt with surface Fe atoms) would affect the magnetic properties of L1{sub 0} ordered FePt nanoparticles. For both cuboid and cuboctahedral FePt nanoparticles, we predicted that the Pt surface segregation process could cause a decrease in total magnetic moments, a change in (easy and/or hard) magnetization axes, and a reduction in magnetic anisotropy.

Lv, Hongyan [Department of Mechanical Engineering and Materials Science, University of Pittsburgh, Pittsburgh, Pennsylvania 15261 (United States) [Department of Mechanical Engineering and Materials Science, University of Pittsburgh, Pittsburgh, Pennsylvania 15261 (United States); Key Laboratory of Artificial Micro- and Nano-Structures of Ministry of Education and School of Physics and Technology, Wuhan University, Wuhan 430072 (China); Lei, Yinkai; Datta, Aditi; Wang, Guofeng [Department of Mechanical Engineering and Materials Science, University of Pittsburgh, Pittsburgh, Pennsylvania 15261 (United States)] [Department of Mechanical Engineering and Materials Science, University of Pittsburgh, Pittsburgh, Pennsylvania 15261 (United States)

2013-09-23T23:59:59.000Z

79

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

DOE Patents [OSTI]

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.

1980-11-06T23:59:59.000Z

80

Selected materials development for the 100 T magnet: Cu-Nb conductors with  

E-Print Network [OSTI]

Selected materials development for the 100 T magnet: Cu-Nb conductors with nanocomposite components (PBO) based composite for reinforcement Materials R&D for the 100-Tesla Pulsed Magnet Gregory S for this achievement was the long-term and painstaking research and development of high strength materials

Weston, Ken

Note: This page contains sample records for the topic "magnetism materials surface" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


81

Correlation Between Domain Behavior and Magnetic Properties of Materials  

SciTech Connect (OSTI)

Correlation between length scales in the field of magnetism has long been a topic of intensive study. The long-term desire is simple: to determine one theory that completely describes the magnetic behavior of matter from an individual atomic particle all the way up to large masses of material. One key piece to this puzzle is connecting the behavior of a material's domains on the nanometer scale with the magnetic properties of an entire large sample or device on the centimeter scale. In the first case study involving the FeSiAl thin films, contrast and spacing of domain patterns are clearly related to microstructure and stress. Case study 2 most clearly demonstrates localized, incoherent domain wall motion switching with field applied along an easy axis for a square hysteresis loop. In case study 3, axis-specific images of the complex Gd-Si-Ge material clearly show the influence of uniaxial anisotropy. Case study 4, the only study with the sole intent of creating domain structures for imaging, also demonstrated in fairly simple terms the effects of increasing stress on domain patterns. In case study 5, it was proven that the width of magnetoresistance loops could be quantitatively predicted using only MFM. When all of the case studies are considered together, a dominating factor seems to be that of anisotropy, both magneticrostaylline and stress induced. Any quantitative bulk measurements heavily reliant on K coefficients, such as the saturation fields for the FeSiAl films, H{sub c} in cases 1, 3, and 5, and the uniaxial character of the Gd{sub 5}(Si{sub 2}Ge{sub 2}), transferred to and from the domain scale quite well. In-situ measurements of domain rotation and switching, could also be strongly correlated with bulk magnetic properties, including coercivity, M{sub s}, and hysteresis loop shape. In most cases, the qualitative nature of the domain structures, when properly considered, matched quite well to what might have been expected from theory and calculation, and provided such information in a matter of minutes. In fact, typical characterization in each of these studies was far more complete and reliable with domain imagery to back it up--especially the single crystal and applied field pictures. In these simple cases, it appears that domain imagery may be close to standing alone in magnetic characterization. The surprises in the 10 nm CoFeHfO film, the complexity seen in the polycrystalline Gd-Si-Ge sample and the broad range predictions of the K{sub 1} of the same reinforce the unreliability of making concrete statements based purely on domain imagery of any type, but it may be possible to create standards similar to the types used in optical microscopy for metallography in these complex cases.

Jeffrey Scott Leib

2003-05-31T23:59:59.000Z

82

Giant Magnetic Effects Induced in Hybrid Materials | U.S. DOE...  

Office of Science (SC) Website

Giant Magnetic Effects Induced in Hybrid Materials Basic Energy Sciences (BES) BES Home About Research Facilities Science Highlights Benefits of BES Funding Opportunities Basic...

83

Comparison of glass surfaces as a countertop material to existing surfaces  

SciTech Connect (OSTI)

Gleen Glass, a small production glass company that creates countertops, was selected for the Technology Assistance Program through Pacific Northwest National Laboratory. Gleen Glass was seeking material property analysis comparing glass as a countertop material to current surfaces (i.e. marble, granite and engineered stone). With samples provided from Gleen Glass, testing was done on granite, marble, and 3 different glass surfaces ('Journey,' 'Pebble,' and 'Gleen'). Results showed the glass surfaces have a lower density, lower water absorption, and are stronger in compressive and flexural tests as compared to granite and marble. Thermal shock tests showed the glass failed when objects with a high thermal mass are placed directly on them, whereas marble and granite did not fracture under these conditions.

Turo, Laura A.; Winschell, Abigail E.

2011-09-01T23:59:59.000Z

84

Surfactant Organic Molecules Restore Magnetism in Metal-Oxide Nanoparticle Surfaces  

E-Print Network [OSTI]

Surfactant Organic Molecules Restore Magnetism in Metal-Oxide Nanoparticle Surfaces Juan Salafranca, Nashville, Tennessee 37235, United States *S Supporting Information ABSTRACT: The properties of magnetic nanoparticles tend to be depressed by the unavoidable presence of a magnetically inactive surface layer. However

Pennycook, Steve

85

Magnetism of Ho and Er Atoms on Close-Packed Metal Surfaces F. Donati,1  

E-Print Network [OSTI]

Magnetism of Ho and Er Atoms on Close-Packed Metal Surfaces F. Donati,1 A. Singha,1 S. Stepanow,2 C; published 3 December 2014) We investigated the magnetic properties of individual Ho atoms adsorbed on the (111) surface of Pt, which have been recently claimed to display single ion magnetic behavior

Thévenaz, Jacques

86

Condensed Surfaces of Magnetic Neutron Stars, Thermal Surface Emission, and Particle Acceleration Above Pulsar Polar Caps  

E-Print Network [OSTI]

For sufficiently strong magnetic fields and/or low temperatures, the neutron star surface may be in a condensed state with little gas or plasma above it. Such surface condensation can significantly affect the thermal emission from isolated neutron stars, and may lead to the formation of a charge-depleted acceleration zone ("vacuum gap") in the magnetosphere above the stellar polar cap. Using the latest results on the cohesive property of magnetic condensed matter, we quantitatively determine the conditions for surface condensation and vacuum gap formation in magnetic neutron stars. We find that condensation can occur if the thermal energy kT of the neutron star surface is less than about 8% of its cohesive energy Q_s, and that a vacuum gap can form if the neutron star's rotation axis and magnetic moment point in opposite directions and kT is less than about 4% of Q_s. Thus, vacuum gap accelerators may exist for some neutron stars. Motivated by this result, we also study the physics of pair cascades in the vacuum gap model for photon emission by accelerating electrons and positrons due to both curvature radiation and resonant/nonresonant inverse Compton scattering. Our calculations of the condition of cascade-induced vacuum breakdown and the related pulsar death line/boundary generalize previous works to the superstrong field regime. We find that inverse Compton scatterings do not produce a sufficient number of high energy photons in the gap and thus do not lead to pair cascades for most neutron star parameters. We discuss the implications of our results for the recent observations of neutron star thermal radiation as well as for the detection/non-detection of radio emission from high-B pulsars and magnetars.

Zach Medin; Dong Lai

2008-01-18T23:59:59.000Z

87

Method for producing high surface area chromia materials for catalysis  

SciTech Connect (OSTI)

Nanostructured chromium(III)-oxide-based materials using sol-gel processing and a synthetic route for producing such materials are disclosed herein. Monolithic aerogels and xerogels having surface areas between 150 m.sup.2/g and 520 m.sup.2/g have been produced. The synthetic method employs the use of stable and inexpensive hydrated-chromium(III) inorganic salts and common solvents such as water, ethanol, methanol, 1-propanol, t-butanol, 2-ethoxy ethanol, and ethylene glycol, DMSO, and dimethyl formamide. The synthesis involves the dissolution of the metal salt in a solvent followed by an addition of a proton scavenger, such as an epoxide, which induces gel formation in a timely manner. Both critical point (supercritical extraction) and atmospheric (low temperature evaporation) drying may be employed to produce monolithic aerogels and xerogels, respectively.

Gash, Alexander E. (Brentwood, CA); Satcher, Joe (Patterson, CA); Tillotson, Thomas (Tracy, CA); Hrubesh, Lawrence (Pleasanton, CA); Simpson, Randall (Livermore, CA)

2007-05-01T23:59:59.000Z

88

RF Surface Impedance Characterization of Potential New Materials for SRF-based Accelerators  

SciTech Connect (OSTI)

In the development of new superconducting materials for possible use in SRF-based accelerators, it is useful to work with small candidate samples rather than complete resonant cavities. The recently commissioned Jefferson Lab RF Surface Impedance Characterization (SIC) system can presently characterize the central region of 50 mm diameter disk samples of various materials from 2 to 40 K exposed to RF magnetic fields up to 14 mT at 7.4 GHz. We report the recent measurement results of bulk Nb, thin film Nb on Cu and sapphire substrates, Nb{sub 3}Sn sample, and thin film MgB{sub 2} on sapphire substrate provided by colleagues at JLab and Temple University.

Xiao, Binping [Thomas Jefferson National Accelerator Facility, Newport News, VA (United States) and College of William and Mary, Williamsburg, VA (United States); Eremeev, Grigory V. [Thomas Jefferson National Accelerator Facility, Newport News, VA (United States); Reece, Charles E. [Thomas Jefferson National Accelerator Facility, Newport News, VA (United States); Phillips, H. Lawrence [Thomas Jefferson National Accelerator Facility, Newport News, VA (United States); Kelley, Michael J. [Thomas Jefferson National Accelerator Facility, Newport News, VA (United States)

2012-09-01T23:59:59.000Z

89

Method of driving liquid flow at or near the free surface using magnetic microparticles  

DOE Patents [OSTI]

The present invention provides a method of driving liquid flow at or near a free surface using self-assembled structures composed of magnetic particles subjected to an external AC magnetic field. A plurality of magnetic particles are supported at or near a free surface of liquid by surface tension or buoyancy force. An AC magnetic field traverses the free surface and dipole-dipole interaction between particles produces in self-assembled snake structures which oscillate at the frequency of the traverse AC magnetic field. The snake structures independently move across the free surface and may merge with other snake structures or break up and coalesce into additional snake structures experiencing independent movement across the liquid surface. During this process, the snake structures produce asymmetric flow vortices across substantially the entirety of the free surface, effectuating liquid flow across the free surface.

Snezhko, Oleksiy (Woodridge, IL); Aronson, Igor (Darien, IL); Kwok, Wai-Kwong (Evanston, IL); Belkin, Maxim V. (Woodridge, IL)

2011-10-11T23:59:59.000Z

90

Magnetic mesoporous material for the sequestration of algae  

DOE Patents [OSTI]

The present invention provides a magnetic mesoporous nanoparticle that includes a mesoporous silicate nanoparticle and iron oxide. The present invention also provides a method of using magnetic mesoporous nanoparticles to sequester microorganisms from a media.

Trewyn, Brian G.; Kandel, Kapil; Slowing, Igor Ivan; Lee, Show-Ling

2014-09-09T23:59:59.000Z

91

A nuclear magnetic resonance study of hydrogen in battery and chemically prepared material  

SciTech Connect (OSTI)

Solid-state magic-angle-spinning nuclear magnetic resonance studies have been undertaken on positive plate material from lead-acid batteries and on samples of both pure ..cap alpha..-PbO/sub 2/ and pure ..beta..-PbO/sub 2/ prepared by nonelectrochemical methods. Battery positive plate samples contain protons in two different surface and near surface configurations. One of these proton species is associated with mobile, isolated, adsorbed hydroxyl groups, and/or water molecules that can be removed by outgassing. The other proton species is not removed by outgassing; it probably corresponds to water molecules and/of closely spaced hydroxyl groups trapped on internal crystal surfaces. The proton species present in fresh (uncycled) positive plate material are not significantly different in either configuration or abundance from those in extensively cycled samples. Thus, it is unlikely that decline in battery capacity with cycling service is associated with a change in the hydrogen content of PbO/sub 2/.

Hill, R.J.; Jessel, A.M.

1987-06-01T23:59:59.000Z

92

Implementation of solar-reflective surfaces: Materials and utility programs  

SciTech Connect (OSTI)

This report focuses on implementation issues for using solar-reflective surfaces to cool urban heat islands, with specific examples for Sacramento, California. Advantages of solar-reflective surfaces for reducing energy use are: (1) they are cost-effective if albedo is increased during routine maintenance; (2) the energy savings coincide with peak demand for power; (3) there are positive effects on environmental quality; and (4) the white materials have a long service life. Important considerations when choosing materials for mitigating heat islands are identified as albedo, emissivity, durability, cost, pollution and appearance. There is a potential for increasing urban albedo in Sacramento by an additional 18%. Of residential roofs, we estimate that asphalt shingle and modified bitumen cover the largest area, and that built-up roofing and modified bitumen cover the largest area of commercial buildings. For all of these roof types, albedo may be increased at the time of re-roofing without any additional cost. When a roof is repaired, a solar-reflective roof coating may be applied to significantly increase albedo and extend the life of the root Although a coating may be cost-effective if applied to a new roof following installation or to an older roof following repair, it is not cost-effective if the coating is applied only to save energy. Solar-reflective pavement may be cost-effective if the albedo change is included in the routine resurfacing schedule. Cost-effective options for producing light-colored pavement may include: (1) asphalt concrete, if white aggregate is locally available; (2) concrete overlays; and (3) newly developed white binders and aggregate. Another option may be hot-rolled asphalt, with white chippings. Utilities could promote solar-reflective surfaces through advertisement, educational programs and cost-sharing of road resurfacing.

Bretz, S.; Akbari, H.; Rosenfeld, A.; Taha, H.

1992-06-01T23:59:59.000Z

93

Magnetic Shape Memory Alloys as smart materials for micro-positioning devices , N. Calchand1  

E-Print Network [OSTI]

Magnetic Shape Memory Alloys as smart materials for micro-positioning devices A. Hubert1 , N reports recent results obtained using a new type of smart material called Magnetic Shape Memory Alloy-mail: arnaud.hubert@femto-st.fr Abstract In the field of microrobotics, actuators based on smart ma- terials

Paris-Sud XI, Université de

94

High frequency transformers and high Q factor inductors formed using epoxy-based magnetic polymer materials  

DOE Patents [OSTI]

An electrical component in the form of an inductor or transformer is disclosed which includes one or more coils and a magnetic polymer material located near the coils or supporting the coils to provide an electromagnetic interaction therewith. The magnetic polymer material is preferably a cured magnetic epoxy which includes a mercaptan derivative having a ferromagnetic atom chemically bonded therein. The ferromagnetic atom can be either a transition metal or rare-earth atom.

Sanchez, Robert O. (Los Lunas, NM); Gunewardena, Shelton (Walnut, CA); Masi, James V. (Cape Elizabeth, ME)

2007-11-27T23:59:59.000Z

95

Iron-Nickel-Based SuperMagnets: Multiscale Development of L10 Materials for Rare Earth-Free Permanent Magnets  

SciTech Connect (OSTI)

REACT Project: Northeastern University will develop bulk quantities of rare-earth-free permanent magnets with an iron-nickel crystal structure for use in the electric motors of renewable power generators and EVs. These materials could offer magnetic properties that are equivalent to today’s best commercial magnets, but with a significant cost reduction and diminished environmental impact. This iron-nickel crystal structure, which is only found naturally in meteorites and developed over billions of years in space, will be artificially synthesized by the Northeastern University team. Its material structure will be replicated with the assistance of alloying elements introduced to help it achieve superior magnetic properties. The ultimate goal of this project is to demonstrate bulk magnetic properties that can be fabricated at the industrial scale.

None

2012-01-01T23:59:59.000Z

96

Fourth annual progress report on special-purpose materials for magnetically confined fusion reactors  

SciTech Connect (OSTI)

The scope of Special Purpose Materials covers fusion reactor materials problems other than the first-wall and blanket structural materials, which are under the purview of the ADIP, DAFS, and PMI task groups. Components that are considered as special purpose materials include breeding materials, coolants, neutron multipliers, barriers for tritium control, materials for compression and OH coils and waveguides, graphite and SiC, heat-sink materials, ceramics, and materials for high-field (>10-T) superconducting magnets. The Task Group on Special Purpose Materials has limited its concern to crucial and generic materials problems that must be resolved if magnetic-fusion devices are to succeed. Important areas specifically excluded include low-field (8-T) superconductors, fuels for hybrids, and materials for inertial-confinement devices. These areas may be added in the future when funding permits.

Not Available

1982-08-01T23:59:59.000Z

97

Hamilton flow generated by field lines near a toroidal magnetic surface  

SciTech Connect (OSTI)

A method is described for obtaining the Hamiltonian of a vacuum magnetic field in a given 3D toroidal magnetic surface (superconducting shell). This method is used to derive the expression for the integrable surface Hamiltonian in the form of the expansion of a rotational transform of field lines on embedded near-boundary magnetic surfaces into a Taylor series in the distance from the boundary. This expansion contains the value of the rotational transform and its shear at the boundary surface. It is shown that these quantities are related to the components of the first and second quadratic forms of the boundary surface.

Skovoroda, A. A., E-mail: skovorod@nfi.kiae.ru [National Research Center Kurchatov Institute (Russian Federation)

2013-07-15T23:59:59.000Z

98

Characterizing artificial electromagnetic materials and their hybridization with fundamentally resonant magnetic materials  

E-Print Network [OSTI]

4 Ferromagnetic Materials in Microstrip Structures . . . 4.1Ferromagnetic Materials . . . . . . . . . . . . . . 4.3 The1: positive material 1 , µ 1 > 0 . . . . . . . . . . . . . .

Gollub, Jonah Nathan

2008-01-01T23:59:59.000Z

99

Final Scientific/Technical Report for DOE/EERE project Advanced Magnetic Refrigerant Materials  

SciTech Connect (OSTI)

A team led by GE Global Research developed new magnetic refrigerant materials needed to enhance the commercialization potential of residential appliances such as refrigerators and air conditioners based on the magnetocaloric effect (a nonvapor compression cooling cycle). The new magnetic refrigerant materials have potentially better performance at lower cost than existing materials, increasing technology readiness level. The performance target of the new magnetocaloric material was to reduce the magnetic field needed to achieve 4 °C adiabatic temperature change from 1.5 Tesla to 0.75 Tesla. Such a reduction in field minimizes the cost of the magnet assembly needed for a magnetic refrigerator. Such a reduction in magnet assembly cost is crucial to achieving commercialization of magnetic refrigerator technology. This project was organized as an iterative alloy development effort with a parallel material modeling task being performed at George Washington University. Four families of novel magnetocaloric alloys were identified, screened, and assessed for their performance potential in a magnetic refrigeration cycle. Compositions from three of the alloy families were manufactured into regenerator components. At the beginning of the project a previously studied magnetocaloric alloy was selected for manufacturing into the first regenerator component. Each of the regenerators was tested in magnetic refrigerator prototypes at a subcontractor at at GE Appliances. The property targets for operating temperature range, operating temperature control, magnetic field sensitivity, and corrosion resistance were met. The targets for adiabatic temperature change and thermal hysteresis were not met. The high thermal hysteresis also prevented the regenerator components from displaying measurable cooling power when tested in prototype magnetic refrigerators. Magnetic refrigerant alloy compositions that were predicted to have low hysteresis were not attainable with conventional alloy processing methods. Preliminary experiments with rapid solidification methods showed a path towards attaining low hysteresis compositions should this alloy development effort be continued.

Johnson, Francis

2014-06-30T23:59:59.000Z

100

3D MHD Free Surface Fluid Flow Simulation Based on Magnetic-Field Induction Equations  

E-Print Network [OSTI]

1 3D MHD Free Surface Fluid Flow Simulation Based on Magnetic-Field Induction Equations H.L. HUANG Huang@fusion.ucla.edu Abstract: The purpose of this paper is to present our recent efforts on 3D MHD-plane magnetic field configurations have shown that 3D MHD effects from a surface normal field gradient cause

California at Los Angeles, University of

Note: This page contains sample records for the topic "magnetism materials surface" from the National Library of EnergyBeta (NLEBeta).
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101

Use of magnetic carbon composites from renewable resource materials for oil spill clean up and recovery  

DOE Patents [OSTI]

A method for separating a liquid hydrocarbon material from a body of water. In one embodiment, the method includes the steps of mixing a plurality of magnetic carbon-metal nanocomposites with a liquid hydrocarbon material dispersed in a body of water to allow the plurality of magnetic carbon-metal nanocomposites each to be adhered by an amount of the liquid hydrocarbon material to form a mixture, applying a magnetic force to the mixture to attract the plurality of magnetic carbon-metal nanocomposites each adhered by an amount of the liquid hydrocarbon material, and removing said plurality of magnetic carbon-metal nanocomposites each adhered by an amount of the liquid hydrocarbon material from said body of water while maintaining the applied magnetic force, wherein the plurality of magnetic carbon-metal nanocomposites is formed by subjecting one or more metal lignosulfonates or metal salts to microwave radiation, in presence of lignin/derivatives either in presence of alkali or a microwave absorbing material.

Viswanathan, Tito

2014-02-11T23:59:59.000Z

102

The Magnificent Seven: Magnetic fields and surface temperature distributions  

E-Print Network [OSTI]

Presently seven nearby radio-quiet isolated neutron stars discovered in ROSAT data and characterized by thermal X-ray spectra are known. They exhibit very similar properties and despite intensive searches their number remained constant since 2001 which led to their name ``The Magnificent Seven''. Five of the stars exhibit pulsations in their X-ray flux with periods in the range of 3.4 s to 11.4 s. XMM-Newton observations revealed broad absorption lines in the X-ray spectra which are interpreted as cyclotron resonance absorption lines by protons or heavy ions and / or atomic transitions shifted to X-ray energies by strong magnetic fields of the order of 10^13 G. New XMM-Newton observations indicate more complex X-ray spectra with multiple absorption lines. Pulse-phase spectroscopy of the best studied pulsars RX J0720.4-3125 and RBS 1223 reveals variations in derived emission temperature and absorption line depth with pulse phase. Moreover, RX J0720.4-3125 shows long-term spectral changes which are interpreted as due to free precession of the neutron star. Modeling of the pulse profiles of RX J0720.4-3125 and RBS 1223 provides information about the surface temperature distribution of the neutron stars indicating hot polar caps which have different temperatures, different sizes and are probably not located in antipodal positions.

F. Haberl

2006-09-04T23:59:59.000Z

103

Special-purpose materials for magnetically confined fusion reactors. Third annual progress report  

SciTech Connect (OSTI)

The scope of Special Purpose Materials covers fusion reactor materials problems other than the first-wall and blanket structural materials, which are under the purview of the ADIP, DAFS, and PMI task groups. Components that are considered as special purpose materials include breeding materials, coolants, neutron multipliers, barriers for tritium control, materials for compression and OH coils and waveguides, graphite and SiC, heat-sink materials, ceramics, and materials for high-field (>10-T) superconducting magnets. It is recognized that there will be numerous materials problems that will arise during the design and construction of large magnetic-fusion energy devices such as the Engineering Test Facility (ETF) and Demonstration Reactor (DEMO). Most of these problems will be specific to a particular design or project and are the responsibility of the project, not the Materials and Radiation Effects Branch. Consequently, the Task Group on Special Purpose Materials has limited its concern to crucial and generic materials problems that must be resolved if magnetic-fusion devices are to succeed. Important areas specifically excluded include low-field (8-T) superconductors, fuels for hybrids, and materials for inertial-confinement devices. These areas may be added in the future when funding permits.

Not Available

1981-11-01T23:59:59.000Z

104

Surface Extraction from Multi-Material Components for Metrology using Dual Energy CT  

E-Print Network [OSTI]

materials (e.g., carbon-fibre-reinforced plas- tics) induce manufacturers to design new functionSurface Extraction from Multi-Material Components for Metrology using Dual Energy CT Christoph surface models of multi-material components using dual energy com- puted tomography (DECT

105

Removal of radioactive materials and heavy metals from water using magnetic resin  

DOE Patents [OSTI]

Magnetic polymer resins capable of efficient removal of actinides and heavy metals from contaminated water are disclosed together with methods for making, using, and regenerating them. The resins comprise polyamine-epichlorohydrin resin beads with ferrites attached to the surfaces of the beads. Markedly improved water decontamination is demonstrated using these magnetic polymer resins of the invention in the presence of a magnetic field, as compared with water decontamination methods employing ordinary ion exchange resins or ferrites taken separately. 9 figs.

Kochen, R.L.; Navratil, J.D.

1997-01-21T23:59:59.000Z

106

Removal of radioactive materials and heavy metals from water using magnetic resin  

DOE Patents [OSTI]

Magnetic polymer resins capable of efficient removal of actinides and heavy metals from contaminated water are disclosed together with methods for making, using, and regenerating them. The resins comprise polyamine-epichlorohydrin resin beads with ferrites attached to the surfaces of the beads. Markedly improved water decontamination is demonstrated using these magnetic polymer resins of the invention in the presence of a magnetic field, as compared with water decontamination methods employing ordinary ion exchange resins or ferrites taken separately.

Kochen, Robert L. (Boulder, CO); Navratil, James D. (Simi Valley, CA)

1997-01-21T23:59:59.000Z

107

Effect of Composition and Heat Treatment on MnBi Magnetic Materials...  

Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

Abstract: The metallic compound MnBi is a promising rare-earth-free permanent magnet material. Compare to other rare-earth-free candidates, MnBi stands out for its high...

108

Magnetic properties of Ni-Fe nanowire arrays: effect of template material and deposition conditions  

SciTech Connect (OSTI)

The objective of this work is to study the magnetic properties of arrays of Ni-Fe nanowires electrodeposited in different template materials such as porous silicon, polycarbonate and alumina. Magnetic properties were studied as a function of template material, applied magnetic field (parallel and perpendicular) during deposition, wire length, as well as magnetic field orientation during measurement. The results show that application of magnetic field during deposition strongly influences the c-axis preferred orientation growth of Ni-Fe nanowires. The samples with magnetic field perpendicular to template plane during deposition exhibits strong perpendicular anisotropy with greatly enhanced coercivity and squareness ratio, particularly in Ni-Fe nanowires deposited in polycarbonate templates. In case of polycarbonate template, as magnetic field during deposition increases, both coercivity and squareness ratio also increase. The wire length dependence was also measured for polycarbonate templates. As wire length increases, coercivity and squarness ratio decrease, but saturation field increases. Such magnetic behavior (dependence on template material, magnetic field, wire length) can be qualitatively explained by preferential growth phenomena, dipolar interactions among nanowires, and perpendicular shape anisotropy in individual nanowires.

Singleton, John [Los Alamos National Laboratory; Aravamudhan, Shyan [U OF SOUTH FL; Goddard, Paul A [U OF OXFORD; Bhansali, Shekhar [U OF SOUTH FL

2008-01-01T23:59:59.000Z

109

ELSEWER Journal of Magnetism and Magnetic Materials 169 (1997) 261-270 Superparamagnetic behavior of Fe,GaAs precipitates in GaAs  

E-Print Network [OSTI]

ELSEWER Journal of Magnetism and Magnetic Materials 169 (1997) 261-270 Superparamagnetic behavior; revised 6 December 1996 Abstract We present magnetization measurements on Fe3GaAs clusters distributed-dependent magnetization well above the blocking temperature indicate a particle size distribution in agreement

Woodall, Jerry M.

110

Surface chemistry of mesoporous materials : effect of nanopore confinement.  

SciTech Connect (OSTI)

Acid-base titration and metal sorption experiments were performed on both mesoporous alumina and alumina particles under various ionic strengths. It has been demonstrated that surface chemistry and ion sorption within nanopores can be significantly modified by a nano-scale space confinement. As the pore size is reduced to a few nanometers, the difference between surface acidity constants (pK2 - pK1) decreases, giving rise to a higher surface charge density on a nanopore surface than that on an unconfined solid-solution interface. The change in surface acidity constants results in a shift of ion sorption edges and enhances ion sorption on that nanopore surfaces.

Wang, Yifeng (Sandia National Laboratories, Carlsbad, NM); Bryan, Charles R. (Sandia National Laboratories, Carlsbad, NM); Xu, Huifang (University of New Mexico, Albuquerque, NM); Gao, Huizhen (Sandia National Laboratories, Carlsbad, NM)

2003-03-01T23:59:59.000Z

111

The crucial role of surface magnetic fields for the solar dynamo  

E-Print Network [OSTI]

Sunspots and the plethora of other phenomena occuring in the course of the 11-year cycle of solar activity are a consequence of the emergence of magnetic flux at the solar surface. The observed orientations of bipolar sunspot groups imply that they originate from toroidal (azimuthally orientated) magnetic flux in the convective envelope of the Sun. We show that the net toroidal magnetic flux generated by differential rotation within a hemisphere of the convection zone is determined by the emerged magnetic flux at the solar surface and thus can be calculated from the observed magnetic field distribution. The main source of the toroidal flux is the roughly dipolar surface magnetic field at the polar caps, which peaks around the minima of the activity cycle.

Cameron, Robert

2015-01-01T23:59:59.000Z

112

Exploring Ultrahigh Magnetic Field Processing of Materials for Developing Customized Microstructures and Enhanced Performance  

SciTech Connect (OSTI)

Thermodynamic calculations based on Gibbs free energy in the magnetization-magnetic intensity-temperature (M-H-T) magnetic equation of state space demonstrate that significantly different phase equilibria may result for those material systems where the product and parent phases exhibit different magnetization responses. These calculations show that the Gibbs free energy is changed by a factor equal to -MdH, where M and H are the magnetization and applied field strength, respectively. Magnetic field processing is directly applicable to a multitude of alloys and compounds for dramatically influencing phase stability and phase transformations. This ability to selectively control microstructural stability and alter transformation kinetics through appropriate selection of the magnetic field strength promises to provide a very robust mechanism for developing and tailoring enhanced microstructures (and even nanostructures through accelerated kinetics) with superior properties for a broad spectrum of material applications. For this Industrial Materials for the Future (IMF) Advanced Materials for the Future project, ferrous alloys were studied initially since this alloy family exhibits ferromagnetism over part of its temperature range of stability and therefore would demonstrate the maximum impact of this novel processing mechanism. Additionally, with these ferrous alloys, the high-temperature parent phase, austenite, exhibits a significantly different magnetization response from the potential product phases, ferrite plus carbide or martensite; and therefore, the solid-state transformation behavior of these alloys will be dramatically influenced by the presence of ultrahigh magnetic fields. Finally, a thermodynamic calculation capability (within ThermoCalc for example) was developed during this project to enable parametric studies to be performed to predict the magnitude of the influence of magnetic processing variables on the phase stability (phase diagrams) in ferromagnetic materials of relevance to the Industries of the Future (IOF).

Ludtka, GERALD M.

2005-03-31T23:59:59.000Z

113

Surface space : digital manufacturing techniques and emergent building material  

E-Print Network [OSTI]

This thesis explores tectonic possibilities of new material and forming techniques. The design process is catalyzed by experimenting different configurations of the material.This project attempts to develop inventive ways ...

Ho, Joseph Chi-Chen, 1975-

2002-01-01T23:59:59.000Z

114

Fermi Surface of Uranium at Ambient Pressure Gregory S. Boebinger, National High Magnetic Field Laboratory  

E-Print Network [OSTI]

Fermi Surface of ­Uranium at Ambient Pressure Gregory S. Boebinger, National High Magnetic Field Laboratory DMR-Award 0654118 DC Field Facility User Program The fermi surface of ­Uranium has been measured surface of alpha-uranium at ambient pressure, Phys. Rev. B Rapid Commun., 80, 241101 (2009). B//c-axis B

Weston, Ken

115

An in-situ accelerator-based diagnostic for plasma-material interactions science in magnetic fusion devices  

E-Print Network [OSTI]

Plasma-material interactions (PMI) in magnetic fusion devices such as fuel retention, material erosion and redeposition, and material mixing present significant scientific and engineering challenges, particularly for the ...

Hartwig, Zachary Seth

2014-01-01T23:59:59.000Z

116

Seeing the magnetic monopole through the mirror of topological surface states  

SciTech Connect (OSTI)

Existence of the magnetic monopole is compatible with the fundamental laws of nature, however, this illusive particle has yet to be detected experimentally. In this work, we show that an electric charge near the topological surface state induces an image magnetic monopole charge due to the topological magneto-electric effect. The magnetic field generated by the image magnetic monopole can be experimentally measured, and the inverse square law of the field dependence can be determined quantitatively. We propose that this effect can be used to experimentally realize a gas of quantum particles carrying fractional statistics, consisting of the bound states of the electric charge and the image magnetic monopole charge.

Qi, Xiao-Liang; Li, Rundong; /Stanford U., Phys. Dept.; Zang, Jiadong; /Fudan U.; Zhang, Shou-Cheng; /Stanford U., Phys. Dept. /Fudan U.

2010-03-25T23:59:59.000Z

117

Abstract --In electromagnetic applications, hysteresis phenomena in magnetic materials are responsible of  

E-Print Network [OSTI]

rotation. Furthermore, based on the balance of chemical equation analogies, this model has the advantage13. M M Abstract -- In electromagnetic applications, hysteresis phenomena in magnetic materials the implementation proceeding used for some hysteresis material models and how they are applied in a sensor study

Boyer, Edmond

118

Wave Turbulence on the Surface of a Ferrofluid in a Magnetic Field Francois Boyer and Eric Falcon*  

E-Print Network [OSTI]

Wave Turbulence on the Surface of a Ferrofluid in a Magnetic Field Franc¸ois Boyer and Eric Falcon the observation of wave turbulence on the surface of a ferrofluid mechanically forced and submitted to a static normal magnetic field. We show that magnetic surface waves arise only above a critical field. The power

Falcon, Eric

119

Wave turbulence on the surface of a ferrofluid submitted to a magnetic field Francois Boyer and Eric Falcon  

E-Print Network [OSTI]

Wave turbulence on the surface of a ferrofluid submitted to a magnetic field Fran¸cois Boyer the observation of wave turbulence on the surface of a ferrofluid mechanically forced and submitted to a static normal magnetic field. We show that magnetic surface waves arise only above a critical field. The power

Paris-Sud XI, Université de

120

Assessment of Structural and Clad Materials for Fission Surface...  

Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

1413 Reactor Pressure Vessel Task of Light Water Reactor Sustainability Program: Milestone Report on Materials and Machining of Specimens for the ATR-2 Experiment January 2011...

Note: This page contains sample records for the topic "magnetism materials surface" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


121

Journal of Magnetism and Magnetic Materials 288 (2005) 196204 Micromagnetic studies of nickel microbars fabricated by  

E-Print Network [OSTI]

Abstract Micromagnetic configurations and macromagnetic properties of electrodeposited nickel microbars: 75.50.Cc; 75.75.+a; 81.15.Pq Keywords: Electrodeposited nickel; Magnetic microbar; Magnetic vortex (VSM) studies of nickel microbars with round corners, produced by nanoimprinting and electrodeposition

Pesic, Batric

2005-01-01T23:59:59.000Z

122

Improved Bounds on the Effective Yield Surface of Inhomogeneous Rigid/Plastic Materials  

E-Print Network [OSTI]

Improved Bounds on the Effective Yield Surface of Inhomogeneous Rigid/Plastic Materials Tamara January 1993 Abstract The yield surface of a mixture of rigid/perfectly­plastic materials is examined plasticity under suffi­ ciently large stress. The set of stresses at which the deformation changes from

Olson, Tamara

123

Self assembled molecular monolayers on high surface area materials as molecular getters  

DOE Patents [OSTI]

The present invention relates to a gettering material that may be used as a filtration medium to remove pollutants from the environment. The gettering material comprises a high surface area material having a metal surface that chemically bonds n-alkanethiols in an organized manner thereby forming a molecular monolayer over the metal surface. The n-alkanethiols have a free functional group that interacts with the environment thereby binding specific pollutants that may be present. The gettering material may be exposed to streams of air in heating, ventilation, and air conditioning systems or streams of water to remove specific pollutants from either medium. 9 figs.

King, D.E.; Herdt, G.C.; Czanderna, A.W.

1997-01-07T23:59:59.000Z

124

Self assembled molecular monolayers on high surface area materials as molecular getters  

DOE Patents [OSTI]

The present invention relates to a gettering material that may be used as a filtration medium to remove pollutants from the environment. The gettering material comprises a high surface area material having a metal surface that chemically bonds n-alkanethiols in an organized manner thereby forming a molecular monolayer over the metal surface. The n-alkanethiols have a free functional group that interacts with the environment thereby binding specific pollutants that may be present. The gettering material may be exposed to streams of air in heating, ventilation, and air conditioning systems or streams of water to remove specific pollutants from either medium.

King, David E. (Lakewood, CO); Herdt, Gregory C. (Denver, CO); Czanderna, Alvin W. (Denver, CO)

1997-01-01T23:59:59.000Z

125

Surface Properties of Advanced Materials and Their Applications in Ballistics  

E-Print Network [OSTI]

to facilitate design and development of new materials for tribological applications. The research will focus on improving of the gun barrel performances. Experimental approaches will be used for combining analysis with basic thermal energy transfer principles...

Yun, Huisung

2010-07-23T23:59:59.000Z

126

Use of High Magnetic Fields to Improve Material Properties for Hydraulics, Automotive and Truck Components  

SciTech Connect (OSTI)

In this CRADA, research and development activities were successfully conducted on magnetic processing effects for the purpose of manipulating microstructure and the application specific performance of three alloys provided by Eaton (alloys provided were: carburized steel, plain low carbon steel and medium carbon spring steel). Three specific industrial/commercial application areas were considered where HMFP can be used to provide significant energy savings and improve materials performance include using HMFP to: 1.) Produce higher material strengths enabling higher torque bearing capability for drive shafts and other motor components; 2.) Increase the magnetic response in an iron-based material, thereby improving its magnetic permeability resulting in improved magnetic coupling and power density, and 3.) Improve wear resistance. The very promising results achieved in this endeavor include: 1.) a significant increase in tensile strength and a major reduction in volume percent retained austenite for the carburized alloy, and 2.) a substantial improvement in magnetic perm respect to a no-field processed sample (which also represents a significant improvement over the nominal conventional automotive condition of no heat treatment). The successful completion of these activities has resulted in the current 3-year CRADA No. NFE-09-02522 Prototyping Energy Efficient ThermoMagnetic and Induction Hardening for Heat Treat and Net Shape Forming Applications .

Ludtka, Gerard Michael [ORNL; Ludtka, Gail Mackiewicz- [ORNL; Wilgen, John B [ORNL; Kisner, Roger A [ORNL; Ahmad, Aquil [Eaton Corporation

2010-08-01T23:59:59.000Z

127

Reduction of surface leakage current by surface passivation of CdZn Te and other materials using hyperthermal oxygen atoms  

DOE Patents [OSTI]

Reduction of surface leakage current by surface passivation of Cd.sub.1-x Zn.sub.x Te and other materials using hyperthermal oxygen atoms. Surface effects are important in the performance of CdZnTe room-temperature radiation detectors used as spectrometers since the dark current is often dominated by surface leakage. A process using high-kinetic-energy, neutral oxygen atoms (.about.3 eV) to treat the surface of CdZnTe detectors at or near ambient temperatures is described. Improvements in detector performance include significantly reduced leakage current which results in lower detector noise and greater energy resolution for radiation measurements of gamma- and X-rays, thereby increasing the accuracy and sensitivity of measurements of radionuclides having complex gamma-ray spectra, including special nuclear materials.

Hoffbauer, Mark A. (Los Alamos, NM); Prettyman, Thomas H. (Los Alamos, NM)

2001-01-01T23:59:59.000Z

128

Production of Materials with Superior Properties Utilizing High Magnetic  

Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

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129

Materials Physics Applications: The National High Magnetic Field Laboratory  

Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

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130

THERMAL IMAGING OF ACTIVE MAGNETIC REGERNERATOR MCE MATERIALS DURING OPERATION  

SciTech Connect (OSTI)

An active magnetic regenerator (AMR) prototype was constructed that incorporates a Gd sheet into the regenerator wall to enable visualization of the system s thermal transients. In this experiment, the thermal conditions inside the AMR are observed under a variety of operating conditions. An infrared (IR) camera is employed to visualize the thermal transients within the AMR. The IR camera is used to visually and quantitatively evaluate the temperature difference and thus giving means to calculate the performance of the system under the various operating conditions. Thermal imaging results are presented for two differing experimental test runs. Real time imaging of the thermal state of the AMR has been conducted while operating the system over a range of conditions. A 1 Tesla twin-coil electromagnet (situated on a C frame base) is used for this experiment such that all components are stationary during testing. A modular, linear reciprocating system has been realized in which the effects of regenerator porosity and utilization factor can be investigated. To evaluate the performance variation in porosity and utilization factor the AMR housing was constructed such that the plate spacing of the Gd sheets may be varied. Each Gd sheet has dimensions of 38 mm wide and 66 mm long with a thickness of 1 mm and the regenerator can hold a maximum of 29 plates with a spacing of 0.25 mm. Quantitative and thermal imaging results are presented for several regenerator configurations.

Shassere, Benjamin [ORNL] [ORNL; West, David L [ORNL] [ORNL; Abdelaziz, Omar [ORNL] [ORNL; Evans III, Boyd Mccutchen [ORNL] [ORNL

2012-01-01T23:59:59.000Z

131

Surface Finish Modeling in Micromilling of Biocompatible Materials  

E-Print Network [OSTI]

the requirements listed above. Computer controlled micromilling on a high speed machine system in minimum quantity lubrication was used to remove most materials and define a channel pattern. Microchannels were machined with ball end mills of diameters from Ø152?m...

Berestovskyi, Dmytro V

2013-06-05T23:59:59.000Z

132

Neutron star envelopes and thermal radiation from the magnetic surface  

E-Print Network [OSTI]

The thermal structure of neutron star envelopes is discussed with emphasis on analytic results. Recent progress on the effect of chemical constitution and high magnetic fields on the opacities and the thermal structure is further reviewed in view of the application to pulsar cooling and magnetars.

J. Ventura; A. Y. Potekhin

2001-03-31T23:59:59.000Z

133

Carbon-Based Materials, High-Surface-Area Sorbents, and New Materials...  

Office of Energy Efficiency and Renewable Energy (EERE) Indexed Site

technologies includes a range of carbon-based materials such as carbon nanotubes, aerogels, nanofibers (including metal-doped hybrids), as well as metal-organic frameworks,...

