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1

Neutron Powder Diffraction Workshop (NPD2011)  

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

Workshop Contact Information Instructors Application Form Sample Description HB2A at HFIR POWGEN at SNS filler About the Workshop Neutron powder diffraction is a widely used...

2

Magnetic Structure Analysis from Neutron Powder Diffraction Data Using GSAS  

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

Magnetic Structure Analysis from Neutron Powder Diffraction Data Using GSAS Magnetic Structure Analysis from Neutron Powder Diffraction Data Using GSAS This set of web pages provides reference information from the Magnetic Structure Analysis from Neutron Powder Diffraction Data Using GSAS workshop presented at the 2006 American Conference on Neutron Scattering held in St. Charles, IL, June 18-22, 2006. Workshop Schedule: 9:00-9:05 am: Introduction (B.H. Toby) 9:05-9:50 am: History, Color symmetry & Shubnikov space groups (B. Chakoumous) Lecture notes: History and Color symmetry & Shubnikov space groups 9:50-10:20 am: Magnetic extinctions classes & common magnetic structure types (R.B. Von Dreele) Lecture Notes Break 10:50-11:45 am: Overview of representational analysis & FullProf implementation (L.C. Chapon) Lecture Notes and Accompanying files

3

Powder Diffraction  

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

Powder Diffraction Powder Diffraction Ashfia Huq Spallation Neutron Source Oak Ridge National Laboratory 2 Managed by UT-Battelle for the U.S. Department of Energy Bragg's law W.H. Bragg (1862-1942) W.L. Bragg (1890-1971) *Zinc Blend (fcc not sc) *NaCl (not molecular) *Diamond (two overlapping fcc lattice) Shared 1915 Nobel Prize 3 Managed by UT-Battelle for the U.S. Department of Energy Where are the atoms? X-ray: (l : 10 -9 m - 10 -11 m) l[Å] = 12.398/E ph [keV] Source: * Lab diffractometers * Synchrotron Sources Neutron: (thermal l : 1-4Å) E n [meV] =81.89/ l 2 [Å] Source: * Reactors (fission) * Spallation Source We need wavelength (l) ~ Object size (for condensed matter that is Å) 4 Managed by UT-Battelle for the U.S. Department of Energy

4

Powder diffraction in materials science using the KENS cold-neutron source  

SciTech Connect

Since superconductivity fever spread around the world, neutron powder diffraction has become very popular and been widely used by crystallographers, physicists, chemists, mineralogists, and materials scientists. The purpose of present paper is to show, firstly, important characteristics of time-of-flight TOF powder diffraction using cold-neutron source in the study of materials science, and, secondly, recent studies on the structure and function of batteries at the Neutron Science Laboratory (KENS) in the High Energy Accelerator Research Organization (KEK).

Kamiyama, T.; Oikawa, K. [Univ. of Tsukuba (Japan). Inst. of Materials Science; Akiba, E. [National Inst. of Materials and Chemical Research, Tsukuba (Japan)] [and others

1997-12-01T23:59:59.000Z

5

In Situ Neutron Powder Diffraction on Hydrogen Storage Materials  

Science Conference Proceedings (OSTI)

Abstract Scope, In order to pursue hydrogen storage research on powder samples ... A Case Study in Future Energy Challenges: Towards In Situ Hard X-

6

Measurement of the electrostrictive coefficients of modified lead magnesium niobate using neutron powder diffraction  

Science Conference Proceedings (OSTI)

Neutron powder diffraction measurements and a constitutive model were used to determine the bulk longitudinal and transverse electrostrictive coefficients (Q{sub ijkl}) for polycrystalline samples of the subject material. Effective single-crystal Q{sub ijkl} were calculated from the powder neutron diffraction data. The resulting values of the three independent Q{sub ijkl}, as determined from the cubic symmetry of the underlying lattice, are Q{sub 3333}=2.1{times}10{sup {minus}2}m{sup 4}/C{sup 2}, Q{sub 3322}={minus}0.87{times}10{sup {minus}2}m{sup 4}/C{sup 2}, and Q{sub 3232}=1.2{times}10{sup {minus}2}m{sup 4}/C{sup 2}. Using these effective single-crystal values, a random ensemble average was used to predict the electromechanical performance of the polycrystalline material. Predicted values of bulk Q{sub 3333}=1.86{times}10{sup {minus}2}m{sup 4}/C{sup 2} and Q{sub 3322}={minus}0.78{times}10{sup {minus}2}m{sup 4}/C{sup 2} are 89{percent} and 87{percent}, respectively, of the effective single-crystal values for Q{sub 3333} and Q{sub 3322}, while measured values of polycrystalline specimens are only {approximately}70{percent} of the single-crystal values. {copyright} {ital 1998 American Institute of Physics.}

Misture, S.T.; Pilgrim, S.M. [New York State College of Ceramics at Alfred University, Alfred, New York 14802 (United States); Hicks, J.C.; Blue, C.T. [Materials, Sensors, and Systems Branch, Code D364, NCCOSC/RDTE Division, San Diego, California 92152-6147 (United States); Payzant, E.A.; Hubbard, C.R. [Oak Ridge National Laboratory, Oak Ridge, Tennessee 37831 (United States)

1998-03-01T23:59:59.000Z

7

UNITED STATES ATOMIC ENERGY COMMISSION OAK RIDGE TENNESSEE THE DIFFRACTION OF NEUTRONS BY CRYSTALLINE POWDERS  

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

MDDC 869 MDDC 869 UNITED STATES ATOMIC ENERGY COMMISSION OAK RIDGE TENNESSEE THE DIFFRACTION OF NEUTRONS BY CRYSTALLINE POWDERS by E. 0. Wollan C. G. Shull Clinton Laboratories Published for use within the Atomic Energy Commission. Inquiries for additional -copies and any questions regarding reproduction by recipients of this document may be referred to the Documents Distribution Subsection, Publication Section, Technical Information Branch, Atomic Energy Commission, P. 0. Box E, Oak Ridge, Tennessee. Inasmuch as a declassified document may differ materially from the original classified document by reason of deletions necessary to accomplish declassification, this copy does not constitute authority for declassification of classified copies of a similar document which may bear the same title and authors.

8

Neutron Powder Diffraction of the Mg6Pd and Mg6Pd + Fe ...  

Science Conference Proceedings (OSTI)

To improve magnesium's hydrogen absorption properties, palladium was ball milled ... hydrogen in three disproportional reactions; Mg6Pd + 2.35H2 + energy ... In-situ Chemistry Mapping of Hydrogen Storage Materials by Neutron Diffraction.

9

POWDER: The Neutron Powder Diffractometer at HFIR | ORNL Neutron Sciences  

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

Neutron Powder Diffractometer Neutron Powder Diffractometer Neutron Powder Diffractometer. Neutron Powder Diffractometer. The HB-2A diffractometer is a workhorse instrument used to conduct crystal structural and magnetic structural studies of powdered and ceramic samples, particularly as a function of intensive conditions (T, P, H, etc.). Powder diffraction data collected on this instrument are ideally suited for the Rietveld method. A full range of ancillary sample environments can be used, including cryofurnaces (4-800 K), furnaces (to 1800 K), cryostats (to 0.3 K), and cryomagnets (to 7 T). The Powder Diffractometer has a Debye-Scherrer geometry. The detector bank has 44 3He tubes, each with 6' Soller collimators. A germanium wafer-stack monochromator is vertically focusing and provides one of three principal

10

Neutron Powder Diffraction and Molecular Simulation Study of the Structural Evolution of Ammonia Borane from 15 to 340 K  

Science Conference Proceedings (OSTI)

The structural behavior of perdeuterated, 11B-enriched ammonia borane, ND311BD3, was investigated by neutron powder diffraction measurements collected over the temperature range from 15 to 340 K and by molecular dynamics simulation. In the low temperature orthorhombic phase, the progressive displacement of the borane group under the amine group was observed leading to the rotation of the B-N bond parallel to the c-axis. The structural phase transition at 225 K is marked by dramatic change in the dynamics of both the amine and borane group that is problematic to extract from the metrics provided by Rietveld analysis of the NPD data alone but is evident in the molecular dynamics simulation and other spectroscopic evidence. This study highlights the valued added by complimentary experimental approaches and coupled computational studies.

Hess, Nancy J.; Schenter, Gregory K.; Hartman, Michael R.; Daemen, Luke L.; Proffen, Thomas E.; Kathmann, Shawn M.; Mundy, Christopher J.; Hartl, Monika A.; Heldebrant, David J.; Stowe, Ashley C.; Autrey, Thomas

2009-04-17T23:59:59.000Z

11

POWDER: The Neutron Powder Diffractometer at HFIR | ORNL Neutron...  

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

powder diffraction include (but are not limited to) catalysts, ionic conductors, superconductors, alloys, intermetallic compounds, ceramics, cements, colossal magnetoresistance...

12

Neutron Diffraction @ TOPAZ  

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

Topaz Guide Bender Topaz Guide Bender Neutron Diffraction @ TOPAZ Workshop on Single Crystal Neutron Diffraction picture 2 September 29 - October 1, 2011 * Spallation Neutron Source * Oak Ridge National Laboratory * Oak Ridge TN, USA TOPAZ 2011 Home Contacts Agenda and Important Deadlines Registration and Payment filler Workshop summary and purpose A workshop on single crystal neutron diffraction will be held at the Spallation Neutron Source at the Oak Ridge National Laboratory (ORNL). It will present invited and contributed talks to showcase cutting edge science and examples where neutron diffraction can make significant contributions; and provide training in neutron structure analysis and sample screening for the preparation of instrument beam-time proposals. TOPAZ is a high resolution wavelength-resolved Laue diffractometer with a versatile sample environment. Commissioning user experiments have demonstrated successfully the instrument capability for structural study of a vitamin B12 derivative, ion distribution in Li-ion battery materials, order and disorder in shape memory intermetallics, magnetic phase transition in multiferroic single crystal and functional thin films. The workshop is directed towards experienced neutron diffraction users and new users alike and encourages members to highlight their research and interest in structure analysis and investigation. The workshop will give opportunity to bring your own single crystal and screen sample quality and scattering power on TOPAZ @ room temperature, to evaluate data collection time and quality for an anticipated experiment. Finally, an opportunity to compose a proposal for neutron beam time (http://neutrons.ornl.gov/users/proposals.shtml) with staff will be provided in the framework of the workshop. The workshop format is well suited for researchers to contribute by showcasing their research and bring their research group or graduate student, who would like to test a single crystal sample. User access training for the ORNL neutron scattering facility will be included. It will be valid for future experiments.

13

SINGLE CRYSTAL NEUTRON DIFFRACTION.  

SciTech Connect

Single-crystal neutron diffraction measures the elastic Bragg reflection intensities from crystals of a material, the structure of which is the subject of investigation. A single crystal is placed in a beam of neutrons produced at a nuclear reactor or at a proton accelerator-based spallation source. Single-crystal diffraction measurements are commonly made at thermal neutron beam energies, which correspond to neutron wavelengths in the neighborhood of 1 Angstrom. For high-resolution studies requiring shorter wavelengths (ca. 0.3-0.8 Angstroms), a pulsed spallation source or a high-temperature moderator (a ''hot source'') at a reactor may be used. When complex structures with large unit-cell repeats are under investigation, as is the case in structural biology, a cryogenic-temperature moderator (a ''cold source'') may be employed to obtain longer neutron wavelengths (ca. 4-10 Angstroms). A single-crystal neutron diffraction analysis will determine the crystal structure of the material, typically including its unit cell and space group, the positions of the atomic nuclei and their mean-square displacements, and relevant site occupancies. Because the neutron possesses a magnetic moment, the magnetic structure of the material can be determined as well, from the magnetic contribution to the Bragg intensities. This latter aspect falls beyond the scope of the present unit; for information on magnetic scattering of neutrons see Unit 14.3. Instruments for single-crystal diffraction (single-crystal diffractometers or SCDs) are generally available at the major neutron scattering center facilities. Beam time on many of these instruments is available through a proposal mechanism. A listing of neutron SCD instruments and their corresponding facility contacts is included in an appendix accompanying this unit.

KOETZLE,T.F.

2001-03-13T23:59:59.000Z

14

Neutron detectors comprising boron powder  

DOE Patents (OSTI)

High-efficiency neutron detector substrate assemblies comprising a first conductive substrate, wherein a first side of the substrate is in direct contact with a first layer of a powder material comprising .sup.10boron, .sup.10boron carbide or combinations thereof, and wherein a conductive material is in proximity to the first layer of powder material; and processes of making said neutron detector substrate assemblies.

Wang, Zhehui; Morris, Christopher; Bacon, Jeffrey Darnell; Makela, Mark F; Spaulding, Randy Jay

2013-05-21T23:59:59.000Z

15

Magnetic Structure Determination from Neutron Diffraction Data  

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

logo logo Magnetic Structure Determination from Neutron Diffraction Data September 17 - 20, 2012 logo Oak Ridge National Laboratory - Oak Ridge, Tennessee, USA About the Workshop Program Lecture Notes Useful Links Organizers Travel & Lodging Wireless Networking Photos filler About the Workshop molecule The Magnetic Structure Determination Workshop 2012 concluded on September 20. The aim of this workshop was to enhance the community studying magnetism in materials by learning from experts the essential theoretical foundations to magnetic representation analysis and work through real examples to gain experience in solving and refining magnetic structures from neutron powder and single crystal diffraction data. Invited speakers: Juan Rodríguez-Carvajal (ILL, Grenoble)

16

Crystal structure of (Li{sub 0.5}K{sub 0.5}){sub 2}CO{sub 3} by neutron powder diffraction analysis  

DOE Green Energy (OSTI)

The crystal structure of (Li{sub 0.5}K{sub 0.5}){sub 2}CO{sub 3} was determined by neutron powder diffraction. A final weighted R-factor of 4.54% was obtained for the refinement of 2,373 reflections by the Rietveld method from a sample synthesized using {sup 7}Li{sub 2}CO{sub 3} and K{sub 2}CO{sub 3} (99.9% pure). Slight distortion of the CO{sub 3}{sup 2{minus}} units in the monoclinic cell was observed; the O(1)-C-O(2) angle and C-O(3) length are larger than those for the other C-O bonds and O-C-O angles. These local-structure characteristics can be explained by the difference in the ionic size of Li{sup +} and K{sup +}, and the different electrostatic interactions between the cations and CO{sub 3}{sup 2{minus}} units. (Li{sub 0.5}K{sub 0.5}){sub 2}CO{sub 3} is important as a material for molten carbonate fuel cells.

Idemoto, Yasushi [Argonne National Lab., IL (United States). Intense Pulsed Neutron Source]|[Science Univ. of Tokyo, Noda, Chiba (Japan). Dept. of Industrial Chemistry; Richardson, J.W. Jr.; Loong, C.K. [Argonne National Lab., IL (United States). Intense Pulsed Neutron Source; Koura, Nobuyuki; Kohara, Shinji [Science Univ. of Tokyo, Noda, Chiba (Japan). Dept. of Industrial Chemistry

1997-08-01T23:59:59.000Z

17

A neutron powder diffraction study of. cap alpha. - and. beta. -PbO/sub 2/ in the positive electrode material of lead-acid batteries  

SciTech Connect

A neutron powder diffraction study of ..cap alpha..- and ..beta..-PbO/sub 2/, both chemically prepared and electrochemically formed in cycled battery plates, was carried out to correlate the electrochemical activity of the lead-acid battery with the atomic arrangement of the electrode constituents. Our results are consistent with the presence of hydrogen in the structure of ..beta..-PbO/sub 2/, but the departure of the occupancy factors from stoichiometric values are not large enough to unambiguously establish whether there are lead or oxygen deficiencies. If the Pb:O ratio corresponds to exact stoichiometry, any hydrogen which is present must be accompanied by a reduction of Pb/sup +4/. There is a significant increase in the lattice parameter ..cap alpha.. of ..beta..-PbO/sub 2/ in cycled battery electrodes relative to the value found in chemically prepared ..beta..-PbO/sub 2/. No change in the c parameter, however, was detected. These dimensional changes are consistent with a configuration for hydrogen similar to that observed in the rutile type structure of SnO/sub 2/, in which there are OH-ions oriented perpendicular to the c axis. The profile parameters obtained in this analysis show that the crystallites of ..beta..-PbO/sub 2/ in the positive plate material of a battery cycled three times (Y3) are smaller than those in the chemically prepared compound (about 450A vs. 800A), while there are no significant differences between the latter and ..beta..-PbO/sub 2/ in the positive plate material of a battery cycled 36 times (Y36). The average structure of ..cap alpha..-PbO/sub 2/ cannot be accurately determined by profile analysis, at the present time. The difficulties encountered in the refinement may be due to extensive defects, nonspherical crystallites of small size, and/or small departures of the structure from orthorhombic symmetry.

Santoro, A.; Caulder, S.M.; D' Antonio, P.

1983-07-01T23:59:59.000Z

18

Palladium deuteride formation in the cathode of an electrochemical cell: An in situ neutron diffraction study  

DOE Green Energy (OSTI)

In this report, neutron diffraction of palladium cathodes is utilized to reveal palladium deuteride formation within the crystal structure of the metal. The experiment described in this report demonstrates the efficacy of neutron powder diffraction as a tool for structural studies of metal deuterides/hydrides and the feasibility of in situ diffraction measurements from a working electrochemical cell. (JL)

Rotella, F.J.; Richardson, J.W. Jr.; Redey, L.; Felcher, G.P.; Hitterman, R.L.; Kleb, R.

1991-12-31T23:59:59.000Z

19

Clifford G. Shull, Neutron Diffraction, Hydrogen Atoms, and Neutron  

Office of Scientific and Technical Information (OSTI)

Clifford Shull, Neutron Diffraction, and Neutron Scattering Clifford Shull, Neutron Diffraction, and Neutron Scattering Resources with Additional Information Clifford G. Shull was awarded the 1994 Nobel Prize in Physics "for the development of the neutron diffraction technique". 'Professor Shull's prize was awarded for his pioneering work in neutron scattering, a technique that reveals where atoms are within a material like ricocheting bullets reveal where obstacles are in the dark. Clifford Shull Photo Courtesy of Oak Ridge National Laboratory When a beam of neutrons is directed at a given material, the neutrons bounce off, or are scattered by, atoms in the sample being investigated. The neutrons' directions change, depending on the location of the atoms they hit, and a diffraction pattern of the atoms' positions can then be obtained.

20

Thermostat for neutron-diffraction apparatus  

SciTech Connect

This paper describes a thermostat which has been designed for neutron-diffraction studies. The thermostat does not introduce any distortions into the beam of neutrons diffracted from the specimen. The range of operating temperatures is 300-1300 degrees K and the vacuum is 10/sup -6/ torr. The thermostat permits liquid, solid, and amorphous specimens to be studied.

Kozlov, E.N.; Nikolaev, V.O.; Skovorod'ko, S.N.; Tsirkunova, S.E.

1985-09-01T23:59:59.000Z

Note: This page contains sample records for the topic "neutron powder diffraction" 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

Hydrogen in polar intermetallics: Syntheses and structures of the ternary Ca5Bi3D0.93, Yb5Bi3Hx, and Sm5Bi3H~1 by powder neutron or single crystal X-ray diffraction  

DOE Green Energy (OSTI)

The syntheses of the title compounds are described in detail. Structural characterizations from refinements of single crystal X-ray diffraction data for Yb{sub 5}Bi{sub 3}H{sub x} and Sm{sub 5}Bi{sub 3}H{sub 1} and of powder neutron diffraction data for Ca{sub 5}Bi{sub 3}D{sub 0.93(3)} are reported. These confirm that all three crystallize with the heavy atom structure type of {beta}-Yb{sub 5}Sb{sub 3}, and the third gives the first proof that the deuterium lies in the center of nominal calcium tetrahedra, isostructural with the Ca{sub 5}Sb{sub 3}F-type structure. These Ca and Yb phases are particularly stable with respect to dissociation to Mn{sub 5}Si{sub 3}-type product plus H{sub 2}. Some contradictions in the literature regarding Yb{sub 5}Sb{sub 3} and Yb{sub 5}Sb{sub 3}H{sub x} phases are considered in terms of adventitious hydrogen impurities that are generated during reactions in fused silica containers at elevated temperatures.

Leon-Escamilla, E. Alejandro; Dervenagas, Panagiotis; Stasis, Constantine; Corbett, John D.

2010-01-01T23:59:59.000Z

22

Neutron Diffraction in the Toolbox for Materials Science and ...  

Science Conference Proceedings (OSTI)

Neutron Diffraction Studies of Residual Stresses around Gouges and Gouged Dents in Pipelines Neutron Diffraction Study and EVPSC Modeling of the...

23

Photon Sciences | Beamlines | XPD: X-ray Powder Diffraction  

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

XPD: X-ray Powder Diffraction XPD: X-ray Powder Diffraction Poster | Fact Sheet | Preliminary Design Report Scientific Scope XPD is a tunable facility with the ability to collect diffraction data at high x-ray energies (40keV-80keV), offering rapid acquisition (millisecond) and high angular resolution capabilities on the same instrument. XPD addresses future scientific challenges in, for example, hydrogen storage, CO2 sequestration, advanced structural ceramics, catalysis, and materials processing. Such materials of high technological value often are complex, nanostructured and heterogeneous. The scientific grand challenge is to obtain robust and quantitative (micro)structural information, not only in the ground state at ambient conditions, but also in situ or in operando with varying temperature, pressure, magnetic/electric/stress

24

Ris-M-2874 Neutron Diffraction Experiments  

E-Print Network (OSTI)

;1. Introduction The nuclear spin systems in metals provide ideal models to test theoretical ideas by experiments Roskilde, Denmark August 1990 #12;Abstract Nuclear spins in silver constitute an ideal antiferromagnetic study the feasibility of neutron diffraction experiments on nuclear magnetic order in silver

25

Model independent pre-processing of X-ray powder diffraction profiles  

Science Conference Proceedings (OSTI)

Precise knowledge of X-ray diffraction profile shape is crucial in the investigation of the properties of matter in crystals powder. Line-broadening analysis is the fourth pre-processing step in most of the full powder pattern fitting softwares. The ... Keywords: Hankel--Lanczos singular value decomposition (HLSVD), Morphological filtering, X-ray powder diffraction

M. Ladisa; A. Lamura; T. Laudadio; G. Nico

2007-01-01T23:59:59.000Z

26

Neutron Diffraction Studies of Intercritically Austempered Ductile Irons  

Science Conference Proceedings (OSTI)

... a function of applied stress were determined using neutron diffraction at the NRSF2 at the High Flux Isotope Reactor (HFIR) at Oak Ridge National Laboratory.

27

Materials Science by High-energy Powder Diffraction: Opportunities ...  

Science Conference Proceedings (OSTI)

Symposium, O. Advanced Neutron and Synchrotron Studies of Materials .... Status of China Spallation Neutron Source and Perspectives of Neutron Research in...

28

LANSCE | Lujan Center | Highlights | In situ neutron diffraction study of  

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

In situ neutron diffraction study of CO clathrate hydrate In situ neutron diffraction study of CO clathrate hydrate The structure of a CO clathrate hydrate has been studied for the first time using high-P low-T neutron diffraction. Clathrate Rietveld analysis shows that lattice parameter a (SII cubic clathrate structure) increases with increasing temperature. CO molecules are positionally disordered and off-centered in both large and small cages. Each large cage is occupied by two CO molecules while each small cage is occupied by one CO. A representative neutron diffraction pattern of SII CO clathrate hydrate. Variation of lattice parameter a of CO SII clathrate hydrate as a function of temperature. A representative neutron diffraction pattern of SII CO clathrate hydrate. Variation of lattice parameter a of CO SII clathrate hydrate as a function of temperature.

29

Publications from Research Conducted at POWDER | ORNL Neutron...  

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

P., Cao H., Madiligama A. S.B., Koledov V., "Neutron diffraction study of a non-stoichiometric Ni-Mn-Ga MSM alloy", Materials Science Forum 738-739, 103-107 (2013). Chakoumakos...

30

POWDER DIFFRACTION BEAMLINE FOR IN SITU STUDIES OF STRUCTURAL...  

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

tunable x-ray energy from 5 to 25 keV. * Powder crystallography, including solving and refining crystal structures, quantitative analysis of phase fraction and sizestrain...

31

In-Situ Neutron-Diffraction Study of a Ferritic Superalloy during ...  

Science Conference Proceedings (OSTI)

The neutron diffraction experiments were conducted at VULCAN diffractometer, Spallation Neutron Source, ORNL, with the state-of-art thermomechanical...

32

Temperature and TimeResolved XRay Powder Diffraction X14A EERE sponsored PRT beamline  

E-Print Network (OSTI)

Temperature and TimeResolved XRay Powder Diffraction X14A EERE sponsored PRT beamline Objective, in ambience or with gas flow Capabilities: X14A, EERE-sponsored PRT beamline · High photon flux: typically 9x

Homes, Christopher C.

33

Identification of Compounds and Phases Using X-Ray Powder Diffraction  

Science Conference Proceedings (OSTI)

Table 1(a)   Identification of powder diffraction pattern from Al 2 O 3 using the Hanawalt search method...pattern from Al 2 O 3 using the Hanawalt search method The diffracting angles and intensities (area under each peak)

34

Structure and Dynamics of Cholesterol-Containing Polyunsaturated Lipid Membranes Studied by Neutron Diffraction and NMR  

E-Print Network (OSTI)

by Neutron Diffraction and NMR Mihaela Mihailescu Olivierwas carried out by neutron diffraction, 2 H-NMR and 13C-MAS NMR. Scattering length distribution func- tions of

Mihailescu, Mihaela; Soubias, Olivier; Worcester, David; White, Stephen H.; Gawrisch, Klaus

2011-01-01T23:59:59.000Z

35

ON THE COVER Neutron powder diffraction pattern of a chabazite  

E-Print Network (OSTI)

-Products Utilization Geopolymer Concrete (GPC) · Proposed by Devidovits (1994) is an upcoming technology-friendly and sustainable. #12;Center for By-Products Utilization Geopolymer Concrete (cont'd) · Industrial byCenter for By-Products Utilization Sustainable Concrete with Industrial and Post-Consumer By

Perkins, Richard A.

36

POWGEN - The Powder Diffractometer at SNS - ORNL Neutron Sciences  

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

Powder Diffractometer at SNS POWGEN news: Research makes the cover of Inorganic Chemistry POWGEN detector array POWGEN detector array. POWGEN is a general-purpose powder...

37

In-Situ Neutron Diffraction Study of Porous NiO-YSZ Composite ...  

