Powered by Deep Web Technologies
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

Magnetic Materials  

Science Conference Proceedings (OSTI)

Oct 27, 2009 ... Extreme magnetic fields (>2 tesla), especially when combined with temperature, are being shown to revolutionize materials processing and...

2

System and method for non-destructive evaluation of surface characteristics of a magnetic material  

DOE Patents (OSTI)

A system and a related method for non-destructive evaluation of the surface characteristics of a magnetic material. The sample is excited by an alternating magnetic field. The field frequency, amplitude and offset are controlled according to a predetermined protocol. The Barkhausen response of the sample is detected for the various fields and offsets and is analyzed. The system produces information relating to the frequency content, the amplitude content, the average or RMS energy content, as well as count rate information, for each of the Barkhausen responses at each of the excitation levels applied during the protocol. That information provides a contiguous body of data, heretofore unavailable, which can be analyzed to deduce information about the surface characteristics of the material at various depths below the surface.

Jiles, David C. (Ames, IA); Sipahi, Levent B. (Ames, IA)

1994-05-17T23:59:59.000Z

3

Magnetic Materials Staff  

Science Conference Proceedings (OSTI)

... Materials Science and Engineering Division Staff Directory; MML Organization. Contact. Magnetic Materials Group Robert Shull, Group Leader. ...

2012-10-09T23:59:59.000Z

4

Permanent Magnet Materials  

Science Conference Proceedings (OSTI)

Table 4   Applications of permanent magnet materials...material Primary reason for selection Alternative material Condition or reason favoring selection of alternative material Aircraft magnetos, military or civilian SmCo Maximum energy per unit volume Cast Alnico 5 Availability or cost restraint Alternators SmCo Compactness and reliability Ferrite...

5

Permanent Magnet Materials  

Science Conference Proceedings (OSTI)

Table 4 Applications of permanent magnet materials...material Primary reason for selection Alternative material Condition or reason favoring selection of alternative material Aircraft magnetos, military or civilian SmCo Maximum energy per unit volume Cast Alnico 5 Availability or cost restraint Alternators SmCo Compactness and reliability Ferrite...

6

Large Magnetization at Carbon Surfaces  

NLE Websites -- All DOE Office Websites (Extended Search)

Large Magnetization at Carbon 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 element. Now, another use has been found: magnets. One would not expect pure carbon to be magnetic, but for more than ten years scientists have suspected that carbon can be made to be magnetic by doping it with nonmagnetic materials, changing its order ever so slightly. Years ago, the first x-ray images obtained using the scanning transmission x-ray microscope at ALS Beamline 11.0.2 provided valuable insight into how proton irradiation can cause carbon to transform into a ferromagnetic material. Now, researchers are using x-ray spectroscopy at ALS Beamline 4.0.2 to study the magnetism of proton-irradiated graphite surfaces in order to understand the effects of hydrogen (i.e. protons) on the electronic structure of carbon. In studying the properties of electrons responsible for magnetic order in graphite, researchers found that a very large magnetic moment is essentially switched on when hydrogen atoms are incorporated at the surface of graphite.

7

Large Magnetization at Carbon Surfaces  

NLE Websites -- All DOE Office Websites (Extended Search)

Large Magnetization at Carbon Surfaces Print Large Magnetization at Carbon Surfaces Print From organic matter to pencil lead, carbon is a versatile element. Now, another use has been found: magnets. One would not expect pure carbon to be magnetic, but for more than ten years scientists have suspected that carbon can be made to be magnetic by doping it with nonmagnetic materials, changing its order ever so slightly. Years ago, the first x-ray images obtained using the scanning transmission x-ray microscope at ALS Beamline 11.0.2 provided valuable insight into how proton irradiation can cause carbon to transform into a ferromagnetic material. Now, researchers are using x-ray spectroscopy at ALS Beamline 4.0.2 to study the magnetism of proton-irradiated graphite surfaces in order to understand the effects of hydrogen (i.e. protons) on the electronic structure of carbon. In studying the properties of electrons responsible for magnetic order in graphite, researchers found that a very large magnetic moment is essentially switched on when hydrogen atoms are incorporated at the surface of graphite.

8

Large Magnetization at Carbon Surfaces  

NLE Websites -- All DOE Office Websites (Extended Search)

Large Magnetization at Carbon Surfaces Print Large Magnetization at Carbon Surfaces Print From organic matter to pencil lead, carbon is a versatile element. Now, another use has been found: magnets. One would not expect pure carbon to be magnetic, but for more than ten years scientists have suspected that carbon can be made to be magnetic by doping it with nonmagnetic materials, changing its order ever so slightly. Years ago, the first x-ray images obtained using the scanning transmission x-ray microscope at ALS Beamline 11.0.2 provided valuable insight into how proton irradiation can cause carbon to transform into a ferromagnetic material. Now, researchers are using x-ray spectroscopy at ALS Beamline 4.0.2 to study the magnetism of proton-irradiated graphite surfaces in order to understand the effects of hydrogen (i.e. protons) on the electronic structure of carbon. In studying the properties of electrons responsible for magnetic order in graphite, researchers found that a very large magnetic moment is essentially switched on when hydrogen atoms are incorporated at the surface of graphite.

9

Large Magnetization at Carbon Surfaces  

NLE Websites -- All DOE Office Websites (Extended Search)

Large Magnetization at Carbon Surfaces Print Large Magnetization at Carbon Surfaces Print From organic matter to pencil lead, carbon is a versatile element. Now, another use has been found: magnets. One would not expect pure carbon to be magnetic, but for more than ten years scientists have suspected that carbon can be made to be magnetic by doping it with nonmagnetic materials, changing its order ever so slightly. Years ago, the first x-ray images obtained using the scanning transmission x-ray microscope at ALS Beamline 11.0.2 provided valuable insight into how proton irradiation can cause carbon to transform into a ferromagnetic material. Now, researchers are using x-ray spectroscopy at ALS Beamline 4.0.2 to study the magnetism of proton-irradiated graphite surfaces in order to understand the effects of hydrogen (i.e. protons) on the electronic structure of carbon. In studying the properties of electrons responsible for magnetic order in graphite, researchers found that a very large magnetic moment is essentially switched on when hydrogen atoms are incorporated at the surface of graphite.

10

Large Magnetization at Carbon Surfaces  

NLE Websites -- All DOE Office Websites (Extended Search)

Large Magnetization at Carbon Surfaces Print Large Magnetization at Carbon Surfaces Print From organic matter to pencil lead, carbon is a versatile element. Now, another use has been found: magnets. One would not expect pure carbon to be magnetic, but for more than ten years scientists have suspected that carbon can be made to be magnetic by doping it with nonmagnetic materials, changing its order ever so slightly. Years ago, the first x-ray images obtained using the scanning transmission x-ray microscope at ALS Beamline 11.0.2 provided valuable insight into how proton irradiation can cause carbon to transform into a ferromagnetic material. Now, researchers are using x-ray spectroscopy at ALS Beamline 4.0.2 to study the magnetism of proton-irradiated graphite surfaces in order to understand the effects of hydrogen (i.e. protons) on the electronic structure of carbon. In studying the properties of electrons responsible for magnetic order in graphite, researchers found that a very large magnetic moment is essentially switched on when hydrogen atoms are incorporated at the surface of graphite.

11

Electronic, Magnetic & Photonic Materials Division  

Science Conference Proceedings (OSTI)

... Committee Energy Conversion and Storage Committee Magnetic Materials Committee Nanomaterials Committee Thin Films and Interfaces Committee.

12

Bespoke Materials Surfaces  

NLE Websites -- All DOE Office Websites (Extended Search)

Bespoke Materials Surfaces Bespoke Materials Surfaces Background The Department of Energy (DOE) has established performance and efficiency goals for power generation systems which will improve the ability of the U.S. energy sector to produce electricity efficiently with less impact to the environment. Power systems showing the most promise for reaching these goals require corrosion resistance alloys able to perform at very high pressures and temperatures. Increasing both the

13

Magnetic Materials Group Homepage  

Science Conference Proceedings (OSTI)

... and simulation to become the driving force in ... develop a real-time magnetic domain imaging ... data-storage and permanent magnets with increased ...

2012-12-03T23:59:59.000Z

14

Magnetic Materials for Green Innovation  

Science Conference Proceedings (OSTI)

... Magnetic Materials for Use in Energy-efficient Distribution Transformers ... Novel Morphology of Highly Efficient Two-phase Ferrite Cores for Power Systems

15

Requirements of Magnetic Materials for Current Technological ...  

Science Conference Proceedings (OSTI)

Mar 3, 2011 ... Magnetic Materials for Energy Applications: Requirements of Magnetic ... Hard magnetic materials play a significant role in many green...

16

Nanostructrured Magnetic Materials  

Science Conference Proceedings (OSTI)

Aug 8, 2013 ... The demand for OFF-ON becomes increasingly important as ... The residual magnetic flux density and maximum energy product of the...

17

Magnetic Materials and Properties  

Science Conference Proceedings (OSTI)

Aug 5, 2013 ... Following vacuum distillation of the Mg-RE alloy, 98% pure RE metals can be recovered, which are then used to synthesize permanent magnet...

18

Final Technical Progress Report NANOSTRUCTURED MAGNETIC MATERIALS  

SciTech Connect

This report describes progress made during the final phase of our DOE-funded program on Nanostructured Magnetic Materials. This period was quite productive, resulting in the submission of three papers and presentation of three talks at international conferences and three seminars at research institutions. Our DOE-funded research efforts were directed toward studies of magnetism at surfaces and interfaces in high-quality, well-characterized materials prepared by Molecular Beam Epitaxy (MBE) and sputtering. We have an exceptionally well-equipped laboratory for these studies, with: Thin film preparation equipment; Characterization equipment; Equipment to study magnetic properties of surfaces and ultra-thin magnetic films and interfaces in multi-layers and superlattices.

Charles M. Falco

2012-09-13T23:59:59.000Z

19

Surface Protection for Enhanced Materials Performance: Science ...  

Science Conference Proceedings (OSTI)

About this Symposium. Meeting, Materials Science & Technology 2013. Symposium, Surface Protection for Enhanced Materials Performance: Science,...

20

Electronic, Magnetic & Photonic Materials Division Council - TMS  

Science Conference Proceedings (OSTI)

Welcome to the Electronic, Magnetic, and Photonic Materials Division (EMPMD) which is composed of fourteen technical and administrative committees. TMS...

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

Fabrication of Nanocrystalline Magnetic Materials for use in Energy ...  

Science Conference Proceedings (OSTI)

Symposium, Magnetic Materials for Energy Applications IV ... magnetic softness, resulting in limited saturation magnetization, Bs. Chemical optimization, thus,...

22

Nanostructured Materials for Magnetic Refrigeration  

Science Conference Proceedings (OSTI)

... of Nd-Fe-B Magnets to the Megawatt Scale Generator for the Wind Turbine ... Low Loss, High Power Density Magnetics in Inductor/Transformer Cores for Army ...

23

Fe and Mn based materials for magnetic refrigeration  

Science Conference Proceedings (OSTI)

Symposium, Magnetic Materials for Energy Applications IV ... NANO- CRYSTALLINE SOFT MAGNETIC ALLOYS CONTRIBUTABLE TO ENERGY- SAVING.

24

Magnetic Materials for Energy Applications IV  

Science Conference Proceedings (OSTI)

Energy efficient cooling based on the magnetocaloric effect is an exciting possibility which is rapidly becoming ... Magnetic Materials for Green Innovation.

25

Magnetism in Non-Traditional Materials  

SciTech Connect

We performed a systematic microscopic investigation of two completely dissimilar materials (namely, ZnO and rhombohedral-C{sub 60} polymers) exhibiting ferromagnetism in the presence of defects, and showed that this new phenomena has a common origin and the mechanism responsible can be used as a powerful tool for inducing and tailoring magnetic features in systems which are not magnetic otherwise. Based on our findings we proposed a general recipe for developing ferromagnetism in new materials of great technological interest. Our results support the role of complimentary pairs of defects in inducing magnetism in otherwise non-magnetic materials belonging to two widely differing classes with no apparent correlation between them. In both classes, ferromagnetism is found to be enhanced when the two kinds of defects form structures (pathways) of alternating effective donor and acceptor crystal sites leading to the development of electron charge and spin density like waves. Using ab initio density functional theory calculations we predicted the existence of a new class of carbon cages formed via hybrid connection between planar graphene sheets and carbon nanotubes. The resulting novel structure has the appearance of ?nano-drum? and offers the exciting prospect of integrating useful device properties of both graphene as well as the nanotube into a single unit with tunable electronic properties. Creation of a hexagonal hole in the graphene portion of this structure results in significant magnetic moments for the edge atoms. The structure appears to be capable of sustaining ferrimagnetic state with the assistance of topological defects. The charge and spin distributions obtained in our calculations for the nano-drums are in striking contrast to those in planar graphene nanoribbons with a central hole. In this case, the central hole appears as the complimentary defect to those of the ribbon edges. Similar situation is found in case of the nano-drum in which the complimentary to the hole defects appear to be the pentagons along the curved surface of the drum. Charge oscillations found in the nano-drum are minimized in the nanoribbons. But more importantly, the hole edge atoms in the nano-drums retain significant magnetic moments; almost twice those of the corresponding ones in hydrogenated graphene nanoribbons (H-GNRs). These results suggest that the topological defects in the nano-drums may act like blocks to keep magnetic moments from ?leaking? out from the hole defects. This may have significant implications for the the use of nano-drums in magnetic storage technology where the ratio, magnetic-moment/weight, is of paramount importance in any futuristic device applications. One of the basic problems of the DFT/LSDA+U theory is the efficient evaluation of the U-term. With this in mind we proposed an alternative approach for its calculation which is based on the knowledge of the Hartree-Fock wave functions of the system under consideration. As a result, the proposed approach is closer to the basic definition of the DFT/LSDA+U scheme and its hybrid-DFT nature. According to our approach, the U value is obtained in a consistent and ab-initio way using the self-consistently calculated wave functions of the given system at the level of the HF approximation. Our method is applicable for systems which include more than one type of elements with localized d-orbitals. The method has been applied the case of the doped Zn(Co)O systems successfully. Currently, theories based on conventional superexchange or double-exchange interactions cannot explain long range magnetic order at concentrations below percolation threshold in dilute magnetic semiconductors. On the other hand, the codoping induced magnetism, which can justify magnetic interactions below percolation threshold, has eluded explanation. With this in mind, we proposed that defect-induced magnetism in codoped non-magnetic materials can be viewed within a molecular generalization of the atomic double-exchange and superexchange interactions applied to an arbitrary bipartite lattice host

Menon, Madhu

2013-09-17T23:59:59.000Z

26

The Search for Enhanced Magnetic Materials - Programmaster.org  

Science Conference Proceedings (OSTI)

Symposium, Magnetic Materials for Energy Applications -III. Presentation Title, The ... Advances in Rare-earth Free Permanent Magnets Anisotropic Curie...

27

Crystallographic Boundary in a Magnetic Shape Memory Material  

NLE Websites -- All DOE Office Websites (Extended Search)

Home Science Highlights Science Briefs Crystallographic Boundary in a Magnetic Shape Memory Material Crystallographic Boundary in a Magnetic Shape Memory Material Print...

28

Theory, Design and Development of Artificial Magnetic Materials.  

E-Print Network (OSTI)

??Artificial Magnetic Materials (AMMs) are a subgroup of metamaterials which are engineered to provide desirable magnetic properties not seen in natural materials. These artificial structures (more)

Yousefi, Leila

2009-01-01T23:59:59.000Z

29

Analysis of Soft Magnetic Materials for Energy Applications  

Science Conference Proceedings (OSTI)

Presentation Title, Analysis of Soft Magnetic Materials for Energy Applications ... Abstract Scope, The world-wide market for magnetic materials is anticipated to...

30

Magnetic spectroscopy and microscopy of functional materials  

SciTech Connect

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

31

Magnetic instabilities in accelerating plasma surfaces  

SciTech Connect

The existence of an interchange instability strictly associated with electron inertia is demonstrated. This is characterized by a growth rate significantly larger than the usual ion-inertial Rayleigh-Taylor rate and by self-generated magnetic fields localized around the accelerating plasma surface. This novel instability may be partially responsible for the observed magnetic fields in ablatively accelerated laser plasmas.

Amendt, P.; Rahman, H.U.; Strauss, M.

1984-09-24T23:59:59.000Z

32

Large Magnetization at Carbon Surfaces  

NLE Websites -- All DOE Office Websites (Extended Search)

switched on when hydrogen atoms are incorporated at the surface of graphite. Doping Graphene Graphene has attracted a lot of interest since researchers found an easy way to...

33

Critical Magnetic Field Determination of Superconducting Materials  

Science Conference Proceedings (OSTI)

Superconducting RF technology is becoming more and more important. With some recent cavity test results showing close to or even higher than the critical magnetic field of 170-180 mT that had been considered a limit, it is very important to develop a way to correctly measure the critical magnetic field (H{sup RF}{sub c}) of superconductors in the RF regime. Using a 11.4 GHz, 50-MW, electric field at the sample surface. A model of the system is presented in this paper along with a discussion of preliminary experimental data.

Canabal, A.; Tajima, T.; /Los Alamos; Dolgashev, V.A.; Tantawi, S.G.; /SLAC; Yamamoto, T.; /Tsukuba, Natl. Res. Lab. Metrol.

2011-11-04T23:59:59.000Z

34

Magnetic mesoporous materials for removal of environmental wastes  

Science Conference Proceedings (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

35

Large Magnetization at Carbon Surfaces  

NLE Websites -- All DOE Office Websites (Extended Search)

x-ray microscope at ALS Beamline 11.0.2 provided valuable insight into how proton irradiation can cause carbon to transform into a ferromagnetic material. Now, researchers are...

36

Anomalous magnetic moment of an electron near a dispersive surface  

E-Print Network (OSTI)

Changes in the magnetic moment of an electron near a dielectric or conducting surface due to boundary-dependent radiative corrections are investigated. The electromagnetic field is quantized by normal mode expansion for a non-dispersive dielectric and an undamped plasma, but the electron is described by the Dirac equation without matter-field quantization. Perturbation theory in the Dirac equation leads to a general formula for the magnetic moment shift in terms of integrals over products of electromagnetic mode functions. In each of the models investigated contour integration techniques over a complex wave vector can be used to derive a general formula featuring just integrals over transverse electric and transverse magnetic reflection coefficients of the surface. Analysis of the magnetic moment shift for several classes of materials yields markedly different results from the previously considered simplistic 'perfect reflector' model, due to the inclusion of physically important features of the electromagnetic response of the surface such as evanescent field modes and dispersion in the material. For a general dispersive dielectric surface, the magnetic moment shift of a nearby electron can exceed the previous prediction of the perfect-reflector model by several orders of magnitude.

Robert Bennett; Claudia Eberlein

2013-04-04T23:59:59.000Z

37

Magnetic Materials for Broadband Transmission Line  

E-Print Network (OSTI)

The authors series of articles on broadband transmission line transformers (TLTs) concludes with these notes on magnetic materials and the properties that are important for best performance Ferrite and iron powder magnetic materials were developed to support a wide range of components, including inductors, EMI suppressors, conventional transformers and transmission line transformers (TLTs). This article deals with transmission line transformers, presenting the observations and conclusions of the author, reached after extensive experimental research into the behavior and performance of these devices in broadband applications. Figure 1 The three transformers used in comparing the performance of the autotransformer and the transmission line transformer. At the top left is an autotransformer; at the top right is the transmission line transformer, while at the bottom is a transmission line transformer without a ferrite core. All transformers had a total of 10 turns.

Jerry Sevick

2005-01-01T23:59:59.000Z

38

Magnetic surfaces in an axisymmetric torus  

SciTech Connect

A method is developed for specifying the boundary equilibrium magnetic surface in an axially symmetric torus by using the absolute values of the magnetic field B = B{sub s}({theta}) and the gradient of the poloidal flux vertical bar vertical bar {nabla}{Psi} vertical bar = vertical bar {nabla}{Psi} vertical bar {sub s}({theta}) in a special flux coordinate system. By setting two surface constants (e.g., the safety factor q and dp/d{Psi}) and matching the absolute values of the magnetic field and the flux gradient on a closed magnetic surface, it is possible to find all equilibrium magnetic functions (including n {center_dot} {nabla} ln B and the local shear s) and all constants (including the toroidal current J and the shear d{mu}/d{Psi}) on this surface. Such a non-traditional formulation of the boundary conditions in solving the stability problem in an axisymmetric torus allows one to impose intentional conditions on plasma confinement and MHD stability at the periphery of the system.

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

2013-04-15T23:59:59.000Z

39

Industrial Needs and Applications for Soft Magnetic Materials  

Science Conference Proceedings (OSTI)

Presentation Title, Industrial Needs and Applications for Soft Magnetic Materials. Author(s) ... Bonded Magnetocaloric Powders for the Refrigeration Application.

40

Industrial Requirements and Applications of Hard Magnetic Materials  

Science Conference Proceedings (OSTI)

Presentation Title, Industrial Requirements and Applications of Hard Magnetic Materials ... Bonded Magnetocaloric Powders for the Refrigeration Application.

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

The Requirements of Soft Magnetic Materials for Industrial ...  

Science Conference Proceedings (OSTI)

Advanced electric machines and drives, often with permanent magnet architectures, are being developed to ... Materials for Motors of Hybrid Automobiles.

42

Production of Materials with Superior Properties Utilizing High Magnetic Field  

Processing materials in a magnetic field is an innovative and revolutionary means to change materials and structural properties by tailoring the ...

43

REACT: Alternatives to Critical Materials in Magnets  

Science Conference Proceedings (OSTI)

REACT Project: The 14 projects that comprise ARPA-Es 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

44

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.

Komvopoulos, Kyriakos (Orinda, CA); Brown, Ian G. (Berkeley, CA); Wei, Bo (Albany, CA); Anders, Simone (Albany, CA); Anders, Andre (Albany, CA); Bhatia, Singh C. (Morgan Hill, CA)

1995-01-01T23:59:59.000Z

45

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

46

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

SciTech Connect

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.

2013-10-08T23:59:59.000Z

47

Material's Properties Control by Nano-Scale Surface Functionalization...  

NLE Websites -- All DOE Office Websites (Extended Search)

Material's Properties Control by Nano-Scale Surface Functionalization Material's Properties Control by Nano-Scale Surface Functionalization Theme We aim at developing an original...

48

Soft Magnetic Materials Fabricated by Rapid Quenching Technique ...  

Science Conference Proceedings (OSTI)

Symposium, Magnetic Materials for Energy Applications. Presentation Title ... Current Status of Permanent Magnet Research and Market in China ... First to Second Order Magnetocaloric Transition: on Correct Analysis of Experimental Data.

49

1. electronic,magnetic & photonic materials division bylaws  

Science Conference Proceedings (OSTI)

ELECTRONIC, MAGNETIC & PHOTONIC MATERIALS DIVISION. BYLAWS. Revisions 3/12/12. ARTICLE I. Name and Objective. Section 1. The name of the...

50

Overcoming a Magnetic Sticking Point - Materials Technology @ TMS  

Science Conference Proceedings (OSTI)

Aug 25, 2009... magnetic effects into a new functional form that could be useful for integration with unconventional materials, according to the researchers.

51

Introduction To Magnetic Materials, Second Edition - TMS  

Science Conference Proceedings (OSTI)

Oct 1, 2009... amorphous alloys or metallic glasses used in cores of transformers, generators , motors, inductors, microwave components) and magnetically...

52

LANL: Facility Focus, MST-6 Materials Surface Science Investigations Laboratory  

NLE Websites -- All DOE Office Websites (Extended Search)

07-018 Spring 2007 07-018 Spring 2007 T he MST-6 Materials Surface Science Investigations Laboratory is home to a one-of-a-kind integrated instrument for surface science and materials research, allowing scientists at Los Alamos National Laboratory the unique opportunity to perform coordinated research using ultra-high vacuum surface measurements, in situ reactions, and materials synthesis tools. Housed in the Materials Science Laboratory, the surface science instrument features an ultra-clean integrated system for surface analysis and in situ surface modification, thin film deposition, and surface gas reactions. This integrated system is used for analytical surface science; materials electronic

53

Role of Magnetic Fields and Texturing to Improved Magnetic Materials  

Science Conference Proceedings (OSTI)

Mar 13, 2012 ... Experiments to observe the structural and magnetic phase transformations were performed at the Spallation Neutron Source (SNS) at Oak...

54

H. Rare Earth, Electronic, and Magnetic Materials  

Science Conference Proceedings (OSTI)

... Nd-Fe-B Permanent Magnets Unique Exchange Bias Induced by Antiferromagnetic Cr-oxide ZnO-graphene Hybrid Quantum Dots Light Emitting Diode...

55

Magnetic Materials for Energy Applications -III  

Science Conference Proceedings (OSTI)

TMS: Energy Committee TMS: Energy Conversion and Storage Committee ... Optimization of the Mechanical Alloying Process of Soft Magnetic Fe-Based...

56

Soft Magnetic Materials in Energy Applications  

Science Conference Proceedings (OSTI)

Current Status of Permanent Magnet Research and Market in China ... First to Second Order Magnetocaloric Transition: on Correct Analysis of Experimental...

57

Surface Induced Magnetism in Quantum Dots  

SciTech Connect

The study of nanometer sized semiconductor crystallites, also known as quantum dots (QDs), has seen rapid advancements in recent years in scientific disciplines ranging from chemistry, physics, biology, materials science, and engineering. QD materials of CdSe, ZnSe, InP, as well as many others, can be prepared in the size range of 1-10 nm producing uniform, nearly monodisperse materials that are typically coated with organic molecules [1-3]. The strength of charge carrier confinement, which dictates the size-dependent properties, in these QDs depends on the nature of the material and can be correlated to the Bohr radius for the system of interest. For instance, the Bohr radius for CdSe is {approx} 5 nm, while in the more covalent structure of InP, the Bohr radius approaches {approx} 10 nm. The study of CdSe QDs has been particularly extensive during the last decade because they exhibit unique and tunable optical properties and are readily synthesized with high-crystallinity and narrow size dispersions. Although the core electronic properties of CdSe are explained in terms of the quantum confinement model, experimental efforts to elucidate the surface structure of these materials have been limited. Typically, colloidal CdSe QDs are coated with an organic surfactant, which typically consists of an organo-phosphine, -thiol, or -amine, that has the function of energetically relaxing defect states via coordination to partially coordinated surface atoms. The organic surfactant also acts to enhance carrier confinement and prevent agglomeration of the particles. Chemically, it has been shown that the bonding of the surfactant to the CdSe QD occurs through Cd atoms resulting cleavage of the Se atoms and formation of a Cd-rich (i.e. non-stoichiometric) particle [5].

Meulenberg, R W; Lee, J I

2009-08-20T23:59:59.000Z

58

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

59

Power Magnetic Materials - Programmaster.org  

Science Conference Proceedings (OSTI)

Symposium, Advanced Materials for Power Electronics, Power Conditioning, and ... away from low frequency transformers to modular power electronic systems...

60

General Abstracts: Electronic, Magnetic, and Photonic Materials ...  

Science Conference Proceedings (OSTI)

May 1, 2007... of Nanocrystalline Structure in Metals by Severe Plastic Deformation ... electronic packaging and inter-connection materials, nanomaterials,...

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

Magnetic Materials for High Frequency Power Electronics  

Science Conference Proceedings (OSTI)

Mar 7, 2013 ... Advanced Materials for Power Electronics, Power Conditioning, and Power ... in power conditioning, conversion, and generation applications.

62

Method for making mirrored surfaces comprising superconducting material  

DOE Patents (OSTI)

Superconducting mirror surfaces are provided by forming a mirror surface from a material which is superconductive at a temperature above about 40 K and adjusting the temperature of the surface to that temperature at which the material is superconducting. The mirror surfaces are essentially perfect reflectors for electromagnetic radiation with photon energy less than the superconducting band gap.

Early, J.T.; Hargrove, R.S.