134

Magnetic tunable microstructured surfaces for thermal management and microfluidic applications  

E-Print Network [OSTI]

Micro and nanostructured surfaces have broad applications including heat transfer enhancement in phase-change systems and liquid manipulation in microfluidic devices. While significant efforts have focused on fabricating ...

Zhu, Yangying

2013-01-01T23:59:59.000Z

135

XPS Analysis of Nanostructured Materials and Biological Surfaces. | EMSL  

Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

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136

Multi-Instrument Characterization of the Surfaces and Materials in  

Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE:1 First Use of Energy for All Purposes (Fuel and Nonfuel),Feet) Year Jan Feb Mar Apr MayAtmospheric Optical Depth7-1D: VegetationEquipment SurfacesResource ProgramModification andinterface1JUN 2 5 2014Mud E.

137

Surface-Modified Active Materials for Lithium Ion Battery Electrodes -  

Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE:1 First Use of Energy for All Purposes (Fuel and Nonfuel),Feet) Year Jan Feb Mar Apr MayAtmosphericNuclear Security AdministrationcontrollerNanocrystalline GalliumSuppression of conductivitySurfaceEnergy Innovation

138

neutron scattering shows magnetic excitation mechanism at work in new materials.  

E-Print Network [OSTI]

neutron scattering shows magnetic excitation mechanism at work in new materials. In 2008 dai of orNl and the university of tennes- see led early neutron scattering studies of the pnictides. dai ticks off four main things neutron scattering has revealed about superconducting iron com- pounds

139

Magnetic properties of materials for MR engineering, micro-MR and beyond  

E-Print Network [OSTI]

We present the results of a systematic measurement of the magnetic susceptibility of small material samples in a 9.4 T MRI scanner. We measured many of the most widely used materials in MR engineering and MR micro technology, including various polymers, optical and substrate glasses, resins, glues, photoresists, PCB substrates and some fluids. Based on our data, we identify particularly suitable materials with susceptibilities close to water. For polyurethane resins and elastomers, we also show the MR spectra, as they may be a good substitute for silicone elastomers and good casting resins.

Wapler, Matthias C; Dragonu, Iulius; von Elverfeld, Dominik; Zaitsev, Maxim; Wallrabe, Ulrike

2014-01-01T23:59:59.000Z

140

Materials of interaction : responsive materials in the design of transformable interactive surfaces  

E-Print Network [OSTI]

Materials that embody computational properties are reshaping the ways in which we design, interact and communicate. This thesis looks at the topic of form transformation and how to bring the programmability and versatility ...

Coelho, Marcelo

2008-01-01T23:59:59.000Z

Note: This page contains sample records for the topic "magnetism materials surface" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


141

Rheological behavior and cryogenic properties of cyanate ester/epoxy insulation material for fusion superconducting magnet  

SciTech Connect (OSTI)

In a Tokamak fusion reactor device like ITER, insulation materials for superconducting magnets are usually fabricated by a vacuum pressure impregnation (VPI) process. Thus these insulation materials must exhibit low viscosity, long working life as well as good radiation resistance. Previous studies have indicated that cyanate ester (CE) blended with epoxy has an excellent resistance against neutron irradiation which is expected to be a candidate insulation material for a fusion magnet. In this work, the rheological behavior of a CE/epoxy (CE/EP) blend containing 40% CE was investigated with non-isothermal and isothermal viscosity experiments. Furthermore, the cryogenic mechanical and electrical properties of the composite were evaluated in terms of interlaminar shear strength and electrical breakdown strength. The results showed that CE/epoxy blend had a very low viscosity and an exceptionally long processing life of about 4 days at 60 °C.

Wu, Z. X.; Huang, C. J. [Key Laboratory of Cryogenics, Technical Institute of Physics and Chemistry, Chinese Academy of Sciences, Beijing 100190, PR (China); Li, L. F. [Key Laboratory of Cryogenics, Technical Institute of Physics and Chemistry, Chinese Academy of Sciences, Beijing 100190, PR China and State Key Laboratory of Technologies in Space Cryogenic Propellants, Technical Institute of Physics and Chemistry, C (China); Li, J. W. [Key Laboratory of Cryogenics, Technical Institute of Physics and Chemistry, Chinese Academy of Sciences, Beijing 100190, PR China and University of Chinese Academy of Sciences, Beijing 100049, PR (China); Tan, R.; Tu, Y. P. [North China Electric Power University, Beijing 102206, PR (China)

2014-01-27T23:59:59.000Z

142

Ultra-low field nuclear magnetic resonance and magnetic resonance imaging to discriminate and identify materials  

DOE Patents [OSTI]

Method comprising obtaining an NMR measurement from a sample wherein an ultra-low field NMR system probes the sample and produces the NMR measurement and wherein a sampling temperature, prepolarizing field, and measurement field are known; detecting the NMR measurement by means of inductive coils; analyzing the NMR measurement to obtain at least one measurement feature wherein the measurement feature comprises T1, T2, T1.rho., or the frequency dependence thereof; and, searching for the at least one measurement feature within a database comprising NMR reference data for at least one material to determine if the sample comprises a material of interest.

Matlashov, Andrei Nikolaevich; Urbaitis, Algis V.; Savukov, Igor Mykhaylovich; Espy, Michelle A.; Volegov, Petr Lvovich; Kraus, Jr., Robert Henry

2013-03-05T23:59:59.000Z

143

Nanocluster-based white-light-emitting material employing surface tuning  

DOE Patents [OSTI]

A method for making a nanocrystal-based material capable of emitting light over a sufficiently broad spectral range to appear white. Surface-modifying ligands are used to shift and broaden the emission of semiconductor nanocrystals to produce nanoparticle-based materials that emit white light.

Wilcoxon, Jess P. (Albuquerque, NM); Abrams, Billie L. (Albuquerque, NM); Thoma, Steven G. (Albuquerque, NM)

2007-06-26T23:59:59.000Z

144

Surface Acoustic Waves in an Infinite Plate of Functionally Graded Materials  

E-Print Network [OSTI]

and thermal constants, to improve certain functions like thermal resistance and local strength in variousSurface Acoustic Waves in an Infinite Plate of Functionally Graded Materials Ji Wang, Lehui Zhou, and Jianke Du Piezoelectric Device Laboratory, Mechanics and Materials Science Research Center, School

Wang, Ji

145

Equilibrium behavior of sessile drops under surface tension, applied external fields, and material variations  

E-Print Network [OSTI]

Equilibrium behavior of sessile drops under surface tension, applied external fields, and material properties such as dielectric constants, resistivities, and surface tension coefficients. The analysis energy storage in the liquid, will lead to 1/R ``line-tension''-type terms if and only if the energy

Shapiro, Benjamin

146

Experimental studies of lithium-based surface chemistry for fusion plasma-facing materials applications q  

E-Print Network [OSTI]

- ments of plasma-surface interactions in tokamaks such as NSTX. Results suggest that the lithium bondingExperimental studies of lithium-based surface chemistry for fusion plasma-facing materials.65.y a b s t r a c t Lithium has enhanced the operational performance of fusion devices such as: TFTR

Harilal, S. S.

147

Cavitation in elastomeric solids: II--Onset-of-cavitation surfaces for Neo-Hookean materials  

E-Print Network [OSTI]

Cavitation in elastomeric solids: II--Onset-of-cavitation surfaces for Neo-Hookean materials Oscar a fairly general theory of cavitation in elastomeric solids based on the sudden growth of pre-existing defects. In this article, the theory is used to determine onset-of-cavitation surfaces for Neo

Lopez-Pamies, Oscar

148

Cavitation in elastomeric solids: II--Onset-of-cavitation surfaces for Neo-Hookean materials  

E-Print Network [OSTI]

Cavitation in elastomeric solids: II--Onset-of-cavitation surfaces for Neo-Hookean materials Oscar of cavitation in elastomeric solids based on the sudden growth of pre-existing defects. In this article, the theory is used to determine onset-of-cavitation surfaces for Neo-Hookean solids where the defects

Nakamura, Toshio

149

Atomic Di usion from a Material Surface into a Grain Boundary  

E-Print Network [OSTI]

was #12;rst reduced to an eigen- value problem with a 1-d-integro-di#11;erential operator from the surface of a material into a semi-in#12;nite grain boundary orthogonal to the surface in a strip and then to a Riemann-Hilbert boundary- value problem for an open contour that admits solution

Bath, University of

150

Magnetic measurement to evaluate material properties of ferromagnetic structural steels with planar coils  

SciTech Connect (OSTI)

The mechanical properties of a nuclear reactor pressure vessel (RPV) are degraded by fast neutron irradiation during operation. This is well-known as so-called as radiation embrittlement of RPV and an important problem to be considered in the assessment of residual life of the nuclear reactor. Hence the development of nondestructive means is required to measure directly the degree of material degradation in RPV. Here, nondestructive measurement experiments were carried out with a planar coil to evaluate changes of material properties of ferromagnetic structural steels. Examined steels were of A533B that is a low-alloy steel and of SUS410 that is a martensitic stainless steel. The planar coil has two windings; one is of primary for excitation and the other secondary for induction of output voltage. The coil was placed on a test plate with a magnetic yoke for application of a bias dc magnetic field, and excited with a constant current of 25 Hz. Then the output voltages were measured while slowly changing the bias field by excitation of the magnetic yoke with a triangular-wave form current of 0.005 Hz. Changes of output voltages with different test plates were correlated with their mechanical and magnetic properties. The correlation is so good that this measuring method could be applied to nondestructive evaluation of material degradation in ferromagnetic structural steels.

Ebine, Noriya; Ara, Katsuyuki

1999-09-01T23:59:59.000Z

151

Propagation of surface waves on a semi-bounded quantum magnetized collisional plasma  

SciTech Connect (OSTI)

The propagation of surface waves on a semi-bounded quantum plasma in the presence of the external magnetic field and collisional effects is investigated by using quantum magnetohydrodynamics model. A general analytical expression for the dispersion relation of surface waves is obtained by considering the boundary conditions. It is shown that, in some special cases, the obtained dispersion relation reduces to the results reported in previous works. It is also indicated that the quantum, external magnetic field and collisional effects can facilitate the propagation of surface waves on a semi-bounded plasma. In addition, it is found that the growth rate of the surface wave instability is enhanced by increasing the collision frequency and plasmonic parameter.

Niknam, A. R. [Laser and Plasma Research Institute, Shahid Beheshti University, G.C., Tehran (Iran, Islamic Republic of)] [Laser and Plasma Research Institute, Shahid Beheshti University, G.C., Tehran (Iran, Islamic Republic of); Taheri Boroujeni, S.; Khorashadizadeh, S. M. [Physics Department, University of Birjand, Birjand (Iran, Islamic Republic of)] [Physics Department, University of Birjand, Birjand (Iran, Islamic Republic of)

2013-12-15T23:59:59.000Z

152

Magnetic Flux Transport Simulations of Solar Surface Magnetic Distributions During a Grand Minimum.  

E-Print Network [OSTI]

, Scotland, KY16 9SS. Abstract. It is well known that magnetic activity on the Sun modulates from one cycle strongly depend on the phase of the cycle in which the grand minimum starts and whether it lasts for an odd or even number of cycles. If the grand minimum starts around cycle minimum then a signi#12;cant amount

Mackay, Duncan

153

A PARAMETRIC STUDY OF BCS RF SURFACE IMPEDANCE WITH MAGNETIC FIELD USING THE XIAO CODE  

SciTech Connect (OSTI)

A recent new analysis of field-dependent BCS rf surface impedance based on moving Cooper pairs has been presented.[1] Using this analysis coded in Mathematica TM, survey calculations have been completed which examine the sensitivities of this surface impedance to variation of the BCS material parameters and temperature. The results present a refined description of the "best theoretical" performance available to potential applications with corresponding materials.

Reece, Charles E. [JLAB; Xiao, Binping [JLAB, BNL

2013-09-01T23:59:59.000Z

154

Critical magnetic field of surface superconductivity in lead  

SciTech Connect (OSTI)

The critical superconductivity field H{sub c3} is measured on lead single crystals. It is shown that the temperature dependence of H{sub c3}/H{sub c} in the vicinity of superconducting transition temperature T{sub c} is essentially nonlinear. Relative changes in the value of H{sub c3}/H{sub c} reach approximately 30%, which cannot be described by the Ginzburg-Landau theory. The experimental temperature dependences lead to the conclusion that the surface superconducting transition temperature noticeably exceeds the superconducting transition temperature in the bulk of the semiconductor. The differences in the critical temperatures and in the Ginzburg-Landau parameters for lead are estimated.

Khlyustikov, I. N., E-mail: khly@kapitza.ras.ru [Russian Academy of Sciences, Kapitza Institute of Physical Problems (Russian Federation)

2011-12-15T23:59:59.000Z

155

Need for development of higher strength cryogenic structural materials for fusion magnet  

SciTech Connect (OSTI)

A prototype fusion reactor is targeted as a beyond ITER project which is so called DEMO. Several conceptual designs have been carried out. Recently, in order to recognize practical aspects on maintenance of the prototype reactor, the replacement procedure of in-vessel components was focused and “sector process” was proposed. The process is that the reactor consists of sectors and all sectors will be drowned and replaced in a short time. The slim coil which generated higher magnetic field is required to realize the sector process. From the point of coil design, the occupancy of the structural material on the cross section of the coil increases with an increase of magnetic field. To realize the slim coil, the cryogenic structural material with higher yield strength and the proper toughness is desired.

Nishimura, Arata [ITER Organization, Route de Vinon sur Verdon, 13115 St Paul Lez Durance (France)

2014-01-27T23:59:59.000Z

156

Surface-gasification materials program. Semiannual progress report for the period ending March 31, 1982  

SciTech Connect (OSTI)

The objective of the Surface Gasification Materials Program is to conduct research and development on materials for application to the specific needs of coal gasification systems. The Program is divided into two subprograms: (1) the Gasification Systems Fabrication Technology Program and (2) the Materials Application and Development Program. The purpose of the Gasification Systems Fabrication Technology Program is to evaluate innovative fabrication methods which have the potential to lower costs and improve reliability and safety for gasifier vessels and components. The purpose of the Materials Application and Development Program is to conduct engineering-scale development and application of materials for coal gasification systems to ensure that the materials of construction for pilot plants and future large-scale plants can be properly selected and specified. The management of materials projects in support of surface gasification sponsored by the Headquarters DOE Gasification Division has been defined in an April 16, 1982 METC-sponsored agreement transmitted to DOE field offices and performing contractors. This agreement recognizes the lead role in fossil energy materials delegated by METC to the DOE Oak Ridge Operations Office and the Oak Ridge National Laboratory. The ORNL Fossil Energy Materials Program Office compiles and issues this combined semiannual progress report from camera-ready copies submitted by each of the participating organizations. Distribution is as shown on pages 59 to 63. Future reports will be issued on a semiannual basis to a similar distribution.

Not Available

1982-08-01T23:59:59.000Z

157

Surface Gasification Materials Program. Semiannual progress report for the period ending September 30, 1982  

SciTech Connect (OSTI)

The objective of the Surface Gasification Materials Program is to conduct research and development on materials for application to the specific needs of coal gasification systems. The Program is divided into two subprograms: (1) the Gasification Systems Fabrication Technology Program and (2) the Materials Application and Development Program. The purpose of the Gasification Systems Fabrication Technology Program is to evaluate innovative fabrication methods which have the potential to lower costs and improve reliability and safety for gasifier vessels and components. The purpose of the Materials Application and Development Program is to conduct engineering-scale development and application of materials for coal gasification systems to ensure that the materials of construction for pilot plants and future large-scale plants can be properly selected and specified. The Morgantown Energy Technology Center (METC), in its lead role for gasification projects, is responsible for ensuring that the Surface Gasification Materials Program is responsive to the needs for gasification systems. Under its lead role for fossil energy materials, the Oak Ridge Operations Office (ORO), is responsible for the planning, implementation, and management of the program in accordance with guidance received from METC. The ORNL Fossil Energy Materials Program Office compiles and issues this combined semiannual progress report from camera-ready copies submitted by each of the participating organizations.

Not Available

1982-12-01T23:59:59.000Z

158

Massive Dirac Fermion on the Surface of a Magnetically Doped Topological Insulator  

SciTech Connect (OSTI)

Topological insulators are characterized by a massless Dirac surface state and a bulk energy gap. An insulating massive Dirac fermion state is predicted to occur if the breaking of the time reversal symmetry opens an energy gap at the Dirac point, provided that the Fermi-energy resides inside both the surface and bulk gaps. By introducing magnetic dopants into the three dimensional topological insulator Bi{sub 2}Se{sub 3} to break the time reversal symmetry, we observed the formation of a massive Dirac fermion on the surface; simultaneous magnetic and charge doping furthermore positioned the Fermi-energy inside the Dirac gap. The insulating massive Dirac Fermion state thus obtained may provide a tool for studying a range of topological phenomena relevant to both condensed matter and particle physics.

Chen, Y.L.; Chu, J.-H.; Analytis, J.G.; Liu, Z.K.; Igarashi, K.; Kuo, H.-H.; Qi, X.L.; Mo, S.K.; Moore, R.G.; Lu, D.H.; Hashimoto, M.; Sasagawa, T.; Zhang, S.C.; Fisher, I.R.; Hussain, Z.; Shen, Z.-X.; /SLAC; ,

2011-05-20T23:59:59.000Z

159

Nanostructured materials for lithium-ion batteries: Surface conductivity vs. bulk  

E-Print Network [OSTI]

Nanostructured materials for lithium-ion batteries: Surface conductivity vs. bulk ion cathode materials for high capacity lithium-ion batteries. Owing to their inherently low electronic-ion batteries. Lithium transition metal phosphates such as LiFePO4,1 LiMnPO4,2 Li3V2(PO4)3 3 and LiVPO4F4 have

Ryan, Dominic

160

(1) Frank May REU Summary 2012 -http://engineering.umass.edu/reu/2012/reu-students (2) "Hard Magnetic Materials: A Perspecitve" J.M.D. Coey  

E-Print Network [OSTI]

(1) Frank May REU Summary 2012 - http://engineering.umass.edu/reu/2012/reu-students (2) "Hard Magnetic Materials: A Perspecitve" J.M.D. Coey (3) "Perspecitve on Permanent Magnetic Materials for Energy of L10 magnetic materials" David E. Laughlin, Kumar Srinivasan, Mihaela Tanase, Lisha Wang (5) "A study

Mountziaris, T. J.

Note: This page contains sample records for the topic "magnetism materials surface" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


161

Simulation Study of Internal and Surface waves of Vertically Vibrated Granular Materials  

E-Print Network [OSTI]

Molecular dynamical (MD) simulations are performed to simulate two dimensional vibrofluidized granular materials in this work. Statistics on simulation results indicate that there exist shocks propagating upward in each vibrating cycle. Under certain driving parameters surface waves similar to Faraday instability in normal fluid coexist with internal waves. Relationship between the two kinds of waves is explored. Moreover simulation results indicate that periodically structured bottom can change the dispersion relationship and amplitude of surface waves.

Kai Huang; Guoqing Miao; Peng Zhang; Yifei Zhu; Rongjue Wei

2005-11-29T23:59:59.000Z

162

Hyper-resistivity and electron thermal conductivity due to destroyed magnetic surfaces in axisymmetric plasma equilibria  

SciTech Connect (OSTI)

In order to model the effects of small-scale current-driven magnetic fluctuations in a mean-field theoretical description of a large-scale plasma magnetic field B(x,t), a space and time dependent hyper-resistivity {Lambda}(x,t) can be incorporated into the Ohm's law for the parallel electric field E Dot-Operator B. Using Boozer coordinates, a theoretical method is presented that allows for a determination of the hyper-resistivity {Lambda}({psi}) functional dependence on the toroidal magnetic flux {psi} for arbitrary experimental steady-state Grad-Shafranov axisymmetric plasma equilibria, if values are given for the parallel plasma resistivity {eta}({psi}) and the local distribution of any auxiliary plasma current. Heat transport in regions of plasma magnetic surfaces destroyed by resistive tearing modes can then be modeled by an electron thermal conductivity k{sub e}({psi})=({epsilon}{sub 0}{sup 2}m{sub e}/e{sup 2}){Lambda}({psi}), where e and m{sub e} are the electron charge and mass, respectively, while {epsilon}{sub 0} is the permittivity of free space. An important result obtained for axisymmetric plasma equilibria is that the {psi}{psi}-component of the metric tensor of Boozer coordinates is given by the relation g{sup {psi}{psi}}({psi}){identical_to}{nabla}{psi} Dot-Operator {nabla}{psi}=[{mu}{sub 0}G({psi})][{mu}{sub 0}I({psi})]/{iota}({psi}), with {mu}{sub 0} the permeability of free space, G({psi}) the poloidal current outside a magnetic surface, I({psi}) the toroidal current inside a magnetic surface, and {iota}({psi}) the rotational transform.

Weening, R. H. [Department of Radiologic Sciences, Thomas Jefferson University, 901 Walnut Street, Philadelphia, Pennsylvania 19107-5233 (United States)

2012-06-15T23:59:59.000Z

163

Hamilton--Jacobi theory for continuation of magnetic field across a toroidal surface supporting a plasma pressure discontinuity  

E-Print Network [OSTI]

The vanishing of the divergence of the total stress tensor (magnetic plus kinetic) in a neighborhood of an equilibrium plasma containing a toroidal surface of discontinuity gives boundary and jump conditions that strongly constrain allowable continuations of the magnetic field across the surface. The boundary conditions allow the magnetic fields on either side of the discontinuity surface to be described by surface magnetic potentials, reducing the continuation problem to that of solving a Hamilton--Jacobi equation. The characteristics of this equation obey Hamiltonian equations of motion, and a necessary condition for the existence of a continued field across a general toroidal surface is that there exist invariant tori in the phase space of this Hamiltonian system. It is argued from the Birkhoff theorem that existence of such an invariant torus is also, in general, sufficient for continuation to be possible. An important corollary is that the rotational transform of the continued field on a surface of discontinuity must, generically, be irrational.

M. McGann; S. R. Hudson; R. L. Dewar; G. von Nessi

2010-02-18T23:59:59.000Z

164

W.E. Henry Symposium compendium: The importance of magnetism in physics and material science  

SciTech Connect (OSTI)

This compendium contains papers presented at the W. E. Henry Symposium, The Importance of Magnetism in Physics and Material Science. The one-day symposium was conducted to recognize the achievements of Dr. Warren Elliot Henry as educator, scientist, and inventor in a career spanning almost 70 years. Dr. Henry, who is 88 years old, attended the symposium. Nobel Laureate, Dr. Glenn Seaborg, a friend and colleague for over 40 years, attended the event and shared his personal reminiscences. Dr. Seaborg is Associate Director-At-Large at the Lawrence Berkeley National Laboratory. The Compendium begins with three papers which demonstrate the ongoing importance of magnetism in physics and material science. Other contributions cover the highlights of Dr. Henry`s career as a researcher, educator, and inventor. Colleagues and former students share insights on the impact of Dr. Henry`s research in the field of magnetism, low temperature physics, and solid state physics; his influence on students as an educator; and his character, intellect and ingenuity, and passion for learning and teaching. They share a glimpse of the environment and times that molded him as a man, and the circumstances under which he made his great achievements despite the many challenges he faced.

Carwell, H.

1997-09-19T23:59:59.000Z

165

Materials Science and Engineering B 126 (2006) 230235 Alloying, co-doping, and annealing effects on the magnetic and optical  

E-Print Network [OSTI]

are formed. Atomic force microscopy revealed MOCVD-like step flow growth patterns and a mean surface consist of semi- conductors doped with rare earth or transition metals to provide magnetic functionality on the magnetic and optical properties of MOCVD-grown Ga1-xMnxN Matthew H. Kanea,b, Martin Strassburga,d, Ali

Dietz, Nikolaus

166

& Surface Chemistry Water-Stable Zirconium-Based MetalOrganic Framework Material  

E-Print Network [OSTI]

& Surface Chemistry Water-Stable Zirconium-Based Metal­Organic Framework Material with High candidates as replacements for gasoline (petrol). However, their compact storage in molecular form, es Department of Chemistry and International Institute for Nanotechnology Northwestern University, 2145 Sheridan

167

Effluent and Material Management from Barge Work Surfaces for Large Bridge  

E-Print Network [OSTI]

Effluent and Material Management from Barge Work Surfaces for Large Bridge Department of Transporta:on Office of Environmental Stewardship #12;Environmental · Drill shaT slurry seUling effec:ve treatment · SoT soil and wetland func

Minnesota, University of

168

Effect of Composition and Heat Treatment on MnBi Magnetic Materials  

SciTech Connect (OSTI)

The metallic compound MnBi is a promising rare-earth-free permanent magnet material. Compare to other rare-earth-free candidates, MnBi stands out for its high intrinsic coercivity (Hci) and its large positive temperature coefficient. Several groups have demonstrated that the Hci of MnBi compound in thin film or in powder form can exceed 12 kOe and 26 kOe at 300 K and 523 K, respectively. Such steep increase in Hci with increasing temperature is unique to MnBi. Consequently, MnBi is a highly sought-after hard phase for exchange coupling nanocomposite magnets. The reaction between Mn and Bi is peritectic, so Mn tends to precipitate out of the MnBi liquid during the solidification process. As result, the composition of the Mn-Bi alloy with the largest amount of the desired LTP (low temperature phase) MnBi and highest saturation magnetization will be over-stoichiometric and rich in Mn. The amount of additional Mn required to compensate the Mn precipitation depends on solidification rate: the faster the quench speed, the less Mn precipitates. Here we report a systematic study of the effect of composition and heat treatments on the phase contents and magnetic properties of Mn-Bi alloys. In this study, Mn-Bi alloys with 14 compositions were prepared using conventional metallurgical methods such as arc melting and vacuum heat treatment, and the obtained alloys were analyzed for compositions, crystal structures, phase content, and magnetic properties. The results show that the composition with 55 at.% Mn exhibits the highest LTP MnBi content and the highest magnetization. The sample with this composition shows >90 wt.% LTP MnBi content. Its measured saturation magnetization is 68 emu/g with 2.3 T applied field at 300 K; its coercivity is 13 kOe and its energy product is 12 MGOe at 300 K. A bulk magnet fabricated using this powder exhibits an energy product of 8.2 MGOe.

Cui, Jun; Choi, Jung-Pyung; Polikarpov, Evgueni; Bowden, Mark E.; Xie, Wei; Li, Guosheng; Nie, Zimin; Zarkevich, Nikolai; Kramer, Matthew J.; Johnson, Duane D.

2014-08-17T23:59:59.000Z

169

Surface driven effects on magnetic properties of antiferromagnetic LaFeO{sub 3} nanocrystalline ferrite  

SciTech Connect (OSTI)

LaFeO{sub 3} nanocrystalline ferrites were synthesized through sol-gel method in different size distributions and the effect of finite size on magnetic properties is investigated. Results of magnetization and Mössbauer measurements show that superparamagnetism and weak ferromagnetic behavior in some of the size distributions. The origin of the superparamagnetism is from fine particles similar to ferromagnetic single domains and the weak ferromagnetism comes from surface spin disorder caused by Dzyaloshinskii-Moriya interaction. The magnetic ground state of LaFeO{sub 3} nanoparticles differs from that of bulk, and the ground state is dictated by the finite size effect because density of states depends on the dimensionality of the sample.

Sendil Kumar, A., E-mail: sendilphy@gmail.com, E-mail: anilb42@gmail.com [School of Physics, University of Hyderabad, Hyderabad, Telangana 500 046 (India); Manivel Raja, M. [Advanced Magnetics Group, Defence Metallurgical Research Laboratory, Hyderabad, Telangana 500 058 (India); Bhatnagar, Anil K., E-mail: sendilphy@gmail.com, E-mail: anilb42@gmail.com [School of Physics, University of Hyderabad, Hyderabad, Telangana 500 046 (India); School of Engineering Sciences and Technology, University of Hyderabad, Hyderabad, Telangana 500 046 (India)

2014-09-21T23:59:59.000Z

170

Effect of composition and heat treatment on MnBi magnetic materials  

SciTech Connect (OSTI)

The metallic compound MnBi is a promising rare-earth-free permanent magnet material, unique among all candidates for its high intrinsic coercivity (Hci) and its large positive temperature coefficient. The Hci of MnBi in thin-film or powder form can exceed 12 and 26 kOe at 300 and 523 K, respectively. Such a steep rise in Hci with increasing temperature is unique to MnBi. Consequently, MnBi is a highly sought-after hard phase for exchange coupling nanocomposite magnets. However, the reaction between Mn and Bi is peritectic, and hence Mn tends to precipitate out of the MnBi liquid during the solidification process. As result, when the alloy is prepared using conventional induction or arc-melting casting methods, additional Mn is required to compensate the precipitation of Mn. In addition to composition, post-casting annealing plays an important role in obtaining a high content of MnBi low-temperature phase (LTP) because the annealing encourages the Mn precipitates and the unreacted Bi to react, forming the desired LTP phase. Here we report a systematic study of the effect of composition and heat treatments on the phase content and magnetic properties of Mn–Bi alloys. In this study, 14 compositions were prepared using conventional metallurgical methods, and the compositions, crystal structures, phase content and magnetic properties of the resulting alloys were analyzed. The results show that the composition with 55 at.% Mn exhibits both the highest LTP content (93 wt.%) and magnetization (74 emu g?1 with 9 T applied field at 300 K).

Cui, Jun [Pacific Northwest National Laboratory; Choi, Jung-Pyung [Pacific Northwest National Laboratory; Polikarpov, Evgueni [Pacific Northwest National Laboratory; Bowden, Mark E [Pacific Northwest National Laboratory; Xie, Wei [Pacific Northwest National Laboratory; Li, Guosheng [Pacific Northwest National Laboratory; Nie, Zimin [Pacific Northwest National Laboratory; Zarkevich, Nikolai [Ames Laboratory; Kramer, Matthew J [Ames Laboratory; Johnson, Duane [Ames Laboratory

2014-10-01T23:59:59.000Z

171

Development of Advanced Wear and Corrosion Resistant Systems Through Laser Surface Alloying and Materials Simulations  

SciTech Connect (OSTI)

Laser surfacing in the form of cladding, alloying, and modifications are gaining widespread use because of its ability to provide high deposition rates, low thermal distortion, and refined microstructure due to high solidification rates. Because of these advantages, laser surface alloying is considered a prime candidate for producing ultra-hard coatings through the establishment or in situ formation of composite structures. Therefore, a program was conducted by the Applied Research Laboratory, Pennsylvania State University and Oak Ridge National Laboratory to develop the scientific and engineering basis for performing laser-based surface modifications involving the addition of hard particles, such as carbides, borides, and nitrides, within a metallic matrix for improved wear, fatigue, creep, and corrosion resistance. This has involved the development of advanced laser processing and simulation techniques, along with the refinement and application of these techniques for predicting and selecting materials and processing parameters for the creation of new surfaces having improved properties over current coating technologies. This program has also resulted in the formulation of process and material simulation tools capable of examining the potential for the formation and retention of composite coatings and deposits produced using laser processing techniques, as well as positive laboratory demonstrations in producing these coatings. In conjunction with the process simulation techniques, the application of computational thermodynamic and kinetic models to design laser surface alloying materials was demonstrated and resulted in a vast improvement in the formulation of materials used for producing composite coatings. The methodology was used to identify materials and to selectively modify microstructures for increasing hardness of deposits produced by the laser surface alloying process. Computational thermodynamic calculations indicated that it was possible to induce the precipitation of titanium carbonitrides during laser surface alloying provided there was sufficient amount of dissolved titanium, carbon, and nitrogen in the liquid steel. This was confirmed experimentally by using a powder mixture of 431-martensitic steel, titanium carbide powder, and nitrogen shielding, during laser deposition to produce deposits exhibiting relatively high hardness (average surface hardness of 724 HV). The same approach was extended to direct diode laser processing and similar microstructures were attained. The above analysis was extended to develop an in-situ precipitation of Ti(CN) during laser deposition. The Ti addition was achieving by mixing the 431 martensitic steel powders with ferro-titanium. The dissolution of nitrogen was achieved by using 100% nitrogen shielding gas, which was indicated by thermodynamic analysis. Demonstrations were also conducted utilizing the tools developed during the program and resulted in several viable composite coating systems being identified. This included the use of TiC and ferro-titanium in martensitic-grade stainless steel matrix material with and without the use of active N2 shielding gas, WC hard particles in a martensitic-grade stainless steel matrix material, WC and BN in a nickel-based matrix material, and WC in highly alloyed iron-based matrix. Although these demonstrations indicated the potential of forming composite coatings, in certain instances, the intended industrial applications involved unique requirements, such as coating of internal surfaces, which hindered the full development of the improved coating technology. However, it is believed that the addition of common hard particles, such as WC or TiC, to matrix material representing martensitic grades of stainless steel offer opportunities for improved performance at relatively low material cost.

R. P. Martukanitz and S. Babu

2007-05-03T23:59:59.000Z

172

Final Report: Stability and Novel Properties of Magnetic Materials and Ferromagnet / Insulator Interfaces  

SciTech Connect (OSTI)

We report investigations of the synthesis, structure, and properties of new materials for spintronic applications integrated onto silicon substrates. Our primary focus is materials with very high, negative, intrinsic spin polarization of the density of states at the Fermi level. We have developed a new synthesis method for Fe3O4 thin films through selective oxidation of Fe, resulting in smooth, low-defect density films. We have synthesized Fe4N films and shown that they preferentially oxidize to Fe3O4. When integrated into magnetic tunnel junctions consisting of Fe4N / AlOx / Fe, oxidation at the Fe4N / AlOx interface creates Fe3O4, leading to negative tunneling magnetoresistance (TMR). Oxidation of Fe in nominally symmetric CoFe / AlOx / CoFe also produces Fe3O4 and negative TMR under selected oxidation conditions.

Voyles, Paul [University of Wisconsin, Madison] [University of Wisconsin, Madison

2013-07-24T23:59:59.000Z

173

Laser Measurement of SAM Bulk and Surface Wave Amplitudes for Material Microstructure Analysis  

SciTech Connect (OSTI)

Scanning Acoustic Microscopy (SAM) at ultra high frequencies has proven to be a useful tool for investigating materials on the scale of individual grains. This technique is normally performed in a reflection mode from one side of a sample surface. Information about the generation and transmission of bulk acoustic waves into the material is inferred from the reflection signal amplitude. We present an adaptation to the SAM method whereby the acoustic bulk waves are directly visualized through laser acoustic detection. Ultrasonic waves were emitted from a nominal 200 MHz point focus acoustic lens into a thin silicon plate (thickness 75ìm) coupled with distilled water. A scanned laser beam detected the bulk and surface acoustic waves at the opposite surface of the thin silicon plate. Distinct amplitude patterns exhibiting the expected symmetry for Silicon were observed that alter in predictable ways as the acoustic focal point was moved throughout the plate. Predictions of the acoustic wave fields generated by the acoustic lens within and at the surface of the Silicon are being investigated through the angular spectrum of plane waves approach. Results shall be presented for plates with (100) and (111) orientations followed by discussion of applications of the technique for material microstructure analysis.

Ken L. Telschow; Chiaki Miyasaka; David L. Cottle

2005-07-01T23:59:59.000Z

174

Magnetic resonance imaging (MRI) of solid materials entails numerous problems from short longitudinal relaxation (T2) times to  

E-Print Network [OSTI]

. Solid-State STRAFI NMR Probe for Material Imaging of Quadrupolar Nuclei, J. Magn. Reson. httpMagnetic resonance imaging (MRI) of solid materials entails numerous problems from short for broadband tuning, sample translation along z-axis, and electrodes for in situ battery studies. An Alderman

Weston, Ken

175

Sub-surface characterization and three dimensional profiling of semiconductors by magnetic resonance force microscopy  

SciTech Connect (OSTI)

This is the final report of a two-year, Laboratory-Directed Research and Development (LDRD) project at the Los Alamos National Laboratory (LANL). The project successfully developed a magnetic resonance force microscope (MRFM) instrument to mechanically detect magnetic resonance signals. This technique provides an intrinsically subsurface, chemical-species-specific probe of structure, constituent density and other properties of materials. As in conventional magnetic resonance imaging (MRI), an applied magnetic field gradient selects a well defined volume of the sample for study. However mechanical detection allows much greater sensitivity, and this in turn allows the reduction of the size of the minimum resolvable volume. This requires building an instrument designed to achieve nanometer-scale resolution at buried semiconductor interfaces. High-resolution, three-dimensional depth profiling of semiconductors is critical in the development and fabrication of semiconductor devices. Currently, there is no capability for direct, high-resolution observation and characterization of dopant density, and other critical features of semiconductors. The successful development of MRFM in conjunction with modifications to improve resolution will enable for the first time detailed structural and electronic studies in doped semiconductors and multilayered nanoelectronic devices, greatly accelerating the current pace of research and development.

Hammel, P.C.; Moore, G.; Roukes, M.; Zhenyong Zhang

1996-10-01T23:59:59.000Z

176

Solar-wind protons and heavy ions sputtering of lunar surface materials A.F. Barghouty a,  

E-Print Network [OSTI]

Solar-wind protons and heavy ions sputtering of lunar surface materials A.F. Barghouty a, , F Available online 21 December 2010 Keywords: Solar wind sputtering Lunar regolith KREEP soil Potential a c t Lunar surface materials are exposed to $1 keV/amu solar-wind protons and heavy ions on almost

177

Effect of ion excape velocity and conversion surface material on H- production  

SciTech Connect (OSTI)

According to generally accepted models surface production of negative ions depends on ion escape velocity and work function of the surface. We have conducted an experimental study addressing the role of the ion escape velocity on H{sup -} production. A converter-type ion source at Los Alamos Neutron Science Center was employed for the experiment. The ion escape velocity was changed by varying the bias voltage of the converter electrode. It was observed that due to enhanced stripping of H{sup -} no direct gain of extracted beam current can be achieved by increasing the converter voltage. At the same time the conversion efficiency of H{sup -} was observed to vary with converter voltage and follow the existing theories in qualitative manner. We discuss the role of surface material on H{sup -} formation probability and present calculations predicting relative H{sup -} yields from different cesiated surfaces. These calculations are compared with experimental observations from different types of H{sup -} ion sources. The effects caused by varying cesium coverage are also discussed. Finally, we present a novel idea of utilizing materials exhibiting so-called negative electron affinity in H{sup -}/D{sup -} production under UV-light exposure.

Johnson, Kenneth F [Los Alamos National Laboratory; Tarvainen, Olli A [Los Alamos National Laboratory; Geros, E. [Los Alamos National Laboratory; Stelzer, J. [Los Alamos National Laboratory; Rouleau, G. [Los Alamos National Laboratory; Kalvas, T. [UNIV OF JYVASKYLA; Komppula, J. [UNIV OF JYASKYLA; Carmichael, J. [ORNL

2010-10-05T23:59:59.000Z

178

Imaging the early material response associated with exit surface damage in fused silica  

SciTech Connect (OSTI)

The processes involved at the onset of damage initiation on the surface of fused silica have been a topic of extensive discussion and thought for more than four decades. Limited experimental results have helped develop models covering specific aspects of the process. In this work we present the results of an experimental study aiming at imaging the material response from the onset of the observation of material modification during exposure to the laser pulse through the time point at which material ejection begins. The system involves damage initiation using a 355 nm pulse, 7.8 ns FWHM in duration and imaging of the affected material volume with spatial resolution on the order of 1 {micro}m using as strobe light a 150 ps laser pulse that is appropriately timed with respect to the pump pulse. The observations reveal that the onset of material modification is associated with regions of increased absorption, i.e., formation of an electronic excitation, leading to a reduction in the probe transmission to only a few percent within a time interval of about 1 ns. This area is subsequently rapidly expanding with a speed of about 1.2 {micro}m/ns and is accompanied by the formation and propagation of radial cracks. These cracks appear to initiate about 2 ns after the start of the expansion of the modified region. The damage sites continue to grow for about 25 ns but the mechanism of expansion after the termination of the laser pulse is via formation and propagation of lateral cracks. During this time, the affected area of the surface appears to expand forming a bulge of about 40 {micro}m in height. The first clear observation of material cluster ejection is noted at about 50 ns delay.

Demos, S G; Raman, R N; Negres, R A

2010-11-05T23:59:59.000Z

179

Development of Apple Workgroup Cluster and Parallel Computing for Phase Field Model of Magnetic Materials  

E-Print Network [OSTI]

Micromagnetic modeling numerically solves magnetization evolution equation to process magnetic domain analysis, which helps to understand the macroscopic magnetic properties of ferromagnets. To apply this method in simulation of magnetostrictive...

Huang, Yongxin

2010-01-16T23:59:59.000Z

180

Rare?Earth?Free Permanent Magnets for Electrical Vehicle Motors and Wind Turbine Generators: Hexagonal Symmetry Based Materials Systems Mn?Bi and M?type Hexaferrite  

SciTech Connect (OSTI)

The research we conducted focuses on the rare-earth (RE)-free permanent magnet by modeling, simulating, and synthesizing exchange coupled two-phase (hard/soft) RE-free core-shell nano-structured magnet. The RE-free magnets are made of magnetically hard core materials (high anisotropy materials including Mn-Bi-X and M-type hexaferrite) coated by soft shell materials (high magnetization materials including Fe-Co or Co). Therefore, our research helps understand the exchange coupling conditions of the core/shell magnets, interface exchange behavior between core and shell materials, formation mechanism of core/shell structures, stability conditions of core and shell materials, etc.

Hong, Yang-Ki [University of Alabama] [University of Alabama; Haskew, Timothy [University of Alabama] [University of Alabama; Myryasov, Oleg [University of Alabama] [University of Alabama; Jin, Sungho [University of California San Diego] [University of California San Diego; Berkowitz, Ami [University of California San Diego] [University of California San Diego

2014-06-05T23:59:59.000Z

Note: This page contains sample records for the topic "magnetism materials surface" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


181

Investigation of anisotropic photonic band gaps in three-dimensional magnetized plasma photonic crystals containing the uniaxial material  

SciTech Connect (OSTI)

In this paper, the dispersive properties of three-dimensional (3D) magnetized plasma photonic crystals (MPPCs) composed of anisotropic dielectric (the uniaxial material) spheres immersed in homogeneous magnetized plasma background with face-centered-cubic (fcc) lattices are theoretically investigated by the plane wave expansion method, as the Voigt effects of magnetized plasma are considered. The equations for calculating the anisotropic photonic band gaps (PBGs) in the first irreducible Brillouin zone are theoretically deduced. The anisotropic PBGs and two flatbands regions can be obtained. The effects of the ordinary-refractive index, extraordinary-refractive index, filling factor, plasma frequency, and external magnetic field on the dispersive properties of the 3D MPPCs are investigated in detail, respectively, and some corresponding physical explanations are also given. The numerical results show that the anisotropy can open partial band gaps in 3D MPPCs with fcc lattices and the complete PBGs can be found compared to the conventional 3D MPPCs doped by the isotropic material. The bandwidths of PBGs can be tuned by introducing the magnetized plasma into 3D PCs containing the uniaxial material. It is also shown that the anisotropic PBGs can be manipulated by the ordinary-refractive index, extraordinary-refractive index, filling factor, plasma frequency, and external magnetic field, respectively. The locations of flatbands regions cannot be manipulated by any parameters except for the plasma frequency and external magnetic field. Introducing the uniaxial material can obtain the complete PBGs as the 3D MPPCs with high symmetry and also provides a way to design the tunable devices.