Science Conference Proceedings (OSTI)

Presentation Title, In-Situ Neutron Diffraction Study of Porous NiO-YSZ Composite ... Gas Turbines of the Future: Hydrogen and Oxy-Combustion Environments.

38

Neutron Diffraction Studies of the Tri-axial Stress Distribution in ...  

Science Conference Proceedings (OSTI)

Here neutron diffraction strain scanning, originally developed for residual stress measurements, is applied to the stress distribution in granular materials under a...

39

In-situ neutron diffraction and crystal plasticity modeling of ?-Uranium  

Science Conference Proceedings (OSTI)

The present study uses a combination of in-situ neutron diffraction and crystal plasticity modeling to elucidate the deformation mechanisms active in ?-Uranium.

40

Neutron diffraction measurements of residual stresses in welds fabricated from highly anisotropic materials  

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

neutron diffraction to neutron diffraction to engineering problems T.M. Holden Northern Stress Technologies Deep River, Ontario, Canada Oak Ridge National Laboratory, 13 nd June 2011 Reference material * "Introduction to the characterization of residual stress by neutron diffraction". M.T. Hutchings, P.J. Withers, T.M. Holden and T. Lorentzen, (Taylor and Francis: Boca Raton) 2005 * "Introduction to diffraction in Materials Science and Engineering", A.D. Krawitz (John Wiley and Sons ,Inc.: New York) 2001 * "Non-destructive testing-Standard Test Method for

Note: This page contains sample records for the topic "neutron powder diffraction" 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

Neutron-Diffraction Evidence for the Ferrimagnetic Ground State of a Molecule-Based Magnet with Weakly Coupled Sublattices  

SciTech Connect

The diruthenium compound [Ru2(O2CMe)4]3[Cr(CN)6] contains two weakly coupled, ferrimag- netically ordered sublattices occupying the same volume. The magnetic field Hc 800 Oe required to align the two sublattice moments is proportional to the antiferromagnetic dipolar interaction Kc B Hc 5 10 3 meV between sublattices. Powder neutron-diffraction measurements on a deuterated sample reveal that the sublattice moments are restricted by the anisotropy of the diruthenium paddle-wheel complexes to the cubic diagonals. Those measurements also suggest that the quantum corrections to the ground state are significant.

Fishman, Randy Scott [ORNL; Campo, Javier [University of Zaragoza, Spain; Vos, Thomas E. [University of Utah; Miller, Joel S. [University of Utah

2012-01-01T23:59:59.000Z

42

Kinetics of Methane Hydrate Decomposition Studied via in Situ Low Temperature X-ray Powder Diffraction  

SciTech Connect

Gas hydrates are known to have a slowed decomposition rate at ambient pressure and temperatures below the melting point of ice termed self-preservation or anomalous preservation. As hydrate exothermically decomposes, gas is released and water of the clathrate cages transforms into ice. Two regions of slowed decomposition for methane hydrate, 180 200 K and 230 260 K, were observed, and the kinetics were studied by in situ low temperature x-ray powder diffraction. The kinetic constants for ice formation from methane hydrate were determined by the Avrami model within each region and activation energies, Ea, were determined by the Arrhenius plot. Ea determined from the data for 180 200 K was 42 kJ/mol and for 230 260 K was 22 kJ/mol. The higher Ea in the colder temperature range was attributed to a difference in the microstructure of ice between the two regions.

Everett, Susan M [ORNL; Rawn, Claudia J [ORNL; Keffer, David J. [University of Tennessee, Knoxville (UTK); Mull, Derek L [ORNL; Payzant, E Andrew [ORNL; Phelps, Tommy Joe [ORNL

2013-01-01T23:59:59.000Z

43

Neutron Diffraction Study of Crystal Structure and Magnetic ...  

Science Conference Proceedings (OSTI)

Abstract Scope, Magnetic refrigeration based on the magnetocaloric effect ... Small and Wide Angle Neutron Scattering for Industrial Applications at HANARO.

44

The early development of neutron diffraction: Science in the wings of the Manhattan Project  

Science Conference Proceedings (OSTI)

Although neutron diffraction was first observed using radioactive decay sources shortly after the discovery of the neutron, it was only with the availability of higher intensity neutron beams from the first nuclear reactors, constructed as part of the Manhattan project, that systematic investigation of Bragg scattering became possible. Remarkably, at a time when the war effort was singularly focused on the development of the atomic bomb, groups working at Oak Ridge and Chicago carried out key measurements and recognized the future utility of neutron diffraction quite independent of its contributions to the measurements of nuclear cross sections. Ernest O. Wollan, Lyle B. Borst, and Walter H. Zinn were all able to observe neutron diffraction in 1944 using the X-10 graphite reactor and the CP-3 heavy water reactor.

Mason, Thom [ORNL; Gawne, Timothy J [ORNL; Nagler, Stephen E [ORNL; Nestor, Margaret Boone {Bonnie} [ORNL; Carpenter, John M [ORNL

2012-01-01T23:59:59.000Z

45

Investigation of Renal Stones by X-ray and Neutron Diffraction  

SciTech Connect

Renal stones were investigated by X-ray diffraction. The obtained results showed only one crystal phase in every sample. With the aim to verify eventual availability of second phase (under 3 volume %) the same renal stones were investigated by neutron diffraction. The neutron spectra proved that additional crystal phase was absent in the renal stones. The obtained results are scientific-practical, in aid of the medicine, especially in the case of renal stone disease.

Baeva, M.; Boianova, A. [Institute of Solid State Physics-BAS, 1784 Sofia (Bulgaria); Beskrovnyi, A. I.; Shelkova, I. [Joint Institute of Nuclear Research, Dubna (Russian Federation)

2007-04-23T23:59:59.000Z

46

Capabilities of the POWDER Instrument | ORNL Neutron Sciences  

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

Capabilities of the POWDER Instrument Capabilities of the POWDER Instrument The scientific areas that may benefit from using the HB-2A instrument are condensed matter physics, chemistry, geology, and material science. Due to its versatility, this instrument can be employed for a large variety of experiments, but it is particularly adapted for determining crystal structures with relatively large unit cells (dmax ≈ 28 Å), as well as complex magnetic structures. Furthermore, studies of phase transitions, thermal expansion, quantitative analysis, and ab-initio structure solution from powder data can be undertaken. A full range of ancillary sample environments can be used to provide a complete control of thermodynamic variables such as temperature, magnetic field, and pressure. The following examples highlight some of the basic features and

47

Phase analysis of metallic plutonium-containing fuel alloys using neutron diffraction  

Science Conference Proceedings (OSTI)

Pulsed neutron powder diffraction studies at IPNS have expanded our understanding of the phases present in Integral Fast Reactor (IFR) metal fuel alloys at temperatures in the range of reactor operating conditions. We report results from the binary alloy (U-10 wt % Zr) and ternary alloys (U-8% Pu-10% Zr) and (U-19% Pu-10% Zr). Determining the role and the location of Zr and Pu in these alloys is considered of fundamental importance for maximizing engineering efficiency. Rietveld profile analysis was utilized to study the phase diagrams. Data were collected at temperatures ranging from 25--650{degree}C. Although the expected U/Pu/Zr phases ({alpha}-U, {beta}-U, {gamma}-U, {delta}-U/Zr/Pu, {zeta}-U/Pu) were observed in appropriate temperature ranges, there were some unexpected results. Relative amounts of all phases at each temperature were calculated from Rietveld scale factors and inferences were made as to the location of zirconium and plutonium, i.e. amounts in each phase, from site occupancies and absorption characteristics of the phases present. Finally, we were able to identify ZrO and ZrO{sub 1-x} inclusion phases in the U-Zr alloy present in very small (0.5--1.0%) amounts. 15 refs., 9 figs., 2 tabs.

Mueller, M.H.; Richardson, J.W. Jr.; Strain, R.V.; Hofman, G.L.

1990-01-01T23:59:59.000Z

48

X-Ray and Neutron Diffraction - Programmaster.org  

Science Conference Proceedings (OSTI)

Oct 20, 2010 ... Strain Determination in Nanoscale Microelectronic Materials Using X-Ray Diffraction: Conal Murray1; 1IBM T.J. Watson Research Center

49

Neutron diffraction measurements of residual stresses in friction stir welding: a review  

Science Conference Proceedings (OSTI)

Significant amounts of residual stresses are often generated during welding and result in critical degradation of the structural integrity and performance of components. Neutron diffraction has become a well established technique for the determination of residual stresses in welds because of the unique deep penetration, three-dimensional mapping capability, and volume averaged bulk measurements characteristic of the scattering neutron beam. Friction stir welding has gained prominence in recent years. The authors reviewed a number of neutron diffraction measurements of residual stresses in friction stir welds and highlighted examples addressing how the microstructures and residual stresses are correlated with each other. An example of in situ neutron diffraction measurement result shows the evolution of the residual stresses during welding.

Woo, Wan Chuck [ORNL; Feng, Zhili [ORNL; Wang, Xun-Li [ORNL; David, Stan A [ORNL

2011-01-01T23:59:59.000Z

50

Peak-shape functions for Neutron Time of Flight  

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

(Draft)-dec. 2003 Introduction A reorganization of the subroutines calculating the peak shape function and derivatives for time of flight neutron powder diffraction has been...

51

Diffraction Analysis of Ball Milled Platinum Based Powders (Pt-ZrO2)  

Science Conference Proceedings (OSTI)

... series of powder samples with different amount of ZrO2 and ball milling time were examined by the synchrotron radiation at Brookhaven National Laboratory.

52

Structure-Function Analysis of Edible FatsChapter 3 Powder X-ray Diffraction of Triglycerides in the Study of Polymorphism  

Science Conference Proceedings (OSTI)

Structure-Function Analysis of Edible Fats Chapter 3 Powder X-ray Diffraction of Triglycerides in the Study of Polymorphism Methods and Analyses eChapters Food Science & Technology Health - Nutrition - Biochemistry Processing Methods - An

53

Electrochemical and in situ neutron diffraction investigations of La-Ni-Al-H alloys  

DOE Green Energy (OSTI)

Li/metal hydride batteries are a strong contender to replace Ni/Cd batteries. Since the role of alloying components is not yet understood, a combination of electrochemical and neutron diffraction techniques has been designed to investigate metal hydrides. In this work, several Al-substituted LaNi{sub 5} alloys were investigated for their specific capacity (measured by mAh/La and symbolized by x in LaNi{sub 5-y}Al{sub y}H{sub x}), impedance, and cycling stability. Neutron diffraction was used to study the electrochemically induced phase transformation and structure change during charge/discharge.

Peng, W. [Illinois Institute of Technology (United States); Redey, L.; Vissers, D.R.; Myles, K.M.; Carpenter, J.; Richardson; Burr, G. [Argonne National Lab., IL (United States)

1996-05-01T23:59:59.000Z

54

Electrochemical and neutron diffraction measurements of PdD{sub x} cathodes  

DOE Green Energy (OSTI)

Potentiometric and in-situ neutron diffraction measurements have been carried out on PdD{sub x} cathodes in LiOD-saturated D{sub 2}O solution. Open-circuit potentials of the PdD{sub x} electrode after interruption of high-intensity cathodic currents (300--500 mA/cm{sup 2}) showed a more negative potential ({epsilon} = 1010 mV, measured against a Hg/HgO reference electrode) than that expected from the literature. The anomalous potentials were observed for about 10--20 min after current interruption at x > 0.7 concentrations of deuterium. This phenomenon may indicate a metastable phase of the Pd-D system, which may be detected by neutron diffraction. In-situ neutron diffraction measurements, so far, have indicated only the evolution of the known {alpha} and {beta} phases of PdD{sub x}. Successful neutron diffraction measurements in electrochemical cells suggest the viability of this technique for in-situ investigations of metal-hydride battery electrodes in experiments when heavy-water electrolyte is used to model the MH{sub 2}/H{sub 2}O electrode.

Redey, L.; Myles, K.M.; Rotella, F.J.; Richardson, J.W. Jr.; Felcher, G.P.; Hitterman, R.L.; Kleb, R.

1991-12-31T23:59:59.000Z

55

diffraction  

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

appear in different places because they correspond to waves of different wavelength. A classical demonstration of diffraction that more closely resembles some high-energy...

56

Quantitative determination of mineral composition by powder x-ray diffraction  

DOE Patents (OSTI)

An external standard intensity ratio method is used for quantitatively determining mineralogic compositions of samples by x-ray diffraction. The method uses ratios of x-ray intensity peaks from a single run. Constants are previously determined for each mineral which is to be quantitatively measured. Ratios of the highest intensity peak of each mineral to be quantified in the sample and the highest intensity peak of a reference mineral contained in the sample are used to calculate sample composition.

Pawloski, G.A.

1984-08-10T23:59:59.000Z

57

Quantitative determination of mineral composition by powder X-ray diffraction  

DOE Patents (OSTI)

An external standard intensity ratio method is used for quantitatively determining mineralogic compositions of samples by x-ray diffraction. The method uses ratios of x-ray intensity peaks from a single run. Constants are previously determined for each mineral which is to be quantitatively measured. Ratios of the highest intensity peak of each mineral to be quantified in the sample and the highest intensity peak of a reference mineral contained in the sample are used to calculate sample composition.

Pawloski, Gayle A. (Livermore, CA)

1986-01-01T23:59:59.000Z

58

In-Situ Studies of Intercritically Austempered Ductile Iron Using Neutron Diffraction  

Science Conference Proceedings (OSTI)

Intercritically austempered ductile irons hold promise for applications requiring fatigue durability, excellent castability, low production energy requirements, reduced greenhouse gas emissions and excellent machinability. In the present study, four different ductile iron alloys, containing manganese and nickel as the primary austenite-stabilizing elements, were heat treated to obtain different quantities of austenite in the final microstructure. This paper reports the microstructures and phases present in these alloys. Further, lattice strains and diffraction elastic constants in various crystallographic directions and the transformation characteristics of the austenite as a function of applied stress were determined using in-situ loading with neutron diffraction at the second generation Neutron Residual Stress Facility (NRSF2) at the High Flux Isotope Reactor (HFIR) at Oak Ridge National Laboratory (ORNL).

Druschitz, Alan [University of Alabama, Birmingham; Aristizabal, Ricardo [University of Alabama, Birmingham; Druschitz, Edward [University of Alabama, Birmingham; Hubbard, Camden R [ORNL; Watkins, Thomas R [ORNL; Walker, Larry R [ORNL; Ostrander, M [Rex Heat Treat, Anniston, AL

2012-01-01T23:59:59.000Z

59

Investigation of surface structures by powder diffraction : a differential pair distribution function study on arsenate sorption on ferrihydrite.  

SciTech Connect

Differential pair distribution function (d-PDF) analysis of high energy powder X-ray diffraction data was carried out on 2-line ferrihydrite nanoparticles with arsenate oxyanions adsorbed on the surface to investigate the binding mechanism. In this analysis, a PDF of ferrihydrite is subtracted from a PDF of ferrihydrite with arsenate sorbed on the surface, leaving only correlations from within the surface layer and between the surface and the particle. As-O and As-Fe correlations were observed at 1.68 and 3.29 {angstrom}, respectively, in good agreement with previously published EXAFS data, confirming a bidentate binuclear binding mechanism. Further peaks are observed in the d-PDF which are not present in EXAFS, corresponding to correlations between As and O in the particle and As-2nd Fe.

Harrington, R.; Hausner, D. B.; Bhandari, N.; Strongin, D. R.; Chapman, K. W.; Chupas, P. J.; Middlemiss, D. S.; Grey, C. P.; Parise, J. B.; X-Ray Science Division; Stony Brook Univ.; Temple Univ.

2010-01-01T23:59:59.000Z

60

Neutron diffraction study of monoclinic brannerite-type CoV{sub 2}O{sub 6}  

Science Conference Proceedings (OSTI)

A variable-temperature powder neutron diffraction study of the monoclinic brannerite-type CoV{sub 2}O{sub 6} (space group C2/m, a=9.2531(2), b=3.5040(1), c=6.6201(1) A and {beta}=111.617(1) Degree-Sign at 300 K) is reported. No structural transition is observed down to 4 K, but a magnetostriction accompanying antiferromagnetic order at T{sub N}=15 K is discovered. Antiferromagnetic order observed below T{sub N} has an a Multiplication-Sign b Multiplication-Sign 2c supercell in which Co{sup 2+} moments of magnitude 4.77(4) {mu}{sub B} at 4 K lie in the ac plane and are ferromagnetically coupled within chains of edge-sharing CoO{sub 6} octahedra parallel to b. Ferromagnetic chains are coupled antiferromagnetically to neighbouring chains in the a and c directions, and a model for the interchain order in the reported 1/3 magnetization plateau region is proposed. - Graphical abstract: Antiferromagnetic order of Co{sup 2+} moments in monoclinic brannerite type CoV2O6 results in a magnetostriction at the 15 K Neel transition. An alternative coupling between ferromagnetic chains is proposed to account for a 1/3 magnetization plateau in this material. Highlights: Black-Right-Pointing-Pointer Variable-temperature powder neutron diffraction study of the monoclinic brannerite-type CoV{sub 2}O{sub 6} is reported. Black-Right-Pointing-Pointer Magnetostriction accompanying antiferromagnetic order at T{sub N}=15 K in monoclinic CoV{sub 2}O{sub 6} is discovered. Black-Right-Pointing-Pointer Antiferromagnetic order in a Multiplication-Sign b Multiplication-Sign 2c supercell of CoV{sub 2}O{sub 6} is determined. Black-Right-Pointing-Pointer Model for spin order in the reported 1/3 magnetization plateau of CoV{sub 2}O{sub 6} is proposed.

Markkula, Mikael; Arevalo-Lopez, Angel M. [Centre for Science at Extreme Conditions and School of Chemistry, University of Edinburgh, Mayfield Road, Edinburgh EH9 3JZ (United Kingdom); Paul Attfield, J., E-mail: j.p.attfield@ed.ac.uk [Centre for Science at Extreme Conditions and School of Chemistry, University of Edinburgh, Mayfield Road, Edinburgh EH9 3JZ (United Kingdom)

2012-08-15T23:59:59.000Z

Note: This page contains sample records for the topic "neutron powder diffraction" from the National Library of EnergyBeta (NLEBeta).
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they are not comprehensive nor are they the most current set.
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61

The catalytic mechanism of an aspartic proteinase explored with neutron and X-ray diffraction  

DOE Green Energy (OSTI)

Hydrogen atoms play key roles in enzyme mechanism, but as this study shows, even high-quality X-ray data to a resolution of 1 {angstrom} cannot directly visualize them. Neutron diffraction, however, can locate deuterium atoms even at resolutions around 2 {angstrom}. Both neutron and X-ray diffraction data have been used to investigate the transition state of the aspartic proteinase endothiapepsin. The different techniques reveal a different part of the story, revealing the clearest picture yet of the catalytic mechanism by which the enzyme operates. Room temperature neutron and X-ray diffraction data were used in a newly developed joint refinement software package to visualize deuterium atoms within the active site of the enzyme when a gem-diol transition state analogue inhibitor is bound at the active site. These data were also used to estimate their individual occupancy, while analysis of the differences between the bond lengths of the catalytic aspartates was performed using atomic resolution X-ray data. The two methods are in agreement on the protonation state of the active site with a transition state analogue inhibitor bound confirming the catalytic mechanism at which the enzyme operates.

Kovalevsky, Andrey [Los Alamos National Laboratory (LANL); Erskine, Peter T. [University of Southampton, England; Cooper, Jon [University of Southampton, England

2008-01-01T23:59:59.000Z

62

neutron diffraction  

Science Conference Proceedings (OSTI)

... Page 7. PBR (NG1) at the NCNR one of a handful globally buried magnetism nuclear contrast wide variety of science also Asterix at LANL

2011-11-14T23:59:59.000Z

63

Time-of-flight neutron diffraction study of bovine [gamma]-chymotrypsin at the Protein Crystallography Station  

SciTech Connect

The overarching goal of this research project is to determine, for a subset of proteins, exact hydrogen positions using neutron diffraction, thereby improving H-atom placement in proteins so that they may be better used in various computational methods that are critically dependent upon said placement. In order to be considered applicable for neutron diffraction studies, the protein of choice must be amenable to ultrahigh-resolution X-ray crystallography, be able to form large crystals (1 mm{sup 3} or greater) and have a modestly sized unit cell (no dimension longer than 100 {angstrom}). As such, {gamma}-chymotrypsin is a perfect candidate for neutron diffraction. To understand and probe the role of specific active-site residues and hydrogen-bonding patterns in {gamma}-chymotrypsin, neutron diffraction studies were initiated at the Protein Crystallography Station (PCS) at Los Alamos Neutron Science Center (LANSCE). A large single crystal was subjected to H/D exchange prior to data collection. Time-of-flight neutron diffraction data were collected to 2.0 {angstrom} resolution at the PCS with 85% completeness. Here, the first time-of-flight neutron data collection from {gamma}-chymotrypsin is reported.

Lazar, Louis M.; Fisher, S. Zoe; Moulin, Aaron G.; Kovalevsky, Andrey; Novak, Walter R.P.; Langan, Paul; Petsko, Gregory A.; Ringe, Dagmar (Brandeis); (LANL)

2012-02-06T23:59:59.000Z

64

Structure of molten Al and eutectic Al-Si alloy studied by neutron diffraction  

Science Conference Proceedings (OSTI)

The structure of molten eutectic Al87.8Si12.2 alloy has been studied by neutron diffraction during a temperature cycle. For comparison measurements were performed on pure molten Al. The measurements show that the alloy after heating above the liquidus contains particles of two kinds, aluminum-rich and silicon-rich. The silicon-rich particles are partly dissolved after a further heating. Earlier published data obtained by the ?-ray absorption technique of the density of the molten eutectic AlSi alloy had demonstrated the existence of two temperatures above the liquidus temperature: A dissolution temperature Td, at which the microstructure of the melt inherited from the ingot starts to dissolve and a branching temperature, Tb, at which the melt reaches a fully mixed state. The highest temperature that was possible to reach during the neutron experiments lies between Td and Tb. The obtained results support these conclusions that molten alloys after melting are inhomogeneous up to a temperature well above the liquidus. Moreover, the difference in shape between the static structure factors measured by neutron and X-ray diffraction on molten aluminum is observed and is found to be more accentuated and to extend to larger wavevectors than in earlier works.

Dahlborg, U. [University of Rouen; Kramer, Matthew J. [Ames Laboratory; Besser, M. [Ames Laboratory; Morris, J. R. [Oak Ridge National Laboratory; Calvo-Dahlborg, M. [University of Rouen

2012-11-24T23:59:59.000Z

65

Neutron diffraction of alpha, beta and gamma cyclodextrins: hydrogen bonding patterns  

DOE Green Energy (OSTI)

Cyclodextrins (CD's) have proved useful as model systems. They are torus-shaped molecules composed of six (..cap alpha..), seven (..beta..) or eight (..gamma..) (1 to 4) linked glucoses. In order to understand the hydrogen bonding in these enzyme models, neutron diffraction data were collected to unambiguously determine the hydrogen atom positions, which could not be done from x-ray diffraction data alone. ..cap alpha..-CD has been shown to have two different structures with well-defined hydrogen bonds, one tense and the other relaxed. An induced-fit-like mechanism for ..cap alpha..-CD complex formation has been proposed. Circular and infinite chain hydrogen bond networks have also been observed, which are energetically favored due to the cooperative effect. ..beta..-CD with a disordered water structure possesses an unusual flip-flop hydrogen bonding system of the type O-H . . . H-O representing an equilibrium between two states: O-H . . . O and O . . . H-O. ..gamma..-CD has now been studied at room temperature by neutron diffraction and also possesses the flip-flop hydrogen bond. Data have been collected to 0.62 A resolution at the ORNL reactor (HFIR). 235 atoms have been refined to R=0.077 for 4816 observed reflections (I > sigma) and R=0.099 for all 5864 reflections. Low temperature neutron data will be collected. This study demonstrates that hydrogen bonds are operative in disordered systems and display dynamics even in the solid state. 17 references, 1 figure, 2 tables.

Hingerty, B.; Betzel, C.; Saenger, W.

1984-01-01T23:59:59.000Z

66

NEUTRON AND SYNCHROTRON X-RAY FIBER DIFFRACTION STUDIES OF CELLULOSE POLYMORPHS.  

DOE Green Energy (OSTI)

Although the crystalline nature of cellulose has been one of most studied structural problems in polymer science there remain many open questions. Cellulose is a polymer formed by (1-4)-linked {beta}-D-glucosyl residues that are alternately rotated by 180o along the polymer axis to form flat ribbon-like chains. Each glucosyl unit bears three hydroxyl groups, one an hydroxymethyl group. It has been long recognized that these hydroxyl groups and their ability to bond via hydrogen bonding not only play a major role in directing how the crystal structure of cellulose forms but also in governing important physical properties of cellulose materials. Through the development of new techniques we have been able to prepare fiber samples of cellulose with exceptionally high order. The quality of these samples is allowing us to exploit the unique properties of synchrotron X-ray and neutron sources in order to collect diffraction data to near atomic resolution. Synchrotron X-rays are used to provide accurate crystallographic parameters for C and O atoms. However, because of the relatively weak scattering power of H atoms for X-rays, neutrons are used to determine H atom parameters. We have developed methods for replacing labile H atoms with D, without any loss in crystalline perfection. Deuterated fibers can diffract neutrons with intensities that are substantially different from the intensities diffracted from hydrogenated fibers. These differences, along with the phases calculated from the C and O positions determined in our X-ray studies, are used to calculate Fourier difference syntheses in which density associated with labile hydrogen atoms is imaged. The unprecedented high resolution of these data is revealing new information on cellulose structure and hydrogen bonding.

Los Alamos National Laboratory

2001-01-01T23:59:59.000Z

67

Residual stress determination in an overlay dissimilar welded pipe by neutron diffraction  

Science Conference Proceedings (OSTI)

Residual stresses were determined through the thickness of a dissimilar weld overlay pipe using neutron diffraction. The specimen has a complex joining structure consisting of a ferritic steel (SA508), austenitic steel (F316L), Ni-based consumable (Alloy 182), and overlay of Ni-base superalloy (Alloy 52M). It simulates pressurized nozzle components, which have been a critical issue under the severe crack condition of nuclear power reactors. Two neutron diffractometers with different spatial resolutions have been utilized on the identical specimen for comparison. The macroscopic 'stress-free' lattice spacing (d{sub o}) was also obtained from both using a 2-mm width comb-like coupon. The results show significant changes in residual stresses from tension (300-400 MPa) to compression (-600 MPa) through the thickness of the dissimilar weld overlay pipe specimen.