1989-12-12T23:59:59.000Z

63

Argonne CNM: Electronic and Magnetic Materials and Devices Research  

NLE Websites -- All DOE Office Websites (Extended Search)

Electronic & Magnetic Materials & Devices Electronic & Magnetic Materials & Devices Group Leader: Saw-Wai Hla The objective of the Electronic and Magnetic Materials and Devices (EMMD) group at the CNM is to discover, understand, and utilize new electron and spin-based materials and phenomena in constrained geometries. Potential benefits include reduced power dissipation, new medical imaging methods and therapies, improved efficiency of data storage by spin current and electrical field-assisted writing, and enhanced energy conversion in photovoltaic devices. Research Activities Understanding complex magnetic order and coupling phenomena: Magnetic nanostructures are prone to complex magnetic ordering phenomena that do not occur in the bulk and that will have strong impact on the further development of functional magnetic nanostructures. Basic science on the influence of demagnetizing effects, geometrical frustration, next-nearest neighbor exchange interactions, unusual anisotropy values, and the spin-orbit interaction at reduced dimensionality are performed with a special focus on temperature-dependent magnetic order-disorder transitions.

64

Solidification Processing of Materials in Magnetic Fields  

Science Conference Proceedings (OSTI)

7. S. Asai, Metallurgical Aspects of Electromagnetic Processing of Materials in Liquid Metal Magnetohydrodynamics, ed. J. Lielpeteris and R. Moreau (Boston,...

65

Method for removing oil-based materials from water surface  

SciTech Connect

A method is described for removing oil-based materials floating on the surface of ballast water contained in the ballast tank of a cargo carrier having vertical steel surfaces. The method consists of adding to said surface a spreading agent having a spreading force greater than the oil-based material in an amount sufficient to force substantially all of the material against the surfaces. The ballast water is discharged from the tank at a point below the surface of the water, the oil-based material is forced to deposit on the steel surfaces vacated by the discharged water.

Shewmaker, J.E.

1981-10-06T23:59:59.000Z

66

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.

Richter, Tomas (State College, PA)

1998-01-01T23:59:59.000Z

67

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

68

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

SciTech Connect

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

69

End station for nanoscale magnetic materials study: Combination of scanning tunneling microscopy and soft X-ray magnetic circular dichroism spectroscopy  

SciTech Connect

We have constructed an end station for nanoscale magnetic materials study at the soft X-ray beamline HiSOR BL-14 at Hiroshima Synchrotron Radiation Center. An ultrahigh-vacuum scanning tunneling microscope (STM) was installed for an in situ characterization of nanoscale magnetic materials in combination with soft X-ray magnetic circular dichroism (XMCD) spectroscopy experiment. The STM was connected to the XMCD experimental station via damper bellows to isolate it from environmental vibrations, thus achieving efficient spatial resolution for observing Si(111) surface at atomic resolution. We performed an in situ experiment with STM and XMCD spectroscopy on Co nanoclusters on an Au(111) surface and explored its practical application to investigate magnetic properties for well-characterized nanoscale magnetic materials.

Ueno, Tetsuro; Sawada, Masahiro; Namatame, Hirofumi [Hiroshima Synchrotron Radiation Center, Hiroshima University, 2-313 Kagamiyama, Higashi-Hiroshima 739-0046 (Japan); Kishimizu, Yusuke; Kimura, Akio [Graduate School of Science, Hiroshima University, 1-3-1 Kagamiyama, Higashi-Hiroshima 739-8526 (Japan); Taniguchi, Masaki [Hiroshima Synchrotron Radiation Center, Hiroshima University, 2-313 Kagamiyama, Higashi-Hiroshima 739-0046 (Japan); Graduate School of Science, Hiroshima University, 1-3-1 Kagamiyama, Higashi-Hiroshima 739-8526 (Japan)

2012-12-15T23:59:59.000Z

70

DistributionCategory: Magnetic Fusion Reactor Materials  

E-Print Network (OSTI)

that its use would not infringe privately owned rights. Reference herein to any specific commercial product. Several analyses of this vapor shielding effect have been performed [l-71.Some previouswork focused on one function q (Z,t) is calculated, in the condensed target material, with detailed models that include

Harilal, S. S.

71

Crystallographic Boundary in a Magnetic Shape Memory Material  

NLE Websites -- All DOE Office Websites (Extended Search)

Crystallographic Boundary in a Crystallographic Boundary in a Magnetic Shape Memory Material Crystallographic Boundary in a Magnetic Shape Memory Material Print Wednesday, 18 April 2012 11:37 A research team has shown the existence of a special structural boundary in an intermetallic compound by combining the unique measurement facilities at the ALS, the single-crystal production capabilities of Tohoku University (Japan), and the materials science expertise of Johannes-Gutenberg-University (Germany). Conventional shape memory materials, such as the commercially available Nitinol (an alloy of nickel and titanium used in microsensing, actuation, and medical devices), undergo a phase transformation with cooling or heating when large areas of a sample distort along a single axis, and where the atomic-unit cell "stretching" from a cube to a rectangular prism occurs. In contrast, magnetic shape memory (MSM) materials are much more rare but have an advantage: The axis of magnetic anisotropy is coupled to the direction of stretching, so a perfect MSM crystal can be made to flex and bend reversibly by applying an external magnetic field.

72

TANK FARM INTERIM SURFACE BARRIER MATERIALS AND RUNOFF ALTERNATIVES STUDY  

SciTech Connect

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

73

Surfaces and Interfaces in Nanostructured Materials II  

Science Conference Proceedings (OSTI)

Nano-Structured Metals and Oxides. N-Implantation ... Nano-Scale Coatings for Surface Modification of Carbon Structures...........................................89. P.P. Joshi...

74

Surfaces and Interfaces in Nanostructured Materials - TMS  

Science Conference Proceedings (OSTI)

Mar 1, 2004 ... Proceedings from the Global Innovations Symposium on Materials ... by the MPMD, provide description, insight, challenges, and projections for...

75

Materials Physics Applications: The National High Magnetic Field Laboratory  

NLE Websites -- All DOE Office Websites (Extended Search)

Search Search National High Magnetic Field Laboratory, NHMFL Home About Us Organization DIVISION Materials Physics and Applications Division GROUPS Superconductivity Technology Center Condensed Matter and Magnet Science Center for Integrated Nanotechnologies Sensors & Electrochemical Devices Materials Chemistry CONTACTS Group Leader Mike Hundley Director, NHMFL-PFF/Deputy Group Leader Chuck Mielke Head of Users Program Operations Jon Betts Professional Staff Assistant Julie T. Gallegos TA-03 Group Office TA-03, Building 0034, Room 101 Office Administrator Juanita Armijo TA-35 Group Office TA-35, Building 0127, Room C117 Office Administrator Angeline Willow 505-667-5032 National High Magnetic Field Laboratory, Pulsed Field Facility The Pulsed Field Facility at Los Alamos National Laboratory in Los Alamos, New Mexico, is one of three campuses of the National High Magnetic Field Laboratory (NHMFL), the other two being at Florida State University, Tallahassee (continuous fields, magnetic resonance, and general headquarters) and the University of Florida ,Gainesville(ultra-low temperatures at high magnetic fields). The NHMFL is sponsored primarily by the National Science Foundation, Division of Materials Research, with additional support from the State of Florida and the US Department of Energy.

76

Bespoke Materials Surfaces Advanced Materials for Fireside Fossil Energy Applications  

E-Print Network (OSTI)

As the temperatures and pressures at which components in coal-fired boilers operate are increased, the materials capable of causing deposition of corrosive salts or erosion. In the furnace zone of coal-fired boilers conductivity, and that are tailored for easy application to the waterwall tubes of coal-fired boilers

77

Reference material RM 7811-7 for identification cards with high coercivity high density magnetic stripes  

E-Print Network (OSTI)

Reference material RM 7811-7 for identification cards with high coercivity high density magnetic stripes

Albrecht, M

2003-01-01T23:59:59.000Z

78

Magnetic Wall Climbing Robot for Thin Surfaces with Specific Obstacles  

E-Print Network (OSTI)

for inspecting the interior surfaces in gas tanks made out of thin metal sheets. These surfaces were inaccessible here was designed for inspecting gas tanks that are made out of thin metal sheets and are installed and mechanical calculations for robots on magnetic wheels. The chosen concept is described in detail, explaining

Paris-Sud XI, Université de

79

Design and fabrication of heat transfer surfaces from superplastic material  

Science Conference Proceedings (OSTI)

The production of complex heat transfer surfaces (i.e., those without straight fins) is restricted by available fabrication techniques, materials, geometries, and cost. Based on the superplastic sheet thermoforming process, a new technique for fabricating ...

J. B. Randolph; F. K. King

1972-05-01T23:59:59.000Z

80

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

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

Power Switches Utilizing Superconducting Material for Accelerator Magnets  

E-Print Network (OSTI)

Power switches that utilize superconducting material find application in superconducting systems. They can be used for the protection of magnets as a replacement for warm DC breakers, as well as for the replacement of cold diodes. This paper presents a comparison of switches made of various superconducting materials having transport currents of up to 600 A and switching times of the order of milliseconds. The switches operate in the temperature range 4.2-77 K and utilize stainless steel clad YBCO tape and MgB2 tape with a nickel, copper, and iron matrix. Results from simulations and tests are reported.

March, S A; Yang, Y; 10.1109/TASC.2009.2017890

2009-01-01T23:59:59.000Z

82

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

SciTech Connect

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

83

Dynamic high pressure process for fabricating superconducting and permanent magnetic materials  

DOE Patents (OSTI)

Shock waves directed on thin layers of materials is used to form superconducting and permanent magnetic materials with improved microstructures. 9 figs.

Nellis, W.J.; Maple, M.B.; Geballe, T.H.

1986-12-04T23:59:59.000Z

84

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

85

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

86

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

87

Non-principal surface waves in deformed incompressible materials  

E-Print Network (OSTI)

The Stroh formalism is applied to the analysis of infinitesimal surface wave propagation in a statically, finitely and homogeneously deformed isotropic half-space. The free surface is assumed to coincide with one of the principal planes of the primary strain, but a propagating surface wave is not restricted to a principal direction. A variant of Taziev's technique [Sov. Phys. Acoust. 35 (1989) 535] is used to obtain an explicit expression of the secular equation for the surface wave speed, which possesses no restrictions on the form of the strain energy function. Albeit powerful, this method does not produce a unique solution and additional checks are necessary. However, a class of materials is presented for which an exact secular equation for the surface wave speed can be formulated. This class includes the well-known Mooney-Rivlin model. The main results are illustrated with several numerical examples.

Michel Destrade; Melanie Ottenio; Alexey V. Pichugin; Graham A. Rogerson

2013-04-23T23:59:59.000Z

88

Argonne CNM: Electronic & Magnetic Materials & Devices Capabilities  

NLE Websites -- All DOE Office Websites (Extended Search)

Electronic & Magnetic Materials & Devices Capabilities Synthesis Colloidal chemistry and self-assembly techniques Complex oxide film synthesis via molecular beam epitaxy (DCA R450 Custom) Physical vapor deposition (Lesker CMS 18 and PVD 250) Spin coating (Laurell WS-400) Characterization Variable-temperature (VT) scanning tunneling microscope with atomic force microscopy capabilities (Omicron VT-AFM/STM), operates in an ultrahigh vacuum (UHV) environment with a base pressure of < 1E-10 mbar and 55-400 K. Atomic resolution is routinely obtained at room temperature and below. The AFM capabilities support a range of scanning modes. The analysis chamber also houses a LEED/Auger with an attached preparation chamber for sample cleaning and deposition (sputter cleaning, direct current heating, e-beam heating stage, metal deposition, etc.)

89

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

90

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

91

First-order Transition Magnetocaloric Materials in Rotary Magnetic ...  

Science Conference Proceedings (OSTI)

Abstract Scope, Astronautics has designed, constructed, and tested several ... requires accurate modeling of the magnetic refrigerator, accurate layering of a...

92

Enhancing Magnetic Properties of Molecular Magnetic Materials: The Role of Single-Ion Anisotropy  

E-Print Network (OSTI)

Considerable efforts are being devoted to designing enhanced molecular magnetic materials, in particular single molecule magnets (SMMs) that can meet the requirements for future technologies such as quantum computing and spintronics. A current trend in the field is enhancing the global anisotropy in metal complexes using single-ion anisotropy. The work in this dissertation is devoted to the synthesis and characterization of new building blocks of the highly anisotropic early transition metal ion V(III) with the aim of incorporating them into heterometallic molecular materials. The results underscore the importance of tuning the local coordination environments of metal ions in order to ensure enhanced single ion anisotropy. A family of mononuclear axially distorted vanadium (III) compounds, A[L_(3)VX_(3)] (3-9) (X = F, Cl or Br, A^(+) = Et_(4)N^(+), nBu_(4)N^(+) or PPN^(+) , L_(3) = Tp or Tp* (Tp = tris(-1-pyrazolyl)borohydride), Tp* = tris(3,5-dimethyl-1-pyrazolyl)borohydride)), and [Tp*V(DMF)_(3)](PF_(6))_(2) were studied. Replacement of the Tp ligand in 3 with the stronger ?-donor Tp* results in a near doubling of the magnitude of the axial zero-field splitting parameter D_(z) (D_(z) = -16.0 cm^(-1) in 3, and -30.0 cm^(-1) in 4) as determined by magnetic measurements. Such findings support the idea that controlling the axial crystal field distortion is an excellent way to enhance single-ion anisotropy. High Field-High Frequency EPR measurements on 4 revealed an even higher D value, -40.0 cm^(-1). Interestingly, compound 4 exhibits evidence for an out-of-phase ac signal under dc field. In another effort, a new series of vanadium cyanide building blocks, PPN[V(acac)_(2)(CN)_(2)]?PPNCl (13) (acac = acetylacetonate), A[V(L)(CN)_(2)] (A^(+) = Et_(4)N^(+), L = N,N'-Ethylenebis(salicylimine) (14), A = PPN^(+), L = N,N'-Ethylenebis(salicylimine) (15), L = N,N'-Phenylenebis(salicylimine) (16), and L = N,N'-Ethylenebis(2-methoxysalicylimine) (17)) were synthesized. Magnetic studies revealed moderate Dz values (-10.0, 5.89, 3.7, 4.05 and 4.36 cm^(-1) for 13-17 respectively). The first family of cyanide-bridged lanthanide containing molecules with a trigonal bipyramidal (TBP) geometry, (Et_(4)N)_(2)[(Re(triphos)(CN)_(3))_(2)(Ln(NO_(3))_(3))_(3)]-?4CH_(3)CN (19-27 with Ln = La, Ce, Pr, Nd, Sm, Gd, Tb, Dy and Ho) were prepared using the [(triphos)Re(CN)_(3)]^(-) building block, results that add valuable information to our database of compounds with a TBP geometry. Magnetic studies revealed diverse magnetic responses including slow relaxation of the magnetization at zero field for 25 and 26 , an indication of SMM behavior.

Saber, Mohamed Rashad Mohamed

2013-08-01T23:59:59.000Z

93

Method for producing high surface area chromia materials for catalysis  

SciTech Connect

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

94

Comparison of glass surfaces as a countertop material to existing surfaces  

SciTech Connect

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

95

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

96

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

97

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

Science Conference Proceedings (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 todays 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

98

Surface waves in a stretched and sheared incompressible elastic material  

E-Print Network (OSTI)

In this paper we analyze the effect of a combined pure homogeneous strain and simple shear in a principal plane of the latter on the propagation of surface waves for an incompressible isotropic elastic half-space whose boundary is normal to the glide planes of the shear. This generalizes previous work in which, separately, pure homogeneous strain and simple shear were considered. For a special class of materials the secular equation is obtained in explicit form and then specialized to recover results obtained previously for the two cases mentioned above. A method for obtaining the secular equation for a general form of strain-energy function is then outlined. In general this is very lengthy and the result is not listed, but, for the case in which there is no normal stress on the half-space boundary, the result is given, for illustration, in respect of the so-called generalized Varga material. Numerical results are given to show how the surface wave speed depends on both the underlying pure homogeneous strain and the superimposed simple shear. Further numerical results are provided for the Gent model of limiting chain extensibility.

Michel Destrade; Ray W. Ogden

2013-04-23T23:59:59.000Z

99

The Transformational Potential of Magnetic Materials: ARPA-E ...  

Science Conference Proceedings (OSTI)

The ARPA-E ADEPT program is focused on improvements in electrical energy efficiency ... Current Status of Permanent Magnet Research and Market in China.

100

Advanced Magnetic Materials for Next Generation Data Storage ...  

Science Conference Proceedings (OSTI)

All Solid State 2-Dimensional Li Battery Alloy Design and ... Rare-Earth Magnets Challenge to Development of Diamond Power Devices for Saving Energy.

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.


101

Implementation of solar-reflective surfaces: Materials and utility programs  

SciTech Connect

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

102

X-ray spectro-microscopy of complex materials and surfaces  

Science Conference Proceedings (OSTI)

The detailed understanding of complex materials used in information technology requires the use of state-of-the-art experimental techniques that provide information on the electronic and magnetic properties of the materials. The increasing miniaturization ...

J. Sthr; S. Anders

2000-07-01T23:59:59.000Z

103

A New Class of Magnetic Materials with Novel Structural Order | U.S. DOE  

NLE Websites -- All DOE Office Websites (Extended Search)

A New Class of Magnetic Materials with Novel Structural Order A New Class of Magnetic Materials with Novel Structural Order Basic Energy Sciences (BES) BES Home About Research Facilities Science Highlights Benefits of BES Funding Opportunities Basic Energy Sciences Advisory Committee (BESAC) News & Resources Contact Information Basic Energy Sciences U.S. Department of Energy SC-22/Germantown Building 1000 Independence Ave., SW Washington, DC 20585 P: (301) 903-3081 F: (301) 903-6594 E: sc.bes@science.doe.gov More Information » June 2013 A New Class of Magnetic Materials with Novel Structural Order The discovery of the first binary magnetic quasicrystals will enable the unraveling of the fundamental relationship between the structure and magnetism in aperiodic materials. Print Text Size: A A A Subscribe FeedbackShare Page

104

Processing to Control Morphology and Texture in Magnetic Materials  

Science Conference Proceedings (OSTI)

... in Nanocrystalline Soft Magnetic Alloys Effect of Particle Size on the Coercivity of R-Fe-B (R=Nd, Pr) Powders Prepared by Surfactant-Assisted Ball Milling.

105

Procedures for sprinkler anchor installation on surfaces with fireproofing materials  

SciTech Connect

Procedures were developed for limiting the release of fibers from fireproofing material during sprinkler hanger anchor installation on steel deck/concrete floor slab surfaces. These procedures were needed by the General Services Administration (GSA) for installation of sprinkler systems in buildings having fireproofing containing asbestos. A prototype floor slab having spray-on friable mineral wool fireproofing was used in laboratory tests. The mineral-wool fireproofing was used as a model system for fireproofing containing asbestos. The various combinations of mechanical anchoring procedures (use of drills or powder-actuated gun) and encapsulation procedures tested limited the fiber release to a range of values of 0.000 to 0.055 f/cc (fibers per cubic centimeter) as compared to a range of values of 0.26 to 0.82 f/cc for procedures without encapsulation. Encapsulation was shown to be effective as evidenced by much higher levels of fiber release during testing without encapsulation. Because there is no known correlation between the release of mineral-wool fibers and asbestos fibers, it was recommended that the procedures developed be evaluated by GSA in buildings having fireproofing containing asbestos. An air-sampling protocol was developed for use by GSA in evaluating the procedures in the field. Subsequently field tests were conducted by GSA. The laboratory and field studies provided GSA with an effective procedure, measurement method, and decision tool for installing sprinkler hanger anchors in steel deck/concrete floor slabs having fireproofing materials.

Mathey, R.G.; Knab, L.I.; Gross, J.L.; Small, J.A.

1988-02-01T23:59:59.000Z

106

The improved technique of electric and magnetic parameters measurements of powdered materials  

Science Conference Proceedings (OSTI)

This paper presents the measurement technique that allows to determine the relative permittivity and permeability of powdered materials. Measurements are realized in a coaxial transmission line which guarantees the broad band frequency characterization. ... Keywords: Absorbing materials, Magnetic materials, Microwave measurements, Permittivity and permeability measurements, Powdered ferrite measurements, Scattering parameters

Roman Kubacki; Leszek Nowosielski; Rafa? Przesmycki

2011-11-01T23:59:59.000Z

107

Condensed Matter and Magnetic Science, MPA-CMMS: Materials Physics and  

NLE Websites -- All DOE Office Websites (Extended Search)

feature banner feature banner banner Condensed Matter and Magnet Science The Condensed Matter and Magnet Science Group (MPA-CMMS) is comprised of research scientists, technicians, postdocs, and students specializing in experimental physics research, with a strong emphasis on fundamental condensed matter physics with complimentary thrusts in correlated electron materials, high magnetic-field science and technology, thermal physics, and actinide chemistry. MPA-CMMS hosts the Pulsed Field Facility of the National High Magnetic Field Laboratory (NHMFL-PFF) located at TA-35 while new material synthesis, low temperature expertise, and various low-energy spectroscopies are located at TA-3. Our actinide chemistry activities occur at RC-1 (TA-48). The NHMFL-PFF is a national user facility for high magnetic field science sponsored primarily by the National Science Foundation's Division of Materials Research, with branches at Florida State University, the University of Florida, and Los Alamos National Laboratory. (Check out NHMFL Web site for more details.)

108

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

109

Surface Chemistry and Activity of SOFC Cathode Materials as Thin ...  

Science Conference Proceedings (OSTI)

However, the surface properties of oxides in SOFC conditions are poorly understood. To build correlations between surface characteristics and properties, films...

110

Properties of diverted plasmas with magnetically expanded flux surfaces  

DOE Green Energy (OSTI)

Vertical elongated 1.3:1 elliptical plasmas in which the outermost flux surfaces are magnetically expanded and diverted by external coils into the lower half of the Doublet III vacuum vessel are described. Approximately 5 cm of the nominal 45 cm plasma minor radius is diverted to the lower chamber. The diverted flux is expanded by more than a factor of ten before reaching the vessel wall. Photographic measurements show diffused hydrogen recycling light in the lower half of the vessel, with greatly reduced recycling at the normal limiters, and no evidence of localized particle flow to the vessel wall. A significant amount (approx. 50%) of the ohmic power is radiated in the expanded boundary region. Comparison of similar low density plasmas (approx. 2 x 10/sup 13/ cm/sup -3/) with and without the expanded boundary shows that (1) the expanded boundary reduces the influx of nickel and oxygen impurities by an order of magnitude, (2) the boundary also reduces the influx of injected argon and helium by a similar factor, and (3) the concentration of argon in a non-diverted plasma is reduced by a factor of 10 when the expanded boundary is turned on. The central radiated power falls by an order of magnitude, to less than 0.01 W/cm/sup 3/. Similarly, Z/sub eff/(0) drops from 3.2 to 2.1.

Ali Mahdavi, M.; Ohyabu, N.; Baker, D.R.

1980-07-01T23:59:59.000Z

111

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

112

Magnetic Materials for Energy Applications IV: High Performance ...  

Science Conference Proceedings (OSTI)

... Materials for Power Electronics, Power Conditioning and Power Conversion II) ... for real-life modeling of various devices, such as transformers and motors.

113

Soft Magnetic Materials for High Power and High Frequency Power ...  

Science Conference Proceedings (OSTI)

Symposium, Advanced Materials for Power Electronics, Power Conditioning, and ... are in high demand for the next generation of miniaturized power electronics.

114

Application of Metal Injection Molding to Soft Magnetic Materials  

Science Conference Proceedings (OSTI)

Advances in Current Activated Tip-Based Sintering (CATS) Advances in Synthesis and Densification of Heterogeneous Materials Application of Metal Injection...

115

High Entropy Alloys a New Class of Structural Materials: Magnetism ...  

Science Conference Proceedings (OSTI)

Perspectives on Phonons and Electron-Phonon Scattering in High-Temperature Superconductors Prediction and Design of Materials from Crystal Structures to...

116

Kazuhiro Hono, Magnetic Materials Center Managing Director, NIMS...  

NLE Websites -- All DOE Office Websites (Extended Search)

Materials in Japan SessionA7HonoNIMS.pdf More Documents & Publications Tom Lograsso, Ames Laboratory (Iowa State University), Future Directions in Rare Earth Research:...

117

Hard surfaced polymeric materials by ion beam processing  

DOE Green Energy (OSTI)

Initially, both General Motors and Lockheed Martin Energy Systems, Inc. were interested in altering the surface properties of polymers using ion beam technologies. Specifically, GM wished to treat the nylon that is used to encapsulate automotive assemblies so that it would be impervious to the alcohols and ethers used in present day blends of gasoline. Fuel oxygenates such as methanol can rapidly permeate the nylon encapsulant and tend to corrode the components within the assemblies. Once the CRADA was initiated, GM learned about the cleaning/decontamination expertise that was available at the Oak Ridge Y-12 Plant. Because GM was also interested in solving contamination issues related to these assemblies, GM worked with Lockheed Martin Energy Systems, Inc. to amend the CRADA to include such issues. Y-12 was eager to share its environmentally friendly, cleaning/decontamination expertise and also to expand upon its knowledge in this area. GM provided funds into the CRADA in order to address these contamination issues. Further on into the CRADA, GM put even more emphasis on the decontamination issues. This change in direction resulted because of rapid progress on the decontamination issues and, secondly, because GM changed its component material from nylon to the highly impervious polyphenylene sulfide.

Simandl, R.F. [Lockheed Martin Energy Systems, Inc., Oak Ridge, TN (United States); Rose, D. [Delphi Energy and Engine Management Systems, Flint, MI (United States)

1996-09-27T23:59:59.000Z

118

Surface passivation process of compound semiconductor material using UV photosulfidation  

DOE Patents (OSTI)

A method for passivating compound semiconductor surfaces by photolytically disrupting molecular sulfur vapor with ultraviolet radiation to form reactive sulfur which then reacts with and passivates the surface of compound semiconductors.

Ashby, Carol I. H. (Edgewood, NM)

1995-01-01T23:59:59.000Z

119

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

120

Surfaces and Interfaces in Nanostructured Materials II (Electronic ...  

Science Conference Proceedings (OSTI)

Jun 1, 2007 ... Topics explored in this publication include interfacial modification and surface engineering approaches at the nanoscale; biology- and...

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

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

122

Dynamic high pressure process for fabricating superconducting and permanent magnetic materials  

DOE Patents (OSTI)

Shock wave formation of thin layers of materials with improved superconducting and permanent magnetic properties and improved microstructures is disclosed. The material fabrication system includes a sandwiched structure including a powder material placed between two solid members to enable explosive shock consolidation. The two solid members are precooled to about 80--100 K to reduce the residual temperatures attained as a result of the shock wave treatment, and thereby increase the quench rate of the consolidated powder. 9 figs.

Nellis, W.J.; Geballe, T.H.; Maple, M.B.

1990-03-13T23:59:59.000Z

123

Dynamic high pressure process for fabricating superconducting and permanent magnetic materials  

DOE Patents (OSTI)

Shock wave formation of thin layers of materials with improved superconducting and permanent magnetic properties and improved microstructures. The material fabrication system includes a sandwiched structure including a powder material placed between two solid members to enable explosive shock consolidation. The two solid members are precooled to about 80.degree.-100.degree. K. to reduce the residual temperatures attained as a result of the shock wave treatment, and thereby increase the quench rate of the consolidated powder.

Nellis, William J. (Berkeley, CA); Geballe, Theodore H. (Woodside, CA); Maple, M. Brian (Del Mar, CA)

1990-01-01T23:59:59.000Z

124

Hydrogenated Bilayer Wurtzite SiC Nanofilms: A Two-Dimensional Bipolar Magnetic Semiconductor Material  

E-Print Network (OSTI)

Recently, a new kind of spintronics materials, bipolar magnetic semiconductor (BMS), has been proposed. The spin polarization of BMS can be conveniently controlled by a gate voltage, which makes it very attractive in device engineering. Now, the main challenge is finding more BMS materials. In this article, we propose that hydrogenated wurtzite SiC nanofilm is a two-dimensional BMS material. Its BMS character is very robust under the effect of strain, substrate, or even a strong electric field. The proposed two-dimensional BMS material paves the way to use this promising new material in an integrated circuit.

Yuan, Long; Yang, Jinlong

2012-01-01T23:59:59.000Z

125

The mechanical alignment of particles for use in fabricating superconducting and permanent magnetic materials  

DOE Patents (OSTI)

Invention is related to the manufacture of high-quality mechanically aligned superconducting materials using oriented platelet-shaped powder particles, fibers, crystals, and other oriented forms of the recently discovered high-{Tc} class of superconducting ceramics, as well as other superconducting materials. It is also related to the use of these oriented materials in the manufacture of high quality permanent magnetic materials. This pretreatment optimizes the final crystallographic orientation and, thus, properties in these constructs. Such materials as superconducting fibers, needles and platelets are utilized. 11 figs.