Zhang, Hai-Feng [College of Electronic and Information Engineering, Nanjing University of Aeronautics and Astronautics, Nanjing 210016 (China) [College of Electronic and Information Engineering, Nanjing University of Aeronautics and Astronautics, Nanjing 210016 (China); Nanjing Artillery Academy, Nanjing 211132 (China)] [China; Liu, Shao-Bin; Kong, Xiang-Kun [College of Electronic and Information Engineering, Nanjing University of Aeronautics and Astronautics, Nanjing 210016 (China)] [College of Electronic and Information Engineering, Nanjing University of Aeronautics and Astronautics, Nanjing 210016 (China)

2013-09-15T23:59:59.000Z

182

Magnetic fusion energy plasma interactive and high heat flux components. Volume I. Technical assessment of the critical issues and problem areas in the plasma materials interaction field  

SciTech Connect (OSTI)

A technical assessment of the critical issues and problem areas in the field of plasma materials interactions (PMI) in magnetic fusion devices shows these problems to be central for near-term experiments, for intermediate-range reactor devices including D-T burning physics experiments, and for long-term reactor machines. Critical technical issues are ones central to understanding and successful operation of existing and near-term experiments/reactors or devices of great importance for the long run, i.e., ones which will require an extensive, long-term development effort and thus should receive attention now. Four subgroups were formed to assess the critical PMI issues along four major lines: (1) PMI and plasma confinement physics experiments; (2) plasma-edge modelling and theory; (3) surface physics; and (4) materials technology for in-vessel components and the first wall. The report which follows is divided into four major sections, one for each of these topics.

Conn, R.W.; Gauster, W.B.; Heifetz, D.; Marmar, E.; Wilson, K.L. (eds.)

1984-01-01T23:59:59.000Z

183

Magnetic infrasound sensor  

DOE Patents [OSTI]

A magnetic infrasound sensor is produced by constraining a permanent magnet inside a magnetic potential well above the surface of superconducting material. The magnetic infrasound sensor measures the position or movement of the permanent magnet within the magnetic potential well, and interprets the measurements. Infrasound sources can be located and characterized by combining the measurements from one or more infrasound sensors. The magnetic infrasound sensor can be tuned to match infrasound source types, resulting in better signal-to-noise ratio. The present invention can operate in frequency modulation mode to improve sensitivity and signal-to-noise ratio. In an alternate construction, the superconductor can be levitated over a magnet or magnets. The system can also be driven, so that time resolved perturbations are sensed, resulting in a frequency modulation version with improved sensitivity and signal-to-noise ratio.

Mueller, Fred M. (Los Alamos, NM); Bronisz, Lawrence (Los Alamos, NM); Grube, Holger (Los Alamos, NM); Nelson, David C. (Santa Fe, NM); Mace, Jonathan L. (Los Alamos, NM)

2006-11-14T23:59:59.000Z

184

Mesoporous Co{sub 3}O{sub 4} nanostructured material synthesized by one-step soft-templating: A magnetic study  

SciTech Connect (OSTI)

A combined magnetization and zero-field {sup 59}Co spin-echo nuclear magnetic resonance (NMR) study has been carried out on one member of a recently developed class of highly ordered mesoporous nanostructured materials, mesoporous Co{sub 3}O{sub 4} (designated UCT-8, University of Connecticut, mesoporous materials). The material was synthesized using one-step soft-templating by an inverse micelles packing approach. Characterization of UCT-8 by powder x-ray diffraction and electron microscopy reveals that the mesostructure consists of random close-packed Co{sub 3}O{sub 4} nanoparticles ??12?nm in diameter. The N{sub 2} sorption isotherm for UCT-8, which is type IV with a type H1 hysteresis loop, yields a 134 m{sup 2}/g BET surface area and a 7.7?nm BJH desorption pore diameter. The effect of heat treatment on the structure is discussed. The antiferromagnetic Co{sub 3}O{sub 4} nanoparticles have a Néel temperature T{sub N}?=?27?K, somewhat lower than the bulk. A fit to the Curie-Weiss law over the temperature range 75?K???T???300?K yields an effective magnetic moment of ?{sub eff}?=?4.36??{sub B} for the Co{sup 2+} ions, indicative of some orbital contribution, and a Curie-Weiss temperature ??=??93.5?K, consistent with antiferromagnetic ordering. The inter-sublattice and intra-sublattice exchange constants for the Co{sup 2+} ions are J{sub 1}/k{sub B}?=?(?)4.75?K and J{sub 2}/k{sub B}?=?(?)0.87?K, respectively, both corresponding to antiferromagnetic coupling. The presence of uncompensated surface spins is observed below T{sub N} with shifts in the hysteresis loops, i.e., an exchange-bias effect. The {sup 59}Co NMR spectrum for UCT-8, which is attributed to Co{sup 2+} ions at the tetrahedral A sites, is asymmetrically broadened with a peak at ?55?MHz (T?=?4.2?K). Since there is cubic symmetry at the A-sites, the broadening is indicative of a magnetic field distribution due to the uncompensated surface spins. The spectrum is consistent with antiferromagnetically ordered particles that are nanometer in size and single domain.

Poyraz, Altug S.; Kuo, Chung-Hao; Li, Nan [Department of Chemistry, University of Connecticut, Storrs, Connecticut 06269-3060 (United States); Hines, William A., E-mail: wahines@phys.uconn.edu; Perry, David M. [Department of Physics, University of Connecticut, Storrs, Connecticut 06269-3046 (United States); Suib, Steven L. [Department of Chemistry, University of Connecticut, Storrs, Connecticut 06269-3060 (United States); Institute of Materials Science, University of Connecticut, Storrs, Connecticut 06269-3136 (United States)

2014-03-21T23:59:59.000Z

185

A Study to Verify the Material Surface Concept of Water Table by Examining Analytical and Numerical Models.  

E-Print Network [OSTI]

The highly nonlinear nature of unsaturated flow results in different ways to approximate the delayed or instantaneous movement of the water table. In nearly all the approaches, the water table is conceptually treated as a “material surface...

Dadi, Sireesh Kumar

2011-10-21T23:59:59.000Z

186

Maximizing Hysteretic Losses in Magnetic Ferrite Nanoparticles via Model-Driven Synthesis and Materials Optimization  

E-Print Network [OSTI]

This article develops a set of design guidelines for maximizing heat dissipation characteristics of magnetic ferrite MFe[subscript 2]O[subscript 4] (M = Mn, Fe, Co) nanoparticles in alternating magnetic fields. Using ...

Chen, Ritchie

187

A Review of Removable Surface Contamination on Radioactive Materials Transportation Containers  

SciTech Connect (OSTI)

This report contains the results of a study sponsored by the U.S. Nuclear Regulatory Commission (NRC) of removable surface contamination on radioactive materials transportation containers. The purpose of the study is to provide information to the NRC during their review of existing regulations. Data was obtained from both industry and literature on three major topics: 1) radiation doses, 2) economic costs, and 3) contamination frequencies. Containers for four categories of radioactive materials are considered including radiopharmaceuticals, industrial sources, nuclear fuel cycle materials, and low-level radioactive waste. Assumptions made in this study use current information to obtain realistic yet conservative estimates of radiation dose and economic costs. Collective and individual radiation doses are presented for each container category on a per container basis. Total doses, to workers and the public, are also presented for spent fuel cask and low-level waste drum decontamination. Estimates of the additional economic costs incurred by lowering current limits by factors of 10 and 100 are presented. Current contamination levels for each category of container are estimated from the data collected. The information contained in this report is designed to be useful to the NRC in preparing their recommendations for new regulations.

Kennedy, Jr, W. E.; Watson, E. C.; Murphy, D. W.; Harrer, B. J.; Harty, R.; Aldrich, J. M.

1981-05-01T23:59:59.000Z

188

Thermal and high magnetic field treatment of materials and associated apparatus  

DOE Patents [OSTI]

An apparatus and method for altering characteristics, such as can include structural, magnetic, electrical, optical or acoustical characteristics, of an electrically-conductive workpiece utilizes a magnetic field within which the workpiece is positionable and schemes for thermally treating the workpiece by heating or cooling techniques in conjunction with the generated magnetic field so that the characteristics of the workpiece are effected by both the generated magnetic field and the thermal treatment of the workpiece.

Kisner, Roger A.; Wilgen, John B.; Ludtka, Gerard M.; Jaramillo, Roger A.; Mackiewicz-Ludtka, Gail

2010-06-29T23:59:59.000Z

189

Thermal and high magnetic field treatment of materials and associated apparatus  

DOE Patents [OSTI]

An apparatus and method for altering characteristics, such as can include structural, magnetic, electrical, optical or acoustical characteristics, of an electrically-conductive workpiece utilizes a magnetic field within which the workpiece is positionable and schemes for thermally treating the workpiece by heating or cooling techniques in conjunction with the generated magnetic field so that the characteristics of the workpiece are effected by both the generated magnetic field and the thermal treatment of the workpiece.

Kisner, Roger A.; Wilgen, John B.; Ludtka, Gerard M.; Jaramillo, Roger A.; Mackiewicz-Ludtka, Gail

2007-01-09T23:59:59.000Z

190

Theoretical Modelling of Magnetic Refrigeration Materials A PhD studentship is available in the Warwick Theory Group on a theoretical/computational PhD project  

E-Print Network [OSTI]

materials. The project will involve condensed matter physics theory, high performance computingTheoretical Modelling of Magnetic Refrigeration Materials A PhD studentship is available in the Warwick Theory Group on a theoretical/computational PhD project on the modelling of magnetic refrigeration

Low, Robert

191

Characterization of proton exchange membrane materials for fuel cells by solid state nuclear magnetic resonance  

SciTech Connect (OSTI)

Solid-state nuclear magnetic resonance (NMR) has been used to explore the nanometer-scale structure of Nafion, the widely used fuel cell membrane, and its composites. We have shown that solid-state NMR can characterize chemical structure and composition, domain size and morphology, internuclear distances, molecular dynamics, etc. The newly-developed water channel model of Nafion has been confirmed, and important characteristic length-scales established. Nafion-based organic and inorganic composites with special properties have also been characterized and their structures elucidated. The morphology of Nafion varies with hydration level, and is reflected in the changes in surface-to-volume (S/V) ratio of the polymer obtained by small-angle X-ray scattering (SAXS). The S/V ratios of different Nafion models have been evaluated numerically. It has been found that only the water channel model gives the measured S/V ratios in the normal hydration range of a working fuel cell, while dispersed water molecules and polymer ribbons account for the structures at low and high hydration levels, respectively.

Kong, Zueqian

2010-03-15T23:59:59.000Z

192

Development of Superconducting Materials for Use in Magnet Applications: Nb3Sn Flux Pinning and Bi-2212 Magnetic Texturing  

E-Print Network [OSTI]

as round wires are presented and discussed. Processes were developed to increase flux pinning in Nb3Sn by utilizing powder metallurgy techniques to introduce a heterogeneously homogenous distribution of nanoscale inclusions of candidate materials in Nb rod...

Rahmani, David G.

2010-07-14T23:59:59.000Z

193

Corrosion in Supercritical carbon Dioxide: Materials, Environmental Purity, Surface Treatments, and Flow Issues  

SciTech Connect (OSTI)

The supercritical CO{sub 2} Brayton cycle is gaining importance for power conversion in the Generation IV fast reactor system because of its high conversion efficiencies. When used in conjunction with a sodium fast reactor, the supercritical CO{sub 2} cycle offers additional safety advantages by eliminating potential sodium-water interactions that may occur in a steam cycle. In power conversion systems for Generation IV fast reactors, supercritical CO{sub 2} temperatures could be in the range of 30°C to 650°C, depending on the specific component in the system. Materials corrosion primarily at high temperatures will be an important issue. Therefore, the corrosion performance limits for materials at various temperatures must be established. The proposed research will have four objectives centered on addressing corrosion issues in a high-temperature supercritical CO{sub 2} environment: Task 1: Evaluation of corrosion performance of candidate alloys in high-purity supercritical CO{sub 2}: The following alloys will be tested: Ferritic-martensitic Steels NF616 and HCM12A, austenitic alloys Incoloy 800H and 347 stainless steel, and two advanced concept alloys, AFA (alumina forming austenitic) steel and MA754. Supercritical CO{sub 2} testing will be performed at 450°C, 550°C, and 650°C at a pressure of 20 MPa, in a test facility that is already in place at the proposing university. High purity CO{sub 2} (99.9998%) will be used for these tests. Task 2: Investigation of the effects of CO, H{sub 2}O, and O{sub 2} impurities in supercritical CO{sub 2} on corrosion: Impurities that will inevitably present in the CO{sub 2} will play a critical role in dictating the extent of corrosion and corrosion mechanisms. These effects must be understood to identify the level of CO{sub 2} chemistry control needed to maintain sufficient levels of purity to manage corrosion. The individual effects of important impurities CO, H{sub 2}O, and O{sub 2} will be investigated by adding them separately to high purity CO{sub 2}. Task 3: Evaluation of surface treatments on the corrosion performance of alloys in supercritical CO{sub 2}: Surface treatments can be very beneficial in improving corrosion resistance. Shot peening and yttrium and aluminum surface treatments will be investigated. Shot peening refines the surface grain sizes and promotes protective Cr-oxide layer formation. Both yttrium and aluminum form highly stable oxide layers (Y{sub 2}O{sub 3} and Al{sub 2}O{sub 3}), which can get incorporated in the growing Fe-oxide layer to form an impervious complex oxide to enhance corrosion resistance. Task 4: Study of flow-assisted corrosion of select alloys in supercritical CO{sub 2} under a selected set of test conditions: To study the effects of flow-assisted corrosion, tests will be conducted in a supercritical CO{sub 2} flow loop. An existing facility used for supercritical water flow studies at the proposing university will be modified for use in this task. The system is capable of flow velocities up to 10 m/s and can operate at temperatures and pressures of up to 650°C and 20 MPa, respectively. All above tasks will be performed in conjunction with detailed materials characterization and analysis using scanning electron microscopy/energy dispersive spectroscopy (SEM-EDS), x-ray diffraction (XRD), Auger electron spectroscopy (AES) techniques, and weight change measurements. Inlet and outlet gas compositions will be monitored using gas chromatography-mass spectrometry (GCMS).

Sridharan, Kumar; Anderson, Mark

2013-12-10T23:59:59.000Z

194

ASTM standards for measuring solar reflectance and infrared emittance of construction materials and comparing their steady-state surface temperatures  

SciTech Connect (OSTI)

Numerous experiments on individual buildings in California and Florida show that painting roofs white reduces air conditioning load up to 50%, depending on the thermal resistance or amount of insulation under the roof. The savings, of course, are strong functions of the thermal integrity of a building and climate. In earlier work, the authors have estimated the national energy savings potential from reflective roofs and paved surfaces. Achieving this potential, however, is conditional on receiving the necessary Federal, states, and electric utilities support to develop materials with high solar reflectance and design effective implementation programs. An important step in initiating an effective program in this area is to work with the american Society for Testing and Materials (ASTM) and the industry to create test procedures, rating, and labeling for building and paving materials. A subcommittee of ASTM E06, E06.42, on Cool Construction Materials, was formed as the vehicle to develop standard practices for measuring, rating, and labeling cool construction materials. The subcommittee has also undertaken the development of a standard practice for calculating a solar reflectance index (SRI) of horizontal and low-sloped surfaces. SRI is a measure of the relative steady-state temperature of a surface with respect to a standard white surface (SRI = 100) and a standard black surface (SRI = 0) under standard solar and ambient conditions. This paper discusses the technical issues relating to development of these two ASTM standards.

Akbari, H.; Levinson, R.; Berdahl, P. [Lawrence Berkeley National Lab., CA (United States). Energy and Environment Div.

1996-08-01T23:59:59.000Z

195

Investigation of IAQ-Relevant Surface Chemistry and Emissions on HVAC Filter Materials  

E-Print Network [OSTI]

VOCs emitted by reactions of HVAC filters with ozone usingChemistry and Emissions on HVAC Filter Materials HugoChemistry and Emissions on HVAC Filter Materials Authors:

Destaillats, Hugo

2010-01-01T23:59:59.000Z

196

Final Report: MATERIALS, STRANDS, AND CABLES FOR SUPERCONDUCTING ACCELERATOR MAGNETS [Grant Number DE-SC0010312  

SciTech Connect (OSTI)

Our program consisted of the two components: Strand Research and Cable Research, with a focus on Nb3Sn, Bi2212, and YBCO for accelerator magnet applications. We demonstrated a method to refine the grains in Nb3Sn by a factor of two, reaching 45 nm grain sizes, and layer Jcs of 6 kA/mm2 at 12 T. W also measured conductor magnetization for field quality. This has been done both with Nb3Sn conductor, as well as Bi:2212 strand. Work in support of quench studies of YBCO coils was also performed. Cable loss studies in Nb3Sn focused on connecting and comparing persistent magnetization and coupling magnetization for considering their relative impact on HEP machines. In the area of HTS cables, we have investigated both the quench in multistrand YBCO CORC cables, as well as the magnetization of these cables for use in high field magnets. In addition, we examined the magnetic and thermal properties of large (50 T) solenoids.

Sumption, Mike; Collings, E.

2014-10-29T23:59:59.000Z

197

Active magnetic refrigerants based on Gd-Si-Ge material and refrigeration apparatus and process  

DOE Patents [OSTI]

Active magnetic regenerator and method using Gd.sub.5 (Si.sub.x Ge.sub.1-x).sub.4, where x is equal to or less than 0.5, as a magnetic refrigerant that exhibits a reversible ferromagnetic/antiferromagnetic or ferromagnetic-II/ferromagnetic-I first order phase transition and extraordinary magneto-thermal properties, such as a giant magnetocaloric effect, that renders the refrigerant more efficient and useful than existing magnetic refrigerants for commercialization of magnetic regenerators. The reversible first order phase transition is tunable from approximately 30 K to approximately 290 K (near room temperature) and above by compositional adjustments. The active magnetic regenerator and method can function for refrigerating, air conditioning, and liquefying low temperature cryogens with significantly improved efficiency and operating temperature range from approximately 10 K to 300 K and above. Also an active magnetic regenerator and method using Gd.sub.5 (Si.sub.x Ge.sub.1-x).sub.4, where x is equal to or greater than 0.5, as a magnetic heater/refrigerant that exhibits a reversible ferromagnetic/paramagnetic second order phase transition with large magneto-thermal properties, such as a large magnetocaloric effect that permits the commercialization of a magnetic heat pump and/or refrigerant. This second order phase transition is tunable from approximately 280 K (near room temperature) to approximately 350 K by composition adjustments. The active magnetic regenerator and method can function for low level heating for climate control for buildings, homes and automobile, and chemical processing.

Gschneidner, Jr., Karl A. (Ames, IA); Pecharsky, Vitalij K. (Ames, IA)

1998-04-28T23:59:59.000Z

198

Active magnetic refrigerants based on Gd-Si-Ge material and refrigeration apparatus and process  

DOE Patents [OSTI]

Active magnetic regenerator and method using Gd{sub 5} (Si{sub x}Ge{sub 1{minus}x}){sub 4}, where x is equal to or less than 0.5, as a magnetic refrigerant that exhibits a reversible ferromagnetic/antiferromagnetic or ferromagnetic-II/ferromagnetic-I first order phase transition and extraordinary magneto-thermal properties, such as a giant magnetocaloric effect, that renders the refrigerant more efficient and useful than existing magnetic refrigerants for commercialization of magnetic regenerators. The reversible first order phase transition is tunable from approximately 30 K to approximately 290 K (near room temperature) and above by compositional adjustments. The active magnetic regenerator and method can function for refrigerating, air conditioning, and liquefying low temperature cryogens with significantly improved efficiency and operating temperature range from approximately 10 K to 300 K and above. Also an active magnetic regenerator and method using Gd{sub 5} (Si{sub x} Ge{sub 1{minus}x}){sub 4}, where x is equal to or greater than 0.5, as a magnetic heater/refrigerant that exhibits a reversible ferromagnetic/paramagnetic second order phase transition with large magneto-thermal properties, such as a large magnetocaloric effect that permits the commercialization of a magnetic heat pump and/or refrigerant. This second order phase transition is tunable from approximately 280 K (near room temperature) to approximately 350 K by composition adjustments. The active magnetic regenerator and method can function for low level heating for climate control for buildings, homes and automobile, and chemical processing. 27 figs.

Gschneidner, K.A. Jr.; Pecharsky, V.K.

1998-04-28T23:59:59.000Z

199

Permanent magnet multipole with adjustable strength  

DOE Patents [OSTI]

Two or more magnetically soft pole pieces are symmetrically positioned along a longitudinal axis to provide a magnetic field within a space defined by the pole pieces. Two or more permanent magnets are mounted to an external magnetically-soft cylindrical sleeve which rotates to bring the permanent magnets into closer coupling with the pole pieces and thereby adjustably control the field strength of the magnetic field produced in the space defined by the pole pieces. The permanent magnets are preferably formed of rare earth cobalt (REC) material which has a high remanent magnetic field and a strong coercive force. The pole pieces and the permanent magnets have corresponding cylindrical surfaces which are positionable with respect to each other to vary the coupling therebetween. Auxiliary permanent magnets are provided between the pole pieces to provide additional magnetic flux to the magnetic field without saturating the pole pieces.

Halbach, Klaus (Berkeley, CA)

1985-01-01T23:59:59.000Z

200

Permanent-magnet multipole with adjustable strength  

DOE Patents [OSTI]

Two or more magnetically soft pole pieces are symmetrically positioned along a longitudinal axis to provide a magnetic field within a space defined by the pole pieces. Two or more permanent magnets are mounted to an external magnetically-soft cylindrical sleeve which rotates to bring the permanent magnets into closer coupling with the pole pieces and thereby adjustably control the field strength of the magnetic field produced in the space defined by the pole pieces. The permanent magnets are preferably formed of rare earth cobalt (REC) material which has a high remanent magnetic field and a strong coercive force. The pole pieces and the permanent magnets have corresponding cylindrical surfaces which are positionable with respect to each other to vary the coupling there between. Auxiliary permanent magnets are provided between the pole pieces to provide additional magnetic flux to the magnetic field without saturating the pole pieces.

Halbach, K.

1982-09-20T23:59:59.000Z

Note: This page contains sample records for the topic "magnetism materials surface" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


201

Manganese Doping of Magnetic Iron Oxide Nanoparticles: Tailoring Surface Reactivity for a Regenerable Heavy Metal Sorbent  

SciTech Connect (OSTI)

A method for tuning the analyte affinity of magnetic, inorganic nanostructured sorbents for heavy metal contaminants is described. The manganese-doped iron oxide nanoparticle sorbents have a remarkably high affinity compared to the precursor material. Sorbent affinity can be tuned toward an analyte of interest simply by adjustment of the dopant quantity. The results show that following the Mn doping process there is a large increase in affinity and capacity for heavy metals (i.e., Co, Ni, Zn, As, Ag, Cd, Hg, and Tl). Capacity measurements were carried out for the removal of cadmium from river water and showed significantly higher loading than the relevant commercial sorbents tested for comparison. The reduction in Cd concentration from 100 ppb spiked river water to 1 ppb (less than the EPA drinking water limit of 5 ppb for Cd) was achieved following treatment with the Mn-doped iron oxide nanoparticles. The Mn-doped iron oxide nanoparticles were able to load 1 ppm of Cd followed by complete stripping and recovery of the Cd with a mild acid wash. The Cd loading and stripping is shown to be consistent through multiple cycles with no loss of sorbent performance.

Warner, Cynthia L.; Chouyyok, Wilaiwan; Mackie, Katherine E.; Neiner, Doinita; Saraf, Laxmikant; Droubay, Timothy C.; Warner, Marvin G.; Addleman, Raymond S.

2012-02-28T23:59:59.000Z

202

Imaging System to Measure Kinetics of Material Cluster Ejection During Exit-Surface Damage Initiation and Growth in Fused Silica  

SciTech Connect (OSTI)

Laser-induced damage on the surface of optical components typically is manifested by the formation of microscopic craters that can ultimately degrade the optics performance characteristics. It is believed that the damage process is the result of the material exposure to high temperatures and pressures within a volume on the order of several cubic microns located just below the surface. The response of the material following initial localized energy deposition by the laser pulse, including the timeline of events and the individual processes involved during this timeline, is still largely unknown. In this work we introduce a time-resolved microscope system designed to enable a detailed investigation of the sequence of dynamic events involved during surface damage. To best capture individual aspects of the damage timeline, this system is employed in multiple imaging configurations (such as multi-view image acquisition at a single time point and multi-image acquisition at different time points of the same event) and offers sensitivity to phenomena at very early delay times. The capabilities of this system are demonstrated with preliminary results from the study of exit-surface damage in fused silica. The time-resolved images provide information on the material response immediately following laser energy deposition, the processes later involved during crater formation or growth, the material ejecta kinetics, and overall material motion and transformation. Such results offer insight into the mechanisms governing damage initiation and growth in the optical components of ICF class laser systems.

Raman, R N; Negres, R A; Demos, S G

2009-10-29T23:59:59.000Z

203

Study of Interfacial Interactions Using Thing Film Surface Modification: Radiation and Oxidation Effects in Materials  

SciTech Connect (OSTI)

Interfaces play a key role in dictating the long-term stability of materials under the influence of radiation and high temperatures. For example, grain boundaries affect corrosion by way of providing kinetically favorable paths for elemental diffusion, but they can also act as sinks for defects and helium generated during irradiation. Likewise, the retention of high-temperature strength in nanostructured, oxide-dispersion strengthened steels depends strongly on the stoichiometric and physical stability of the (Y, Ti)-oxide particles/matrix interface under radiation and high temperatures. An understanding of these interfacial effects at a fundamental level is important for the development of materials for extreme environments of nuclear reactors. The goal of this project is to develop an understanding stability of interfaces by depositing thin films of materials on substrates followed by ion irradiation of the film-substrate system at elevated temperatures followed by post-irradiation oxidation treatments. Specifically, the research will be performed by depositing thin films of yttrium and titanium (~500 nm) on Fe-12%Cr binary alloy substrate. Y and Ti have been selected as thin-film materials because they form highly stable protective oxides layers. The Fe-12%Cr binary alloy has been selected because it is representative of ferritic steels that are widely used in nuclear systems. The absence of other alloying elements in this binary alloy would allow for a clearer examination of structures and compositions that evolve during high-temperature irradiations and oxidation treatments. The research is divided into four specific tasks: (1) sputter deposition of 500 nm thick films of Y and Ti on Fe-12%Cr alloy substrates, (2) ion irradiation of the film-substrate system with 2MeV protons to a dose of 2 dpa at temperatures of 300°C, 500°C, and 700°C, (3) oxidation of as-deposited and ion-irradiated samples in a controlled oxygen environment at 500°C and 700°C, (4) multi-scale computational modeling involving first- principle molecular dynamics (FPMD) and coarse-grained dissipative particle dynamics (DPD) approaches to develop theories underlying the evolution and stability of structures and phases. Samples from Tasks 1 to 3 (above) will be rigorously characterized and analyzed using scanning electron microscopy, Auger electron microscopy, x-ray diffraction, Rutherford back scatter spectroscopy, and transmission electron microscopy. Expected outcomes of the experimental work include a quantitative understanding film-substrate interface mixing, evolution of defects and other phases at the interface, interaction of interfaces with defects, and the ability of the Y and Ti films to mitigate irradiation-assisted oxidation. The aforementioned experimental work will be closely coupled with multi-scale molecular dynamics (MD) modeling to understand the reactions at the surface, the transport of oxidant through the thin film, and the stabilities of the deposited thin films under radiation and oxidation. Simulations of materials property changes under conditions of radiation and oxidation require multiple size domains and a different simulation scheme for each of these domains. This will be achieved by coupling the FPMD and coarse-grained kinetic Monte Carlo (KMC). This will enable the comparison of the results of each simulation approach with the experimental results.

Sridharan, Kumar; Zhang, Jinsuo

2014-01-09T23:59:59.000Z

204

Method for preparing high cure temperature rare earth iron compound magnetic material  

DOE Patents [OSTI]

Insertion of light elements such as H,C, or N in the R.sub.2 Fe.sub.17 (R=rare earth metal) series has been found to modify the magnetic properties of these compounds, which thus become prospective candidates for high performance permanent magnets. The most spectacular changes are increases of the Curie temperature, T.sub.c, of the magnetization, M.sub.s, and of coercivity, H.sub.c, upon interstitial insertion. A preliminary product having a component R--Fe--C,N phase is produced by a chemical route. Rare earth metal and iron amides are synthesized followed by pyrolysis and sintering in an inert or reduced atmosphere, as a result of which, the R--Fe--C,N phases are formed. Fabrication of sintered rare earth iron nitride and carbonitride bulk magnet is impossible via conventional process due to the limitation of nitridation method.

Huang, Yuhong (West Hills, CA); Wei, Qiang (West Hills, CA); Zheng, Haixing (Oak Park, CA)

2002-01-01T23:59:59.000Z

205

E-Print Network 3.0 - advanced magnetic materials Sample Search...  

Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

B. ParkerJ. Cozzolino S. Peggs... W. Louie E. WillenJ. Muratore 12;Construction and Test of the Magnetic Mirror Model of the HTS RIA Source: Gupta, Ramesh - Superconducting...

206

External proton beam analysis of plasma facing materials for magnetic confinement fusion applications  

E-Print Network [OSTI]

A 1.7MV tandem accelerator was reconstructed and refurbished for this thesis and for surface science applications at the Cambridge laboratory for accelerator study of surfaces (CLASS). At CLASS, an external proton beam ...

Barnard, Harold Salvadore

2009-01-01T23:59:59.000Z

207

Methods and materials for nanocrystalline surface coatings and attachment of peptide amphiphile nanofibers thereon  

DOE Patents [OSTI]

Biocompatible composites comprising peptide amphiphiles and surface modified substrates and related methods for attachment thereon.

Stupp, Samuel I. (Chicago, IL); Spoerke, Erik D. (Albuquerque, NM); Anthony, Shawn G. (New Stanton, PA); Niece; Krista L. (Evanston, IL)

2008-06-24T23:59:59.000Z

208

Development of accelerator based spatially resolved ion beam analysis techniques for the study of plasma materials interactions in magnetic fusion devices  

E-Print Network [OSTI]

Plasma-material interactions (PMI) in magnetic fusion devices pose significant scientific and engineering challenges for the development of steady-state fusion power reactors. Understanding PMI is crucial for the develpment ...

Barnard, Harold Salvadore

2014-01-01T23:59:59.000Z

209

Temperature and magnetic field dependent optical spectral weight in the cation-deficient colossal-magnetoresistance material La0.936Mn0.982O3  

E-Print Network [OSTI]

with the general arguments, a broad peak has been observed in 1 various Mn-based CMR materials by several groupsTemperature and magnetic field dependent optical spectral weight in the cation-deficient colossal on single-crystal samples as a function of temperature and at zero and 0.5 T magnetic fields

Homes, Christopher C.

210

Interplay of superconductivity, magnetism, and density waves in rare-earth tritellurides and iron-based superconducting materials  

E-Print Network [OSTI]

3. Magnetism in Metals . . . . . . . . . . . . . . . . .IV Superconductivity and Magnetism in Iron-PnictideIII Superconductivity, Magnetism and Charge-Density Waves in

Zocco, Diego Andrés

2011-01-01T23:59:59.000Z

211

Surface-Gasification Materials Program. Semiannual progress report for the period ending March 31, 1983  

SciTech Connect (OSTI)

Contents of this semiannual report include the following: introduction; (1) plant materials surveillance tests (Illinois Institute of Technology); (2) slagging gasifier refractories - appliction/evaluation (Argonne National Laboratory); (3) protective clothing and claddings - application/evaluation (ANL); (4) ceramic application technology - brittle material design (LANL); (5) advanced pressure vessel materials technology (ORNL); (6) electroslag component casting (ORNL); (7) cost reduction of the electroslag casting manufacturing process (CMU); (8) materials review and component failure analysis in support of coal gasification processes and plants (ANL); (9) process plant materials review, evaluation, and support (ORNL).

Bradley, R.A. (comp.)

1983-05-01T23:59:59.000Z

212

Surfaces  

E-Print Network [OSTI]

Surfaces is a collection of four individual essays which focus on the characteristics and tactile qualities of surfaces within a variety of perceived landscapes. Each essay concentrates on a unique surface theme and purpose; ...

DeMaio, Ernest Vincent, 1964-

1989-01-01T23:59:59.000Z

213

Surface reconstruction and chemical evolution of stoichiometric layered cathode materials for lithium-ion batteries  

E-Print Network [OSTI]

Layered Oxides for Lithium Batteries. Nano Lett. 13, 3857–O 2 Cathode Material in Lithium Ion Batteries. Adv. Energydecomposition in lithium ion batteries: first-principles

Lin, Feng

2014-01-01T23:59:59.000Z

214

Investigation of IAQ-Relevant Surface Chemistry and Emissions on HVAC Filter Materials  

SciTech Connect (OSTI)

Chemical reactions involving ozone of outdoor origin and indoor materials are known to be significant sources of formaldehyde and other irritant gas-phase oxidation products in the indoor environment. HVAC filters are exposed to particularly high ozone concentrations--close to outdoor levels. In this study, we investigated chemical processes taking place on the surface of filters that included fiberglass, polyester, cotton/polyester blend and synthetic (e.g., polyolefin) filter media. Ozone reactions were studied on unused filter media, and on filters that were deployed for 3 months in two different locations: at the Lawrence Berkeley National Laboratory and at the Port of Oakland. Specimens from each filter were exposed to ozone under controlled conditions in a laboratory flow tube at a constant flow of dry or humidified air (50percent relative humidity). Ozone was generated with a UV source upstream of the flow tube, and monitored using a photometric detector. Ozone breakthrough curves were recorded for each sample exposed to ~;;150 ppbv O3 for periods of ~;;1000 min, from which we estimated their uptake rate. Most experiments were performed at 1.3 L/min (corresponding to a face velocity of 0.013 m/s), except for a few tests performed at a higher airflow rate, to obtain a face velocity of 0.093 m/s, slightly closer to HVAC operation conditions. Formaldehyde and acetaldehyde, two oxidation byproducts, were collected downstream of the filter and quantified. Emissions of these volatile aldehydes were consistently higher under humidified air than under dry conditions, at which levels were near the limit of detection. Our results confirm that there are significant reactions of ozone as air containing ozone flows through HVAC filters, particularly when the filters are loaded with particles and the air is humidified. The amount of ozone reacted was not clearly related to the types of filter media, e.g., fiberglass versus synthetic. Specific fiberglass filters that were coated with an impaction oil showed significantly higher formaldehyde emissions than most other samples. Those emissions were magnified in the presence of particles (i.e., in used filters), and were observed even in the absence of ozone, which suggests that hydrolysis of filter binder or tackifier additives may be the reason for those high emissions. Mass balance calculations indicate that the emission rates of formaldehyde and acetaldehyde from the filters are generally not large enough to substantially increase indoor formaldehyde or acetaldehyde concentrations.

Destaillats, Hugo; Fisk, William J.

2010-02-01T23:59:59.000Z

215

Incorporation of 4d and 5d Transition Metal Cyanometallates into Magnetic Clusters and Materials.  

E-Print Network [OSTI]

AND PENTADECANUCLEAR CLUSTERS BASED ON MV(CN)8 (M = Mo, W) AND NiII .............. 35 Introduction .................................................................................... 35 Experimental Section... scheme of Prussian Blue analogs, M' = V,Cr, Fe, Co, M = V, Cr, Mn, Fe, Ni , L = labile ligand or solvent molecule. 6 cancel, and the remaining unpaired spins align with the field as a ferromagnet does (Scheme 2a). Although these magnetic...

Hilfiger, Matthew Gary

2011-08-08T23:59:59.000Z

216

Superconductivity on the surface of topological insulators and in two-dimensional noncentrosymmetric materials  

E-Print Network [OSTI]

Superconductivity on the surface of topological insulators and in two, as it pertains to the surface of a three-dimensional time-reversal symmetric topological band insulator. We also TRS topological band insulator.7­9 In a recent work, Hor et al.10 have reported the observation

217

Performance of a copper-lithium alloy as an impurity control system surface material for a fusion reactor  

SciTech Connect (OSTI)

A copper-lithium alloy was evaluated as a surface material for the impurity control system of the INTOR reactor. Both the medium edge temperature limiter regime and the low edge temperature divertor regime were examined. The analysis used TRIM code data to predict sputtering coefficients for copper-lithium with a 1.5 monolayer coverage of lithium. The REDEP code was used to evaluate the erosion performance for INTOR. Other properties such as fabrication and thermal performance were also briefly assessed. It was found, from the standpoint of erosion, that copper-lithium is a very good candidate material for the medium edge temperature regime, and also works well in the low edge temperature regime. For the medium edge temperature regime, the use of copper-lithium results in an almost negligible erosion rate over the entire limiter surface.

Brooks, J.N.; Krauss, A.R.; Mattas, R.F.; DeWald, A.B.

1984-10-01T23:59:59.000Z

218

Materials  

Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE:1 First Use of Energy for All Purposes (Fuel and Nonfuel),Feet) Year Jan Feb Mar Apr May JunDatastreamsmmcrcalgovInstrumentsrucLas Conchas recovery challenge fund LasDubey selectedContract Research Material

219

Quasi-continuum photoluminescence: Unusual broad spectral and temporal characteristics found in defective surfaces of silica and other materials  

SciTech Connect (OSTI)

We previously reported a novel photoluminescence (PL) with a distribution of fast decay times in fused silica surface flaws that is correlated with damage propensity by high fluence lasers. The source of the PL was not attributable to any known silica point defect. Due to its broad spectral and temporal features, we here give this PL the name quasi-continuum PL (QC-PL) and describe the features of QC-PL in more detail. The primary features of QC-PL include broad excitation and emission spectra, a broad distribution of PL lifetimes from 20 ps to 5?ns, continuous shifts in PL lifetime distributions with respect to emission wavelength, and a propensity to photo-bleach and photo-brighten. We found similar PL characteristics in surface flaws of other optical materials, including CaF{sub 2}, DKDP, and quartz. Based on the commonality of the features in different optical materials and the proximity of QC-PL to surfaces, we suggest that these properties arise from interactions associated with high densities of defects, rather than a distribution over a large number of types of defects and is likely found in a wide variety of structures from nano-scale composites to bulk structures as well as in both broad and narrow band materials from dielectrics to semiconductors.

Laurence, Ted A., E-mail: laurence2@llnl.gov; Bude, Jeff D.; Shen, Nan; Steele, William A.; Ly, Sonny [Physical and Life Sciences and National Ignition Facility, Lawrence Livermore National Laboratory, 7000 East Avenue, Livermore, California 94550 (United States)

2014-02-28T23:59:59.000Z

220

Atomistic Simulations of Bonding, Thermodynamics, and Surface Passivation in Nanoscale Solid Propellant Materials  

E-Print Network [OSTI]

, such as mercury fulminate, lead azide, lead styphnate or tetrazine. Initiation can also occur by hot spots in the material, which are produced by adiabatic compression of small air pockets. Once initiated, explosive reactions are driven by large free energy...

Williams, Kristen

2012-10-19T23:59:59.000Z

Note: This page contains sample records for the topic "magnetism materials surface" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


221

Nanostructured multifunctional materials for control of light transport and surface wettability  

E-Print Network [OSTI]

Biological surfaces have evolved to optimize their structures and physical and chemical properties at the micro/nanoscale for adaptation to different environments, exhibiting a wide variety of beneficial functions, ranging ...

Choi, Hyungryul

2014-01-01T23:59:59.000Z

222

Scrub-resistance Characteristics of Kitchen and Bathroom Wall-surfacing Materials.  

E-Print Network [OSTI]

-resistance characteristics discussed. an abrasive cleanser. Loss of gloss continued bv: A statistical analysis was made to evaluate the at a much slower rate as the scrubbing progressed, gloss differences which resulted from 30-minute Ceramic tile, porcelain...-on-stee: ceramic tile and stainless steel showed the leas' change in gloss, following 30 minutes of scrubbing These materials showed significantly less changs than the other materials subjected to the same scrubbing operations. Plastic tiles, flexible rubber...

Hobgood, Price; Kunze, O. R.; Stewart, B. R.

1960-01-01T23:59:59.000Z

223

Method of bonding functional surface materials to substrates and applications in microtechnology and antifouling  

DOE Patents [OSTI]

A simple and effective method to bond a thin coating of poly(N-isopropylacylamide) (NIPAAm) on a glass surface by UV photopolymerization, and the use of such a coated surface in nano and micro technology applications. A silane coupling agent with a dithiocarbamate group is provided as a photosensitizer, preferably, (N,N'-diethylamine)dithiocarbamoylpropyl-(trimethoxy)silane (DATMS). The thiocarbamate group of the sensitizer is then bonded to the glass surface by coupling the silane agent with the hydroxyl groups on the glass surface. The modified surface is then exposed to a solution of NIPAAm and a crosslinking agent which may be any organic molecule having an acrylamide group and at least two double bonds in its structure, such as N,N'-methylenebisacrylamide, and a polar solvent which may be any polar liquid which will dissolve the monomer and the crosslinking agent such as acetone, water, ethanol, or combinations thereof. By exposing the glass surface to a UV light, free radicals are generated in the thiocarbamate group which then bonds to the crosslinking agent and the NIPAAm. Upon bonding, the crosslinking agent and the NIPAAm polymerize to form a thin coating of PNIPAAm bonded to the glass. Depending upon the particular configuration of the glass, the properties of the PNIPAAm allow applications in micro and nano technology.

Feng, Xiangdong (West Richland, WA); Liu, Jun (West Richland, WA); Liang, Liang (Richland, WA)

1999-01-01T23:59:59.000Z

224

Method of bonding functional surface materials to substrates and applications in microtechnology and anti-fouling  

DOE Patents [OSTI]

A simple and effective method to bond a thin coating of poly(N-isopropylacylamide) (NIPAAm) on a glass surface by UV photopolymerization, and the use of such a coated surface in nano and micro technology applications. A silane coupling agent with a dithiocarbamate group is provided as a photosensitizer preferably, (N,N'-diethylamine) dithiocarbamoylpropyl-(trimethoxy) silane (DATMS). The thiocarbamate group of the sensitizer is then bonded to the glass surface by coupling the silane agent with the hydroxyl groups on the glass surface. The modified surface is then exposed to a solution of NIPAAm and a crosslinking agent which may be any organic molecule having an acrylamide group and at least two double bonds in its structure, such as N, N'-methylenebisacrylamide, and a polar solvent which may be any polar liquid which will dissolve the monomer and the crosslinking agent such as acetone, water, ethanol, or combinations thereof. By exposing the glass surface to a UV light, free radicals are generated in the thiocarbamate group which then bonds to the crosslinking agent and the NIPAAm. Upon bonding, the crosslinking agent and the NIPAAm polymerize to form a thin coating of PNIPAAm bonded to the glass. Depending upon the particular configuration of the glass, the properties of the PNIPAAm allow applications in micro and nano technology.