Woo, Wan Chuck [ORNL; Em, Vyacheslav [Korea Atomic Energy Research Institute; Hubbard, Camden R [ORNL; Lee, Ho-Jin [Korea Atomic Energy Research Institute; Park, Kwang Soo [Doosan Heavy Industries & Construction

2011-01-01T23:59:59.000Z

68

THE CRYSTAL STRUCTURE OF THORIUM AND ZIRCONIUM DIHYDRIDES BY X-RAY AND NEUTRON DIFFRACTION  

DOE Green Energy (OSTI)

Thorium forms a tetragonal lower hydride of composition ThH{sub 2}. The hydrides ThH{sub 2}, ThD{sub 2} and ZrD{sub 2} have been studied by neutron diffraction in order that hydrogen positions could be determined. The hydrides are isomorphous, and have a deformed fluorite structure. Metal-hydrogen distances in thorium hydride are unusually large, as in UH{sub 3}. Thorium and zirconium scattering amplitudes and a revised scattering amplitude for deuterium are reported.

Rundle, R.E.; Shull, C.G.; Wollan, E.O.

1951-04-20T23:59:59.000Z

69

Cage occupancies in the high pressure structure H methane hydrate: A neutron diffraction study  

SciTech Connect

A neutron diffraction study was performed on the CD{sub 4}: D{sub 2}O structure H clathrate hydrate to refine its CD{sub 4} fractional cage occupancies. Samples of ice VII and hexagonal (sH) methane hydrate were produced in a Paris-Edinburgh press and in situ neutron diffraction data collected. The data were analyzed with the Rietveld method and yielded average cage occupancies of 3.1 CD{sub 4} molecules in the large 20-hedron (5{sup 12}6{sup 8}) cages of the hydrate unit cell. Each of the pentagonal dodecahedron (5{sup 12}) and 12-hedron (4{sup 3}5{sup 6}6{sup 3}) cages in the sH unit cell are occupied with on average 0.89 and 0.90 CD{sub 4} molecules, respectively. This experiment avoided the co-formation of Ice VI and sH hydrate, this mixture is more difficult to analyze due to the proclivity of ice VI to form highly textured crystals, and overlapping Bragg peaks of the two phases. These results provide essential information for the refinement of intermolecular potential parameters for the water methane hydrophobic interaction in clathrate hydrates and related dense structures.

Tulk, Christopher A [ORNL; Klug, Dennis D [National Research Council of Canada; Moreira Dos Santos, Antonio F [ORNL; Karotsis, Georgios [ORNL; Guthrie, Malcolm [Carnegie Institution of Washington; Molaison, Jamie J [ORNL; Pradhan, Neelam [ORNL

2012-01-01T23:59:59.000Z

70

In-situ time-of-flight neutron diffraction of ErD2 (beta phase) formation during D2 loading.  

DOE Green Energy (OSTI)

In an effort to better understand the structural changes occurring during hydrogen loading of erbium target materials, we have performed D{sub 2} loading of erbium metal (powder) with simultaneous neutron diffraction analysis. This experiment tracked the conversion of Er metal to the {alpha} erbium deuteride (solid-solution) phase and then on to the {beta} (fluorite) phase. Complete conversion to ErD{sub 2.0} was accomplished at 10 Torr D{sub 2} pressure with deuterium fully occupying the tetrahedral sites in the fluorite lattice. Increased D{sub 2} pressure (up to 500 Torr at 450 C) revealed {approx}10 % deuterium occupation of the octahedral sites. Subsequent vacuum pumping of the sample at 450 C removed octahedral site occupancy while maintaining tetrahedral deuterium occupancy, thereby yielding stoichiometric ErD{sub 2.0} {beta} phase.

Browning, James Frederick (Oak Ridge National Laboratory, Oak Ridge, TN); Llobet, Anna (Los Alamos National Laboratory, Los Alamos, NM); Snow, Clark Sheldon; Rodriguez, Mark Andrew; Wixom, Ryan R.

2008-06-01T23:59:59.000Z

71

Powder Diffraction with Proteins  

Science Conference Proceedings (OSTI)

... Sum up similar scans (typically chi2 statistic, CC also useful) ... TotalCrystallography Large software investment http://fable.sourceforge.net ...

2013-06-07T23:59:59.000Z

72

Chem-prep PZT 95/5 for neutron generator applicatios : powder preparation characterization utilizing design of experiments.  

Science Conference Proceedings (OSTI)

Niobium doped PZT 95/5 (lead zirconate-lead titanate) is the material used in voltage bars for all ferroelectric neutron generator power supplies. In June of 1999, the transfer and scale-up of the Sandia Process from Department 1846 to Department 14192 was initiated. The laboratory-scale process of 1.6 kg has been successfully scaled to a production batch quantity of 10 kg. This report documents efforts to characterize and optimize the production-scale process utilizing Design of Experiments methodology. Of the 34 factors identified in the powder preparation sub-process, 11 were initially selected for the screening design. Additional experiments and safety analysis subsequently reduced the screening design to six factors. Three of the six factors (Milling Time, Media Size, and Pyrolysis Air Flow) were identified as statistically significant for one or more responses and were further investigated through a full factorial interaction design. Analysis of the interaction design resulted in developing models for Powder Bulk Density, Powder Tap Density, and +20 Mesh Fraction. Subsequent batches validated the models. The initial baseline powder preparation conditions were modified, resulting in improved powder yield by significantly reducing the +20 mesh waste fraction. Response variation analysis indicated additional investigation of the powder preparation sub-process steps was necessary to identify and reduce the sources of variation to further optimize the process.

Lockwood, Steven John; Rodman-Gonzales, Emily Diane; Voigt, James A.; Moore, Diana Lynn

2003-07-01T23:59:59.000Z

73

NEUTRON DIFFRACTION STUDY OF A NON-STOICHIOMETRIC Ni-Mn-Ga MSM ALLOY  

SciTech Connect

The structure and chemical order of a Heusler alloy of non-stoichiometric composition Ni-Mn-Ga were studied using constant-wavelength (1.538 ) neutron diffraction at 363K and the diffraction pattern was refined using the FullProf software. At this temperature the structure is austenite (cubic) with Fm-3m space group and lattice constant of a = 5.83913(4) [ ]. The chemical order is of critical importance in these alloys, as Mn becomes antiferromagnetic when the atoms are closer than the radius of the 3d shell. In the studied alloy the refinement of the site occupancy showed that the 4b (Ga site) contained as much as 22% Mn; that significantly alters the distances between the Mn atoms in the crystal and, as a result, also the exchange energy between some of the Mn atoms. Based on the refinement, the composition was determined to be Ni1.91Mn1.29Ga0.8

Ari-Gur, Pnina [Western Michigan University; Garlea, Vasile O [ORNL

2013-01-01T23:59:59.000Z

74

The magnetic and crystal structures of Sr2IrO4: A neutron diffraction study  

SciTech Connect

We report a single-crystal neutron diffraction study of the layered Sr2IrO4. This work unambigu- ously determines the magnetic and crystal structures, and reveals that the spin orientation rigidly tracks the staggered rotation of the IrO6 octahedra in Sr2IrO4. The long-range antiferromagnetic order has a canted spin configuration with an ordered moment of 0.208(3) B/Ir site within the basal plane; a detailed examination of the spin canting yields 0.202(3) and 0.049(2) B/site for the a-axis and the b-axis, respectively. It is intriguing that forbidden nuclear reflections of space group I41/acd are also observed in a wide temperature range from 4 K to 600 K, which suggests a reduced crystal structure symmetry. This neutron scattering work provides a direct, well-refined experimen- tal characterization of the magnetic and crystal structures that are crucial to the understanding of the unconventional magnetism existent in this unusual magnetic insulator.

Ye, Feng [ORNL; Chi, Songxue [ORNL; Chakoumakos, Bryan C [ORNL; Fernandez-Baca, Jaime A [ORNL; Qi, Tongfei [University of Kentucky; Cao, Gang [University of Kentucky

2013-01-01T23:59:59.000Z

75

In-Situ Neutron Diffraction Study of Recrystallization Kinetics in a ...  

Science Conference Proceedings (OSTI)

Symposium, Neutron and X-Ray Studies of Advanced Materials IV ... engineering materials difffractometer from Spallation Neutron Source [SNS] and at HIPPO...

76

Thermal expansion and decomposition of jarosite: a high-temperature neutron diffraction study  

DOE Green Energy (OSTI)

The structure of deuterated jarosite, KFe{sub 3}(SO{sub 4}){sub 2}(OD){sub 6}, was investigated using time-of-flight neutron diffraction up to its dehydroxylation temperature. Rietveld analysis reveals that with increasing temperature, its c dimension expands at a rate {approx}10 times greater than that for a. This anisotropy of thermal expansion is due to rapid increase in the thickness of the (001) sheet of [Fe(O,OH){sub 6}] octahedra and [SO{sub 4}] tetrahedra with increasing temperature. Fitting of the measured cell volumes yields a coefficient of thermal expansion, a = a{sub 0} + a{sub 1} T, where a{sub 0} = 1.01 x 10{sup -4} K{sup -1} and a{sub 1} = -1.15 x 10{sup -7} K{sup -2}. On heating, the hydrogen bonds, O1{hor_ellipsis}D-O3, through which the (001) octahedral-tetrahedral sheets are held together, become weakened, as reflected by an increase in the D{hor_ellipsis}O1 distance and a concomitant decrease in the O3-D distance with increasing temperature. On further heating to 575 K, jarosite starts to decompose into nanocrystalline yavapaiite and hematite (as well as water vapor), a direct result of the breaking of the hydrogen bonds that hold the jarosite structure together.

Xu, Hongwu [Los Alamos National Laboratory; Zhao, Yusheng [Los Alamos National Laboratory; Vogel, Sven C [Los Alamos National Laboratory; Hickmott, Donald D [Los Alamos National Laboratory; Daemen, Luke L [Los Alamos National Laboratory; Hartl, Monika A [Los Alamos National Laboratory

2009-01-01T23:59:59.000Z

77

Diffraction at HFIR  

Science Conference Proceedings (OSTI)

Of the planned suite of powder and single-crystal diffractometers for the HFIR, only two are currently operating, the Neutron Residual Stress Mapping Facility (NRSF2) diffractometer, and the Wide Angle Neutron Diffractometer (WAND). The NSRF2 was recently upgraded and is available to external users via the High Temperature Materials Laboratory (HTML) User Program for studies of stress, texture and phase mapping. The WAND is a flat-cone geometry diffractometer equipped with a curve 1-D PSD, suitable for high intensity powder diffraction (e.g., kinetics, high pressure) and diffuse scattering studies of single-crystals. A rebuild of the old HFIR powder diffractometer, originally located at HB-4 station is now underway, and is expected to begin commissioning by summer 2008. This instrument has a Debye-Scherrer geometry, with a detector bank consisting of 44 3He tubes each with 6' Soller collimators. A four-circle single-crystal diffractometer is located at the HB-3A station, and is slowly being brought back to life after the long hiatus connected to the reactor upgrade. A Letter of Intent to build a quasi-Laue diffractometer, called IMAGINE, in the HFIR Cold Guide Hall has been presented to and endorsed by the Neutron Scattering Science Advisory Committee.

Chakoumakos, Bryan C [ORNL; Fernandez-Baca, Jaime A [ORNL; Garlea, Vasile O [ORNL; Hubbard, Camden R [ORNL; Wang, Xun-Li [ORNL

2008-01-01T23:59:59.000Z

78

Neutron Diffraction Residual Strain Tensor Measurements Within The Phase IA Weld Mock-up Plate P-5  

SciTech Connect

Oak Ridge National Laboratory (ORNL) has worked with NRC and EPRI to apply neutron and X-ray diffraction methods to characterize the residual stresses in a number of dissimilar metal weld mockups and samples. The design of the Phase IA specimens aimed to enable stress measurements by several methods and computational modeling of the weld residual stresses. The partial groove in the 304L stainless steel plate was filled with weld beads of Alloy 82. A summary of the weld conditions for each plate is provided in Table 1. The plates were constrained along the long edges during and after welding by bolts with spring-loaded washers attached to the 1-inch thick Al backing plate. The purpose was to avoid stress relief due to bending of the welded stainless steel plate. The neutron diffraction method was one of the methods selected by EPRI for non-destructive through thickness strain and stress measurement. Four different plates (P-3 to P-6) were studied by neutron diffraction strain mapping, representing four different welding conditions. Through thickness neutron diffraction strain mappings at NRSF2 for the four plates and associated strain-free d-zero specimens involved measurement along seven lines across the weld and at six to seven depths. The mountings of each plate for neutron diffraction measurements were such that the diffraction vector was parallel to each of the three primary orthogonal directions of the plate: two in-plane directions, longitudinal and transverse, and the direction normal to the plate (shown in left figure within Table 1). From the three orthogonal strains for each location, the residual stresses along the three plate directions were calculated. The principal axes of the strain and stress tensors, however, need not necessarily align with the plate coordinate system. To explore this, plate P-5 was selected for examination of the possibility that the principal axes of strain are not along the sample coordinate system axes. If adequate data could be collected the goal would be to determine the strain tensor's orientation and magnitude of strain along each principle axis direction.

Hubbard, Camden R [ORNL

2011-09-01T23:59:59.000Z

79

The Manuel Lujan, Jr. Neutron Scattering Center LANSCE experiment reports 1989 run cycle  

SciTech Connect

This report contains a listing and description of experiments carried on at the LANSCE neutron scattering facility in the following areas: High Density Powder Diffraction; Neutron Powder Diffractometer, (NPD); Single Crystal Diffractometer, (SCD); Low-Q Diffractometer, (LQD); Surface Profile Analysis Reflectometer, (SPEAR); Filter Difference Spectrometer, (FDS); and Constant-Q Spectrometer.

Hyer, D.K.; DiStravolo, M.A. (comps.)

1990-10-01T23:59:59.000Z

80

A combined solid-state NMR and synchrotron x-ray diffraction powder study on the structure of the antioxidant(+)-catechin 4.5 hydrate.  

DOE Green Energy (OSTI)

Analyses combining X-ray powder diffraction (XRD) and solid-state NMR (SSNMR) data can now provide crystal structures in challenging powders that are inaccessible by traditional methods. The flavonoid catechin is an ideal candidate for these methods, as it has eluded crystallographic characterization despite extensive study. Catechin was first described nearly two centuries ago, and its powders exhibit numerous levels of hydration. Here, synchrotron XRD data provide all heavy-atom positions in (+)-catechin 4.5-hydrate and establish the space group as C2. SSNMR data ({sup 13}C tensor and {sup 1}H/{sup 13}C correlation) complete the conformation by providing catechin's five OH hydrogen orientations. Since 1903, this phase has been erroneously identified as a 4.0 hydrate, but XRD and density data establish that this discrepancy is due to the facile loss of the water molecule located at a Wyckoff special position in the unit cell. A final improvement to heavy-atom positions is provided by a geometry optimization of bond lengths and valence angles with XRD torsion angles held constant. The structural enhancement in this final structure is confirmed by the significantly improved fit of computed {sup 13}C tensors to experimental data.

Harper, J. K.; Doebbler, J. A.; Jaccques, E.; Grant, D. M.; Von Dreele, R. B.; Univ. of Utah

2010-03-10T23:59:59.000Z

Note: This page contains sample records for the topic "neutron powder diffraction" 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

QUANTITATIVE X-RAY POWDER DIFFRACTION ANALYSES OF CLAYS USING AN ORIENTING INTERNAL STANDARD AND PRESSED DISKS OF BULK SHALE SAMPLES  

E-Print Network (OSTI)

Abstraet--Quantitative analysis of clay minerals by X-ray powder diffraction requires oriented clays in order to increase detection limits of the analyses. This is achieved commonly either by smear or sedimentation techniques; however, these techniques can lead to poor analytical precision when used with an internal standard because they often produce non-homogeneous internal standard-clay mineral mixtures. Compaction of bulk shale material at 8000 psi in an hydraulic press produces preferred orientations comparable to that produced by smear or sedimentation. When used with a suitable platy internal standard which provides an estimate of clay mineral preferred orientation, excellent analytical precision is achieved routinely. Several lines of experimental evidence indicate that 1-5 /tm MoS2 is an ideal orienting internal standard for use with compaction mounts.

R. D. Cody; G. L. Thompson

1976-01-01T23:59:59.000Z

82

Stress-induced martensitic transformations in NiTi and NiTi-TiC composites investigated by neutron diffraction  

SciTech Connect

Superelastic NiTi (51.0 at% Ni) with 0, 10 and 20 vol% TiC particles were deformed under uniaxial compression as neutron diffraction spectra were simultaneously obtained. The experiments yielded in-situ measurements of the thermoelastic stress-induced transformation. A detailed Rietveld determination is made of the phase fractions and the evolving strains in the reinforcing TiC particles and the austenite as it transforms to martensite on loading (and its subsequent back transformation on unloading). These strains are used to shed light on the phenomenon of load transfer in composites where the matrix undergoes a stress-induced phase transformation.

Vaidyanathan, R. [Massachusetts Inst. of Tech., Cambridge, MA (United States). Dept. of Materials Science and Engineering; Bourke, M.A.M. [Los Alamos National Lab., NM (United States); Dunand, D.C. [Northwestern Univ., Evanston, IL (United States)

1998-12-31T23:59:59.000Z

83

CO2 Adsorption to Sub-Single Hydration Layer Montmorillonite Clay Studied by Excess Sorption and Neutron Diffraction  

SciTech Connect

Geologic storage of CO2 requires that the caprock sealing the storage rock is highly impermeable by CO2. Swelling clays, which are important components of caprocks, may react with CO2 under volume change, potentially impacting the seal quality. The interactions of scCO2 with Na saturated montmorillonite clay containing a sub-single layer of water in the interlayer region have been studied by sorption and neutron diffraction techniques. The excess sorption isotherms show maxima at bulk CO2 densities of 0.15 g/cm3, followed by an approximately linear decrease of excess sorption to zero and negative values with increasing CO2 bulk density. Neutron diffraction experiments on the same clay sample measured interlayer spacing and composition. The results show that limited amounts of CO2 are sorbed into the interlayer region, leading to depression of the interlayer peak intensity and an increase of the d(001) spacing by ca. 0.5 . The density of CO2 in the clay pores is relatively stable over a wide range of CO2 pressures at a given temperature, indicating the formation of a clay-CO2 phase. At low pressure increasing CO2 adsorption with decreasing temperature is observed while the high-pressure sorption properties exhibit weak or no temperature dependence. Supercritical fluids, sorption phenomena, carbon dioxide, carbon sequestration, caprock integrity

Rother, Gernot [ORNL; Ilton, Eugene [Pacific Northwest National Laboratory (PNNL); Wallacher, Dirk [Helmholtz-Zentrum Berlin; Hauss, Thomas [Helmholtz-Zentrum Berlin; Schaef, Herbert [Pacific Northwest National Laboratory (PNNL); Qafoku, Odeta [Pacific Northwest National Laboratory (PNNL); Rosso, Kevin M. [Pacific Northwest National Laboratory (PNNL); Felmy, Andrew [Pacific Northwest National Laboratory (PNNL); Krukowski, Elizabeth G [ORNL; Stack, Andrew G [ORNL; Bodnar, Robert J [ORNL

2013-01-01T23:59:59.000Z

84

CO2 Sorption to Subsingle Hydration Layer Montmorillonite Clay Studied by Excess Sorption and Neutron Diffraction Measurements  

SciTech Connect

Geologic storage of CO2 requires that the caprock sealing the storage rock is highly impermeable by CO2. Swelling clays, which are important components of caprocks, may interact with CO2 under volume change, potentially impacting the seal quality. The interactions of scCO2 with Na saturated montmorillonite clay containing a sub-single layer of water in the interlayer region have been studied by sorption and neutron diffraction techniques. The excess sorption isotherms show maxima at bulk CO2 densities of ??0.15 g/cm3, followed by an approximately linear decrease of excess sorption to zero and negative values with increasing CO2 bulk density. Neutron diffraction experiments on the same clay sample measured interlayer spacing and composition. The results show that limited amounts of CO2 are sorbed into the interlayer region, leading to depression of the interlayer peak intensity and an increase of the d(001) spacing by ca. 0.5 . The density of CO2 in the clay pores is relatively stable over a wide range of CO2 pressures at a given temperature, indicating the formation of a clay-CO2 phase. At the excess sorption maximum, increasing CO2 sorption with decreasing temperature is observed while the high-pressure sorption properties exhibit weak temperature dependence.

Rother, Gernot; Ilton, Eugene S.; Wallacher, Dirk; Hauss, Thomas; Schaef, Herbert T.; Qafoku, Odeta; Rosso, Kevin M.; Felmy, Andrew R.; Krukowski, Elizabeth; Stack, Andrew G.; Grimm, Nico; Bodnar, Robert J.

2013-01-15T23:59:59.000Z

85

Neutron Diffraction Study On Gamma To Alpha Phase Transition In Ce0.9th0.1 Alloy  

SciTech Connect

Comprehensive neutron diffraction measurements were performed to study the isostructural {gamma} {leftrightarrow} {alpha} phase transition in Ce{sub 0.9}Th{sub 0.1} alloy. Using Rietveld refinements, we obtained lattice and thermal parameters as a function of temperature. From the temperature slope of the thermal parameters, we determined Debye temperatures {Theta}{sup {gamma}}{sub D} = 133(1) K and {Theta}{sup {alpha}}{sub D} = 140(1) K for the {gamma} phase and the {alpha} phase, respectively. This result implies that the vibrational entropy change is not significant at the {gamma} {leftrightarrow} {alpha} transition, contrary to that from elemental Cerium [Phys. Rev. Lett. 92, 105702, 2004].

Lashley, Jason C1 [Los Alamos National Laboratory; Heffner, Robert H [Los Alamos National Laboratory; Llobet, A [Los Alamos National Laboratory; Darling, T W [U OF NEVADA; Jeong, I K [PUSAN NATL UNIV

2008-01-01T23:59:59.000Z

86

Hidden Superlattice in Tl2(SC6H4S) and Tl2(SeC6H4Se) Solved from Powder X-ray Diffraction  

SciTech Connect

The crystal structures of the isostructural title compounds poly[({mu}-benzene-1,4-dithiolato)dithallium], Tl{sub 2}(SC{sub 6}H{sub 4}S), and poly[({mu}-benzene-1,4-diselenolato)dithallium], Tl{sub 2}(SeC{sub 6}H{sub 4}Se), were solved by simulated annealing from high-resolution synchrotron X-ray powder diffraction. Rietveld refinements of an initial structure with one formula unit per triclinic cell gave satisfactory agreement with the data, but led to a structure with impossibly close non-bonded contacts. A disordered model was proposed to alleviate this problem, but an alternative supercell structure leads to slightly improved agreement with the data. The isostructural superlattice structures were confirmed for both compounds through additional data collection, with substantially better counting statistics, which revealed the presence of very weak superlattice peaks not previously seen. Overall, each structure contains Tl-S or Tl-Se two-dimensional networks, connected by phenylene bridges. The sulfur (or selenium) coordination sphere around each thallium is a highly distorted square pyramid or a 'see-saw' shape, depending upon how many Tl-S or Tl-Se interactions are considered to be bonds. In addition, the two compounds contain pairs of Tl{sup I} ions that interact through a closed-shell 'thallophilic' interaction: in the sulfur compound there are two inequivalent pairs of Tl atoms with Tl-Tl distances of 3.49 and 3.58 {angstrom}, while in the selenium compound those Tl-Tl interactions are at 3.54 and 3.63 {angstrom}.

K Stone; D Turner; M Singh; T Vaid; P Stephens

2011-12-31T23:59:59.000Z

87

Diffraction: Stresses and Structures  

Science Conference Proceedings (OSTI)

Aug 6, 2013 ... O. Advanced Neutron and Synchrotron Studies of Materials: Diffraction: Stresses ... of Newcastle; 2ANSTO; 3European Spallation Source (ESS)

88

Local and average structures of the spin-glass pyrochlore Y2Mo2O7 from neutron diffraction and neutron pair distribution function analysis  

Science Conference Proceedings (OSTI)

The observation of canonical spin-glass behavior in the pyrochlore oxide Y{sub 2}Mo{sub 2}O{sub 7} has been a subject of considerable interest as the original structural studies were interpreted in terms of a well-ordered crystallographic model. It is widely held that the stabilization of the spin-glass state requires some level of positional disorder along with frustration. Recent reports from local probe measurements, extended x-ray-absorption fine structure (EXAFS) and {sup 89}Y NMR, have been interpreted in terms of disorder involving the Mo-Mo distances (EXAFS) and multiple Y sites (NMR). This work reports results from temperature-dependent (15--300 K) neutron diffraction (ND) and neutron pair distribution function studies which can provide from the same data set information on both the average and local structures. The principal findings are that: (1) there is no crystallographic phase transition over the temperature region studied within the resolution of the ND data; (2) the diffraction data are well fitted using a fully ordered model but with large and anisotropic displacement parameters for three of the four atomic sites; (3) the pairwise real-space correlation function G(r) shows clear evidence that the principal source of disorder is associated with the Y-O1 atom pairs rather than the Mo-Mo pairs, in disagreement with the interpretation of the EXAFS results; (4) fits to the G(r) improve significantly when anisotropic displacements for all sites are included; (5) inclusion of a split-site position parameter for O1 improves, slightly, both the G(r) fits and the Rietveld fits to the ND data; and (6) for all models the fits become worse as the temperature decreases and as the fitting range decreases. These results are qualitatively consistent with the {sup 89}Y NMR observations and perhaps recent muon-spin-relaxation studies. The issue of static versus dynamic disorder is not resolved, definitively. An estimate of the distribution of exchange constants due to the disorder is made using spin-dimer analysis and compared with the Saunders-Chalker model for the generation of spin-glass behavior from 'weak' disorder on geometrically frustrated lattices.