Nellis, W.J.; Maple, M.B.

1990-01-24T23:59:59.000Z

126

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

Energy.gov (U.S. Department of Energy (DOE)) Indexed Site

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...

127

Adjustable Permanent Quadrupoles Using Rotating Magnet Material Rods for the Next Linear Collider  

Science Conference Proceedings (OSTI)

The proposed Next Linear Collider (NLC) will require over 1400 adjustable quadrupoles between the main linacs' accelerator structures. These 12.7 mm bore quadrupoles will have a range of integrated strength from 0.6 to 132 Tesla, with a maximum gradient of 135 Tesla per meter, an adjustment range of +0-20% and effective lengths from 324 mm to 972 mm. The magnetic center must remain stable to within 1 micrometer during the 20% adjustment. In an effort to reduce estimated costs and increase reliability, several designs using hybrid permanent magnets have been developed. All magnets have iron poles and use either Samarium Cobalt or Neodymium Iron to provide the magnetic fields. Two prototypes use rotating rods containing permanent magnetic material to vary the gradient. Gradient changes of 20% and center shifts of less than 20 microns have been measured. These data are compared to an equivalent electromagnet prototype.

James T Volk et al.

2001-09-24T23:59:59.000Z

128

THERMAL IMAGING OF ACTIVE MAGNETIC REGERNERATOR MCE MATERIALS DURING OPERATION  

SciTech Connect

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

2012-01-01T23:59:59.000Z

129

Generation of electro-magnetic oscillation in surface multijunction MOMOM  

Science Conference Proceedings (OSTI)

An intergrated surface multijunction MOMOM (metal-oxide-metal-oxide-metal) is reported and coherent electromagnetic oscillation is observed in the low frequency range.

Liao Shiqiang; Wang Yuzhu

1986-04-01T23:59:59.000Z

130

Theoretical studies of surface reactions on metals and electronic materials  

DOE Green Energy (OSTI)

Studies of a variety of adsorbates on Ni have been completed; adsorption energies were determined for CH, CH[sub 2], CH[sub 3], H, NH[sub 3], H[sub 2]O, and C[sub 6]H[sub 6] on Ni(111). A refined calculation of the reaction of methane with Ni was completed. Other studies included H[sub 2] and SiH[sub 4] adsorption/decomposition on Si surfaces, Si-Si dimer bond length, activity energy barriers for reaction of CH[sub 4]and CH[sub 3]F with Si(111). Studies were begun on deposition of C on Ni(111). New directions were explored for reaction of methane with transition metal surfaces; work was completed for a Ni(111) surface containing a substitutional iron atom. Twenty abstracts of papers are presented.

Whitten, J.L.

1993-01-31T23:59:59.000Z

131

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

132

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

133

What Can we Learn About Battery Materials from Their Magnetic Properties  

SciTech Connect

Electrode materials for Li-ion batteries should combine electronic and ionic conductivity, structural integrity, and safe operation over thousands of lithium insertion and removal cycles. The quest for higher energy density calls for better understanding of the redox processes, charge and mass transfer occurring upon battery operation. A number of techniques have been used to characterize long-range and local structure, electronic and ionic transport in bulk of active materials and at interfaces, with an ongoing move toward in situ techniques determining the changes as they happen. This paper reviews several representative examples of using magnetic properties toward understanding of Li-ion battery materials with a notion to highlight the intimate connection between the magnetism, electronic and atomic structure of solids, and to demonstrate how this connection has been used to reveal the fine electronic and atomic details related to the electrochemical performance of the battery materials.

N Chernova; G Nolis; F Omenya; H Zhou; Z Li; M Whittingham

2011-12-31T23:59:59.000Z

134

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 in these materials is also to unravel the factors governing ion and electron transport within the lattice. Lithium de

Ryan, Dominic

135

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

136

Maximization of No-Load Flux Density in Surface Mounted Permanent Magnet Motors Frdric DUBAS, Christophe ESPANET & Abdellatif MIRAOUI.  

E-Print Network (OSTI)

Maximization of No-Load Flux Density in Surface Mounted Permanent Magnet Motors Frédéric DUBAS mounted permanent magnet motors having a direction of parallel or radial magnetization [1]. I expression of the optimal thickness of the magnet which make it possible to maximize the no-load flux density

Paris-Sud XI, Université de

137

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

138

Heating surface materials effect on subcooled flow boiling heat transfer of R134a  

Science Conference Proceedings (OSTI)

In this study, subcooled flow boiling of R134a on copper (Cu) and stainless steel (SS) heating surfaces was experimentally investigated from both macroscopic and microscopic points of view. By utilizing a high-speed digital camera, bubble growth rate, bubble departure size, and nucleation site density, were able to be observed and analyzed from the microscopic point of view. Macroscopic characteristics of the subcooled flow boiling, such as heat transfer coefficient, were able to be measured as well. Experimental results showed that there are no obvious difference between the copper and the stainless surface with respect to bubble dynamics, such as contact angle, growth rate and departure size. On the contrary, the results clearly showed a trend that the copper surface had a better performance than the stainless steel surface in terms of heat transfer coefficient. It was also observed that wall heat fluxes on both surfaces were found highly correlated with nucleation site density, as bubble hydrodynamics are similar on these two surfaces. The difference between these two surfaces was concluded as results of different surface thermal conductivities.

Ling Zou; Barclay G. Jones

2012-11-01T23:59:59.000Z

139

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

140

Role of surface coating on cathode materials for lithium-ion batteries.  

Science Conference Proceedings (OSTI)

Surface coating of cathode materials has been widely investigated to enhance the life and rate capability of lithium-ion batteries. The surface coating discussed here was divided into three different configurations which are rough coating, core shell structure coating and ultra thin film coating. The mechanism of surface coating in achieving improved cathode performance and strategies to carry out this surface modification is discussed. An outlook on atomic layer deposition for lithium ion battery is also presented.

Chen, Z.; Qin, Y.; Amine, K.; Sun, Y.-K. (Chemical Sciences and Engineering Division); (Hanyang Univ.)

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.


141

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

142

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

E-Print Network (OSTI)

The work presented herein describes efforts to synthesize and characterize new types of cyanide-bridged molecular materials encompassing both discrete clusters and extended solids. This investigation focused on the incorporation of anisotropic 4d and 5d transition metal ion building blocks into such materials. In this vein, systematic studies on the magnetic properties of families of these cyano-bridges species were conducted and these new materials represent a new addition to the field of cyanide chemistry incorporating for the first time the hexacyanometallates of [Ru(CN)6]3- and [Os(CN)6]3- into discrete molecules and extended networks. These compounds will serve as models for new theoretical studies in understanding the role of magnetic exchange interactions, both isotropic and anisotropic, in the study of nanomagnetic materials. Results were obtained from using the well known octacyanometallates of MoV and WV as building blocks for the synthesis and the magnetic investigation of both trigonal bipyramidal and pentadecanuclear clusters including the discovery of a new SMM. By expanding the research to previously unused hexacyanometallates, the synthesis and characterization of the first known examples of clusters based on hexacyanoosmate(III) and hexacyanoruthenate(III) building blocks and their use in preparing new theoretical models of magnetic species. A novel pair of clusters is further detailed in the study of the trigonal bipyramidal clusters of [Fe(tmphen)2]3[Os(CN)6]2 and [Fe(tmphen)2]3[Ru(CN)6]2 and an in depth study of the CTIST behavior of these clusters using Mossbauer spectroscopy, variable temperature crystallography, epr, and variable temperature IR measurements. Finally, this work discusses new magnetic Prussian Blue analogs prepared from the hexacyanoosmate(III) and hexacyanoruthenate(III) anions with a comparison to the trigonal bipyramidal clusters presented based on these hexacyanoosmate(III) and hexacyanoruthenate(III) building blocks.

Hilfiger, Matthew Gary

2010-05-01T23:59:59.000Z

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

Method of making active magnetic refrigerant materials based on Gd-Si-Ge alloys  

DOE Patents (OSTI)

An alloy made of heat treated material represented by Gd.sub.5(Si.sub.xGe.sub.1-x).sub.4 where 0.47.ltoreq.x.ltoreq.0.56 that exhibits a magnetic entropy change (-.DELTA.S.sub.m) of at least 16 J/kg K, a magnetostriction of at least 2000 parts per million, and a magnetoresistance of at least 5 percent at a temperature of about 300K and below, and method of heat treating the material between 800 to 1600 degrees C. for a time to this end.

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

2006-10-03T23:59:59.000Z

145

Critical magnetic field of surface superconductivity in lead  

SciTech Connect

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

146

mcdermott-100412 - Argonne National Laboratories, Materials Sicence...  

NLE Websites -- All DOE Office Websites (Extended Search)

MATERIALS SCIENCE COLLOQUIUM SPEAKER: PROF. Robert McDermott University of Wisconsin-Madison TITLE: "1f Noise and Dephasing from Surface Magnetic States in SQUIDs and...

147

Semi-metal-insulator transition on the surface of a topological insulator with in-plane magnetization  

E-Print Network (OSTI)

A thin film of ferromagnetically ordered material proximate to the surface of a three-dimensional topological insulator explicitly breaks the time-reversal symmetry of the surface states. For an out-of-plane ferromagnetic order parameter on the surface, the parity is also broken, since the Dirac fermions become massive. This leads in turn to the generation of a topological Chern-Simons term by quantum fluctuations. On the other hand, for an in-plane magnetization the surface states remain gapless for the non-interacting Dirac fermions. In this work we study the possibility of spontaneous breaking of parity due to a dynamical gap generation on the surface in the presence of a local, Hubbard-like, interaction of strength $g$ between the Dirac fermions. A gap and a Chern-Simons term are generated for $g$ larger than some critical value, g_c, provided the number of Dirac fermions, $N$, is odd. For an even number of Dirac fermions the masses are generated in pairs having opposite signs, and no Chern-Simons term is generated. We discuss our results in the context of recent experiments in EuS/Bi_2Se_3 heterostructures.

Flavio S. Nogueira; Ilya Eremin

2013-04-10T23:59:59.000Z

148

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

SciTech Connect

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, Yulin

2011-05-20T23:59:59.000Z

149

Small magnetic loops connecting the quiet surface and the hot outer atmosphere of the Sun  

E-Print Network (OSTI)

Sunspots are the most spectacular manifestation of solar magnetism, yet, 99% of the solar surface remains 'quiet' at any time of the solar cycle. The quiet sun is not void of magnetic fields, though; they are organized at smaller spatial scales and evolve relatively fast, which makes them difficult to detect. Thus, although extensive quiet Sun magnetism would be a natural driver to a uniform, steady heating of the outer solar atmosphere, it is not clear what the physical processes involved would be due to lack of observational evidence. We report the topology and dynamics of the magnetic field in very quiet regions of the Sun from spectropolarimetric observations of the Hinode satellite, showing a continuous injection of magnetic flux with a well organized topology of Omega-loop from below the solar surface into the upper layers. At first stages, when the loop travels across the photosphere, it has a flattened (staple-like) geometry and a mean velocity ascent of $\\sim3$ km/s. When the loop crosses the minimum...

Gonzalez, M J Martinez; Ramos, A Asensio; Rubio, L R Bellot

2010-01-01T23:59:59.000Z

150

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

Science Conference Proceedings (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

151

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

152

Imaging magnetic sources in the presence of superconducting surfaces : model&experiment  

DOE Green Energy (OSTI)

The forward physics model describing the effect of a superconducting surface on the magnetic field distribution resulting from specific magnetic sources has numerous applications ranging from basic physics experiments to large superconducting magnets used in energy storage and magnetic resonance imaging. In this paper, we describe the novel application of a superconducting imaging surface (SIS) to enhance the performance of systems designed to directly observe and localize human brain function. Magnetoencephalography (MEG) measures the weak magnetic fields emanating from the brain as a direct consequence of the neuronal currents resulting from brain function[1]. The extraordinarily weak magnetic fields are measured by an array of SQUID (Superconducting QUantum Interference Device) sensors. The position and vector characteristics of these neuronal sources can be estimated from the inverse solution of the field distribution at the surface of the head. In addition, MEG temporal resolution is unsurpassed by any other method currently used for brain imaging. Although MEG source reconstruction is limited by solutions of the electromagnetic inverse problem, constraints used for source localization produce reliable results. A novel MEG system incorporating a SIS has been designed and built at Los Alamos with the goal of dramatically improving source localization accuracy while mitigating limitations of current systems (e.g. low signal-to-noise, cost, bulk). We incorporate shielding and source field measurement into an integrated design and combine the latest SQUID and data acquisition technology. The Los Alamos MEG system is based on the principal that fields from nearby sources measured by a SQUID sensor array while the SIS simultaneously shields the sensor array from distant noise fields. In general, Meissner currents flow in the surface of superconductors, preventing any significant penetration of magnetic fields. A hemispherical SIS with a brim, or helmet, surrounds the SQUID sensor array largely sheilding the SQUID sensors from sources outside the helmet. We present the general derivation of the forward model used to describe the effect of a SIS on source fields. Experimental data for the SIS-MEG system are compared with computed field distributions for a comprehensive set of sources.

Matlachov, A. N. (Andrei N.); Espy, M. A. (Michelle A.); Volegov, P. (Petr); Flynn, E. R. (Edward. R.); Maharajh, K. (Keeran); Kraus, Robert H., Jr.

2001-01-01T23:59:59.000Z

153

SEY and Surface Analysis Measurements on FNAL Main Injector Ring S/S Beam Chamber Material  

DOE Green Energy (OSTI)

Material was provided by Dr. Weiren Chou, FNAL. Both mildly-activated used, and new sections of stainless steel (type 316L) beam chamber were measured. Centimeter-sized coupons were cleanly dry-cut from the large flat surface (called ''flat side'' in the plots) and from the ID end (inside diameter of the ring, in the case of the used material) and narrow end (in the case of the new material). The unused material was ultra-soniced in acetone (to remove storage residue), then rinsed with ethanol and blown dry with filtered N{sub 2}-gas, to simulate new chamber installation final rinse. Used material was installed, as cut. Surface chemistry was measured using x-ray photoelectron spectroscopy (sometimes called ''ESCA''). With this technique, soft x-rays (1486 eV) illuminate the sample, penetrating into the surface ten microns. Photoelectrons are generated from energy levels of the constituent compounds/elements present. Those electrons, within 5 nm or so of the surface, escape without energy loss and preserve valence information about the atomic levels from which they were generated. An electron energy analyzer, of good energy resolution, measures the photoelectron energy, thereby yielding both valence (chemical) information and relative atomic abundances in the top 5 nm of surface. Using appropriate sensitivity factors, these intensities are converted to a semi-quantitative (surface atom %) concentration in the analyzed layer. As a benchmark, the limit for carbon contamination on vacuum components for UHV use at SLAC is 50 at%. That corresponds to about 8-10 monolayers of elemental carbon. XPS does not detect hydrogen because it has no electrons after bonding. Generally, hydrides do not show evidence of ''chemical shift'' of the binding energy of the metal lines.

Kirby, Robert E.; /SLAC

2006-09-18T23:59:59.000Z

154

Probability Density Functions to Represent Magnetic Fields at the Solar Surface  

E-Print Network (OSTI)

Numerical simulations of magneto-convection and analysis of solar magnetogram data provide empirical probability density functions (PDFs) for the line-of-sight component of the magnetic field. In this paper, we theoretically explore effects of several types of PDFs on polarized Zeeman line formation. We also propose composite PDFs to account for randomness in both field strength and orientation. Such PDFs can possibly mimic random fields at the solar surface.

Sampoorna, M

2009-01-01T23:59:59.000Z

155

Plasma equilibrium equations in coordinates connected with magnetic surfaces. Exact equilibrium solutions  

E-Print Network (OSTI)

A representation of the static MHD equilibrium system in coordinates connected with magnetic surfaces is suggested. It is used for producing families of non-trivial 3D exact solutions of isotropic and anisotropic plasma equilibria in different geometries, with and without dynamics, and often without geometrical symmetries. The ways of finding coordinates in which exact equilibria can be constructed are discussed; examples and their applications as physical models are presented.

Alexei F. Cheviakov

2004-10-19T23:59:59.000Z

156

An integrated method for material properties characterization based on pulsed laser generated surface acoustic waves  

Science Conference Proceedings (OSTI)

A novel integrated method enabling the study of nano-structured materials is presented, which is based on the imaging and monitoring of the spatiotemporal evolution of short-pulse-laser-generated Surface Acoustic Waves (SAWs). The method combines a 3D ... Keywords: Dynamic laser interferometry, Finite Elements, Nano-acoustics, Nanostructures

Yannis Orphanos, Vasilis Dimitriou, Evaggelos Kaselouris, Efthimios Bakarezos, Nikolaos Vainos, Michael Tatarakis, Nektarios A. Papadogiannis

2013-12-01T23:59:59.000Z

157

Ultra-soft x-ray absorption spectroscopy: A bulk and surface probe of materials  

SciTech Connect

Direct comparisons between surface and bulk of diverse materials can be made by simultaneous electron yield (5 nm depth sensitivity) and fluorescence yield (200 nm) ultra soft x-ray absorption spectroscopy measurements utilizing a rapid sample interchange apparatus. For example the orientations of functional groups have been characterized at and near the surface of a series of model polymeric materials highlighting the chemical and molecular sensitivity of ultra soft x-ray absorption spectroscopy. In addition we discuss a bulk sensitive use of fluorescence yield to non destructively study a buried metal polymer interface. A second bulk sensitive example is the use of fluorescence yield oxygen K near edge x-ray spectroscopy as a method to determine the hole state density of high Tc materials.

Fischer, D.A. [National Institute of Standards and Technology, Gaithersburg, MD (United States); Mitchell, G.E.; Dekoven, B.M. [Dow Chemical Co., Midland, MI (United States); Yeh, A.T.; Gland, J.L. [Michigan Univ., Ann Arbor, MI (United States); Moodenbaugh, A.R. [Brookhaven National Lab., Upton, NY (United States)

1993-06-01T23:59:59.000Z

158

Ultra-soft x-ray absorption spectroscopy: A bulk and surface probe of materials  

SciTech Connect

Direct comparisons between surface and bulk of diverse materials can be made by simultaneous electron yield (5 nm depth sensitivity) and fluorescence yield (200 nm) ultra soft x-ray absorption spectroscopy measurements utilizing a rapid sample interchange apparatus. For example the orientations of functional groups have been characterized at and near the surface of a series of model polymeric materials highlighting the chemical and molecular sensitivity of ultra soft x-ray absorption spectroscopy. In addition we discuss a bulk sensitive use of fluorescence yield to non destructively study a buried metal polymer interface. A second bulk sensitive example is the use of fluorescence yield oxygen K near edge x-ray spectroscopy as a method to determine the hole state density of high Tc materials.

Fischer, D.A. (National Institute of Standards and Technology, Gaithersburg, MD (United States)); Mitchell, G.E.; Dekoven, B.M. (Dow Chemical Co., Midland, MI (United States)); Yeh, A.T.; Gland, J.L. (Michigan Univ., Ann Arbor, MI (United States)); Moodenbaugh, A.R. (Brookhaven National Lab., Upton, NY (United States))

1993-01-01T23:59:59.000Z

159

Yield criteria for quasibrittle and frictional materials: a generalization to surfaces with corners  

E-Print Network (OSTI)

Convexity of a yield function (or phase-transformation function) and its relations to convexity of the corresponding yield surface (or phase-transformation surface) is essential to the invention, definition and comparison with experiments of new yield (or phase-transformation) criteria. This issue was previously addressed only under the hypothesis of smoothness of the surface, but yield surfaces with corners (for instance, the Hill, Tresca or Coulomb-Mohr yield criteria) are known to be of fundamental importance in plasticity theory. The generalization of a proposition relating convexity of the function and the corresponding surface to nonsmooth yield and phase-transformation surfaces is provided in this paper, together with the (necessary to the proof) extension of a theorem on nonsmooth elastic potential functions. While the former of these generalizations is crucial for yield and phase-transformation condition, the latter may find applications for potential energy functions describing phase-transforming materials, or materials with discontinuous locking in tension, or contact of a body with a discrete elastic/frictional support.

Andrea Piccolroaz; Davide Bigoni

2009-04-24T23:59:59.000Z

160

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

Science Conference Proceedings (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

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

Magnetic Systems Mimic Granular Materials | U.S. DOE Office of...  

Office of Science (SC) Website

behavior of magnetic domain fluctuations near phase transitions will enable the control of the noise levels and help to improve the performance of future magnetic...

162

Structure and dynamics of material surfaces, interphase-interfaces and finite aggregates, Progress report, November 1, 1994--October 31, 1995  

SciTech Connect

The focus of the research program supported by this grant is the formulation, development, implementation and application of modeling strategies and large-scale computer simulation methods for studies of critical issues in three main areas: (1) Physical and chemical properties of atomic and molecular clusters and the origins of size-evolutionary patterns of materials properties; charging and fission of atomic and molecular clusters-energetics, geometry, and electronic structure of metallic, ionic and semi-conductor clusters; cluster collisions and cluster reactions; metal-insulator transitions in finite systems; and nanocluster assemblies. (2) Tribological Interactions, Nanomechanics, Thin Film Lubrication, and dynamical and rheological properties of thin films of complex molecular liquids. (3) Surface processing, the stablity of nanostructures on surfaces, the mechanical and electric properties of interfacial junctions, and the electric, magnetic and spectroscopic properties of nano- and micro-structures, such as dots, antidots and point-contacts. During the current report period research efforts were aimed toward the above objectives.

Landman, U.

1995-12-31T23:59:59.000Z

163

Microsoft Word - Poster Abstract_2010_CMU_High Surface Area Materials.docx  

NLE Websites -- All DOE Office Websites (Extended Search)

1th Annual SECA Workshop Poster Abstract 1th Annual SECA Workshop Poster Abstract Topic: High Surface Area, Mesoporous (La, Sr)MnO 3 For Solid Oxide Fuel Cell Cathodes Robin Chao, Graduate Student in Carnegie Mellon University 5700 Bunkerhill St. Apt 705, Pittsburgh, PA 15206 USA, hchao@andrew.cmu.edu, 412-260-5687 Dr. John Kitchin, Professor of Chemical Engineering in Carnegie Mellon University 5000 Forbes Ave, Pittsburgh PA, 15213, jkitchin@andrew.cmu.edu, 412-268-7803 Dr. Paul Salvador, Professor of Material Science and Engineering in Carnegie Mellon University 149 Roberts Eng Hall, Pittsburgh, PA 15213, paul7@andrew.cmu.edu, 412-268-2702 Abstract: The efficiency of the solid oxide fuel cell is limited by the cathode polarizations. One essential approach is to include high-surface-area cathode materials into the fabrication. However, conventional synthesis methods to

164

Excitation of surface plasma waves by an electron beam in a magnetized dusty plasma  

Science Conference Proceedings (OSTI)

An electron beam drives surface plasma waves to instability on a vacuum magnetized dusty plasma interface and in a magnetized dusty plasma cylinder via Cerenkov and fast cyclotron interaction. The dispersion relation of a surface plasma wave has been derived and it has been shown that the phase velocity of waves increases with increase in relative density {delta}(=n{sub i0}/n{sub e0}), where n{sub i0} is the ion plasma density and n{sub e0} is the electron plasma density of negatively charged dust grains. The frequency and the growth rate of the unstable wave instability also increases with {delta}. The growth rate of the instability increases with beam density and scales as the one-third power of the beam density in Cerenkov interaction and is proportional to the square root of beam density in fast cyclotron interaction. The dispersion relation of surface plasma waves has been retrieved from the derived dispersion relation by considering that the beam is absent and there is no dust in the plasma cylinder.

Prakash, Ved; Sharma, Suresh C. [Department of Physics, Maharaja Agrasen Institute of Technology, PSP Area Plot No. 1, Sector 22, Rohini, Delhi 110086 (India)

2009-09-15T23:59:59.000Z

165

Novel Approaches to Surface Analysis and Materials Engineering Using Highly Charged Ions  

DOE Green Energy (OSTI)

Complex problems in materials science require very sensitive, high spatial resolution (< 100 nm) determination of chemical (molecular) structures in near-surface volumes. Slow, highly charged ions (HCIs) provide a new, unique tool for probing chemical structure on a nanometer scale. The authors have explored the potential of these new highly charged ion based techniques in studies of materials with programmatic significance such as high explosives and actinide surfaces. Specifically the are studying HCI based surface analysis techniques (such as secondary ion mass spectrometry, SIMS) that are capable of achieving sensitivity of less than 10{sup 9} atoms/cm{sup 2}. In addition, this technique can determine chemical structure and hydrogen concentration. These attributes make this technique especially important to Laboratory missions in enhanced surveillance and nonproliferation. The unique advantage of HCIs over singly charged ions is the extreme energy density that is deposited into a nanometer-sized near-surface volume at the impact of a single HCI. For example, a Au{sup 69+} ion deposits about 0.5 MJ/cm{sup 3}. This high energy density causes the emission of a large number of secondary particles (electrons, ions, neutral atoms, and clusters) from surfaces. The emitted particles act as probes of the energy dissipation mechanism, and their yields are of technological significance. The HCI-emission microscope concept they developed uniquely combines all three aspects, high spatial resolution with highly sensitive compositional analysis and chemical structure determination. The experiments have shown that individual HCI impacts lead to copious electron emission, over 200 electrons per incident highly charged ion. In addition, highly charged ion induced secondary ion mass spectrometry (HCI-SIMS) provides considerably more information per ion impact than conventional SIMS. Combining these two phenomena provides a unique tool to study important materials issues necessary for the laboratory to accomplish its missions.

Hamza, A.; Schenkel, T.; Barnes, A.; Schneider, D.

2000-02-02T23:59:59.000Z

166

Magnetic Processing A Pervasive Energy Efficient Technology for Next Generation Materials for Aerospace and Specialty Steel Markets  

SciTech Connect

Thermomagnetic Magnetic Processing is an exceptionally fertile, pervasive and cross-cutting technology that is just now being recognized by several major industry leaders for its significant potential to increase energy efficiency and materials performance for a myriad of energy intensive industries in a variety of areas and applications. ORNL has pioneered the use and development of large magnetic fields in thermomagnetically processing (T-MP) materials for altering materials phase equilibria and transformation kinetics. ORNL has discovered that using magnetic fields, we can produce unique materials responses. T-MP can produce unique phase stabilities & microstructures with improved materials performance for structural and functional applications not achieved with traditional processing techniques. These results suggest that there are unprecedented opportunities to produce significantly enhanced materials properties via atomistic level (nano-) microstructural control and manipulation. ORNL (in addition to others) have shown that grain boundary chemistry and precipitation kinetics are also affected by large magnetic fields. This CRADA has taken advantage of ORNLs unique, custom-designed thermo-magnetic, 9 Tesla superconducting magnet facility that enables rapid heating and cooling of metallic components within the magnet bore; as well as ORNLs expertise in high magnetic field (HMF) research. Carpenter Technologies, Corp., is a a US-based industrial company, that provides enhanced performance alloys for the Aerospace and Specialty Steel products. In this CRADA, Carpenter Technologies, Corp., is focusing on applying ORNLs Thermomagnetic Magnetic Processing (TMP) technology to improve their current and future proprietary materials product performance and open up new markets for their Aerospace and Specialty Steel products. Unprecedented mechanical property performance improvements have been demonstrated for a high strength bainitic alloy industrial/commercial alloy that is envisioned to provide the potential for new markets for this alloy. These thermomechanical processing results provide these alloys with a major breakthrough demonstrating that simultaneous improvements in yield strength and ductility are achieved: 12 %, 10%, 13%, and 22% increases in yield strength, elongation, reduction-in-area, and impact energy respectively. In addition, TMP appears to overcome detrimental chemical homogeneity impacts on uniform microstructure evolution.

Mackiewicz-Ludtka, G.; Ludtka, G.M.; Ray, P. (Carpenter Technologies, Inc.); Magee, J. (Carpenter Technologies, Inc.)

2010-09-10T23:59:59.000Z

167

Magnetic anisotropy engineering: Single-crystalline Fe films on ion eroded ripple surfaces  

SciTech Connect

We present a method to preselect the direction of an induced in-plane uniaxial magnetic anisotropy (UMA) in thin single-crystalline Fe films on MgO(001). Ion beam irradiation is used to modulate the MgO(001) surface with periodic ripples on the nanoscale. The ripple direction determines the orientation of the UMA, whereas the intrinsic cubic anisotropy of the Fe film is not affected. Thus, it is possible to superimpose an in-plane UMA with a precision of a few degrees - a level of control not reported so far that can be relevant for example in spintronics.