Feng, Xiangdong (West Richland, WA); Liu, Jun (West Richland, WA); Liang, Liang (Richland, WA)

2001-01-01T23:59:59.000Z

225

Rare-Earth-Free Nanostructure Magnets: Rare-Earth-Free Permanent Magnets for Electric Vehicle Motors and Wind Turbine Generators: Hexagonal Symmetry Based Materials Systems Mn-Bi and M-type Hexaferrite  

SciTech Connect (OSTI)

REACT Project: The University of Alabama is developing new iron- and manganese-based composite materials for use in the electric motors of EVs and renewable power generators that will demonstrate magnetic properties superior to today’s best rare-earth-based magnets. Rare earths are difficult and expensive to refine. EVs and renewable power generators typically use rare earths to make their electric motors smaller and more powerful. The University of Alabama has the potential to improve upon the performance of current state-of-the-art rare-earth-based magnets using low-cost and more abundant materials such as manganese and iron. The ultimate goal of this project is to demonstrate improved performance in a full-size prototype magnet at reduced cost.

None

2012-01-01T23:59:59.000Z

226

The application of iodine and magnetic susceptibility surface geochemical surveys in the Lodgepole Play, Eastern Williston Basin, North Dakota  

SciTech Connect (OSTI)

The use of surface geochemistry as a first pass exploration tool is becoming more prevalent in petroleum exploration. This is especially true due to the high cost of 2-D and 3-D surveys in defining small targets such as the Waulsortian mounds of the Lodgepole Formation. Surface geochemical surveys are very effective in pinpointing specific target areas for seismic surveying and thus reducing costs. Presented are examples of surface geochemical surveys utilizing magnetic susceptibility and iodine methods in delineating reservoirs in the Lodgepole, Mission Canyon and Red River formations. The types of surveys presented vary from reconnaissance to detail and examples of how to define a grid will be discussed. Surface geochemical surveys can be very effective when the areal extent of the target(s) and the purpose of the survey are clearly defined prior to implementation. By determining which areas have microseepage and which areas do not, surface geochemistry can be a very effective tool in focusing exploration efforts and maximizing exploration dollars.

Tedesco, S.A. [Atoka Geochemical Services Corp., Englewood, CO (United States)

1996-06-01T23:59:59.000Z

227

Method of making active magnetic refrigerant, colossal magnetostriction and giant magnetoresistive materials based on Gd-Si-Ge alloys  

DOE Patents [OSTI]

Method of making an active magnetic refrigerant represented by Gd.sub.5 (Si.sub.x Ge.sub.1-x).sub.4 alloy for 0.ltoreq.x.ltoreq.1.0 comprising placing amounts of the commercially pure Gd, Si, and Ge charge components in a crucible, heating the charge contents under subambient pressure to a melting temperature of the alloy for a time sufficient to homogenize the alloy and oxidize carbon with oxygen present in the Gd charge component to reduce carbon, rapidly solidifying the alloy in the crucible, and heat treating the solidified alloy at a temperature below the melting temperature for a time effective to homogenize a microstructure of the solidified material, and then cooling sufficiently fast to prevent the eutectoid decomposition and improve magnetocaloric and/or the magnetostrictive and/or the magnetoresistive properties thereof.

Gschneidner, Jr., Karl A. (Ames, IA); Pecharsky, Alexandra O. (Ames, IA); Pecharsky, Vitalij K. (Ames, IA)

2003-07-08T23:59:59.000Z

228

The Role of Material Porosity on Ozone Uptake for Metakaolin-Concrete Surfaces  

E-Print Network [OSTI]

to a diminished environmental impact, clay may cause increased removal of ozone, an important indoor pollutant velocity, Heterogeneous Chemistry, Construction Materials 1 Introduction Metakaolin-cement systems hold ozone uptake. Cement is an essential component in the building industry used in formulating concrete

Siegel, Jeffrey

229

Oxidation of carbon fiber surfaces for use as reinforcement in high-temperature cementitious material systems  

DOE Patents [OSTI]

The interfacial bond characteristics between carbon fiber and a cement matrix, in high temperature fiber-reinforced cementitious composite systems, can be improved by the oxidative treatment of the fiber surfaces. Compositions and the process for producing the compositions are disclosed. 2 figs.

Sugama, Toshifumi.

1990-05-22T23:59:59.000Z

230

Oxidation of carbon fiber surfaces for use as reinforcement in high-temperature cementitious material systems  

DOE Patents [OSTI]

The interfacial bond characteristics between carbon fiber and a cement matrix, in high temperature fiber-reinforced cementitious composite systems, can be improved by the oxidative treatment of the fiber surfaces. Compositions and the process for producing the compositions are disclosed.

Sugama, Toshifumi (Mastic Beach, NY)

1990-01-01T23:59:59.000Z

231

LANL Virtual Center for Chemical Hydrogen Storage: Chemical Hydrogen Storage Using Ultra-high Surface Area Main Group Materials  

SciTech Connect (OSTI)

The focus of the project was to design and synthesize light element compounds and nanomaterials that will reversibly store molecular hydrogen for hydrogen storage materials. The primary targets investigated during the last year were amine and hydrogen terminated silicon (Si) nanoparticles, Si alloyed with lighter elements (carbon (C) and boron (B)) and boron nanoparticles. The large surface area of nanoparticles should facilitate a favorable weight to volume ratio, while the low molecular weight elements such as B, nitrogen (N), and Si exist in a variety of inexpensive and readily available precursors. Furthermore, small NPs of Si are nontoxic and non-corrosive. Insights gained from these studies will be applied toward the design and synthesis of hydrogen storage materials that meet the DOE 2010 hydrogen storage targets: cost, hydrogen capacity and reversibility. Two primary routes were explored for the production of nanoparticles smaller than 10 nm in diameter. The first was the reduction of the elemental halides to achieve nanomaterials with chloride surface termination that could subsequently be replaced with amine or hydrogen. The second was the reaction of alkali metal Si or Si alloys with ammonium halides to produce hydrogen capped nanomaterials. These materials were characterized via X-ray powder diffraction, TEM, FTIR, TG/DSC, and NMR spectroscopy.

Susan M. Kauzlarich; Phillip P. Power; Doinita Neiner; Alex Pickering; Eric Rivard; Bobby Ellis, T. M.; Atkins, A. Merrill; R. Wolf; Julia Wang

2010-09-05T23:59:59.000Z

232

Predicted giant magnetic moment on non-{n0m} surfaces of d-wave superconductors  

E-Print Network [OSTI]

in the [1 (1) over bar 0] direction. Observing these predictions in high-T(c) superconductors can provide a strong confirmation of the d-wave scenario for such materials. [S0163-1829(99)50942-9]....

Hu, Chia-Ren; Yan, XZ.

1999-01-01T23:59:59.000Z

233

Temporal measurements of surfactant squeeze-out from a surface using magnetically levitated liquid bridges  

E-Print Network [OSTI]

A cylindrical liquid bridge, laden with surfactant and constrained at the two ends by circular rods area Langmuir trough with a plate that monitors the surface tension [6]. This techni- que is useful

Taylor, Philip L.

234

Real time monitoring of superparamagnetic nanoparticle self-assembly on surfaces of magnetic recording media  

SciTech Connect (OSTI)

Nanoparticle self-assembly dynamics are monitored in real-time by detecting optical diffraction from an all-nanoparticle grating as it self-assembles on a grating pattern recorded on a magnetic medium. The diffraction efficiency strongly depends on concentration, pH, and colloidal stability of nanoparticle suspensions, demonstrating the nanoparticle self-assembly process is highly tunable. This metrology could provide an alternative for detecting nanoparticle properties such as colloidal stability.

Ye, L.; Pearson, T.; Crawford, T. M., E-mail: crawftm@mailbox.sc.edu [Department of Physics and Astronomy, University of South Carolina, 712 Main Street, Columbia, South Carolina 29208 (United States); Qi, B.; Cordeau, Y.; Mefford, O. T. [Department of Materials Science and Engineering, Clemson University, 161 Sirrine Hall, Clemson, South Carolina 29634 (United States); Center for Optical Materials Science and Engineering Technologies (COMSET), 91 Technology Dr., Anderson, South Carolina 29625 (United States)

2014-05-07T23:59:59.000Z

235

Synthesis of Novel Polypeptide-Silica Hybrid Materials through Surface-Initiated N-carboxyanhydride Polymerization  

E-Print Network [OSTI]

synthesis routes derived from sol-gel chemistry .......................... 4 1.3 Polymerization behavior of aqueous silica ............................................................ 11 1.4 Simulated structures from various growth models... are still used; however, the use of sol-gel chemistry for silica matrix construction permits the greatest degree of design flexibility and variety of materials that can be synthesized. Common synthesis techniques derived from sol-gel chemistry have been...

Lunn, Jonathan D.

2011-08-08T23:59:59.000Z

236

Emissivity of Candidate Materials for VHTR Applicationbs: Role of Oxidation and Surface Modification Treatments  

SciTech Connect (OSTI)

The Generation IV (GEN IV) Nuclear Energy Systems Initiative was instituted by the Department of Energy (DOE) with the goal of researching and developing technologies and materials necessary for various types of future reactors. These GEN IV reactors will employ advanced fuel cycles, passive safety systems, and other innovative systems, leading to significant differences between these future reactors and current water-cooled reactors. The leading candidate for the Next Generation Nuclear Plant (NGNP) to be built at Idaho National Lab (INL) in the United States is the Very High Temperature Reactor (VHTR). Due to the high operating temperatures of the VHTR, the Reactor Pressure Vessel (RPV) will partially rely on heat transfer by radiation for cooling. Heat expulsion by radiation will become all the more important during high temperature excursions during off-normal accident scenarios. Radiant power is dictated by emissivity, a material property. The NGNP Materials Research and Development Program Plan [1] has identified emissivity and the effects of high temperature oxide formation on emissivity as an area of research towards the development of the VHTR.

Sridharan, Kumar; Allen, Todd; Anderson, Mark; Cao, Guoping; Kulcinski, Gerald

2011-07-25T23:59:59.000Z

237

Final Report Theoretical Studies of Surface Reactions on Metals and Electronic Materials  

SciTech Connect (OSTI)

This proposal describes the proposed renewal of a theoretical research program on the structure and reactivity of molecules adsorbed on transition metal surfaces. A new direction of the work extends investigations to interfaces between solid surfaces, adsorbates and aqueous solutions and includes fundamental work on photoinduced electron transport into chemisorbed species and into solution. The goal is to discover practical ways to reduce water to hydrogen and oxygen using radiation comparable to that available in the solar spectrum. The work relates to two broad subject areas: photocatalytic processes and production of hydrogen from water. The objective is to obtain high quality solutions of the electronic structure of adsorbate-metal-surface-solution systems so as to allow activation barriers to be calculated and reaction mechanisms to be determined. An ab initio embedding formalism provides a route to the required accuracy. New theoretical methods developed during the previous grant period will be implemented in order to solve the large systems involved in this work. Included is the formulation of a correlation operator that is used to treat localized electron distributions such as ionic or regionally localized distributions. The correlation operator which is expressed as a two-particle projector is used in conjunction with configuration interaction.

Jerry L. Whitten

2012-04-23T23:59:59.000Z

238

Shear-horizontal surface acoustic wave phononic device with high density filling material for ultra-low power sensing applications  

SciTech Connect (OSTI)

Finite element simulations of a phononic shear-horizontal surface acoustic wave (SAW) sensor based on ST 90°-X Quartz reveal a dramatic reduction in power consumption. The phononic sensor is realized by artificially structuring the delay path to form an acoustic meta-material comprised of a periodic microcavity array incorporating high-density materials such as tantalum or tungsten. Constructive interference of the scattered and secondary reflected waves at every microcavity interface leads to acoustic energy confinement in the high-density regions translating into reduced power loss. Tantalum filled cavities show the best performance while tungsten inclusions create a phononic bandgap. Based on our simulation results, SAW devices with tantalum filled microcavities were fabricated and shown to significantly decrease insertion loss. Our findings offer encouraging prospects for designing low power, highly sensitive portable biosensors.

Richardson, M.; Bhethanabotla, V. R., E-mail: bhethana@usf.edu [Department of Chemical and Biomedical Engineering, University of South Florida, Tampa, Florida 33620 (United States); Sankaranarayanan, S. K. R. S. [Center for Nanoscale Materials, Argonne National Laboratory, Argonne, Illinois 60439 (United States)

2014-06-23T23:59:59.000Z

239

Establishing material properties for thin asphalt concrete surfaces on granular bases  

E-Print Network [OSTI]

cross-section of a Goodyear Hi -Miler 10. 00-20 14-ply bias truck tire carcass was obtained; the input data for the Tielking tire model was developed by measuring cord locations, angles, and plies on a section of the tire; and the tire pressure.... Since little work in the past has been done in the area of thin asphalt concrete surface analysis, re-evaluation of several assumptions concerning the tire load were necessary. The truck tire pressures on Texas highways have dramatically increased...

Rosson, Barry Thomas

1985-01-01T23:59:59.000Z

240

National High Magnetic Field Laboratory  

Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

ANNUAL REPORT RESEARCH HIGHLIGHTS: CONDENSED MATTER SCIENCE Technique development, graphene, magnetism & magnetic materials, topological insulators, quantum fl uids & solids,...

Note: This page contains sample records for the topic "magnetism materials surface" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


241

Energy Saving Melting and Revert Reduction Technology (Energy-SMARRT): Surface/Near Surface Indication - Characterization of Surface Anomalies from Magnetic Particle and Liquid Penetrant Indications  

SciTech Connect (OSTI)

The systematic study and characterization of surface indications has never been conducted. Producers and users of castings do not have any data on which they can reliably communicate the nature of these indications or their effect on the performance of parts. Clearly, the ultimate intent of any work in this area is to eliminate indications that do in fact degrade properties. However, it may be impractical physically and/or financially to eliminate all surface imperfections. This project focused on the ones that actually degrade properties. The initial work was to identify those that degrade properties. Accurate numerical simulations of casting service performance allow designers to use the geometric flexibility of castings and the superior properties of steel to produce lighter weight and more energy efficient components for transportation systems (cars and trucks), construction, and mining. Accurate simulations increase the net melting energy efficiency by improving casting yield and reducing rework and scrap. Conservatively assuming a 10% improvement in yield, approximately 1.33 x 1012 BTU/year can be saved with this technology. In addition, CO2 emissions will be reduced by approximately 117,050 tons per year.

Griffin, John [university of Alabama - Birmingham] [university of Alabama - Birmingham

2014-02-20T23:59:59.000Z

242

Investigations of the electronic and magnetic structures of Co{sub 2}YGa (Y=Cr, Mn) Heusler alloys and their (100) surfaces  

SciTech Connect (OSTI)

Density functional theory calculations are performed to investigate the structural, electronic, and magnetic properties of bulk structures of Co{sub 2}YGa (Y?=?Cr, Mn) Heusler alloys and the surfaces along the (100) orientation. The bulk structures of both alloys show a ferromagnetic behavior with total magnetic moments of 3.03?{sub B} and 4.09?{sub B} and high spin polarizations of 99% and 67% for Co{sub 2}CrGa and Co{sub 2}MnGa, respectively. The surfaces are found to exhibit corrugations due to different relaxations of the surface atoms. For the case of Co{sub 2}CrGa, two surfaces preserve the half metallicity, namely those with Cr-Ga and Ga– terminations with high spin polarizations above 90%, whereas it dropped to about 50% for the other surfaces. However, the spin polarizations of Co-Co and Mn-Ga terminated surfaces remain close to that of bulk Co{sub 2}MnGa alloy, whereas it is suppressed down to 17% for Co– termination. The highest local magnetic moments are found to be 3.26??{sub B} and 4.11??{sub B} for Cr and Mn surface atoms in Cr-Ga and Mn– terminated surfaces, respectively.

Hamad, Bothina, E-mail: b.hamad@ju.edu.jo [Physics Department, The University of Jordan, Amman-11942 (Jordan)

2014-03-21T23:59:59.000Z

243

Estimation of Hourly Solar Loads on the Surfaces of Moving Refrigerated Tractor Trailers Outfitted with Phase Change Materials (PCMs) for Several Routes across the Continental U.S.  

E-Print Network [OSTI]

The primary objective of this thesis was to calculate solar loads, wind chill temperatures on the surfaces of moving refrigerated tractor trailers outfitted with phase change materials (PCMs) for several routes across the Continental United States...

Varadarajan, Krupasagar

2011-08-31T23:59:59.000Z

244

Equipotential Surfaces of a Plasma MOving in a Toroidal Octupole Magnetic Pield  

E-Print Network [OSTI]

. Atomic Energy Commission #12;COO-1233-32 Equipotential Surfaces of a Plasma Moving in a Toroidal Octupo1e. Soc. II, 11, 452 (1966) * Work Supported by the ".. S. Atomic Energy Commission : . #12;2 INTRODUCTION. Potentials were measured with electrostatic probes located at various ports around the machine The probes

Sprott, Julien Clinton

245

Heavy ion Rutherford Backscattering Spectrometry (HIRBS) for the near surface characterization of electronic materials  

SciTech Connect (OSTI)

The use of heavy ion projectiles for Rutherford Backscattering Spectrometry (RBS) provides several potential advantages over conventional RBS with /sup 4/He beams. Among these advantages are the improved mass resolution for heavy elements (>50 amu) and the increased accessible depth of analysis. A series of experiments using 20-MeV /sup 16/O beam backscattered from a variety of targets was performed in order to examine the potential advantages of heavy ion RBS in the near-surface characterization of semiconductors with masses >50 amu. Important questions such as mass resolution, depth resolution, isotopic effects, absolute sensitivity and minimum detectable limit of impurities were investigated. Ion implantations and multiple layered structures on GaAs substrates as well as metal germanide systems were studied. The development of the method in conjunction with the channeling technique is also discussed.

Yu, K.M.

1984-12-01T23:59:59.000Z

246

GUIDANCE FOR THE PROPER CHARACTERIZATION AND CLASSIFICATION OF LOW SPECIFIC ACTIVITY MATERIALS AND SURFACE CONTAMINATED OBJECTS FOR DISPOSAL  

SciTech Connect (OSTI)

Regulatory concerns over the proper characterization of certain waste streams led CH2M HILL Plateau Remediation Company (CHPRC) to develop written guidance for personnel involved in Decontamination & Decommissioning (D&D) activities, facility management and Waste Management Representatives (WMRs) involved in the designation of wastes for disposal on and off the Hanford Site. It is essential that these waste streams regularly encountered in D&D operations are properly designated, characterized and classified prior to shipment to a Treatment, Storage or Disposal Facility (TSDF). Shipments of waste determined by the classification process as Low Specific Activity (LSA) or Surface Contaminated Objects (SCO) must also be compliant with all applicable U.S. Department of Transportation (DOE) regulations as well as Department of Energy (DOE) orders. The compliant shipment of these waste commodities is critical to the Hanford Central Plateau cleanup mission. Due to previous problems and concerns from DOE assessments, CHPRC internal critiques as well as DOT, a management decision was made to develop written guidance and procedures to assist CHPRC shippers and facility personnel in the proper classification of D&D waste materials as either LSA or SCO. The guidance provides a uniform methodology for the collection and documentation required to effectively characterize, classify and identify candidate materials for shipping operations. A primary focus is to ensure that waste materials generated from D&D and facility operations are compliant with the DOT regulations when packaged for shipment. At times this can be difficult as the current DOT regulations relative to the shipment of LSA and SCO materials are often not clear to waste generators. Guidance is often sought from NUREG 1608/RAMREG-003 [3]: a guidance document that was jointly developed by the DOT and the Nuclear Regulatory Commission (NRC) and published in 1998. However, NUREG 1608 [3] is now thirteen years old and requires updating to comply with the newer DOT regulations. Similar challenges present themselves throughout the nuclear industry in both commercial and government operations and therefore, this is not only a Hanford Site problem. Shipping radioactive wastes as either LSA or SCO rather than repacking it is significantly cheaper than other DOT radioactive materials shipping classifications particularly when the cost of packages is included. Additionally, the need to 'repackage' materials for transport can often increase worker exposure, necessitated by 'repackaging' waste materials into DOT 7 A Type A containers.

PORTSMOUTH JH; BLACKFORD LT

2012-02-13T23:59:59.000Z

247

Review of the margins for ASME code fatigue design curve - effects of surface roughness and material variability.  

SciTech Connect (OSTI)

The ASME Boiler and Pressure Vessel Code provides rules for the construction of nuclear power plant components. The Code specifies fatigue design curves for structural materials. However, the effects of light water reactor (LWR) coolant environments are not explicitly addressed by the Code design curves. Existing fatigue strain-vs.-life ({var_epsilon}-N) data illustrate potentially significant effects of LWR coolant environments on the fatigue resistance of pressure vessel and piping steels. This report provides an overview of the existing fatigue {var_epsilon}-N data for carbon and low-alloy steels and wrought and cast austenitic SSs to define the effects of key material, loading, and environmental parameters on the fatigue lives of the steels. Experimental data are presented on the effects of surface roughness on the fatigue life of these steels in air and LWR environments. Statistical models are presented for estimating the fatigue {var_epsilon}-N curves as a function of the material, loading, and environmental parameters. Two methods for incorporating environmental effects into the ASME Code fatigue evaluations are discussed. Data available in the literature have been reviewed to evaluate the conservatism in the existing ASME Code fatigue evaluations. A critical review of the margins for ASME Code fatigue design curves is presented.

Chopra, O. K.; Shack, W. J.; Energy Technology

2003-10-03T23:59:59.000Z

248

Surface Anchoring of Nematic Phase on Carbon Nanotubes: Nanostructure of Ultra-High Temperature Materials  

SciTech Connect (OSTI)

Nuclear energy is a dependable and economical source of electricity. Because fuel supply sources are available domestically, nuclear energy can be a strong domestic industry that can reduce dependence on foreign energy sources. Commercial nuclear power plants have extensive security measures to protect the facility from intruders [1]. However, additional research efforts are needed to increase the inherent process safety of nuclear energy plants to protect the public in the event of a reactor malfunction. The next generation nuclear plant (NGNP) is envisioned to utilize a very high temperature reactor (VHTR) design with an operating temperature of 650-1000�°C [2]. One of the most important safety design requirements for this reactor is that it must be inherently safe, i.e., the reactor must shut down safely in the event that the coolant flow is interrupted [2]. This next-generation Gen IV reactor must operate in an inherently safe mode where the off-normal temperatures may reach 1500�°C due to coolant-flow interruption. Metallic alloys used currently in reactor internals will melt at such temperatures. Structural materials that will not melt at such ultra-high temperatures are carbon/graphtic fibers and carbon-matrix composites. Graphite does not have a measurable melting point; it is known to sublime starting about 3300�°C. However, neutron radiation-damage effects on carbon fibers are poorly understood. Therefore, the goal of this project is to obtain a fundamental understanding of the role of nanotexture on the properties of resulting carbon fibers and their neutron-damage characteristics. Although polygranular graphite has been used in nuclear environment for almost fifty years, it is not suitable for structural applications because it do not possess adequate strength, stiffness, or toughness that is required of structural components such as reaction control-rods, upper plenum shroud, and lower core-support plate [2,3]. For structural purposes, composites consisting of strong carbon fibers embedded in a carbon matrix are needed. Such carbon/carbon (C/C) composites have been used in aerospace industry to produce missile nose cones, space shuttle leading edge, and aircraft brake-pads. However, radiation-tolerance of such materials is not adequately known because only limited radiation studies have been performed on C/C composites, which suggest that pitch-based carbon fibers have better dimensional stability than that of polyacrylonitrile (PAN) based fibers [4]. The thermodynamically-stable state of graphitic crystalline packing of carbon atoms derived from mesophase pitch leads to a greater stability during neutron irradiation [5]. The specific objectives of this project were: (i) to generating novel carbonaceous nanostructures, (ii) measure extent of graphitic crystallinity and the extent of anisotropy, and (iii) collaborate with the Carbon Materials group at Oak Ridge National Lab to have neutron irradiation studies and post-irradiation examinations conducted on the carbon fibers produced in this research project.

Ogale, Amod A

2012-04-27T23:59:59.000Z

249

SURFACE-MODIFIED FERRITIC INTERCONNECT MATERIALS FOR SOLID OXIDE FUEL CELLS  

SciTech Connect (OSTI)

Interconnects are a critical element of an SOFC assembly and although much work has focused on chromium and chromium-iron alloys containing an oxide that is both oxidation resistant and electrically conductive, the thermal instability of typical native metal oxides allow interdiffusion of cations across the interconnect-electrode boundary that ultimately leads to degradation of SOFC performance. Phase I of the SECA Core Technology Program has been a one-year effort to investigate and evaluate the feasibility of: (1) Ion implanting an alumina-scale forming ferritic steel, such as FeCrAlY, to form an interconnect material with low resistance (< 0.1 {Omega}/cm{sup 2}) in oxidizing/reducing environments up to 800 C, and (2) Maintaining the above low resistance metric for an extended time (> 1000 hours at 800 C) in contact with an LSF cathode material. We confirmed, as part of our oxidation kinetics evaluation of FeCrAlY and 430 ferritic steel, the parabolic growth of a mixed chromia/alumina scale on FeCrAlY and a single chromia layer in the case of the 430 stainless steel; the outer contiguous layer of Al{sub 2}O{sub 3}, in the case of FeCrAlY, forming a stable, self-limiting, protective scale with no detectable cation interdiffusion between FeCrAlY and an LSF electrode even after 1000 hours at 800 C in air. To render the alumina scale conductive, we implanted either titanium or niobium ions into FeCrAlY scales to a fixed depth (0.12 {micro}m), varying only the thickness of the oxide. ASR for an un-doped FeCrAlY oxide scale (i.e., alumina) was more than an order of magnitude greater than the 430 control sample whereas, the ASR for the doped FeCrAlY oxide scale sample was comparable to the 430 control sample; hence, the resistance of a doped alumina scale on FeCrAlY was equal to the resistance of a chromia-scale forming alloy, such as 430 (chromia scales of which are typically < 0.1 {Omega}-cm). Along with the ASR measurements, AC impedance measurements were conducted to evaluate conduction mechanisms. From the AC impedance measurements, we observed that the addition of niobium resulted in at least a two order of magnitude reduction in resistance over the un-doped specimen and that the conduction in the doped alumina scale was pure electronic conduction, as opposed to mixed ionic-electronic conduction (dominated by intrinsic (ionic) defects) for the un-doped alumina scales. The DC resistance component was {approx}4 {Omega} although when this value is adjusted to account for the system resistance (i.e., leads, junctions, etc.), the ASR was determined to be < 0.1 {Omega}-cm; even after 1000 hours at 800 C in air. Our results have clearly shown that dopant additions increase the electronic conductivity of alumina forming scale alloys, such as FeCrAlY, transforming from a mixed ionic/electronic conduction mechanism. Just as importantly, the demonstrated stable formation of an alumina scale was shown to be an advantage over conventional pure chromia forming alloys as interconnect materials.

Bruce R. Lanning; James Arps; Ronghua Wei; Goeff Dearnaley

2004-03-15T23:59:59.000Z

250

Simulation of the influence high-frequency (2 MHz) capacitive gas discharge and magnetic field on the plasma sheath near a surface in hypersonic gas flow  

SciTech Connect (OSTI)

The plasma sheath near the surface of a hypersonic aircraft formed under associative ionization behind the shock front shields the transmission and reception of radio signals. Using two-dimensional kinetic particle-in-cell simulations, we consider the change in plasma-sheath parameters near a flat surface in a hypersonic flow under the action of electrical and magnetic fields. The combined action of a high-frequency 2-MHz capacitive discharge, a constant voltage, and a magnetic field on the plasma sheath allows the local electron density to be reduced manyfold.

Schweigert, I. V., E-mail: ischweig@itam.nsc.ru [Russian Academy of Sciences, Khristianovich Institute of Theoretical and Applied Mechanics, Siberian Branch (Russian Federation)

2012-08-15T23:59:59.000Z

251

Journal of Magnetism and MagneticMaterials 148 (1995) 40-41 studies of bct Fe(100)p(1 1)/Pd(100) films  

E-Print Network [OSTI]

transitions in low dimensions, but also from the recent interest in the devel- opment of novel and sophisticated electronic and magnetic devices of dimensions in the nanometer range which re- quires oscillatory ferromagnetic exchange coupling be- tween magnetic layers separated by nonmagnetic spacer layers

Rau, Carl

252

Interplay of superconductivity, magnetism, and density waves in rare-earth tritellurides and iron-based superconducting materials  

E-Print Network [OSTI]

B. Superconductivity . . . . . . . . . . . . . . . . .IV Superconductivity and Magnetism in Iron-PnictideSearch for Pressure Induced Superconductivity in Undoped Ce-

Zocco, Diego Andrés

2011-01-01T23:59:59.000Z

253

Is the friction angle the maximum slope of a free surface of a non cohesive material?  

E-Print Network [OSTI]

Starting from a symmetric triangular pile with a horizontal basis and rotating the basis in the vertical plane, we have determined the evolution of the stress distribution as a function of the basis inclination using Finite Elements method with an elastic-perfectly plastic constitutive model, defined by its friction angle, without cohesion. It is found that when the yield function is the Drucker-Prager one, stress distribution satisfying equilibrium can be found even when one of the free-surface slopes is larger than the friction angle. This means that piles with a slope larger than the friction angle can be (at least) marginally stable and that slope rotation is not always a destabilising perturbation direction. On the contrary, it is found that the slope cannot overpass the friction angle when a Mohr-Coulomb yield function is used. Theoretical explanation of these facts is given which enlightens the role plaid by the intermediate principal stress in both cases of the Mohr-Coulomb criterion and of the Drucker-Prager one. It is then argued that the Mohr-Coulomb criterion assumes a spontaneous symmetry breaking, as soon as the two smallest principal stresses are different ; this is not physical most likely; so this criterion shall be replaced by a Drucker-Prager criterion in the vicinity of the equality, which leads to the previous anomalous behaviour ; so these numerical computations enlighten the avalanche process: they show that no dynamical angle larger than the static one is needed to understand avalanching. It is in agreement with previous experimental results. Furthermore, these results show that the maximum angle of repose can be modified using cyclic rotations; we propose a procedure that allows to achieve a maximum angle of repose to be equal to the friction angle .

A. Modaressi; P. Evesque

2005-07-13T23:59:59.000Z

254

Organic Light-Emitting Diodes (OLEDs) and Optically-Detected Magnetic Resonance (ODMR) studies on organic materials  

SciTech Connect (OSTI)

Organic semiconductors have evolved rapidly over the last decades and currently are considered as the next-generation technology for many applications, such as organic light-emitting diodes (OLEDs) in flat-panel displays (FPDs) and solid state lighting (SSL), and organic solar cells (OSCs) in clean renewable energy. This dissertation focuses mainly on OLEDs. Although the commercialization of the OLED technology in FPDs is growing and appears to be just around the corner for SSL, there are still several key issues that need to be addressed: (1) the cost of OLEDs is very high, largely due to the costly current manufacturing process; (2) the efficiency of OLEDs needs to be improved. This is vital to the success of OLEDs in the FPD and SSL industries; (3) the lifetime of OLEDs, especially blue OLEDs, is the biggest technical challenge. All these issues raise the demand for new organic materials, new device structures, and continued lower-cost fabrication methods. In an attempt to address these issues, we used solution-processing methods to fabricate highly efficient small molecule OLEDs (SMOLEDs); this approach is costeffective in comparison to the more common thermal vacuum evaporation. We also successfully made efficient indium tin oxide (ITO)-free SMOLEDs to further improve the efficiency of the OLEDs. We employed the spin-dependent optically-detected magnetic resonance (ODMR) technique to study the luminescence quenching processes in OLEDs and organic materials in order to understand the intrinsic degradation mechanisms. We also fabricated polymer LEDs (PLEDs) based on a new electron-accepting blue-emitting polymer and studied the effect of molecular weight on the efficiency of PLEDs. All these studies helped us to better understand the underlying relationship between the organic semiconductor materials and the OLEDs’ performance, and will subsequently assist in further enhancing the efficiency of OLEDs. With strongly improved device performance (in addition to other OLEDs' attributes such as mechanical flexibility and potential low cost), the OLED technology is promising to successfully compete with current technologies, such as LCDs and inorganic LEDs.

Cai, Min

2011-11-30T23:59:59.000Z

255

MAGNETIC NEUTRON SCATTERING  

SciTech Connect (OSTI)

Much of our understanding of the atomic-scale magnetic structure and the dynamical properties of solids and liquids was gained from neutron-scattering studies. Elastic and inelastic neutron spectroscopy provided physicists with an unprecedented, detailed access to spin structures, magnetic-excitation spectra, soft-modes and critical dynamics at magnetic-phase transitions, which is unrivaled by other experimental techniques. Because the neutron has no electric charge, it is an ideal weakly interacting and highly penetrating probe of matter's inner structure and dynamics. Unlike techniques using photon electric fields or charged particles (e.g., electrons, muons) that significantly modify the local electronic environment, neutron spectroscopy allows determination of a material's intrinsic, unperturbed physical properties. The method is not sensitive to extraneous charges, electric fields, and the imperfection of surface layers. Because the neutron is a highly penetrating and non-destructive probe, neutron spectroscopy can probe the microscopic properties of bulk materials (not just their surface layers) and study samples embedded in complex environments, such as cryostats, magnets, and pressure cells, which are essential for understanding the physical origins of magnetic phenomena. Neutron scattering is arguably the most powerful and versatile experimental tool for studying the microscopic properties of the magnetic materials. The magnitude of the cross-section of the neutron magnetic scattering is similar to the cross-section of nuclear scattering by short-range nuclear forces, and is large enough to provide measurable scattering by the ordered magnetic structures and electron spin fluctuations. In the half-a-century or so that has passed since neutron beams with sufficient intensity for scattering applications became available with the advent of the nuclear reactors, they have became indispensable tools for studying a variety of important areas of modern science, ranging from large-scale structures and dynamics of polymers and biological systems, to electronic properties of today's technological materials. Neutron scattering developed into a vast field, encompassing many different experimental techniques aimed at exploring different aspects of matter's atomic structure and dynamics. Modern magnetic neutron scattering includes several specialized techniques designed for specific studies and/or particular classes of materials. Among these are magnetic reflectometry aimed at investigating surfaces, interfaces, and multilayers, small-angle scattering for the large-scale structures, such as a vortex lattice in a superconductor, and neutron spin-echo spectroscopy for glasses and polymers. Each of these techniques and many others offer exciting opportunities for examining magnetism and warrant extensive reviews, but the aim of this chapter is not to survey how different neutron-scattering methods are used to examine magnetic properties of different materials. Here, we concentrate on reviewing the basics of the magnetic neutron scattering, and on the recent developments in applying one of the oldest methods, the triple axis spectroscopy, that still is among the most extensively used ones. The developments discussed here are new and have not been coherently reviewed. Chapter 2 of this book reviews magnetic small-angle scattering, and modern techniques of neutron magnetic reflectometry are discussed in Chapter 3.

ZALIZNYAK,I.A.; LEE,S.H.

2004-07-30T23:59:59.000Z

256

THE EFFECT OF LIMITED SPATIAL RESOLUTION OF STELLAR SURFACE MAGNETIC FIELD MAPS ON MAGNETOHYDRODYNAMIC WIND AND CORONAL X-RAY EMISSION MODELS  

SciTech Connect (OSTI)

We study the influence of the spatial resolution on scales of 5 Degree-Sign and smaller of solar surface magnetic field maps on global magnetohydrodynamic solar wind models, and on a model of coronal heating and X-ray emission. We compare the solutions driven by a low-resolution Wilcox Solar Observatory magnetic map, the same map with spatial resolution artificially increased by a refinement algorithm, and a high-resolution Solar and Heliospheric Observatory Michelson Doppler Imager map. We find that both the wind structure and the X-ray morphology are affected by the fine-scale surface magnetic structure. Moreover, the X-ray morphology is dominated by the closed loop structure between mixed polarities on smaller scales and shows significant changes between high- and low-resolution maps. We conclude that three-dimensional modeling of coronal X-ray emission has greater surface magnetic field spatial resolution requirements than wind modeling, and can be unreliable unless the dominant mixed polarity magnetic flux is properly resolved.

Garraffo, C.; Cohen, O.; Drake, J. J. [Harvard-Smithsonian Center for Astrophysics, 60 Garden St. Cambridge, MA 02138 (United States)] [Harvard-Smithsonian Center for Astrophysics, 60 Garden St. Cambridge, MA 02138 (United States); Downs, C. [Institute for Astronomy, University of Hawaii at Manoa, 2680 Woodlawn Dr., Honolulu, HI 96822 (United States)] [Institute for Astronomy, University of Hawaii at Manoa, 2680 Woodlawn Dr., Honolulu, HI 96822 (United States)

2013-02-10T23:59:59.000Z

257

Method for depositing a uniform layer of particulate material on the surface of an article having interconnected porosity  

DOE Patents [OSTI]

The invention is a method for depositing liquid-suspended particles on an immersed porous article characterized by interconnected porosity. In one form of the invention, coating is conducted in a vessel containing an organic liquid supporting a colloidal dispersion of graphite sized to lodge in surface pores of the article. The liquid comprises a first volatile component (e.g., acetone) and a second less-volatile component (e.g., toluene) containing a dissolved organic graphite-bonding agent. The liquid also contains an organic agent (e.g., cellulose gum) for maintaining the particles in suspension. A porous carbon article to be coated is immersed in the liquid so that it is permeated therewith. While the liquid is stirred to maintain a uniform blend, the vessel headspace is evacuated to effect flashing-off of the first component from the interior of the article. This causes particle-laden liquid exterior of the article to flow inwardly through its surface pores, lodging particles in these pores and forming a continuous graphite coating. The coated article is retrieved and heated to resin-bond the graphite. The method can be used to form a smooth, adherent, continuous coating of various materials on various porous articles. The method is rapid and reproducible.

Wrenn, G.E. Jr.; Lewis, J. Jr.

1982-09-29T23:59:59.000Z

258

Proceedings in Applied Mathematics and Mechanics, 8 April 2008 Locomotion based on the control of the shape of magnetic fluid surfaces  

E-Print Network [OSTI]

Proceedings in Applied Mathematics and Mechanics, 8 April 2008 Locomotion based on the control of the shape of magnetic fluid surfaces and of magnetizable media K. Zimmermann1 , V.A. Naletova 2,3 , I. Zeidis1 , V.A. Turkov3 , V. B¨ohm1 , E. Kolev1 , and J. Popp1 1 Faculty of Mechanical Engineering

Lang, Annika

259

Control of Surface Mounted Permanent Magnet Motors with Special Application to Fractional-Slot Concentrated Windings  

SciTech Connect (OSTI)

It is well known that the ability of the permanent magnet synchronous machine (PMSM) to operate over a wide constant power speed range (CPSR) is dependent upon the machine inductance [1,2,3,4,5]. Early approaches for extending CPSR operation included adding supplementary inductance in series with the motor [1] and the use of anti-parallel thyristor pairs in series with the motor-phase windings [5]. The increased inductance method is compatible with a voltage-source inverter (VSI) controlled by pulse-width modulation (PWM) which is called the conventional phase advance (CPA) method. The thyristor method has been called the dual mode inverter control (DMIC). Neither of these techniques has met with wide acceptance since they both add cost to the drive system and have not been shown to have an attractive cost/benefit ratio. Recently a method has been developed to use fractional-slot concentrated windings to significantly increase the machine inductance [6]. This latest approach has the potential to make the PMSM compatible with CPA without supplemental external inductance. If the performance of such drive is acceptable, then the method may make the PMSM an attractive option for traction applications requiring a wide CPSR. A 30 pole, 6 kW, 6000 maximum revolutions per minute (rpm) prototype of the fractional-slot PMSM design has been developed [7]. This machine has significantly more inductance than is typical of regular PMSMs. The prototype is to be delivered in late 2005 to the Oak Ridge National Laboratory (ORNL) for testing and development of a suitable controller. In advance of the test/control development effort, ORNL has used the PMSM models developed over a number of previous studies to study the steady-state performance of high-inductance PMSM machines with a view towards control issues. The detailed steady-state model developed includes all motor and inverter-loss mechanisms and will be useful in assessing the performance of the dynamic controller to be developed in future work. This report documents the results of this preliminary investigation.

Lawler, J.S.

2005-12-21T23:59:59.000Z

260

Patterned Magnetic Nanostructures and Quantized Magnetic Disks  

E-Print Network [OSTI]

, opens up new opportunities for engineering innovative magnetic materials and devices, developing ultra of magnetic nanostructures as small as 10 nm; 2) engineering of unique magnetic properties (such as domainPatterned Magnetic Nanostructures and Quantized Magnetic Disks STEPHEN Y. CHOU Invited Paper

Note: This page contains sample records for the topic "magnetism materials surface" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


261

Magnetic shielding  

DOE Patents [OSTI]

A magnetically-conductive filler material bridges the gap between a multi-part magnetic shield structure which substantially encloses a predetermined volume so as to minimize the ingress or egress of magnetic fields with respect to that volume. The filler material includes a heavy concentration of single-magnetic-domain-sized particles of a magnetically conductive material (e.g. soft iron, carbon steel or the like) dispersed throughout a carrier material which is generally a non-magnetic material that is at least sometimes in a plastic or liquid state. The maximum cross-sectional particle dimension is substantially less than the nominal dimension of the gap to be filled. An epoxy base material (i.e. without any hardening additive) low volatility vacuum greases or the like may be used for the carrier material. The structure is preferably exposed to the expected ambient field while the carrier is in a plastic or liquid state so as to facilitate alignment of the single-magnetic-domain-sized particles with the expected magnetic field lines.

Kerns, J.A.; Stone, R.R.; Fabyan, J.

1985-02-12T23:59:59.000Z

262

Intrinsic Surface Stability in LiMn2-xNix04-s (x = 0.45, 0.5) High Voltage Spinel Materials for Lithium Ion Batteries  

SciTech Connect (OSTI)

This work reports the surface stability of the high vollage Li ion cathode LiMn2_,Ni,Ooh\\ (x = 0.5, 0.45) by comparing thin fi lm and powder composite electrodes after cycling using X-ray photoelectron spectroscopy. The thin film electrodes offer the abili ty to probe the surface of the material without the need of a conductive agent and polymer binder typically used in composite electrodes. The resulls suggest that neither oxidation of PP6 to POF3 nor the decomposition of ethylene carbonate or dimethylene carbonate occurs on the surface of the spinel material. These resulls confirm the enhanced cycling stability and rate capability associated with the high vollage spinel material and suggests that the SE!IIayer fonns due to the reaction of electrochemically inactive components in composite electrodes with the electrolyte.