Proffen, Thomas Ernst [Los Alamos National Laboratory; Kim, Hyunjeong [Los Alamos National Laboratory; Greedan, John [MCMASTER UNIV; Gout, Delphine [ORNL; Lozano - Gorrin, A D [MCMASTER UNIV; Derahkshan, Shahab [MCMASTER UNIV; Bozin, E [COLUMBIA UNIV; Billinge, S J L [COLUMBIA UNIV

2009-01-01T23:59:59.000Z

89

Development of a Neutron Diffraction Based Experiemental Capability for Investigating Hydraulic Fracturing for EGS-like Conditions  

Science Conference Proceedings (OSTI)

Hydraulic fracturing to enhance formation permeability is an established practice in the Oil & Gas (O&G) industry and is expected to be an enabler for EGS. However, it is rarely employed in conventional geothermal systems and there are significant questions regarding the translation of practice from O&G to both conventional geothermal and EGS applications. Lithological differences(sedimentary versus crystalline rocks, significantly greater formation temperatures and different desired fracture characteristics are among a number of factors that are likely to result in a gap of understanding of how to manage hydraulic fracturing practice for geothermal. Whereas the O&G community has had both the capital and the opportunity to develop its understanding of hydraulic fracturing operations empirically in the field as well through extensive R&D efforts, field testing opportunities for EGS are likely to be minimal due to the high expense of hydraulic fracturing field trials. A significant portion of the knowledge needed to guide the management of geothermal/EGS hydraulic fracturing operations will therefore likely have to come from experimental efforts and simulation. This paper describes ongoing efforts at Oak Ridge National Laboratory (ORNL) to develop an experimental capability to map the internal stresses/strains in core samples subjected to triaxial stress states and temperatures representative of EGS-like conditions using neutron diffraction based strain mapping techniques. This capability is being developed at ORNL\\'s Spallation Neutron Source, the world\\'s most powerful pulsed neutron source and is still in a proof of concept phase. A specialized pressure cell has been developed that permits independent radial and axial fluid pressurization of core samples, with axial flow through capability and a temperature rating up to 300 degrees C. This cell will ultimately be used to hydraulically pressurize EGS-representative core samples to conditions of imminent fracture and map the associated internal strain states of the sample. This will hopefully enable a more precise mapping of the rock material failure envelope, facilitate a more refined understanding of the mechanism of hydraulically induced rock fracture, particularly in crystalline rocks, and serve as a platform for validating and improving fracture simulation codes. The elements of the research program and preliminary strain mapping results of a Sierra White granite sample subjected only to compressive loading will be discussed in this paper.

Polsky, Yarom [ORNL; Anovitz, Lawrence {Larry} M [ORNL; An, Ke [ORNL; Carmichael, Justin R [ORNL; Bingham, Philip R [ORNL; Dessieux Jr, Luc Lucius [ORNL

2013-01-01T23:59:59.000Z

90

Contacts | ORNL Neutron Sciences  

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

Science Points of Contact Science Points of Contact Name Research Area Doug Abernathy Wide Angular-Range Chopper Spectrometer (ARCS). Atomic-scale dynamics at thermal and epithermal energies Ke An Engineering Materials Diffractometer (VULCAN). Residual stress, deformation mechanism of materials, phase transitions/transformation, and in situ/operando neutron diffraction in material systems (e.g., working batteries). John Ankner Liquids Reflectometer (LR). Density profiles normal to the surface at liquid surfaces and liquid interfaces Bryan Chakoumakos Nuclear and magnetic crystal structure systematics and structure-property relationships among inorganic materials, powder and single-crystal neutron and x-ray diffraction methods Leighton Coates Macromolecular Neutron Diffractometer (MaNDi). Protein crystallography, biological structure and function

91

Neutrons  

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

School on Neutron and X-ray Scattering Oak Ridge 10-24 August 2013 John M. Carpenter ANL, ORNLSNS 18 August 2013 2 Neutron Detection How does one detect a neutron? - It is...

92

Diffraction Analysis of Alloys  

Science Conference Proceedings (OSTI)

Feb 18, 2010 ... Neutron and X-Ray Studies of Advanced Materials III : Diffraction Analysis of Alloys .... at the Advanced Photon Source at Argonne National Laboratory in .... pure Zirconium was performed with the D-DIA apparatus at the APS.

93

A high temperature neutron diffraction study of the double perovskite Ba{sub 2}{sup 154}SmMoO{sub 6}  

SciTech Connect

Ba{sub 2}LnMoO{sub 6} double perovskites have been recently shown to display a wide range of interesting magnetic and structural properties; Ba{sub 2}{sup 154}SmMoO{sub 6} exhibits simultaneous antiferromagnetic order and a Jahn-Teller distortion. Here we report a high temperature neutron diffraction study of Ba{sub 2}{sup 154}SmMoO{sub 6} from 353 to 877 K. The results evidence a tetragonal to cubic phase transition at 423 K. Above this temperature the thermal displacement parameters of the oxygen atoms are modelled anisotropically as a result of a transverse vibration of the bridging oxygen. A smooth increase in the cell parameter a is observed with temperature for Ba{sub 2}{sup 154}SmMoO{sub 6}. - Graphical abstract: The high temperature crystal structure of Ba{sub 2}{sup 154}SmMoO{sub 6} evidencing a transverse oxygen vibration. Highlights: Black-Right-Pointing-Pointer A high temperature neutron diffraction study has been performed on an isotopically enriched sample of Ba{sub 2}{sup 154}SmMoO{sub 6}. Black-Right-Pointing-Pointer A cubic-tetragonal phase transition occurs below 423 K. Black-Right-Pointing-Pointer The thermal displacement parameters of the bridging oxygens are modelled anisotropically. Black-Right-Pointing-Pointer There is a transverse vibration of the bridging oxygen.

Wallace, Thomas K. [Department of Chemistry, University of Aberdeen, Meston Walk, Aberdeen AB24 3UE (United Kingdom)] [Department of Chemistry, University of Aberdeen, Meston Walk, Aberdeen AB24 3UE (United Kingdom); Ritter, Clemens [Institut Laue Langevin, 6 rue Jules Horowitz, BP 156, F-38042 Grenoble Cedex 9 (France)] [Institut Laue Langevin, 6 rue Jules Horowitz, BP 156, F-38042 Grenoble Cedex 9 (France); Mclaughlin, Abbie C., E-mail: a.c.mclaughlin@abdn.ac.uk [Department of Chemistry, University of Aberdeen, Meston Walk, Aberdeen AB24 3UE (United Kingdom)

2012-12-15T23:59:59.000Z

94

WAND: Wide-Angle Neutron Diffractometer at HFIR | ORNL Neutron Sciences  

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

US/Japan Wide-Angle Neutron Diffractometer US/Japan Wide-Angle Neutron Diffractometer WAND Instrument scientist Jaime Fernandez-Baca (left) with a visiting researcher at WAND. The Wide-Angle Neutron Diffractometer (WAND) at the HFIR HB-2C beam tube was designed to provide two specialized data-collection capabilities: (1) fast measurements of medium-resolution powder-diffraction patterns and (2) measurements of diffuse scattering in single crystals using flat-cone geometry. For these purposes, this instrument is equipped with a curved, one-dimensional 3He position-sensitive detector covering 125º of the scattering angle with the focal distance of 71 cm. The sample and detector can be tilted in the flat-cone geometry mode. These features enable measurement of single-crystal diffraction patterns in a short time over a

95

From Powder Diffraction Data To Crystal Structure  

Science Conference Proceedings (OSTI)

... for mechanochemical mills mill movable stand Page 23. MECHANISTIC STUDIES - (a) Proper handling of the two halves of the PMMA milling jar ...

2013-06-07T23:59:59.000Z

96

Accuracy in Powder Diffraction IV Program  

Science Conference Proceedings (OSTI)

... Jacco van de Streek University of Copenhagen, Denmark ... Henning Friis Poulsen Technical University of Denmark, Denmark ...

2013-04-19T23:59:59.000Z

97

Protein Powder Diffraction and Materials Science  

Science Conference Proceedings (OSTI)

First ex-situ/in-situ measurements of strains/stresses at engineering diffractometer VULCAN at SNS FSP-Induced Plastic Deformation and Elastic Strains in...

98

Pharmaceutical Powder Diffraction: Structure Solution from ...  

Science Conference Proceedings (OSTI)

... Crystalline solids containing 2 or more building blocks (solids at rt) in stoichiometric amounts ... blocks (solids at rt) in stoichiometric amounts N O H2N ...

2013-06-10T23:59:59.000Z

99

Accuracy in Powder Diffraction IV (APD IV)  

Science Conference Proceedings (OSTI)

... Roger Durst - 3.2 Bruker AXS, USA. ... Jonathon Wright - 7.1 European Synchrotron Radiation Facility ... David L. Bish - 11.2 Indiana University, USA. ...

2013-10-20T23:59:59.000Z

100

Neutron and X-ray diffraction studies on the high temperature phase of Mn{sub 3}(VO{sub 4}){sub 2}, the new isostructural compound NaMn{sub 4}(VO{sub 4}){sub 3} and their mixed crystals Na{sub x}Mn{sub 4.5-x/2}(VO{sub 4}){sub 3} (0{<=}x{<=}1)  

SciTech Connect

This paper presents a detailed structure analysis (combined Rietveld analysis of X-ray and neutron powder diffraction data as well as quantum mechanical calculations) of the high temperature phase of Mn{sub 3}(VO{sub 4}){sub 2} (space group I4 Macron 2d). Special attention is directed to the analysis of the local coordination around Mn{sup 2+} ions or vacancies within a stella quadrangula configuration of anions. Furthermore, the new compound NaMn{sub 4}(VO{sub 4}){sub 3} is described as well as a range of mixed crystals between NaMn{sub 4}(VO{sub 4}){sub 3} and Mn{sub 3}(VO{sub 4}){sub 2} (described by the formula Na{sub x}Mn{sub 4.5-x/2}(VO{sub 4}){sub 3}, 0{<=}x{<=}1) which were synthesized by a solid state route. All compounds were shown to be isostructural to the high temperature phase Mn{sub 3}(VO{sub 4}){sub 2}. - Graphical abstract: The crystal structure of the new compound NaMn{sub 4}(VO{sub 4}){sub 3}. Highlights: Black-Right-Pointing-Pointer We present neutron and X-ray diffraction studies on high temperature-Mn{sub 3}(VO{sub 4}){sub 2}. Black-Right-Pointing-Pointer Structural details of partly filled stellae quadrangulae positions are discussed. Black-Right-Pointing-Pointer Refined structural parameters and theoretical calculations are compared. Black-Right-Pointing-Pointer We investigate the mixed crystal system Mn{sub 3}(VO{sub 4}){sub 2}-NaMn{sub 4}(VO{sub 4}){sub 3}.

Clemens, Oliver [Universitaet des Saarlandes, Institut fuer Anorganische und Analytische Chemie und Radiochemie, Am Markt, Zeile 5, 66125 Saarbruecken (Germany)] [Universitaet des Saarlandes, Institut fuer Anorganische und Analytische Chemie und Radiochemie, Am Markt, Zeile 5, 66125 Saarbruecken (Germany); Haberkorn, Robert [Universitaet des Saarlandes, Anorganische Festkoerperchemie, Am Markt, Zeile 3, 66125 Saarbruecken (Germany)] [Universitaet des Saarlandes, Anorganische Festkoerperchemie, Am Markt, Zeile 3, 66125 Saarbruecken (Germany); Springborg, Michael [Universitaet des Saarlandes, Physikalische und Theoretische Chemie, Campus B2 2, 66123 Saarbruecken (Germany)] [Universitaet des Saarlandes, Physikalische und Theoretische Chemie, Campus B2 2, 66123 Saarbruecken (Germany); Beck, Horst Philipp, E-mail: hp.beck@mx.uni-saarland.de [Universitaet des Saarlandes, Institut fuer Anorganische und Analytische Chemie und Radiochemie, Am Markt, Zeile 5, 66125 Saarbruecken (Germany)

2012-10-15T23:59:59.000Z

Note: This page contains sample records for the topic "neutron powder diffraction" 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

Diffraction Studies of Irradiated Cladding and Duct Reactor Materials  

Science Conference Proceedings (OSTI)

Symposium, Characterization of Nuclear Reactor Materials and Components with Neutron and Synchrotron Radiation. Presentation Title, Diffraction Studies of...

102

Diffraction shaders  

Science Conference Proceedings (OSTI)

Keywords: Fourier transform, Kirchoff theory, diffraction, random processes, rough surface scattering, shading models

Jos Stam

1999-07-01T23:59:59.000Z

103

Applied Neutron Scattering in Engineering and Materials Science ...  

Science Conference Proceedings (OSTI)

Neutron Diffraction Studies of Residual Stresses around Gouges and Gouged Dents in Pipelines Neutron Diffraction Study and EVPSC Modeling of the...

104

JOURNAL DE PHYSIQUE Colloque C I, supple'mentau no2-3, Tome 32, Fe'vrier-Mars1971,page C 1 -362 NEUTRON DIFFRACTION STUDY OF Ho, ,-DY,~AND Ho5,-Dy5  

E-Print Network (OSTI)

NEUTRON DIFFRACTION STUDY OF Ho, ,-DY,~AND Ho5,-Dy5 IN AN EXTERNAL MAGNETIC FIELD (*) Q. H. KHAN dans un champ magnktique. Quand le champ est parallele a l'axe a de I'alliage Ho25-Dy75a la temperature-ferromagnttique obliqueferromagni5tiqueparallele a l'axe a. La dquence correspondante trouvee pour un champ parallitle a I'axe b est

Paris-Sud XI, Université de

105

Structure and Phase Transitions of Monolayers of Intermediate-length n-alkanes on Graphite Studied by Neutron Diffraction and Molecular Dynamics Simulation  

Science Conference Proceedings (OSTI)

We present evidence from neutron diffraction measurements and molecular dynamics (MD) simulations of three different monolayer phases of the intermediate-length alkanes tetracosane (n-C(24)H(50) denoted as C24) and dotriacontane (n-C(32)H(66) denoted as C32) adsorbed on a graphite basal-plane surface. Our measurements indicate that the two monolayer films differ principally in the transition temperatures between phases. At the lowest temperatures, both C24 and C32 form a crystalline monolayer phase with a rectangular-centered (RC) structure. The two sublattices of the RC structure each consists of parallel rows of molecules in their all-trans conformation aligned with their long axis parallel to the surface and forming so-called lamellas of width approximately equal to the all-trans length of the molecule. The RC structure is uniaxially commensurate with the graphite surface in its [110] direction such that the distance between molecular rows in a lamella is 4.26 A=sqrt[3a(g)], where a(g)=2.46 A is the lattice constant of the graphite basal plane. Molecules in adjacent rows of a lamella alternate in orientation between the carbon skeletal plane being parallel and perpendicular to the graphite surface. Upon heating, the crystalline monolayers transform to a 'smectic' phase in which the inter-row spacing within a lamella expands by approximately 10% and the molecules are predominantly oriented with the carbon skeletal plane parallel to the graphite surface. In the smectic phase, the MD simulations show evidence of broadening of the lamella boundaries as a result of molecules diffusing parallel to their long axis. At still higher temperatures, they indicate that the introduction of gauche defects into the alkane chains drives a melting transition to a monolayer fluid phase as reported previously.

Taub, H. [University of Missouri, Columbia; Hansen, F.Y. [Technical University of Denmark; Diama, Amand [National University of the Ivory Coast; Matthies, Blake [Goodyear Tire and Rubber Company, The; Criswell, Leah [University of Missouri, Columbia; Mo, Haiding [Advanced Optowave Corporation; Bai, M [University of Missouri, Columbia; Herwig, Kenneth W [ORNL

2009-01-01T23:59:59.000Z

106

Phonon Studies with Inelastic Neutron Scattering and First ...  

Science Conference Proceedings (OSTI)

Presentation Title, Phonon Studies with Inelastic Neutron Scattering and .... by Asynchronous In-Situ Neutron Diffraction at the Spallation Neutron Source.

107

Teacher Programs | ORNL Neutron Sciences  

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

Diffractometer, explains neutron diffractometry to teachers participating in the STARs program. Ashfia Huq (front), instrument scientist for the SNS Powder Diffractometer, explains...

108

Diffractive processes  

SciTech Connect

Recent results on elastic scattering of hadrons, single and double inelastic diffraction, and double Pomeron exchange are reviewed. Comments are made on features of the data that can be simply understood using optical models or the triple Regge model. (auth)

Derrick, M.

1975-01-01T23:59:59.000Z

109

Energetic powder  

DOE Patents (OSTI)

Fluoroalkylsilane-coated metal particles. The particles have a central metal core, a buffer layer surrounding the core, and a fluoroalkylsilane layer attached to the buffer layer. The particles may be prepared by combining a chemically reactive fluoroalkylsilane compound with an oxide coated metal particle having a hydroxylated surface. The resulting fluoroalkylsilane layer that coats the particles provides them with excellent resistance to aging. The particles can be blended with oxidant particles to form energetic powder that releases chemical energy when the buffer layer is physically disrupted so that the reductant metal core can react with the oxidant.

Jorgensen, Betty S. (Jemez Springs, NM); Danen, Wayne C. (Los Alamos, NM)

2003-12-23T23:59:59.000Z

110

Two-Dimensional X-ray Diffraction for Advanced Materials Analysis  

Science Conference Proceedings (OSTI)

Deformation Of Shape Memory Alloys Under Biaxial Loading .... Software Tools for the Monitoring, Analysis and Interpretation of Engineering Neutron Diffraction

111

Advances in 3D Micro-Diffraction with Small Beams.  

Science Conference Proceedings (OSTI)

In-Situ Neutron Diffraction and Crystal Plasticity Modeling of a-Uranium In-Situ Studies of the ... Thermal Residual Stresses and Strains in Depleted Uranium.

112

FABRICATION OF NEUTRON SOURCES  

DOE Patents (OSTI)

A method is presented for preparing a more efficient neutron source comprising inserting in a container a quantity of Po-210, inserting B powder coated with either Ag, Pt, or Ni. The container is sealed and then slowly heated to about 450 C to volatilize the Po and effect combination of the coated powder with the Po. The neutron flux emitted by the unit is moritored and the heating step is terminated when the flux reaches a maximum or selected level.

Birden, J.H.

1959-01-20T23:59:59.000Z

113

Direct evidence of a zigzag spin-chain structure in the honeycomb lattice: A neutron and x-ray diffraction investigation of single-crystal Na2IrO3  

Science Conference Proceedings (OSTI)

We have combined single crystal neutron and x-ray diffractions to investigate the magnetic and crystal structures of the honeycomb lattice $\\rm Na_2IrO_3$. The system orders magnetically below $18.1(2)$~K with Ir$^{4+}$ ions forming zigzag spin chains within the layered honeycomb network with ordered moment of $\\rm 0.22(1)~\\mu_B$/Ir site. Such a configuration sharply contrasts the N{\\'{e}}el or stripe states proposed in the Kitaev-Heisenberg model. The structure refinement reveals that the Ir atoms form nearly ideal 2D honeycomb lattice while the $\\rm IrO_6$ octahedra experience a trigonal distortion that is critical to the ground state. The results of this study provide much-needed experimental insights into the magnetic and crystal structure crucial to the understanding of the exotic magnetic order and possible topological characteristics in the 5$d$-electron based honeycomb lattice.

Ye, Feng [ORNL; Chi, Songxue [ORNL; Cao, Huibo [ORNL; Chakoumakos, Bryan C [ORNL; Fernandez-Baca, Jaime A [ORNL; Custelcean, Radu [ORNL; Qi, Tongfei [University of Kentucky; Korneta, O. B. [University of Kentucky, Lexington; Cao, Gang [University of Kentucky

2012-01-01T23:59:59.000Z

114

Science | ORNL Neutron Sciences  

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

Neutron Science Neutron Science Neutron Scattering Science Neutrons are one of the fundamental particles that make up matter and have properties that make them ideal for certain types of research. In the universe, neutrons are abundant, making up more than half of all visible matter. Neutron scattering provides information about the positions, motions, and magnetic properties of solids. When a beam of neutrons is aimed at a sample, many neutrons will pass through the material. But some will interact directly with atomic nuclei and "bounce" away at an angle, like colliding balls in a game of pool. This behavior is called neutron diffraction, or neutron scattering. Using detectors, scientists can count scattered neutrons, measure their energies and the angles at which they scatter, and map their final position

115

Neutron scattering characterization of pure and rare-earth modified zirconia catalysis.  

SciTech Connect

The combined application of neutron powder diffraction, small angle neutron scattering and neutron inelastic scattering has led to improved understanding of the crystal phases, defect structure, microstructure and hydroxyl/water dynamics in pure and lanthanide-modified zirconia catalysts. Powder diffraction experiments quantified the degree of stabilization and provided evidence for static, oxygen vacancy-induced atomic displacements in stabilized zirconia. Quantitative assessment of Bragg peak breadths led to measurements of ''grain size'', representing coherency length of long-range ordered atomic arrangements (crystals). Small angle neutron scattering provided a separate measurement of ''grain size'', representing the average size of the primary particles in the aggregates, and the evolution of porosity (micro- versus meso-) and surface roughness caused by RE modification and heat treatment. Finally, the dynamics of hydrogen atoms associated with surface hydroxyls and adsorbed water was investigated by neutron-inelastic scattering, revealing changes in frequency and band breadth of O-H stretch, H-O-H bend, and librational motion of water molecules.

Loong, C.-K.; Ozawa, M.; Richardson, J. W., Jr.; Suzuki, S.; Thiyagarajan, P.

1997-11-18T23:59:59.000Z

116

Powder treatment process  

SciTech Connect

(1) A process comprising spray drying a powder-containing slurry, the slurry containing a powder constituent susceptible of oxidizing under the temperature conditions of the spray drying, while reducing the tendency for oxidation of the constituent by including as a liquid constituent of the slurry an organic liquid; (2) a process comprising spray drying a powder-containing slurry, the powder having been pretreated to reduce content of a powder constituent susceptible of oxidizing under the temperature conditions of the spray drying, the pretreating comprising heating the powder to react the constituent; and (3) a process comprising reacting ceramic powder, grinding the reacted powder, slurrying the ground powder, spray drying the slurried powder, and blending the dried powder with metal powder.

Weyand, John D. (Greensburg, PA)

1988-01-01T23:59:59.000Z

117

Powder treatment process  

DOE Patents (OSTI)

Disclosed are: (1) a process comprising spray drying a powder-containing slurry, the slurry containing a powder constituent susceptible of oxidizing under the temperature conditions of the spray drying, while reducing the tendency for oxidation of the constituent by including as a liquid constituent of the slurry an organic liquid; (2) a process comprising spray drying a powder-containing slurry, the powder having been pretreated to reduce content of a powder constituent susceptible of oxidizing under the temperature conditions of the spray drying, the pretreating comprising heating the powder to react the constituent; and (3) a process comprising reacting ceramic powder, grinding the reacted powder, slurrying the ground powder, spray drying the slurried powder, and blending the dried powder with metal powder. 2 figs.

Weyand, J.D.

1988-02-09T23:59:59.000Z

118

Diffraction Shaders  

E-Print Network (OSTI)

The reflection of light from surfaces is a fundamental problem in computer graphics. Although many reflection models have been proposed, few take into account the wave nature of light. In this paper, we derive a new class of reflection models for metallic surfaces that handle the effects of diffraction. Diffraction is a purely wave-like phenomenon and cannot be properly modeled using the ray theory of light alone. A common example of a surface which exhibits diffraction is the compact disk. A characteristic of such surfaces is that they reflect light in a very colorful manner. Our model is also a generalization of most reflection models encountered in computer graphics. In particular, we extend the He-Torrance model to handle anisotropic reflections. This is achieved by rederiving, in a more general setting, results from surface wave physics which were taken for granted by other researchers. Specifically, our use of Fourier analysis has enabled us to tackle the difficult task of analytically computing the Kirchhoff integral of surface scattering.

Jos Stam

1999-01-01T23:59:59.000Z

119

Research Highlights | ORNL Neutron Sciences  

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

Research Highlights For all the latest highlights on research at HFIR and SNS, please see the links at left. Featured Research Neutron diffraction reveals semiconducting phase and...

120

Powder dispersion system  

SciTech Connect

A powder dispersion method and apparatus comprising an air eductor and a powder dispensing syringe inserted into a suction connection of the air eductor.

Gorenz, Heather M. (Albuquerque, NM); Brockmann, John E. (Albuquerque, NM); Lucero, Daniel A. (Albuquerque, NM)

2011-09-20T23:59:59.000Z

Note: This page contains sample records for the topic "neutron powder diffraction" 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

Dissimilar Metal Weld Residual Stress Mappings by Neutron and X ...  

Science Conference Proceedings (OSTI)

... (IHD), X-ray diffraction (XRD) and neutron diffraction (ND) methods conducted by Oak Ridge National Laboratory (ORNL). ... Planned: A CD-only volume...

122

Industrial Applications at Small Angle Neutron Scattering and ...  

Science Conference Proceedings (OSTI)

... at Small Angle Neutron Scattering and Neutron Diffraction of HANARO Reactor .... Structure/Microstructure Analysis of Faulted and Modular Materials from...

123

FABRICATION OF NEUTRON SOURCES  

DOE Patents (OSTI)

A method is presented for preparing a neutron source from polonium-210 and substances, such as beryllium and boron, characterized by emission of neutrons upon exposure to alpha particles from the polonium. According to the invention, a source is prepared by placing powdered beryllium and a platinum foil electroplated with polonium-2;.0 in a beryllium container. The container is sealed and then heated by induction to a temperature of 450 to 1100 deg C to volatilize the polonium off the foil into the powder. The heating step is terminated upon detection of a maximum in the neutron flux level.

Birden, J.H.

1959-04-21T23:59:59.000Z

124

Local Structure from Diffraction  

Science Conference Proceedings (OSTI)

Mar 14, 2012 ... Neutron and X-Ray Studies of Advanced Materials V: Centennial: Local .... we use both the high-flux neutrons at the Spallation Neutron Source...