Liedke, M. O.; Koerner, M.; Lenz, K.; Grossmann, F.; Facsko, S.; Fassbender, J. [Institute of Ion Beam Physics and Materials Research, Helmholtz-Zentrum Dresden-Rossendorf e.V., P.O. Box 510119, 01314 Dresden (Germany)

2012-06-11T23:59:59.000Z

168

Nuclear Magnetic Resonance Laboratory  

Science Conference Proceedings (OSTI)

Nuclear Magnetic Resonance Laboratory. ... A 600 MHz Nuclear Magnetic Resonance Spectrometer. Analytical Data Compilation Reference Materials. ...

2012-10-01T23:59:59.000Z

169

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

170

Modular Permanent Magnet Machine Based on Soft Magnetic *** Burgess-Norton Mfg.Co.  

E-Print Network (OSTI)

of surface permanent magnet motor, and [8] small induction motors. In this paper, novel single phase2005-30 Modular Permanent Magnet Machine Based on Soft Magnetic Composite *** Burgess-Norton Mfg magnetic composite (SMC) material, electric machine design is no longer limited to the traditional iron

Lipo, Thomas

171

Roughness and surface material effects on nucleate boiling heat transfer from cylindrical surfaces to refrigerants R-134a and R-123  

SciTech Connect

This paper presents results of an experimental investigation carried out to determine the effects of the surface roughness of different materials on nucleate boiling heat transfer of refrigerants R-134a and R-123. Experiments have been performed over cylindrical surfaces of copper, brass and stainless steel. Surfaces have been treated by different methods in order to obtain an average roughness, Ra, varying from 0.03 {mu}m to 10.5 {mu}m. Boiling curves at different reduced pressures have been raised as part of the investigation. The obtained results have shown significant effects of the surface material, with brass being the best performing and stainless steel the worst. Polished surfaces seem to present slightly better performance than the sand paper roughened. Boiling on very rough surfaces presents a peculiar behavior characterized by good thermal performance at low heat fluxes, the performance deteriorating at high heat fluxes with respect to smoother surfaces. (author)

Jabardo, Jose M. Saiz [Escuela Politecnica Superior, Universidad de la Coruna, Mendizabal s/n Esteiro, 15403 Ferrol, Coruna (Spain); Ribatski, Gherhardt; Stelute, Elvio [Department of Mechanical Engineering, Escola de Engenharia de Sao Carlos (EESC), University of Sao Paulo (USP), Av. Trabalhador Saocarlense 400 Centro, 13566-590 Sao Carlos, SP (Brazil)

2009-04-15T23:59:59.000Z

172

Synthesis of bulk FeHfBO soft magnetic materials and its loss characterization at megahertz frequency  

SciTech Connect

Magnetic core materials with low loss, high saturation magnetization, large permeability, and operating frequency above 1 MHz are in high demands for the next generation of miniaturized power electronics. Amorphous FeHfB ribbons with thickness around 20 {mu}m have been fabricated through melt-spinning. Different heat treatments were performed on the FeHfB ribbons, and the relations among heat treatments, microstructure, and magnetic properties have been explored. Properties such as coercivity (H{sub c}) of 2.0 Oe and saturation magnetic flux density (B{sub S}) of 1.2 T have been achieved in samples with exchange coupling. The losses can be minimized by balancing the hysteretic and eddy current losses and can be further reduced with additional magnetic field annealing. At 5 MHz with peak magnetic flux density of 20 mT, the materials show core losses comparable to the best ferrites, but with higher permeability value of about 200 and superior saturation induction of more than 1 T.

Zhou Yang; Kou Xiaoming; Warsi Muhammad, Asif; Lin Shuo; Harris, Brendan S.; Parsons, Paul E.; Xiao, John Q. [Department of Physics and Astronomy, University of Delaware, Newark, Delaware 19716 (United States); Mu Mingkai; Lee, Fred C. [Center for Power Electronics System, Virginia Polytechnic and State University, Blacksburg, Virginia 24060 (United States); Zhu Hao [Spectrum Magnetics LLC, Wilmington, Delaware 19804 (United States)

2013-05-07T23:59:59.000Z

173

Dynamic high pressure process for fabricating superconducting and permanent magnetic materials  

DOE Patents (OSTI)

Shock wave formation of superconductive ceramic oxide electric and magnetic circuit elements with improved microstructures and mechanical properties. 10 figs.

Nellis, W.J.; Maple, M.B.; Geballe, T.H.

1987-10-23T23:59:59.000Z

174

Surface Modification of Fuel Cladding Materials with Integral Fuel BUrnable Absorber Boron  

Science Conference Proceedings (OSTI)

Integral fuel burnable absorgers (IFBA) are added to some rods in the fuel assembly to counteract excessive reactivity. These IFBA elements (usually boron or gadolinium) are presently incorporated in the U)2 pellets either by mixing in the pellets or as coatings on the pellet surface. In either case, the incorporation of ifba into the fuel has to be performed in a nuclear-regulated facility that is physically separated from the main plant. These operations tend to be costly and can add from 20 to 30% to the manufacturing cost of the fuel. The goal of this NEER research project was to develop an alternative approach that involves incorporation of IFBA element boron at the surface of the fuel cladding material.

Dr. Kumar Sridharan; Dr. Todd Allen; Jesse Gudmundson; Benjamin Maier

2008-11-03T23:59:59.000Z

175

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

Science Conference Proceedings (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

176

TIME-RESOLVED ANALYSES OF MICROSTRUCTURE IN ADVANCED MATERIALS UNDER MAGNETIC FIELDS AT ELEVATED TEMPERATURES USING NEUTRONS  

Science Conference Proceedings (OSTI)

Fundamental science breakthroughs are being facilitated by high magnetic field studies in a broad spectrum of research disciplines. Furthermore, processing of materials under high magnetic fields is a novel technique with very high science and technological potential. However, currently the capability does not exist to do in-situ time-resolved quantitative analyses at high magnetic field strengths and elevated temperatures. Therefore, most measurements are performed ex situ and do not capture the microstructural evolution of the samples during high field exposure. To address this deficiency, we are developing high field magnet processing and analyses systems at the High Flux Isotope Reactor and the Spallation Neutron Source at the Oak Ridge National Laboratory which will link the analytical capabilities inherent in neutron science to the needs of magnetic processing research. Our goal is to apply advanced neutron scattering techniques to explore time-resolved characterizations of magnetically driven alloy phase transformations under transient conditions. This paper will provide an overview of the current status of this research endeavor with preliminary results obtained on ferrous alloys.

Ludtka, Gerard Michael [ORNL; Klose, Frank Richard [ORNL; Kisner, Roger A [ORNL; Fernandez-Baca, Jaime A [ORNL; Ludtka, Gail Mackiewicz- [ORNL; Wilgen, John B [ORNL; Jaramillo, Roger A [ORNL; Santodonato, Louis J [ORNL; Wang, Xun-Li [ORNL; Hubbard, Camden R [ORNL; Tang, Fei [ORNL

2007-01-01T23:59:59.000Z

177

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

E-Print Network (OSTI)

There is an increasing demand for materials that are physically robust, easily recovered, and able to perform a wide variety of chemical functions. By combining hard and soft matter synergistically, organic-inorganic hybrid materials are potentially useful for a number of applications (e.g. catalysis, separations, sensing). In this respect, organic/ordered mesoporous silica (OMS) hybrids have attracted considerable attention, with an increasing emphasis on complex organic moieties achieved through multi-step reactions and polymerizations. It is on this front that we have focused our work, specifically in regard to polypeptides. Polypeptides are well suited organic components for hybrids as they provide a wide range of possible side chain chemistries (NH2, -SH, -COOH, -OH, etc.), chirality, and have conformations that are known to be responsive to external stimuli (pH, electrolytes, solvents, etc.). Our work has shown that N-carboxyanhydride chemistry offers a facile single step approach to the incorporation of dense polypeptide brushes in OMS. Modifying the initiator loading, pore size, pore topology, and monomer identity significantly impacted the properties of the obtained composites and peptide brush layers. Extending this work, a synthesis paradigm for preferentially grafting poly-L-lysine to the external and internal surfaces of SBA-15, a widely used OMS material, was developed. We observed that the pores of these hybrids could be opened and closed by the reversible swelling of the polypeptide layer. Similarly, novel bifunctional hybrids were synthesized by grafting polypeptides to the external surface of monodisperse OMS spheres that contain a thiol-functionalized core. The accessibility of the internal thiols to a fluorescent dye shows the potential of these hybrids for applications such as controlled uptake/release.

Lunn, Jonathan D.

2010-05-01T23:59:59.000Z

178

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

E-Print Network (OSTI)

Engineering new solid propellant materials requires optimization of several factors, to include energy density, burn rate, sensitivity, and environmental impact. Equally important is the need for materials that will maintain their mechanical properties and thermal stability during long periods of storage. The nanoscale materials considered in this dissertation are proposed metal additives that may enhance energy density and improve combustion in a composite rocket motor. Density Functional Theory methods are used to determine cluster geometries, bond strengths, and energy densities. The ground-state geometries and electron affinities (EAs) for MnxO?: x = 3, 4, y = 1, 2 clusters were calculated with GGA, and estimates for the vertical detachment energies compare well with experimental results. It was found that the presence of oxygen influences the overall cluster moment and spin configuration, stabilizing ferrimagnetic and antiferromagnetic isomers. The calculated EAs range from 1.29-1.84 eV, which is considerably lower than the 3.0-5.0 eV EAs characteristic of current propellant oxidizers. Their use as solid propellant additives is limited. The structures and bonding of a range of Al-cyclopentadienyl cluster compounds were studied with multilayer quantum mechanics/molecular mechanics (QM:MM) methods. The organometallic Al-ligand bonds are generally 55-85 kcal/mol and are much stronger than Al-Al interactions. This suggests that thermal decomposition in these clusters will proceed via the loss of surface metal-ligand units. The energy density of the large clusters is calculated to be nearly 60% that of pure aluminum. These organometallic cluster systems may provide a route to extremely rapid Al combustion in solid rocket motors. Lastly, the properties of COOH-terminated passivating agents were modeled with the GPW method. It is confirmed that fluorinated polymers bind to both Al(111) and Al(100) at two Al surface sites. The oligomers HCOOH, CH3CH2COOH, and CF3CF2COOH chemisorb onto Al(111) with adsorption energies of 10-45 kcal/mol. The preferred contact angle for the organic chains is 65-85 degrees, and adsorption energy weakens slightly with increasing chain length. Despite their relatively weak adsorption energies, fluorinated polymers have elevated melting temperatures, making them good passivation materials for micron-scale Al fuel particles.

Williams, Kristen

2012-08-01T23:59:59.000Z

179

The Development of Material and Fabrication Technologies for ITER Magnet Supports  

Science Conference Proceedings (OSTI)

Technical Paper / First Joint ITER-IAEA Technical Meeting on Analysis of ITER Materials and Technologies

P. Y. Li; C. J. Pan; B. L. Hou; S. L. Han; Z. C. Sun; F. Savary; Y. K. Fu; R. Gallix; N. Mitchell

180

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

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

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

182

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

SciTech Connect

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 30C to 650C, 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 450C, 550C, and 650C 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 650C 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

183

Variation of the magnetic susceptibility of artificial graphite with exposure in the materials testing reactor  

SciTech Connect

The magnetic susceptibility of artificial graphite was determined as a function of exposure in the MTR. Specimens were studied with exposures ranging from 0.07 to 82 {times} 10{sup18} nvt. Fluxes were determined by means of x-ray measurements and resistivity measurements. The dependence of the magnetic susceptibility on exposure in the MTR and also in a Hanford reactor are graphed, and an equivalence factor is calculated.

McCelland, J.D.

1955-02-23T23:59:59.000Z

184

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

185

Effect of beam premodulation on excitation of surface plasma waves in a magnetized plasma  

SciTech Connect

A density modulated electron beam propagating through a vacuum magnetized plasma interface drives electromagnetic surface plasma waves (SPWs) to instability via Cerenkov and fast cyclotron interaction. Numerical calculations of the growth rate and unstable mode frequencies have been carried out for the typical parameters of the SPWs. The growth rate {gamma} of the unstable wave instability increases with the modulation index ({Delta}) and is maximized for {Delta}=1. For {Delta}=0, {gamma} turns out to be {approx}4.32x10{sup 10} rad/s for Cerenkov interaction and {approx}6.81x10{sup 10} rad/s for fast cyclotron interaction. The growth rate of the instability increases with the beam density and scales as one-third power of the beam density in Cerenkov interaction and is proportional to the square root of beam density in fast cyclotron interaction. In addition, the real frequency of the unstable wave increases with the beam-energy and scales as almost one-half power of the beam-energy.

Gupta, Ruby [Department of Physics, Swami Shraddhanand College, University of Delhi, Alipur, Delhi 110036 (India); Sharma, Suresh C. [Department of Physics, Maharaja Agrasen Institute of Technology, PSP Area Plot No.-l, Sector-22, Rohini, Delhi 110086 (India); Prakash, Ved [India Meteorological Department, Ministry of Earth Science, Lodi Road, New Delhi 110003 (India)

2010-11-15T23:59:59.000Z

186

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

SciTech Connect

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

187

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

188

Materials Science Division - Argonne National Laboratories, Materials  

NLE Websites -- All DOE Office Websites (Extended Search)

Home Home About MSD Information Awards Visit MSD Administrative Staff Division Personnel Research Research Groups Condensed Matter Theory Emerging Materials Energy Conversion and Storage Magnetic Films Molecular Materials Neutron and X-ray Scattering Superconductivity and Magnetism Surface Chemistry Synchrotron Radiation Studies Threat Detection and Analysis Group Research Areas Careers in MSD Internal Sites Search Front Slide 1 November 2013 - Patricia Dehmer (second from right), Deputy Director of Science Programs, DOE Office of Science, joined Argonne Director Eric Isaacs(left) and Associate Laboratory Director for Physical Sciences and Engineering Peter Littlewood(second from left) to tour the recently-opened Energy Sciences Building. Among Dehmer's stops was the crystal growth

189

Research - Argonne National Laboratories, Materials Sicence Division  

NLE Websites -- All DOE Office Websites (Extended Search)

Research Research Research Groups in the Materials Science Division Condensed Matter Theory Carries out theoretical work on superconductivity, electronic structure and magnetism. Emerging Materials Emphasizes an integrated materials synthesis and science program that focuses on correlated electron transition metal oxides, chalcogenides with enhanced thermoelectric performance, and novel superconductors, including pnictides and cuprates. Energy Conversion and Storage The energy conversion and storage group focuses on charge-transfer processes, as well as the chemical environment in the vicinity of electrode surfaces. Magnetic Films Research to develop, characterize and investigate the properties of magnetic thin films and superlattices. Molecular Materials Synthesis and characterization of molecular materials that have novel

190

Magnetic Imaging  

Science Conference Proceedings (OSTI)

... data-storage and permanent magnets with increased energy products, in ... Optimization of future materials, including improved yields, requires an ...

2012-10-02T23:59:59.000Z

191

This is a joint session with Magnetic Materials for Energy Applications  

Science Conference Proceedings (OSTI)

Advanced Materials for Power Electronics, Power Conditioning, and Power ... for Use in Energy-efficient Distribution Transformers: presented by Naoki Ito1; Eric...

192

Novel Materials and Phenomenon  

Science Conference Proceedings (OSTI)

Mar 6, 2013 ... Magnetic Materials for Energy Applications -III: Novel Materials and ... In traditional Permanent Magnet Machines, such as motors and...

193

Materials  

NLE Websites -- All DOE Office Websites (Extended Search)

Materials Materials and methods are available as supplementary materials on Science Online. 16. W. Benz, A. G. W. Cameron, H. J. Melosh, Icarus 81, 113 (1989). 17. S. L. Thompson, H. S. Lauson, Technical Rep. SC-RR-710714, Sandia Nat. Labs (1972). 18. H. J. Melosh, Meteorit. Planet. Sci. 42, 2079 (2007). 19. S. Ida, R. M. Canup, G. R. Stewart, Nature 389, 353 (1997). 20. E. Kokubo, J. Makino, S. Ida, Icarus 148, 419 (2000). 21. M. M. M. Meier, A. Reufer, W. Benz, R. Wieler, Annual Meeting of the Meteoritical Society LXXIV, abstr. 5039 (2011). 22. C. B. Agnor, R. M. Canup, H. F. Levison, Icarus 142, 219 (1999). 23. D. P. O'Brien, A. Morbidelli, H. F. Levison, Icarus 184, 39 (2006). 24. R. M. Canup, Science 307, 546 (2005). 25. J. J. Salmon, R. M. Canup, Lunar Planet. Sci. XLIII, 2540 (2012). Acknowledgments: SPH simulation data are contained in tables S2 to S5 of the supplementary materials. Financial support

194

Magnetization Characterization Laboratory  

Science Conference Proceedings (OSTI)

... use of magnetic materials for motors, generators, transformers ... all depend on the specific magnetic characteristics of ... For example, a magnet used in ...

2012-10-23T23:59:59.000Z

195

Learning About Magnets!  

NLE Websites -- All DOE Office Websites (Extended Search)

the the National High Magnetic Field Laboratory Learning About Name A magnet is a material or object that creates a magnetic fi eld. This fi eld is invisible, but it creates a force that can "attract" or "repel" other magnets and magnetic materials, like iron or nickel. What is a Magnet? This bar magnet is a permanent magnet. Permanent magnets can be found in the Earth as rocks and metals. Magnets have

196

Material  

DOE Green Energy (OSTI)

Li(Ni{sub 0.4}Co{sub 0.15}Al{sub 0.05}Mn{sub 0.4})O{sub 2} was investigated to understand the effect of replacement of the cobalt by aluminum on the structural and electrochemical properties. In situ X-ray absorption spectroscopy (XAS) was performed, utilizing a novel in situ electrochemical cell, specifically designed for long-term X-ray experiments. The cell was cycled at a moderate rate through a typical Li-ion battery operating voltage range. (1.0-4.7 V) XAS measurements were performed at different states of charge (SOC) during cycling, at the Ni, Co, and the Mn edges, revealing details about the response of the cathode to Li insertion and extraction processes. The extended X-ray absorption fine structure (EXAFS) region of the spectra revealed the changes of bond distance and coordination number of Ni, Co, and Mn absorbers as a function of the SOC of the material. The oxidation states of the transition metals in the system are Ni{sup 2+}, Co{sup 3+}, and Mn{sup 4+} in the as-made material (fully discharged), while during charging the Ni{sup 2+} is oxidized to Ni{sup 4+} through an intermediate stage of Ni{sup 3+}, Co{sup 3+} is oxidized toward Co{sup 4+}, and Mn was found to be electrochemically inactive and remained as Mn{sup 4+}. The EXAFS results during cycling show that the Ni-O changes the most, followed by Co-O, and Mn-O varies the least. These measurements on this cathode material confirmed that the material retains its symmetry and good structural short-range order leading to the superior cycling reported earlier.

Rumble, C.; Conry, T.E.; Doeff, Marca; Cairns, Elton J.; Penner-Hahn, James E.; Deb, Aniruddha

2010-06-14T23:59:59.000Z

197

Optimal design of a high-speed slotless permanent magnet synchronous generator with soft magnetic composite stator yoke and rectifier load  

Science Conference Proceedings (OSTI)

This paper presents a specific design methodology of a DC generation system using a high-speed slotless generator with surface-mounted magnets and soft magnetic composite (SMC) stator yoke connected to a rectifier. The method is based on an analytical ... Keywords: Eddy currents, High-speed generation system, Optimal design, Permanent magnet machine, Soft magnetic composite material

Ahmed Chebak; Philippe Viarouge; Jrme Cros

2010-10-01T23:59:59.000Z

198

Theoretical studies of surface reactions on metals and electronic materials. Final report, December 1, 1993--May 15, 1996  

DOE Green Energy (OSTI)

In order to achieve accurate energetics for surface reactions, first-principles calculations are performed using a cluster embedding theory. The projects dealing with hydrocarbon reactions and CO adsorption and dissociation on nickel and iron address fundamental questions related to surface reactivity. The study of the dissociation of methane on a nickel surface containing an iron atom is relevant to the use of methane for synthesis of other hydrocarbons and to the general topic of alkane reactivity. Studies of oxygen and sulfur containing compounds are designed to aid in the interpretation of structural and spectroscopic experiments. Silicon surface studies focus on several questions related to chemical vapor deposition reactions and growth of electronic materials. In collaborative work with experimental groups at N.C. State developing diagnostic techniques for monitoring film growth, influences on second harmonic generation arising from chemical modifications of interfaces are explored. The project involving diamond growth explores factors that influence the bonding of carbon to nickel surfaces and surface reactions on carbon. Studies of defects produced by H atom migration in amorphous silicon are related to the degradation of the photovoltaic properties of this material on continued exposure to light.

Whitten, J.L.

1996-05-01T23:59:59.000Z

199

A visual inspection system for evaluating the interior surface of valve stems on material storage container tops  

SciTech Connect

A nondestructive inspection for evaluating the interior surface of the small diameter valve stems on material storage container tops was mandated. The specifications required that the interior surface of the valve stem have a surface finish of {number sign}16 or better. Conventional methods which utilizes mechanical stylus-type''surface analyzing equipment could not extend into the narrow 0.312 inch diameter by 1.5 inch deep hole (of the valve stem). A visual inspection system which exploits the capabilities of a high resolution fiberoptic borescope was designed and assembled to resolve this requirement. This paper discusses the design and inspection features of the aforementioned system and includes several illustrations of inspection results. 6 figs.

Pickett, C.A.

1990-12-01T23:59:59.000Z

200

Anisotropic Curie Temperature Materials  

Science Conference Proceedings (OSTI)

Symposium, Magnetic Materials for Energy Applications -III. Presentation Title, Anisotropic Curie Temperature Materials. Author(s), Harsh Deep Chopra, Jason...

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

Bioinspired Materials Engineering  

Science Conference Proceedings (OSTI)

Conference Tools for Materials Science & Technology 2014 ... structured functional materials with improved and designed (piezo )electrical, magnetic, optical,...

202

magnets  

NLE Websites -- All DOE Office Websites (Extended Search)

I I Painless Physics Articles BEAM COOLING August 2, 1996 By Leila Belkora, Office of Public Affairs ACCELERATION August 16, 1996 By Dave Finley, Accelerator Division Head RF August 30, 1996 By Pat Colestock, Accelerator Division FIXED TARGET PHYSICS September 20, 1996 By Peter H. Garbincius, Physics Section FIXED TARGET PHYSICS PART DEUX October 16, 1996 By Peter H. Garbincius, Physics Section and Leila Belkora, Office of Public Affaris CROSS SECTION November 1, 1996 By Doreen Wackeroth, Theoretical Physics Edited by Leila Belkora, Office of Public Affaris MAGNETS PART I November 15, 1996 By Hank Glass, Technical Support Section Edited by Donald Sena, Office of Public Affairs MAGNETS PART II January 10, 1997 By Hank Glass, Technical Support Section Edited by Donald Sena, Office of Public Affairs

203

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

E-Print Network (OSTI)

Accidents and hazards continue to plague the construction industry. One often overlooked hazard to workers is the potential for flying debris and materials during high winds. This research was designed to evaluate the wind velocity required to create such an airborne hazard with flat surface materials such as plywood. This research was developed to show select correlations between the wind velocity, lifting forces and the susceptibility to movement of large surface area flat sheets of construction material, specifically four feet by eight feet sheets of floordeck plywood weighing 107 pounds. It also examined and evaluated the correlation of a shape coefficient to movement of materials and wind velocities, so that calculations can be made to adequately predict the potential movement of these materials. This will allow construction supervisors to reasonably prepare for such anticipated conditions. The Texas A&M University low speed wind tunnel was used to place a ftffl-scale stack of plywood floor decking material with the air stream flowing over the stack until top sheet separated or lifted from the stack. Next, a half-scale model was placed in the test section of the tunnel with pressure ports attached to a high speed sampling transducer to measure the actual pressures at select velocities. This allowed for a correlation between the ftifl-scale data and the sampled data. Tests were performed for several front and side angles of the wind striking the edge surface of the materials. Velocities were used up to 60 miles per hour full-scale equivalent. The full-scale model achieved lift forces exceeding the material weight of 107 pounds at one orientation angle at a velocity just below 30 miles per hour. This was consistent with the half-scale test pressures for a similar orientation. Various orientations yielded different forces as was anticipated. From this information a pressure coefficient was developed which when applied with a safety factor allows for reasonable calculations to be made to determine potential hazards and adequately secure materials on any sites where large flat materials may be handled or stored.

Madeley, Jack T.

1996-01-01T23:59:59.000Z

204

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  

Science Conference Proceedings (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 todays 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

205

Effects of stabilization temperature on surface area and grain size of representative plutonium materials.  

DOE Green Energy (OSTI)

Calcination at 400-1000C is used throughout the Department of Energy (DOE) complex to stabilize plutonium material for transportation and storage . The objectives of this stabilization are to remove moisture and other potentially water-producing phases, and to ensure that readsorption will not occur before material is placed in welded containers .Such moisture may threaten the integrity of containers through pressurization with radiolytically generated hydrogen. It is also considered valuable to reduce the fine (respirable) fraction of the material to mitigate potential impact of accidents.

Boak, J. M. (Jeremy M.); Dale, D. J. (Deborah J.); Eller, P. G. (Phillip Gary)

2003-01-01T23:59:59.000Z

206

Effects of surface condition on the corrosion of candidate structural materials in a simulated HTGR-GT environment  

DOE Green Energy (OSTI)

A simulated high-temperature gas-cooled reactor (HTGR) helium environment was used to study the effects of surface finish conditions on the subsequent elevated-temperature corrosion behavior of key candidate structural materials. The environment contained helium with 500 ..mu..atm H/sub 2//50 ..mu..atm CO/50 ..mu..atm CH/sub 4//<0.5 ..mu..atm H/sub 2/O at 900/sup 0/C with total test exposure durations of 3000 hours. Specimens with lapped, grit-blasted, pickled, and preoxidized surface conditions were studied. Materials tested included two cast superalloys, IN 100 and IN 713LC; one centrifugally cast high-temperature alloy, HK 40 one oxice-dispersion-strengthened alloy, Inconel MA 754; and three wrought high-temperature alloys, Hastelloy Alloy X, Inconel Alloy 617, and Alloy 800H.

Thompson, L.D.

1980-02-01T23:59:59.000Z

207

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

208

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

209

Magnetic imaging of shipwrecks  

E-Print Network (OSTI)

The ferromagnetic material in a shipwreck on the seabed causes a modification to the earth's magnetic field which can be measured at the surface. Proton magnetometer measurements at the surface are used to locate wrecks. Here I discuss how to interpret such data to explore the shape and orientation of the shipwreck on the seabed. I give details of how to model shipwrecks and deduce the magnetic signal that results. I also discuss how to analyse data in a more general way. As examples, I present and analyse data on the shipwrecks of YSTROOM and BOUBOULINA (ex COLONEL LAMB).

Michael, C

2011-01-01T23:59:59.000Z

210

Surface treated natural graphite as anode material for high-power Li-ion battery applications.  

Science Conference Proceedings (OSTI)

High power application of Li-ion battery in hybrid electrical vehicles requires low cost and safe cell materials. Among the various carbon anode materials used in lithium ion batteries, natural graphite shows the most promise with advantages in performance and cost. However, natural graphite is not compatible with propylene carbonate (PC)-based electrolytes, which have a lower melting point and improved safety characteristics. The problem with it is that the molecules of propylene carbonate intercalate with Li+ into graphite, and that frequently leads to the exfoliation of the graphite matrix.

Liu, J.; Vissers, D. R.; Amine, K.; Barsukov, I. V.; Henry, F.; Doniger, J.; Chemical Engineering; Superior Graphite Co.

2006-01-01T23:59:59.000Z

211

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

212

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

213

Design of a millimetre-scale magnetic surface trap for cold atoms  

E-Print Network (OSTI)

We study a novel millimetre-scale magnetic trap for ultracold atoms, in which the current carrying conductors can be situated outside the vacuum region, a few mm away from the atoms. This design generates a magnetic field gradient in excess of \\SI{1000}{G/cm} at a distance of \\SI{2}{mm} from the conductors. We perform electromagnetic and thermo-mechanical characterisation using Finite Element Methods (FEM). The predicted behaviour has been verified by electrical and thermal measurements on a prototype, but has not been implemented on an apparatus with cold atoms. Operating this trap at the highest gradient allows for rapid evaporative cooling comparable to that achieved by atom chips.