Carroll, Kyler J [University of California, San Diego; Yang, Ming-Che [University of Florida, Gainesville; Veith, Gabriel M [ORNL; Dudney, Nancy J [ORNL; Meng, Ying Shirley [University of California, San Diego

2012-01-01T23:59:59.000Z

263

Journal of Magnetism and Magnetic Materials 272276 (2004) e1333e1334 Non-local Hall resistance measured in submicron-scale  

E-Print Network [OSTI]

succeeded in detecting the spin- accumulation signal in the normal metal by the non- local spin-valve-related phenomenon like a spin-valve effect. When the spin-polarized electrons accumulate in a non-magnetic metal coefficient of 8:40 Ã? 10Ã?11 A=cm3 ; indicating the effect of the stray filed from the ferromagnetic layer

Otani, Yoshichika

264

Microporous Magnets  

SciTech Connect (OSTI)

Combining porosity and magnetic ordering in a single material presents a significant challenge since magnetic exchange generally requires short bridges between the spin carriers, whereas porosity usually relies on the use of long diamagnetic connecting ligands. Despite this apparent incompatibility, notable successes have been achieved of late in generating truly microporous solids with high magnetic ordering temperatures. In this critical review, we give an overview of this emerging class of multifunctional materials, with particular emphasis on synthetic strategies and possible routes to new materials with improved properties (149 references).

Dechambenoit, Pierre; Long, Jeffrey R.

2011-01-01T23:59:59.000Z

265

Magnetic investigations  

SciTech Connect (OSTI)

Air and ground magnetic anomalies in the Climax stock area of the NTS help define the gross configuration of the stock and detailed configuration of magnetized rocks at the Boundary and Tippinip faults that border the stock. Magnetizations of geologic units were evaluated by measurements of magnetic properties of drill core, minimum estimates of magnetizations from ground magnetic anomalies for near surface rocks, and comparisons of measured anomalies with anomalies computed by a three-dimensional forward program. Alluvial deposits and most sedimentary rocks are nonmagnetic, but drill core measurements reveal large and irregular changes in magnetization for some quartzites and marbles. The magnetizations of quartz monzonite and granodiorite near the stock surface are weak, about 0.15 A/m, and increase at a rate of 0.00196 A/m/m to 1.55 A/m, at depths greater than 700 m (2300 ft). The volcanic rocks of the area are weakly magnetized. Aeromagnetic anomalies 850 m (2800 ft) above the stock are explained by a model consisting of five vertical prisms. Prisms 1, 2, and 3 represent the near surface outline of the stock, prism 4 is one of the models developed by Whitehill (1973), and prism 5 is modified from the model developed by Allingham and Zietz (1962). Most of the anomaly comes from unsampled and strongly-magnetized deep sources that could be either granite or metamorphosed sedimentary rocks. 48 refs., 23 figs., 3 tabs.

Bath, G.D.; Jahren, C.E.; Rosenbaum, J.G. [Geological Survey, Denver, CO (USA); Baldwin, M.J. [Fenix and Scisson, Inc., Mercury, NV (USA)

1983-12-31T23:59:59.000Z

266

SURFACE SCIENCE, WETTING, CONDENSATION, ENGINEERED Correspondence and requests for materials: konradr@asu.edu and varanasi@mit.edu  

E-Print Network [OSTI]

coefficients has potential for efficiency enhancements. Here we investigate condensation behavior of a variety of fluids with high or moderate surface tension27­31 or Marangoni dropwise condensation of binary mixtures1 SURFACE SCIENCE, WETTING, CONDENSATION, ENGINEERED SURFACES Correspondence and requests

267

Magnetic nanotubes  

DOE Patents [OSTI]

A magnetic nanotube includes bacterial magnetic nanocrystals contacted onto a nanotube which absorbs the nanocrystals. The nanocrystals are contacted on at least one surface of the nanotube. A method of fabricating a magnetic nanotube includes synthesizing the bacterial magnetic nanocrystals, which have an outer layer of proteins. A nanotube provided is capable of absorbing the nanocrystals and contacting the nanotube with the nanocrystals. The nanotube is preferably a peptide bolaamphiphile. A nanotube solution and a nanocrystal solution including a buffer and a concentration of nanocrystals are mixed. The concentration of nanocrystals is optimized, resulting in a nanocrystal to nanotube ratio for which bacterial magnetic nanocrystals are immobilized on at least one surface of the nanotubes. The ratio controls whether the nanocrystals bind only to the interior or to the exterior surfaces of the nanotubes. Uses include cell manipulation and separation, biological assay, enzyme recovery, and biosensors.

Matsui, Hiroshi (Glen Rock, NJ); Matsunaga, Tadashi (Tokyo, JP)

2010-11-16T23:59:59.000Z

268

Practical Materials for Heavy Metal Ion Chelation: PolyethylenimPractical Materials for Heavy Metal Ion Chelation: Polyethyleniminesines tailored onto The Surface oftailored onto The Surface of Porous SilicaPorous Silica  

E-Print Network [OSTI]

Practical Materials for Heavy Metal Ion Chelation: PolyethylenimPractical Materials for Heavy Metal *presenting author INTRODUCTION As a result of heavy metal ion release from industrial wastewater, water pollution has become a serious problem. Waste streams contain solutions of metal ions, such as copper

Taralp, Alpay

269

Nuclear magnetic resonance: Its role as a microscopic probe of the electronic and magnetic properties of High-{Tc} superconductors and related materials  

SciTech Connect (OSTI)

NMR experiments are reported for Sr{sub 2}CuO{sub 2}Cl{sub 2}, HgBa{sub 2}CuO{sub 4+d}, YNi{sub 2}B{sub 2}C and YBa{sub 2}Cu{sub 3}O{sub 7}. NMR studies typify three different aspects of microscopic properties of HTSC. In non-superconducting antiferromagnetic (AF) prototype Sr{sub 2}CuO{sub 2}Cl{sub 2}, we used NMR to investigate Cu{sup 2+} correlated spin dynamics and AF phase transition in CuO2 layers. In the superconductors, we used NMR both to investigate the electronic properties of the Fermi-liquid in normal and superconducting states and to investigate flux lattice and flux-line dynamics in the superconducting state in presence of magnetic field. A summary of each study is given: {sup 35}Cl NMR was measured in Sr{sub 2}CuO{sub 2}Cl{sub 2} single crystals with T{sub N}=257K. {sub 35}Cl NMR relaxation rates showed crossover of Cu{sup 2+} spin dynamics from Heisenberg to XY-like correlation at 290 K well above T{sub N}. A field-dependent T{sub N} for H{perpendicular}c was observed and explained by a field-induced Ising-like anisotropy in ab plane. {sup 199}Hg NMR was measured in HgBa{sub 2}CuO{sub 4+d}. Properties of the Fermi-liquid are characterized by a single-spin fluid picture and opening of a spin pseudo-gap at q=0 above {Tc}. Below {Tc}, spin component of Knight shift decreases rapidly in agreement with prediction for d-wave pairing scheme. {sup 11}B and {sup 89}Y NMR/magnetization were measured in YNi{sub 2}B{sub 2}C. Temperature dependence of {sup 11}B Knight shift and of the NSLR gave a normal state which agrees with the Korringa relation, indicating that the AF fluctuations on the Ni sublattice are negligible. Opening of the superconducting gap obeys BCS. A NMR approach to investigate vortex thermal motion in HTSC is presented, based on contribution of thermal flux-lines motion to both T{sub 2}{sup {minus}1} and T{sub 1}{sup {minus}1}. Effects are demonstrated in YBa{sub 2}Cu{sub 3}O{sub 7} and HgBa{sub 2}CuO{sub 4+d}.

Suh, Byoung Jin

1995-12-27T23:59:59.000Z

270

Magnetorheological materials, method for making, and applications thereof  

SciTech Connect (OSTI)

A magnetorheological material comprises a magnetic particle and a ceramic material, wherein the magnetorheological material is in a dried form and further wherein a portion of the ceramic material is in the form of a nanocrystalline coating over the entire exterior surface of the magnetic particle and another portion of the ceramic material is in the form of a free nanocrystal. A magnetorheological material comprises a magnetic particle having a ceramic material coating over an external surface thereof as a result of a coating process, and a free nanocrystal of the ceramic material in the form of a residual by-product of the coating process. A sol-gel process for making a magnetorheological product comprises providing a sol of a desired ceramic coating material; combining a desired quantity of carbonyl iron (CI) particles with the sol to coat the CI particles with the ceramic coating material; creating a resulting quantity of nanocrystalline ceramic material-coated CI particles and a quantity of free nanocrystals of the ceramic material; and, drying the resulting quantity of coated CI particles and free nanocrystals to a moisture content equal to or less than 2 wt %.

Shen, Rui; Yang, Hong; Shafrir, Shai N.; Miao, Chunlin; Wang, Mimi; Mici, Joni; Lambropoulos, John C.; Jacobs, Stephen D.

2014-08-19T23:59:59.000Z

271

Photoemission Spectroscopy of Magnetic and Nonmagnetic Impurities on the Surface of the Bi2Se3 Topological Insulator  

E-Print Network [OSTI]

Topological Insulator T. Valla,1,* Z.-H. Pan,1 D. Gardner,2 Y. S. Lee,2 and S. Chu3 1 Condensed Matter Physics; published 12 March 2012) Dirac-like surface states on surfaces of topological insulators have a chiral spin impurities on the surface of Bi2Se3, a model topological insulator. We reveal a remarkable insensitivity

Ohta, Shigemi

272

A model for materials scientists: Water runs off the surface of a lotus leaf without a trace. Researchers  

E-Print Network [OSTI]

to the annoying smears on window panes, it could also make it possible to produce self-cleaning solar panels the annoying smeary film that gets left behind. Reliably self-cleaning MATERIAL & TECHNOLOGY

273

Multiscale Studies of the Formation and Stability of Surface-based Nanostructures, DOE Computational Materials Science Network - Final Report  

SciTech Connect (OSTI)

Summary of work performed under DOE-CMSN/FG0205ER46227, Multiscale Studies of the Formation and Stability of Surface-based Nanostructures, listing publications, collaborations, and presentations.

Einstein, Theodore L.

2011-10-31T23:59:59.000Z

274

Surface loss probability of atomic hydrogen for different electrode cover materials investigated in H{sub 2}-Ar low-pressure plasmas  

SciTech Connect (OSTI)

In an inductively coupled H{sub 2}-Ar plasma at a total pressure of 1.5?Pa, the influence of the electrode cover material on selected line intensities of H, H{sub 2}, and Ar are determined by optical emission spectroscopy and actinometry for the electrode cover materials stainless steel, copper, tungsten, Macor{sup ®}, and aluminum. Hydrogen dissociation degrees for the considered conditions are determined experimentally from the measured emission intensity ratios. The surface loss probability ?{sub H} of atomic hydrogen is correlated with the measured line intensities, and ?{sub H} values are determined for the considered materials. Without the knowledge of the atomic hydrogen temperature, ?{sub H} cannot be determined exactly. However, ratios of ?{sub H} values for different surface materials are in first order approximation independent of the atomic hydrogen temperature. Our results show that ?{sub H} of copper is equal to the value of stainless steel, ?{sub H} of Macor{sup ®} and tungsten is about 2 times smaller and ?{sub H} of aluminum about 5 times smaller compared with stainless steel. The latter ratio is in reasonable agreement with literature. The influence of the atomic hydrogen temperature T{sub H} on the absolute value is thoroughly discussed. For our assumption of T{sub H}?=?600?K, we determine a ?{sub H} for stainless steel of 0.39?±?0.13.

Sode, M., E-mail: maik.sode@ipp.mpg.de; Schwarz-Selinger, T.; Jacob, W. [Max-Planck-Institut für Plasmaphysik, Boltzmannstraße 2, D-85748 Garching (Germany); Kersten, H. [Institute for Experimental and Applied Physics, Christian-Albrechts-Universität zu Kiel, Leibnizstraße 11-19, D-24098 Kiel (Germany)

2014-07-07T23:59:59.000Z

275

Laser Ablation Sampling of Materials Directly into the Formed Liquid Microjunction of a Continuous Flow Surface Sampling Probe/Electrospray Ionization Emitter for Mass Spectral Analysis and Imaging  

SciTech Connect (OSTI)

Transmission geometry laser ablation directly into a formed liquid microjunction of a continuous flow liquid microjunction surface sampling probe/electrospray ionization emitter was utilized for molecular and elemental detection and mass spectrometry imaging. The ability to efficiently capture and ionize ablated material was demonstrated by the detection of various small soluble n-mers of polyaniline and silver ion solvent clusters formed from laser ablation of electropolymerized polyaniline and silver thin films, respectively. In addition, analysis of surfaces that contain soluble components was accomplished by coating or laminating the sample with an insoluble film to enable liquid junction formation without directly extracting material from the surface. The ability to perform mass spectrometry imaging at a spatial resolution of about 50 m was illustrated by using laminated inked patterns on a microscope slide. In general, these data demonstrate at least an order of magnitude signal enhancement compared to the non-contact, laser ablation droplet capture-based surface sampling/ionization approaches that have been previously presented.

Ovchinnikova, Olga S [ORNL] [ORNL; Lorenz, Matthias [ORNL] [ORNL; Kertesz, Vilmos [ORNL] [ORNL; Van Berkel, Gary J [ORNL] [ORNL

2013-01-01T23:59:59.000Z

276

Magnetically attached sputter targets  

DOE Patents [OSTI]

An improved method and assembly for attaching sputtering targets to cathode assemblies of sputtering systems which includes a magnetically permeable material is described. The magnetically permeable material is imbedded in a target base that is brazed, welded, or soldered to the sputter target, or is mechanically retained in the target material. Target attachment to the cathode is achieved by virtue of the permanent magnets and/or the pole pieces in the cathode assembly that create magnetic flux lines adjacent to the backing plate, which strongly attract the magnetically permeable material in the target assembly. 11 figures.

Makowiecki, D.M.; McKernan, M.A.

1994-02-15T23:59:59.000Z

277

Magnetic nanohole superlattices  

DOE Patents [OSTI]

A magnetic material is disclosed including a two-dimensional array of carbon atoms and a two-dimensional array of nanoholes patterned in the two-dimensional array of carbon atoms. The magnetic material has long-range magnetic ordering at a temperature below a critical temperature Tc.

Liu, Feng

2013-05-14T23:59:59.000Z

278

Ch 20. Magnetism Liu UCD Phy1B 2012 1  

E-Print Network [OSTI]

Ch 20. Magnetism Liu UCD Phy1B 2012 1 #12;I. MagnetI. Magnet Poles of a magnet: magnetic effect is strongest When the magnet is freely suspended North pole: pointing to north South pole: pointing to south Poles always come in pairs Liu UCD Phy1B 2012 2 #12;Magnetic MaterialsMagnetic Materials Magnetite Fe3O4

Yoo, S. J. Ben

279

Temperature-dependent tensile strength, surface roughness diagnostics, and magnetic support and positioning of polymer ICF shells. Final report, October 1, 1993--April 30, 1995  

SciTech Connect (OSTI)

During the course of this grant, we perfected emissivity and accommodation coefficient measurements on polymer ICF shells in the temperature range 250 to 350 K. Values for polystyrene shells are generally between 10{sup -2} and 10{sup -3}, which are very advantageous for ICF at cryogenic temperatures. Preliminary results on Br doped target shells indicate an accommodation coefficient, presumably associated with surface roughness on an atomic scale, about an order of magnitude larger than for ordinary polystyrene target shells. We also constructed apparatus with optical access for low temperature tensile strength and emissivity measurements, and made preliminary tests on this system. Magnetic shells were obtained both from GDP coating and from doping styrene with 10 manometer size ferromagnetic particles. The magnetic properties were measured through electron spin resonance (ESR). These experiments confirm the applicability of the Curie law, and establish the validity of using ESR measurements to determine shell temperature in the low temperature regime from 4K to 250K, thus complementing our presently accessible range. The high electron spin densities (> 10{sup 20}/CM{sup 3}) suggest magnetic levitation should be feasible at cryogenic temperatures. This work has resulted in two conference presentations, a Technical Report, a paper to be published in Fusion Technology, and a Master`s Thesis.

Honig, A.

1995-12-15T23:59:59.000Z

280

NANOSCALE STRUCTURALAND MAGNETIC CHARACTERIZATION USING  

E-Print Network [OSTI]

by magnetic materials as their dimensions are reduced towards the nanoscale. Important examples include coupling between magnetic thin films, which depends on the thickness of the non-magnetic spacer layer [2

Dunin-Borkowski, Rafal E.

Note: This page contains sample records for the topic "magnetism materials surface" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


281

Ames Lab 101: Magnetic Refrigeration  

ScienceCinema (OSTI)

Vitalij Pecharsky, distinguished professor of materials science and engineering, discusses his research in magnetic refrigeration at Ames Lab.

Pecharsky, Vitalij

2013-03-01T23:59:59.000Z

282

Multi-Instrument Characterization of the Surfaces and Materials in Microfabricated, Carbon Nanotube-Templated Thin Layer Chromatography Plates. An Analogy to ‘The Blind Men and the Elephant’  

SciTech Connect (OSTI)

Herein we apply a suite of surface/materials analytical tools to characterize some of the materials created in the production of microfabricated thin layer chromatography plates. Techniques used include X-ray photoelectron spectroscopy (XPS), valence band spectroscopy, static time-of-flight secondary ion spectrometry (ToF-SIMS) in both positive and negative ion modes, Rutherford backscattering spectroscopy (RBS), and helium ion microscopy (HIM). Materials characterized include: the Si(100) substrate with native oxide: Si/SiO2, alumina (35 nm) deposited as a diffusion barrier on the Si/SiO2: Si/SiO2/Al2O3, iron (6 nm) thermally evaporated on the Al2O3: Si/SiO2/Al2O3/Fe, the iron film annealed in H2 to make Fe catalyst nanoparticles: Si/SiO2/Al2O3/Fe(NP), and carbon nanotubes (CNTs) grown from the Fe nanoparticles: Si/SiO2/Al2O3/Fe(NP)/CNT. The Fe thin films and nanoparticles are found in an oxidized state. Some of the analyses of the CNTs/CNT forests reported appear to be unique: the CNT forest appears to exhibit an interesting ‘channeling’ phenomenon by RBS, we observe an odd-even effect in the ToF-SIMS spectra of Cn- species for n = 1 – 6, with ions at even n showing greater intensity than the neighboring signals, and ions with n ? 6 showing a steady decrease in intensity, and valence band characterization of CNTs using X-radiation is reported. The information obtained from the combination of the different analytical tools provides a more complete understanding of our materials than a single technique, which is analogous to the story of ‘The Blind Men and the Elephant’. (Of course there is increasing emphasis on the use of multiple characterization tools in surface and materials analysis.) The raw XPS and ToF-SIMS spectra from this study will be submitted to Surface Science Spectra for archiving.

Jensen, David S.; Kanyal, Supriya S.; Madaan, Nitesh; Hancock, Jared M.; Dadson, Andrew; Vail, Michael A.; Vanfleet, Richard; Shutthanandan, V.; Zhu, Zihua; Engelhard, Mark H.; Linford, Matthew R.

2013-08-08T23:59:59.000Z

283

Photoelectron spectroscopic study of the surface reactivity of the high T[c] material YBa?Cu?O?  

E-Print Network [OSTI]

. II. EXPERIMENTAL. 2. 1. Sample preparation and cleaning. 2. 2. Plasma treatments. 2. 3. XPS and Auger spectroscopy. 2. 4. Experimental procedures. III. RESULTS AND DISCUSSIONS. 3. 1. Effect of surface contamination. . 3. 2. Effect of thermal..., Johnson et al 1987 and Onellion et al 1987), and a valence-band which is composed of hybridized Cu 3d and 0 2p levels located below the E~ (Kurtz et al 1987). Some XPS and Auger spectra have been taken by several groups. Temperature-dependent changes...

Liu, Hong-Xia

1988-01-01T23:59:59.000Z

284

Wind tunnel simulation of wind effects and associated displacement hazards on flat surface construction materials such as plywood  

E-Print Network [OSTI]

and converted to velocity using the dynamic pressure conversion equation (developed in Appendix A) Q I = 0. 00256 V (2) The individual pressures measured at the ports were averaged across the area represented by each port to yield an integrated pressure... layer undergoes a transition to turbulent. The Reynolds number for laminar flow on a flat plate varies from approximately 3. 2 x 10' to 3. 0 x 10 depending on the relative smoothness of the plate surface [Parker, 1974]. The data for these tests were...

Madeley, Jack T.

1996-01-01T23:59:59.000Z

285

Magnetic gripper device  

DOE Patents [OSTI]

A climbing apparatus is provided for climbing ferromagnetic surfaces, such as storage tanks and steel frame structures. A magnet assembly is rotatably mounted in a frame assembly. The frame assembly provides a pair of cam surfaces having different dimensions so that, when the frame is rotated, the cam surfaces contact the ferromagnetic surface to separate the magnet assembly from the surface. The different cam dimensions enable one side of the magnet at a time to be detached from the surface to reduce the effort needed to disengage the climbing apparatus. The cam surface also provides for smoothly attaching the apparatus. A hardened dowel pin is also attached to the frame and the pointed end of the dowel engages the surface when the magnet is attached to the surface to prevent downward sliding movement of the assembly under the weight of the user.

Meyer, R.E.

1993-03-09T23:59:59.000Z

286

Magnetic gripper device  

DOE Patents [OSTI]

A climbing apparatus is provided for climbing ferromagnetic surfaces, such as storage tanks and steel frame structures. A magnet assembly is rotatably mounted in a frame assembly. The frame assembly provides a pair of cam surfaces having different dimensions so that, when the frame is rotated, the cam surfaces contact the ferromagnetic surface to separate the magnet assembly from the surface. The different cam dimensions enable one side of the magnet at a time to be detached from the surface to reduce the effort needed to disengage the climbing apparatus. The cam surface also provides for smoothly attaching the apparatus. A hardened dowel pin is also attached to the frame and the pointed end of the dowel engages the surface when the magnet is attached to the surface to prevent downward sliding movement of the assembly under the weight of the user.

Meyer, Ross E. (Los Alamos, NM)

1993-01-01T23:59:59.000Z

287

Overlap Technique for End-Cap Seals on Cylindrical Magnetic Shields  

E-Print Network [OSTI]

We present results from studies of the effectiveness of an overlap technique for forming a magnetic seal across a gap at the boundary between a cylindrical magnetic shield and an end-cap. In this technique a thin foil of magnetic material overlaps the two surfaces, thereby spanning the gap across the cylinder and the end-cap, with the magnetic seal then formed by clamping the thin magnetic foil to the surfaces of the cylindrical shield and the end-cap on both sides of the gap. In studies with a prototype 31-cm diameter, 91-cm long, 0.16-cm thick cylindrical magnetic shield and flared end-cap, the magnetic shielding performance of our overlap technique is comparable to that obtained with the conventional method in which the end-cap is placed in direct lapped contact with the cylindrical shield via through bolts or screws.

Malkowski, S; Boissevain, J; Daurer, C; Filippone, B W; Hona, B; Plaster, B; Woods, D; Yan, H

2013-01-01T23:59:59.000Z

288

Iron porphyrin polymer films: Materials for the modification of electrode surfaces and the detection of nitric oxide  

SciTech Connect (OSTI)

We are currently investigating a new method for the detection and quantification of nitric oxide (NO) based on a carbon electrode chemically modified with an iron porphyrin polymer film. Commercially available vinyl-substituted iron porphyrin monomers can be polymerized directly onto electrode surfaces through a published electrochemical polymerization process. We are also developing a synthesis for a new vinyl-substituted monomer, iron 5,10,15-triphenyl-20-vinyl porphyrin chloride, in hopes of improving polymer film stability. The electrochemistry of NO is also being investigated at electrodes chemically modified with an iron porphyrin polymer film. We are studying the catalytic oxidation of iron porphyrin bound NO to nitrate by molecular oxygen. The reaction with molecular oxygen is preceded by a one electron reduction of the iron porphyrin-NO complex. If currents proportional to nitric oxide concentration can be measured, a new NO electrochemical sensor will be designed.

McGuire, M.; Drew, S.M. [Carleton College, Northfield, MN (United States)

1996-10-01T23:59:59.000Z

289

Flipping the switch on magnetism in strontium titanate  

Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

Flipping the switch on magnetism in strontium titanate Flipping the switch on magnetism in strontium titanate Researchers have found a way to magnetize this material using light,...

290

Microstructure of TiB{sub 2}/carbon steel surface-alloyed materials fabricated by high-energy electron beam irradiation  

SciTech Connect (OSTI)

The processing and the microstructural analysis of TiB{sub 2}/carbon steel surface-alloyed materials using the irradiation of a high-energy electron beam were investigated in this study. The mixtures of TiB{sub 2} powders and flux were deposited on a plain carbon steel substrate, and then electron beam was irradiated on these mixtures using an electron beam accelerator. The microstructure of the irradiated surface layer was composed of a melted region, an interfacial region, a coarse-grained heat-affected zone (HAZ), and a fine-grained HAZ. A few residual micropores were found in the melted region of the specimen processed without flux because of irregular thermal transfer, but their number was decreased in the specimens processed with a considerable amount of flux. As a result of irradiation, the Ti content was homogeneously maintained throughout the melted region, whose hardness was greatly improved. This was associated with the microstructural modification including the segregation of Ti and B along solidification cell boundaries and the formation of fine Ti(C, N) particles. The proper flux mix ratio was 15 to 30% to obtain excellent surface alloying and a homogeneous microstructure.

Euh, K. Lee, S.; Shin, K.

1999-12-01T23:59:59.000Z

291

Vacuum properties of sintered SmCo/sub 5/ magnets  

SciTech Connect (OSTI)

There are many desirable applications of powerful, rare-earth permanent magnets made of sintered SmCo/sub 5/ material within vacuum systems. One application is the use of large numbers of SmCo/sub 5/ magnets to provide the undulating magnetic field in a free-electron-laser wiggler structure. Tests were conducted at Los Alamos to determine the suitability of SmCo/sub 5/ magnets in a vacuum environment of approx. 10/sup -6/ torr. The vacuum performances of the wiggler system, with and without the SmCo/sub 5/ magnets (having approx. 11% of the total surface area) installed, were essentially identical. These tests indicate that SmCo/sub 5/ magnets have good vacuum properties and are suitable for use in many vacuum systems.

Warren, R.W.; DePaula, R.F.; Hansborough, L.D.

1981-12-01T23:59:59.000Z

292

Status of Magnetic Nozzle and Plasma Detachment Experiment  

SciTech Connect (OSTI)

High power plasma propulsion can move large payloads for orbit transfer, lunar missions, and beyond with large savings in fuel consumption owing to the high specific impulse. At high power, lifetime of the thruster becomes an issue. Electrodeless devices with magnetically guided plasma offer the advantage of long life since magnetic fields confine the plasma radially and keep it from impacting the material surfaces. For decades, concerns have been raised about the plasma remaining attached to the magnetic field and returning to the vehicle along the closed magnetic field lines. Recent analysis suggests that this may not be an issue if the magnetic field is properly shaped in the nozzle region and the plasma has sufficient energy density to stretch the magnetic field downstream. An experiment is being performed to test the theory regarding the MHD detachment scenario. The status of that experiment will be discussed in this paper.

Chavers, D. Gregory; Dobson, Chris; Jones, Jonathan; Lee, Michael; Martin, Adam; Gregory, Judith; Cecil, Jim [Propulsion Research Center, MSFC NASA, Huntsville, AL 35812 (United States); Bengtson, Roger D.; Breizman, Boris; Arefiev, Alexey [Department of Physics, University of Texas at Austin, TX 78712 (United States); Institute of Fusion Studies, University of Texas at Austin, TX 78712 (United States); Chang-Diaz, Franklin; Squire, Jared; Glover, Tim; McCaskill, Greg [Ad Astra Rocket Company, 2101 NASA Parkway, Houston, TX 77058 (United States); Cassibry, Jason; Li Zhongmin [University of Alabama in Huntsville, Huntsville, AL 35899 (United States)

2006-01-20T23:59:59.000Z

293

Controlled interface profile in SmCo/Fe exchange-spring magnets Materials Science Division, Argonne National Laboratory, Argonne, Illinois 60439  

E-Print Network [OSTI]

-spring permanent magnets enhances the exchange coupling effectiveness without modifying the local composition are complementary or even mutually exclusive. Exchange-spring nanocomposite magnets1,2 consist of exchange coupled of the exchange-spring magnets. For example, interfacial condi- tions influence the exchange coupling

Liu, J. Ping

294

Irreversible Thermodynamics and Smart Materials Systems Modelling. Example of  

E-Print Network [OSTI]

Irreversible Thermodynamics and Smart Materials Systems Modelling. Example of Magnetic Shape Memory mechanisms in smart materials. This procedure is applied to Magnetic Shape Memory Alloys actuators of complex active materials for smart systems. Keywords: Smart material systems, Actuator design

Paris-Sud XI, Université de

295

Experimental Design for a Sponge-Wipe Study to Relate the Recovery Efficiency and False Negative Rate to the Concentration of a Bacillus anthracis Surrogate for Six Surface Materials  

SciTech Connect (OSTI)

Two concerns were raised by the Government Accountability Office following the 2001 building contaminations via letters containing Bacillus anthracis (BA). These included the: 1) lack of validated sampling methods, and 2) need to use statistical sampling to quantify the confidence of no contamination when all samples have negative results. Critical to addressing these concerns is quantifying the probability of correct detection (PCD) (or equivalently the false negative rate FNR = 1 ? PCD). The PCD/FNR may depend on the 1) method of contaminant deposition, 2) surface concentration of the contaminant, 3) surface material being sampled, 4) sample collection method, 5) sample storage/transportation conditions, 6) sample processing method, and 7) sample analytical method. A review of the literature found 17 laboratory studies that focused on swab, wipe, or vacuum samples collected from a variety of surface materials contaminated by BA or a surrogate, and used culture methods to determine the surface contaminant concentration. These studies quantified performance of the sampling and analysis methods in terms of recovery efficiency (RE) and not PCD/FNR (which left a major gap in available information). Quantifying the PCD/FNR under a variety of conditions is a key aspect of validating sample and analysis methods, and also for calculating the confidence in characterization or clearance decisions based on a statistical sampling plan. A laboratory study was planned to partially fill the gap in PCD/FNR results. This report documents the experimental design developed by Pacific Northwest National Laboratory and Sandia National Laboratories (SNL) for a sponge-wipe method. The study will investigate the effects on key response variables from six surface materials contaminated with eight surface concentrations of a BA surrogate (Bacillus atrophaeus). The key response variables include measures of the contamination on test coupons of surface materials tested, contamination recovered from coupons by sponge-wipe samples, RE, and PCD/FNR. The experimental design involves 16 test runs, to be performed in two blocks of eight runs. Three surface materials (stainless steel, vinyl tile, and ceramic tile) were tested in the first block, while three other surface materials (plastic, painted wood paneling, and faux leather) will be tested in the second block. The eight surface concentrations of the surrogate were randomly assigned to test runs within each block. Some of the concentrations will be very low and may present challenges for deposition, sampling, and analysis. However, such tests are needed to investigate RE and PCD/FNR over the full range of concentrations of interest. In each run, there will be 10 test coupons of each of the three surface materials. A positive control sample will be generated prior to each test sample. The positive control results will be used to 1) calculate RE values for the wipe sampling and analysis method, and 2) fit RE- and PCD-concentration equations, for each of the six surface materials. Data analyses will support 1) estimating the PCD for each combination of contaminant concentration and surface material, 2) estimating the surface concentrations and their uncertainties of the contaminant for each combination of concentration and surface material, 3) estimating RE (%) and their uncertainties for each combination of contaminant concentration and surface material, 4) fitting PCD-concentration and RE-concentration equations for each of the six surface materials, 5) assessing goodness-of-fit of the equations, and 6) quantifying the uncertainty in PCD and RE predictions made with the fitted equations.

Piepel, Gregory F.; Amidan, Brett G.; Krauter, Paula; Einfeld, Wayne

2010-12-16T23:59:59.000Z

296

Experimental Design for a Sponge-Wipe Study to Relate the Recovery Efficiency and False Negative Rate to the Concentration of a Bacillus anthracis Surrogate for Six Surface Materials  

SciTech Connect (OSTI)

Two concerns were raised by the Government Accountability Office following the 2001 building contaminations via letters containing Bacillus anthracis (BA). These included the: 1) lack of validated sampling methods, and 2) need to use statistical sampling to quantify the confidence of no contamination when all samples have negative results. Critical to addressing these concerns is quantifying the false negative rate (FNR). The FNR may depend on the 1) method of contaminant deposition, 2) surface concentration of the contaminant, 3) surface material being sampled, 4) sample collection method, 5) sample storage/transportation conditions, 6) sample processing method, and 7) sample analytical method. A review of the literature found 17 laboratory studies that focused on swab, wipe, or vacuum samples collected from a variety of surface materials contaminated by BA or a surrogate, and used culture methods to determine the surface contaminant concentration. These studies quantified performance of the sampling and analysis methods in terms of recovery efficiency (RE) and not FNR (which left a major gap in available information). Quantifying the FNR under a variety of conditions is a key aspect of validating sample and analysis methods, and also for calculating the confidence in characterization or clearance decisions based on a statistical sampling plan. A laboratory study was planned to partially fill the gap in FNR results. This report documents the experimental design developed by Pacific Northwest National Laboratory and Sandia National Laboratories (SNL) for a sponge-wipe method. The testing was performed by SNL and is now completed. The study investigated the effects on key response variables from six surface materials contaminated with eight surface concentrations of a BA surrogate (Bacillus atrophaeus). The key response variables include measures of the contamination on test coupons of surface materials tested, contamination recovered from coupons by sponge-wipe samples, RE, and FNR. The experimental design involves 16 test runs, performed in two blocks of eight runs. Three surface materials (stainless steel, vinyl tile, and ceramic tile) were tested in the first block, while three other surface materials (plastic, painted wood paneling, and faux leather) were tested in the second block. The eight surface concentrations of the surrogate were randomly assigned to test runs within each block. Some of the concentrations were very low and presented challenges for deposition, sampling, and analysis. However, such tests are needed to investigate RE and FNR over the full range of concentrations of interest. In each run, there were 10 test coupons of each of the three surface materials. A positive control sample was generated at the same time as each test sample. The positive control results will be used to 1) calculate RE values for the wipe sampling and analysis method, and 2) fit RE- and FNR-concentration equations, for each of the six surface materials. Data analyses will support 1) estimating the FNR for each combination of contaminant concentration and surface material, 2) estimating the surface concentrations and their uncertainties of the contaminant for each combination of concentration and surface material, 3) estimating RE (%) and their uncertainties for each combination of contaminant concentration and surface material, 4) fitting FNR-concentration and RE-concentration equations for each of the six surface materials, 5) assessing goodness-of-fit of the equations, and 6) quantifying the uncertainty in FNR and RE predictions made with the fitted equations.

Piepel, Gregory F.; Amidan, Brett G.; Krauter, Paula; Einfeld, Wayne

2011-05-01T23:59:59.000Z

297

Contol of Surface Mounted Permanent Magnet Motors with Special Application to Motors with Fractional-Slot Concentrated Windings  

SciTech Connect (OSTI)

A 30-pole, 6-kW prototype of a fractional-slot permanent magnet synchronous motor (PMSM) design has been developed to operate at a maximum speed of 6000 rpm [1,2]. This machine has significantly more inductance than regular PMSMs with distributed windings. The prototype was delivered in April 2006 to the Oak Ridge National Laboratory (ORNL) for testing and development of a suitable controller. To prepare for this test/control development effort, ORNL used PMSM models developed over a number of previous studies to preview the control issues that arise when a dynamic controller drives a high inductance PMSM machine during steady state performance evaluations. The detailed steady state model developed includes all motor and inverter loss mechanisms and was useful for assessing the performance of the dynamic controller before it was put into operation. This report documents the results of tests demonstrating the effectiveness of ORNL's simple low-cost control scheme during characterization of the fractional-slot concentrated windings (FSCW) PMSM motor. The control scheme is simple because only the supply voltage magnitude and the phase angle between the back-electromotive force (emf) and the supply voltage is controlled. It is low-cost because it requires no current or phase voltage sensors.

Patil, N.; Lawler, J.S.; McKeever, J.

2007-07-31T23:59:59.000Z

298

Experimental Design for a Macrofoam Swab Study Relating the Recovery Efficiency and False Negative Rate to Low Concentrations of Two Bacillus anthracis Surrogates on Four Surface Materials  

SciTech Connect (OSTI)

This report describes the experimental design for a laboratory study to quantify the recovery efficiencies and false negative rates of a validated, macrofoam swab sampling method for low concentrations of Bacillus anthracis Sterne (BAS) and Bacillus atrophaeus (BG) spores on four surface materials (stainless steel, glass, vinyl tile, plastic light cover panel). Two analytical methods (plating/counting and polymerase chain reaction) will be used. Only one previous study has investigated false negative as a function of affecting test factors. The surrogates BAS and BG have not been tested together in the same study previously. Hence, this study will provide for completing gaps in the available information on the performance of macrofoam swab sampling at low concentrations.

Piepel, Gregory F.; Hutchison, Janine R.

2014-04-16T23:59:59.000Z

299

Experimental Design for a Macrofoam-Swab Study Relating the Recovery Efficiency and False Negative Rate to Low Concentrations of Two Bacillus anthracis Surrogates on Four Surface Materials  

SciTech Connect (OSTI)

This report describes the experimental design for a laboratory study to quantify the recovery efficiencies and false negative rates of a validated, macrofoam-swab sampling method for low concentrations of Bacillus anthracis Sterne (BAS) and Bacillus atrophaeus (BG) spores on four surface materials (stainless steel, glass, vinyl tile, plastic light cover panel). Two analytical methods (culture and polymerase chain reaction) will be used. Only one previous study has investigated how the false negative rate depends on test factors. The surrogates BAS and BG have not been tested together in the same study previously. Hence, this study will provide for completing gaps in the available information on the performance of macrofoam-swab sampling at low concentrations.

Piepel, Gregory F.; Hutchison, Janine R.

2014-12-05T23:59:59.000Z

300

Magnetism in metal-organic capsules  

E-Print Network [OSTI]

Quantum Spin Chains in Magnetism: Molecules to Materials, J.Magnetism in metal-organic capsules Jerry L. Atwood,* a Euan

Atwood, Jerry L.

2010-01-01T23:59:59.000Z

Note: This page contains sample records for the topic "magnetism materials surface" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


301

Protein encapsulated magnetic carriers for micro/nanoscale drug delivery systems.  

SciTech Connect (OSTI)

Novel methods for drug delivery may be based on nanotechnology using non-invasive magnetic guidance of drug loaded magnetic carriers to the targeted site and thereafter released by external ultrasound energy. The key building block of this system is to successfully synthesize biodegradable, magnetic drug carriers. Magnetic carriers using poly(D,L-lactide-co-glycolide) (PLGA) or poly(lactic acid)-poly(ethylene glycol) (PLA-PEG) as matrix materials were loaded with bovine serum albumin (BSA) by a double-emulsion technique. BSA-loaded magnetic microspheres were characterized for size, morphology, surface charge, and magnetization. The BSA encapsulation efficiency was determined by recovering albumin from the microspheres using dimethyl sulfoxide and 0.05N NaOH/0.5% SDS then quantifying with the Micro-BCA protein assay. BSA release profiles were also determined by the Micro-BCA protein assay. The microspheres had drug encapsulation efficiencies up to 90% depending on synthesis parameters. Particles were spherical with a smooth or porous surface having a size range less than 5 {mu}m. The surface charge (expressed as zeta potential) was near neutral, optimal for prolonged intravascular survival. The magnetization of these BSA loaded magnetic carriers was 2 to 6 emu/g, depending on the specific magnetic materials used during synthesis.

Xie, Y.; Kaminski, M. D.; Mertz, C. J.; Finck, M. R.; Guy, S. G.; Chen, H.; Rosengart, A. J.; Chemical Engineering; Univ. of Chicago, Pritzker School of Medicine

2005-01-01T23:59:59.000Z

302

Spectro-polarimetric Imaging Reveals Helical Magnetic Fields in Solar Prominence Feet  

E-Print Network [OSTI]

Solar prominences are clouds of cool plasma levitating above the solar surface and insulated from the million-degree corona by magnetic fields. They form in regions of complex magnetic topology, characterized by non-potential fields, which can evolve abruptly, disintegrating the prominence and ejecting magnetized material into the heliosphere. However, their physics is not yet fully understood because mapping such complex magnetic configurations and their evolution is extremely challenging, and must often be guessed by proxy from photometric observations.Using state-of-the-art spectro-polarimetric data, we reconstruct the structure of the magnetic field in a prominence. We find that prominence feet harbor helical magnetic fields connecting the prominence to the solar surface below.

Gonzalez, M J Martinez; Ramos, A Asensio; Beck, C; Rodriguez, J de la Cruz; Diaz, A J

2015-01-01T23:59:59.000Z

303

Control of Surface Mounted Permanent Magnet Motors with Special Application to Fractional-Slot Motors with Concentrated Windings  

SciTech Connect (OSTI)

A 30 pole, 6 kW, and 6000 maximum revolutions per minute (rpm) prototype of the permanent magnet synchronous motor (PMSM) with fractional-slot concentrated windings (FSCW) has been designed, built, and tested at the University of Wisconsin at Madison (UWM). This machine has significantly more inductance than that of regular PMSMs. The prototype was delivered in April 2006 to the Oak Ridge National Laboratory (ORNL) for testing and development of a controller that will achieve maximum efficiency. In advance of the test/control development effort, ORNL has used the PMSM models developed over a number of previous studies to study how steady state performance of high inductance PMSM machines relates to control issues. This report documents the results of this research. The amount of inductance that enables the motor to achieve infinite constant power speed ratio (CPSR) is given by L{sub {infinity}} = E{sub b}/{Omega}{sub b}I{sub R}, where E{sub b} is the root-mean square (rms) magnitude of the line-to-neutral back-electromotive force (emf) at base speed, {Omega}{sub b} is the base speed in electrical radians per second, and I{sub R} is the rms current rating of the motor windings. The prototype machine that was delivered to ORNL has about 1.5 times as much inductance as a typical PMSM with distributed integral slot windings. The inventors of the FSCW method, who designed the prototype machine, remarked that they were 'too successful' in incorporating inductance into their machine and that steps would be taken to modify the design methodology to reduce the inductance to the optimum value. This study shows a significant advantage of having the higher inductance rather than the optimal value because it enables the motor to develop the required power at lower current thereby reducing motor and inverter losses and improving efficiency. The main problem found with high inductance machines driven by a conventional phase advance (CPA) method is that the motor current at high speed depends solely on machine parameters and is virtually independent of the load level and the direct current (dc) supply voltage. Thus, the motor current is virtually the same at no load as at full load resulting in poor efficiency at less than full load conditions. While an inductance higher than the value cited above is warranted, it still does not ensure that the motor current is proportional to load; consequently, the problem of low efficiency at high speed and partial load is not resolved but is only mitigated. A common definition of 'base speed' is the speed at which the voltage applied to the motor armature is equal to the magnitude of the back-emf. The results in this study indicate that the dc supply voltage should be adequate to drive rated current into the motor winding at the specified base speed. At a minimum this requires sufficient voltage to overcome not only the back-emf but also the voltage drop across the internal impedance of the machine. For a high inductance PMSM, the internal impedance at base speed can be considerable and substantial additional voltage is required to overcome the internal voltage drop. It is further shown that even more voltage than the minimum required for injecting rated current at base speed can be beneficial by allowing the required power to be developed at lower current, which reduces losses in the motor and inverter components. Further, it is shown that the current is minimized at a unique speed; consequently, there may be room for optimization if the drive spends a substantial amount of its operating life at a certain speed (for example 60 mph). In this study, fundamental frequency phasor models are developed for a synchronous PMSM and the control systems that drive them is CPA. The models were compared with detailed simulations to show their validity. The result was used to design a traction drive control system with optimized efficiency to drive the fractional-slot motor with concentrated windings. The goal is to meet or exceed the FreedomCAR inverter cost and performance targets.