125

Preparation and structural study from neutron diffraction data of Pr{sub 5}Mo{sub 3}O{sub 16}  

SciTech Connect

The title compound has been prepared as polycrystalline powder by thermal treatments of mixtures of Pr{sub 6}O{sub 11} and MoO{sub 2} in air. In the literature, an oxide with a composition Pr{sub 2}MoO{sub 6} has been formerly described to present interesting catalytic properties, but its true stoichiometry and crystal structure are reported here for the first time. It is cubic, isostructural with CdTm{sub 4}Mo{sub 3}O{sub 16} (space group Pn-3n, Z=8), with a=11.0897(1) A. The structure contains MoO{sub 4} tetrahedral units, with Mo-O distances of 1.788(2) A, fully long-range ordered with PrO{sub 8} polyhedra; in fact it can be considered as a superstructure of fluorite (M{sub 8}O{sub 16}), containing 32 MO{sub 2} fluorite formulae per unit cell, with a lattice parameter related to that of cubic fluorite (a{sub f}=5.5 A) as a{approx}2a{sub f}. A bond valence study indicates that Mo exhibits a mixed oxidation state between 5+ and 6+ (perhaps accounting for the excellent catalytic properties). One kind of Pr atoms is trivalent whereas the second presents a mixed Pr{sup 3+}-Pr{sup 4+} oxidation state. The similarity of the XRD pattern with that published for Ce{sub 2}MoO{sub 6} suggests that this compound also belongs to the same structural type, with an actual stoichiometry Ce{sub 5}Mo{sub 3}O{sub 16}. -- Graphical Abstract: Formerly formulated as Pr{sub 2}MoO{sub 6}, the title compound is a cubic superstructure of fluorite (a=11.0897(1) A, space group Pn-3n) due to the long-range ordering of PrO{sub 8} scalenohedra and MoO{sub 4} tetrahedral units, showing noticeable shifts of the oxygen positions in order to provide a tetrahedral coordination for Mo ions. A mixed valence Mo{sup 5+}-Mo{sup 6+} is identified, which could account for the excellent catalytic properties of this material. Display Omitted

Martinez-Lope, M.J. [Instituto de Ciencia de Materiales de Madrid, C.S.I.C., Cantoblanco, E-28049 Madrid, Spain. (Spain); Alonso, J.A., E-mail: ja.alonso@icmm.csic.e [Instituto de Ciencia de Materiales de Madrid, C.S.I.C., Cantoblanco, E-28049 Madrid, Spain. (Spain); Sheptyakov, D.; Pomjakushin, V. [Laboratory for Neutron Scattering, Paul Scherrer Institut, CH-5232 Villigen PSI (Switzerland)

2010-12-15T23:59:59.000Z

126

Awards 2010 | ORNL Neutron Sciences  

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

lead instrument scientist for VULCAN, a state-of-the-art engineering diffractometer at SNS. Wang also serves as group leader for the Powder Diffraction Instrument Group. Wang was...

127

Precision powder feeder  

DOE Patents (OSTI)

A new class of precision powder feeders is disclosed. These feeders provide a precision flow of a wide range of powdered materials, while remaining robust against jamming or damage. These feeders can be precisely controlled by feedback mechanisms.

Schlienger, M. Eric (Albuquerque, NM); Schmale, David T. (Albuquerque, NM); Oliver, Michael S. (Sandia Park, NM)

2001-07-10T23:59:59.000Z

128

Powder Materials Committee  

Science Conference Proceedings (OSTI)

Powder Materials for Energy Efficiency in Transportation; January 2011: Organized By: Fernand Marquis Nanomaterials for Renewable Energy...

129

Definition: X-Ray Diffraction (XRD) | Open Energy Information  

Open Energy Info (EERE)

X-Ray Diffraction (XRD) X-Ray Diffraction (XRD) Jump to: navigation, search Dictionary.png X-Ray Diffraction (XRD) X-Ray Diffraction (XRD) is a laboratory-based technique commonly used for identification of crystalline materials and analysis of unit cell dimensions. One of two primary types of XRD analysis (X-ray powder diffraction and single-crystal XRD) is commonly applied to samples to obtain specific information about the crystalline material under investigation. X-ray powder diffraction is widely used in geology, environmental science, material science, and engineering to rapidly identify unknown crystalline substances (typically in less than 20 minutes). A pure, finely ground, and homogenized sample is required for determination of the bulk composition. Additional uses include detailed

130

Powder Diffractometer (POWGEN) - ORNL Neutron Sciences  

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

Research Highlights Theory meets experiment: structure-property relationships in an electrode material for solid-oxide fuel cells Possible valence bond condensation in a frustrated...

131

Dr. Ashfia Huq | ORNL Neutron Sciences  

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

Ashfia Huq Ashfia Huq Dr. Ashfia Huq Instrument Scientist: POWGEN Education PhD in Physics, Stony Brook University, in Stony Brook, New York (May 2003) AB degree, Magna Cum Laude with majors in Physics and Computer Science, Mount Holyoke College, South Hadley, Massachusetts (May 1996) Description of Research My primary research interest is neutron and X-ray powder diffraction of condensed matter systems and materials for energy storage. Topics include battery materials, solid oxide fuel cell (SOFC) materials, hydrogen storage materials, catalysis, and magnetic and structural properties of strongly correlated electron systems such as geometrically frustrated magnets, superconductors, etc. Selected Publications Zhonghe Bi, Juan Pena-Martinez, Jung-Hyun Kim, Craig A. Bridges, Ashfia

132

Using Neutrons to Study Radioactive Materials  

Science Conference Proceedings (OSTI)

Symposium, Applied Neutron Scattering in Engineering and Materials Science Research ... to the unique infrastructure and specialized staff of the Nuclear Laboratory. Shielded cells enable neutron diffraction studies on highly radioactive...

133

Investigating Microscopic Heat Transport with Neutron Scattering  

Science Conference Proceedings (OSTI)

In-Situ Neutron Diffraction and Crystal Plasticity Modeling of a-Uranium In-Situ Studies of the ... Thermal Residual Stresses and Strains in Depleted Uranium.

134

Quantum Condensed Matter Division | Neutron Science | ORNL  

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

instruments used for diffraction and inelastic neutron scattering at both SNS and HFIR. The science conducted by our staff members emphasizes materials with emergent...

135

Accuracy in Powder Diffraction IV NIST, Gaithersburg MD ...  

Science Conference Proceedings (OSTI)

... iron) Steel Slag Page 5. Iron making - value chain Raw materials Coal Lumpy ore Mining Waste Slag Final product Steel (Retained Austenite) ...

2013-06-07T23:59:59.000Z

136

Powder diffraction: the best is yet to come , but  

Science Conference Proceedings (OSTI)

... superhard graphite pharmaceuticals turbine blade tensile stress pencil lead proteins paracetamol nanomaterials gas storage CO2 sequestration ...

2013-06-07T23:59:59.000Z

137

Accuracy In Powder Diffraction: Are We There Yet ?  

Science Conference Proceedings (OSTI)

... imaging plates, CCD cameras, CMOS cameras, gas detectors, semiconductor ... in X-ray instrument alignment procedures in lean manufacturing. ...

2013-04-19T23:59:59.000Z

138

Multiple feed powder splitter  

DOE Patents (OSTI)

A device for providing uniform powder flow to the nozzles when creating solid structures using a solid fabrication system such as the directed light fabrication (DLF) process. In the DLF process, gas entrained powders are passed through the focal point of a moving high-power laser light which fuses the particles in the powder to a surface being built up in layers. The invention is a device providing uniform flow of gas entrained powders to the nozzles of the DLF system. The device comprises a series of modular splitters which are slidably interconnected and contain an integral flow control mechanism. The device can take the gas entrained powder from between one to four hoppers and split the flow into eight tubular lines which feed the powder delivery nozzles of the DLF system.

Lewis, Gary K. (Los Alamos, NM); Less, Richard M. (Los Alamos, NM)

2002-01-01T23:59:59.000Z

139

Multiple feed powder splitter  

DOE Patents (OSTI)

A device for providing uniform powder flow to the nozzles when creating solid structures using a solid fabrication system such as the directed light fabrication (DLF) process. In the DLF process, gas entrained powders are passed through the focal point of a moving high-power laser light which fuses the particles in the powder to a surface being built up in layers. The invention is a device providing uniform flow of gas entrained powders to the nozzles of the DLF system. The device comprises a series of modular splitters which are slidably interconnected and contain an integral flow control mechanism. The device can take the gas entrained powder from between one to four hoppers and split the flow into eight tubular lines which feed the powder delivery nozzles of the DLF system.

Lewis, Gary K. (Los Alamos, NM); Less, Richard M. (Los Alamos, NM)

2001-01-01T23:59:59.000Z

140

Fundamentals of Neutron Diffraction NCNR Summer School ...  

Science Conference Proceedings (OSTI)

... Page 35. 1 M 2 M Transfer Matrix 1 2 MMM = 1 M 2 M 3 M 1 2 3 M MMM = :historically, also is called the "optical" matrix. M Aside Page 36. j M ...

2006-08-09T23:59:59.000Z

Note: This page contains sample records for the topic "neutron powder diffraction" 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

Neutron Diffraction And Finite Element Simulations.  

Science Conference Proceedings (OSTI)

For example, this was done by Bucezek at al. [18] on a cylinder made of brass. As the materials are different, their results cannot be applied for the present study,...

142

X-Ray and Neutron Diffraction  

Science Conference Proceedings (OSTI)

Oct 20, 2010 ... Advanced X-Ray Scattering Techniques for Multi-Length Scale ... ?-Ti using the 3DXRD station 34-ID-E at the Advanced Photon Source, Argonne National Laboratory. ... Research at APS 34-ID-E, partly funded by BES/DOE.

143

X-Ray and Neutron Diffraction  

Science Conference Proceedings (OSTI)

Oct 27, 2009 ... Use of the Advanced Photon Source at Argonne National Laboratory was supported by the U. S. Department of Energy, Office of Science, Office...

144

Development of Lithium Lanthanide Borate Scintillator for Neutron Scattering Applications  

Science Conference Proceedings (OSTI)

We have completed the design and testing of neutron scattering instrument detectors for powder diffractometers and single crystal diffractometers. These detectors meet the performance requirements for these types of instruments at the Department of Energy Spallation Neutron Source facility.

Czirr, J.B.; McKnight, T.; Merrill, D.

2004-09-20T23:59:59.000Z

145

Powder Metallurgy Bearing Failure  

Science Conference Proceedings (OSTI)

The bearings were oil impregnated, porous, powder metallurgy bushings. Even after the fire, lubricant ... Failure Analysis of Four Graphite Pump Seal Faces.

146

Supercool Neutrons (Ultracold Neutrons)  

E-Print Network (OSTI)

in the USA. Why neutrons? Neutrons possess physical properties that make them valuable investigative tools Spallation Neutron Source (SNS) The world's most intense pulsed accelerator-based neutron source. High Flux Isotope Reactor (HFIR) The highest flux reactor-based neutron source for condensed matter research

Martin, Jeff

147

Study of bound hydrogen in powders of diamond nanoparticles  

Science Conference Proceedings (OSTI)

In order to access feasibility of increasing albedo of very cold neutrons from powder of diamond nanoparticles, we studied hydrogen bound to surface of diamond nanoparticles, which causes unwanted losses of neutrons. We showed that one could decrease a fraction of hydrogen atoms from a ratio C{sub 7.4{+-}0.15}H to a ratio C{sub 12.4{+-}0.2}H by means of thermal treatment and outgasing of powder. Measurements of atomic excitation spectra of these samples, using a method of inelastic incoherent neutron scattering, indicate that residual hydrogen is chemically bound to carbon, while a removed fraction was composed of adsorbed water. The total cross section of scattering of neutrons with a wavelength of 4.4 Angstrom-Sign on residual hydrogen atoms equals 108 {+-} 2 b; it weakly changes with temperature. Thus preliminary cleaning of powder from hydrogen and its moderate cooling do not improve considerably neutron albedo from powder of nano-diamonds. An alternative approach is isotopic replacement of hydrogen by deuterium.

Krylov, A. R.; Lychagin, E. V.; Muzychka, A. Yu. [Joint Institute for Nuclear Research (Russian Federation); Nesvizhevsky, V. V., E-mail: nesvizhevsky@ill.eu [Institut Laue-Langevin (Russian Federation); Nekhaev, G. V.; Strelkov, A. V. [Joint Institute for Nuclear Research (Russian Federation); Ivanov, A. S. [Institut Laue-Langevin (Russian Federation)

2011-12-15T23:59:59.000Z

148

Wavelength-Shifting-Fiber Scintillation Detectors for Thermal Neutron Imaging at SNS  

Science Conference Proceedings (OSTI)

We have developed wavelength-Shifting-fiber Scintillator Detector (SSD) with 0.3 m2 area per module. Each module has 154 x 7 pixels and a 5 mm x 50 mm pixel size. Our goal is to design a large area neutron detector offering higher detection efficiency and higher count-rate capability for Time-Of-Flight (TOF) neutron diffraction in Spallation Neutron Source (SNS). A ZnS/6LiF scintillator combined with a novel fiber encoding scheme was used to record the neutron events. A channel read-out-card (CROC) based digital-signal processing electronics and position-determination algorithm was applied for neutron imaging. Neutron-gamma discrimination was carried out using pulse-shape discrimination (PSD). A sandwich flat-scintillator detector can have detection efficiency close to He-3 tubes (about 10 atm). A single layer flat-scintillator detector has count rate capability of 6,500 cps/cm2, which is acceptable for powder diffractometers at SNS.

Clonts, Lloyd G [ORNL; Cooper, Ronald G [ORNL; Crow, Lowell [ORNL; Diawara, Yacouba [ORNL; Ellis, E Darren [ORNL; Funk, Loren L [ORNL; Hannan, Bruce W [ORNL; Hodges, Jason P [ORNL; Richards, John D [ORNL; Riedel, Richard A [ORNL; Wang, Cai-Lin [ORNL

2012-01-01T23:59:59.000Z

149

Coating Surfaces with Superhydrophobic Powder  

powder spraying process, dry resin powder is sprayed on to a given substrate. The ... Other fluid dynamic and heat transfer applications Patent

150

Electron Backscatter Diffraction  

Science Conference Proceedings (OSTI)

Oct 19, 2011 ... Recent Advances in Structural Characterization of Materials: Electron Backscatter Diffraction Sponsored by: MS&T Organization Program...

151

Powder and Composite Materials  

Science Conference Proceedings (OSTI)

Aug 8, 2013... Yonsei University; Robert O'Donnell, CSIRO; Jie Liu, Duke University .... At the capture of neutron in wide energy spectrum, the (n, ?) reaction...

152

Neutron proton crystallography station (PCS)  

SciTech Connect

The PCS (Protein Crystallography Station) at Los Alamos Neutron Science Center (LANSCE) is a unique facility in the USA that is designed and optimized for detecting and collecting neutron diffraction data from macromolecular crystals. PCS utilizes the 20 Hz spallation neutron source at LANSCE to enable time-of-flight measurements using 0.6-7.0 {angstrom} neutrons. This increases the neutron flux on the sample by using a wavelength range that is optimal for studying macromolecular crystal structures. The diagram below show a schematic of PCS and photos of the detector and instrument cave.

Fisher, Zoe [Los Alamos National Laboratory; Kovalevsky, Andrey [Los Alamos National Laboratory; Johnson, Hannah [Los Alamos National Laboratory; Mustyakimov, Marat [Los Alamos National Laboratory

2009-01-01T23:59:59.000Z

153

Neutron Scattering Studies of Fundamental Processes in Earth Materials, Final Report  

DOE Green Energy (OSTI)

The aim of this work was to use neutron scattering techniques to explore the dynamics and structure of water in rock samples. The dynamics of water in rock at low (residual) saturation are directly related to the transport properties of fluids within the host rock. The structure of water in rock may be related to the elastic behavior of the rock, which in many cases is nonlinear and hysteretic. Neutron scattering techniques allow us to study water in intact rock samples at both the molecular and microstructural scales. Our samples were Berea sandstone, Calico Hills and Prow Pass tuffs from Yucca Mountain, NV, and pure samples of the tuff constituents, specifically mordenite and clinoptilolite. We chose Berea sandstone because its macroscopic elastic behavior is known to be highly unusual, and the microscopic mechanisms producing this behavior are not understood. We chose Yucca Mountain tuff, because the fluid transport properties of the geologic structure at Yucca Mountain, Nevada could be relevant to the performance of a high level nuclear waste repository at that site. Neutron scattering methods have a number of properties that are extremely useful for the study of earth materials. In contrast to X-rays, neutrons have very low absorption cross-sections for most elements so that entire bulk samples of considerable size can be 'illuminated' by the neutron beam. Similarly, samples that are optically opaque can be readily investigated by inelastic neutron scattering techniques. Neutrons are equally sensitive to light atoms as to heavy atoms, and can, for example, readily distinguish between Al and Si, neighboring atoms in the periodic table that are difficult to tell apart by X-ray diffraction. Finally, neutrons are particularly sensitive to hydrogen and thus can be used to study the motions, both vibrational and diffusive, of H-containing molecules in rocks, most notably of course, water. Our studies were primarily studies of guest molecules (in our case, water) in a host material (rock). We used three neutron scattering techniques: quasielastic neutron scattering (QNS), inelastic neutron scattering (INS), and neutron powder diffraction (NPD). We used QNS to measure the translational and rotational diffusional motion of water in rock; INS vibrational spectra allowed us to determine the nature of residual water in a sample (disassociated, chemisorbed, or physisorbed); and NPD measurements may allow us to determine the locations of residual water molecules (and the associated dynamic disorder), and thereby understand the binding of water molecules in our samples.

McCall, K. R.

2007-06-11T23:59:59.000Z

154

X-Ray Diffraction (XRD) | Open Energy Information  

Open Energy Info (EERE)

X-Ray Diffraction (XRD) X-Ray Diffraction (XRD) Jump to: navigation, search GEOTHERMAL ENERGYGeothermal Home Exploration Technique: X-Ray Diffraction (XRD) Details Activities (0) Areas (0) Regions (0) NEPA(0) Exploration Technique Information Exploration Group: Lab Analysis Techniques Exploration Sub Group: Rock Lab Analysis Parent Exploration Technique: Rock Lab Analysis Information Provided by Technique Lithology: Rapid and unambiguous identification of unknown minerals.[1] Stratigraphic/Structural: Hydrological: Thermal: Dictionary.png X-Ray Diffraction (XRD): X-Ray Diffraction (XRD) is a laboratory-based technique commonly used for identification of crystalline materials and analysis of unit cell dimensions. One of two primary types of XRD analysis (X-ray powder diffraction and single-crystal XRD) is commonly applied to samples to

155

Portable X-Ray Diffraction (XRD) | Open Energy Information  

Open Energy Info (EERE)

Portable X-Ray Diffraction (XRD) Portable X-Ray Diffraction (XRD) Jump to: navigation, search GEOTHERMAL ENERGYGeothermal Home Exploration Technique: Portable X-Ray Diffraction (XRD) Details Activities (0) Areas (0) Regions (0) NEPA(0) Exploration Technique Information Exploration Group: Field Techniques Exploration Sub Group: Data Collection and Mapping Parent Exploration Technique: Data Collection and Mapping Information Provided by Technique Lithology: Rapid and unambiguous identification of unknown minerals.[1] Stratigraphic/Structural: Hydrological: Thermal: Dictionary.png Portable X-Ray Diffraction (XRD): Portable X-Ray Diffraction (XRD) is a field-based technique that can be used for identification of crystalline materials and analysis of unit cell dimensions. Portable XRD analysis is similar to X-ray powder diffraction,

156

2011 U.S. National School on Neutron and X-ray Scattering  

Science Conference Proceedings (OSTI)

The 13th annual U.S. National School on Neutron and X-ray Scattering was held June 11 to 25, 2011, at both Oak Ridge and Argonne National Laboratories. This school brought together 65 early career graduate students from 56 different universities in the US and provided them with a broad introduction to the techniques available at the major large-scale neutron and synchrotron x-ray facilities. This school is focused primarily on techniques relevant to the physical sciences, but also touches on cross-disciplinary bio-related scattering measurements. During the school, students received lectures by over 30 researchers from academia, industry, and national laboratories and participated in a number of short demonstration experiments at Argonne's Advanced Photon Source (APS) and Oak Ridge's Spallation neutron Source (SNS) and High Flux Isotope Reactor (HFIR) facilities to get hands-on experience in using neutron and synchrotron sources. The first week of this year's school was held at Oak Ridge National Lab, where Lab director Thom Mason welcomed the students and provided a shitorical perspective of the neutron and x-ray facilities both at Oak Ridge and Argonne. The first few days of the school were dedicated to lectures laying out the basics of scattering theory and the differences and complementarity between the neutron and x-ray probes given by Sunil Sinha. Jack Carpenter provided an introduction into how neutrons are generated and detected. After this basic introduction, the students received lectures each morning on specific techniques and conducted demonstration experiments each afternoon on one of 15 different instruments at either the SNS or HFIR. Some of the topics covered during this week of the school included inelastic neutron scattering by Bruce Gaulin, x-ray and neutron reflectivity by Chuck Majkrazak, small-angle scattering by Volker Urban, powder diffraction by Ashfia Huq and diffuse scattering by Gene Ice.

Lang, Jonathan [Argonne National Laboratory (ANL); te Vethuis, Suzanne [Argonne National Laboratory (ANL); Ekkebus, Allen E [ORNL; Chakoumakos, Bryan C [ORNL; Budai, John D [ORNL

2012-01-01T23:59:59.000Z

157

Electron Beam Powder Bed Processes  

Science Conference Proceedings (OSTI)

Advanced Materials, Processes and Applications for Additive Manufacturing : Electron Beam Powder Bed Processes Program Organizers: Andrzej...

158

A Comparison of Cocrystal Structure Solutions from Powder and Single Crystal Techniques  

DOE Green Energy (OSTI)

We demonstrate the effectiveness and accuracy of high resolution powder diffraction for determination of cocrystal structures through a double-blind study. Structures of 10 cocrystals of varying complexity were determined independently using single crystal and powder techniques. The two methodologies give identical molecular packing and hydrogen bond topology, and an rms difference in covalent bond lengths of 0.035 {angstrom}. Powder techniques are clearly sufficient to establish a complete characterization of cocrystal geometry.

S Lapidus; P Stephens; K Arora; T Shattock; M Zaworotko

2011-12-31T23:59:59.000Z

159

Single-crystal X-ray and neutron diffraction investigations of the temperature dependence of the structure of the Tc = 10 K organic superconductor. kappa. -(ET) sub 2 Cu(NCS) sub 2. [where ET or BEDT-TTF = bis(ethylenedithio)tetrathiafulvalene, C sub 10 H sub 8 S sub 8  

Science Conference Proceedings (OSTI)

The crystal structure of {kappa}-(ET){sub 2}Cu(NCS){sub 2} (ET or BEDT-TTF = bis(ethylenedithio)tetrathiafulvalene, C{sub 10}H{sub 8}S{sub 8}) has been examined by single-crystal neutron and X-ray diffraction at temperatures between 298 and 15 K. Comparison of the low temperature ordered structures determined by use of X-ray and neutron diffraction with the previously reported crystallographically disordered room temperature X-ray structure indicates the avoidance of close H{center dot}{center dot}{center dot}H contacts as the reason for the conformational disorder of the terminal ethylene groups of the ET molecules at high temperatures. The space group is monoclinic noncentrosymmetric P2{sub 1}, Z = 2. Unit cell parameters at 118 K are a = 16.359(4), b = 8.418(2), c = 12.855(3) {angstrom}, {beta} = 111.21(2){degree}, and V = 1650.3(7) {angstrom}{sup 3}; at 15 K, a = 16.373(5), b = 8.375(3), c = 12.775(6) {angstrom}, {beta} = 111.45(4){degree}, and V = 1630(1) {angstrom}{sup 3}. The interlayer spacing a {center dot} sin {beta} remains constant upon cooling from 298 to 15 K even though the a axis increases slightly in length.

Schultz, A.J.; Beno, M.A.; Geiser, U.; Wang, H.H.; Kini, A.; Williams, J.M. (Argonne National Lab., IL (United States)); Myunghwan Whangbo (North Carolina State Univ., Raleigh (United States))

1991-10-01T23:59:59.000Z

160

Ultrafine hydrogen storage powders  

DOE Patents (OSTI)

A method of making hydrogen storage powder resistant to fracture in service involves forming a melt having the appropriate composition for the hydrogen storage material, such, for example, LaNi.sub.5 and other AB.sub.5 type materials and AB.sub.5+x materials, where x is from about -2.5 to about +2.5, including x=0, and the melt is gas atomized under conditions of melt temperature and atomizing gas pressure to form generally spherical powder particles. The hydrogen storage powder exhibits improved chemcial homogeneity as a result of rapid solidfication from the melt and small particle size that is more resistant to microcracking during hydrogen absorption/desorption cycling. A hydrogen storage component, such as an electrode for a battery or electrochemical fuel cell, made from the gas atomized hydrogen storage material is resistant to hydrogen degradation upon hydrogen absorption/desorption that occurs for example, during charging/discharging of a battery. Such hydrogen storage components can be made by consolidating and optionally sintering the gas atomized hydrogen storage powder or alternately by shaping the gas atomized powder and a suitable binder to a desired configuration in a mold or die.

Anderson, Iver E. (Ames, IA); Ellis, Timothy W. (Doylestown, PA); Pecharsky, Vitalij K. (Ames, IA); Ting, Jason (Ames, IA); Terpstra, Robert (Ames, IA); Bowman, Robert C. (La Mesa, CA); Witham, Charles K. (Pasadena, CA); Fultz, Brent T. (Pasadena, CA); Bugga, Ratnakumar V. (Arcadia, CA)

2000-06-13T23:59:59.000Z

Note: This page contains sample records for the topic "neutron powder diffraction" 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
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161

Publications from Research Conducted at WAND | ORNL Neutron Sciences  

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

Publications from Research Conducted at WAND Publications from Research Conducted at WAND 2013 Publications Durand A. M., Belanger D. P., Booth C. H., Ye F., Chi S., Fernandez-Baca J. A., Bhat M., "Magnetism and phase transitions in LaCoO3", Journal of Physics: Condensed Matter 25, 382203 (2013). Kobayashi R., Kaneko K., Wakimoto S., Chi S., Sanada N., Watanuki R., Suzuki K., "Powder neutron diffraction study of HoCoGa", Journal of the Korean Physical Society 63, 337-340 (2013). Retuerto M., Li M. R., Ignatov A., Croft M., Ramanujachary K. V., Chi S., Hodges J. P., Dachraoui W., Hadermann J., Tran T. T., Halasyamani P. S., Grams C. P., Hemberger J., Greenblatt M., "Polar and magnetic layered A-site and rock salt B-site-ordered NaLnFeWO6 (Ln = La, Nd) perovskites", Inorganic Chemistry 52, 12482-12491 (2013).

162

Conference on New Frontiers in Neutron Macromolecular Crystallography  

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

systems being studied by x-ray diffraction. The advent of the Spallation Neutron Source (SNS) with over an order of magnitude increase in neutron flux, in combination with advances...

163

Diffraction Metrology and Standards  

Science Conference Proceedings (OSTI)

... and X-ray diffraction on two different synchrotron beamlines, at energies of 25 ... that allowed for the calibration of both line position and intensity as a ...

2012-10-09T23:59:59.000Z

164

X-ray and Neutron Studies of Fluids in Confinement  

Science Conference Proceedings (OSTI)

In-Situ Neutron Diffraction and Crystal Plasticity Modeling of a-Uranium In-Situ Studies of the ... Thermal Residual Stresses and Strains in Depleted Uranium.