Trypogeorgos, Dimitris

2013-01-01T23:59:59.000Z

214

Materials Reliability Program: Effects of Surface Peening on the Inspectability of Nondestructive Evaluation  

Science Conference Proceedings (OSTI)

To study emerging component repair and mitigation techniques and their potential effects on applied nondestructive evaluation (NDE), the Electric Power Research Institute (EPRI) Materials Reliability Program inspection technical advisory committee funded a multiyear project, which began in 2010. This report investigates the effects of various peening processes on routine applications of NDE inspection techniques.BackgroundAn inspection plan will be part of ...

2013-11-26T23:59:59.000Z

215

Magnetocaloric Materials  

Science Conference Proceedings (OSTI)

Magnetic Materials for Energy Applications IV: Magnetocaloric Materials ... due to cost-effectiveness as well as superior magneto-thermal characteristics. ... metals and p-block elements can be explored in a time- and energy-saving manner.

216

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

SciTech Connect

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

217

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

DOE Green Energy (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

218

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 Andrs

2011-01-01T23:59:59.000Z

219

The Effects of Surface Chemistry on the Properties of Proteins Confined in Nano-porous Materials  

Science Conference Proceedings (OSTI)

The entrapment of proteins using the sol-gel route provides a means to retain its native properties and artificially reproduce the molecular crowding and confinement experienced by proteins in the cell allowing investigation of the physico-chemical and structural properties of biomolecules at the biotic/abiotic interface. The biomolecules are spatially separated and 'caged' in the gel structure but solutes can freely permeate the matrix. Thus, properties such as the folding of ensembles of individual molecules can be examined in the absence of aggregation effects that can occur in solution studies. Green fluorescent protein from Aequorea coerulescens was used as a model protein to examine the unfolding/re-folding properties of protein in silica gels. The recombinant protein was isolated and purified from Escherichia coli extracts by cell lysis, three-phase partitioning, dialysis, and anion exchange chromatography. The purity of the protein was greater than 90% as judged by SDS PAGE gel analysis. Sol-gels were synthesized using tetramethylorthosilicate (TMOS) in combination with, methyltrimethoxyorthosilane (MTMOS), ethyltrimethoxyorthosilane (ETMOS), 3-aminopropyltriethoxysilane (APTES), and 3-glycidoxypropyltrimethoxysilane (GPTMS). The acid induced denaturation and renaturation of GFP was analyzed by UV-visible, fluorescence, and circular dichroism (CD) spectroscopies. No renaturation was observed in gels that were made with TMOS only, and in the presence of APTES, MTMOS, and ETMOS. However, in gels that were made with GPTMS, the CD and UV-visible spectra indicated that the protein had refolded. The fluorescence emission spectrum indicated that approximately 20% of fluorescence had returned. This study highlights the importance of the surface chemistry of the silica gels for the refolding properties of the entrapped GFP. Future studies will investigate the effect of surface chemistry on the thermal and solvent stability of the entrapped protein.

Garrett, Latasha M [ORNL; O'Neill, Hugh Michael [ORNL

2007-01-01T23:59:59.000Z

220

Vortex Dynamics in NanoScale Materials  

NLE Websites -- All DOE Office Websites (Extended Search)

Into the Vortex: Dynamics in Nanoscale Materials Into the Vortex: Dynamics in Nanoscale Materials Micron and nanosized magnets are of great interest for their potential applications in new electronic devices, such as magnetic random access memories. As the size of magnets is reduced to a 1-micron scale and below, the boundaries (surfaces, perimeters, etc) of the objects begin to profoundly influence both the static and dynamic behavior of the materials. Researchers from Argonne's Materials Science Division (MSD), Center for Nanoscale Materials (CNM), and Advanced Photon Source (APS) have recently examined the dynamics of 3- to 7-micron-diameter NiFe alloy disks with a combination of theoretical calculations and a new time-resolved magnetic imaging technique using synchrotron-based x-ray photoemission electron

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

Optimizing a low-energy electron diffraction spin-polarization analyzer for imaging of magnetic surface structures  

Science Conference Proceedings (OSTI)

A newly designed scanning electron microscope with polarization analysis (SEMPA or spin-SEM) for the acquisition of magnetic images is presented. Core component is the spin detector, based on the scattering of low-energy electrons at a W(100) surface in ultrahigh vacuum. The instrument has been optimized with respect to ease of handling and efficiency. The operation and performance of a general low-energy electron diffraction (LEED) detector for SEMPA have been modeled in order to find the optimum operating parameters and to predict the obtainable image asymmetry. Based on the energy dependence of the secondary electron polarization and intensity, the detector output is simulated. For our instrument with optimized performance we demonstrate experimentally 8.6% polarization asymmetry in the domain structure of an iron whisker. This corresponds to 17.2% image contrast, in excellent agreement with the predicted simulated value. A contrast to noise ratio of 27 is achieved at 5 ms acquisition time per pixel.

Froemter, Robert; Hankemeier, Sebastian; Oepen, Hans Peter [Institut fuer Angewandte Physik, Universitaet Hamburg, Jungiusstr. 11, 20355 Hamburg (Germany); Kirschner, Juergen [Max-Planck-Institut fuer Mikrostrukturphysik, Weinberg 2, 06120 Halle (Germany)

2011-03-15T23:59:59.000Z

222

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

Science Conference Proceedings (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

223

SURFACE-MODIFIED FERRITIC INTERCONNECT MATERIALS FOR SOLID OXIDE FUEL CELLS  

DOE Green Energy (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

224

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

Science Conference Proceedings (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

225

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

SciTech Connect

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

226

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

Science Conference Proceedings (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

227

The Nature of the Distinctive Microscopic Features in R5(SixGe1-x)4 Magnetic Refrigeration Materials  

Science Conference Proceedings (OSTI)

Magnetic refrigeration is a promising technology that offers a potential for high energy efficiency. The giant magnetocaloric effect of the R{sub 5}(Si{sub x}, Ge{sub 1-x}){sub 4} alloys (where R=rare-earth and O {le} x {le} 1), which was discovered in 1997, make them perfect candidates for magnetic refrigeration applications. In this study the microstructures of Gd{sub 5}(Si{sub x}Ge{sub 1-x}){sub 4} alloys have been characterized using electron microscopy techniques, with the focus being on distinctive linear features first examined in 1999. These linear features have been observed in R{sub 5}(Si{sub x}, Ge{sub 1-x}){sub 4} alloys prepared from different rare-earths (Gd, Tb, Dy and Er) with different crystal structures (Gd{sub 5}Si{sub 4}-type orthorhombic, monoclinic and Gd{sub 5}Ge{sub 4}-type orthorhombic). Systematic scanning electron microscope studies revealed that these linear features are actually thin-plates, which grow along specific directions in the matrix material. The crystal structure of the thin-plates has been determined as hexagonal with lattice parameters a=b=8.53 {angstrom} and c=6.40 {angstrom} using selected area diffraction (SAD). Energy dispersive spectroscopy analysis, carried out in both scanning and transmission electron microscopes, showed that the features have a composition approximating to R{sub 5}(Si{sub x},Ge{sub 1-x}){sub 3}.phase. Orientation relationship between the matrix and the thin-plates has been calculated as [- 1010](1-211){sub p}//[010](10-2){sub m}. The growth direction of the thin plates are calculated as (22 0 19) and (-22 0 19) by applying the Ag approach of Zhang and Purdy to the SAD patterns of this system. High Resolution TEM images of the Gd{sub 5}Ge{sub 4} were used to study the crystallographic relationship. A terrace-ledge structure was observed at the interface and a 7{sup o} rotation of the reciprocal lattices with respect to each other, consistent with the determined orientation relationship, was noted. Both observations are consistent with the stated hypothesis that the growth direction of the thin-plates is parallel to an invariant line direction. Based on the terrace-ledge structure of the thin-plate interface a displacive-diffusional growth mechanism has been proposed to explain the rapid formation of the R{sub 5}(Si{sub x},Ge{sub 1-x}){sub 3} plates.

Ozan Ugurlu

2006-05-01T23:59:59.000Z

228

Electronic and Magnetic Materials  

Science Conference Proceedings (OSTI)

Oct 27, 2009... by using a planetary ball mill, isostatic cold pressing (148 MPa) and .... power generation schemes such as wind, hydro and tidal power.

229

Soft Magnetic Materials  

Science Conference Proceedings (OSTI)

Mar 1, 2011 ... Recent activity to improve the sustainability of our energy use has resulted in increased awareness of the impact of energy efficiency on the...

230

Electronic and Magnetic Materials  

Science Conference Proceedings (OSTI)

Oct 9, 2012 ... Experimental results obtained using optical interference measurements are ... of electromagnetic interference and reduction of radar signatures.

231

Electronic and Magnetic Materials  

Science Conference Proceedings (OSTI)

Oct 19, 2010 ... It is found that PZT in acetic acid with 2.0 vol% water(? = 50.2 mV) and CFO in acetylacetone-ethanol (1:1 volume ratio, ? = 36.3 mV) were the...

232

Magnetic Materials (MM)  

NLE Websites -- All DOE Office Websites (Extended Search)

Safety and Training Divisions APS Engineering Support Division AES Groups Accelerator Systems Division ASD Groups X-ray Science Division XSD Groups Industry Argonne Home ...

233

Electronics and Magnetic Materials.  

Science Conference Proceedings (OSTI)

Energy Landscape in Frustrated Systems: Cation Hopping and Relaxation in Pyrochlores ... Lead-free Piezoelectric Films for Transducer Applications.

234

Magnetic Materials Committee  

Science Conference Proceedings (OSTI)

The rare earth metals are fundamental to renewable energy technologies; with applications in electric vehicles, energy efficient batteries and the solar panel...

235

Frequency Selective Surfaces as Near Infrared Electro-Magnetic Filters for Thermophotovoltaic Spectral Control  

DOE Green Energy (OSTI)

Frequency selective surfaces (FSS) effectively filter electromagnetic radiation in the microwave band (1mm to 100mm). Interest exists in extending this technology to the near infrared (1 {micro}m to 10 {micro}m) for use as a filter of thermal radiation in thermophotovoltaic (TPV) direct energy conversion. This paper assesses the ability of FSS to meet the strict spectral performance requirements of a TPV system. Inherent parasitic absorption, which is the result of the induced currents in the FSS metallization, is identified as a significant obstacle to achieving high spectral performance.

Ryan T. Kristensen; John F. Beausang; David M. DePoy

2003-12-01T23:59:59.000Z

236

Frequency Selective Surfaces as Near Infrared Electro-Magnetic Filters for Thermophotovoltaic Spectral Control  

DOE Green Energy (OSTI)

Frequency selective surfaces (FSS) effectively filter electromagnetic radiation in the microwave band (1 mm to 100 mm). Interest exists in extending this technology to the near infrared (1 {micro}m to 10 {micro}m) for use as a filter of thermal radiation in thermophotovoltaic (TPV) direct energy conversion. This paper assesses the ability of FSS to meet the strict spectral performance requirements of a TPV system. Inherent parasitic absorption, which is the result of the induced currents in the FSS metallization, is identified as a significant obstacle to achieving high spectral performance.

RF Kristensen; JF Beausang; DM DePoy

2004-06-28T23:59:59.000Z

237

MAGNETIC NEUTRON SCATTERING  

SciTech Connect

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

238

Magnetic Properties through Quantum, Statistics, and Modeling  

Science Conference Proceedings (OSTI)

About this Abstract. Meeting, Materials Science & Technology 2009. Symposium, Magnetic Materials: Structure, Thermodynamics, and Properties. Presentation...

239

Regenerator for Magnetic Refrigerants  

Ames Laboratory researchers have developed a new magnetic material that can be used at low temperatures (sub liquid hydrogen) for magnetic refrigerators.

240

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

SciTech Connect

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

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

Standard for Communicating Waste Characterization and DOT Hazard Classification Requirements for Low Specific Activity Materials and Surface Contaminated Objects  

Energy.gov (U.S. Department of Energy (DOE)) Indexed Site

STD-5507-2013 STD-5507-2013 February 2013 DOE STANDARD Standard for Communicating Waste Characterization and DOT Hazard Classification Requirements for Low Specific Activity Materials and Surface Contaminated Objects [This Standard describes acceptable, but not mandatory means for complying with requirements. Standards are not requirements documents and are not to be construed as requirements in any audit or appraisal for compliance with associated rule or directives.] U.S. Department of Energy SAFT Washington, D.C. 20585 Distribution Statement: A. Approved for public release; distribution is unlimited This document has been reproduced directly from the best available copy. Available to DOE and DOE contractors from ES&H Technical Information Services,

242

About excitation of surface plasma waves by elliptical relativistic electron beam in a magnetized dusty plasma column with elliptical cross section  

Science Conference Proceedings (OSTI)

The surface plasma waves in a magnetized dusty plasma elliptical cylinder driven by elliptic relativistic electron beam propagating inside the elliptical cylinder are studied. The dispersion relation of surface plasma waves has been retrieved from the derived dispersion relation by considering that the beam is absent and there is no dust in the plasma cylinder. Mathematically, it is shown that the beam can interact with the surface plasma waves via Cerenkov interaction and fast cyclotron interaction. The growth rate and phase velocity in every cases are obtained. Finally, the numerical results and graphs are presented.

Abdoli-Arani, A.; Jazi, B. [Department of Physics, University of Kashan, Kashan (Iran, Islamic Republic of)

2012-05-15T23:59:59.000Z

243

About - Materials Technology @ TMS  

Science Conference Proceedings (OSTI)

Administrative & Policy Manual. Scroll up. Scroll down. Technical Divisions Home TMS Committees Home Electronic, Magnetic & Photonic Materials...

244

Breaking symmetries in ordered materials : spin polarized light transport in magnetized noncentrosymmetric 1D photonic crystals, and photonic gaps and fabrication of quasiperiodic structured materials from interference lithography  

E-Print Network (OSTI)

Effects of breaking various symmetries on optical properties in ordered materials have been studied. Photonic crystals lacking space-inversion and time-reversal symmetries were shown to display nonreciprocal dispersion ...

Bita, Ion

2006-01-01T23:59:59.000Z

245

Material Shielding of Power Frequency Magnetic Fields: Research and Testing Results from the EPRI Power Delivery Center -- Lenox  

Science Conference Proceedings (OSTI)

Magnetic fields from power lines and other electrical facilities can interfere with sensitive electronic equipment such as computers, electron microscopes, medical diagnostic and monitoring equipment, and air traffic control displays. Shields can be designed to reduce the magnetic field strength in the areas of interest, but attention must be given to certain aspects of shield design. This report deals with three aspects of practical shield construction: flat sheet dimensions, joining sheets, and thin co...

1998-06-29T23:59:59.000Z

246

Learning About Magnets!  

NLE Websites -- All DOE Office Websites (Extended Search)

the National High Magnetic Field Laboratory Learning About Name A magnet is a material or object that creates a magnetic fi eld. This fi eld is invisible, but it creates a force...

247

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

DOE Green Energy (OSTI)

This work reports the surface stability of the high voltage Li ion cathode LiMn{sub 2x}Ni{sub x}O{sub 4?} (x = 0.5, 0.45) by comparing thin film and powder composite electrodes after cycling using X-ray photoelectron spectroscopy. The thin film electrodes offer the ability to probe the surface of the material without the need of a conductive agent and polymer binder typically used in composite electrodes. The results suggest that neither oxidation of PF{sub 6} to POF{sub 3} nor the decomposition of ethylene carbonate or dimethylene carbonate occurs on the surface of the spinel material. These results confirm the enhanced cycling stability and rate capability associated with the high voltage spinel material and suggests that the SEI layer forms due to the reaction of electrochemically inactive components in composite electrodes with the electrolyte.

Carroll, Kyler J.; Yang, Ming-Che; Veith, G. M.; Dudney, N. J.; Meng, Ying Shirley

2012-01-01T23:59:59.000Z

248

Tunable Magnetic Regenerator/Refrigerant  

Magnetic regenerators utilize the magnetocaloric effect--the ability of a magnetic field to reduce the magnetic part of a solid materials entropy, generating heat, and then removing the magnetic field, permitting the reduction of temperature with the ...

249

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

250

PHASE RETRIEVAL, SYMMETRIZATION RULE AND TRANSPORT OF INTENSITY EQUATION IN APPLICATION TO INDUCTION MAPPING OF MAGNETIC MATERIALS.  

SciTech Connect

Recent progress in the field of noninterferometric phase retrieval brings the ordinary Fresnel microscopy to a new quantitative level, suitable for recovering both the amplitude and phase of the object, based on image intensity measurements of the object. We show that this is sufficient for in-plane component mapping of magnetic induction for small magnetic elements with known geometry ranging from micro- to few nanometers size. In present paper we re-examine some conservation principles used for the transport-of-intensity (TIE) equation derived by Teaque for application to phase retrieval in light and X-ray optics. In particular, we prove that the intensity conservation law should be replaced in general case with the energy-flow conservation law. This law describes the amplitude-phase balance of the partially coherent beam on its propagation along the optical path, valid both for light and electron optics. This substitution has at least two important fundamental consequences.

VOLKOV,V.V.; ZHU,Y.

2002-08-04T23:59:59.000Z

251

Experiment #7: Magnetic Deflection of Beta Rays  

NLE Websites -- All DOE Office Websites (Extended Search)

of magnetism. Materials Geiger counter Wooden block (to hold the source) Aluminum shield with hole (for Geiger counter) Two cow magnets Magnet holders Sr-90 (beta source)...

252

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

E-Print Network (OSTI)

??Superconductivity, charge- and spin-density waves are collective electronic phenomena that originate from electron-electron and electron-phonon interactions, and the concept of Fermi surface competition between these (more)

Zocco, Diego Andrs

2011-01-01T23:59:59.000Z

253

Permanent Magnets for Energy Applications  

Science Conference Proceedings (OSTI)

Mar 13, 2012 ... Magnetic Materials for Energy Applications II: Permanent Magnets for ... to 500% in the last 12 months, the most unstable being the price of Dy.

254

Magnetism Highlights| Neutron Science | ORNL  

NLE Websites -- All DOE Office Websites (Extended Search)

Magnetism Magnetism SHARE Magnetism Highlights 1-5 of 5 Results ARCS maps collaborative magnetic spin behavior in iron telluride December 01, 2011 - Researchers have long thought that magnetism and superconductivity are mutually exclusive. The former typically involves localized atomic electrons. The latter requires freely propagating, itinerant electrons. Unexpected Magnetic Excitations in Doped Insulator Surprise Researchers October 01, 2011 - When doping a disordered magnetic insulator material with atoms of a nonmagnetic material, the conventional wisdom is that the magnetic interactions between the magnetic ions in the material will be weakened. Neutron Analysis Reveals Unique Atomic-Scale Behavior of "Cobalt Blue" September 01, 2011 - Neutron scattering studies of "cobalt blue," a

255

Ultra-high speed permanent magnet axial gap alternator with multiple stators  

DOE Patents (OSTI)

An ultra-high speed, axial gap alternator that can provide an output to a plurality of loads, the alternator providing magnetic isolation such that operating conditions in one load will not affect operating conditions of another load. This improved alternator uses a rotor member disposed between a pair of stator members, with magnets disposed in each of the rotor member surfaces facing the stator members. The magnets in one surface of the rotor member, which alternate in polarity, are isolated from the magnets in the other surface of the rotor member by a disk of magnetic material disposed between the two sets of magents. In the preferred embodiment, this disk of magnetic material is laminated between two layers of non-magnetic material that support the magnets, and the magnetic material has a peripheral rim that extends to both surfaces of the rotor member to enhance the structural integrity. The stator members are substantially conventional in construction in that equally-spaced and radially-oriented slots are provided, and winding members are laid in these slots. A unit with multiple rotor members and stator members is also described.

Hawsey, Robert A. (Oak Ridge, TN); Bailey, J. Milton (Knoxville, TN)

1991-01-01T23:59:59.000Z

256

RESRAD-RECYCLE : a computer model for analyzing radiation exposures resulting from recycling radioactively contaminated scrap metals or reusing ratioactively surface-contaminated materials and equipment.  

Science Conference Proceedings (OSTI)

RESRAD-RECYCLE is a computer code designed by Argonne National Laboratory (ANL) to be used in making decisions about the disposition of radioactively contaminated materials and scrap metals. It implements a pathway analysis methodology to evaluate potential radiation exposures resulting from the recycling of contaminated scrap metals and the reuse of surface-contaminated materials and equipment. For modeling purposes, it divides the entire metal recycling process into six steps: (1) scrap delivery, (2) scrap melting, (3) ingot delivery, (4) product fabrication, (5) product distribution, and (6) use of finished product. RESRAD-RECYCLE considers the reuse of surface-contaminated materials in their original forms. It contains representative exposure scenarios for each recycling step and the reuse process; users can also specify scenarios if desired. The model calculates individual and collective population doses for workers involved in the recycling process and for the public using the finished products. The results are then used to derive clearance levels for the contaminated materials on the basis of input dose restrictions. The model accounts for radiological decay and ingrowth, dilution and partitioning during melting, and distribution of refined metal in the various finished products, as well as the varying densities and geometries of the radiation sources during the recycling process. A complete material balance in terms of mass and radioactivity during the recycling process can also be implemented. In an international validation study, the radiation doses calculated by RESRAD-RECYCLE were shown to agree fairly well with actual measurement data.

Cheng, J. J.; Kassas, B.; Yu, C.; Arnish, J. J.; LePoire, D.; Chen, S.-Y.; Williams, W. A.; Wallo, A.; Peterson, H.; Environmental Assessment; DOE; Univ. of Texas

2004-11-01T23:59:59.000Z

257

Predictive Capability for Strongly Correlated Systems: Mott Transition in MnO, Multielectron Magnetic Moments, and Dynamics Effects in Correlated Materials  

SciTech Connect

There are classes of materials that are important to DOE and to the science and technology community, generically referred to as strongly correlated electron systems (SCES), which have proven very difficult to understand and to simulate in a material-specific manner. These range from actinides, which are central to the DOE mission, to transition metal oxides, which include the most promising components of new spin electronics applications as well as the high temperature superconductors, to intermetallic compounds whose heavy fermion characteristics and quantum critical behavior has given rise to some of the most active areas in condensed matter theory. The objective of the CMSN cooperative research team was to focus on the application of these new methodologies to the specific issue of Mott transitions, multi-electron magnetic moments, and dynamical properties correlated materials. Working towards this goal, the W&M team extended its first-principles phaseless auxiliary-field quantum Monte Carlo (AFQMC) method to accurately calculate structural phase transitions and excited states.

Krakauer, Henry; Zhang, Shiwei

2013-02-21T23:59:59.000Z

258

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

259

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

SciTech Connect

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

260

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

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

Fluctuating surface currents: An algorithm for efficient prediction of Casimir interactions among arbitrary materials in arbitrary geometries  

E-Print Network (OSTI)

This paper presents a method for the efficient numerical computation of Casimir interactions between objects of arbitrary geometries, composed of materials with arbitrary frequency-dependent electrical properties. Our ...

Reid, M. T. Homer

262

Author manuscript, published in "IEEE Conference on Electromagnetic Field Computation (CEFC), Seoul: Korea, Republic of (2004)" Maximization of No-Load Flux Density in Surface Mounted Permanent Magnet Motors  

E-Print Network (OSTI)

AbstractBy using the analytical equations of the no-load flux density obtained with a two-dimensional model (2D) in polar coordinates, the authors proposed to interpolate a new analytical expression of the optimal thickness of the magnet which make it possible to maximize the no-load flux density in the air-gap. The interpolation function of the magnet optimal thickness could be utilized for surface mounted permanent magnet motors having a direction of parallel or radial magnetization [1]. I.

Frdric Dubas; Christophe Espanet; Abdellatif Miraoui

2008-01-01T23:59:59.000Z

263

Magnetism in low dimensionality.  

SciTech Connect

The collective creativity of those working in the field of surface magnetism has stimulated an impressive range of advances. Once wary, theorists are now eager to enter the field. The present article attempts to take a snapshot of where the field has been, with an eye to the more speculative issue of where it is going. Selective examples are used to highlight three general areas of interest (1) characterization techniques, (2) materials properties, and (3) theoretical/simulational advances. Emerging directions are identified and discussed, including laterally confined nanomagnetism and spintronics.

Bader, S. D.; Materials Science Division

2002-03-10T23:59:59.000Z

264

Theoretical studies of surface reactions on metals and electronic materials. Progress report, October 1, 1990--January 31, 1993  

DOE Green Energy (OSTI)

Studies of a variety of adsorbates on Ni have been completed; adsorption energies were determined for CH, CH{sub 2}, CH{sub 3}, H, NH{sub 3}, H{sub 2}O, and C{sub 6}H{sub 6} on Ni(111). A refined calculation of the reaction of methane with Ni was completed. Other studies included H{sub 2} and SiH{sub 4} adsorption/decomposition on Si surfaces, Si-Si dimer bond length, activity energy barriers for reaction of CH{sub 4}and CH{sub 3}F with Si(111). Studies were begun on deposition of C on Ni(111). New directions were explored for reaction of methane with transition metal surfaces; work was completed for a Ni(111) surface containing a substitutional iron atom. Twenty abstracts of papers are presented.

Whitten, J.L.

1993-01-31T23:59:59.000Z

265

Materials Technology @ TMS  

Science Conference Proceedings (OSTI)

Dec 17, 2009 ... Electronic, Magnetic & Photonic Materials .... will support the development of low- cost batteries for electric and plug-in hybrid electric vehicles.

266

Surface Integrity  

Science Conference Proceedings (OSTI)

...inclusions introduced Plastically deformed debris as a result of grinding Voids, pits, burrs, or foreign material inclusions in surface Metallurgical Transformation of phases Grain size and distribution Precipitate size and distribution Foreign inclusions in material Twinning Recrystallization...

267

Minimum Magnetic Energy Theorem  

E-Print Network (OSTI)

The Thomson's Theorem states that static charge distributions in conductors show up at the conducting surfaces in an equipotential configuration, so that the electrostatic energy is a minimum. In this work we study an analogue statement for magnetic systems: in a given set of conductors, the stored magnetic field energy reaches the minimum value for superficial current distributions so that the magnetic vector potential is tangent to the conductors surfaces. This is the counterpart of Thomson's theorem for the magnetic field.

Fiolhais, M C N

2008-01-01T23:59:59.000Z

268

Magnetic Filtration Process, Magnetic Filtering Material, and ...  

Description Produced water or wastewater from coal-methane facilities and other industries contains a complex mixture of contaminants, such as ...

269

Magnetic Filtration Process, Magnetic Filtering Material, and ...  

them unattractive to coal-methane operations. Desalination, ion exchange, and osmosis techniques incur increased energy costs due to high temperature and high

270

Materials Reliability Program: Technical Basis for Primary Water Stress Corrosion Cracking Mitigation by Surface Stress Improvement (MRP-267, Revision 1)  

Science Conference Proceedings (OSTI)

During the past two decades, stress corrosion cracking (SCC) has become the most relevant phenomenon affecting nuclear plant availability and plant lifetime management. SCC can lead to increased costs for operation, maintenance, assessment, repair, and replacement of boiling water reactor (BWR) and pressurized water reactor (PWR) components. Alloy 600 and 82/182 materials, which are widely used in PWR systems, are susceptible to primary water stress corrosion cracking (PWSCC). PWSCC has been reported in ...

2012-07-31T23:59:59.000Z

271

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.

1992-12-31T23:59:59.000Z

272

Effects of a range of machined and ground surface finishes on the simulated reactor helium corrosion of several candidate structural materials. [Inconel MA 754  

SciTech Connect

This report discusses the corrosion behavior of several candidate reactor structural alloys in a simulated advanced high-temperature gas-cooled reactor (HTGR) environment over a range of lathe-machined and centerless-ground surface finishes. The helium environment contained 50 Pa H/sub 2//5 Pa CO/5 Pa CH/sub 4//<0.05 Pa H/sub 2/O (500 ..mu..atm H/sub 2//50 ..mu..atm CO/50 ..mu..atm CH/sub 4//<0.5 ..mu..atm H/sub 2/O) at 900/sup 0/C for a total exposure of 3000 h. The test alloys included two vacuum-cast superalloys (IN 100 and IN 713LC); a centrifugally cast austenitic alloy (HK 40); three wrought high-temperature alloys (Alloy 800H, Hastelloy X, and Inconel 617); and a nickel-base oxide-dispersion-strengthened alloy (Inconel MA 754). Surface finish variations did not affect the simulated advanced-HTGR corrosion behavior of these materials. Under these conditions, the availability of reactant gaseous impurities controls the kinetics of the observed gas-metal interactions. Variations in the near-surface activities and mobilities of reactive solute elements, such as chromium, which might be expected to be affected by changes in surface finish, do not seem to greatly influence corrosion in this simulated advanced HTGR environment. 18 figures, 4 tables.