McKeever, John W [ORNL; Patil, Niranjan [University of Tennessee, Knoxville (UTK); Lawler, Jack [ORNL

2007-07-01T23:59:59.000Z

304

Materials research at selected Japanese laboratories. Based on a 1992 visit: Overview, summary of highlights, notes on laboratories and topics  

SciTech Connect (OSTI)

I visited Japan from June 29 to August 1, 1992. The purpose of this visit was to assess the status of materials science research at selected governmental, university and industrial laboratories and to established acquaintances with Japanese researchers. The areas of research covered by these visits included ceramics, oxide superconductors, intermetallics alloys, superhard materials and diamond films, high-temperature materials and properties, mechanical properties, fracture, creep, fatigue, defects, materials for nuclear reactor applications and irradiation effects, high pressure synthesis, self-propagating high temperature synthesis, microanalysis, magnetic properties and magnetic facilities, and surface science.

Not Available

1994-02-01T23:59:59.000Z

305

Atomic multipole relaxation rates near surfaces  

E-Print Network [OSTI]

The spontaneous relaxation rates for an atom in free space and close to an absorbing surface are calculated to various orders of the electromagnetic multipole expansion. The spontaneous decay rates for dipole, quadrupole and octupole transitions are calculated in terms of their respective primitive electric multipole moments and the magnetic relaxation rate is calculated for the dipole and quadrupole transitions in terms of their respective primitive magnetic multipole moments. The theory of electromagnetic field quantization in magnetoelectric materials is used to derive general expressions for the decay rates in terms of the dyadic Green function. We focus on the decay rates in free space and near an infinite half space. For the decay of atoms near to an absorbing dielectric surface we find a hierarchy of scaling laws depending on the atom-surface distance z.

J. A. Crosse; Stefan Scheel

2010-08-13T23:59:59.000Z

306

Hardfacing material  

DOE Patents [OSTI]

A method of producing a hard metallic material by forming a mixture containing at least 55% iron and at least one of boron, carbon, silicon and phosphorus. The mixture is formed into an alloy and cooled to form a metallic material having a hardness of greater than about 9.2 GPa. The invention includes a method of forming a wire by combining a metal strip and a powder. The metal strip and the powder are rolled to form a wire containing at least 55% iron and from two to seven additional elements including at least one of C, Si and B. The invention also includes a method of forming a hardened surface on a substrate by processing a solid mass to form a powder, applying the powder to a surface to form a layer containing metallic glass, and converting the glass to a crystalline material having a nanocrystalline grain size.

Branagan, Daniel J. (Iona, ID)

2012-01-17T23:59:59.000Z

307

Vibrational Damping of Composite Materials  

E-Print Network [OSTI]

the damping material and epoxy resin. The surface of theinfiltration of the epoxy resin into the damping materialthe damping material and resin (epoxy) is occurring and is

Biggerstaff, Janet M.

2006-01-01T23:59:59.000Z

308

Measurement of Thermal Diffusivity and Conductivity in Advanced Nanostructured Materials  

E-Print Network [OSTI]

in Magnetic Materials . . . . . . . . . . . . . . . viimportants of understanding materials properties typicallyY.S. Ju, Annual Review of Materials Science, 29, 261 (1999).

Teweldebrhan, Desalegne Bekuretsion

2012-01-01T23:59:59.000Z

309

Thermal structure and cooling of superfluid neutron stars with accreted magnetized envelopes  

E-Print Network [OSTI]

We study the thermal structure of neutron stars with magnetized envelopes composed of accreted material, using updated thermal conductivities of plasmas in quantizing magnetic fields, as well as equation of state and radiative opacities for partially ionized hydrogen in strong magnetic fields. The relation between the internal and local surface temperatures is calculated and fitted by an analytic function of the internal temperature, magnetic field strength, angle between the field lines and the normal to the surface, surface gravity, and the mass of the accreted material. The luminosity of a neutron star with a dipole magnetic field is calculated for various values of the accreted mass, internal temperature, and magnetic field strength. Using these results, we simulate cooling of superfluid neutron stars with magnetized accreted envelopes. We consider slow and fast cooling regimes, paying special attention to very slow cooling of low-mass superfluid neutron stars. In the latter case, the cooling is strongly affected by the combined effect of magnetized accreted envelopes and neutron superfluidity in the stellar crust. Our results are important for interpretation of observations of isolated neutron stars hottest for their age, such as RX J0822-43 and PSR B1055-52.

A. Y. Potekhin; D. G. Yakovlev; G. Chabrier; O. Y. Gnedin

2003-09-17T23:59:59.000Z

310

Magnetic domain walls driven by interfacial phenomena  

E-Print Network [OSTI]

A domain wall in a ferromagnetic material is a boundary between differently magnetized regions, and its motion provides a convenient scheme to control the magnetization state of the material. Domain walls can be confined ...

Emori, Satoru

2014-01-01T23:59:59.000Z

311

CRITICAL MATERIALS INSTITUTE PROJECTS  

Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

INL Recovery of Critical Materials from Consumer Devices 3 3-2 3.2.6 McCall, Scott LLNL Additive Manufacturing of Permanent Magnets 2 2-1 2.1.2 McGuire, Michael ORNL...

312

CRITICAL MATERIALS INSTITUTE PROJECTS  

Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

INL National Technology Roadmap for Critical Materials 4 4-3 4.3.3 McCall, Scott LLNL Additive Manufacturing of Permanent Magnets 2 2-1 2.1.2 Payne, Steve LLNL New Efficient...

313

The interactive effects of pH, surface tension, and solution density for flotation systems for separation of equivalent-density materials: separation of ABS from HIPS  

SciTech Connect (OSTI)

This paper presents the results of research being conducted at Argonne National Laboratory, to develop a cost-effective and environmentally acceptable process for the separation of high-value plastics from discarded household appliances. The process under development has separated high-purity (greater than 99.5%) acrylonitrile-butadiene-styrene (ABS) and high-impact polystyrene (HIPS) from commingled plastics generated by appliance-shredding and metal recovery operations. Plastics of similar densities, such as ABS and HIPS are further separated by using a chemical solution. By controlling the surface tension, the density and the temperature of the chemical solution, we are able to selectively float/separate plastics that have equivalent densities. In laboratory-scale tests, this technique has proven highly effective in recovering high-purity plastics materials from discarded household appliances and other obsolete durable goods. A pilot plant is under construction to demonstrate and assess the technical and economic performance of this process. In this paper, we examine the technical and economic issues that affect the recovery and separation of plastics and provide an update on Argonne`s plastics separation research and development activities.

Karvelas, D.E.; Jody, B.J.; Pomykala, J.A.; Daniels, E.J.

1996-07-01T23:59:59.000Z

314

Large Magnetization at Carbon Surfaces  

Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE:1 First Use of Energy for All Purposes (Fuel and Nonfuel),Feet) Year Jan Feb Mar Apr May JunDatastreamsmmcrcalgovInstrumentsruc DocumentationP-SeriesFlickrinformationPostdocs space CombinedValues shown forShadeandLarge

315

Large Magnetization at Carbon Surfaces  

Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE:1 First Use of Energy for All Purposes (Fuel and Nonfuel),Feet) Year Jan Feb Mar Apr May JunDatastreamsmmcrcalgovInstrumentsruc DocumentationP-SeriesFlickrinformationPostdocs space CombinedValues shown forShadeandLargeLarge

316

Permanent Magnet Ecr Plasma Source With Magnetic Field Optimization  

DOE Patents [OSTI]

In a plasma-producing device, an optimized magnet field for electron cyclotron resonance plasma generation is provided by a shaped pole piece. The shaped pole piece adjusts spacing between the magnet and the resonance zone, creates a convex or concave resonance zone, and decreases stray fields between the resonance zone and the workpiece. For a cylindrical permanent magnet, the pole piece includes a disk adjacent the magnet together with an annular cylindrical sidewall structure axially aligned with the magnet and extending from the base around the permanent magnet. The pole piece directs magnetic field lines into the resonance zone, moving the resonance zone further from the face of the magnet. Additional permanent magnets or magnet arrays may be utilized to control field contours on a local scale. Rather than a permeable material, the sidewall structure may be composed of an annular cylindrical magnetic material having a polarity opposite that of the permanent magnet, creating convex regions in the resonance zone. An annular disk-shaped recurve section at the end of the sidewall structure forms magnetic mirrors keeping the plasma off the pole piece. A recurve section composed of magnetic material having a radial polarity forms convex regions and/or magnetic mirrors within the resonance zone.

Doughty, Frank C. (Plano, TX); Spencer, John E. (Plano, TX)

2000-12-19T23:59:59.000Z

317

Design of a scanning Josephson junction microscope for submicron-resolution magnetic imaging  

SciTech Connect (OSTI)

We describe a magnetic field scanning instrument designed to extend the spatial resolution of scanning superconducting quantum interference device microscopy into the submicron regime. This instrument, the scanning Josephson junction microscope, scans a single Josephson junction across the surface of a sample, detecting the local magnetic field by the modulation of the junction critical current. By using a submicron junction and a scanning tunneling microscope feedback system to maintain close proximity to the surface, magnetic field sensitivity of 10 {mu}G with a spatial resolution of 0.3 {mu}m should be attainable, opening up new opportunities for imaging vortex configurations and core structure in superconductors and magnetic domains in magnetic materials. {copyright} {ital 1999 American Institute of Physics.}

Plourde, B.L.; Van Harlingen, D.J. [Department of Physics, Science and Technology Center for Superconductivity, and Materials Research Laboratory, University of Illinois at Urbana-Champaign, Urbana, Illinois 61801 (United States)] [Department of Physics, Science and Technology Center for Superconductivity, and Materials Research Laboratory, University of Illinois at Urbana-Champaign, Urbana, Illinois 61801 (United States)

1999-11-01T23:59:59.000Z

318

The DOE Center of Excellence for the Synthesis and Processing of Advanced Materials: Research briefs  

SciTech Connect (OSTI)

This publication is designed to inform present and potential customers and partners of the DOE Center of Excellence for the Synthesis and Processing of Advanced Materials about significant advances resulting from Center-coordinated research. The format is an easy-to-read, not highly technical, concise presentation of the accomplishments. Selected accomplishments from each of the Center`s seven initial focused projects are presented. The seven projects are: (1) conventional and superplastic forming; (2) materials joining; (3) nanoscale materials for energy applications; (4) microstructural engineering with polymers; (5) tailored microstructures in hard magnets; (6) processing for surface hardness; and (7) mechanically reliable surface oxides for high-temperature corrosion resistance.

NONE

1996-01-01T23:59:59.000Z

319

Journal of Computer-Aided Materials Design, 8: 138, 2002. KLUWER/ESCOM  

E-Print Network [OSTI]

-organization in irradiated materials N.M. GHONIEMa , D. WALGRAEFb, and S.J. ZINKLEc a Mechanical and Aerospace Engineering as diverse as solidification [11], electro-chemical deposition [12], plastic deformation (e.g., [13, 14]), surface modifications [15], rapid laser heating [16], irradiation by energetic particles [17], magnetic

Ghoniem, Nasr M.

320

Magnetic Exchange Coupling and Single-Molecule Magnetism in Uranium Complexes  

E-Print Network [OSTI]

J. -P. ; Kahn, M. L. In Magnetism: Molecules to Materials V.R. Simple Models of Magnetism; Oxford University Press:for interpreting uranium magnetism and will be discussed in

Rinehart, Jeffrey Dennis

2010-01-01T23:59:59.000Z

Note: This page contains sample records for the topic "magnetism materials surface" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


321

E-Print Network 3.0 - ambient magnetic field Sample Search Results  

Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

; Materials Science 66 The Plasma Magnet for Deep Space Exploration Summary: and Andrews,1991) 12;How Plasma Magnet works Rotating Magnetic Field (RMF) rotates at RMF ce > RMF...

322

Porous Materials Porous Materials  

E-Print Network [OSTI]

1 Porous Materials x Porous Materials · Physical properties * Characteristic impedance p = p 0 e -jk xa- = vej[ ] p x - j ; Zc= p ve = c ka 0k = c 1-j #12;2 Porous Materials · Specific acoustic impedance Porous Materials · Finite thickness ­ blocked p e + -jk (x-d)a p e - jk (x-d)a d x #12

Berlin,Technische Universität

323

Ultrafast Magnetism Dynamics Measure Using Tabletop Ultrafast EUV Sources  

SciTech Connect (OSTI)

In our work to date, we made two significant advances. First we demonstrated element-selective demagnetization dynamics for the first time, with a record time resolution for x-ray probing of 55 fs. Second, in new work, we were able to probe the timescale of the exchange interaction in magnetic materials, also for the first time. Our measurements were made using the transverse magneto-optic Kerr effect (T-MOKE) geometry, since the reflectivity of a magnetic material changes with the direction of the magnetization vector of a surface. In our experiment, we periodically reversed the magnetization direction of a grating structure made of Permalloy (Ni80Fe20) using an external magnetic field. To achieve maximum contrast, we used HHG light spanning the M-shell (3p) absorption edges of Fe and Ni. Our characterization of the static magnetization of a Permalloy sample shows high magnetic asymmetry at photon energies just above and below the absorption edges at 55 eV and 65 eV, respectively. This result is in excellent agreement with measurements done on the same using a synchrotron source.

Silva, Thomas J. [NIST] [NIST; Murnane, Margaret [University of Colorado] [University of Colorado

2013-08-21T23:59:59.000Z

324

Method for improving performance of high temperature superconductors within a magnetic field  

DOE Patents [OSTI]

The present invention provides articles including a base substrate including a layer of an oriented cubic oxide material having a rock-salt-like structure layer thereon; and, a buffer layer upon the oriented cubic oxide material having a rock-salt-like structure layer, the buffer layer having an outwardly facing surface with a surface morphology including particulate outgrowths of from 10 nm to 500 run in size at the surface, such particulate outgrowths serving as flux pinning centers whereby the article maintains higher performance within magnetic fields than similar articles without the necessary density of such outgrowths.

Wang, Haiyan (Los Alamos, NM); Foltyn, Stephen R. (Los Alamos, NM); Maiorov, Boris A. (Los Alamos, NM); Civale, Leonardo (Los Alamos, NM)

2010-01-05T23:59:59.000Z

325

Photoemission Spectroscopy of Magnetic and Nonmagnetic Impurities on the Surface of the Bi[subscript 2]Se[subscript 3] Topological Insulator  

E-Print Network [OSTI]

Dirac-like surface states on surfaces of topological insulators have a chiral spin structure that suppresses backscattering and protects the coherence of these states in the presence of nonmagnetic scatterers. In contrast, ...

Valla, T.

326

Magnetic properties of mesoporous cobalt-silica-alumina ternary mixed oxides  

SciTech Connect (OSTI)

Mesoporous cobalt-silica-alumina mixed oxides with variable cobalt content have been synthesized through slow evaporation method by using Pluronic F127 non-ionic surfactant as template. N{sub 2} sorption analysis of the template-free mixed oxide samples revealed that these mesoporous materials have high BET surface areas together with large mesopores. Powder XRD, TEM, EDS, FT IR and EPR spectroscopic analysis have been employed to understand the nature of the mesophases, bonding and composition of the materials. Low temperature magnetic measurements of these mixed oxide materials show the presence of ferromagnetic correlation at elevated temperature though at low temperature paramagnetic to ferrimagnetic transition is observed. Highlights: Black-Right-Pointing-Pointer Mesoporous cobalt-silica-alumina ternary mixed oxides. Black-Right-Pointing-Pointer High surface area and mesoporosity in magnetic materials. Black-Right-Pointing-Pointer Ferromagnetic correlation at elevated temperature. Black-Right-Pointing-Pointer Low temperature paramagnetic to ferrimagnetic transition.

Pal, Nabanita [Department of Materials Science, Indian Association for the Cultivation of Science, Jadavpur, Kolkata 700 032 (India)] [Department of Materials Science, Indian Association for the Cultivation of Science, Jadavpur, Kolkata 700 032 (India); Seikh, Md. Motin [Department of Chemistry, Visva-Bharati University, Santiniketan, West Bengal (India)] [Department of Chemistry, Visva-Bharati University, Santiniketan, West Bengal (India); Bhaumik, Asim, E-mail: msab@iacs.res.in [Department of Materials Science, Indian Association for the Cultivation of Science, Jadavpur, Kolkata 700 032 (India)] [Department of Materials Science, Indian Association for the Cultivation of Science, Jadavpur, Kolkata 700 032 (India)

2013-02-15T23:59:59.000Z

327

Magnetic phase composition of strontium titanate implanted with iron ions  

SciTech Connect (OSTI)

Highlights: Black-Right-Pointing-Pointer The origin of RT-ferromagnetism in iron implanted strontium titanate. Black-Right-Pointing-Pointer Metallic iron nanoclusters form during implantation and define magnetic behaviour. Black-Right-Pointing-Pointer Paramagnetic at room temperature iron-substituted strontium titanate identified. -- Abstract: Thin magnetic films were synthesized by means of implantation of iron ions into single-crystalline (1 0 0) substrates of strontium titanate. Depth-selective conversion electron Moessbauer spectroscopy (DCEMS) indicates that origin of the samples magnetism is {alpha}-Fe nanoparticles. Iron-substituted strontium titanate was also identified but with paramagnetic behaviour at room temperature. Surface magneto-optical Kerr effect (SMOKE) confirms that the films reveal superparamagnetism (the low-fluence sample) or ferromagnetism (the high-fluence sample), and demonstrate absence of magnetic in-plane anisotropy. These findings highlight iron implanted strontium titanate as a promising candidate for composite multiferroic material and also for gas sensing applications.

Dulov, E.N., E-mail: evgeny.dulov@ksu.ru [Kazan Federal University, 420008 Kazan (Russian Federation); Ivoilov, N.G.; Strebkov, O.A. [Kazan Federal University, 420008 Kazan (Russian Federation)] [Kazan Federal University, 420008 Kazan (Russian Federation); Tagirov, L.R. [Kazan Federal University, 420008 Kazan (Russian Federation) [Kazan Federal University, 420008 Kazan (Russian Federation); Zavoisky Physico-Technical Institute, Kazan Scientific Center, Russian Academy of Sciences, 420029 Kazan (Russian Federation); Nuzhdin, V.I. [Zavoisky Physico-Technical Institute, Kazan Scientific Center, Russian Academy of Sciences, 420029 Kazan (Russian Federation)] [Zavoisky Physico-Technical Institute, Kazan Scientific Center, Russian Academy of Sciences, 420029 Kazan (Russian Federation); Khaibullin, R.I. [Kazan Federal University, 420008 Kazan (Russian Federation) [Kazan Federal University, 420008 Kazan (Russian Federation); Zavoisky Physico-Technical Institute, Kazan Scientific Center, Russian Academy of Sciences, 420029 Kazan (Russian Federation); Kazan, S. [Department of Physics, Gebze Institute of Technology, Gebze, 41400 Kocaeli (Turkey)] [Department of Physics, Gebze Institute of Technology, Gebze, 41400 Kocaeli (Turkey); Mikailzade, F.A. [Department of Physics, Gebze Institute of Technology, Gebze, 41400 Kocaeli (Turkey) [Department of Physics, Gebze Institute of Technology, Gebze, 41400 Kocaeli (Turkey); Institute of Physics, Azerbaijan National Academy of Sciences, H. Javid Av. 33, AZ 1143, Baku (Azerbaijan)

2011-12-15T23:59:59.000Z

328

Low-temperature magnetic refrigerator  

DOE Patents [OSTI]

The invention relates to magnetic refrigeration and more particularly to low temperature refrigeration between about 4 and about 20 K, with an apparatus and method utilizing a belt of magnetic material passed in and out of a magnetic field with heat exchangers within and outside the field operably disposed to accomplish refrigeration.

Barclay, J.A.

1983-05-26T23:59:59.000Z

329

Synthesis, crystal structure and magnetic property of a new 1D molecular material [1-(4'-chlorobenzyl)-4-aminopyridinium](+) bis(maleonitriledithiolato)nickel(-)  

SciTech Connect (OSTI)

A new ion-pair complex, [1-(4'-chlorobenzyl)-4-aminopyridinium](+)bis(maleonitrile-dithiolato) nickel(-),[ClbzPyNH{sub 2}][Ni(mnt){sub 2}] (1), has been prepared and characterized. X-ray single crystal structure conforms that the Ni(mnt){sub 2}{sup -} anions and [ClbzPyNH{sub 2}]{sup +} cations of 1 form completely segregated uniform stacking columns with the Ni...Ni distance 3.944A in the Ni(mnt){sub 2}{sup -} stacking column. The temperature dependence of the magnetic susceptibility reveals that 1 undergoes a magnetic transition, and exhibits ferromagnetic interaction in the high-temperature phase and spin gap system in the low-temperature phase.

Ni Chunlin [State Key Laboratory of Coordination Chemistry, Department of Chemistry, Coordination Chemistry Institute, Nanjing University, Hankou Road, Number 22, Nanjing city, Jiangsu province 210093 (China); Dang Dongbin [State Key Laboratory of Coordination Chemistry, Department of Chemistry, Coordination Chemistry Institute, Nanjing University, Hankou Road, Number 22, Nanjing city, Jiangsu province 210093 (China); Li Yizhi [State Key Laboratory of Coordination Chemistry, Department of Chemistry, Coordination Chemistry Institute, Nanjing University, Hankou Road, Number 22, Nanjing city, Jiangsu province 210093 (China); Gao Song [State Key Laboratory of Rare Earth Materials Chemistry and Applications, Peking University, 100 871 Beijing (China); Ni Zhaoping [State Key Laboratory of Coordination Chemistry, Department of Chemistry, Coordination Chemistry Institute, Nanjing University, Hankou Road, Number 22, Nanjing city, Jiangsu province 210093 (China); Tian Zhengfang [State Key Laboratory of Coordination Chemistry, Department of Chemistry, Coordination Chemistry Institute, Nanjing University, Hankou Road, Number 22, Nanjing city, Jiangsu province 210093 (China); Meng Qingjin [State Key Laboratory of Coordination Chemistry, Department of Chemistry, Coordination Chemistry Institute, Nanjing University, Hankou Road, Number 22, Nanjing city, Jiangsu province 210093 (China)]. E-mail: njuchem1024@163.com

2005-01-15T23:59:59.000Z

330

The surface-state of the topological insulator Bi2Se3 revealed by cyclotron resonance  

SciTech Connect (OSTI)

Transport measurements of topological insulators are dominated by the conductivity of the bulk, leading to substantial difficulties in resolving the properties of the surface. To this end, we use high magnetic field, rf- and microwave-spectroscopy to selectively couple to the surface conductivity of Bi2Se3 at high frequency. In the frequency range of a few GHz we observe a crossover from quantum oscillations indicative of a small 3D Fermi surface, to cyclotron resonance indicative of a 2D surface state. By probing the conductivity at reduced skin depths, we have observed a 2D cyclotron resonance from a material whose bulk Fermi-surface is 3D. The frequency-magnetic field scaling of this resonance is inconsistent with the bulk effective mass, but more consistent with the dispersion and band filling of a Dirac-like surface state as observed by ARPES, with substantial manybody renormalization.

Mcdonald, Ross D [Los Alamos National Laboratory; Ayala - Valenzuela, Oscar E [Los Alamos National Laboratory; Altarawneh, Moaz M [Los Alamos National Laboratory; Analytis, James G [STANFORD UNIV/SLAC; Chu, J. H. [STANFORD UNIV/SLAC; Fisher, R. [STANFORD UNIV/SLAC

2011-01-14T23:59:59.000Z

331

Optimal Magnetic Shield Design with Second–Order Cone ...  

E-Print Network [OSTI]

motors. Each car is equipped with several super-conducting magnet units .... [A3] Ferromagnetic material has saturated magnetic flux density Bs (unit: Tesla =.

2002-10-31T23:59:59.000Z

332

2011 Annual Report, National High Magnetic Field Laboratory  

Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

1 The Year in Review 06 Chapter 2 Research Highlights 10 Condensed Matter Science 12 Graphene, Kondoheavy fermion systems, magnetism & magnetic materials, molecular conductors,...

333

Journal of Intelligent Material Systems and Structures  

E-Print Network [OSTI]

by a magnetic field or vice versa. These materials are promising for wide engineering applica- tions, like composite can be induced by an applied magnetic potential. It means that a finite magnetoelectric of magnetoelectric coefficients. Pure magnetic and combined magnetic­mechanical loads are analyzed. The meshless

Pan, Ernie

334

Magnetic-field sensing coil embedded in ceramic for measuring ambient magnetic field  

DOE Patents [OSTI]

A magnetic pick-up coil for measuring magnetic field with high specific sensitivity, optionally with an electrostatic shield (24), having coupling elements (22) with high winding packing ratio, oriented in multiple directions, and embedded in ceramic material for structural support and electrical insulation. Elements of the coil are constructed from green ceramic sheets (200) and metallic ink deposited on surfaces and in via holes of the ceramic sheets. The ceramic sheets and the metallic ink are co-fired to create a monolithic hard ceramic body (20) with metallized traces embedded in, and placed on exterior surfaces of, the hard ceramic body. The compact and rugged coil can be used in a variety of environments, including hostile conditions involving ultra-high vacuum, high temperatures, nuclear and optical radiation, chemical reactions, and physically demanding surroundings, occurring either individually or in combinations.

Takahashi, Hironori

2004-02-10T23:59:59.000Z

335

Self-assembly of graphene oxide coated soft magnetic carbonyl iron particles and their magnetorheology  

SciTech Connect (OSTI)

The surface of carbonyl iron (CI) microspheres was modified with graphene oxide (GO) as a coating material using 4-aminobenzoic acid as the grafting agent. The morphology, elemental composition, and magnetic properties of the GO-coated CI (GO/CI) particles were examined by scanning electron microscopy, energy dispersive X-ray spectroscopy and vibrating sample magnetometry, respectively, confirming their composite formation. The magnetorheological (MR) performance of the GO/CI particle-based suspension was examined using a rotational rheometer connected to a magnetic field supply. The GO/CI particles suspension exhibited typical MR properties with increasing shear stress and viscosity depending on the applied magnetic field strength.

Zhang, W. L.; Choi, H. J., E-mail: hjchoi@inha.ac.kr [Department of Polymer Science and Engineering, Inha University, Incheon 402-751 (Korea, Republic of)

2014-05-07T23:59:59.000Z

336

Scalable Thick-Film Magnetics: Nano Structured Scalable Thick-Film Magnetics  

SciTech Connect (OSTI)

ADEPT Project: Magnetic components are typically the largest components in a power converter. To date, however, researchers haven't found an effective way to reduce their size without negatively impacting their performance. And, reducing the size of the converter's other components isn't usually an option because shrinking them can also diminish the effectiveness of the magnetic components. GE is developing smaller magnetic components for power converters that maintain high performance levels. The company is building smaller components with magnetic films. These films are created using the condensation of a vaporized form of the magnetic material. It's a purely physical process that involves no chemical reactions, so the film composition is uniform. This process makes it possible to create a millimeter-thick film deposition over a wide surface area fairly quickly, which would save on manufacturing costs. In fact, GE can produce 1-10 millimeter-thick films in hours. The magnetic components that GE is developing for this project could be used in a variety of applications, including solar inverters, electric vehicles, and lighting.

None

2011-01-01T23:59:59.000Z

337

Power-Invariant Magnetic System Modeling  

E-Print Network [OSTI]

properties and characteristics. Progress in magnetism was made after Oersted discovered in 1820 that a magnetic field could be generated with an electric current. Famous scientists, including Gauss, Maxwell and Faraday, tackled the phenomenon of magnetism... flows in the material. Meanwhile, in magnetic circuits, the reluctance is a measure of magnetic energy storage rather than being a measure of magnetic energy dissipation. 2. The Permeance-Capacitor Model In 1969, Dr. R.W. Buntenbach from...

Gonzalez Dominguez, Guadalupe Giselle

2012-10-19T23:59:59.000Z

338

Thickness dependence of magnetic anisotropy in thin Ni films electrodeposited onto the (011) and (001) surfaces of n-GaAs  

SciTech Connect (OSTI)

Brillouin light scattering from thermal spin waves has been exploited to investigate the thickness dependence of magnetic anisotropy of Ni films, with thickness in the range 7-35 nm, grown by electrodeposition onto either (011)- or (001)-GaAs substrates. In the former case, Ni films exhibit a well-defined in-plane uniaxial anisotropy induced by the symmetry of the substrate. In the case of the (001)-GaAs substrate, instead, the magnetic anisotropy results from a combination of both a fourfold and a twofold contribution. The physical mechanisms responsible for the observed anisotropy, as well as its dependence on film thickness, are discussed in detail.

Gubbiotti, G.; Carlotti, G.; Tacchi, S.; Liu, Y.-K.; Scheck, C.; Schad, R.; Zangari, G. [INFM CRS-SOFT, c/o Universita di Roma 'La Sapienza', I-00185, Rome (Italy); INFM UdR-Perugia, c/o Dipartimento di Fisica, Universita di Perugia, Via A. Pascoli, 06123 Perugia (Italy); INFM-National Center for nanoStructures and bioSystem at Surfaces (S3) Modena, and Dipartimento di Fisica, Universita di Perugia, Via A. Pascoli, 06123 Perugia (Italy); IINFM UdR-Perugia, Dipartimento di Fisica, Universita di Perugia, Via A. Pascoli, 06123 Perugia (Italy); MINT Center, University of Alabama, Tuscaloosa Alabama 35401 (United States); Department of Materials Science and Engineering and Center for Electrochemical Science and Engineering, University of Virginia, Charlottesville, Virginia 22904 (United States)

2005-05-15T23:59:59.000Z

339

Materials for light-induced water splitting: In situ controlled surface preparation of GaPN epilayers grown lattice-matched on Si(100)  

SciTech Connect (OSTI)

Energy storage is a key challenge in solar-driven renewable energy conversion. We promote a photochemical diode based on dilute nitride GaPN grown lattice-matched on Si(100), which could reach both high photovoltaic efficiencies and evolve hydrogen directly without external bias. Homoepitaxial GaP(100) surface preparation was shown to have a significant impact on the semiconductor-water interface formation. Here, we grow a thin, pseudomorphic GaP nucleation buffer on almost single-domain Si(100) prior to GaPN growth and compare the GaP{sub 0.98}N{sub 0.02}/Si(100) surface preparation to established P- and Ga-rich surfaces of GaP/Si(100). We apply reflection anisotropy spectroscopy to study the surface preparation of GaP{sub 0.98}N{sub 0.02} in situ in vapor phase epitaxy ambient and benchmark the signals to low energy electron diffraction, photoelectron spectroscopy, and x-ray diffraction. While the preparation of the Ga-rich surface is hardly influenced by the presence of the nitrogen precursor 1,1-dimethylhydrazine (UDMH), we find that stabilization with UDMH after growth hinders well-defined formation of the V-rich GaP{sub 0.98}N{sub 0.02}/Si(100) surface. Additional features in the reflection anisotropy spectra are suggested to be related to nitrogen incorporation in the GaP bulk.

Supplie, Oliver, E-mail: oliver.supplie@tu-ilmenau.de [Technische Universität Ilmenau, Institut für Physik, Gustav-Kirchhoff-Str. 5, 98684 Ilmenau (Germany); Helmholtz-Zentrum Berlin, Institute for Solar Fuels, Hahn-Meitner-Platz 1, 14109 Berlin (Germany); Humboldt-Universität zu Berlin, Institut für Physik, Newtonstr. 15, 12489 Berlin (Germany); May, Matthias M.; Stange, Helena [Helmholtz-Zentrum Berlin, Institute for Solar Fuels, Hahn-Meitner-Platz 1, 14109 Berlin (Germany); Humboldt-Universität zu Berlin, Institut für Physik, Newtonstr. 15, 12489 Berlin (Germany); Höhn, Christian [Helmholtz-Zentrum Berlin, Institute for Solar Fuels, Hahn-Meitner-Platz 1, 14109 Berlin (Germany); Lewerenz, Hans-Joachim [Helmholtz-Zentrum Berlin, Institute for Solar Fuels, Hahn-Meitner-Platz 1, 14109 Berlin (Germany); California Institute of Technology, Joint Center for Artificial Photosynthesis, 1200 East California Boulevard, Pasadena, California 91125 (United States); Hannappel, Thomas [Technische Universität Ilmenau, Institut für Physik, Gustav-Kirchhoff-Str. 5, 98684 Ilmenau (Germany); Helmholtz-Zentrum Berlin, Institute for Solar Fuels, Hahn-Meitner-Platz 1, 14109 Berlin (Germany)

2014-03-21T23:59:59.000Z

340

Casting materials  

DOE Patents [OSTI]

A foam material comprises a liquid polymer and a liquid isocyanate which is mixed to make a solution that is poured, injected or otherwise deposited into a corresponding mold. A reaction from the mixture of the liquid polymer and liquid isocyanate inside the mold forms a thermally collapsible foam structure having a shape that corresponds to the inside surface configuration of the mold and a skin that is continuous and unbroken. Once the reaction is complete, the foam pattern is removed from the mold and may be used as a pattern in any number of conventional casting processes.

Chaudhry, Anil R. (Xenia, OH); Dzugan, Robert (Cincinnati, OH); Harrington, Richard M. (Cincinnati, OH); Neece, Faurice D. (Lyndurst, OH); Singh, Nipendra P. (Pepper Pike, OH)

2011-06-14T23:59:59.000Z

Note: This page contains sample records for the topic "magnetism materials surface" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


341

Materials Science  

Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE:1 First Use of Energy for All Purposes (Fuel and Nonfuel),Feet) Year Jan Feb Mar Apr MayAtmospheric Optical Depth7-1D: VegetationEquipment Surfaces andMapping the Nanoscale LandscapeImports 5.90 4.86(NHMFL)X-RayMaterials

342

Microwave impregnation of porous materials with thermal energy storage materials  

DOE Patents [OSTI]

A method for impregnating a porous, non-metallic construction material with a solid phase-change material is described. The phase-change material in finely divided form is spread onto the surface of the porous material, after which the porous material is exposed to microwave energy for a time sufficient to melt the phase-change material. The melted material is spontaneously absorbed into the pores of the porous material. A sealing chemical may also be included with the phase-change material (or applied subsequent to the phase-change material) to seal the surface of the porous material. Fire retardant chemicals may also be included with the phase-change materials. The treated construction materials are better able to absorb thermal energy and exhibit increased heat storage capacity.

Benson, David K. (Golden, CO); Burrows, Richard W. (Conifer, CO)

1993-01-01T23:59:59.000Z

343

Microwave impregnation of porous materials with thermal energy storage materials  

DOE Patents [OSTI]

A method for impregnating a porous, non-metallic construction material with a solid phase-change material is described. The phase-change material in finely divided form is spread onto the surface of the porous material, after which the porous material is exposed to microwave energy for a time sufficient to melt the phase-change material. The melted material is spontaneously absorbed into the pores of the porous material. A sealing chemical may also be included with the phase-change material (or applied subsequent to the phase-change material) to seal the surface of the porous material. Fire retardant chemicals may also be included with the phase-change materials. The treated construction materials are better able to absorb thermal energy and exhibit increased heat storage capacity.

Benson, D.K.; Burrows, R.W.

1993-04-13T23:59:59.000Z

344

Chemistry and Materials Science progress report, first half FY 1992. Weapons-Supporting Research and Laboratory Directed Research and Development  

SciTech Connect (OSTI)

This report contains sections on: Fundamentals of the physics and processing of metals; interfaces, adhesion, and bonding; energetic materials; plutonium research; synchrotron radiation-based materials science; atomistic approach to the interaction of surfaces with the environment: actinide studies; properties of carbon fibers; buried layer formation using ion implantation; active coherent control of chemical reaction dynamics; inorganic and organic aerogels; synthesis and characterization of melamine-formaldehyde aerogels; structural transformation and precursor phenomena in advanced materials; magnetic ultrathin films, surfaces, and overlayers; ductile-phase toughening of refractory-metal intermetallics; particle-solid interactions; electronic structure evolution of metal clusters; and nanoscale lithography induced chemically or physically by modified scanned probe microscopy.

Not Available

1992-07-01T23:59:59.000Z

345

IEEE Transactions on Energy Conversion, Vol. 14, No. 4, December 1999 1043 OptimalCurrent Control Strategies for Surface-MountedPermanent-Magnet  

E-Print Network [OSTI]

. There has been considerable work in the area of choosing optimal current excitation of PMSM drives minimizing the rms stator Permanent-magnet synchronous machine (PMSM) drives current was set forth in [6 that In designing PMSM drives, two factors Of interest are would he difficult to implement in a real-time control

Chapman, Patrick

346

A garden mulch is any material spread on the soil surface to modify the environment where the plant is growing. The materials used can be natural or synthetic and can be used in any number of combinations  

E-Print Network [OSTI]

organic mulching materials include crushed corn cobs, peanut hulls, buckwheat hulls, bark and wood chips, wood shavings, seaweed and peat moss. All natural mulches should be applied after the crop has begun, as this increases the risk of disease. The soil should also be weed-free and moist. Pebbles, stone chips, gravel

New Hampshire, University of

347

Department of Advanced Materials Science  

E-Print Network [OSTI]

@k.u-tokyo.ac.jpe-mail 04-7136-3781T E L Environmental-friendly materials process, Metal smelting and re ning process of Advanced Materials Science masashi@issp.u-tokyo.ac.jpe-mail 04-7136-3225T E L Nuclear magnetic resonance New Materials Synthesis, Superconductivity, Quantum Spin Liquid,Topological Hall Effect takatama

Katsumoto, Shingo

348

Nanostructured materials for hydrogen storage  

DOE Patents [OSTI]

A system for hydrogen storage comprising a porous nano-structured material with hydrogen absorbed on the surfaces of the porous nano-structured material. The system of hydrogen storage comprises absorbing hydrogen on the surfaces of a porous nano-structured semiconductor material.

Williamson, Andrew J. (Pleasanton, CA); Reboredo, Fernando A. (Pleasanton, CA)

2007-12-04T23:59:59.000Z

349

Braze material for joining ceramic to metal and ceramic to ceramic surfaces and joined ceramic to metal and ceramic to ceramic article  

DOE Patents [OSTI]

An improved active metal braze filler material is provided in which the coefficient of thermal expansion of the braze filler is more closely matched with that of the ceramic and metal, or two ceramics, to provide ceramic to metal, or ceramic to ceramic, sealed joints and articles which can withstand both high temperatures and repeated thermal cycling without failing. The braze filler material comprises a mixture of a material, preferably in the form of a powder, selected from the group consisting of molybdenum, tungsten, silicon carbide and mixtures thereof, and an active metal filler material selected from the group consisting of alloys or mixtures of nickel and titanium, alloys or mixtures of nickel and zirconium, alloys or mixtures of nickel, titanium, and copper, alloys or mixtures of nickel, titanium, and zirconium, alloys or mixtures of niobium and nickel, alloys or mixtures of niobium and zirconium, alloys or mixtures of niobium and titanium, alloys or mixtures of niobium, titanium, and nickel, alloys or mixtures of niobium, zirconium, and nickel, and alloys or mixtures of niobium, titanium, zirconium, and nickel. The powder component is selected such that its coefficient of thermal expansion will effect the overall coefficient of thermal expansion of the braze material so that it more closely matches the coefficients of thermal expansion of the ceramic and metal parts to be joined. 3 figures.

Hunt, T.K.; Novak, R.F.

1991-05-07T23:59:59.000Z

350

Braze material for joining ceramic to metal and ceramic to ceramic surfaces and joined ceramic to metal and ceramic to ceramic article  

DOE Patents [OSTI]

An improved active metal braze filler material is provided in which the coefficient of thermal expansion of the braze filler is more closely matched with that of the ceramic and metal, or two ceramics, to provide ceramic to metal, or ceramic to ceramic, sealed joints and articles which can withstand both high temperatures and repeated thermal cycling without failing. The braze filler material comprises a mixture of a material, preferably in the form of a powder, selected from the group consisting of molybdenum, tungsten, silicon carbide and mixtures thereof, and an active metal filler material selected from the group consisting of alloys or mixtures of nickel and titanium, alloys or mixtures of nickel and zirconium, alloys or mixtures of nickel, titanium, and copper, alloys or mixtures of nickel, titanium, and zirconium, alloys or mixtures of niobium and nickel, alloys or mixtures of niobium and zirconium, alloys or mixtures of niobium and titanium, alloys or mixtures of niobium, titanium, and nickel, alloys or mixtures of niobium, zirconium, and nickel, and alloys or mixtures of niobium, titanium, zirconium, and nickel. The powder component is selected such that its coefficient of thermal expansion will effect the overall coefficient of thermal expansion of the braze material so that it more closely matches the coefficients of thermal expansion of the ceramic and metal parts to be joined.

Hunt, Thomas K. (Ann Arbor, MI); Novak, Robert F. (Farmington Hills, MI)

1991-01-01T23:59:59.000Z

351

Earth materials and earth dynamics  

SciTech Connect (OSTI)

In the project ''Earth Materials and Earth Dynamics'' we linked fundamental and exploratory, experimental, theoretical, and computational research programs to shed light on the current and past states of the dynamic Earth. Our objective was to combine different geological, geochemical, geophysical, and materials science analyses with numerical techniques to illuminate active processes in the Earth. These processes include fluid-rock interactions that form and modify the lithosphere, non-linear wave attenuations in rocks that drive plate tectonics and perturb the earth's surface, dynamic recrystallization of olivine that deforms the upper mantle, development of texture in high-pressure olivine polymorphs that create anisotropic velocity regions in the convecting upper mantle and transition zone, and the intense chemical reactions between the mantle and core. We measured physical properties such as texture and nonlinear elasticity, equation of states at simultaneous pressures and temperatures, magnetic spins and bonding, chemical permeability, and thermal-chemical feedback to better characterize earth materials. We artificially generated seismic waves, numerically modeled fluid flow and transport in rock systems and modified polycrystal plasticity theory to interpret measured physical properties and integrate them into our understanding of the Earth. This is the final report of a three-year, Laboratory-Directed Research and Development (LDRD) project at the Los Alamos National Laboratory (LANL).