165

What Neutrons Tell Us about Magnetic Shape Memory Materials?  

Science Conference Proceedings (OSTI)

In-Situ Neutron Diffraction and Crystal Plasticity Modeling of a-Uranium In-Situ Studies of the ... Thermal Residual Stresses and Strains in Depleted Uranium.

166

Powder Metallurgy and Additive Manufacturing of Titanium Powders  

Science Conference Proceedings (OSTI)

Composition Design of Multi-Component ?-Ti Alloys Based on a Cluster Model Consolidation of Blended Titanium/Magnesium Powders by Microwave Processing ... Rheological Properties of Feedstock Composed of Titanium Alloy Powder...

167

Diffraction Metrology and Standards  

E-Print Network (OSTI)

. Objective Impact and Customers · Our primary impact is the enhancement of the measurement capability certification. · Primary customers are the International Center for Diffraction Data (ICDD) and X-ray instrument and Engineering Laboratory Diffraction techniques can provide data on a number of sample characteristics

168

Diffraction Results from CDF  

Science Conference Proceedings (OSTI)

We present final results by the CDF II collaboration on diffractive W and Z production, report on the status of ongoing analyses on diffractive dijet production and on rapidity gaps between jets, and briefly summarize results obtained on exclusive production pointing to their relevance to calibrating theoretical models used to predict exclusive Higgs-boson production at the LHC.

Goulianos, Konstantin

2012-04-01T23:59:59.000Z

169

Method to blend separator powders  

DOE Patents (OSTI)

A method for making a blended powder mixture, whereby two or more powders are mixed in a container with a liquid selected from nitrogen or short-chain alcohols, where at least one of the powders has an angle of repose greater than approximately 50 degrees. The method is useful in preparing blended powders of Li halides and MgO for use in the preparation of thermal battery separators.

Guidotti, Ronald A. (Albuquerque, NM); Andazola, Arthur H. (Albuquerque, NM); Reinhardt, Frederick W. (Albuquerque, NM)

2007-12-04T23:59:59.000Z

170

Powder Metallurgy Processing and Products  

Science Conference Proceedings (OSTI)

About this Symposium. Meeting, Materials Science & Technology 2012. Symposium, Powder Metallurgy Processing and Products. Sponsorship. Organizer(s)...

171

Dirac Kirchhoff diffraction theory  

E-Print Network (OSTI)

Kirchhoff's scalar diffraction theory is applied throughout photon and electron optics. It is based on the stationary electromagnetic or Schr\\"odinger wave equation, and is useful in describing interference phenomena for both light and matter waves. Here, Kirchhoff's diffraction theory is derived from the relativistic Dirac equation, thus reformulated to work on Dirac spinors. The parallels with the "classic" scalar theory are highlighted, and a basic interpretation of the result obtained for the Fraunhofer diffraction limit is given. The goal of this paper is to emphasize the similarity between the two equations on the most fundamental level.

Ruben Van Boxem; Bart Partoens; Jo Verbeeck

2013-03-05T23:59:59.000Z

172

Dirac Kirchhoff diffraction theory  

E-Print Network (OSTI)

Kirchhoff's scalar diffraction theory is applied throughout photon and electron optics. It is based on the stationary electromagnetic or Schr\\"odinger wave equation, and is useful in describing interference phenomena for both light and matter waves. Here, Kirchhoff's diffraction theory is derived from the relativistic Dirac equation, thus reformulated to work on Dirac spinors. The parallels with the "classic" scalar theory are highlighted, and a basic interpretation of the result obtained for the Fraunhofer diffraction limit is given. The goal of this paper is to emphasize the similarity between the two equations on the most fundamental level.

Van Boxem, Ruben; Verbeeck, Jo

2013-01-01T23:59:59.000Z

173

Multilayer dielectric diffraction gratings  

DOE Patents (OSTI)

The design and fabrication of dielectric grating structures with high diffraction efficiency used in reflection or transmission is described. By forming a multilayer structure of alternating index dielectric materials and placing a grating structure on top of the multilayer, a diffraction grating of adjustable efficiency, and variable optical bandwidth can be obtained. Diffraction efficiency into the first order in reflection varying between 1 and 98 percent has been achieved by controlling the design of the multilayer and the depth, shape, and material comprising the grooves of the grating structure. Methods for fabricating these gratings without the use of ion etching techniques are described. 7 figs.

Perry, M.D.; Britten, J.A.; Nguyen, H.T.; Boyd, R.; Shore, B.W.

1999-05-25T23:59:59.000Z

174

Multilayer dielectric diffraction gratings  

DOE Patents (OSTI)

The design and fabrication of dielectric grating structures with high diffraction efficiency used in reflection or transmission is described. By forming a multilayer structure of alternating index dielectric materials and placing a grating structure on top of the multilayer, a diffraction grating of adjustable efficiency, and variable optical bandwidth can be obtained. Diffraction efficiency into the first order in reflection varying between 1 and 98 percent has been achieved by controlling the design of the multilayer and the depth, shape, and material comprising the grooves of the grating structure. Methods for fabricating these gratings without the use of ion etching techniques are described.

Perry, Michael D. (Livermore, CA); Britten, Jerald A. (Oakley, CA); Nguyen, Hoang T. (Livermore, CA); Boyd, Robert (Livermore, CA); Shore, Bruce W. (Livermore, CA)

1999-01-01T23:59:59.000Z

175

X-Ray Diffraction on NIF  

SciTech Connect

The National Ignition Facility (NIF) is currently a 192 beam, 1.6 MJ laser. NIF Ramp-Compression Experiments have already made the relevant exo-planet pressure range from 1 to 50 Mbar accessible. We Proposed to Study Carbon Phases by X-Ray Diffraction on NIF. Just a few years ago, ultra-high pressure phase diagrams for materials were very 'simple'. New experiments and theories point out surprising and decidedly complex behavior at the highest pressures considered. High pressures phases of aluminum are also predicted to be complex. Recent metadynamics survey of carbon proposed a dynamic pathway among multiple phases. We need to develop diagnostics and techniques to explore this new regime of highly compressed matter science. X-Ray Diffraction - Understand the phase diagram/EOS/strength/texture of materials to 10's of Mbar. Strategy and physics goals: (1) Powder diffraction; (2) Begin with diamond; (3) Continue with metals etc.; (4) Explore phase diagrams; (5) Develop liquid diffraction; and (6) Reduce background/improve resolution.

Eggert, J H; Wark, J

2012-02-15T23:59:59.000Z

176

Diffraction at TOTEM  

E-Print Network (OSTI)

The TOTEM experiment at the LHC measures the total proton-proton cross section with the luminosity-independent method and the elastic proton-proton cross-section over a wide |t|-range. It also performs a comprehensive study of diffraction, spanning from cross-section measurements of individual diffractive processes to the analysis of their event topologies. Hard diffraction will be studied in collaboration with CMS taking advantage of the large common rapidity coverage for charged and neutral particle detection and the large variety of trigger possibilities even at large luminosities. TOTEM will take data under all LHC beam conditions including standard high luminosity runs to maximize its physics reach. This contribution describes the main features of the TOTEM physics programme including measurements to be made in the early LHC runs. In addition, a novel scheme to extend the diffractive proton acceptance for high luminosity runs by installing proton detectors at IP3 is described.

G. Antchev; P. Aspell; V. Avati; M. G. Bagliesi; V. Berardi; M. Berretti; U. Bottigli; M. Bozzo; E. Brucken; A. Buzzo; F. Cafagna; M. Calicchio; M. G. Catanesi; P. L. Catastini; R. Cecchi; M. A. Ciocci; M. Deile; E. Dimovasili; K. Eggert; V. Eremin; F. Ferro; F. Garcia; S. Giani; V. Greco; J. Heino; T. Hilden; J. Kaspar; J. Kopal; V. Kundrat; K. Kurvinen; S. Lami; G. Latino; R. Lauhakangas; E. Lippmaa; M. Lokajicek; M. Lo Vetere; F. Lucas Rodriguez; M. Macri; G. Magazzu; M. Meucci; S. Minutoli; H. Niewiadomski; E. Noschis; G. Notarnicola; E. Oliveri; F. Oljemark; R. Orava; M. Oriunno; K. Osterberg; P. Palazzi; E. Pedreschi; J. Petajajarvi; M. Quinto; E. Radermacher; E. Radicioni; F. Ravotti; G. Rella; E. Robutti; L. Ropelewski; G. Ruggiero; A. Rummel; H. Saarikko; G. Sanguinetti; A. Santroni; A. Scribano; G. Sette; W. Snoeys; F. Spinella; P. Squillacioti; A. Ster; C. Taylor; A. Trummal; N. Turini; J. Whitmore; J. Wu

2008-12-17T23:59:59.000Z

177

Reflective diffraction grating  

DOE Patents (OSTI)

Reflective diffraction grating. A focused ion beam (FIB) micromilling apparatus is used to store color images in a durable medium by milling away portions of the surface of the medium to produce a reflective diffraction grating with blazed pits. The images are retrieved by exposing the surface of the grating to polychromatic light from a particular incident bearing and observing the light reflected by the surface from specified reception bearing.

Lamartine, Bruce C. (Los Alamos, NM)

2003-06-24T23:59:59.000Z

178

Preparation of superconductor precursor powders  

DOE Patents (OSTI)

A process for the preparation of a precursor metallic powder composition for use in the subsequent formation of a superconductor. The process comprises the steps of providing an electrodeposition bath comprising an electrolyte medium and a cathode substrate electrode, and providing to the bath one or more soluble salts of one or more respective metals which are capable of exhibiting superconductor properties upon subsequent appropriate treatment. The bath is continually energized to cause the metallic and/or reduced particles formed at the electrode to drop as a powder from the electrode into the bath, and this powder, which is a precursor powder for superconductor production, is recovered from the bath for subsequent treatment. The process permits direct inclusion of all metals in the preparation of the precursor powder, and yields an amorphous product mixed on an atomic scale to thereby impart inherent high reactivity. Superconductors which can be formed from the precursor powder include pellet and powder-in-tube products.

Bhattacharya, Raghunath (Littleton, CO)

1998-01-01T23:59:59.000Z

179

Glossary Term - Neutron Emission  

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

Neutron Previous Term (Neutron) Glossary Main Index Next Term (Niobe) Niobe Neutron Emission After neutron emission, an atom contains one less neutron. Neutron emission is one...

180

Definition: Portable X-Ray Diffraction (XRD) | Open Energy Information  

Open Energy Info (EERE)

Definition Definition Edit with form History Facebook icon Twitter icon » Definition: Portable X-Ray Diffraction (XRD) Jump to: navigation, search Dictionary.png Portable X-Ray Diffraction (XRD) Portable X-Ray Diffraction (XRD) is a field-based technique that can be used for identification of crystalline materials and analysis of unit cell dimensions. Portable XRD analysis is similar to X-ray powder diffraction, which has traditionally been used in geology, environmental science, material science, and engineering to rapidly identify unknown crystalline substances. Portable XRD analysis allows for simpler sample preparation, faster analytical times than traditional methods (less than 2 minutes), and can be performed at the sampling site in the field. A pure, finely ground

Note: This page contains sample records for the topic "neutron powder diffraction" 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

Powder Consolidation and Properties II  

Science Conference Proceedings (OSTI)

Feb 16, 2010... energy efficient due to the possibility of direct microwave heating of the titanium powder augmented by hybrid heating in a ceramic casket.

182

Recent Developments in Powder Metallurgy  

SciTech Connect

Brief notes from a meeting between NAA and S. B. Roboff, Sylvania Electric Products, regarding the important developments in powder metallurgy fuels and reactor materials.

Hayward, B.R.

1953-06-30T23:59:59.000Z

183

Powder Consolidation and Properties I  

Science Conference Proceedings (OSTI)

Feb 16, 2010 ... Making Titanium Powder Metallurgy a Viable Alternative to Wrought for Manufacturing: James Sears1; 1South Dakota School of Mines &...

184

EMSL: Capabilities: Spectroscopy and Diffraction  

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

Spectroscopy and Diffraction Spectroscopy and Diffraction Additional Information Meet the Spectroscopy and Diffraction Experts Related EMSL User Projects Spectroscopy and Diffraction Tools are Applied to all Science Themes Tutorial: XPS Tools for Surface Analysis Spectroscopy and Diffraction brochure EMSL's suite of spectroscopy and diffraction instruments allows users to study solid-, liquid-, and gas-phase sample structure and composition with remarkable resolution. Ideal for integrated studies, spectrometers and diffractometers are easily coupled with EMSL's computational and modeling capabilities, allowing users to apply a multifaceted research approach for experimental data interpretation and gain fundamental understanding of scientific problems. At EMSL, spectroscopy and diffraction instruments are

185

Nuclear Shadowing and Diffraction  

E-Print Network (OSTI)

The relation between diffraction in lepton-proton collisions and shadowing of nuclear structure functions which arises from Gribov inelastic shadowing, is described. A model realizing such relation, which produces a parameter-free description of experimental data on nuclear structure functions at small $x$, is presented. The application to the description of multiplicities in nuclear collisions is discussed and related to other approaches.

J. L. Albacete; N. Armesto; A. Capella; A. B. Kaidalov; C. A. Salgado

2004-10-12T23:59:59.000Z

186

Neutron Radiography  

Science Conference Proceedings (OSTI)

Table 8   Characteristics of neutron radiography at various neutron-energy ranges...Good discrimination between materials and ready availability

187

Neutron Sources  

Science Conference Proceedings (OSTI)

Table 1   Characteristics of neutron radiography at various neutron-energy ranges...Good discrimination between materials, and ready

188

Investigating Ultrasonic Diffraction Grating Spectroscopy and ...  

Investigating Ultrasonic Diffraction Grating Spectroscopy and Reflection Techniques for Characterization Slurry Properties Investigating Ultrasonic Diffraction Grating

189

Glossary Term - Neutron  

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

Neutrino Previous Term (Neutrino) Glossary Main Index Next Term (Neutron Emission) Neutron Emission Neutron A Neutron Neutrons are uncharged particles found within atomic nuclei....

190

About Neutrons  

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

Neutron Basics Neutron Basics A neutron is one of the fundamental particles that make up matter. This uncharged particle exists in the nucleus of a typical atom, along with its positively charged counterpart, the proton. Protons and neutrons each have about the same mass, and both can exist as free particles away from the nucleus. In the universe, neutrons are abundant, making up more than half of all visible matter. Find Out What a Neutron Is Youtube icon Properties of Neutrons How Can Neutrons Be Used for Research? Image of glucose movement in plants Neutron imaging techniques have been able to determine the precise movement of glucose in plants. This knowledge can help scientists better understand how biomass can be efficiently converted into fuel. Neutrons have many properties that make them ideal for certain types of

191

Preparation of superconductor precursor powders  

DOE Patents (OSTI)

A process for the preparation of a precursor metallic powder composition for use in the subsequent formation of a superconductor. The process comprises the steps of providing an electrodeposition bath comprising an electrolyte medium and a cathode substrate electrode, and providing to the bath one or more soluble salts of one or more respective metals, such as nitrate salts of thallium, barium, calcium, and copper, which are capable of exhibiting superconductor properties upon subsequent appropriate treatment. The bath is continually energized to cause the metallic particles formed at the electrode to drop as a powder from the electrode into the bath, and this powder, which is a precursor powder for superconductor production, is recovered from the bath for subsequent treatment. The process permits direct inclusion of thallium in the preparation of the precursor powder, and yields an amorphous product mixed on an atomic scale to thereby impart inherent high reactivity. Superconductors which can be formed from the precursor powder include pellet and powder-in-tube products.

Bhattacharya, Raghunath (Littleton, CO); Blaugher, Richard D. (Evergreen, CO)

1995-01-01T23:59:59.000Z

192

Preparation of superconductor precursor powders  

DOE Patents (OSTI)

A process for the preparation of a precursor metallic powder composition for use in the subsequent formation of a superconductor. The process comprises the steps of providing an electrodeposition bath comprising an electrolyte medium and a cathode substrate electrode, and providing to the bath one or more soluble salts of one or more respective metals which are capable of exhibiting superconductor properties upon subsequent appropriate treatment. The bath is continually energized to cause the metallic and/or reduced particles formed at the electrode to drop as a powder from the electrode into the bath, and this powder, which is a precursor powder for superconductor production, is recovered from the bath for subsequent treatment. The process permits direct inclusion of all metals in the preparation of the precursor powder, and yields an amorphous product mixed on an atomic scale to thereby impart inherent high reactivity. Superconductors which can be formed from the precursor powder include pellet and powder-in-tube products. 7 figs.

Bhattacharya, R.

1998-08-04T23:59:59.000Z

193

Effect of Powder Cleanliness on the Fatigue Behavior of Powder ...  

Science Conference Proceedings (OSTI)

quantitative fractography, and heavy liquid separation, were evaluated and .... The size distribution of natural inclusions recovered from the same unseeded powder ..... the United Engineering Foundation Conference on Gas Turbine. Engines...

194

X-ray diffraction data for plutonium compounds  

Science Conference Proceedings (OSTI)

This work is a compilation of x-ray diffraction information relating to powder photographs of plutonium compounds. The information is presented in a format and style substantially as recommended by the International Centre for Diffraction Data. The Los Alamos National Laboratory has been very much involved in the study of the properties of plutonium and its compounds. During the past 45 years the Powder Diffraction File of the Laboratory has grown to more than 20,000 films. F.H. Ellinger and his coworkers have used this data to establish a large number of plutonium binary phase diagrams. A phase diagram, however, should never be regarded as really complete as new techniques of alloy preparation or x-ray and optical metallography continually discover new phases that must be incorporated in the diagram. In addition to the phase diagrams, the crystal structure of a number of plutonium intermetallic compounds have been determined at Los Alamos. Due to the importance of plutonium as a representative of the actinide series of elements, it is deemed advisable to have available information on the x-ray diffraction of plutonium and its compounds for the purpose of identification of these materials. It is hoped that the information presented here will be of value in this regard.

Roof, R.B.

1989-10-01T23:59:59.000Z

195

Ultrafine Hydrogen Storage Powders - Energy Innovation Portal  

Patent 6,074,453: Ultrafine hydrogen storage powders A method of making hydrogen storage powder resistant to fracture in service involves forming a melt having the ...

196

Particle and feeding characteristics of biomass powders.  

E-Print Network (OSTI)

?? Milling of biomass is a necessary key step in suspension gasification or powder combustion. Milled biomass powders are often cohesive, have low bulk density (more)

Falk, Joel

2013-01-01T23:59:59.000Z

197

Results on hard diffractive production  

Science Conference Proceedings (OSTI)

The results of experiments at hadron colliders probing the structure of the pomeron through hard diffraction are reviewed. Some results on deep inelastic diffractive scattering obtained at HERA are also discussed and placed in perspective. By using a properly normalized pomeron flux factor in single diffraction dissociation as dictated by unitarity

Konstantin Goulianos; The CDF Collaboration

1996-01-01T23:59:59.000Z

198

Rotary powder feed through apparatus  

DOE Patents (OSTI)

A device for increasing the uniformity of solids within a solids fabrication system, such as a direct light fabrication (DLF) system in which gas entrained powders are passed through the focal point of a moving high-power light which fuses the particles in the powder to a surface being built up in layers. The invention provides a feed through interface wherein gas entrained powders input from stationary input lines are coupled to a rotating head of the fabrication system. The invention eliminates the need to provide additional slack in the feed lines to accommodate head rotation, and therefore reduces feed line bending movements which induce non-uniform feeding of gas entrained powder to a rotating head.

Lewis, Gary K. (Los Alamos, NM); Less, Richard M. (Los Alamos, NM)

2001-01-01T23:59:59.000Z

199

Comparison of Powder Processing Methods  

Science Conference Proceedings (OSTI)

Table 5   Application of powder processing methods...wrought Greater than wrought Equal to wrought Price per pound $0.50??5.00 $1??10 >$100 $1??5...

200

Ceramic oxide powders and the formation thereof  

DOE Patents (OSTI)

Ceramic oxide powders and a method for their preparation. Ceramic oxide powders are obtained using a flame process whereby two or more precursors of ceramic oxides are introduced into a counterflow diffusion flame burner wherein said precursors are converted into ceramic oxide powders. The morphology, particle size, and crystalline form of the ceramic oxide powders are determined by process conditions.

Katz, Joseph L. (Baltimore, MD); Hung, Cheng-Hung (Baltimore, MD)

1993-01-01T23:59:59.000Z

Note: This page contains sample records for the topic "neutron powder diffraction" 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.
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201

Ceramic oxide powders and the formation thereof  

DOE Patents (OSTI)

Ceramic oxide powders and a method for their preparation. Ceramic oxide powders are obtained using a flame process whereby two or more precursors of ceramic oxides are introduced into a counterflow diffusion flame burner wherein said precursors are converted into ceramic oxide powders. The morphology, particle size, and crystalline form of the ceramic oxide powders are determined by process conditions. 14 figures.

Katz, J.L.; Chenghung Hung.

1993-12-07T23:59:59.000Z

202

Diffraction at HERA  

E-Print Network (OSTI)

Between 1992 and 2007, the HERA accelerator provided $ep$ collisions at center of mass energies beyond $300 \\ {\\rm GeV}$ at the interaction points of the H1 and ZEUS experiments. Interesting results to emerge relate to the newly accessed field of perturbative strong interaction physics at low Bjorken-$x$, where parton densities become extremely large. Questions arise as to how and where non-linear dynamics tame the parton density growth and challenging features such as geometric scaling are observed. Central to this low $x$ physics landscape is a high rate of diffractive processes, in which a colorless exchange takes place and the proton remains intact. A review is given for main results obtained by H1 and ZEUS experiments in this field.

Schoeffel, Laurent

2011-01-01T23:59:59.000Z

203

Neutron dosimetry  

DOE Patents (OSTI)

A method of measuring neutron radiation within a nuclear reactor is provided. A sintered oxide wire is disposed within the reactor and exposed to neutron radiation. The induced radioactivity is measured to provide an indication of the neutron energy and flux within the reactor.

Quinby, Thomas C. (Kingston, TN)

1976-07-27T23:59:59.000Z

204

Awards 2007 | ORNL Neutron Sciences  

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

7 7 Staff Awards: 2007 Chakoumakos elected MSA Fellow Bryan Chakoumakos Neutron scientist Bryan Chakoumakos was recently elected a fellow of the Mineralogical Society of America. A member of the Neutron Scattering Science Division, Bryan leads the Single-Crystal Diffraction Group. The group has five neutron scattering instruments in various stages of design and construction, located at HFIR and SNS. The MSA was founded in 1919 and, among other goals, encourages fundamental research on natural materials and supports education through its publications, educational grants, and courses. Pharos Neutron Detector System Researchers at the Department of Energy's Oak Ridge National Laboratory have won six R&D 100 Awards, given annually by R&D Magazine to the year's

205

POWGEN - The Powder Diffractometer at SNS - ORNL Neutron Sciences  

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

but are not limited to, structural studies of magnetic materials such as high-Tc superconductors, metal-insulator phase transitions, charge and orbital ordering transitions, and...

206

PROCESS OF FORMING POWDERED MATERIAL  

DOE Patents (OSTI)

A process of forming high-density compacts of a powdered ceramic material is described by agglomerating the powdered ceramic material with a heat- decompossble binder, adding a heat-decompossble lubricant to the agglomerated material, placing a quantity of the material into a die cavity, pressing the material to form a compact, pretreating the compacts in a nonoxidizing atmosphere to remove the binder and lubricant, and sintering the compacts. When this process is used for making nuclear reactor fuel elements, the ceramic material is an oxide powder of a fissionsble material and after forming, the compacts are placed in a cladding tube which is closed at its ends by vapor tight end caps, so that the sintered compacts are held in close contact with each other and with the interior wall of the cladding tube.

Glatter, J.; Schaner, B.E.

1961-07-14T23:59:59.000Z

207

NIST Diffraction effects in radiometry  

Science Conference Proceedings (OSTI)

... of the overall effort to understand the role of solar variation in ... diffraction effects at short wavelengths (relevant to spectral power measurements) and ...

2011-01-12T23:59:59.000Z

208

TUTORIALS: Bragg's Law and Diffraction  

Science Conference Proceedings (OSTI)

Jul 8, 2007 ... CITATION: "Bragg's Law and Diffraction: How waves reveal the atomic structure of crystals," Project Java, State University of New York at Stony...

209

Electrically-programmable diffraction grating  

DOE Patents (OSTI)

An electrically-programmable diffraction grating. The programmable grating includes a substrate having a plurality of electrodes formed thereon and a moveable grating element above each of the electrodes. The grating elements are electrostatically programmable to form a diffraction grating for diffracting an incident beam of light as it is reflected from the upper surfaces of the grating elements. The programmable diffraction grating, formed by a micromachining process, has applications for optical information processing (e.g. optical correlators and computers), for multiplexing and demultiplexing a plurality of light beams of different wavelengths (e.g. for optical fiber communications), and for forming spectrometers (e.g. correlation and scanning spectrometers).

Ricco, Antonio J. (Albuquerque, NM); Butler, Michael A. (Albuquerque, NM); Sinclair, Michael B. (Albuquerque, NM); Senturia, Stephen D. (Brookline, MA)

1998-01-01T23:59:59.000Z

210

X-ray diffraction data for plutonium compounds  

Science Conference Proceedings (OSTI)

This work is a compilation of x-ray diffraction information relating to powder photographs of plutonium compounds. The information is presented in a format and style substantially as recommended by the International Center for Diffraction Data. Los Alamos National Laboratory has been involved in the study of the properties of plutonium and its compounds. During the past 45 years, the Powder Diffraction File of the Laboratory has grown to more than 20,000 films. F.H. Ellinger and his coworkers have used this data to establish a large number of plutonium binary phase diagrams. These phase diagrams have been published in a special report of the Laboratory, LA-3870, Constitution of Plutonium Alloys,'' authored by F.H. Ellinger, W.N. Miner, D.R. O'Boyle, and F.W. Schonfeld. A phase diagram, however, should never be regarded as really complete as new techniques of alloy preparation or x-ray and optical metallography continually discover new phases that must be incorporated in the diagram. In addition to the phase diagrams, the crystal structures of a number of plutonium intermetallic compounds have been determined at Los Alamos and published in the general literature by D.T. Cromer, A.C. Larson, and R.B. Roof over the last 35 years.

Roof, R.B.