Thompson, L.D.

1981-02-01T23:59:59.000Z

273

Optimization of the Mechanical Alloying Process of Soft Magnetic Fe ...  

Science Conference Proceedings (OSTI)

Symposium, Magnetic Materials for Energy Applications -III. Presentation Title ... Advances in Rare-earth Free Permanent Magnets Anisotropic Curie...

274

Modeling of Magnetic and Structural Phase Transformations in Co ...  

Science Conference Proceedings (OSTI)

Symposium, Magnetic Materials for Energy Applications -III. Presentation Title, Modeling ... Advances in Rare-earth Free Permanent Magnets Anisotropic Curie

275

Structural Materials - Characterization  

Science Conference Proceedings (OSTI)

Mar 14, 2012 ... Cr, are important structural materials for use in advanced nuclear ... holds promise for grain boundary engineering of surface and near-surface ... nuclear structural material Alloy 690 to illustrate the effects of shield gas, travel...

276

shared session with Advanced Materials for Power Electronics ...  

Science Conference Proceedings (OSTI)

Analysis of Soft Magnetic Materials for Energy Applications: Samuel Kernion1; ... The world-wide market for magnetic materials is anticipated to grow to US$33...

277

Iver Anderson, Division of Materials Sciences and Engineering...  

Energy.gov (U.S. Department of Energy (DOE)) Indexed Site

Kobe, Jozef Stefan Institut, Rare Earth Magnets in Europe Kazuhiro Hono, Magnetic Materials Center Managing Director, NIMS, Research Trends on Rare Earth Materials in Japan...

278

Preparation of anisotropic Nd(Fe,Mo){sub 12}N{sub 1.0} magnetic materials by strip casting technique and direct nitrogenation for the strips  

SciTech Connect

The Nd(Fe,Mo){sub 12}-type alloys are prepared by strip casting technique, and direct nitrogenation of the strips without precrushing is executed in this paper. It is found that 6 h annealing treatment at 1050 deg. C for the strips is enough to obtain the single-phase Nd(Fe,Mo){sub 12} compounds. The strips can be directly nitrogenated at 620 deg. C to obtain interstitial Nd(Fe,Mo){sub 12}N{sub 1.0} materials, and a spontaneous pulverization phenomenon in the strips induced by nitrogenation is found. The results indicate that the nitrogenation process of the strips can be used to prepare Nd(Fe,Mo){sub 12}N{sub 1.0} interstitial nitrides and pulverize the casted strips into fine particles simultaneously. Base on this, we propose a new technical route of preparing Nd(Fe,Mo){sub 12}N{sub X} magnetic powders without precrushing and obtain anisotropic NdFe{sub 10.5}Mo{sub 1.5}N{sub 1.0} powders with a remanence of B{sub r} = 1.08 T, a coercivity of {sub i}H{sub c} = 400 kA/m, and a maximum energy product of (BH){sub max} = 144 kJ/m{sup 3}.

Han Jingzhi; Liu Shunquan; Xing Meiying; Lin Zhong; Kong Xiangpeng; Wang Changsheng; Du Honglin; Yang Yingchang [School of Physics, Peking University, Beijing 100871 (China); Yang Jinbo [School of Physics, Peking University, Beijing 100871 (China); State Key Laboratory for Artificial Microstructure and Mesoscopic Physics, School of Physics, Peking University, Beijing 100871 (China)

2011-04-01T23:59:59.000Z

279

Condensed Matter Physics & Materials Science Department  

NLE Websites -- All DOE Office Websites (Extended Search)

is focused on the Magneto Optical Imaging of magnetic field distribution in superconductors and magnetic materials. How to Contact Us Our Research Characterization...

280

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

SciTech Connect

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

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

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

SciTech Connect

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

282

EL Program: Sustainable Engineered Materials  

Science Conference Proceedings (OSTI)

... surface damage, electrical aging, and dispersion of ... power industry and utilities, construction and infrastructure materials specifiers ...

2013-01-02T23:59:59.000Z

283

BEPC-II Magnet Project | Superconducting Magnet Division  

NLE Websites -- All DOE Office Websites (Extended Search)

BEPC-II Magnet Project BEPC-II Magnet Project Project Overview The BEPC-II magnets are Interaction Region magnets to be used as part of an upgrade to the Beijing Electron Positron Collider. Two magnets will be produced, both of which will be inserted within the solenoidal detector at one of the collision points. Since the best use of the quadrupole focusing in this case requires placing the magnet as close to the collision point as possible, these magnets will be used within the magnetic field of the detector. This constrains the materials that can be used for construction to only non-magnetic materials. It also places severe demands on the structure of the magnet and it's holding supports due to the reaction forces between the solenoid and the magnet. To create the coil pattern for the final magnet, the coils will be

284

Condensed Matter and Materials Physics | U.S. DOE Office of Science (SC)  

Office of Science (SC) Website

Condensed Matter and Materials Physics Condensed Matter and Materials Physics Materials Sciences and Engineering (MSE) Division MSE Home About Research Areas Energy Frontier Research Centers (EFRCs) DOE Energy Innovation Hubs BES Funding Opportunities The Computational Materials and Chemical Sciences Network (CMCSN) Theoretical Condensed Matter Physics Scientific Highlights Reports and Activities Principal Investigators' Meetings BES Home Research Areas Condensed Matter and Materials Physics Print Text Size: A A A RSS Feeds FeedbackShare Page Research is supported to understand, design, and control materials properties and function. These goals are accomplished through studies of the relationship of materials structures to their electrical, optical, magnetic, surface reactivity, and mechanical properties and of the way in

285

Magnetic Materials - Programmaster.org  

Science Conference Proceedings (OSTI)

Thursday 8:30 AM March 7, 2013. Room: 205. Location: Henry B. Gonzalez Convention Center Session Chair: Su-Huai Wei, NREL; Lin-Wang Wang, LBNL...

286

Advanced Magnetic and Quantum Materials  

Science Conference Proceedings (OSTI)

... electron spectroscopy (CMA), Low temperature Omicron STM/AFM, LEED, RHEED, 3 sputter, e-beam, and effusion sources, ion mill, plasma source ...

2011-12-15T23:59:59.000Z

287

Rare Earth and Magnetic Materials  

Science Conference Proceedings (OSTI)

Magnetoresistance Effect Using Co Based Full Heusler Electrodes: Nobuki ... Here we report giant TMR observation at room temperature (RT) for the MTJ using...

288

Magnetic Materials for Energy Applications  

Science Conference Proceedings (OSTI)

Paul R. Ohodnicki, National Energy Technology Laboratory ... the largest electricity consumption in the domestic market is related to refrigeration and ... First to Second Order Magnetocaloric Transition: on Correct Analysis of Experimental Data.

289

Metallurgical Synthesis of Extraterrestrial Permanent Magnet ...  

Science Conference Proceedings (OSTI)

Symposium, Magnetic Materials for Energy Applications IV ... Fe-rich FeSiBPCu Nano-crystalline Soft Magnetic Alloys Contributable To Energy-saving.

290

Excitation of surface plasma waves by a density-modulated electron beam in a magnetized plasma cylinder  

Science Conference Proceedings (OSTI)

A density-modulated electron beam propagating through a plasma cylinder excites surface plasma waves (SPWs) via Cerenkov and fast cyclotron interaction. A nonlocal theory of this process has been developed. Numerical calculations of the growth rate and unstable mode frequencies have been carried out for the typical parameters of the SPWs. The growth rate {gamma} (in rad/s) of the unstable wave instability increases with the modulation index {Delta} and has the largest value for {Delta}{approx}1 in addition to when the frequency and wave number of the modulation are comparable to that of the unstable wave. For {Delta}=0, {gamma} turns out to be {approx}6.06x10{sup 9} rad/s for Cerenkov interaction and {approx}5.47x10{sup 9} rad/s for fast cyclotron interaction. The growth rate of the instability increases with the beam density and scales as one-third power of the beam density in Cerenkov interaction and is proportional to the square root of beam density in fast cyclotron interaction. The real part of the frequency of the unstable wave increases as almost the square root of the beam voltage. The results of the theory are applied to explain some of the experimental observations.

Gupta, Ruby [Department of Physics, Swami Shraddhanand College, University of Delhi, Alipur, Delhi 110036 (India); Sharma, Suresh C. [Department of Physics, Maharaja Agrasen Institute of Technology, PSP Area Plot No.-1, Sector-22, Rohini, Delhi 110086 (India); Prakash, Ved [India Meteorological Department, Ministry of Earth Science, Lodi Road, New Delhi 110003 (India)

2010-12-15T23:59:59.000Z

291

Irreversible magnetic switch  

DOE Patents (OSTI)

This invention is comprised of an irreversible magnetic switch containing a ferromagnetic amorphous metal having a predetermined crystallization temperature in its inductor magnetic path. With the incorporation of such material, the magnetic properties after cooling from a high temperature excursion above its crystallization temperature are only a fraction of the original value. The difference is used to provide a safety feature in the magnetic switch.

Karnowsky, M.M.; Yost, F.G.

1991-12-31T23:59:59.000Z

292

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

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

293

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  

DOE Green Energy (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

294

Nanocomposite Magnets: Transformational Nanostructured Permanent Magnets  

SciTech Connect

Broad Funding Opportunity Announcement Project: GE is using nanomaterials technology to develop advanced magnets that contain fewer rare earth materials than their predecessors. Nanomaterials technology involves manipulating matter at the atomic or molecular scale, which can represent a stumbling block for magnets because it is difficult to create a finely grained magnet at that scale. GE is developing bulk magnets with finely tuned structures using iron-based mixtures that contain 80% less rare earth materials than traditional magnets, which will reduce their overall cost. These magnets will enable further commercialization of HEVs, EVs, and wind turbine generators while enhancing U.S. competitiveness in industries that heavily utilize these alternatives to rare earth minerals.

None

2010-10-01T23:59:59.000Z

295

Magnetic refrigeration apparatus with heat pipes  

DOE Patents (OSTI)

A magnetic refrigerator operating in the 4 to 20 K range utilizes heat pipes to transfer heat to and from the magnetic material at the appropriate points during the material's movement. In one embodiment circular disks of magnetic material can be interleaved with the ends of the heat pipes. In another embodiment a mass of magnetic material reciprocatingly moves between the end of the heat pipe or pipes that transmits heat from the object of cooling to the magnetic material and the end of the heat pipe or pipes that transmits heat from the magnetic material to a heat sink.

Barclay, J.A.; Prenger, F.C. Jr.

1985-10-25T23:59:59.000Z

296

Magnetic refrigeration apparatus with heat pipes  

DOE Patents (OSTI)

A magnetic refrigerator operating in the 4 to 20 K range utilizes heat pipes to transfer heat to and from the magnetic material at the appropriate points during the material's movement. In one embodiment circular disks of magnetic material can be interleaved with the ends of the heat pipes. In another embodiment a mass of magnetic material reciprocatingly moves between the end of the heat pipe of pipes that transmits heat from the object of cooling to the magnetic material and the end of the heat pipe or pipes that transmits heat from the magnetic material to a heat sink.

Barclay, John A. (Los Alamos, NM); Prenger, Jr., F. Coyne (Madison, WI)

1987-01-01T23:59:59.000Z

297

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

SciTech Connect

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

298

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

SciTech Connect

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

299

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

SciTech Connect

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

300

Functional Materials and Surface Treatment  

Science Conference Proceedings (OSTI)

The codeposition can be applied to produce an intermetallic-contained layer requiring ... In this work we present results on the state of the hydrophobicity of...

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

Accelerating Insertion of Materials at GE Aviation  

Science Conference Proceedings (OSTI)

Advancing ICME Capability through Industry/University Relationships ... First Principles Modeling of Shape Memory Alloy Magnetic Refrigeration Materials.

302

3D Materials Science 2014: Meeting Registration  

Science Conference Proceedings (OSTI)

Administrative & Policy Manual. Scroll up. Scroll down. Technical Divisions Home TMS Committees Home Electronic, Magnetic & Photonic Materials...

303

Martin-101013 - Argonne National Laboratories, Materials Sicence...  

NLE Websites -- All DOE Office Websites (Extended Search)

Martin-101013 MATERIALS SCIENCE COLLOQUIUM SPEAKER: Ivar Martin Materials Science Division, ANL TITLE: Complex states in metallic magnets DATE: Thursday, Oct. 10, 2013 TIME: 11:00...

304

Characterization of Minerals, Metals and Materials 2014  

Science Conference Proceedings (OSTI)

Jul 15, 2013... carbon, electronic, magnetic and optical materials, energy materials, ... Comparison between Bio-composite Based on Green HDPE/ Brazil...

305

MAXIMIZING MAGNETIC ENERGY STORAGE IN THE SOLAR CORONA  

Science Conference Proceedings (OSTI)

The energy that drives solar eruptive events such as coronal mass ejections (CMEs) almost certainly originates in coronal magnetic fields. Such energy may build up gradually on timescales of days or longer before its sudden release in an eruptive event, and the presence of free magnetic energy capable of rapid release requires nonpotential magnetic fields and associated electric currents. For magnetic energy to power a CME, that energy must be sufficient to open the magnetic field to interplanetary space, to lift the ejecta against solar gravity, and to accelerate the material to speeds of typically several hundred km s{sup -1}. Although CMEs are large-scale structures, many originate from relatively compact active regions on the solar surface-suggesting that magnetic energy storage may be enhanced when it takes place in smaller magnetic structures. This paper builds on our earlier work exploring energy storage in large-scale dipolar and related bipolar magnetic fields. Here we consider two additional cases: quadrupolar fields and concentrated magnetic bipoles intended to simulate active regions. Our models yield stored energies whose excess over that of the corresponding open field state can be greater than 100% of the associated potential field energy; this contrasts with maximum excess energies of only about 20% for dipolar and symmetric bipolar configurations. As in our previous work, energy storage is enhanced when we surround a nonpotential field with a strong overlying potential field that acts to 'hold down' the nonpotential flux as its magnetic energy increases.

Wolfson, Richard; Drake, Christina; Kennedy, Max, E-mail: wolfson@middlebury.edu [Department of Physics, Middlebury College, Middlebury, VT 05753 (United States)

2012-05-01T23:59:59.000Z

306

Surface Analysis  

DOE Green Energy (OSTI)

In the Surface Analysis group, within the National Center for Photovoltaic's Measurements and Characterization Division, we use surface analytical techniques help to determine the chemical, elemental, and molecular composition, and electronic structure of material surfaces and interfaces. The properties of the surface and outer few micrometers of a material often control the electrical, chemical, or mechanical properties of that material--hence, this region is of extreme importance. Our techniques use ions, electrons, and X-ray or ultraviolet photons in high vacuum to probe surfaces and interfaces of a material. We map the elemental and chemical composition of specimens, study impurities and grain boundaries, gather bonding and chemical-state information, measure surface electronic properties, and perform depth profiles to determine doping and elemental distributions. We have analyzed a wide range of materials, including photovoltaics, microelectronics, polymers, and biological specimens. We work collaboratively with you to solve materials- and device-related R&D problems. This sheet describes our major technique capabilities.

Not Available

2006-06-01T23:59:59.000Z

307

Hardfacing material  

SciTech Connect

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

308

Electric Motors and Critical Materials  

NLE Websites -- All DOE Office Websites (Extended Search)

Research Suggestions (Have an idea of how to get there) * Integration of motor, power converter, and speed reducer * Soft magnetic core material with high saturation...

309

Intrinsic Surface Stability in LiMn2-xNixO4-d (x=0.45, 0.5) High Volt-age Spinel Materials for Lithium Ion Batteries  

SciTech Connect

This work reports the surface stability of the high voltage Li ion cathode LiMn2-xNixO4- (x= 0.5, 0.45) by comparing thin film and powder composite electrodes after cycling using X-ray photoelectron spectroscopy. The thin film electrodes offer the ability to probe the surface of the material without the need of a conductive agent and polymer binder typically used in composite electrodes. The results suggest that neither oxidation of PF6 to POF5 nor the decomposition of ethylene carbonate or dimethylene carbonate occurs on the surface of the spinel material. These results confirm the enhanced cycling stability and rate capability associated with the high voltage spinel material and suggests that the SEI layer forms 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

310

Materials/Condensed Matter  

NLE Websites -- All DOE Office Websites (Extended Search)

Materials/Condensed Matter Print Materials/Condensed Matter Print Materials research provides the foundation on which the economic well being of our high-tech society rests. The impact of advanced materials ranges dramatically over every aspect of our modern world from the minutiae of daily life to the grand scale of our national economy. Invariably, however, breakthroughs to new technologies trace their origin both to fundamental research in the basic properties of condensed matter and to applied research aimed at manipulating properties (structural, physical, chemical, electrical, magnetic, optical, etc.). Increasingly, the frontiers of materials research include materials that are "strongly correlated," characterized by strong coupling between a material's electrons with other electrons, magnetism, or the material lattice itself. This coupling often results in novel behavior, such as superconductivity, that may lead to technologically important applications.

311

MRS (monitored retrievable storage) systems study Task G report: The role and functions of surface storage of radioactive material in the federal waste management system  

SciTech Connect

This is one of nine studies undertaken by contractors to the US Department of Energy (DOE), Office of Civilian Radioactive Waste Management (OCRWM), to provide a technical basis for re-evaluating the role of a monitored retrievable storage (MRS) facility. The study investigates the functions that could be performed by surface storage of radioactive material within the federal radioactive waste management system, including enabling acceptance of spent fuel from utility owners, scheduling of waste-preparation processes within the system, enhancement of system operating reliability, and conditioning the thermal (decay heat) characteristics of spent fuel emplaced in a repository. The analysis focuses particularly on the effects of storage capacity and DOE acceptance schedule on power reactors. Figures of merit developed include the storage capacity (in metric tons of uranium (MTU)) required to be added beyond currently estimated maximum spent fuel storage capacities and its associated cost, and the number of years that spent fuel pools would remain open after last discharge (in pool-years) and the cost of this period of operation. 27 refs., 36 figs., 18 tabs.

Wood, T.W.; Short, S.M.; Woodruff, M.G.; Altenhofen, M.K.; MacKay, C.A.

1989-04-01T23:59:59.000Z

312

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.

Crosse, J A

2009-01-01T23:59:59.000Z

313

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

2009-01-20T23:59:59.000Z

314

Chemistry and Physics of Materials Committee - Committee Home ...  

Science Conference Proceedings (OSTI)

The Chemistry and Physics of Materials Committee is part of the Electronic, Magnetic, and Photonic Materials Division; Structural Materials Division. Our Mission:...

315

High Performance Magnets for Energy Efficient Devices  

Science Conference Proceedings (OSTI)

Bonded Magnetocaloric Powders for the Refrigeration Application Coercivity ... Industrial Needs and Applications for Soft Magnetic Materials Industrial...

316

Rare Earth-free Permanent Magnets I  

Science Conference Proceedings (OSTI)

Mar 4, 2013 ... Sponsored by: TMS Electronic, Magnetic, and Photonic Materials Division, TMS: Energy Committee, TMS: Energy Conversion and Storage...

317

Designing Permanent Magnet Machines for Ferrofluid Immersion  

Science Conference Proceedings (OSTI)

Symposium, Magnetic Materials for Energy Applications -III ... associated costs, and reliability, with thermal and dynamic effects requiring adequate clearance.

318

Magnetism Governs Properties of Iron-Based ...  

Science Conference Proceedings (OSTI)

... a group of materials that conduct electricity without resistance at ... theoretical evidence demonstrating how magnetism controls basic aspects of iron ...

2011-04-06T23:59:59.000Z

319

Processing of Soft Magnetic Alloys in High Magnetic Field  

Science Conference Proceedings (OSTI)

... Magnetic Materials for Use in Energy-efficient Distribution Transformers ... Novel Morphology of Highly Efficient Two-phase Ferrite Cores for Power Systems

320

Multiphase and Multicomponent Materials  

Science Conference Proceedings (OSTI)

The microstructure of the adhered material consisted of oxide ligaments ( nanowires, NWs) that served to attach the debris to tool steel surface as revealed by...

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

Cool Magnetic Molecules  

NLE Websites -- All DOE Office Websites (Extended Search)

Cool Magnetic Molecules Cool Magnetic Molecules Cool Magnetic Molecules Print Wednesday, 25 May 2011 00:00 Certain materials are known to heat up or cool down when they are exposed to a changing magnetic field. This is known as the magnetocaloric effect. All magnetic materials exhibit this effect, but in most cases, it is too small to be technologically useful. Recently, however, the search for special molecules with a surprisingly large capacity to keep cool has heated up, driven by environmental and cost considerations as well as by recent improvements in our ability to design, assemble, and probe the structure and chemistry of small molecules. An international collaboration of researchers from Spain, Scotland, and the U.S. has utilized ALS Beamline 11.3.1 (small-molecule crystallography) to characterize the design of such "molecular coolers." The work targets the synthesis of molecular cluster compounds containing many unpaired electrons ("nanomagnets") for applications involving enhanced magnetic refrigeration at very low temperatures.

322

Influence of selected alkoxysilanes on dispersive properties and surface chemistry of titanium dioxide and TiO2-SiO2 composite material  

Science Conference Proceedings (OSTI)

The paper reports on characterisation of titanium dioxide and coprecipitated TiO2-SiO2 composite material functionalised with selected alkoxysilanes. Synthetic composite material was obtained by an emulsion method with cyclohexane ...

Katarzyna Siwi?ska-Stefa?ska, Filip Ciesielczyk, Magdalena Nowacka, Teofil Jesionowski

2012-01-01T23:59:59.000Z

323

Coal liquefaction process streams characterization and evaluation. Characterization of coal-derived materials by field desorption mass spectrometry, two-dimensional nuclear magnetic resonance, supercritical fluid extraction, and supercritical fluid chromatography/mass spectrometry  

SciTech Connect

Under contract from the DOE , and in association with CONSOL Inc., Battelle, Pacific Northwest Laboratory (PNL) evaluated four principal and several complementary techniques for the analysis of non-distillable direct coal liquefaction materials in support of process development. Field desorption mass spectrometry (FDMS) and nuclear magnetic resonance (NMR) spectroscopic methods were examined for potential usefulness as techniques to elucidate the chemical structure of residual (nondistillable) direct coal liquefaction derived materials. Supercritical fluid extraction (SFE) and supercritical fluid chromatography/mass spectrometry (SFC/MS) were evaluated for effectiveness in compound-class separation and identification of residual materials. Liquid chromatography (including microcolumn) separation techniques, gas chromatography/mass spectrometry (GC/MS), mass spectrometry/mass spectrometry (MS/MS), and GC/Fourier transform infrared (FTIR) spectroscopy methods were applied to supercritical fluid extracts. The full report authored by the PNL researchers is presented here. The following assessment briefly highlights the major findings of the project, and evaluates the potential of the methods for application to coal liquefaction materials. These results will be incorporated by CONSOL into a general overview of the application of novel analytical techniques to coal-derived materials at the conclusion of CONSOL`s contract.

Campbell, J.A.; Linehan, J.C.; Robins, W.H. [Battelle Pacific Northwest Lab., Richland, WA (United States)

1992-07-01T23:59:59.000Z

324

Critical Materials Strategy Summary  

Energy.gov (U.S. Department of Energy (DOE)) Indexed Site

diplomacy. As the nation's leading funder of research on the physical sciences, DOE's capabilities with respect to materials research are substantial. Topics identified for priority research attention include rare earth substitutes in magnets, batteries, photovoltaic films and phosphors; environmentally sound mining and materials processing; and recycling. The eight programs and policies address risks, con- straints and opportunities across the supply chain,

325

Critical Materials Strategy Summary  

Energy.gov (U.S. Department of Energy (DOE)) Indexed Site

diplomacy. As the nation's leading funder of research on the physical sciences, DOE's capabilities with respect to materials research are substantial. Topics identified for priority research attention include rare earth substitutes in magnets, batteries, photovoltaic films and phosphors; environmentally sound mining and materials processing; and recycling. The eight programs and policies address risks, con- straints and opportunities across the supply chain,

326

Searching for a link between the presence of chemical spots on the surface of HgMn stars and their weak magnetic fields  

E-Print Network (OSTI)

We present the results of mapping the HgMn star AR Aur using the Doppler Imaging technique for several elements and discuss the obtained distributions in the framework of a magnetic field topology.

Savanov, I S; Gonzlez, J F; Schller, M

2009-01-01T23:59:59.000Z

327

Unlocking the 'True' Structure of Complex Materials using Total ...  

Science Conference Proceedings (OSTI)

... Magnetic Composite Materials X-Ray Studies of Structural Effects Induced by Pulsed (30 Tesla), High Magnetic Fields at the Advanced Photon Source...

328

Novel Material May Demonstrate Long-Sought 'Liquid' ...  

Science Conference Proceedings (OSTI)

... time the material looks like a magnetic liquid, but ... can be thought of as a tiny bar magnet. ... pattern of spins generally uses less energy, says Broholm ...

2013-01-03T23:59:59.000Z

329

SM Home - Argonne National Laboratories, Materials Sicence Division  

NLE Websites -- All DOE Office Websites (Extended Search)

Home Superconductivity and Magnetism This program undertakes experimental and theoretical investigations of novel superconducting and magnetic materials that are important for...

330

X-Ray Scattering Group, Condensed Matter Physics & Materials...  

NLE Websites -- All DOE Office Websites (Extended Search)

highlights Quantum Persistence of Magnetic Excitations in Overdoped High Temperature Superconductors Novel Magnetic Dispersions by Mixing Ir and Cu Materials Today Popular...

331

Metrology For Organic Monolayers On Cobalt Surfaces  

Science Conference Proceedings (OSTI)

... used in: magnetic recording/storage, catalysis, batteries ... Molecule-metal electrode interface crucial ... formation between organic materials and the ...

2013-03-29T23:59:59.000Z

332

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

Science Conference Proceedings (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

333

Low-temperature magnetic refrigerator  

SciTech Connect

The disclosure is directed to a low temperature 4 to 20 K. refrigeration apparatus and method utilizing a ring of magnetic material moving through a magnetic field. Heat exchange is accomplished in and out of the magnetic field to appropriately utilize the device to execute Carnot and Stirling cycles.

Barclay, John A. (Los Alamos, NM)

1985-01-01T23:59:59.000Z

334

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

335

Fast superconducting magnetic field switch  

DOE Patents (OSTI)

The superconducting magnetic switch or fast kicker magnet is employed with an 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 than 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. Magnetic switches and particularly fast kicker magnets are used in the accelerator industry to quickly deflect particle beams into and out of various transport lines, storage rings, dumps, and specifically to differentially route individual bunches of particles from a train of bunches which are injected or ejected from a given ring.

Goren, Y.; Mahale, N.K.

1995-12-31T23:59:59.000Z

336

A Cryogenic RF Material Testing Facility at SLAC  

SciTech Connect

The authors have developed an X-band SRF testing system using a high-Q copper cavity with an interchangeable flat bottom for the testing of different materials. By measuring the Q of the cavity, the system is capable to characterize the quenching magnetic field of the superconducting samples at different power level and temperature, as well as the surface resistivity. This paper presents the most recent development of the system and testing results.

Guo, Jiquan; Martin, David; Tantawi, Sami; Yoneda, Charles; /SLAC

2012-06-22T23:59:59.000Z

337

Cool Magnetic Molecules  

NLE Websites -- All DOE Office Websites (Extended Search)

Cool Magnetic Molecules Print Cool Magnetic Molecules Print Certain materials are known to heat up or cool down when they are exposed to a changing magnetic field. This is known as the magnetocaloric effect. All magnetic materials exhibit this effect, but in most cases, it is too small to be technologically useful. Recently, however, the search for special molecules with a surprisingly large capacity to keep cool has heated up, driven by environmental and cost considerations as well as by recent improvements in our ability to design, assemble, and probe the structure and chemistry of small molecules. An international collaboration of researchers from Spain, Scotland, and the U.S. has utilized ALS Beamline 11.3.1 (small-molecule crystallography) to characterize the design of such "molecular coolers." The work targets the synthesis of molecular cluster compounds containing many unpaired electrons ("nanomagnets") for applications involving enhanced magnetic refrigeration at very low temperatures.