Bennett, K; Shankland, T. [and others

2000-11-01T23:59:59.000Z

352

Magnetism in nanoparticle LaCoO3  

E-Print Network [OSTI]

Magnetism in nanoparticle LaCoO 3 A. M. Durand, 1 D. P.o ? 37 K. For T magnetism in bulk LCO is associatedto surfaces or interfaces. The magnetism of LaCoO 3 (LCO) is

Durand, A. M.

2013-01-01T23:59:59.000Z

353

Int. J. Computational Materials Science and Surface Engineering, Vol. 2, Nos. 3/4, 2009 225 Copyright 2009 Inderscience Enterprises Ltd.  

E-Print Network [OSTI]

, Silicon Carbide (SiC) has become an alternative material to replace Si for Microelectromechanical Systems; microelectromechanical systems; review; deposition; fabrication; devices; prospect. Reference to this paper should and the development of state-of-the-art SiC Microelectromechanical Systems (MEMS). She is currently a Research Council

354

HIGH-FIELD SUPERCONDUCTING ACCELERATOR MAGNETS  

E-Print Network [OSTI]

D. C. 'Niobium-Titanium Superconducting Material s ', in S.14, 1982 HIGH-FIELD SUPERCONDUCTING ACCELERATOR MAGNETS C.SUMAG-68 HIGH-FIELD SUPERCONDUCTING ACCELERATOR MAGNETS* C.

Taylor, C.

2011-01-01T23:59:59.000Z

355

Fast superconducting magnetic field switch  

DOE Patents [OSTI]

The superconducting magnetic switch or fast kicker magnet is employed with electron stream or a bunch of electrons to rapidly change the direction of flow of the electron stream or bunch of electrons. The apparatus employs a beam tube which is coated with a film of superconducting material. The tube is cooled to a temperature below the superconducting transition temperature and is subjected to a constant magnetic field which is produced by an external dc magnet. The magnetic field produced by the dc magnet is less than the critical field for the superconducting material, thus, creating a Meissner Effect condition. A controllable fast electromagnet is used to provide a magnetic field which supplements that of the dc magnet so that when the fast magnet is energized the combined magnetic field is now greater that the critical field and the superconducting material returns to its normal state allowing the magnetic field to penetrate the tube. This produces an internal field which effects the direction of motion and of the electron stream or electron bunch. The switch can also operate as a switching mechanism for charged particles.

Goren, Yehuda (Mountain View, CA); Mahale, Narayan K. (The Woodlands, TX)

1996-01-01T23:59:59.000Z

356

Platinum dendritic nanoparticles with magnetic behavior  

SciTech Connect (OSTI)

Magnetic nanoparticles have attracted increasing attention for biomedical applications in magnetic resonance imaging, high frequency magnetic field hyperthermia therapies, and magnetic-field-gradient-targeted drug delivery. In this study, three-dimensional (3D) platinum nanostructures with large surface area that features magnetic behavior have been demonstrated. The well-developed 3D nanodendrites consist of plentiful interconnected nano-arms ?4?nm in size. The magnetic behavior of the 3D dendritic Pt nanoparticles is contributed by the localization of surface electrons due to strongly bonded oxygen/Pluronic F127 and the local magnetic moment induced by oxygen vacancies on the neighboring Pt and O atoms. The magnetization of the nanoparticles exhibits a mixed paramagnetic and ferromagnetic state, originating from the core and surface, respectively. The 3D nanodendrite structure is suitable for surface modification and high amounts of drug loading if the transition temperature was enhanced to room temperature properly.

Li, Wenxian, E-mail: wl240@uowmail.edu.au [Institute for Superconducting and Electronic Materials, University of Wollongong, NSW 2522 (Australia); Solar Energy Technologies, School of Computing, Engineering, and Mathematics, University of Western Sydney, Penrith NSW 2751 (Australia); Sun, Ziqi; Nevirkovets, Ivan P.; Dou, Shi-Xue [Institute for Superconducting and Electronic Materials, University of Wollongong, NSW 2522 (Australia); Tian, Dongliang [Key Laboratory of Bio-Inspired Smart Interfacial Science and Technology of the Ministry of Education, School of Chemistry and the Environment, Beihang University, Beijing 100191 (China)

2014-07-21T23:59:59.000Z

357

Joining of dissimilar materials  

DOE Patents [OSTI]

A method of joining dissimilar materials having different ductility, involves two principal steps: Decoration of the more ductile material's surface with particles of a less ductile material to produce a composite; and, sinter-bonding the composite produced to a joining member of a less ductile material. The joining method is suitable for joining dissimilar materials that are chemically inert towards each other (e.g., metal and ceramic), while resulting in a strong bond with a sharp interface between the two materials. The joining materials may differ greatly in form or particle size. The method is applicable to various types of materials including ceramic, metal, glass, glass-ceramic, polymer, cermet, semiconductor, etc., and the materials can be in various geometrical forms, such as powders, fibers, or bulk bodies (foil, wire, plate, etc.). Composites and devices with a decorated/sintered interface are also provided.

Tucker, Michael C; Lau, Grace Y; Jacobson, Craig P

2012-10-16T23:59:59.000Z

358

Atom chip microscopy: A novel probe for strongly correlated materials  

SciTech Connect (OSTI)

Improved measurements of strongly correlated systems will enable the predicative design of the next generation of supermaterials. In this program, we are harnessing recent advances in the quantum manipulation of ultracold atomic gases to expand our ability to probe these technologically important materials in heretofore unexplored regions of temperature, resolution, and sensitivity parameter space. We are working to demonstrate the use of atom chips to enable single-shot, large area detection of magnetic flux at the 10^-7 flux quantum level and below. By harnessing the extreme sensitivity of atomic clocks and Bose-Einstein condensates (BECs) to external perturbations, the cryogenic atom chip technology developed here will provide a magnetic flux detection capability that surpasses other techniques---such as scanning SQUIDs---by a factor of 10--1000. We are testing the utility of this technique by using rubidium BECs to image the magnetic fields emanating from charge transport and magnetic domain percolation in strongly correlated materials as they undergo temperature-tuned metal--to--insulator phase transitions. Cryogenic atom chip microscopy introduces three very important features to the toolbox of high-resolution, strongly correlated material microscopy: simultaneous detection of magnetic and electric fields (down to the sub-single electron charge level); no invasive large magnetic fields or gradients; simultaneous micro- and macroscopic spatial resolution; freedom from 1/f flicker noise at low frequencies; and, perhaps most importantly, the complete decoupling of probe and sample temperatures. The first of these features will play an important role in studying the interplay between magnetic and electric domain structure. The last two are crucial for low frequency magnetic noise detection in, e.g., the cuprate pseudogap region and for precision measurements of transport in the high temperature, technologically relevant regime inaccessible to other techniques based on superconducting scanning probes. In periods 1--3 of this grant, which we now close at the University of Illinois at Urbana-Champaign and restart at Stanford University where our new lab is being built, we have demonstrated the ability to rapidly create Rb BECs and trap them within microns of a surface ina cryostat. Period 4 of this grant, to be performed at Stanford, will demonstrate the feasibility of using atom chips with a BEC to image transport features on a cryogenically cooled surface. Successful demonstration, in future funding cycles, will lead directly to the use of system for studies of transport in exotic and technologically relevant materials such as cuprate superconductors and topological insulators.

Lev, Benjamin L

2011-11-03T23:59:59.000Z

359

Large Superconducting Magnet Systems  

E-Print Network [OSTI]

The increase of energy in accelerators over the past decades has led to the design of superconducting magnets for both accelerators and the associated detectors. The use of Nb?Ti superconducting materials allows an increase in the dipole field by up to 10 T compared with the maximum field of 2 T in a conventional magnet. The field bending of the particles in the detectors and generated by the magnets can also be increased. New materials, such as Nb3Sn and high temperature superconductor (HTS) conductors, can open the way to higher fields, in the range 13–20 T. The latest generations of fusion machines producing hot plasma also use large superconducting magnet systems.

Védrine, P

2014-01-01T23:59:59.000Z

360

Acta Physicae Superficierum Vol VII 2004 EXPLORING ARTIFICIAL MAGNETISM  

E-Print Network [OSTI]

Acta Physicae Superficierum · Vol VII · 2004 EXPLORING ARTIFICIAL MAGNETISM FROM THIN FILMS of artificially structured, new magnetic materials play a fundamental role in modern science and technology. From thin films to patterned magnetic nano-structures, these magnetic materials and systems can be utilized

Rau, Carl

Note: This page contains sample records for the topic "magnetism materials surface" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


361

A New Class of Switched Reluctance Motors without Permanent Magnets  

Broader source: Energy.gov (indexed) [DOE]

switched reluctance motor benefits: - Low material and fabrication cost - No permanent magnet material * Back-emf and demagnetization is not an issue * Permits operation...

362

Soiling of building envelope surfaces and its effect on solar reflectance - Part II: Development of an accelerate aging method for roofing materials  

SciTech Connect (OSTI)

Highly reflective roofs can decrease the energy required for building air conditioning, help mitigate the urban heat island effect, and slow global warming. However, these benefits are diminished by soiling and weathering processes that reduce the solar reflectance of most roofing materials. Soiling results from the deposition of atmospheric particulate matter and the growth of microorganisms, each of which absorb sunlight. Weathering of materials occurs with exposure to water, sunlight, and high temperatures. This study developed an accelerated aging method that incorporates features of soiling and weathering. The method sprays a calibrated aqueous soiling mixture of dust minerals, black carbon, humic acid, and salts onto preconditioned coupons of roofing materials, then subjects the soiled coupons to cycles of ultraviolet radiation, heat and water in a commercial weatherometer. Three soiling mixtures were optimized to reproduce the site-specific solar spectral reflectance features of roofing products exposed for 3 years in a hot and humid climate (Miami, Florida); a hot and dry climate (Phoenix, Arizona); and a polluted atmosphere in a temperate climate (Cleveland, Ohio). A fourth mixture was designed to reproduce the three-site average values of solar reflectance and thermal emittance attained after 3 years of natural exposure, which the Cool Roof Rating Council (CRRC) uses to rate roofing products sold in the US. This accelerated aging method was applied to 25 products?single ply membranes, factory and field applied coatings, tiles, modified bitumen cap sheets, and asphalt shingles?and reproduced in 3 days the CRRC's 3-year aged values of solar reflectance. This accelerated aging method can be used to speed the evaluation and rating of new cool roofing materials.

Sleiman, Mohamad; Kirchstetter, Thomas W.; Berdahl, Paul; Gilbert, Haley; Quelen, Sarah; Marlot, Lea; Preble, Chelsea; Chen, Sharon; Montalbano, Amadine; Rosseler, Olivier; Akbari, Hashem; Levinson, Ronnen; Destaillats, Hugo

2013-11-18T23:59:59.000Z

363

Electric-Field Control of Magnetism Intrinsic magnetoelectric coupling describes the microscopic interaction between magnetic and  

E-Print Network [OSTI]

Electric-Field Control of Magnetism Intrinsic magnetoelectric coupling describes the microscopic interaction between magnetic and electric polarization in a single-phase material. The control of the magnetic state of a material with an electric field is an enticing prospect for device engineering. MRSEC

Maroncelli, Mark

364

Moment free toroidal magnet  

DOE Patents [OSTI]

A toroidal magnet for confining a high magnetic field for use in fusion reactor research and nuclear particle detection. The magnet includes a series of conductor elements arranged about and fixed at its small major radius portion to the outer surface of a central cylindrical support each conductor element having a geometry such as to maintain the conductor elements in pure tension when a high current flows therein, and a support assembly which redistributes all or part of the tension which would otherwise arise in the small major radius portion of each coil element to the large major radius portion thereof.

Bonanos, Peter (East Brunswick, NJ)

1983-01-01T23:59:59.000Z

365

Nanostructured composite reinforced material  

DOE Patents [OSTI]

A family of materials wherein nanostructures and/or nanotubes are incorporated into a multi-component material arrangement, such as a metallic or ceramic alloy or composite/aggregate, producing a new material or metallic/ceramic alloy. The new material has significantly increased strength, up to several thousands of times normal and perhaps substantially more, as well as significantly decreased weight. The new materials may be manufactured into a component where the nanostructure or nanostructure reinforcement is incorporated into the bulk and/or matrix material, or as a coating where the nanostructure or nanostructure reinforcement is incorporated into the coating or surface of a "normal" substrate material. The nanostructures are incorporated into the material structure either randomly or aligned, within grains, or along or across grain boundaries.

Seals, Roland D. (Oak Ridge, TN); Ripley, Edward B. (Knoxville, TN); Ludtka, Gerard M. (Oak Ridge, TN)

2012-07-31T23:59:59.000Z

366

Ubiquitous Solar Eruptions Driven by Magnetized Vortex Tubes  

E-Print Network [OSTI]

The solar surface is covered by high-speed jets transporting mass and energy into the solar corona and feeding the solar wind. The most prominent of these jets have been known as spicules. However, the mechanism initiating these eruptions events is still unknown. Using realistic numerical simulations we find that small-scale eruptions are produced by ubiquitous magnetized vortex tubes generated by the Sun's turbulent convection in subsurface layers. The swirling vortex tubes (resembling tornadoes) penetrate into the solar atmosphere, capture and stretch background magnetic field, and push surrounding material up, generating quasiperiodic shocks. Our simulations reveal a complicated high-speed flow patterns, and thermodynamic and magnetic structure in the erupting vortex tubes. We found that the eruptions are initiated in the subsurface layers and are driven by the high-pressure gradients in the subphotosphere and photosphere, and by the Lorentz force in the higher atmosphere layers.

Kitiashvili, I N; Lele, S K; Mansour, N N; Wray, A A

2013-01-01T23:59:59.000Z

367

Method for obtaining large levitation pressure in superconducting magnetic bearings  

DOE Patents [OSTI]

A method and apparatus are disclosed for compressing magnetic flux to achieve high levitation pressures. Magnetic flux produced by a magnetic flux source travels through a gap between two high temperature superconducting material structures. The gap has a varying cross-sectional area to compress the magnetic flux, providing an increased magnetic field and correspondingly increased levitation force in the gap. 4 figs.

Hull, J.R.

1997-08-05T23:59:59.000Z

368

Critical Materials Hub  

Broader source: Energy.gov [DOE]

Critical materials, including some rare earth elements that possess unique magnetic, catalytic, and luminescent properties, are key resources needed to manufacture products for the clean energy economy. These materials are so critical to the technologies that enable wind turbines, solar panels, electric vehicles, and energy-efficient lighting that DOE's 2010 and 2011 Critical Materials Strategy reported that supply challenges for five rare earth metals—dysprosium, neodymium, terbium, europium, and yttrium—could affect clean energy technology deployment in the coming years.1, 2

369

WAFER TEST CAVITY -Linking Surface Microstructure to RF Performance: a ‘Short-­?Sample Test Facility’ for characterizing superconducting materials for SRF cavities.  

SciTech Connect (OSTI)

The Wafer Test cavity was designed to create a short sample test system to determine the properties of the superconducting materials and S?I?S hetero?structures. The project, funded by ARRA, was successful in accomplishing several goals to achieving a high gradient test system for SRF research and development. The project led to the design and construction of the two unique cavities that each severed unique purposes: the Wafer test Cavity and the Sapphire Test cavity. The Sapphire Cavity was constructed first to determine the properties of large single crystal sapphires in an SRF environment. The data obtained from the cavity greatly altered the design of the Wafer Cavity and provided the necessary information to ascertain the Wafer Test cavity’s performance.

Pogue, Nathaniel; Comeaux, Justin; McIntyre, Peter

2014-05-30T23:59:59.000Z

370

Magnetic Resonance Facility (Fact Sheet)  

SciTech Connect (OSTI)

This fact sheet provides information about Magnetic Resonance Facility capabilities and applications at NREL's National Bioenergy Center. Liquid and solid-state analysis capability for a variety of biomass, photovoltaic, and materials characterization applications across NREL. NREL scientists analyze solid and liquid samples on three nuclear magnetic resonance (NMR) spectrometers as well as an electron paramagnetic resonance (EPR) spectrometer.

Not Available

2012-03-01T23:59:59.000Z

371

Magnetic metallic multilayers  

SciTech Connect (OSTI)

Utilizing self-consistent Hartree-Fock calculations, several aspects of multilayers and interfaces are explored: enhancement and reduction of the local magnetic moments, magnetic coupling at the interfaces, magnetic arrangements within each film and among non-neighboring films, global symmetry of the systems, frustration, orientation of the various moments with respect to an outside applied field, and magnetic-field induced transitions. Magnetoresistance of ferromagnetic-normal-metal multilayers is found by solving the Boltzmann equation. Results explain the giant negative magnetoresistance encountered in these systems when an initial antiparallel arrangement is changed into a parallel configuration by an external magnetic field. The calculation depends on (1) geometric parameters (thicknesses of layers), (2) intrinsic metal parameters (number of conduction electrons, magnetization, and effective masses in layers), (3) bulk sample properties (conductivity relaxation times), (4) interface scattering properties (diffuse scattering versus potential scattering at the interfaces, and (5) outer surface scattering properties (specular versus diffuse surface scattering). It is found that a large negative magnetoresistance requires considerable asymmetry in interface scattering for the two spin orientations. Features of the interfaces that may produce an asymmetrical spin-dependent scattering are studied: varying interfacial geometric random roughness with no lateral coherence, correlated (quasi-periodic) roughness, and varying chemical composition of the interfaces. The interplay between these aspects of the interfaces may enhance or suppress the magnetoresistance, depending on whether it increases or decreases the asymmetry in the spin-dependent scattering of the conduction electrons.

Hood, R.Q.

1994-04-01T23:59:59.000Z

372

Superconducting magnetic coil  

DOE Patents [OSTI]

A superconducting magnetic coil includes a plurality of sections positioned axially along the longitudinal axis of the coil, each section being formed of an anisotropic high temperature superconductor material wound about a longitudinal axis of the coil and having an associated critical current value that is dependent on the orientation of the magnetic field of the coil. The cross section of the superconductor, or the type of superconductor material, at sections along the axial and radial axes of the coil are changed to provide an increased critical current at those regions where the magnetic field is oriented more perpendicularly to the conductor plane, to thereby increase the critical current at these regions and to maintain an overall higher critical current of the coil. 15 figs.

Aized, D.; Schwall, R.E.

1999-06-22T23:59:59.000Z

373

Superconducting magnetic coil  

DOE Patents [OSTI]

A superconducting magnetic coil includes a plurality of sections positioned axially along the longitudinal axis of the coil, each section being formed of an anisotropic high temperature superconductor material wound about a longitudinal axis of the coil and having an associated critical current value that is dependent on the orientation of the magnetic field of the coil. The cross section of the superconductor, or the type of superconductor material, at sections along the axial and radial axes of the coil are changed to provide an increased critical current at those regions where the magnetic field is oriented more perpendicularly to the conductor plane, to thereby increase the critical current at these regions and to maintain an overall higher critical current of the coil.

Aized, Dawood (Marlboro, MA); Schwall, Robert E. (Northborough, MA)

1999-06-22T23:59:59.000Z

374

Catalyst material and method of making  

DOE Patents [OSTI]

The material of the present invention is a mixture of catalytically active material and carrier materials, which may be catalytically active themselves. Hence, the material of the present invention provides a catalyst particle that has catalytically active material throughout its bulk volume as well as on its surface. The presence of the catalytically active material throughout the bulk volume is achieved by chemical combination of catalytically active materials with carrier materials prior to or simultaneously with crystallite formation.

Matson, Dean W. (Kennewick, WA); Fulton, John L. (Richland, WA); Linehan, John C. (Richland, WA); Bean, Roger M. (Richland, WA); Brewer, Thomas D. (Richland, WA); Werpy, Todd A. (Richland, WA); Darab, John G. (Richland, WA)

1997-01-01T23:59:59.000Z

375

Casimir effect for thin films from imperfect materials  

E-Print Network [OSTI]

We propose an approach for investigation of interaction of thin material films with quantum electrodynamic fields. Using main principles of quantum electrodynamics (locality, gauge invariance, renormalizability) we construct a single model for Casimir-like phenomena arising near the film boundary on distances much larger then Compton wavelength of the electron where fluctuations of Dirac fields are not essential. In this model the thin film is presented by a singular background field concentrated on a 2-dimensional surface. All properties of the film material are described by one dimensionless parameter. For two parallel plane films we calculate the photon propagator and the Casimir force, which appears to be dependent on film material and can be both attractive and repulsive. We consider also an interaction of plane film with point charge and straight line current. Here, besides usual results of classical electrodynamics the model predicts appearance of anomalous electric and magnetic fields.

V. N. Markov; Yu. M. Pis'mak

2006-06-04T23:59:59.000Z

376

Validation of plasma shape reconstruction by Cauchy condition surface method in KSTAR  

SciTech Connect (OSTI)

Cauchy Condition Surface (CCS) method is a numerical approach to reconstruct the plasma boundary and calculate the quantities related to plasma shape using the magnetic diagnostics in real time. It has been applied to the KSTAR plasma in order to establish the plasma shape reconstruction with the high elongation of plasma shape and the large effect of eddy currents flowing in the tokamak structures for the first time. For applying the CCS calculation to the KSTAR plasma, the effects by the eddy currents and the ferromagnetic materials on the plasma shape reconstruction are studied. The CCS calculation includes the effect of eddy currents and excludes the magnetic diagnostics, which is expected to be influenced largely by ferromagnetic materials. Calculations have been performed to validate the plasma shape reconstruction in 2012 KSTAR experimental campaign. Comparison between the CCS calculation and non-magnetic measurements revealed that the CCS calculation can reconstruct the accurate plasma shape even with a small I{sub P}.

Miyata, Y.; Suzuki, T.; Ide, S. [Japan Atomic Energy Agency, Naka, Ibaraki 311-0193 (Japan)] [Japan Atomic Energy Agency, Naka, Ibaraki 311-0193 (Japan); Hahn, S. H.; Chung, J.; Bak, J. G.; Ko, W. H. [National Fusion Research Institute, Daejeon 305-333 (Korea, Republic of)] [National Fusion Research Institute, Daejeon 305-333 (Korea, Republic of)

2014-03-15T23:59:59.000Z

377

Combinatorial synthesis of ceramic materials  

DOE Patents [OSTI]

A combinatorial library includes a gelcast substrate defining a plurality of cavities in at least one surface thereof; and a plurality of gelcast test materials in the cavities, at least two of the test materials differing from the substrate in at least one compositional characteristic, the two test materials differing from each other in at least one compositional characteristic.

Lauf, Robert J.; Walls, Claudia A.; Boatner, Lynn A.

2006-11-14T23:59:59.000Z

378

Combinatorial synthesis of ceramic materials  

DOE Patents [OSTI]

A combinatorial library includes a gelcast substrate defining a plurality of cavities in at least one surface thereof; and a plurality of gelcast test materials in the cavities, at least two of the test materials differing from the substrate in at least one compositional characteristic, the two test materials differing from each other in at least one compositional characteristic.

Lauf, Robert J. (Oak Ridge, TN) [Oak Ridge, TN; Walls, Claudia A. (Oak Ridge, TN) [Oak Ridge, TN; Boatner, Lynn A. (Oak Ridge, TN) [Oak Ridge, TN

2010-02-23T23:59:59.000Z

379

Velocity damper for electromagnetically levitated materials  

DOE Patents [OSTI]

A system for damping oscillatory and spinning motions induced in an electromagnetically levitated material is disclosed. Two opposed field magnets are located orthogonally to the existing levitation coils for providing a DC quadrupole field (cusp field) around the material. The material used for generating the DC quadrupole field must be nonconducting to avoid eddy-current heating and of low magnetic permeability to avoid distorting the induction fields providing the levitation. 1 fig.

Fox, R.J.

1994-06-07T23:59:59.000Z

380

Bipolar pulse field for magnetic refrigeration  

DOE Patents [OSTI]

A magnetic refrigeration apparatus includes first and second steady state magnets, each having a field of substantially equal strength and opposite polarity, first and second bodies made of magnetocaloric material disposed respectively in the influence of the fields of the first and second steady state magnets, and a pulsed magnet, concentric with the first and second steady state magnets, and having a field which cycles between the fields of the first and second steady state magnets, thereby cyclically magnetizing and demagnetizing and thus heating and cooling the first and second bodies. Heat exchange apparatus of suitable design can be used to expose a working fluid to the first and second bodies of magnetocaloric material. A controller is provided to synchronize the flow of working fluid with the changing states of magnetization of the first and second bodies. 2 figs.

Lubell, M.S.

1994-10-25T23:59:59.000Z

Note: This page contains sample records for the topic "magnetism materials surface" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


381

Magnetic switch for reactor control rod. [LMFBR  

DOE Patents [OSTI]

A magnetic reed switch assembly is described for activating an electromagnetic grapple utilized to hold a control rod in position above a reactor core. In normal operation the magnetic field of a permanent magnet is short-circuited by a magnetic shunt, diverting the magnetic field away from the reed switch. The magnetic shunt is made of a material having a Curie-point at the desired release temperature. Above that temperature the material loses its ferromagnetic properties, and the magnetic path is diverted to the reed switch which closes and short-circuits the control circuit for the control rod electro-magnetic grapple which allows the control rod to drop into the reactor core for controlling the reactivity of the core.

Germer, J.H.

1982-09-30T23:59:59.000Z

382

National High Magnetic Field Laboratory - Magnets and Materials...  

Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

Loss Measurements of a Cable-in-Conduit Conductor with Nb3Sn Strands for the High Field Section of the Series-Connected Hybrid Outsert Coil, IEEE Trans. Appl. Supercond., 19 (3,...

383

Pocked surface neutron detector  

DOE Patents [OSTI]

The detection efficiency, or sensitivity, of a neutron detector material such as of Si, SiC, amorphous Si, GaAs, or diamond is substantially increased by forming one or more cavities, or holes, in its surface. A neutron reactive material such as of elemental, or any compound of, .sup.10 B, .sup.6 Li, .sup.6 LiF, U, or Gd is deposited on the surface of the detector material so as to be disposed within the cavities therein. The portions of the neutron reactive material extending into the detector material substantially increase the probability of an energetic neutron reaction product in the form of a charged particle being directed into and detected by the neutron detector material.

McGregor, Douglas (Whitmore Lake, MI); Klann, Raymond (Bolingbrook, IL)

2003-04-08T23:59:59.000Z

384

Materials Scientist  

Broader source: Energy.gov [DOE]

Alternate Title(s):Materials Research Engineer; Metallurgical/Chemical Engineer; Product Development Manager;

385

Permanent Magnetic Materials Discovery | The Ames Laboratory  

Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE:1 First Use of Energy for All Purposes (Fuel and Nonfuel),Feet) Year Jan Feb Mar Apr MayAtmosphericNuclear Security Administration the1 - September 2006 TheSteven AshbyDepartment ofGE'sOptimizationUSING C RAY'S

386

The Li{sub y}Ni{sub 0.2}Mn{sub 0.2}Co{sub 0.6}O{sub 2} electrode materials: A structural and magnetic study  

SciTech Connect (OSTI)

Graphical abstract: EPR signal of the Li{sub 0.6}Co{sub 0.6}Ni{sub 0.2}Mn{sub 0.2}O{sub 2} composition showing that Mn{sup 4+} ions are the solely paramagnetic ions in the structure. Highlights: Black-Right-Pointing-Pointer LiCo{sub 0.6}Ni{sub 0.2}Mn{sub 0.2}O{sub 2} was prepared by the combustion method with sucrose as a fuel. Black-Right-Pointing-Pointer Chemical delithiaition was performed by using NO{sub 2}BF{sub 4} oxidizing agent. Black-Right-Pointing-Pointer The rhombohedral symmetry was preserved upon lithium removal. Black-Right-Pointing-Pointer Lithium extraction leads to Ni{sup 2+} oxidation to Ni{sup 4+} followed by Co{sup 3+} oxidation. Black-Right-Pointing-Pointer The EPR narrow signal of Li{sub 0.6}Co{sub 0.6}Ni{sub 0.2}Mn{sub 0.2}O{sub 2} is due to the only active Mn{sup 4+} ions. -- Abstract: Layered LiNi{sub 0.2}Mn{sub 0.2}Co{sub 0.6}O{sub 2} phase, belonging to a solid solution between LiNi{sub 1/2}Mn{sub 1/2}O{sub 2} and LiCoO{sub 2} most commercialized cathodes, was prepared via the combustion method at 900 Degree-Sign C for a short time (1 h). Structural and magnetic properties of this material during chemical extraction were investigated. The powders adopted the {alpha}-NaFeO{sub 2} structure with almost none of the well-known Li/Ni cation disorder. The analysis of the magnetic properties in the paramagnetic domain agrees with the combination of Ni{sup 2+} (S = 1), Co{sup 3+} (S = 0) and Mn{sup 4+} (S = 3/2) spin-only values. X-ray analysis of the chemically delithiated Li{sub y}Ni{sub 0.2}Mn{sub 0.2}Co{sub 0.6}O{sub 2} reveals no structural transition. The process of lithium extraction from and insertion into LiNi{sub 0.2}Mn{sub 0.2}Co{sub 0.6}O{sub 2} was discussed on the basis of ex situ EPR experiments and magnetic susceptibility. Oxidation of Ni{sup 2+} (S = 1) to Ni{sup 3+} (S = 1/2) and to Ni{sup 4+} (S = 0) was observed upon lithium removal.

Labrini, Mohamed [LCME, FST Marrakech, University Cadi Ayyad, BP549, Av. A. Khattabi, Marrakech (Morocco) [LCME, FST Marrakech, University Cadi Ayyad, BP549, Av. A. Khattabi, Marrakech (Morocco); EEMO, FST Marrakech, University Cadi Ayyad, BP549, Av. A. Khattabi, Marrakech (Morocco); Saadoune, Ismael, E-mail: saadoune1@yahoo.fr [LCME, FST Marrakech, University Cadi Ayyad, BP549, Av. A. Khattabi, Marrakech (Morocco)] [LCME, FST Marrakech, University Cadi Ayyad, BP549, Av. A. Khattabi, Marrakech (Morocco); Almaggoussi, Abdelmajid [EEMO, FST Marrakech, University Cadi Ayyad, BP549, Av. A. Khattabi, Marrakech (Morocco)] [EEMO, FST Marrakech, University Cadi Ayyad, BP549, Av. A. Khattabi, Marrakech (Morocco); Elhaskouri, Jamal [Instituto Universitario de Ciencia de los Materiales, ICMUV Valencia (Spain) [Instituto Universitario de Ciencia de los Materiales, ICMUV Valencia (Spain); Institut de Ciencia dels Materials and Fundacio General, Universitat de Valencia, Amadeu de Savoia - C.P. 46010 Valencia (Spain); Amoros, Pedro [Instituto Universitario de Ciencia de los Materiales, ICMUV Valencia (Spain)] [Instituto Universitario de Ciencia de los Materiales, ICMUV Valencia (Spain)

2012-04-15T23:59:59.000Z

387

Workshop on innovation in materials processing and manufacture: Exploratory concepts for energy applications  

SciTech Connect (OSTI)

The goal of the workshop was to bring together industrial, academic, and DOE Laboratory personnel to discuss and identify potential areas for which creative, innovative, and/or multidisciplinary solutions could result in major payoffs for the nation`s energy economy, DOE, and industry. The topics emphasized in these discussions were: surfaces and interfacial processing technologies, biomolecular materials, powder/precursor technologies, magnetic materials, nanoscale materials, novel ceramics and composites, novel intermetallics and alloys, environmentally benign materials, and energy efficiency. The workshop had a 2-day format. One the first day, there was an introductory session that summarized future directions within DOE`s basic and materials technology programs, and the national studies on manufacturing and materials science and engineering. The balance of the workshop was devoted to brainstorming sessions by seven working groups. During the first working group session, the entire group was divided to discuss topics on: challenges for hostile environments, novel materials in transportation technologies, novel nanoscale materials, and opportunities in biomolecular materials. For the second session, the entire group (except for the working group on biomolecular materials) was reconfigured into new working groups on: alternative pathways to energy efficiency, environmentally benign materials and processes, and waste treatment and reduction: a basic sciences approach. This report contains separate reports from each of the seven working groups.

Horton, L.L. [comp.

1993-06-01T23:59:59.000Z

388

INVESTIGATION OF BREAKDOWN INDUCED SURFACE DAMAGE ON 805 MHZ PILLBOX CAVITY INTERIOR SURFACES  

SciTech Connect (OSTI)

The MuCool Test Area (MTA) at Fermilab is a facility to develop the technology required for ionization cooling for a future Muon Collider and/or Neutrino Factory. As part of this research program, we have tested two 805 MHz vacuum RF cavities in a multi-Tesla magnetic field to study the effects of the static magnetic field on the cavity operation. This study gives useful information on field emitters in the cavity, dark current, surface conditioning, breakdown mechanisms and material properties of the cavity. All these factors determine the maximum accelerating gradient in the cavity. This paper discusses the image processing technique for quantitative estimation of spark damage spot distribution on cavity interior surfaces. The distribution is compared with the electric field distribution predicted by a computer code calculation. The local spark density is proportional to probability of surface breakdown and shows a power law dependence on the maximum electric field (E). This E dependence is consistent with the dark current calculated from the Fowler-Nordheim equation.

Jana, M.R.; Chung, M.; Leonova, M.; Moretti, A.; Tollestrup,A.; Yonehara, K.; Freemire, B.; Torun, Y.; Bowring, D.; Flanagan, G.

2013-09-25T23:59:59.000Z

389

Corrosion protective coating for metallic materials  

DOE Patents [OSTI]

Corrosion protective coatings for metallic materials, particularly aluminum and aluminum alloys, produced with simple, low-cost equipment and materials other than toxic metals or metal salts, or metal cyanides. The metallic material is cleaned, degreased, and deoxidized, the surface is converted to a substantially alkaline condition, and the surface is chemically sealed with inorganic metal compounds.

Buchheit, Rudolph G. (Albuquerque, NM); Martinez, Michael A. (Albuquerque, NM)

1998-01-01T23:59:59.000Z

390

Corrosion protective coating for metallic materials  

DOE Patents [OSTI]

Corrosion protective coatings for metallic materials, particularly aluminum and aluminum alloys, produced with simple, low-cost equipment and materials other than toxic metals or metal salts, or metal cyanides is disclosed. The metallic material is cleaned, degreased, and deoxidized, the surface is converted to a substantially alkaline condition, and the surface is chemically sealed with inorganic metal compounds. 1 fig.

Buchheit, R.G.; Martinez, M.A.

1998-05-26T23:59:59.000Z

391

Magnetic anisotropy in Fe-25Cr-12Co-1Si alloy induced by external magnetic field  

E-Print Network [OSTI]

Magnetic anisotropy in Fe-25Cr-12Co-1Si alloy induced by external magnetic field ZHEN Liang( )1 of Materials Science and Engineering, Harbin Institute of Technology, Harbin 150001, China; 2. Department 27599-3255, USA Received 29 June 2006; accepted 15 January 2007 Abstract: Structural and magnetic

Qin, Lu-Chang

392

Rock magnetic investigation of possible sources of the Bangui magnetic anomaly1 , M., Quesnel2*  

E-Print Network [OSTI]

Rock magnetic investigation of possible sources of the Bangui magnetic anomaly1 2 Ouabego1,2 , M slices of such28 metamorphic rocks, or by an iron-rich mafic source, or by a combination of these two29 source using constraints19 from satellite and ground magnetic field measurements, as well as from surface

Boyer, Edmond

393

Combinatorial synthesis of novel materials  

DOE Patents [OSTI]

Methods and apparatus for the preparation and use of a substrate having an array of diverse materials in predefined regions thereon. A substrate having an array of diverse materials thereon is generally prepared by delivering components of materials to predefined regions on a substrate, and simultaneously reacting the components to form at least two materials. Materials which can be prepared using the methods and apparatus of the present invention include, for example, covalent network solids, ionic solids and molecular solids. More particularly, materials which can be prepared using the methods and apparatus of the present invention include, for example, inorganic materials, intermetallic materials, metal alloys, ceramic materials, organic materials, organometallic materials, non-biological organic polymers, composite materials (e.g., inorganic composites, organic composites, or combinations thereof), etc. Once prepared, these materials can be screened for useful properties including, for example, electrical, thermal, mechanical, morphological, optical, magnetic, chemical, or other properties. Thus, the present invention provides methods for the parallel synthesis and analysis of novel materials having useful properties.

Schultz, Peter G. (Oakland, CA); Xiang, Xiaodong (Alameda, CA); Goldwasser, Isy (Menlo Park, CA)

2001-01-01T23:59:59.000Z

394

Combinatorial synthesis of novel materials  

DOE Patents [OSTI]

Methods and apparatus for the preparation and use of a substrate having an array of diverse materials in predefined regions thereon. A substrate having an array of diverse materials thereon is generally prepared by delivering components of materials to predefined regions on a substrate, and simultaneously reacting the components to form at least two materials. Materials which can be prepared using the methods and apparatus of the present invention include, for example, covalent network solids, ionic solids and molecular solids. More particularly, materials which can be prepared using the methods and apparatus of the present invention include, for example, inorganic materials, intermetallic materials, metal alloys, ceramic materials, organic materials, organometallic materials, non-biological organic polymers, composite materials (e.g., inorganic composites, organic composites, or combinations thereof), etc. Once prepared, these materials can be screened for useful properties including, for example, electrical, thermal, mechanical, morphological, optical, magnetic, chemical, or other properties. Thus, the present invention provides methods for the parallel synthesis and analysis of novel materials having useful properties.

Schultz, Peter G. (Oakland, CA); Xiang, Xiaodong (Alameda, CA); Goldwasser, Isy (Alameda, CA)

2002-02-12T23:59:59.000Z

395

Combinatorial synthesis of novel materials  

DOE Patents [OSTI]

Methods and apparatus for the preparation and use of a substrate having an array of diverse materials in predefined regions thereon. A substrate having an array of diverse materials thereon is generally prepared by delivering components of materials to predefined regions on a substrate, and simultaneously reacting the components to form at least two materials. Materials which can be prepared using the methods and apparatus of the present invention include, for example, covalent network solids, ionic solids and molecular solids. More particularly, materials which can be prepared using the methods and apparatus of the present invention include, for example, inorganic materials, intermetallic materials, metal alloys, ceramic materials, organic materials, organometallic materials, non-biological organic polymers, composite materials (e.g., inorganic composites, organic composites, or combinations thereof), etc. Once prepared, these materials can be screened for useful properties including, for example, electrical, thermal, mechanical, morphological, optical, magnetic, chemical, or other properties. Thus, the present invention provides methods for the parallel synthesis and analysis of novel materials having useful properties.

Schultz, Peter G. (Oakland, CA); Xiang, Xiaodong (Alameda, CA); Goldwasser, Isy (Menlo Park, CA)

1999-12-21T23:59:59.000Z

396

Combinatorial sythesis of organometallic materials  

DOE Patents [OSTI]

Methods and apparatus for the preparation and use of a substrate having an array of diverse materials in predefined regions thereon. A substrate having an array of diverse materials thereon is generally prepared by delivering components of materials to predefined regions on a substrate, and simultaneously reacting the components to form at least two materials. Materials which can be prepared using the methods and apparatus of the present invention include, for example, covalent network solids, ionic solids and molecular solids. More particularly, materials which can be prepared using the methods and apparatus of the present invention include, for example, inorganic materials, intermetallic materials, metal alloys, ceramic materials, organic materials, organometallic materials, non-biological organic polymers, composite materials (e.g., inorganic composites, organic composites, or combinations thereof), etc. Once prepared, these materials can be screened for useful properties including, for example, electrical, thermal, mechanical, morphological, optical, magnetic, chemical, or other properties. Thus, the present invention provides methods for the parallel synthesis and analysis of novel materials having useful properties.

Schultz, Peter G. (Oakland, CA); Xiang, Xiaodong (Alameda, CA); Goldwasser, Isy (Alameda, CA)

2002-07-16T23:59:59.000Z

397

Geotoxic materials in the surface environment  

SciTech Connect (OSTI)

The toxicology and natural occurrence of several recognized geotoxic elements including arsenic, cadmium, chromium, nickel, lead, selenium, uranium, and vanadium is reviewed. The behavior of these elements in the environment and in biological systems is examined. The properties of these eight toxic elements are summarized and presented in a toxicity matrix. The toxicity matrix identifies each of the elements in terms of average crustal abundance, average soil concentration, drinking water standards, irrigation water standards, daily human intake, aquatic toxicity, phytotoxicity, mammalian toxicity, human toxicity, and bioaccumulation factors for fish. Fish are the major aquatic environment contribution to the human diet and bioaccumulation in aquatic ecosystems has been demonstrated to be an important factor in the cycling of elements in aquatic ecosystems. The toxicity matrix is used as a first approximation to rank the geotoxicity of elements for the purpose of focusing future efforts. The ranking from highest to lowest toxicity with respect to the toxicity parameters being discussed is as follows: arsenic, cadmium, lead, selenium, chromium, vanadium, nickel, and uranium.

Koranda, J.J.; Cohen, J.J.; Smith, C.F.; Ciminesi, F.J.

1981-12-07T23:59:59.000Z

398

Effect of oxygen concentration on the magnetic properties of La2CoMnO6 Center for Materials for Information Technology and Department of Chemistry, University of Alabama,  

E-Print Network [OSTI]

Effect of oxygen concentration on the magnetic properties of La2CoMnO6 thin films H. Z. Guo Center; published online 16 November 2007 The dependence of the magnetic properties on oxygen concentration the oxygen background pressure during growth using pulsed laser deposition. Two distinct ferromagnetic FM

Pennycook, Steve

399

weapons material  

National Nuclear Security Administration (NNSA)

2%2A en Office of Weapons Material Protection http:nnsa.energy.govaboutusourprogramsnonproliferationprogramofficesinternationalmaterialprotectionandcooperation-1

400

Studies of Optically Induced Magnetization Dynamics in Colloidal Iron Oxide Nanocrystals  

E-Print Network [OSTI]

Studying dynamics of magnetization relaxation in excited magnetic materials is important both for understanding the rates and pathways of magnetization relaxation and for the potential use in spin-based electronics and data storage devices...

Hsia, Chih-Hao

2011-10-21T23:59:59.000Z

Note: This page contains sample records for the topic "magnetism materials surface" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


401

Structure, Magnetism, and Transport of CuCr2Se4 Thin Films  

E-Print Network [OSTI]

Structure, Magnetism, and Transport of CuCr 2 Se 4 Thindichroism shows that the magnetism persists to the surfacesuch as the nature of magnetism at surfaces and interfaces.

2008-01-01T23:59:59.000Z

402

E-Print Network 3.0 - a-type stars magnetic Sample Search Results  

Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

search results for: a-type stars magnetic Page: << < 1 2 3 4 5 > >> 1 Division of Astronomy and Space Physics Stellar Magnetic Fields Summary: on the surface of a magnetic...

403

Magnetic switch for reactor control rod  

DOE Patents [OSTI]

A magnetic reed switch assembly for activating an electromagnetic grapple utilized to hold a control rod in position above a reactor core. In normal operation the magnetic field of a permanent magnet is short-circuited by a magnetic shunt, diverting the magnetic field away from the reed switch. The magnetic shunt is made of a material having a Curie-point at the desired release temperature. Above that temperature the material loses its ferromagnetic properties, and the magnetic path is diverted to the reed switch which closes and short-circuits the control circuit for the control rod electromagnetic grapple which allows the control rod to drop into the reactor core for controlling the reactivity of the core.