1991-06-01T23:59:59.000Z

211

Superconductivity | ORNL Neutron Sciences  

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

Research Highlights Research Highlights Superconductivity Neutron diffraction reveals semiconducting phase and contributes to new understanding of iron-based superconductors Contact: Huibo Cao New VULCAN tests of Japanese cable for US ITER's central magnet system (2012) Contact: Ke An ARCS maps collaborative magnetic spin behavior in iron telluride (2011) Published Work: "Unconventional Temperature Enhanced Magnetism in Fe1:1Te" Contact: Igor Zaliznyak Doug Scalapino discusses "common thread" linking unconventional superconducting materials (2011) Contact: Douglas Scalapino Materials Engineering Research at SNS Helps International Collaboration on Fusion Energy Scientists and engineers at ORNL are working with the ITER Organization and the Japanese Atomic Energy Agency to resolve issues with a critical

212

Diffraction: 100 Years and Beyond  

Science Conference Proceedings (OSTI)

Mar 4, 2013 ... Neutron and X-Ray Scattering Studies of Solid Sorbents for Carbon Capture: Andrew Allen1; Laura Espinal1; Winnie Wong-Ng1; Martin...

213

Diffraction Studies of Phase Transtions  

Science Conference Proceedings (OSTI)

Mar 6, 2013 ... Neutron and X-Ray Studies of Advanced Materials VI: Centennial and ..... double crystal monochromator, and at the spallation source at STFC...

214

Preparing PLA Powders for Powder-Based Processing Using a ...  

Science Conference Proceedings (OSTI)

Of late, an important fabrication technique for producing complex shapes has emerged: ... The mechanism of powder formation can be explained by the relative solubility of ... Application of Polymer-Based Microfluidic Devices for the Selection and ... Biologically Inspired Origami (BIO) Paper for Tissue Engineering Scaffolds.

215

Test data for the calculation of powder paterns for intermetallic phases  

Science Conference Proceedings (OSTI)

Powder diffraction patterns are often calculated from structural parameters to assist in the identification of materials. To ensure that powder pattern calculations are correct, it is useful to have data to test the computer program doing the calculations. this paper contains test data for each of the crystallographic point groups and 63 of the 230 space groups. An important feature of the data is that many tests involve two high-symmetry structures (sodium and magnesium) that are set in successively lower-symmetry space groups. Thus, the calculated powder intensities for sodium, for example, are identical whatever the setting is. Though the data were chosen to be especially useful for the calculation of the powder patterns of metals and intermetallic compounds, the data have wider utility.

Calvert, L.D.; Mueller, M.H. [ (deceased); Wallace, P.L. [Los Alamos National Lab., NM (United States); Huang, J.A. [San Jose, CA (United States); Kaduk, J.A. [Amoco Research Center, Naperville, Il (United States); Dann, J.N. [Osram Sylvania, Inc., Towanda, PA (United States); Roberts, A.C [Geological Survey of Canada, Ottawa, Ontario (Canada)

1996-09-01T23:59:59.000Z

216

Neutron diffraction reveals promising new phosphor for white...  

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

Source at Argonne National Laboratory to decipher the atomic structure in a new phosphor. Light bulbs, flashlights, and car headlights are all a lot brighter than they used to be....

217

Time Resolved Neutron Diffraction Studies of Hydrogen Storage ...  

Science Conference Proceedings (OSTI)

ORNL/SNS is managed by UT-Battelle, LLC, for the U.S. Department of Energy under contract DE-AC05-00OR22725. Work at ... Definite: A CD-only volume...

218

In Situ Neutron Diffraction Measurements of the Shear Moduli Ghkl ...  

Science Conference Proceedings (OSTI)

At ORNL's High Flux Isotope Reactor instrument NRSF2, the load frame was integrated with the sample positioner, and the load ... Definite: A CD-only volume ...

219

Neutron Diffraction Studies of Residual Stresses around Gouges ...  

Science Conference Proceedings (OSTI)

Gouges contained in pipeline sections were termed BEA161 (primarily a gouge with little denting), and BEA178 (mild gouging, very large dent). Measurements...

220

Neutron Diffraction Investigation of Friction-Stir Processed ...  

Science Conference Proceedings (OSTI)

... Processed Aluminum and Magnesium Alloys. Wanchuck (Chuck) Woo, University of Tennessee and Oak Ridge National Lab. ...

Note: This page contains sample records for the topic "neutron powder diffraction" 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

In-Situ Neutron Diffraction Study of Nanobainitic Steels in ...  

Science Conference Proceedings (OSTI)

The same characteristics were also studied via transmission electron microscopy and were found ... Line Profile Analysis of Plastically Deformed Single Crystals.

222

Polymer quenched prealloyed metal powder  

DOE Patents (OSTI)

A powder metallurgical process of preparing a sheet from a powder having an intermetallic alloy composition such as an iron, nickel or titanium aluminide. The sheet can be manufactured into electrical resistance heating elements having improved room temperature ductility, electrical resistivity, cyclic fatigue resistance, high temperature oxidation resistance, low and high temperature strength, and/or resistance to high temperature sagging. The iron aluminide has an entirely ferritic microstructure which is free of austenite and can include, in weight %, 4 to 32% Al, and optional additions such as .ltoreq.1% Cr, .gtoreq.0.05% Zr .ltoreq.2% Ti, .ltoreq.2% Mo, .ltoreq.1% Ni, .ltoreq.0.75% C, .ltoreq.0.1% B, .ltoreq.1% submicron oxide particles and/or electrically insulating or electrically conductive covalent ceramic particles, .ltoreq.1% rare earth metal, and/or .ltoreq.3 % Cu. The process includes forming a non-densified metal sheet by consolidating a powder having an intermetallic alloy composition such as by roll compaction, tape casting or plasma spraying, forming a cold rolled sheet by cold rolling the non-densified metal sheet so as to increase the density and reduce the thickness thereof and annealing the cold rolled sheet. The powder can be a water, polymer or gas atomized powder which is subjecting to sieving and/or blending with a binder prior to the consolidation step. After the consolidation step, the sheet can be partially sintered. The cold rolling and/or annealing steps can be repeated to achieve the desired sheet thickness and properties. The annealing can be carried out in a vacuum furnace with a vacuum or inert atmosphere. During final annealing, the cold rolled sheet recrystallizes to an average grain size of about 10 to 30 .mu.m. Final stress relief annealing can be carried out in the B2 phase temperature range.

Hajaligol, Mohammad R. (Midlothian, VA); Fleischhauer, Grier (Midlothian, VA); German, Randall M. (State College, PA)

2001-01-01T23:59:59.000Z

223

DIFFERENTIAL NEUTRON THERMALIZATION. Annual Summary Report, October 1, 1961 through September 30, 1962  

DOE Green Energy (OSTI)

Experimental and theoretical work on the interaction mechanisms by which neutrons exchange energy with H atoms involves treating neutron thermalization as neutron interactions with energy levels in the atoms. Cold moderators are presently being studied in order to optimize the source of cold neutrons. Cold neutrons are provided from an accelerator arrangement that directs electrons against a Fansteel target producing fast neutrons. Thermal neutrons, produced by moderation of fast neutrons, are passed through a chopper. Several moderators are evaluated, and neutron emission time measurements by crystal diffraction and beam chopper techniques point out emission time dependence on thickness, moderator, and temperature. The neutron beam chopper used presently is described, and results of neutron scattering by liquid para- and orthohydrogen are displayed and compared with theoretical predictions made with a perfect hydrogen gas model. Inelastic scattering of neutrons by liquid H is discussed, and theoretical and experimental results of inelastic scattering by polyethylene are also included. (D.C.W.)

Whittemore, W L

1962-11-28T23:59:59.000Z

224

Neutron Sources  

Science Conference Proceedings (OSTI)

... for Neutron Reaction Rate Measurements, JA Grundl, V. Spiegel, CM Eisenhauer, HT Heaton II, DM Gilliam (NBS), and J. Bigelow (ORNL), Nucl. ...

2013-07-27T23:59:59.000Z

225

Iowa Powder Atomization Technologies, Inc. | Department of Energy  

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

Iowa Powder Atomization Technologies, Inc. America's Next Top Energy Innovator Challenge 6067 likes Iowa Powder Atomization Technologies, Inc. Ames Laboratory Iowa Powder...

226

Intradermal needle-free powdered drug injection  

E-Print Network (OSTI)

This thesis presents a new method for needle-free powdered drug injection. The design, construction, and testing of a bench-top helium-powered device capable of delivering powder to controllable depths within the dermis ...

Liu, John (John Hsiao-Yung)

2012-01-01T23:59:59.000Z

227

SHAPING AND FORMING OF HIGH PERFORMANCE POWDER ...  

Science Conference Proceedings (OSTI)

A DENSIFICATION CONSTITUTIVE MODEL FOR POWDER BASED ALUMINUM MATRIX COMPOSITES MATERIALS: Erik J. Jilinsk, John J. Lewandowski,...

228

Advanced Titanium Powder Processing - Additive Layer ...  

Science Conference Proceedings (OSTI)

Symposium, Cost Affordable Titanium IV. Presentation Title, Advanced Titanium Powder Processing - Additive Layer Manufacturing (ALM) and Metal Injection...

229

Storage of very cold neutrons in a trap with nano-structured walls  

E-Print Network (OSTI)

We report on storage of Very Cold Neutrons (VCN) in a trap with walls containing powder of diamond nanoparticles. The efficient VCN reflection is provided by multiple diffusive elastic scattering of VCN at single nanoparticles in powder. The VCN storage times are sufficiently long for accumulating large density of neutrons with complete VCN energy range of up to a few times 10(-4) eV. Methods for further improvements of VCN storage times are discussed.

E. V. Lychagin; A. Yu. Muzychka; V. V. Nesvizhevsky; G. Pignol; K. V. Protasov; A. V. Strelkov

2008-12-09T23:59:59.000Z

230

Neutronic reactor  

DOE Patents (OSTI)

A safety rod for a nuclear reactor has an inner end portion having a gamma absorption coefficient and neutron capture cross section approximately equal to those of the adjacent shield, a central portion containing materials of high neutron capture cross section and an outer end portion having a gamma absorption coefficient at least equal to that of the adjacent shield.

Wende, Charles W. J. (West Chester, PA)

1976-08-17T23:59:59.000Z

231

Electrically-programmable diffraction grating  

DOE Patents (OSTI)

An electrically-programmable diffraction grating is disclosed. The programmable grating includes a substrate having a plurality of electrodes formed thereon and a moveable grating element above each of the electrodes. The grating elements are electrostatically programmable to form a diffraction grating for diffracting an incident beam of light as it is reflected from the upper surfaces of the grating elements. The programmable diffraction grating, formed by a micromachining process, has applications for optical information processing (e.g. optical correlators and computers), for multiplexing and demultiplexing a plurality of light beams of different wavelengths (e.g. for optical fiber communications), and for forming spectrometers (e.g. correlation and scanning spectrometers). 14 figs.

Ricco, A.J.; Butler, M.A.; Sinclair, M.B.; Senturia, S.D.

1998-05-26T23:59:59.000Z

232

Search for neutrons from deuterated palladium subject to high electrical currents  

Science Conference Proceedings (OSTI)

Tritium has been detected evolving from samples of deuteriated palladium wires and powders subject to pulsed high voltage at Los Alamos. They wanted to measure whether these samples were emitting neutrons. The idea of pulsing current through the wires and powders was to drive the deuterium in and out by rapid electrical heating. With promising tritium results in hand, the experiments were prepared at Los Alamos, and then taken to BYU and run in the neutron detector located in a tunnel in Provo canyon under 35 m of rock and dirt overburden. The neutrons detector and sample setup are described. Results including total neutron counts, time distributions, and an indication of the energy distributions are discussed. The results do not provide compelling evidence of neutron production, but are not inconsistent with earlier measurements of neutrons and tritium. Difficulties in explaining the difference in tritium and neutron measurements are also discussed. Plans for further work are presented.

Taylor, S.F. [Los Alamos National Lab., NM (United States)]|[Brigham Young Univ., Provo, UT (United States); Claytor, T.N.; Tuggle, D.G. [Los Alamos National Lab., NM (United States); Jones, S.E. [Brigham Young Univ., Provo, UT (United States). Dept. of Physics and Astronomy

1994-04-01T23:59:59.000Z

233

Neutron source  

DOE Patents (OSTI)

A neutron source which is particularly useful for neutron radiography consists of a vessel containing a moderating media of relatively low moderating ratio, a flux trap including a moderating media of relatively high moderating ratio at the center of the vessel, a shell of depleted uranium dioxide surrounding the moderating media of relatively high moderating ratio, a plurality of guide tubes each containing a movable source of neutrons surrounding the flux trap, a neutron shield surrounding one part of each guide tube, and at least one collimator extending from the flux trap to the exterior of the neutron source. The shell of depleted uranium dioxide has a window provided with depleted uranium dioxide shutters for each collimator. Reflectors are provided above and below the flux trap and on the guide tubes away from the flux trap.

Cason, J.L. Jr.; Shaw, C.B.

1975-10-21T23:59:59.000Z

234

Compaction and Sintering of Mo Powders  

SciTech Connect

To support the development of Mo-99 production by NorthStar Medical Technologies, LLC, Mo metal powders were evaluated for compaction and sintering characteristics as they relate to Mo-100 accelerator target disk fabrication. Powders having a natural isotope distribution and enriched Mo-100 powder were examined. Various powder characteristics are shown to have an effect on both the compaction and sintering behavior. Natural Mo powders could be cold pressed directly to >90% density. All of the powders, including the Mo-100 samples, could be sintered after cold pressing to >90% density. As an example, a compacted Mo-100 disk reached 89.7% density (9.52 g/cm3) after sintering at 1000 C for 1 hr. in flowing Ar/4%H2. Higher sintering temperatures were required for other powder samples. The relationships between processing conditions and the resulting densities of consolidated Mo disks will be presented.

Nunn, Stephen D [ORNL; Kiggans, Jim [ORNL; Bryan, Chris [ORNL

2013-01-01T23:59:59.000Z

235

Laminated composite of magnetic alloy powder and ceramic ...  

Laminated composite of magnetic alloy powder and ceramic powder and process for making same United States Patent

236

ALICE diffractive physics in p-p and Pb-Pb collisions at the LHC  

SciTech Connect

The ALICE experiment at the Large Hadron Collider LHC is presently being commissioned. ALICE consists of a central barrel, a muon spectrometer and neutron calorimeters at 0 deg. Additional detectors for event classification and trigger purposes are located on both sides of the central barrel. The geometry of the ALICE detector allows the implementation of a diffractive double gap trigger by requiring two or more tracks in the central barrel but no activity in the event classification detectors. Some selected diffractive physics channels are discussed which become accessible by a double gap trigger. The interest of such diffractive measurements in proton-proton as well as in lead-lead collisions is outlined.

Schicker, R. [Phys. Inst., Philosophenweg 12, 69120 Heidelberg (Germany)

2009-03-23T23:59:59.000Z

237

Thermal neutron detection system  

DOE Patents (OSTI)

According to the present invention, a system for measuring a thermal neutron emission from a neutron source, has a reflector/moderator proximate the neutron source that reflects and moderates neutrons from the neutron source. The reflector/moderator further directs thermal neutrons toward an unmoderated thermal neutron detector.

Peurrung, Anthony J. (Richland, WA); Stromswold, David C. (West Richland, WA)

2000-01-01T23:59:59.000Z

238

Education | ORNL Neutron Sciences  

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

of the National Research Council. Full article ... Distance Learning Students Visit SNS Powder Diffractometer Students at the POWGEN Powder Diffractometer at SNS Ashfia Huq,...

239

NEUTRONIC REACTORS  

DOE Patents (OSTI)

A nuclear reactor is described wherein horizontal rods of thermal- neutron-fissionable material are disposed in a body of heavy water and extend through and are supported by spaced parallel walls of graphite.

Wigner, E.P.

1960-11-22T23:59:59.000Z

240

The impact of powder X-ray diffraction on mineral science ...  

Science Conference Proceedings (OSTI)

... Iron/Mn ores 55% Fe(Sishen) 20% Fe(Labrador trough) Fluorspar 9-10% (USGS) Ilmenite/rutile 8% (Hard Rock) 2-3% (Heavy minerals ...

2013-06-07T23:59:59.000Z

Note: This page contains sample records for the topic "neutron powder diffraction" 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

267_3_Powder_X-ray_Diffraction_of_Triglycerides_in_the_Study  

Science Conference Proceedings (OSTI)

AOCS Press, Urbana, IL 61802 2012 by AOCS Press. All rights reserved. No part of this PDF may be reproduced or transmitted in any form or by any means without written permission of the publisher. To order more AOCS products, please visit our web

242

NEUTRONIC REACTOR  

DOE Patents (OSTI)

A neutronic reactor in which neutron moderation is achieved primarily in its reflector is described. The reactor structure consists of a cylindrical central "island" of moderator and a spherical moderating reflector spaced therefrom, thereby providing an annular space. An essentially unmoderated liquid fuel is continuously passed through the annular space and undergoes fission while contained therein. The reactor, because of its small size, is particularly adapted for propulsion uses, including the propulsion of aircraft. (AEC)

Fraas, A.P.; Mills, C.B.

1961-11-21T23:59:59.000Z

243

NEUTRON SOURCES  

DOE Patents (OSTI)

A neutron source is obtained without employing any separate beryllia receptacle, as was formerly required. The new method is safer and faster, and affords a source with both improved yield and symmetry of neutron emission. A Be container is used to hold and react with Pu. This container has a thin isolating layer that does not obstruct the desired Pu--Be reaction and obviates procedures previously employed to disassemble and remove a beryllia receptacle. (AEC)

Richmond, J.L.; Wells, C.E.

1963-01-15T23:59:59.000Z

244

Neutron range spectrometer  

DOE Patents (OSTI)

A neutron range spectrometer and method for determining the neutron energy spectrum of a neutron emitting source are disclosed. Neutrons from the source are colliminated along a collimation axis and a position sensitive neutron counter is disposed in the path of the collimated neutron beam. The counter determines positions along the collimation axis of interactions between the neutrons in the neutron beam and a neutron-absorbing material in the counter. From the interaction positions, a computer analyzes the data and determines the neutron energy spectrum of the neutron beam. The counter is preferably shielded and a suitable neutron-absorbing material is He-3. 1 fig.

Manglos, S.H.

1988-03-10T23:59:59.000Z

245

ORNL Neutron Sciences  

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

ORNL's Neutron Science Future: Integrating Neutron Scattering Across the Laboratory Greg Smith, HFIR Center for Neutron Scattering Upgrade Status and Scientific Opportunities...

246

NEUTRONIC REACTOR  

DOE Patents (OSTI)

A nuclear reactor for isotope production is described. This reactor is designed to provide a maximum thermal neutron flux in a region adjacent to the periphery of the reactor rather than in the center of the reactor. The core of the reactor is generally centrally located with respect tn a surrounding first reflector, constructed of beryllium. The beryllium reflector is surrounded by a second reflector, constructed of graphite, which, in tune, is surrounded by a conventional thermal shield. Water is circulated through the core and the reflector and functions both as a moderator and a coolant. In order to produce a greatsr maximum thermal neutron flux adjacent to the periphery of the reactor rather than in the core, the reactor is designed so tbat the ratio of neutron scattering cross section to neutron absorption cross section averaged over all of the materials in the reflector is approximately twice the ratio of neutron scattering cross section to neutron absorption cross section averaged over all of the material of the core of the reactor.

Wigner, E.P.

1958-04-22T23:59:59.000Z

247

Boundary diffraction wave integrals for diffraction modeling of external occulters  

E-Print Network (OSTI)

An occulter is a large diffracting screen which may be flown in conjunction with a telescope to image extrasolar planets. The edge is shaped to minimize the diffracted light in a region beyond the occulter, and a telescope may be placed in this dark shadow to view an extrasolar system with the starlight removed. Errors in position, orientation, and shape of the occulter will diffract additional light into this region, and a challenge of modeling an occulter system is to accurately and quickly model these effects. We present a fast method for the calculation of electric fields following an occulter, based on the concept of the boundary diffraction wave: the 2D structure of the occulter is reduced to a 1D edge integral which directly incorporates the occulter shape, and which can be easily adjusted to include changes in occulter position and shape, as well as the effects of sources---such as exoplanets---which arrive off-axis to the occulter. The structure of a typical implementation of the algorithm is include...

Cady, E

2012-01-01T23:59:59.000Z

248

Diffraction encoded position measuring apparatus  

DOE Patents (OSTI)

When a lightwave passes through a transmission grating, diffracted beams appear at the output or opposite side of the grating that are effectively Doppler shifted in frequency (phase) whereby a detector system can compare the phase of the zero order and higher order beams to obtain an indication of position. Multiple passes through the grating increase resolution for a given wavelength of a laser signal. The resolution can be improved further by using a smaller wavelength laser to generate the grating itself. Since the grating must only have a pitch sufficient to produce diffracted orders, inexpensive, ultraviolet wavelength lasers can be utilized and still obtain high resolution detection. 3 figures.

Tansey, R.J.

1991-09-24T23:59:59.000Z

249

Structural Studies of Al:ZnO Powders and Thin Films | Stanford Synchrotron  

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

Structural Studies of Al:ZnO Powders and Thin Films Structural Studies of Al:ZnO Powders and Thin Films Monday, June 18, 2012 - 2:00pm SSRL Main Conference Room 137-322 Dr. Bridget Ingham, Associate Investigator, MacDiarmid Institute for Advanced Materials & Nanotechnology Al-doped ZnO (Al:ZnO) is a promising transparent conducting oxide. We have used complementary synchrotron and laboratory techniques to study the incorporation of Al within the ZnO lattice, and measure its effect on the crystallinity of thin films prepared by sol-gel techniques, with an aim to understand how these properties affect the film conductivity. I will present recent results from Al:ZnO powders and thin films, prepared with varying Al concentrations and calcination temperatures. Solid state 27Al NMR and ex situ X-ray diffraction (XRD) were performed on Al:ZnO

250

Thixoforming of Stellite Powder Compacts  

SciTech Connect

Thixoforming involves processing metallic alloys in the semi-solid state. The process requires the microstructure to be spheroidal when part-solid and part-liquid i.e. to consist of solid spheroids surrounded by liquid. The aim of this work was to investigate whether powder compacts can be used as feedstock for thixoforming and whether the consolidating pressure in the thixoformer can be used to remove porosity from the compact. The powder compacts were made from stellite 6 and stellite 21 alloys, cobalt-based alloys widely used for e.g. manufacturing prostheses. Isothermal heat treatments of small samples in the consolidated state showed the optimum thixoforming temperature to be in the range 1340 deg. C-1350 deg. C for both materials. The alloys were thixoformed into graphite dies and flowed easily to fill the die. Porosity in the thixoformed components was lower than in the starting material. Hardness values at various positions along the radius of the thixoformed demonstrator component were above the specification for both alloys.

Hogg, S. C. [Institute of PolymerTechnology and Materials Engineering, Loughborough University, Loughborough, LE11 3TU (United Kingdom); Atkinson, H. V. [Department of Engineering, University of Leicester, University Rd., Leicester LE1 7RH (United Kingdom); Kapranos, P. [Department of Engineering Materials, University of Sheffield, Mappin Street, Sheffield S1 3JD (United Kingdom)

2007-04-07T23:59:59.000Z

251

Process for the synthesis of iron powder  

DOE Patents (OSTI)

A process for preparing iron powder suitable for use in preparing the iron-potassium perchlorate heat-powder fuel mixture used in thermal batteries, comprises preparing a homogeneous, dense iron oxide hydroxide precipitate by homogeneous precipitation from an aqueous mixture of a ferric salt, formic or sulfuric acid, ammonium hydroxide and urea as precipitating agent; and then reducing the dense iron oxide hydroxide by treatment with hydrogen to prepare the iron powder. 2 figs.

Welbon, W.W.

1983-11-08T23:59:59.000Z

252

Process for the synthesis of iron powder  

DOE Patents (OSTI)

A process for preparing iron powder suitable for use in preparing the iron-potassium perchlorate heat-powder fuel mixture used in thermal batteries, comprises preparing a homogeneous, dense iron oxide hydroxide precipitate by homogeneous precipitation from an aqueous mixture of a ferric salt, formic or sulfuric acid, ammonium hydroxide and urea as precipitating agent; and then reducing the dense iron oxide hydroxide by treatment with hydrogen to prepare the iron powder.

Not Available

1982-03-06T23:59:59.000Z

253

Process for the synthesis of iron powder  

DOE Patents (OSTI)

A process for preparing iron powder suitable for use in preparing the iron-potassium perchlorate heat-powder fuel mixture used in thermal batteries, comprises preparing a homogeneous, dense iron oxide hydroxide precipitate by homogeneous precipitation from an aqueous mixture of a ferric salt, formic or sulfuric acid, ammonium hydroxide and urea as precipitating agent; and then reducing the dense iron oxide hydroxide by treatment with hydrogen to prepare the iron powder.

Welbon, William W. (Belleair, FL)

1983-01-01T23:59:59.000Z

254

The Production and Processing of Titanium Powder  

Science Conference Proceedings (OSTI)

Mar 6, 2013 ... Cost Affordable Titanium IV: The Production and Processing of Titanium Powder Sponsored by: TMS Structural Materials Division, TMS:...

255

Ultrafine hydrogen storage powders - Energy Innovation Portal  

A method of making hydrogen storage powder resistant to fracture in service involves forming a melt having the appropriate composition for the hydrogen storage ...

256

POWDERED AEROSOLS PERFORHANCE IN VARIOUS FIRE ...  

Science Conference Proceedings (OSTI)

... introduced into the car-parking tower without the ... In order to design an effective powdered ... rate of combustion), atmospheric (wind airflow) conditions ...

2011-11-01T23:59:59.000Z

257

Laboratory Evaluation of Bicarbonate Powders as Fire ...  

Science Conference Proceedings (OSTI)

... For the high strain case, the amount of powder required to extinguish the !lame was so small that the particle delivery was difficult to accurately ...

2012-10-21T23:59:59.000Z

258

Process for synthesizing compounds from elemental powders  

DOE Patents (OSTI)

A process for synthesizing intermetallic compounds from elemental powders. The elemental powders are initially combined in ratio a which approximates the stoichiometric composition of the intermetallic compound. The mixed powders are then formed into a compact which is heat treated at a controlled rate of heating such that an exothermic reaction between the elements is initiated. The heat treatment may be performed under controlled conditions ranging from a vacuum (pressureless sintering) to compression (hot pressing) to produce a desired densification of the intermetallic compound. In a preferred form of the invention, elemental powders of Fe and Al are combined to form aluminide compounds of Fe{sub 3}Al and FeAl.