338

Cool Magnetic Molecules  

NLE Websites -- All DOE Office Websites (Extended Search)

Cool Magnetic Molecules Print Cool Magnetic Molecules Print Certain materials are known to heat up or cool down when they are exposed to a changing magnetic field. This is known as the magnetocaloric effect. All magnetic materials exhibit this effect, but in most cases, it is too small to be technologically useful. Recently, however, the search for special molecules with a surprisingly large capacity to keep cool has heated up, driven by environmental and cost considerations as well as by recent improvements in our ability to design, assemble, and probe the structure and chemistry of small molecules. An international collaboration of researchers from Spain, Scotland, and the U.S. has utilized ALS Beamline 11.3.1 (small-molecule crystallography) to characterize the design of such "molecular coolers." The work targets the synthesis of molecular cluster compounds containing many unpaired electrons ("nanomagnets") for applications involving enhanced magnetic refrigeration at very low temperatures.

339

Cool Magnetic Molecules  

NLE Websites -- All DOE Office Websites (Extended Search)

Cool Magnetic Molecules Print Cool Magnetic Molecules Print Certain materials are known to heat up or cool down when they are exposed to a changing magnetic field. This is known as the magnetocaloric effect. All magnetic materials exhibit this effect, but in most cases, it is too small to be technologically useful. Recently, however, the search for special molecules with a surprisingly large capacity to keep cool has heated up, driven by environmental and cost considerations as well as by recent improvements in our ability to design, assemble, and probe the structure and chemistry of small molecules. An international collaboration of researchers from Spain, Scotland, and the U.S. has utilized ALS Beamline 11.3.1 (small-molecule crystallography) to characterize the design of such "molecular coolers." The work targets the synthesis of molecular cluster compounds containing many unpaired electrons ("nanomagnets") for applications involving enhanced magnetic refrigeration at very low temperatures.

340

Cool Magnetic Molecules  

NLE Websites -- All DOE Office Websites (Extended Search)

Cool Magnetic Molecules Print Cool Magnetic Molecules Print Certain materials are known to heat up or cool down when they are exposed to a changing magnetic field. This is known as the magnetocaloric effect. All magnetic materials exhibit this effect, but in most cases, it is too small to be technologically useful. Recently, however, the search for special molecules with a surprisingly large capacity to keep cool has heated up, driven by environmental and cost considerations as well as by recent improvements in our ability to design, assemble, and probe the structure and chemistry of small molecules. An international collaboration of researchers from Spain, Scotland, and the U.S. has utilized ALS Beamline 11.3.1 (small-molecule crystallography) to characterize the design of such "molecular coolers." The work targets the synthesis of molecular cluster compounds containing many unpaired electrons ("nanomagnets") for applications involving enhanced magnetic refrigeration at very low temperatures.

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

Cool Magnetic Molecules  

NLE Websites -- All DOE Office Websites (Extended Search)

Cool Magnetic Molecules Print Cool Magnetic Molecules Print Certain materials are known to heat up or cool down when they are exposed to a changing magnetic field. This is known as the magnetocaloric effect. All magnetic materials exhibit this effect, but in most cases, it is too small to be technologically useful. Recently, however, the search for special molecules with a surprisingly large capacity to keep cool has heated up, driven by environmental and cost considerations as well as by recent improvements in our ability to design, assemble, and probe the structure and chemistry of small molecules. An international collaboration of researchers from Spain, Scotland, and the U.S. has utilized ALS Beamline 11.3.1 (small-molecule crystallography) to characterize the design of such "molecular coolers." The work targets the synthesis of molecular cluster compounds containing many unpaired electrons ("nanomagnets") for applications involving enhanced magnetic refrigeration at very low temperatures.

342

Structural, magnetic, and electrochemical studies on lithium insertion materials LiNi{sub 1-x}Co{sub x}O{sub 2} with 0{<=}x{<=}0.25  

Science Conference Proceedings (OSTI)

The structural, magnetic, and electrochemical properties of the LiNi{sub 1-x}Co{sub x}O{sub 2} samples with x= 0, 0.05, 0.1, and 0.25 have been investigated by powder X-ray diffraction analyses, magnetic susceptibility ({chi}) measurements, and electrochemical charge and discharge test in non-aqueous lithium cell. According to the structural analyses using a Rietveld method, the occupancy of the Ni ions in the Li layer was estimated to be below 0.01 for all the samples and was eventually independent of x. The temperature (T) dependence of {chi}{sup -1} obtained with the magnetic field H=10 kOe indicated that all the samples are a Curie-Weiss paramagnet down to {approx}100K. At low T, all the samples entered into a spin-glass-like phase below T{sub f}. The magnitude of T{sub f} was found to decrease almost linearly with x, as in the case for the x dependences of the lattice parameters of a{sub h}- and c{sub h}-axes, Weiss temperature, and effective magnetic moment. It is, therefore, found that the change of the magnetic properties with x is simply explained by a dilution effect due to the increase of the quantity of Co{sup 3+} ions. On the other hand, the electrochemical measurements demonstrated that the irreversible capacity at the initial cycle is drastically decreased by the small amount of Co ions. Furthermore, the discharge capacity (Q{sub dis}) for the x=0.05 and 0.1 samples are larger than that for the x=0 sample; namely, Q{sub dis}=180 mAh g{sup -1} for x=0, Q{sub dis}=217 mAh g{sup -1} for x=0.05, and Q{sub dis}=206 mAh g{sup -1} for x=0.1. Comparing with the past results, the amount of Ni ions in the Li layer is found to play a significant role for determining the magnetic and electrochemical properties of LiNi{sub 1-x}Co{sub x}O{sub 2}. - Graphical Abstract: The inter-relationship between structural, magnetic, and electrochemical properties of the lithium insertion materials LiNi{sub 1-x}Co{sub x}O{sub 2} with 0{<=}x{<=}0.25 were investigated by X-ray diffraction measurements, magnetic susceptibility measurements, and electrochemical charge and discharge test in non-aqueous lithium cell. The magnitude of spin-glass-like transition temperature T{sub f} was found to decrease almost linearly with x, as well as the x dependences of effective magnetic moment, Weiss temperature, and lattice parameters.

Mukai, Kazuhiko, E-mail: e1089@mosk.tytlabs.co.j [Toyota Central Research and Development Laboratories, Inc., 41-1 Yokomichi, Nagakute, Aichi 480-1192 (Japan); Sugiyama, Jun; Aoki, Yoshifumi [Toyota Central Research and Development Laboratories, Inc., 41-1 Yokomichi, Nagakute, Aichi 480-1192 (Japan)

2010-07-15T23:59:59.000Z

343

Soft magnetic rapidly solidified bilayer ribbons for energy applications  

Science Conference Proceedings (OSTI)

Fe-rich FeSiBPCu Nano-crystalline Soft Magnetic Alloys Contributable To Energy -saving Fe and Mn Based Materials for Magnetic Refrigeration First-order...

344

Tailoring of Magnetic Properties and GMI Effect in Thin Amorphous ...  

Science Conference Proceedings (OSTI)

Fabrication of Nanocrystalline Magnetic Materials for Use in Energy-efficient Distribution Transformers Fabrication of ?-Fe16N2 Bulk Magnets by...

345

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

346

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

SciTech Connect

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

347

Laser Detection Of Material Thickness  

NLE Websites -- All DOE Office Websites (Extended Search)

Detection Of Material Thickness Detection Of Material Thickness Laser Detection Of Material Thickness There is provided a method for measuring material thickness. Available for thumbnail of Feynman Center (505) 665-9090 Email Laser Detection Of Material Thickness There is provided a method for measuring material thickness comprising: (a) contacting a surface of a material to be measured with a high intensity short duration laser pulse at a light wavelength which heats the area of contact with the material, thereby creating an acoustical pulse within the material: (b) timing the intervals between deflections in the contacted surface caused by the reverberation of acoustical pulses between the contacted surface and the opposite surface of the material: and (c) determining the thickness of the material by calculating the proportion of

348

Investigating the Ability of a Land Surface Model to Simulate Streamflow with the Accuracy of Hydrological Models: A Case Study Using MOPEX Materials  

Science Conference Proceedings (OSTI)

In the Model Parameter Estimation Experiment (MOPEX) project, after calibration of model parameters, complex rainfallrunoff hydrological models (HMs) simulated streamflow better than land surface models (LSMs), including the SoilWater...

Olga N. Nasonova; Yeugeniy M. Gusev; Yeugeniy E. Kovalev

2009-10-01T23:59:59.000Z

349

GEOCHEMICAL CONTROLS ON NUCLEAR MAGNETIC RESONANCE MEASUREMENTS  

Science Conference Proceedings (OSTI)

Proton nuclear magnetic resonance (NMR) is used in the Earth Sciences as a means of obtaining information about the molecular-scale environment of fluids in porous geological materials. Laboratory experiments were conducted to advance our fundamental understanding of the link between the NMR response and the geochemical properties of geological materials. In the first part of this research project, we studied the impact of both the surface-area-to-volume ratio (S/V) of the pore space and the surface relaxivity on the NMR response of fluids in sand-clay mixtures. This study highlighted the way in which these two parameters control our ability to use NMR measurements to detect and quantify fluid saturation in multiphase saturated systems. The second part of the project was designed to explore the way in which the mineralogic form of iron, as opposed to simply the concentration of iron, affects the surface relaxation rate and, more generally, the NMR response of porous materials. We found that the magnitude of the surface relaxation rate was different for the various iron-oxide minerals because of changes in both the surface-area-to-volume ratio of the pore space, and the surface relaxivity. Of particular significance from this study was the finding of an anomalously large surface relaxivity of magnetite compared to that of the other iron minerals. Differences in the NMR response of iron minerals were seen in column experiments during the reaction of ferrihydrite-coated quartz sand with aqueous Fe(II) solutions to form goethite, lepidocrocite and magnetite; indicating the potential use of NMR as a means of monitoring geochemical reactions. The final part of the research project investigated the impact of heterogeneity, at the pore-scale, on the NMR response. This work highlighted the way in which the geochemistry, by controlling the surface relaxivity, has a significant impact on the link between NMR data and the microgeometry of the pore space.

Rosemary Knight

2008-08-25T23:59:59.000Z

350

Argonne CNM: Materials Synthesis Capabilities  

NLE Websites -- All DOE Office Websites (Extended Search)

Materials Synthesis Facilities Materials Synthesis Facilities Capabilities biosynthesis View larger image. Biosynthesis Methods Peptide and DNA synthesis (E. Rozhkova, Nanobio Interfaces Group) Nanobio hybrid synthesis (T. Rajh, Nanobio Interfaces Group) Hierarchal assembly View larger image. Hierarchical Assembly Bottom-up polymeric and bio-templating as well as lithographically directed self-assembly (S. Darling, Electronic & Magnetic Materials & Devices Group; E. Rozhkova, Nanobio Interfaces Group) Molecular beam epitaxy View high-resolution image. Molecular Beam Epitaxy Complex oxide nanoferroelectric and nanoferromagnetic materials and devices created using a DCA R450D Custom MBE instrument (A. Bhattacharya, Electronic & Magnetic Materials & Devices Group) Nanoparticle synthesis

351

Biomaterial Surfaces II  

Science Conference Proceedings (OSTI)

Biofilm produced by microbes is a structure formed on material surface containing water ... In this work, both dense and porous silica and niobium oxide coatings were ... environments and their surface and interfacial breakdown was examined.

352

Magnetohydrodynamic evolution of magnetic skeletons  

E-Print Network (OSTI)

The heating of the solar corona is likely to be due to reconnection of the highly complex magnetic field that threads throughout its volume. We have run a numerical experiment of an elementary interaction between the magnetic field of two photospheric sources in an overlying field that represents a fundamental building block of the coronal heating process. The key to explaining where, how and how much energy is released during such an interaction is to calculate the resulting evolution of the magnetic skeleton. A skeleton is essentially the web of magnetic flux surfaces (called separatrix surfaces) that separate the coronal volume into topologically distinct parts. For the first time the skeleton of the magnetic field in a 3D numerical MHD experiment is calculated and carefully analysed, as are the ways in which it bifurcates into different topologies. A change in topology normally changes the number of magnetic reconnection sites. In our experiment, the magnetic field evolves through a total of six distinct ...

Haynes, A L; Galsgaard, K; Priest, E R; Haynes, Andrew L.; Parnell, Clare E.; Galsgaard, Klaus; Priest, Eric R.

2007-01-01T23:59:59.000Z

353

Method and apparatus for detecting flaws in conductive material  

Science Conference Proceedings (OSTI)

The present invention uses a magnet in relative motion to a conductive material, and a coil that is stationary with respect to the magnet to measure perturbation or variation in the magnetic field in the presence of an inclusion. The magnet and coil sensor may be on the same side of the conductive material. 18 figs.

Hockey, R.L.; Riechers, D.M.

1998-07-07T23:59:59.000Z

354

Method and apparatus for detecting flaws in conductive material  

DOE Patents (OSTI)

The present invention uses a magnet in relative motion to a conductive material, and a coil that is stationary with respect to the magnet to measure perturbation or variation in the magnetic field in the presence of an inclusion. The magnet and coil sensor may be on the same side of the conductive material.

Hockey, Ronald L. (Richland, WA); Riechers, Douglas M. (Richland, WA)

1998-01-01T23:59:59.000Z

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

Materials Science  

Science Conference Proceedings (OSTI)

Materials Science. Summary: ... Description: Group focus in materials science (inkjet metrology, micro-macro, advanced characterizations). ...

2012-10-02T23:59:59.000Z

357

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 tc 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.

1991-03-13T23:59:59.000Z

358

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.

1992-12-31T23:59:59.000Z

359

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

360

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

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

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

DOE Patents (OSTI)

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

Jiles, D.C.

1991-04-16T23:59:59.000Z

362

Processing and Performance of Materials using Microwaves, Electric ...  

Science Conference Proceedings (OSTI)

Symposium, Rustum Roy Memorial Symposium: Processing and Performance of Materials using Microwaves, Electric and Magnetic Fields, Ultrasound, Lasers,...

363

Virtual Mechanical Testing of Composites: From Materials to ...  

Science Conference Proceedings (OSTI)

First Principles Modeling of Shape Memory Alloy Magnetic Refrigeration Materials ... Different Generations of Gamma Prime Precipitates in a Commercial Nickel...

364

Advanced Materials for High Power, High Temperature, and High ...  

Science Conference Proceedings (OSTI)

Mar 5, 2013 ... Advanced magnetic materials are required for enhanced performance of electrical and thermal power generation, distribution, and conversion...

365

Advanced Materials for Power Electronics, Power Conditioning, and ...  

Science Conference Proceedings (OSTI)

TMS: Energy Conversion and Storage Committee TMS: Magnetic Materials Committee. Organizer(s), Paul Ohodnicki, National Energy Technology Laboratory

366

Advanced Materials for Power Electronics, Power Conditioning, and ...  

Science Conference Proceedings (OSTI)

Sponsorship, TMS: Energy Conversion and Storage Committee TMS: Magnetic Materials Committee. Organizer(s), Paul Ohodnicki, National Energy Technology

367

New Materials and Novel Anisotropies for Rare-Earth-Free ...  

Science Conference Proceedings (OSTI)

... subjected to extremely slow cooling rates occurring over one billion years. ... Challenges of Magnetic Material Development for Vehicle Electrification.

368

Earth materials and earth dynamics  

Science Conference Proceedings (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

369

Magnetically leviated superconducting bearing  

DOE Patents (OSTI)

A magnetically levitated superconducting bearing includes a magnet (2) mounted on a shaft (12) that is rotatable around an axis of rotation and a Type II superconductor (6) supported on a stator (14) in proximity to the magnet (2). The superconductor (6) is positioned so that when it is cooled to its superconducting state in the presence of a magnetic field, it interacts with the magnet (2) to produce an attractive force that levitates the magnet (2) and supports a load on the shaft (12). The interaction between the superconductor (6) and magnet(2) also produces surface screening currents (8) that generate a repulsive force perpendicular to the load. The bearing also has means for maintaining the superconductor at a temperature below its critical temperature (16, 18). The bearing could also be constructed so the magnet (2) is supported on the stator (14) and the superconductor (6) is mounted on the shaft (12). The bearing can be operated by cooling the superconductor (6) to its superconducting state in the presence of a magnetic field.

Weinberger, Bernard R. (Avon, CT); Lynds, Jr., Lahmer (Glastonbury, CT)

1993-01-01T23:59:59.000Z

370

Superconducting Magnets  

NLE Websites -- All DOE Office Websites (Extended Search)

magnet technology has allowed physicists to attain higher energies in circular accelerators. One can obtain higher magnetic fields because there is no resistance in a...

371

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

372

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

SciTech Connect

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

373

Production of Materials with Superior Properties Utilizing ...  

UT-B IDs 200401490, 200501531, 200701867, 200802085, 200902312, 201002455, 201102675 07.2012 Technology Summary Processing materials in a magnetic ...

374

Symposium K: Composites and Hybrid Materials  

Science Conference Proceedings (OSTI)

Aug 3, 2010 ... The Tc was determined by electrical resistivity and magnetization to be ... The introduction of composite materials are welcomed in the market...

375

Vehicle Technologies Office: Materials by Design  

NLE Websites -- All DOE Office Websites (Extended Search)

improve research on a variety of technologies, such as: Magnetics for electric motors Thermoelectric materials for energy recovery Improved catalysts for exhaust...

376

Materials Development for the Traveling Wave Reactor  

Science Conference Proceedings (OSTI)

Symposium, Materials and Fuels for the Current and Advanced Nuclear Reactors ... First-Principles Theory of Magnetism, Crystal Field and Phonon Spectrum of...

377

Superconducting Magnet Division  

NLE Websites -- All DOE Office Websites (Extended Search)

3 - 6/13/06 3 - 6/13/06 Superconducting Magnet Division S&T Committee Program Review June 22-23, 2006 Conference Room A, Bldg. 725, BNL DRAFT AGENDA Thursday, June 22 0830 Executive Session to address the charge S. Aronson (25 min) 0855 Welcome S. Aronson (5 min) 0900 Superconducting Magnet Division Status & M. Harrison (45 + 15 min) Issues - mission statement, core competencies, themes, program, problems, etc. 1000 Themes - Nb3Sn, HTS, Direct wind, Accelerator integration, P. Wanderer (20 + 10 min) rapid cycling Core Competencies 1030 Superconducting Materials A. Ghosh (20 + 5 min) 1055 Break 1110 Magnetic Design R. Gupta (20 + 5 min) 1135 Magnet Construction M. Anerella (20 + 5 min) 1200 Magnet Testing G. Ganetis (20 + 5 min)

378

Fueling of magnetic confinement devices  

DOE Green Energy (OSTI)

A general overview of the fueling of magnetic confinement devices is presented, with particular emphasis on recent experimental results. Various practical fueling mechanisms are considered, such as cold gas inlet (or plasma edge fueling), neutral beam injection, and injection of high speed cryogenic hydrogen pellets. The central role played by charged particle transport and recycle of plasma particles from material surfaces in contact with the plasma is discussed briefly. The various aspects of hydrogen pellet injection are treated in detail, including applications to the production of high purity start-up plasmas for stellarators and other devices, refueling of tokamak plasmas, pellet ablation theory, and the technology and performance characteristics of low and high speed pellet injectors.

Milora, S.L.

1982-04-01T23:59:59.000Z

379

Magnetic field generator  

DOE Patents (OSTI)

A magnetic field generating device provides a useful magnetic field within a specific retgion, while keeping nearby surrounding regions virtually field free. By placing an appropriate current density along a flux line of the source, the stray field effects of the generator may be contained. One current carrying structure may support a truncated cosine distribution, and it may be surrounded by a current structure which follows a flux line that would occur in a full coaxial double cosine distribution. Strong magnetic fields may be generated and contained using superconducting cables to approximate required current surfaces.

Krienin, Frank (Shoreham, NY)

1990-01-01T23:59:59.000Z

380

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

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

Particle Size Dependence on Magnetic Properties of AlNiCo Powders  

Science Conference Proceedings (OSTI)

Symposium, Magnetic Materials for Energy Applications IV ... New generation of electric motors require permanent magnets with better coercivity and magnetic flux. ... Recent Developments in Rare Earth Lean/Free High Energy Magnets.

382

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

383

The solar magnetic field  

E-Print Network (OSTI)

The magnetic field of the Sun is the underlying cause of the many diverse phenomena combined under the heading of solar activity. Here we describe the magnetic field as it threads its way from the bottom of the convection zone, where it is built up by the solar dynamo, to the solar surface, where it manifests itself in the form of sunspots and faculae, and beyond into the outer solar atmosphere and, finally, into the heliosphere. On the way it, transports energy from the surface and the subsurface layers into the solar corona, where it heats the gas and accelerates the solar wind.

Solanki, Sami K; Schssler, Manfred; 10.1088/0034-4885/69/3/R02

2010-01-01T23:59:59.000Z

384

SC e-journals, Materials Science  

Office of Scientific and Technical Information (OSTI)

Materials Science Materials Science Acta Materialia Advanced Composite Materials Advanced Energy Materials Advanced Engineering Materials Advanced Functional Materials Advanced Materials Advanced Powder Technology Advances in Materials Science and Engineering - OAJ Annual Review of Materials Research Applied Composite Materials Applied Mathematical Modelling Applied Mathematics & Computation Applied Physics A Applied Physics B Applied Surface Science Archives of Computational Materials Science and Surface Engineering - OAJ Archives of Materials Science and Engineering - OAJ Carbohydrate Polymers Carbon Catalysis Science & Technology Cellulose Cement and Concrete Research Ceramic Engineering and Science Proceedings Ceramics International Chalcogenide Letters - OAJ Chemical and Petroleum Engineering

385

Coercivity Enhancement in Sintered Nd-Fe-B Magnets Annealed ...  

Science Conference Proceedings (OSTI)

Bonded Magnetocaloric Powders for the Refrigeration Application Coercivity ... Industrial Needs and Applications for Soft Magnetic Materials Industrial...

386

Low Loss, High Power Density Magnetics in Inductor/Transformer ...  

Science Conference Proceedings (OSTI)

The former power requirements motivate high efficiency materials for use in bulk scale inductors and transformers. The magnetic material requirements include...

387

Magnetism and Superconductivity in Ruthenates, Ruthenocuprates, and Other Layered Oxides.  

E-Print Network (OSTI)

??There exist several classes of materials that simultaneously exhibit superconductivity and anomalous magnetic order, where both effects are homogeneous throughout the material. No cohesive explanation (more)

Smylie, Matthew Passmore

2010-01-01T23:59:59.000Z

388

Wave refraction in left-handed materials  

E-Print Network (OSTI)

We examine the response of a plane wave incident on a flat surface of a medium characterized by simultaneously negative electric and magnetic susceptibilities by solving Maxwell's equations explicitly and without making any assumptions on the way. In the literature up to date, it has been assumed that negative refractive materials are necessarily frequency dispersive. We propose an alternative to this assumption by suggesting that the requirement of positive energy density should be relaxed, and discuss the implications of such a proposal. More specifically, we show that once negative energy solutions are accepted, the necessity for frequency dispersion is no longer necessary. Finally, we argue that, for the purposes of discussing negative index materials, the use of group velocity as the physically significant quantity is misleading, and suggest that any discussion involving it should be carefully reconsidered.

Chimonidou, Antonia

2008-01-01T23:59:59.000Z

389

Material Independent Design of Photoluminescent Systems Based ...  

Energy Storage Advanced Materials Material Independent Design of Photoluminescent Systems Based on Alignment of Polar Molecules in Charged Surface Oak Ridge ...

390

Magneto-optical Analysis of Magnetic Microstructures  

Science Conference Proceedings (OSTI)

... Magnetic Materials for Use in Energy-efficient Distribution Transformers ... Novel Morphology of Highly Efficient Two-phase Ferrite Cores for Power Systems

391

Development of MnBi Permanent Magnet  

Science Conference Proceedings (OSTI)

... Magnetic Materials for Use in Energy-efficient Distribution Transformers ... Novel Morphology of Highly Efficient Two-phase Ferrite Cores for Power Systems

392

Electronic and Magnetic Properties of Ni  

Science Conference Proceedings (OSTI)

... Magnetic Materials for Use in Energy-efficient Distribution Transformers ... Novel Morphology of Highly Efficient Two-phase Ferrite Cores for Power Systems

393

Magnetic Refrigeration a 21 - Programmaster.org  

Science Conference Proceedings (OSTI)

Presentation Title, Magnetic Refrigeration a 21st Century Highly Efficient and Green ... Alloy Design and Powder Processing of Mn-Al Based Materials for Rare

394

Tailored Porous Materials  

Science Conference Proceedings (OSTI)

Tailoring of porous materials involves not only chemical synthetic techniques for tailoring microscopic properties such as pore size, pore shape, pore connectivity, and pore surface reactivity, but also materials processing techniques for tailoring the meso- and the macroscopic properties of bulk materials in the form of fibers, thin films and monoliths. These issues are addressed in the context of five specific classes of porous materials: oxide molecular sieves, porous coordination solids, porous carbons, sol-gel derived oxides, and porous heteropolyanion salts. Reviews of these specific areas are preceded by a presentation of background material and review of current theoretical approaches to adsorption phenomena. A concluding section outlines current research needs and opportunities.

BARTON,THOMAS J.; BULL,LUCY M.; KLEMPERER,WALTER G.; LOY,DOUGLAS A.; MCENANEY,BRIAN; MISONO,MAKOTO; MONSON,PETER A.; PEZ,GUIDO; SCHERER,GEORGE W.; VARTULI,JAMES C.; YAGHI,OMAR M.

1999-11-09T23:59:59.000Z

395

NEWTON's Material Science Archive  

NLE Websites -- All DOE Office Websites (Extended Search)

Materials Science Archive: Materials Science Archive: Loading Most Recent Materials Science Questions: Hydrogen Compounds and Heat Conduction Weaving Carbon Nanotubes Metal as Electrical Conductor, Not Thermal Steel Changes with Age PETE, Ultraviolet Light, Benefits Strength of Yarn by Spinning Each Substance Unique Density Alloy versus Constituent Density Knowing When Material is Melted Crystalline Metal Versus Metallic Glass and Conduction Super Glue, Surgery, and Skin Silica Gel Teflon Non-Stick Property Salt Crystal Formation Lubricating Rubber Bands and Elasticity Materials for Venus Probe Crystalline Solids and Lowest Energy Sodium Polycarbonate and Salt Water Early Adhesives Surface Energy and Temperature Separating Polypropylene, Polyester, and Nylon Factors Effecting Polymer Flexibility

396

Advanced Materials  

NLE Websites -- All DOE Office Websites (Extended Search)

Advanced Materials Advanced Materials Availability Technology Express Licensing Active Terahertz Metamaterial Devices Express Licensing Anion-Conducting Polymer, Composition, And...

397

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

398

Magnetic Resonance Facility (Fact Sheet)  

DOE Green Energy (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

399

Materials Characterization | Advanced Materials | ORNL  

NLE Websites -- All DOE Office Websites (Extended Search)

Characterization Nuclear Forensics Scanning Probes Related Research Materials Theory and Simulation Energy Frontier Research Centers Advanced Materials Home | Science &...

400

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

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

Moving Magnet Series with  

E-Print Network (OSTI)

material allows for exceptional flux densi- ties in the air gap. The intense magnetic field strengthV/Degree/Second, +/-10% Current, RMS 2.3 2.4 4.1 3.9 A, Maximum Current, Peak 6 8 20 20 A, Maximum Small Angle Step

Kleinfeld, David

402

Materials Science  

NLE Websites -- All DOE Office Websites (Extended Search)

Materials Science Materials Science Materials Science1354608000000Materials ScienceSome of these resources are LANL-only and will require Remote Access./No/Questions? 667-5809library@lanl.gov Materials Science Some of these resources are LANL-only and will require Remote Access. Key Resources Data Sources Reference Organizations Journals Key Resources CINDAS Materials Property Databases video icon Thermophysical Properties of Matter Database (TPMD) Aerospace Structural Metals Database (ASMD) Damage Tolerant Design Handbook (DTDH) Microelectronics Packaging Materials Database (MPMD) Structural Alloys Handbook (SAH) Proquest Technology Collection Includes the Materials Science collection MRS Online Proceedings Library Papers presented at meetings of the Materials Research Society Data Sources

403

New Materials for Spintronics  

SciTech Connect

One of the critical materials needs for the development of spin electronics is diluted magnetic semiconductors (DMS) which retain their ferromagnetism at and above room temperature. Spin polarization in DMS materials leads to the possibility of spin-polarized current injection into nonmagnetic semiconductor heterostructures. Such transport is of critical importance in the development of devices that utilize spin (e.g. spin-LEDs and spin-FETs). New magnetically-doped semiconducting oxides that show promise because of Curie points which exceed room temperature are currently being investigated in our lab and elsewhere. However, the detailed materials properties and mechanism(s) of magnetism in these systems have been elusive. In this talk, I will present recent results from our laboratory focused on the MBE synthesis and properties of these ferromagnetic oxide semiconductors. This work was funded by the PNNL Nanoscience and Technology Initiative, the US Department of Energy, Office of Science, Office of Basic Energy Sciences, Division of Materials Science and Engineering Physics, and the DARPA Spins in Semiconductors (SPINS) Initiative.