Germer, John H. (San Jose, CA)

1986-01-01T23:59:59.000Z

404

Induced magnetism in Cu nanoparticles embedded in Co P. Swaminathan  

E-Print Network [OSTI]

the effects of changing the nature of confinement to three dimensions by embedding Cu nanoparticles in a Co.1063/1.2806236 Nonmagnetic spacer layers grown between layers of magnetic materials exhibit an induced magnetic moment.1

Weaver, John H.

405

Strange Magnetism  

E-Print Network [OSTI]

We present an analytic and parameter-free expression for the momentum dependence of the strange magnetic form factor of the nucleon and its corresponding radius which has been derived in Heavy Baryon Chiral Perturbation Theory. We also discuss a model-independent relation between the isoscalar magnetic and the strange magnetic form factors of the nucleon based on chiral symmetry and SU(3) only. These limites are used to derive bounds on the strange magnetic moment of the proton from the recent measurement by the SAMPLE collaboration.

Thomas R. Hemmert; Ulf-G. Meissner; Sven Steininger

1998-11-09T23:59:59.000Z

406

Optimized nanoporous materials.  

SciTech Connect (OSTI)

Nanoporous materials have maximum practical surface areas for electrical charge storage; every point in an electrode is within a few atoms of an interface at which charge can be stored. Metal-electrolyte interfaces make best use of surface area in porous materials. However, ion transport through long, narrow pores is slow. We seek to understand and optimize the tradeoff between capacity and transport. Modeling and measurements of nanoporous gold electrodes has allowed us to determine design principles, including the fact that these materials can deplete salt from the electrolyte, increasing resistance. We have developed fabrication techniques to demonstrate architectures inspired by these principles that may overcome identified obstacles. A key concept is that electrodes should be as close together as possible; this is likely to involve an interpenetrating pore structure. However, this may prove extremely challenging to fabricate at the finest scales; a hierarchically porous structure can be a worthy compromise.

Braun, Paul V. (University of Illinois at Urbana-Champaign, Urbana, IL); Langham, Mary Elizabeth; Jacobs, Benjamin W.; Ong, Markus D.; Narayan, Roger J. (North Carolina State University, Raleigh, NC); Pierson, Bonnie E. (North Carolina State University, Raleigh, NC); Gittard, Shaun D. (North Carolina State University, Raleigh, NC); Robinson, David B.; Ham, Sung-Kyoung (Korea Basic Science Institute, Gangneung, South Korea); Chae, Weon-Sik (Korea Basic Science Institute, Gangneung, South Korea); Gough, Dara V. (University of Illinois at Urbana-Champaign, Urbana, IL); Wu, Chung-An Max; Ha, Cindy M.; Tran, Kim L.

2009-09-01T23:59:59.000Z

407

Magnetic Field Safety Magnetic Field Safety  

E-Print Network [OSTI]

Magnetic Field Safety Training #12;Magnetic Field Safety Strong Magnetic Fields exist around energized magnets. High magnetic fields alone are a recognized hazard only for personnel with certain medical conditions such as pacemakers, magnetic implants, or embedded shrapnel. In addition, high magnetic

McQuade, D. Tyler

408

Superconductive imaging surface magnetometer  

DOE Patents [OSTI]

An improved pick-up coil system for use with Superconducting Quantum Interference Device gradiometers and magnetometers involving the use of superconducting plates near conventional pick-up coil arrangements to provide imaging of nearby dipole sources and to deflect environmental magnetic noise away from the pick-up coils. This allows the practice of gradiometry and magnetometry in magnetically unshielded environments. One embodiment uses a hemispherically shaped superconducting plate with interior pick-up coils, allowing brain wave measurements to be made on human patients. another embodiment using flat superconducting plates could be used in non-destructive evaluation of materials.

Overton, Jr., William C. (Los Alamos, NM); van Hulsteyn, David B. (Santa Fe, NM); Flynn, Edward R. (Los Alamos, NM)

1991-01-01T23:59:59.000Z

409

pH dependence of the electrochemical behavior of surfaces modified with a polymer derived from a monomer consisting of two viologen subunits linked by a quinone: evidence for rectification by synthetic molecular materials  

SciTech Connect (OSTI)

The authors report results concerning use of the surface-derivatizing reagent I that demonstrates a kind of rectification that is important in systems such as the photosynthetic apparatus. The important finding is that an electrode-bound redox polymer formed via hydrolysis of the Si-OMe bonds if O, (BV-Q-BV/sup 6 +/)/sub n/, undergoes a 4e/sup -//2H/sup +/ reduction, but below pH 5 only 2e/sup -/ can be electrochemically withdrawn from the reduced material. Reduction of quinone centers, Q, in the (BV-Q-BV/sup 6 +/)/sub n/ polymer to their dihydroxy form, QH/sub 2/, is mediated by the viologen, BV/sup 2+/+/, redox system, but the process cannot be reversed at low pH because the QH/sub 2/ is thermodynamically incapable of delivering charge back to the BV/sup 2 +/ centers. Direct equilibration of the electrode with the Q/QH/sub 2/ centers in the (BV-Q-BV/sup 6 +/)/sub n/ polymer does not occur. Relevance of the new finding to systems like the photosynthetic apparatus rests in the fact that charge separation in the photosynthetic system is achieved by a kind of rectification: the charge transport process involves a series of effectively unidirectional e/sup -/ transfer events.

Smith, D.K.; Lane, G.A.; Wrighton, M.S.

1986-06-11T23:59:59.000Z

410

LDRD-LW Final Report: 07-LW-041 "Magnetism in Semiconductor Nanocrystals: New Physics at the Nanoscale"  

SciTech Connect (OSTI)

The work conducted in this project was conducted with the aim of identifying and understanding the origin and mechanisms of magnetic behavior in undoped semiconductor nanocrystals (NCs), specifically those composed of CdSe. It was anticipated that the successful completion of this task would have the effect of addressing and resolving significant controversy over this topic in the literature. Meanwhile, application of the resultant knowledge was expected to permit manipulation of the magnetic properties, particularly the strength of any magnetic effects, which is of potential relevance in a range of advanced technologies. More specifically, the project was designed and research conducted with the goal of addressing the following series of questions: (1) How does the magnitude of the magnetism in CdSe NCs change with the organic molecules used to passivate their surface the NC size? i.e. Is the magnetism an intrinsic effect in the nanocrystalline CdSe (as observed for Au NCs) or a surface termination driven effect? (2) What is the chemical (elemental) nature of the magnetism? i.e. Are the magnetic effects associated with the Cd atoms or the Se atoms or both? (3) What is/are the underlying mechanism(s)? (4) How can the magnetism be controlled for further applications? To achieve this goal, several experimental/technical milestones were identified to be fulfilled during the course of the research: (A) The preparation of well characterized CdSe NCs with varying surface termination (B) Establishing the extent of the magnetism of these NCs using magnetometry (particularly using superconducting interference device [SQUID]) (C) Establishing the chemical nature of the magnetism using x-ray magnetic circular dichroism (XMCD) - the element specific nature of the technique allows identification of the element responsible for the magnetism (D) Identification of the effect of surface termination on the empty densities of states (DOS) using x-ray absorption spectroscopy (XAS), with particular emphasis on elucidating small changes in the d-electron count. Characterizing changes in the d-electron density can yield important insight into the mechanisms of magnetism in materials. As the three attached manuscripts illustrate (presented in preprint form to ensure no infringement of copyright), each of these milestones was successfully illustrated and the results published in the scientific literature during the course of the project. The research team members were able to determine, from a series of XAS, XMCD and SQUID magnetometry measurements, that CdSe NCs are paramagnetic and that the magnitude of magnetic susceptibility is dependent upon the type of organic molecule used to passivate the NC surface (i.e. the observed magnetism results, at least in part, from a surface effect that is not intrinsic to the NCs). In addition, they identified that the mechanism by which the magnetic susceptibility is modified - via {pi} back-donation of d-electrons to the organic ligands from the Cd atoms. These findings demonstrate that the magnetic properties are related to the surface Cd atoms and illustrate the means by which the magnetic behavior can be manipulated for specific technological applications. Two of the papers published during the course of the LW project do not contain magnetometry data, but focus on the evolution in electronic structure of the CdSe NCs as a function of particle size. These measurements were crucial in developing an understanding of the electronic behavior of the NCs and, ultimately, in assigning the p back-donation mechanism for inducing controllable paramagnetic behavior. Significantly, the research team has also filed a patent application based upon their research: 'Method for Creating Ligand Induced Paramagnetism in Nanocrystalline Structures' Docket: IL-11858. It is noted that both LDRD-LW and Office of Basic Energy Sciences (OBES) funding is acknowledged in the attached manuscripts. As such, is important to indicate that funds were not comingled during the course of the project. Some of the experimental data presente

Meulenberg, R W; Lee, J I; McCall, S K

2009-10-19T23:59:59.000Z

411

Many-body Interactions in Magnetic Films and Nanostructures  

SciTech Connect (OSTI)

We describe results supported by DOE grant DE-FG02-04ER46158, which focused on magnetic interaction at surfaces, in thin films, and in metallic nanostructures. We report on three general topics: 1) The Rashba spin splitting at magnetic surfaces of rare earth metals, 2) magnetic nanowires self-assembled on stepped tungsten single crystals, and 3) magnetic interaction in graphene films doped with hydrogen atoms.

Stephen D. Kevan

2012-12-12T23:59:59.000Z

412

Magnetic nanoparticles for applications in oscillating magnetic field  

SciTech Connect (OSTI)

Enzymatic and thermochemical catalysis are both important industrial processes. However, the thermal requirements for each process often render them mutually exclusive: thermochemical catalysis requires high temperature that denatures enzymes. One of the long-term goals of this project is to design a thermocatalytic system that could be used with enzymatic systems in situ to catalyze reaction sequences in one pot; this system would be useful for numerous applications e.g. conversion of biomass to biofuel and other commodity products. The desired thermocatalytic system would need to supply enough thermal energy to catalyze thermochemical reactions, while keeping the enzymes from high temperature denaturation. Magnetic nanoparticles are known to generate heat in an oscillating magnetic field through mechanisms including hysteresis and relaxational losses. We envisioned using these magnetic nanoparticles as the local heat source embedded in sub-micron size mesoporous support to spatially separate the particles from the enzymes. In this study, we set out to find the magnetic materials and instrumental conditions that are sufficient for this purpose. Magnetite was chosen as the first model magnetic material in this study because of its high magnetization values, synthetic control over particle size, shape, functionalization and proven biocompatibility. Our experimental designs were guided by a series of theoretical calculations, which provided clues to the effects of particle size, size distribution, magnetic field, frequency and reaction medium. Materials of theoretically optimal size were synthesized, functionalized, and their effects in the oscillating magnetic field were subsequently investigated. Under our conditions, the materials that clustered e.g. silica-coated and PNIPAM-coated iron oxides exhibited the highest heat generation, while iron oxides embedded in MSNs and mesoporous iron oxides exhibited the least bulk heating. It is worth noting that the specific loss power of PNIPAM-coated Fe{sub 3}O{sub 4} was peculiarly high, and the heat loss mechanism of this material remains to be elucidated. Since thermocatalysis is a long-term goal of this project, we also investigated the effects of the oscillating magnetic field system for the synthesis of 7-hydroxycoumarin-3-carboxylic acid. Application of an oscillating magnetic field in the presence of magnetic particles with high thermal response was found to effectively increase the reaction rate of the uncatalyzed synthesis of the coumarin derivative compared to the room temperature control.

Peeraphatdit, Chorthip

2010-12-15T23:59:59.000Z

413

Method of passivating semiconductor surfaces  

DOE Patents [OSTI]

A method of passivating Group III-V or II-VI semiconductor compound surfaces. The method includes selecting a passivating material having a lattice constant substantially mismatched to the lattice constant of the semiconductor compound. The passivating material is then grown as an ultrathin layer of passivating material on the surface of the Group III-V or II-VI semiconductor compound. The passivating material is grown to a thickness sufficient to maintain a coherent interface between the ultrathin passivating material and the semiconductor compound. In addition, a device formed from such method is also disclosed.

Wanlass, Mark W. (Golden, CO)

1990-01-01T23:59:59.000Z

414

Method of passivating semiconductor surfaces  

SciTech Connect (OSTI)

A method is described for passivating Group III-V or II-VI semiconductor compound surfaces. The method includes selecting a passivating material having a lattice constant substantially mismatched to the lattice constant of the semiconductor compound. The passivating material is then grown as an ultrathin layer of passivating material on the surface of the Group III-V or II-VI semiconductor compound. The passivating material is grown to a thickness sufficient to maintain a coherent interface between the ultrathin passivating material and the semiconductor compound. In addition, a device formed from such method is also disclosed.

Wanlass, M.W.

1990-06-19T23:59:59.000Z

415

Mechanics of abrasive wear of elastomeric materials  

E-Print Network [OSTI]

Elastomeric materials are widely used as tire and sealing materials due to their ability to undergo large deformations and conform to the mating surface. However, their applications often result in repeated contact with ...

Qi, Hang, 1971-

2003-01-01T23:59:59.000Z

416

Electric control of magnetization relaxation in thin film magnetic insulators.  

SciTech Connect (OSTI)

Control of magnetization relaxation in magnetic insulators via interfacial spin scattering is demonstrated. The experiments use nanometer-thick yttrium iron garnet (YIG)/Pt layered structures, with the Pt layer biased by an electric voltage. The bias voltage produces a spin current across the Pt thickness. As this current scatters off the YIG surface, it exerts a torque on the YIG surface spins. This torque can reduce or enhance the damping and thereby decrease or increase the ferromagnetic resonance linewidth of the YIG film, depending on the field/current configuration.

Wang, Z.; Sun, Y.; Song, Y-Y.; Wu, M.; Schultheiss, H.; Pearson, J. E.; Hoffmann, A. (Materials Science Division); (Colorado State Univ.)

2011-10-01T23:59:59.000Z

417

Materials Sciences Division 1990 annual report  

SciTech Connect (OSTI)

This report is the Materials Sciences Division`s annual report. It contains abstracts describing materials research at the National Center for Electron Microscopy, and for research groups in metallurgy, solid-state physics, materials chemistry, electrochemical energy storage, electronic materials, surface science and catalysis, ceramic science, high tc superconductivity, polymers, composites, and high performance metals.

Not Available

1990-12-31T23:59:59.000Z

418

Materials Sciences Division 1990 annual report  

SciTech Connect (OSTI)

This report is the Materials Sciences Division's annual report. It contains abstracts describing materials research at the National Center for Electron Microscopy, and for research groups in metallurgy, solid-state physics, materials chemistry, electrochemical energy storage, electronic materials, surface science and catalysis, ceramic science, high tc superconductivity, polymers, composites, and high performance metals.

Not Available

1990-01-01T23:59:59.000Z

419

Scientists Connect Thermoelectric Materials and Topological Insulators...  

Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

and relativity in combination produce a unique conducting state on the surface. Excellent thermoelectric performance depends on a material having both high conductivity and high...

420

Scintillator material  

DOE Patents [OSTI]

An improved scintillator material comprising cerium fluoride is disclosed. Cerium fluoride has been found to provide a balance of good stopping power, high light yield and short decay constant that is superior to known scintillator materials such as thallium-doped sodium iodide, barium fluoride and bismuth germanate. As a result, cerium fluoride is favorably suited for use as a scintillator material in positron emission tomography. 4 figs.

Anderson, D.F.; Kross, B.J.

1992-07-28T23:59:59.000Z

Note: This page contains sample records for the topic "magnetism materials surface" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


421

Scintillator material  

DOE Patents [OSTI]

An improved scintillator material comprising cerium fluoride is disclosed. Cerium fluoride has been found to provide a balance of good stopping power, high light yield and short decay constant that is superior to known scintillator materials such as thallium-doped sodium iodide, barium fluoride and bismuth germanate. As a result, cerium fluoride is favorably suited for use as a scintillator material in positron emission tomography. 4 figs.

Anderson, D.F.; Kross, B.J.

1994-06-07T23:59:59.000Z

422

Scintillator material  

DOE Patents [OSTI]

An improved scintillator material comprising cerium fluoride is disclosed. Cerium fluoride has been found to provide a balance of good stopping power, high light yield and short decay constant that is superior to known scintillator materials such as thallium-doped sodium iodide, barium fluoride and bismuth germanate. As a result, cerium fluoride is favorably suited for use as a scintillator material in positron emission tomography.

Anderson, David F. (Batavia, IL); Kross, Brian J. (Aurora, IL)

1992-01-01T23:59:59.000Z

423

Scintillator material  

DOE Patents [OSTI]

An improved scintillator material comprising cerium fluoride is disclosed. Cerium fluoride has been found to provide a balance of good stopping power, high light yield and short decay constant that is superior to known scintillator materials such as thallium-doped sodium iodide, barium fluoride and bismuth germanate. As a result, cerium fluoride is favorably suited for use as a scintillator material in positron emission tomography.

Anderson, David F. (Batavia, IL); Kross, Brian J. (Aurora, IL)

1994-01-01T23:59:59.000Z

424

Critical Materials:  

Broader source: Energy.gov (indexed) [DOE]

lighting. 14 (bottom) Criticality ratings of shortlisted raw 76 materials. 15 77 2. Technology Assessment and Potential 78 This section reviews the major trends within...

425

Direct torsional actuation of microcantilevers using magnetic excitation  

SciTech Connect (OSTI)

Torsional mode dynamic force microscopy can be used for a wide range of studies including mapping lateral contact stiffness, torsional frequency or amplitude modulation imaging, and dynamic friction measurements of various materials. Piezo-actuation of the cantilever is commonly used, but it introduces spurious resonances, limiting the frequency range that can be sampled, and rendering the technique particularly difficult to apply in liquid medium where the cantilever oscillations are significantly damped. Here, we demonstrate a method that enables direct torsional actuation of cantilevers with high uniformity over wide frequency ranges by attaching a micrometer-scale magnetic bead on the back side of the cantilever. We show that when beads are magnetized along the width of the cantilever, efficient torsional actuation of the cantilevers can be achieved using a magnetic field produced from a solenoid placed underneath the sample. We demonstrate the capability of this technique by imaging atomic steps on graphite surfaces in tapping mode near the first torsional resonance of the cantilever in dodecane. The technique is also applied to map the variations in the lateral contact stiffness on the surface of graphite and polydiacetylene monolayers.

Gosvami, Nitya Nand; Nalam, Prathima C.; Tam, Qizhan; Carpick, Robert W., E-mail: carpick@seas.upenn.edu [Department of Mechanical Engineering and Applied Mechanics, University of Pennsylvania, Philadelphia, Pennsylvania 19104 (United States); Exarhos, Annemarie L.; Kikkawa, James M. [Department of Physics and Astronomy, University of Pennsylvania, Philadelphia, Pennsylvania 19104 (United States)

2014-09-01T23:59:59.000Z

426

Intense Magnetized Plasma-Wall Interaction  

SciTech Connect (OSTI)

This research project studied wall-plasma interactions relevant to fusion science. Such interactions are a critical aspect of Magneto-Inertial Fusion (MIF) because flux compression by a pusher material, in particular the metal for the liner approach to MIF, involves strong eddy current heating on the surface of the pusher, and probably interactions and mixing of the pusher with the interior fuel during the time when fusion fuel is being burned. When the pusher material is a metal liner, high-energy-density conditions result in fascinating behavior. For example, "warm dense matter" is produced, for which material properties such as resistivity and opacity are not well known. In this project, the transformation into plasma of metal walls subjected to pulsed megagauss magnetic fields was studied with an experiment driven by the UNR 1 MA Zebra generator. The experiment was numerically simulated with using the MHRDR code. This simple, fundamental high-energy-density physics experiment, in a regime appropriate to MIF, has stimulated an important and fascinating comparison of numerical modeling codes and tables with experiment. In addition, we participated in developing the FRCHX experiment to compress a field-reversed-configuration (FRC) plasma with a liner, in collaboration with researchers from Air Force Research Laboratory and Los Alamos National Lab, and we helped develop diagnostics for the Plasma Liner Experiment (PLX) at LANL. Last, but not least, this project served to train students in high-energy-density physics.

Bauer, Bruno S. [UNR] [UNR; Fuelling, Stephan [UNR] [UNR

2013-11-30T23:59:59.000Z

427

Department of Advanced Materials Science  

E-Print Network [OSTI]

device, Bioconjugate matsuura@k.u-tokyo.ac.jpe-mail 04-7136-3781T E L Environmental-friendly materials Nuclear magnetic resonance, Quantum spin systems, Low temperature physics, Strongly correlated electron Effect takatama@spring8.or.jpe-mail 0791-58-2942T E L Synchrotron Radiation, X-ray Free Electron Laser

Katsumoto, Shingo

428

Chemical Functionalization of Nanostructured Materials Using Supercritical Reaction Media  

SciTech Connect (OSTI)

There exists a need for durable and thin functional coatings to utilize the afforded surface area of highly porous ceramic materials. Deposition of silane-based Self Assembled Monolayers (SAMs) has thus far been limited to maximum coverages of 4-5 molecules/nm2 and long processing times (up to 2 weeks), due to the restricted internal geometry of the substrates. Results are presented for SAMs deposited on high surface area silica from supercritical fluids (SCFs). The SAMs so produced display unprecedented coverages, high monolayer integrity, and extremely low surface defect density. Moreover, the depositions and subsequent removal of reaction byproducts are complete in a matter of minutes rather than days. Nuclear Magnetic Resonance (NMR) spectra of the surface modified silica are presented, demonstrating the SAM integrity and evolution over time. Sorption of aqueous metal ions is demonstrated, and results are given demonstrating the broad pH stability of the deposited SAMs. A chemical explanation for the enhanced deposition is posited, and the kinetics of mass transport into and out of the nanostructured spaces are discussed.Related experiments using zeolite substrates show deposition of thiol-terminated silanes to internal surfaces of 6? microporous material. After oxidation of the thiol functional group size selective chemistry was demonstrated using the produced catalyst, proving the efficacy of the supercritical reaction medium for installing functional coatings inside pores of similar diameters to the chain length of the deposited molecule[]. Comparisons are made between the response of the different substrates to the supercritical fluid-based processing, and remarks on the utility of SCF based processing of nanostructured materials are presented.

Zemanian, Thomas S.; Fryxell, Glen E.; Liu, Jun; Mattigod, Shas V.; Shin, Yongsoon; Franz, James A.; Ustyugov, Oleksiy A.; Nie, Zimin

2001-12-15T23:59:59.000Z

429

Magnetism and superconductivity driven by identical 4f states in a heavy-fermion metal  

SciTech Connect (OSTI)

The apparently inimical relationship between magnetism and superconductivity has come under increasing scrutiny in a wide range of material classes, where the free energy landscape conspires to bring them in close proximity to each other. Particularly enigmatic is the case when these phases microscopically interpenetrate, though the manner in which this can be accomplished remains to be fully comprehended. Here, we present combined measurements of elastic neutron scattering, magnetotransport, and heat capacity on a prototypical heavy fermion system, in which antiferromagnetism and superconductivity are observed. Monitoring the response of these states to the presence of the other, as well as to external thermal and magnetic perturbations, points to the possibility that they emerge from different parts of the Fermi surface. Therefore, a single 4f state could be both localized and itinerant, thus accounting for the coexistence of magnetism and superconductivity.

Thompson, Joe E [Los Alamos National Laboratory; Nair, S [MAX PLANCK INST.; Stockert, O [MAX PLANCK INST.; Witte, U [INST. FUR FESTKORPERPHYSIK; Nicklas, M [MAX PLANCK INST.; Schedler, R [HELMHOLTZ - ZENTRUM; Bianchi, A [UC, IRVINE; Fisk, Z [UC, IRVINE; Wirth, S [MAX PLANCK INST.; Steglich, K [HELMHOLTZ - ZENTRUM

2009-01-01T23:59:59.000Z

430

Flow Components in a NaK Test Loop Designed to Simulate Conditions in a Nuclear Surface Power Reactor  

SciTech Connect (OSTI)

A test loop using NaK as the working fluid is presently in use to study material compatibility effects on various components that comprise a possible nuclear reactor design for use on the lunar surface. A DC electromagnetic (EM) pump has been designed and implemented as a means of actively controlling the NaK flow rate through the system and an EM flow sensor is employed to monitor the developed flow rate. These components allow for the matching of the flow rate conditions in test loops with those that would be found in a full-scale surface-power reactor. The design and operating characteristics of the EM pump and flow sensor are presented. In the EM pump, current is applied to a set of electrodes to produce a Lorentz body force in the fluid. A measurement of the induced voltage (back-EMF) in the flow sensor provides the means of monitoring flow rate. Both components are compact, employing high magnetic field strength neodymium magnets thermally coupled to a water-cooled housing. A vacuum gap limits the heat transferred from the high temperature NaK tube to the magnets and a magnetically-permeable material completes the magnetic circuit. The pump is designed to produce a pressure rise of 34.5 kPa, and the flow sensor's predicted output is roughly 20 mV at the loop's nominal flow rate of 0.114 m{sup 3}/hr.

Polzin, Kurt A.; Godfroy, Thomas J. [NASA Marshall Space Flight Center Propulsion Research and Technology Applications Branch/ER24, MSFC, AL 35812 (United States)

2008-01-21T23:59:59.000Z

431

High magnetic field processing of liquid crystalline polymers  

DOE Patents [OSTI]

A process of forming bulk articles of oriented liquid crystalline thermoset material, the material characterized as having an enhanced tensile modulus parallel to orientation of an applied magnetic field of at least 25 percent greater than said material processed in the absence of a magnetic field, by curing a liquid crystalline thermoset precursor within a high strength magnetic field of greater than about 2 Tesla, is provided, together with a resultant bulk article of a liquid crystalline thermoset material, said material processed in a high strength magnetic field whereby said material is characterized as having a tensile modulus parallel to orientation of said field of at least 25 percent greater than said material processed in the absence of a magnetic field.

Smith, Mark E. (Los Alamos, NM); Benicewicz, Brian C. (Los Alamos, NM); Douglas, Elliot P. (Los Alamos, NM)

1998-01-01T23:59:59.000Z

432

High magnetic field processing of liquid crystalline polymers  

DOE Patents [OSTI]

A process of forming bulk articles of oriented liquid crystalline thermoset material, the material characterized as having an enhanced tensile modulus parallel to orientation of an applied magnetic field of at least 25 percent greater than said material processed in the absence of a magnetic field, by curing a liquid crystalline thermoset precursor within a high strength magnetic field of greater than about 2 Tesla, is provided, together with a resultant bulk article of a liquid crystalline thermoset material, said material processed in a high strength magnetic field whereby said material is characterized as having a tensile modulus parallel to orientation of said field of at least 25 percent greater than said material processed in the absence of a magnetic field.

Smith, M.E.; Benicewicz, B.C.; Douglas, E.P.

1998-11-24T23:59:59.000Z

433

Fabrication of thin films for a small alternating gradient field magnetometer for biomedical magnetic sensing applications  

E-Print Network [OSTI]

. This is due to the addition of Cr, which decreases the magnetic moment of the films; magnetoelas- tic coupling magnetometers (AGFM) composed of permanent magnets are being developed for measuring magnetic moments in soil Si membrane with a cylindrical SmCo permanent magnet.2,3 The magnetic material attached

McHenry, Michael E.

434

Saturable inductor and transformer structures for magnetic pulse compression  

DOE Patents [OSTI]

Saturable inductor and transformer for magnetic compression of an electronic pulse, using a continuous electrical conductor looped several times around a tightly packed core of saturable inductor material.

Birx, Daniel L. (Londonderry, NH); Reginato, Louis L. (Orinda, CA)

1990-01-01T23:59:59.000Z

435

Magnetic reconnection launcher  

DOE Patents [OSTI]

An electromagnetic launcher includes a plurality of electrical stages which are energized sequentially in the launcher with the passage of a projectiles. Each stage of the launcher includes two or more coils which are arranged coaxially on either closed-loop or straight lines to form gaps between their ends. The projectile has an electrically conductive gap-portion that passes through all the gaps of all the stages in a direction transverse to the axes of the coils. The coils receive an electric current, store magnetic energy, and convert a significant portion of the stored magnetic energy into kinetic energy of the projectile moves through the gap. The magnetic polarity of the opposing coils is in the same direction, e.g. N-S-N-S. A gap portion of the projectile may be made from aluminum and is propelled by the reconnection of magnetic flux stored in the coils which causes accelerating forces to act upon the projectile and at the horizontal surfaces of the projectile near its rear. The gap portion of the projectile may be flat, rectangular and longer than the length of the opposing coils. The gap portion of the projectile permits substantially unrestricted distribution of the induced currents so that current densities are only high where the useful magnetic force is high. This allows designs which permit ohmic oblation from the rear surfaces of the gap portion of the projectile allowing much high velocities to be achieved. An electric power apparatus controls the electric power supplied to the opposing coils until the gap portion of the projectile substantially occupies the gap between the coils, at which time the coils are supplied with peak current quickly. 8 figs.

Cowan, M.

1987-04-06T23:59:59.000Z

436

Laser Plasma Material Interactions  

SciTech Connect (OSTI)

Surface treatment by means of pulsed laser beams in reactive atmospheres is an attractive technique to enhance the surface features, such as corrosion and wear resistance or the hardness. Many carbides and nitrides play an important role for technological applications, requiring the mentioned property improvements. Here we present a new promising fast, flexible and clean technique for a direct laser synthesis of carbide and nitride surface films by short pulsed laser irradiation in reactive atmospheres (e.g. methane, nitrogen). The corresponding material is treated by short intense laser pulses involving plasma formation just above the irradiated surface. Gas-Plasma-Surface reactions lead to a fast incorporation of the gas species into the material and subsequently the desired coating formation if the treatment parameters are chosen properly. A number of laser types have been used for that (Excimer Laser, Nd:YAG, Ti:sapphire, Free Electron Laser) and a number of different nitride and carbide films have been successfully produced. The mechanisms and some examples will be presented for Fe treated in nitrogen and Si irradiated in methane.

Schaaf, Peter; Carpene, Ettore [Universitaet Goettingen, II. Physikalisches Institut, Friedrich-Hund-Platz 1, 37077 Goettingen (Germany)

2004-12-01T23:59:59.000Z

437

Cermet materials  

DOE Patents [OSTI]

A self-cleaning porous cermet material, filter and system utilizing the same may be used in filtering particulate and gaseous pollutants from internal combustion engines having intermetallic and ceramic phases. The porous cermet filter may be made from a transition metal aluminide phase and an alumina phase. Filler materials may be added to increase the porosity or tailor the catalytic properties of the cermet material. Additionally, the cermet material may be reinforced with fibers or screens. The porous filter may also be electrically conductive so that a current may be passed therethrough to heat the filter during use. Further, a heating element may be incorporated into the porous cermet filter during manufacture. This heating element can be coated with a ceramic material to electrically insulate the heating element. An external heating element may also be provided to heat the cermet filter during use.

Kong, Peter C. (Idaho Falls, ID)

2008-12-23T23:59:59.000Z

438

Surface Soil  

Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

Surface Soil Surface Soil We compare local soil samples with samples collected from northern New Mexico locations that are beyond the range of potential influence from normal...

439

Materials Under Extremes | ORNL  

Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE:1 First Use of Energy for All Purposes (Fuel and Nonfuel),Feet) Year Jan Feb Mar Apr MayAtmospheric Optical Depth7-1D: VegetationEquipment Surfaces andMapping the Nanoscale LandscapeImports 5.90Materials Porous Materials

440

Low dimensional magnetism  

E-Print Network [OSTI]

Magnetism in Ultracold Gases 4 Magnetic phase diagram of aMagnetism . . . . . . . . . . . .1.3 Magnetism in condensedIntroduction 1 Brief introduction to magnetism 1.1 Classic

Kjall, Jonas Alexander

2012-01-01T23:59:59.000Z

Note: This page contains sample records for the topic "magnetism materials surface" from the National Library of EnergyBeta (NLEBeta).
While these samples are representative of the content of NLEBeta,
they are not comprehensive nor are they the most current set.
We encourage you to perform a real-time search of NLEBeta
to obtain the most current and comprehensive results.


441

Organic materials for fusion-reactor applications  

SciTech Connect (OSTI)

Organic materials requirements for fusion-reactor magnets are described with reference to the temperature, radiation, and electrical and mechanical stress environment expected in these magnets. A review is presented of the response to gamma-ray and neutron irradiation at low temperatures of candidate organic materials; i.e. laminates, thin films, and potting compounds. Lifetime-limiting features of this response as well as needed testing under magnet operating conditions not yet adequately investigated are identified and recomendations for future work are made.

Hurley, G.F.; Coltman, R.R. Jr.

1983-09-01T23:59:59.000Z

442

Anchored nanostructure materials and method of fabrication  

DOE Patents [OSTI]

Anchored nanostructure materials and methods for their fabrication are described. The anchored nanostructure materials may utilize nano-catalysts that include powder-based or solid-based support materials. The support material may comprise metal, such as NiAl, ceramic, a cermet, or silicon or other metalloid. Typically, nanoparticles are disposed adjacent a surface of the support material. Nanostructures may be formed as anchored to nanoparticles that are adjacent the surface of the support material by heating the nano-catalysts and then exposing the nano-catalysts to an organic vapor. The nanostructures are typically single wall or multi-wall carbon nanotubes.

Seals, Roland D; Menchhofer, Paul A; Howe, Jane Y; Wang, Wei

2012-11-27T23:59:59.000Z

443

Permanent magnet edge-field quadrupole  

DOE Patents [OSTI]

Planar permanent magnet edge-field quadrupoles for use in particle accelerating machines and in insertion devices designed to generate spontaneous or coherent radiation from moving charged particles are disclosed. The invention comprises four magnetized rectangular pieces of permanent magnet material with substantially similar dimensions arranged into two planar arrays situated to generate a field with a substantially dominant quadrupole component in regions close to the device axis. 10 figs.

Tatchyn, R.O.

1997-01-21T23:59:59.000Z

444

HIGH-FIELD SUPERCONDUCTING ACCELERATOR MAGNETS  

E-Print Network [OSTI]

D. C. 'Niobium-Titanium Superconducting Material s ', in S.Nb -Ti and Nb3Sn superconductors. , •• ,""" s. S. Clamp, Tie14, 1982 HIGH-FIELD SUPERCONDUCTING ACCELERATOR MAGNETS C.

Taylor, C.

2011-01-01T23:59:59.000Z

445

A Small Scale Magnetic Particle Relaxometer  

E-Print Network [OSTI]

Magnetic Particle Imaging (MPI) is a newly found imaging modality. It utilizes superparamagnetic materials as tracers in the blood stream to obtain very high resolutions. MPI promises to have high sensitivity, high spatial resolution...

El Ghamrawy, Ahmed

2013-12-09T23:59:59.000Z

446

Lunar magnetic field measurements with a cubesat  

E-Print Network [OSTI]

We have developed a mission concept that uses 3-unit cubesats to perform new measurements of lunar magnetic fields, less than 100 meters above the Moon’s surface. The mission calls for sending the cubesats on impact ...

Garrick-Bethell, Ian

447

Controlling Magnetism at the Nanoscale  

E-Print Network [OSTI]

Manipulation of Magnetism - External148 Conclusion A The Magnetism Cheat Sheet A.1 Magnetic157 A.2 Magnetism Unit Conversion

Wong, Jared

2012-01-01T23:59:59.000Z

448

Understanding Automotive Exhaust Catalysts Using a Surface Science...  

Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

Automotive Exhaust Catalysts Using a Surface Science Approach: Model NOx Storage Materials. Understanding Automotive Exhaust Catalysts Using a Surface Science Approach: Model NOx...

449

Ternary Dy-Er-Al magnetic refrigerants  

DOE Patents [OSTI]

A ternary magnetic refrigerant material comprising (Dy{sub 1{minus}x}Er{sub x})Al{sub 2} for a magnetic refrigerator using the Joule-Brayton thermodynamic cycle spanning a temperature range from about 60K to about 10K, which can be adjusted by changing the Dy to Er ratio of the refrigerant. 29 figs.

Gschneidner, K.A. Jr.; Takeya, Hiroyuki

1995-07-25T23:59:59.000Z

450

Ternary Dy-Er-Al magnetic refrigerants  

DOE Patents [OSTI]

A ternary magnetic refrigerant material comprising (Dy.sub.1-x Er.sub.x)Al.sub.2 for a magnetic refrigerator using the Joule-Brayton thermodynamic cycle spanning a temperature range from about 60K to about 10K, which can be adjusted by changing the Dy to Er ratio of the refrigerant.

Gschneidner, Jr., Karl A. (Ames, IA); Takeya, Hiroyuki (Ibaraki, JP)

1995-07-25T23:59:59.000Z

451

A New First-Principles Calculation of Field-Dependent RF Surface Impedance of BCS Superconductor  

SciTech Connect (OSTI)

There is a need to understand the intrinsic limit of radiofrequency (RF) surface impedance that determines the performance of superconducting RF cavities in particle accelerators. Here we present a field-dependent derivation of Mattis-Bardeen theory of the RF surface impedance of BCS superconductors based on the shifted density of states resulting from coherently moving Cooper pairs. Our theoretical prediction of the effective BCS RF surface resistance (Rs) of niobium as a function of peak surface magnetic field amplitude agrees well with recently reported record low loss resonant cavity measurements from JLab and FNAL with carefully, yet differently, prepared niobium material. The surprising reduction in resistance with increasing field is explained to be an intrinsic effect.

Xiao, Binping [Brookhaven National Laboratory, Upton, New York (United States); Reece, Charles E. [Thomas Jefferson National Accelerator Facility, Newport News, VA (United States)

2014-02-01T23:59:59.000Z

452

Hydrogen Burning on Magnetar Surfaces  

E-Print Network [OSTI]

We compute the rate of diffusive nuclear burning for hydrogen on the surface of a "magnetar" (Soft Gamma-Ray Repeater or Anomalous X-Ray Pulsar). We find that hydrogen at the photosphere will be burned on an extremely rapid timescale of hours to years, depending on composition of the underlying material. Improving on our previous studies, we explore the effect of a maximally thick "inert" helium layer, previously thought to slow down the burning rate. Since hydrogen diffuses faster in helium than through heavier elements, we find this helium buffer actually increases the burning rate for magnetars. We compute simple analytic scalings of the burning rate with temperature and magnetic field for a range of core temperature. We conclude that magnetar photospheres are very unlikely to contain hydrogen. This motivates theoretical work on heavy element atmospheres that are needed to measure effective temperature from the observed thermal emission and constrains models of AXPs that rely on magnetar cooling through thick light element envelopes.

P. Chang; P. Arras; L. Bildsten

2004-10-18T23:59:59.000Z

453

Solar Magnetic Flux Ropes  

E-Print Network [OSTI]

The most probable initial magnetic configuration of a CME is a flux rope consisting of twisted field lines which fill the whole volume of a dark coronal cavity. The flux ropes can be in stable equilibrium in the coronal magnetic field for weeks and even months, but suddenly they loose their stability and erupt with high speed. Their transition to the unstable phase depends on the parameters of the flux rope (i.e., total electric current, twist, mass loading etc.), as well as on the properties of the ambient coronal magnetic field. One of the major governing factors is the vertical gradient of the coronal magnetic field which is estimated as decay index (n). Cold dense prominence material can be collected in the lower parts of the helical flux tubes. Filaments are therefore good tracers of the flux ropes in the corona, which become visible long before the beginning of the eruption. The perspectives of the filament eruptions and following CMEs can be estimated by the comparison of observed filament heights with...

Filippov, Boris; Srivastava, Abhishek K; Uddin, Wahab

2015-01-01T23:59:59.000Z

454

Complex Materials  

ScienceCinema (OSTI)

Valentino Cooper uses some of the world's most powerful computing to understand how materials work at subatomic levels, studying breakthroughs such as piezoelectrics, which convert mechanical stress to electrical energy.

Cooper, Valentino

2014-05-23T23:59:59.000Z

455

Complex Materials  

SciTech Connect (OSTI)

Valentino Cooper uses some of the world's most powerful computing to understand how materials work at subatomic levels, studying breakthroughs such as piezoelectrics, which convert mechanical stress to electrical energy.

Cooper, Valentino

2014-04-17T23:59:59.000Z

456

Material Symbols   

E-Print Network [OSTI]

What is the relation between the material, conventional symbol structures that we encounter in the spoken and written word, and human thought? A common assumption, that structures a wide variety of otherwise competing ...

Clark, Andy

2006-01-01T23:59:59.000Z

457

Materializing interaction  

E-Print Network [OSTI]

At the boundary between people, objects and spaces, we encounter a broad range of surfaces. Their properties perform functional roles such as permeability, comfort or illumination, while conveying information such as an ...

Coelho, Marcelo

2013-01-01T23:59:59.000Z

458

Depolarization of D-T plasmas by recycling in material walls  

SciTech Connect (OSTI)

The feasibility of using polarized deuterium (D) and tritium (T) plasmas in fusion reactors may be seriously affected by recycling in material walls. Theoretical and experimental results are reviewed which show how the depolarization rates of absorbed D and T depend on first wall parameters such as the temperature, the bulk and surface diffusivities, the density of electronic states at the Fermi surface, the spectral density of microscopic fluctuating electric field gradients, and the concentration of paramagnetic impurities. Nuclear magnetic resonance (NMR) spectroscopy of hydrogenated and deuterated amorphous semiconductors suggests that low-Z nonmetallic materials may provide a satisfactory first wall or limiter coating under reactor conditions with characteristic depolarization times of several seconds. Experiments are proposed to test the consequences of our analysis.

Greenside, H.S.; Budny, R.V.; Post, D.E.

1984-02-01T23:59:59.000Z

459

MECHATRONICS ASPECTS OF SMART MATERIALS INDUCED STRAIN ACTUATION Victor Giurgiutiu  

E-Print Network [OSTI]

1 MECHATRONICS ASPECTS OF SMART MATERIALS INDUCED STRAIN ACTUATION Victor Giurgiutiu University-777-0106, email victorg@sc.edu Abstract: The mechatronics aspects of smart materials induced-strain actuation are investigated. Smart materials, a.k.a. active materials, are able to transform electric, magnetic, thermal

Giurgiutiu, Victor

460

SUPER HARD SURFACED POLYMERS  

SciTech Connect (OSTI)

High energy ion beam surface treatments were applied to a selected group of polymers. Of the six materials in the present study, four were thermoplastics (polycarbonate, polyethylene, polyethylene terephthalate, and polystyrene) and two were thermosets (epoxy and polyimide). The particular epoxy evaluated in this work is one of the resins used in formulating fiber reinforced composites for military helicopter blades. Measures of mechanical properties of the near surface regions were obtained by nanoindentation hardness and pin on disk wear. Attempts were also made to measure erosion resistance by particle impact. All materials were hardness tested. Pristine materials were very soft, having values in the range of approximately 0.1 to 0.5 GPa. Io