Chambers, Scott A.; Yoo, Young K.

2003-10-10T23:59:59.000Z

404

Magnetic Storms  

Science Conference Proceedings (OSTI)

... magnetic reversal. As there is no predictive science of geomagnetism, we currently lack even simple forecasts. Our scientific ...

2010-10-05T23:59:59.000Z

405

Magnetic Properties  

Science Conference Proceedings (OSTI)

...Since the discovery of high-temperature superconductors in 1986 (Ref 10), the demonstration of magnetic flux exclusion

406

Chemical and Materials Science (XSD) | Advanced Photon Source  

NLE Websites -- All DOE Office Websites (Extended Search)

Chemical and Materials Science (X-ray Science Division) Chemical and Materials Science (X-ray Science Division) The CMS group has operational responsibility for four experiment stations at sector 12 including: three undulator stations (12-ID-B, -C, and -D), and a spectroscopy and scattering bending magnet beamline (12-BM), and USAXS at 15-ID. As part of the APS Strategic Plan, canted undulators have been installed on 12-ID and 12-ID-B has become a full-time dedicated SAXS beamline and 12-ID-C and 12-ID-D are shared between TRSAXS, ASAXS, and surface scattering. Time-resolved and anomalous SAXS experiments on photosystems, biopolymers, polymers, ceramics, and catalytic systems are some of the focus areas for 12-ID-B and -C. At 12-ID-D surface scattering are used to study MOCVD growth, ferroelectrics, liquid solid interfaces and

407

Doubly Salient Permanent Magnet Motor Development Review  

Science Conference Proceedings (OSTI)

The research of doubly salient permanent magnet motor (DSPM), arises as the emergence of a novel type mechatronic control of AC drive system. Currently, on the international realm, the studies regarding on this kind of motor mainly focus on calculation ... Keywords: Doubly Salient, Permanent Magnet Motor, AC Variable Speed, Magnetic Materials, Switched Reluctance Motor

Lina Yi, Meng Zhao

2013-09-01T23:59:59.000Z

408

Reactor Materials  

Energy.gov (U.S. Department of Energy (DOE))

The reactor materials crosscut effort will enable the development of innovative and revolutionary materials and provide broad-based, modern materials science that will benefit all four DOE-NE...

409

High Field Magnetic Resonance Facility  

NLE Websites -- All DOE Office Websites (Extended Search)

HFMRF Overview HFMRF Overview Section 2-3-1 High Field Magnetic Resonance Facility The High Field Magnetic Resonance Facility (HFMRF) focuses a significant portion of its research on developing a fundamental, molecular-level understanding of biochemical and biological systems and their response to environmental effects. A secondary focus is materials science, including catalysis and chemical mechanisms and processes. Staff and science consultants within this facility offer expertise in the areas of structural biology, solid-state materials characterization, and magnetic resonance imaging (MRI) techniques. Research activities in the HFMRF include: * structure determination of large molecular assemblies such as protein-DNA (normal and damaged DNA) and protein-RNA complexes

410

Thermodynamic measurements of applied magnetic materials  

E-Print Network (OSTI)

Thomas, and R.B. Zubeck. Heat capacity measurements on smallJ.A. Morrison. On the heat capacity of crystalline magnesiumDawson and D.H. Ryan. Heat capacity of silver paint. Review

Cooke, David William

2010-01-01T23:59:59.000Z

411

Metallurgy - Better magnetic materials | ornl.gov  

NLE Websites -- All DOE Office Websites (Extended Search)

are exploring ways to improve the quality of metals used in items such as cars, pipelines and nuclear reactors. This research could also help engineers create new metals and...

412

Magnetic Materials for Energy Applications II  

Science Conference Proceedings (OSTI)

Innovation in certain green energy technologies can lead to imbalances in rare earth element supply and demand, rare earths are critical to the performance of...

413

Electronic, Magnetic, and Photonic Materials: Selected Proceedings ...  

Science Conference Proceedings (OSTI)

Oct 15, 2006 ... ]Aluminum Oxynitride Dielectrics for High Energy Density Capacitor ... of 200 nm- Sized BaTiO3 Dielectric for Ultra High Capacitance MLCC...

414

Late Addition - Electronic and Magnetic Materials  

Science Conference Proceedings (OSTI)

144- The Role of Mn Content on Microstructure and Phases of High Alloyed White Cast Irons 145- The Synergy of XRD and XRF in a Shale and Slate Analysis.

415

Thermodynamic measurements of applied magnetic materials  

E-Print Network (OSTI)

6 Thermodynamic measurements of 6.1based scanning calorimeter for thermodynamic prop- erties ofK.J. Michel, and F. Hellman. Thermodynamic measurements of

Cooke, David William

2010-01-01T23:59:59.000Z

416

Thermodynamic measurements of applied magnetic materials  

E-Print Network (OSTI)

gold wires form a weak thermal link between this bolometermembrane provides a weak thermal link to the Si frame, whichboth as support and a weak thermal link to the sample stage.

Cooke, David William

2010-01-01T23:59:59.000Z

417

Magnetic Tunnel Junction Materials for Electronic Applications  

Science Conference Proceedings (OSTI)

In addition, the memory is nonvolatile (the information remains stored when the ... of the MRAM cell is essential for its competitiveness in the general memory market. ... and spin-down bands with different density of states at the Fermi energy. .... 15 . Further analysis shows that these hysteresis curves are consistent with the...

418

Characterizing Nanostructured Magnetic Materials with Photonic ...  

Science Conference Proceedings (OSTI)

... synchrotron light source facilities have been constructed and instrumentation .... data acquisition computer, which also controls the etalon scanning stage.

419

Session C: Electronic and Magnetic Materials  

Science Conference Proceedings (OSTI)

The effect of BiInO3 on phase transitions and thermal and electrical properties was .... Semi-insulating Fe-doped InP single crystals are grown in this work using the ... the powders were compacted in a cold uniaxial, cylindrical specimens were ...

420

Materials - Assessment  

NLE Websites -- All DOE Office Websites (Extended Search)

Materials Assessment The staff of the Energy Systems Division has a long history of technical and economic analysis of the production and recycling of materials for transportation...

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

Materials Science  

NLE Websites -- All DOE Office Websites (Extended Search)

Materials Science science-innovationassetsimagesicon-science.jpg Materials Science National security depends on science and technology. The United States relies on Los Alamos...

422

Composite, nanostructured, super-hydrophobic material  

DOE Patents (OSTI)

A hydrophobic disordered composite material having a protrusive surface feature includes a recessive phase and a protrusive phase, the recessive phase having a higher susceptibility to a preselected etchant than the protrusive phase, the composite material having an etched surface wherein the protrusive phase protrudes from the surface to form a protrusive surface feature, the protrusive feature being hydrophobic.

D' Urso, Brian R. (Clinton, TN); Simpson, John T. (Clinton, TN)

2007-08-21T23:59:59.000Z

423

Electrode Structures and Surfaces for Lithium Batteries | Argonne...  

NLE Websites -- All DOE Office Websites (Extended Search)

Electrode Structures and Surfaces for Lithium Batteries Technology available for licensing: lithium-metal-oxide electrode materials with modified surfaces to protect the materials...

424

Application of Nd-Fe-B Magnets to the Megawatt Scale Generator for ...  

Science Conference Proceedings (OSTI)

Various technologies for wind power generators such as interior permanent magnet (IPM) motors and surface permanent magnet (SPM) motors have been...

425

Definition: Ground Magnetics | Open Energy Information  

Open Energy Info (EERE)

Magnetics Magnetics Jump to: navigation, search Dictionary.png Ground Magnetics The surface magnetic method is the study of the distribution of magnetic minerals in the upper 20-30km of the earth's crust, recorded at an observation point on the earth's surface.[1][2] View on Wikipedia Wikipedia Definition A magnetometer, (pronounced mag-ne-TOM-e-ter), is a measuring instrument used to measure the strength and/or direction of the magnetic field, produced either in the laboratory or existing in nature. Some countries such as the USA, Canada and Australia classify the more sensitive magnetometers as military technology, and control their distribution. The International System of Units unit of measure for the strength of a magnetic field is the Tesla. This is a very large unit of magnetic field.

426

Magnetic reconnection launcher  

DOE Patents (OSTI)

An electromagnetic launcher includes a plurality of electrical stages which are energized sequentially in synchrony with the passage of a projectile. 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 by magnetic reconnection as the gap portion 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 at both the rear vertical surface of 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 and fit loosely within the gap between the opposing coils.

Cowan, Maynard (Albuquerque, NM)

1989-01-01T23:59:59.000Z

427

Linear Collider Final Focus Magnet Construction | Superconducting Magnet  

NLE Websites -- All DOE Office Websites (Extended Search)

Linear Collider Final Focus Magnet Construction Linear Collider Final Focus Magnet Construction The final focus magnets for the International Linear Collider require very small quadrupoles be placed within the detector background field for both the entrance and exit beams. The use of superconducting magnets for this function provide solutions to several problems confronting the machine designers. One constraint is the operation within the 3 tesla detector field. The direct wind magnets are capable of operation without the use of magnetic materials in their construction, making them ideal for compact focussing solutions within detectors. The second constraint is the small physical size dictated by the crossing angle of the beams and proximity to the IR within the detector solenoid. The Direct Wind design does not require a collar to withstand Lorentz

428

Disorder-Induced Microscopic Magnetic Memory  

NLE Websites -- All DOE Office Websites (Extended Search)

Disorder-Induced Microscopic Magnetic Memory Print Disorder-Induced Microscopic Magnetic Memory Print The magnetic-recording industry deliberately introduces carefully controlled disorder into its materials to obtain the desired magnetic properties. But as the density of magnetic disks climbs, the size of the magnetic domains responsible for storage must decrease, posing new challenges. Beautiful theories based on random microscopic disorder have been developed over the past ten years. To directly compare these theories with precise experiments, an American-European team, led by researchers from the University of Washington, Seattle, first developed and then applied coherent x-ray speckle metrology to microscopic magnetic domains in a series of thin multilayer perpendicular magnetic materials of varying disorder. Their results, at odds with all previous theories, have set a new reference point for future theories.

429

Disorder-Induced Microscopic Magnetic Memory  

NLE Websites -- All DOE Office Websites (Extended Search)

Disorder-Induced Microscopic Magnetic Memory Print Disorder-Induced Microscopic Magnetic Memory Print The magnetic-recording industry deliberately introduces carefully controlled disorder into its materials to obtain the desired magnetic properties. But as the density of magnetic disks climbs, the size of the magnetic domains responsible for storage must decrease, posing new challenges. Beautiful theories based on random microscopic disorder have been developed over the past ten years. To directly compare these theories with precise experiments, an American-European team, led by researchers from the University of Washington, Seattle, first developed and then applied coherent x-ray speckle metrology to microscopic magnetic domains in a series of thin multilayer perpendicular magnetic materials of varying disorder. Their results, at odds with all previous theories, have set a new reference point for future theories.

430

Disorder-Induced Microscopic Magnetic Memory  

NLE Websites -- All DOE Office Websites (Extended Search)

Disorder-Induced Microscopic Disorder-Induced Microscopic Magnetic Memory Disorder-Induced Microscopic Magnetic Memory Print Wednesday, 26 October 2005 00:00 The magnetic-recording industry deliberately introduces carefully controlled disorder into its materials to obtain the desired magnetic properties. But as the density of magnetic disks climbs, the size of the magnetic domains responsible for storage must decrease, posing new challenges. Beautiful theories based on random microscopic disorder have been developed over the past ten years. To directly compare these theories with precise experiments, an American-European team, led by researchers from the University of Washington, Seattle, first developed and then applied coherent x-ray speckle metrology to microscopic magnetic domains in a series of thin multilayer perpendicular magnetic materials of varying disorder. Their results, at odds with all previous theories, have set a new reference point for future theories.

431

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

432

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

433

X-Ray Imaging of the Dynamic Magnetic Vortex Core Deformation  

NLE Websites -- All DOE Office Websites (Extended Search)

new materials with new switching mechanisms. Uncovered by basic research into the fundamentals of magnetism, one such candidate consists of miniscule magnetic vortices like...

434

Design of a Ferrite Permanent Magnet Rotor for a Wind Power Generator.  

E-Print Network (OSTI)

?? Due to the insecurity of the supply of raw materials needed for neodymium-iron-boron magnets, typically used in permanent magnet generators, the use of ferrite (more)

Eklund, Petter

2013-01-01T23:59:59.000Z

435

Fe-rich FeSiBPCu Nano-crystalline Soft Magnetic Alloys ...  

Science Conference Proceedings (OSTI)

Symposium, Magnetic Materials for Energy Applications IV ... Fe-rich FeSiBPCu Nano-crystalline Soft Magnetic Alloys Contributable To Energy-saving. Author(s) ...

436

Recent Developments in Rare Earth Lean/Free High Energy Magnets  

Science Conference Proceedings (OSTI)

Fe-rich FeSiBPCu Nano-crystalline Soft Magnetic Alloys Contributable To Energy -saving Fe and Mn Based Materials for Magnetic Refrigeration First-order...

437

Thermoelectric Materials  

Science Conference Proceedings (OSTI)

Thermoelectric materials can generate electricity or provide cooling by converting thermal gradients to electricity or electricity to thermal gradients. More efficient thermoelectric materials would make feasible the widespread use of thermoelectric converters in mundane applications. This report summarizes the state-of-the-art of thermoelectric materials including currently available materials and applications, new developments, and future prospects.

2000-01-14T23:59:59.000Z

438

Velocity damper for electromagnetically levitated materials  

DOE Patents (OSTI)

A system for damping oscillatory and spinning motions induced in an electromagnetically levitated material. 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.

Fox, R.J.

1992-12-31T23:59:59.000Z

439

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

440

Material Disposal Areas  

NLE Websites -- All DOE Office Websites (Extended Search)

Material Disposal Areas Material Disposal Areas Material Disposal Areas Material Disposal Areas, also known as MDAs, are sites where material was disposed of below the ground surface in excavated pits, trenches, or shafts. Contact Environmental Communication & Public Involvement P.O. Box 1663 MS M996 Los Alamos, NM 87545 (505) 667-0216 Email Material Disposal Areas at LANL The following are descriptions and status updates of each MDA at LANL. To view a current fact sheet on the MDAs, click on LA-UR-13-25837 (pdf). MDA A MDA A is a Hazard Category 2 nuclear facility comprised of a 1.25-acre, fenced, and radiologically controlled area situated on the eastern end of Delta Prime Mesa. Delta Prime Mesa is bounded by Delta Prime Canyon to the north and Los Alamos Canyon to the south.

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

NUCLEAR FUEL MATERIAL  

DOE Patents (OSTI)

An improved method is given for making the carbides of nuclear fuel material. The metal of the fuel material, which may be a fissile and/or fertile material, is transformed into a silicide, after which the silicide is comminuted to the desired particle size. This silicide is then carburized at an elevated temperature, either above or below the melting point of the silicide, to produce an intimate mixture of the carbide of the fuel material and the carbide of silicon. This mixture of the fuel material carbide and the silicon carbide is relatively stable in the presence of moisture and does not exhibit the highly reactive surface condition which is observed with fuel material carbides made by most other known methods. (AEC)

Goeddel, W.V.

1962-06-26T23:59:59.000Z

442

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); Walls, Claudia A. (Oak Ridge, TN); Boatner, Lynn A. (Oak Ridge, TN)

2010-02-23T23:59:59.000Z

443

Feasibility of detecting artificial magnetic anomalies in hydrofractured rock by superconducting gradiometer-SQUID systems  

DOE Green Energy (OSTI)

A study of the signal physics of magnetic anomaly detection by superconducting gradiometer-SQUID systems to determine the feasibility of possible applications to the geothermal energy program is described. The system would make full use of the incredible sensitivity of the superconducting quantum interference device (SQUID) which can be in the range of 10/sup -11/ Oe. In addition to magnetic anomalies in the earth's field produced by spherical distributions of magnetic matter, anomalies that would be artificially produced by flooding magnetic material into cracks produced by hydrofracturing in deep boreholes drilled into dry rock geothermal sources are considered. The study indicates that surface detection by horizontal and vertical gradiometers of crack anomalies will not be feasible if the magnetic material flooding the crack is a paramagnetic solution. However, one can concoct a slurry to carry prepolarized ferromagnetic particles of a size sufficiently large to permit domain formation but small enough to permit rotation and alignment in the earth's field. In this case, the anomaly signal is large enough to permit extraction of anomaly orientation information out of the background of magnetic noise and earth's field gradients. The superconducting gradiometer-SQUID system is shown to be exceptional in its capability of removing undesirable magnetic noise and gradients. The greatest promise was found in systems that would be comprised of a magnetometer or gradiometer that could be lowered into the borehole to positions opposite the formations cracked by hydrofracturing. The use of a paramagnetic material to produce the artificial anomaly will not provide signals of sufficient amplitude to overcome the magnetic noise. However, the slurry containing only one percent by volume of ferromagnetic particles will produce a crack anomaly that is easily detectable by magnetometer or by the superconducting gradiometer-SQUID system.

Overton, W.C. Jr.

1976-12-01T23:59:59.000Z

444

Magnetohydrodynamic evolution of magnetic skeletons  

E-Print Network (OSTI)

The heating of the solar corona is likely to be due to reconnection of the highly complex magnetic field that threads throughout its volume. We have run a numerical experiment of an elementary interaction between the magnetic field of two photospheric sources in an overlying field that represents a fundamental building block of the coronal heating process. The key to explaining where, how and how much energy is released during such an interaction is to calculate the resulting evolution of the magnetic skeleton. A skeleton is essentially the web of magnetic flux surfaces (called separatrix surfaces) that separate the coronal volume into topologically distinct parts. For the first time the skeleton of the magnetic field in a 3D numerical MHD experiment is calculated and carefully analysed, as are the ways in which it bifurcates into different topologies. A change in topology normally changes the number of magnetic reconnection sites. In our experiment, the magnetic field evolves through a total of six distinct topologies. Initially, no magnetic flux joins the two sources. Then a new type of bifurcation, called a global double-separator bifurcation, takes place: this bifurcation is likely to be one of the main ways in which new separators are created in the corona (separators are field lines at which 3D reconnection takes place). This is the first of five bifurcations in which the skeleton becomes progressively more complex before simplifying. Surprisingly, for such a simple initial state, at the peak of complexity there are five separators and eight flux domains present.

Andrew L. Haynes; Clare E. Parnell; Klaus Galsgaard; Eric R. Priest

2007-02-22T23:59:59.000Z

445

Surface Protection for Enhanced Materials Performance  

Science Conference Proceedings (OSTI)

Oxidation and Erosion Behavior of Advanced Multi-Component Nano-Composite Turbine Compressor Blade Coatings Pack Aluminizing of Nickel: Modeling,...

446

Geotoxic materials in the surface environment  

Science Conference Proceedings (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

447

Surface Protection for Enhanced Materials Performance: Science ...  

Science Conference Proceedings (OSTI)

... Modeling Approach to Develop Protective Coatings for Fossil Energy Applications ... Doped Solid Oxide Fuel Cell Electrolytes Produced Via a Combination of...

448

Surface Protection for Enhanced Materials Performance: Science ...  

Science Conference Proceedings (OSTI)

Thermal Barrier Coatings for Resistance Against Attack by Molten Silicate Deposits from CMAS Sand, Volcanic Ash, or Coal Fly Ash Ingested by Gas- Turbine...

449

Functional Surfaces and Interfaces and New Materials  

Science Conference Proceedings (OSTI)

Functional Composites: Fluorescent Carbon Nanotubes in Silica Aerogel ... Novel Metallo-Organic Derived Ti-Si-Cr-C-N Nanocomposite Coatings: Part II...

450

Materials Science  

Science Conference Proceedings (OSTI)

Materials Science. Summary: Key metrologies/systems: In situ spectroscopic ellipsometry, linear and non-linear spectroscopies ...

2012-10-02T23:59:59.000Z

451

Training Materials  

Science Conference Proceedings (OSTI)

Training Materials. NIST Handbook 44 Self-Study Course. ... Chapter 3 Organization and Format of NIST Handbook 44 DOC. ...

2011-08-10T23:59:59.000Z

452

Material matting  

Science Conference Proceedings (OSTI)

Despite the widespread use of measured real-world materials, intuitive tools for editing measured reflectance datasets are still lacking. We present a solution inspired by natural image matting and texture synthesis to the material matting problem, ... Keywords: appearance models, material separation, matting, spatially-varying BRDFs, texture synthesis

Daniel Lepage; Jason Lawrence

2011-12-01T23:59:59.000Z

453

Materializing energy  

Science Conference Proceedings (OSTI)

Motivated and informed by perspectives on sustainability and design, this paper draws on a diverse body of scholarly works related to energy and materiality to articulate a perspective on energy-as-materiality and propose a design approach of ... Keywords: design, design theory, energy, materiality, sustainability

James Pierce; Eric Paulos

2010-08-01T23:59:59.000Z

454

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

455

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

456

Neural Network Mapping of Magnet Based Position Sensing System for Autonomous Robotic Vehicle  

Science Conference Proceedings (OSTI)

In this paper a neural network mapping of magnet based position sensing system for an autonomous robotic vehicle. The position sensing system using magnetic markers embedded under the surface of roadway pavement. An important role of magnetic position ...

Dae---Yeong Im; Young-Jae Ryoo; Jang-Hyun Park; Hyong-Yeol Yang; Ju-Sang Lee

2007-04-01T23:59:59.000Z

457

Superconducting Magnets  

NLE Websites -- All DOE Office Websites (Extended Search)

Mit Hilfe der Technologie supraleitender Magnete lassen sich in Mit Hilfe der Technologie supraleitender Magnete lassen sich in Ringbeschleunigern höhere Energien erreichen. Weil supraleitende Spulen keinen elektrischen Widerstand aufweisen, können damit stärkere Magnetfelder erzeugt werden. In normal leitenden Elektromagneten wird - wegen des elektrischen Widerstands der Drähte - die Spule aufgeheizt. Auf diese Weise geht sehr viel Energie in Form von Wärme verloren, was die Energiekosten dieser Magnete in die Höhe treibt. Supraleitende Spulen erlauben es, Magnete grosser Feldstärke unter günstigen Bedingungen zu betreiben und damit die Energiekosten zu senken. Durch den Einbau supraleitender Spulen in den Ringbeschleuniger von Fermilab konnte dessen Energie verdoppelt werden.Auch der im Bau befindliche "Large Hadron Collider" am CERN wird supraleitende Magnete

458

Integrating giant microwave absorption with magnetic refrigeration in one  

E-Print Network (OSTI)

Integrating giant microwave absorption with magnetic refrigeration in one multifunctional with magnetic refrigeration in one multifunctional material. This integration not only advances our EMI problem, it is becoming very urgent to design and fabricate the electromagnetic compatibility (EMC

Wang, Wei Hua

459

Apparatus and method for pyrolyzing biomass material  

DOE Patents (OSTI)

A technique for pyrolyzing biomass materials is disclosed wherein a hot surface is provided having a predetermined temperature which is sufficient to pyrolyze only the surface strata of the biomass material without substantially heating the interior of the biomass material thereby providing a large temperature gradient from the surface strata inwardly of the relatively cool biomass materials. Relative motion and physical contact is produced between the surface strata and the hot surface for a sufficient period of time for ablative pyrolyzation by heat conduction to occur with minimum generation of char.

Diebold, J.P.; Reed, T.B.

1981-08-21T23:59:59.000Z

460

Materials Education Community  

Science Conference Proceedings (OSTI)

Digital Resource Center Home. Materials Education. Materials Education. Established Materials Technologies. Magnesium Superalloys. Emerging Materials...

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.


461

Emerging Materials Technologies  

Science Conference Proceedings (OSTI)

Digital Resource Center Home. Materials Education. Materials Education. Established Materials Technologies. Magnesium Superalloys. Emerging Materials...

462

Established Materials Technologies  

Science Conference Proceedings (OSTI)

Digital Resource Center Home. Materials Education. Materials Education. Established Materials Technologies. Magnesium Superalloys. Emerging Materials...

463

Magnetic nanoparticles for applications in oscillating magnetic field  

DOE Green Energy (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

464

Workshop on innovation in materials processing and manufacture: Exploratory concepts for energy applications  

DOE Green Energy (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

465

G22: A Novel Biomedical ?-type Ti alloy TLM materials Used in ...  

Science Conference Proceedings (OSTI)

Metamagnetic Martensitic Transformation and Ductility of Ni-Cu-Mn-Ga Magnetic ... Research on Bioinspired Functional Materials Derived from Natural Materials.

466

Magnetics Portal  

Science Conference Proceedings (OSTI)

... Step Toward 'Atomtronics'. New Filtration Material Could Make Petroleum Refining Cheaper, More Efficient. New NIST Microscope ...

2013-06-13T23:59:59.000Z

467

Materials Applications of Photoelectron Emission Microscopy  

SciTech Connect

Photoelectron emission microscopy (PEEM) is a versatile technique that can image a variety of materials including metals, semiconductors and even insulators. Under favorable conditions the most advanced aberration corrected instruments have a spatial resolution approaching 2 nm. Although PEEM cannot compete with transmission or scanning electron microscopies for ultimate resolution, the technique is much more gentle and has the unique advantage of imaging structure as well as electronic and magnetic states on the nanoscale. Since the image contrast is derived from spatial variations in electron photoemission intensity, PEEM is ideal for interrogating both static and dynamic electronic properties of complex nanostructured materials. PEEM can be performed using a variety of photoexcitation sources including synchrotron emission, femtosecond laser pulses and conventional UV lamp emission. Each source has advantages, for example, fs laser excitation enables time-resolved imaging for study of ultrafast dynamics of surface intermediate states while tunable synchrotron sources allow chemically specific excitation. Even more detail can be extracted from energy resolved PEEM. Here, we review the key principles and contrast mechanisms of PEEM and briefly summarize materials applications of PEEM with examples of a thermally-induced structural phase transformation in barium titanate, inter-diffusion between thin metal copper and ruthenium layers, and multiphoton imaging of polystyrene nanoparticles on a silver coated substrate.

Xiong, Gang; Shao, Rui; Peppernick, Samuel J.; Joly, Alan G.; Beck, Kenneth M.; Hess, Wayne P.; Cai, Mingdong; Duchene, J.; Wang, J. Y.; Wei, Wei

2010-12-30T23:59:59.000Z

468

How the Performance of a Superconducting Magnet is affected by the Connection between a small cooler and the Magnet  

E-Print Network (OSTI)

to the magnet) and a condenser that is connected to thetemperature drop between the condenser and the cold head (Tdrop between the condenser and the magnet surface (T 2 -T

Green, Michael A.

2005-01-01T23:59:59.000Z

469

Ramesh Gupta | Superconducting Magnet Division  

NLE Websites -- All DOE Office Websites (Extended Search)

Ramesh Gupta Ramesh Gupta Ramesh Gupta has always been a leader in the world of superconducting magnets, which are essential to great modern accelerators such as the Relativistic Heavy Ion Collider at BNL, and the Large Hadron Collider at CERN, Switzerland. For the past decade, Lab researchers have been exploring the use of new materials that become superconducting at higher temperatures. Gupta, head of the High Temperature Superconductor (HTS) Research and Development Group in the Superconducting Magnet Division, is among those exploring avenues for HTS magnets that are energy efficient and have magnetic fields that are a million times stronger than the Earth's. These new magnets could revolutionize use in future accelerators, play a key role in energy efficiency and storage, and make possible new

470

Many-body Interactions in Magnetic Films and Nanostructures  

SciTech Connect

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

471

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); Mar