Rabin, B.H.; Wright, R.N.

1990-01-01T23:59:59.000Z

259

PDF PRIMER: Powder Metallurgy and Superalloys - TMS  

Science Conference Proceedings (OSTI)

Feb 15, 2007 ... The very highly alloyed superalloys cannot be produced by conventional means. Powder metallurgy methods are needed to obtain...

260

COURSE NOTES: Powder Metallurgy: Materials, Processes ... - TMS  

Science Conference Proceedings (OSTI)

Feb 10, 2007 ... A complete course on powder metallurgy is offered for sale on CD-ROM. This course is targeted at students and engineers and includes...

Note: This page contains sample records for the topic "neutron powder diffraction" 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

Powder Injection Molding - Available Technologies - PNNL  

Summary. Presented here is a novel and innovative means of powder injection molding (PIM) of reactive refractory metals, such as titanium and its ...

262

Powder Panels for Dry Bay Fire Protection  

Science Conference Proceedings (OSTI)

... powder panel by a rotor blade resulted in ... by one of the vehicle manufacturers for the ... specific requirement is proprietary to the manufacturer, but will ...

2011-10-20T23:59:59.000Z

263

Neutron Repulsion  

E-Print Network (OSTI)

Earth is connected gravitationally, magnetically and electrically to its heat source - a neutron star that is obscured from view by waste products in the photosphere. Neutron repulsion is like the hot filament in an incandescent light bulb. Excited neutrons are emitted from the solar core and decay into hydrogen that glows in the photosphere like a frosted light bulb. Neutron repulsion was recognized in nuclear rest mass data in 2000 as the overlooked source of energy, the keystone of an arch that locked together these puzzling space-age observations: 1.) Excess 136Xe accompanied primordial helium in the stellar debris that formed the solar system (Fig. 1); 2.) The Sun formed on the supernova core (Fig. 2); 3.) Waste products from the core pass through an iron-rich mantle, selectively carrying lighter elements and lighter isotopes of each element into the photosphere (Figs. 3-4); and 4.) Neutron repulsion powers the Sun and sustains life (Figs. 5-7). Together these findings offer a framework for understanding how: a.) The Sun generates and releases neutrinos, energy and solar-wind hydrogen and helium; b.) An inhabitable planet formed and life evolved around an ordinary-looking star; c.) Continuous climate change - induced by cyclic changes in gravitational interactions of the Sun's energetic core with planets - has favored survival by adaptation.

Oliver K. Manuel

2011-02-08T23:59:59.000Z

264

Californium Neutron Irradiation Facility  

Science Conference Proceedings (OSTI)

Californium Neutron Irradiation Facility. Summary: ... Cf irradiation facility (Photograph by: Neutron Physics Group). Lead Organizational Unit: pml. Staff: ...

2013-07-23T23:59:59.000Z

265

Neutron Physics Group  

Science Conference Proceedings (OSTI)

... spectrum and fluencies is essential for several ... Neutron Interferometer and Optics Facility performed a ... other neutron scattering facilities depends on ...

2011-10-24T23:59:59.000Z

266

Powdered coal air dispersion nozzle  

SciTech Connect

An improved coal/air dispersion nozzle introduces fuel into the combustion chamber of a gas turbine engine as a finely atomized, dispersed spray for a uniform combustion. The nozzle has an inlet that receives finely powdered coal from a coal transport or coal/air fluidizer system and a scroll swirl generator is included within the nozzle to swirl a fluidized coal/air mixture supplied to the inlet of the nozzle. The scroll is in the form of a thin, flat metal sheet insert, twisted along its length, and configured to prevent build-up of coal particles within the nozzle prior to ejection from its outlet. Airblast air jets are included along the length of the nozzle body to assist in the discharge of the fluidized coal from the nozzle outlet and an angular pintle tip overlies the outlet to redirect coal/air mixture through a desired fluidized coal spray angle.

Kosek, T.P.; Steinhilper, E.A.

1981-10-27T23:59:59.000Z

267

Cold Neutron and Ultracold Neutron Sources  

Science Conference Proceedings (OSTI)

... Moderators Solid Methane CH 4 CD 4 ... In a cold neutron flux with a continuous spectrum, more neutrons could ... Magneto-vibrational Scatt. + ...

2009-07-13T23:59:59.000Z

268

Chapter 13 - NEUTRON AREA DETECTORS 1. NEUTRON ...  

Science Conference Proceedings (OSTI)

... The neutron peak corresponds to both reaction products being entirely absorbed in the ... 6. A fission chamber is a very low efficiency neutron detector ...

2009-11-29T23:59:59.000Z

269

NEUTRONIC REACTOR  

DOE Patents (OSTI)

A nuclear reactor which uses uranium in the form of elongated tubes as fuel elements and liquid as a coolant is described. Elongated tubular uranium bodies are vertically disposed in an efficient neutron slowing agent, such as graphite, for example, to form a lattice structure which is disposed between upper and lower coolant tanks. Fluid coolant tubes extend through the uranium bodies and communicate with the upper and lower tanks and serve to convey the coolant through the uranium body. The reactor is also provided with means for circulating the cooling fluid through the coolant tanks and coolant tubes, suitable neutron and gnmma ray shields, and control means.

Wigner, E.P.; Weinberg, A.W.; Young, G.J.

1958-04-15T23:59:59.000Z

270

Powder River 0 20 40 KILOMETERS  

E-Print Network (OSTI)

1 Monitoring Coal Bed Methane Production: A Case Study from the Powder River Basin, Wyoming, United The growing significance of the Powder River Basin's Coal Bed Methane (CBM) to United States domestic energy% of gas mostly methane, hence the name Coal Bed Methane (CBM). The types of coal, in increasing order

271

Wet powder seal for gas containment  

DOE Patents (OSTI)

A gas seal is formed by a compact layer of an insoluble powder and liquid filling the fine interstices of that layer. The smaller the particle size of the selected powder, such as sand or talc, the finer will be the interstices or capillary spaces in the layer and the greater will be the resulting sealing capacity, i.e., the gas pressure differential which the wet powder layer can withstand. Such wet powder seal is useful in constructing underground gas reservoirs or storage cavities for nuclear wastes as well as stopping leaks in gas mains buried under ground or situated under water. The sealing capacity of the wet powder seal can be augmented by the hydrostatic head of a liquid body established over the seal.

Stang, L.G.

1979-08-29T23:59:59.000Z

272

Wet powder seal for gas containment  

DOE Patents (OSTI)

A gas seal is formed by a compact layer of an insoluble powder and liquid filling the fine interstices of that layer. The smaller the particle size of the selected powder, such as sand or talc, the finer will be the interstices or capillary spaces in the layer and the greater will be the resulting sealing capacity, i.e., the gas pressure differential which the wet powder layer can withstand. Such wet powder seal is useful in constructing underground gas reservoirs or storage cavities for nuclear wastes as well as stopping leaks in gas mains buried under ground or situated under water. The sealing capacity of the wet powder seal can be augmented by the hydrostatic head of a liquid body established over the seal.

Stang, Louis G. (Sayville, NY)

1982-01-01T23:59:59.000Z

273

NEUTRONIC REACTORS  

DOE Patents (OSTI)

The design of control rods for nuclear reactors are described. In this design the control rod consists essentially of an elongated member constructed in part of a neutron absorbing material and having tube means extending therethrough for conducting a liquid to cool the rod when in use.

Anderson, H.L.

1958-10-01T23:59:59.000Z

274

Methods for absorbing neutrons  

DOE Patents (OSTI)

A conduction cooled neutron absorber may include a metal matrix composite that comprises a metal having a thermal neutron cross-section of at least about 50 barns and a metal having a thermal conductivity of at least about 1 W/cmK. Apparatus for providing a neutron flux having a high fast-to-thermal neutron ratio may include a source of neutrons that produces fast neutrons and thermal neutrons. A neutron absorber positioned adjacent the neutron source absorbs at least some of the thermal neutrons so that a region adjacent the neutron absorber has a fast-to-thermal neutron ratio of at least about 15. A coolant in thermal contact with the neutron absorber removes heat from the neutron absorber.

Guillen, Donna P. (Idaho Falls, ID); Longhurst, Glen R. (Idaho Falls, ID); Porter, Douglas L. (Idaho Falls, ID); Parry, James R. (Idaho Falls, ID)

2012-07-24T23:59:59.000Z

275

Neutron reflecting supermirror structure  

DOE Patents (OSTI)

An improved neutron reflecting supermirror structure comprising a plurality of stacked sets of bilayers of neutron reflecting materials. The improved neutron reflecting supermirror structure is adapted to provide extremely good performance at high incidence angles, i.e. up to four time the critical angle of standard neutron mirror structures. The reflection of neutrons striking the supermirror structure at a high critical angle provides enhanced neutron throughput, and hence more efficient and economical use of neutron sources.

Wood, James L. (Drayton Plains, MI)

1992-01-01T23:59:59.000Z

276

Neutron reflecting supermirror structure  

DOE Patents (OSTI)

An improved neutron reflecting supermirror structure comprising a plurality of stacked sets of bilayers of neutron reflecting materials. The improved neutron reflecting supermirror structure is adapted to provide extremely good performance at high incidence angles, i.e. up to four time the critical angle of standard neutron mirror structures. The reflection of neutrons striking the supermirror structure at a high critical angle provides enhanced neutron throughput, and hence more efficient and economical use of neutron sources. 2 figs.

Wood, J.L.

1992-12-01T23:59:59.000Z

277

SNS Instrument System Beam Lines | ORNL Neutron Sciences  

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

SNS Instrument Beam Lines SNS Instrument Beam Lines This diagram shows the beam lines designated for currently funded instruments. Clicking on an instrument description will take you to the page for that instrument. Clicking anywhere else on the image will open a full-size, printable PDF file. SNS Instrument Layout Backscattering Spectrometer (BASIS) Disordered Materials Diffractometer (NOMAD) Wide Angular-Range Chopper Spectrometer (ARCS) Fine-Resolution Fermi Chopper Spectrometer (SEQUOIA) Coming Soon - Vibrational Spectrometer (VISION) Neutron Spin Echo (NSE) Hybrid Spectrometer (HYSPEC) Fundamental Neutron Physics Beamline (FNPB) Single Crystal Diffractometer (TOPAZ) Versatile Neutron Imaging Instrument (VENUS) Macromolecular Diffractometer (MaNDi) Powder Diffractometer (POWGEN3) Engineering Diffractometer (VULCAN) Extended Q-Range Small Angle Neutron Diffractometer (EQ-SANS) Cold Neutron Chopper Spectrometer (CNCS) Liquids (horizontal surface) Reflectometer (LR) Magnetic Advanced Grazing InCidence Spectrometer (MAGICS) High Pressure Diffractometer (SNAP) Coming Soon - Elastic Diffuse Scattering Spectrometer (CORELLI)

278

Structural Evolution in Mechanically Alloyed Al-Fe Powder Mixtures  

Science Conference Proceedings (OSTI)

[4,5] Mechanical alloying is a solid-state powder processing technique which involves repeated welding, fracturing and rewelding of powder particles in a dry, ...

279

Simulation of Powder Compact Forging Process for Producing a ...  

Science Conference Proceedings (OSTI)

Presentation Title, Simulation of Powder Compact Forging Process for Producing a ... Powder compact forging is a recently developed manufacturing process to...

280

Investigation of Powder Metallurgy Titanium Matrix Composites by ...  

Science Conference Proceedings (OSTI)

Presentation Title, Investigation of Powder Metallurgy Titanium Matrix Composites by Planetary Ball-milling of Ti Powder Dispersed with Vapour Grown Carbon...

Note: This page contains sample records for the topic "neutron powder diffraction" 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

Fabrication of Nanostructural Aluminum Alloy Powder with Ball ...  

Science Conference Proceedings (OSTI)

The aim of this paper is to fabricate aluminum alloy powder with nanostructure using ball milling method. The commercial Al-Mg-Cu alloy powder was milled...

282

New Atomization Technology for Fine Amorphous Alloy Powder ...  

Science Conference Proceedings (OSTI)

However, the present conventional powder-making processes (gas and water atomization) seem difficult to reduce the price of amorphous alloy powders.

283

Diffraction and central exclusive production at ATLAS  

Science Conference Proceedings (OSTI)

The diffractive physics program for the ATLAS experiment with an emphasis on the central exclusive production is discussed. The key point in this discussion is the need for an unambiguous experimental definition of diffractive signature which would be acceptable and reproducible by theorists. Recent ATLAS results from samples enhanced in diffraction contribution underline this need.

Marek Taevsk; The ATLAS collaboration

2011-01-01T23:59:59.000Z

284

Neutron Scattering Facilities 1982  

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

NEUTRON SOURCES NEUTRON SOURCES Types of Sources U.S. Sources Available for Users Plans for the Future The Neutron Scattering Society of America (NSSA) SNS/ANL School on Neutron and x-Ray Scattering, June 2011 Jim Rhyne Lujan Neutron Scattering Center Los Alamos National Lab. What do we need to do neutron scattering? * Neutron Source - produces neutrons * Diffractometer or Spectrometer - Allows neutrons to interact with sample - Sorts out discrete wavelengths by monochromator (reactor) or by time of flight (pulse source) - Detectors pick up neutrons scattered from sample * Analysis methods to determine material properties * Brain power to interpret results Sources of neutrons for scattering * Nuclear Reactor - Neutrons produced from fission of 235 U - Fission spectrum neutrons

285

Continuous blending of dry pharmaceutical powders  

E-Print Network (OSTI)

Conventional batch blending of pharmaceutical powders coupled with long quality analysis times increases the production cycle time leading to strained cash flows. Also, scale-up issues faced in process development causes ...

Pernenkil, Lakshman

2008-01-01T23:59:59.000Z

286

Biaxially textured articles formed by powder metallurgy  

DOE Patents (OSTI)

A biaxially textured alloy article comprises Ni powder and at least one powder selected from the group consisting of Cr, W, V, Mo, Cu, Al, Ce, YSZ, Y, Rare Earths, (RE), MgO, CeO.sub.2, and Y.sub.2 O.sub.3 ; compacted and heat treated, then rapidly recrystallized to produce a biaxial texture on the article. In some embodiments the alloy article further comprises electromagnetic or electro-optical devices and possesses superconducting properties.

Goyal, Amit (Knoxville, TN); Williams, Robert K. (Knoxville, TN)

2001-01-01T23:59:59.000Z

287

Contact ORNL Neutron Sciences  

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

Sciences Organization Charts Neutron Sciences Directorate Associate Laboratory Director for Neutron Sciences, Kelly Beierschmitt Biology and Soft Matter Division Director, Paul...

288

NEUTRON SOURCE  

DOE Patents (OSTI)

A neutron source of the antimony--beryllium type is presented. The source is comprised of a solid mass of beryllium having a cylindrical recess extending therein and a cylinder containing antimony-124 slidably disposed within the cylindrical recess. The antimony cylinder is encased in aluminum. A berylliunn plug is removably inserted in the open end of the cylindrical recess to completely enclose the antimony cylinder in bsryllium. The plug and antimony cylinder are each provided with a stud on their upper ends to facilitate handling remotely.

Reardon, W.A.; Lennox, D.H.; Nobles, R.G.

1959-01-13T23:59:59.000Z

289

Energy Dispersive Synchrotron Diffraction for In-situ Analyses of ...  

Science Conference Proceedings (OSTI)

Symposium, O. Advanced Neutron and Synchrotron Studies of Materials .... Status of China Spallation Neutron Source and Perspectives of Neutron Research in...

290

Spallation Neutron Source | ORNL Neutron Sciences  

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

Spallation Neutron Source SNS site, Spring 2012 The 80-acre SNS site is located on the east end of the ORNL campus and is about a three-minute drive from her sister neutron...

291

A brief History of Neutron Scattering at the Oak Ridge High Flux Isotope Reactor  

Science Conference Proceedings (OSTI)

Neutron scattering at the Oak Ridge National Laboratory dates back to 1945 when Ernest Wollan installed a modified x-ray diffractometer on a beam port of the original graphite reactor. Subsequently, Wollan and Clifford Shull pioneered neutron diffraction and laid the foundation for an active neutron scattering effort that continued through the 1950s, using the Oak Ridge Research reactor after 1958, and, starting in 1966, the High Flux Isotope Reactor, or HFIR.

Nagler, Stephen E [ORNL; Mook Jr, Herbert A [ORNL

2008-01-01T23:59:59.000Z

292

Dr. Michael Agamalian | ORNL Neutron Sciences  

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

Dr. Michael Agamalian Dr. Michael Agamalian Lead Scientist, Ultra-Small-Angle Neutron Scattering (USANS), SNS Education PhD in Physics, St. Petersburg Nuclear Physics Institute, Russia Description of Research Michael Agamalian and collaborators have made important contributions to the development of the ORNL Bonse-Hart Ultra-Small-Angle Neutron Scattering instrument (USANS). In particular, they adopted the classical X-ray Bonse-Hart technique for neutrons by modifying the Si channel-cut crystal and introducing an additional element, a Cd absorber. This innovation, combined with application of a specialized chemical-mechanical treatment of the diffractive surfaces of the Si channel-cut crystal, has increased the sensitivity of the ORNL USANS instrument by three orders of magnitude. This

293

Chemical and Engineering Materials | Neutron Science | ORNL  

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

Chemical and Engineering Materials Chemical and Engineering Materials SHARE Chemical and Engineering Materials Neutron-based research at SNS and HFIR in Chemical and Engineering Materials strives to understand the structure and dynamics of chemical systems and novel engineering materials. The user community takes advantage of capabilities of neutron scattering for measurements over wide ranges of experimental and operating conditions, including studies of chemical and physical changes in situ. User experiments with diffraction, small-angle scattering, inelastic and quasi-elastic scattering, and neutron imaging instruments address a range of problems in chemistry and in engineering materials research. Current areas of research supported within Chemical and Engineering Materials include: The structure and dynamics of electrical energy storage materials

294

Slip casting nano-particle powders for making transparent ceramics  

DOE Patents (OSTI)

A method of making a transparent ceramic including the steps of providing nano-ceramic powders in a processed or unprocessed form, mixing the powders with de-ionized water, the step of mixing the powders with de-ionized water producing a slurry, sonifing the slurry to completely wet the powder and suspend the powder in the de-ionized water, separating very fine particles from the slurry, molding the slurry, and curing the slurry to produce the transparent ceramic.

Kuntz, Joshua D. (Livermore, CA); Soules, Thomas F. (Livermore, CA); Landingham, Richard Lee (Livermore, CA); Hollingsworth, Joel P. (Oakland, CA)

2011-04-12T23:59:59.000Z

295

Nano-crystalline powders and suspensions generated using a flow-through hydrothermal process, Part 1: Characterization  

SciTech Connect

A wide range of ultra-fine, nano-crystalline powders and suspensions have been produced using Rapid Thermal Decomposition of precursors in Solution (RTDS). These materials include single and multi-component iron-, 11 zirconium-, titanium-, nickel-, and chromium-oxide/oxyhydroxide powders. RTDS is a flow-through hydrothermal process capable of producing nano-crystalline particulate material at rates of up to 100 grams of solid per hour. We present the results of characterization efforts on RTDS iron oxyhydroxide and zirconium oxide systems. As-collected RTDS suspensions were characterized using optical light scattering. Separated RTDS powders were evaluated using X-ray diffraction, electron microscopy, gas adsorption analysis, thermal gravimetric analysis, and chemical analysis.

Darab, J.G.; Buehler, M.F.; Linehan, J.C.; Matson, D.W.

1994-04-01T23:59:59.000Z

296

High precision thermal neutron detectors  

Science Conference Proceedings (OSTI)

Two-dimensional position sensitive detectors are indispensable in neutron diffraction experiments for determination of molecular and crystal structures in biology, solid-state physics and polymer chemistry. Some performance characteristics of these detectors are elementary and obvious, such as the position resolution, number of resolution elements, neutron detection efficiency, counting rate and sensitivity to gamma-ray background. High performance detectors are distinguished by more subtle characteristics such as the stability of the response (efficiency) versus position, stability of the recorded neutron positions, dynamic range, blooming or halo effects. While relatively few of them are needed around the world, these high performance devices are sophisticated and fairly complex; their development requires very specialized efforts. In this context, we describe here a program of detector development, based on {sup 3}He filled proportional chambers, which has been underway for some years at Brookhaven. Fundamental approaches and practical considerations are outlined that have resulted in a series of high performance detectors with the best known position resolution, position stability, uniformity of reliability over time of this type.

Radeka, V.; Schaknowski, N.A.; Smith, G.C.; and Yu, B.

1994-10-01T23:59:59.000Z

297

Dynamic compaction of tungsten carbide powder.  

Science Conference Proceedings (OSTI)

The shock compaction behavior of a tungsten carbide powder was investigated using a new experimental design for gas-gun experiments. This design allows the Hugoniot properties to be measured with reasonably good accuracy despite the inherent difficulties involved with distended powders. The experiments also provide the first reshock state for the compacted powder. Experiments were conducted at impact velocities of 245, 500, and 711 m/s. A steady shock wave was observed for some of the sample thicknesses, but the remainder were attenuated due to release from the back of the impactor or the edge of the sample. The shock velocity for the powder was found to be quite low, and the propagating shock waves were seen to be very dispersive. The Hugoniot density for the 711 m/s experiment was close to ambient crystal density for tungsten carbide, indicating nearly complete compaction. When compared with quasi-static compaction results for the same material, the dynamic compaction data is seen to be significantly stiffer for the regime over which they overlap. Based on these initial results, recommendations are made for improving the experimental technique and for future work to improve our understanding of powder compaction.

Gluth, Jeffrey Weston; Hall, Clint Allen; Vogler, Tracy John; Grady, Dennis Edward

2005-04-01T23:59:59.000Z

298

Die-target for dynamic powder consolidation  

DOE Patents (OSTI)

A die/target is disclosed for consolidation of a powder, especially an atomized rapidly solidified metal powder, to produce monoliths by the dynamic action of a shock wave, especially a shock wave produced by the detonation of an explosive charge. The die/target comprises a rectangular metal block having a square primary surface with four rectangular mold cavities formed therein to receive the powder. The cavities are located away from the geometrical center of the primary surface and are distributed around such center while also being located away from the geometrical diagonals of the primary surface to reduce the action of reflected waves so as to avoid tensile cracking of the monoliths. The primary surface is covered by a powder retention plate which is engaged by a flyer plate to transmit the shock wave to the primary surface and the powder. Spawl plates are adhesively mounted on other surfaces of the block to act as momentum traps so as to reduce reflected waves in the block. 4 figs.

Flinn, J.E.; Korth, G.E.

1985-06-27T23:59:59.000Z

299

Diffraction gratings used as identifying markers  

DOE Patents (OSTI)

A finely detailed diffraction grating is applied to an object as an identifier or tag which is unambiguous, difficult to duplicate, or remove and transfer to another item, and can be read and compared with prior readings with relative ease. The exact pattern of the diffraction grating is mapped by diffraction moire techniques and recorded for comparison with future readings of the same grating. 7 figures.

Deason, V.A.; Ward, M.B.

1991-03-26T23:59:59.000Z

300

Twenty years of diffraction at the Tevatron  

SciTech Connect

Results on diffractive particle interactions from the Fermilab Tevatron {bar p}p collider are placed in perspective through a QCD inspired phenomenological approach, which exploits scaling and factorization properties observed in data. The results discussed are those obtained by the CDF Collaboration from a comprehensive set of single, double, and multigap soft and hard diffraction processes studied during the twenty year period since 1985, when the CDF diffractive program was proposed and the first Blois Workshop was held.

Goulianos, K.; /Rockefeller U.

2005-10-01T23:59:59.000Z

Note: This page contains sample records for the topic "neutron powder diffraction" 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

ORNL neutron facilities deliver neutrons  

Science Conference Proceedings (OSTI)

The High Flux Isotope Reactor (HFIR) at Oak Ridge National Laboratory (ORNL) resumed full power operations on May 16, 2007. There were three experiment cycles of 23 to 25 days in FY2007 and another six are proposed for FY2008 beginning in November 2007. During FY 2007, the High Flux Isotope Reactor delivered 1178 operating hours to users. Commissioning of two SANS instruments is under way and these instruments will join the user program in 2008. The Neutron Scattering Science Advisory Committee endorsed language encouraging development of the science case for two instruments proposed for HFIR.

Ekkebus, Allen E [ORNL

2008-01-01T23:59:59.000Z

302

Available Technologies: Ultra-High Density Diffraction ...  

The researchers have demonstrated that an extremely high diffraction intensity ... www.lbl.gov/Tech-Transfer/licensing/index ... OF ENERGY OFFICE OF ...

303

Automated Transmission Kikuchi Diffraction for Nanomaterials ...  

Science Conference Proceedings (OSTI)

Presentation Title, Automated Transmission Kikuchi Diffraction for Nanomaterials Characterization in the SEM. Author(s), Scott Sitzman. On-Site Speaker...

304

Energy Density Functional for Nuclei and Neutron Stars  

Science Conference Proceedings (OSTI)

Background: Recent observational data on neutron star masses and radii provide stringent constraints on the equation of state of neutron rich matter [ Annu. Rev. Nucl. Part. Sci. 62 485 (2012)]. Purpose: We aim to develop a nuclear energy density functional that can be simultaneously applied to finite nuclei and neutron stars. Methods: We use the self-consistent nuclear density functional theory (DFT) with Skyrme energy density functionals and covariance analysis to assess correlations between observables for finite nuclei and neutron stars. In a first step two energy functionals a high density energy functional giving reasonable neutron properties, and a low density functional fitted to nuclear properties are matched. In a second step, we optimize a new functional using exactly the same protocol as in earlier studies pertaining to nuclei but now including neutron star data. This allows direct comparisons of performance of the new functional relative to the standard one. Results: The new functional TOV-min yields results for nuclear bulk properties (energy, rms radius, diffraction radius, and surface thickness) that are of the same quality as those obtained with the established Skyrme functionals, including SV-min. When comparing SV-min and TOV-min, isoscalar nuclear matter indicators vary slightly while isovector properties are changed considerably. We discuss neutron skins, dipole polarizability, separation energies of the heaviest elements, and proton and neutron drip lines. We confirm a correlation between the neutron skin of 208Pb and the neutron star radius. Conclusions: We demonstrate that standard energy density functionals optimized to nuclear data do not carry information on the expected maximum neutron star mass, and that predictions can only be made within an extremely broad uncertainty band. For atomic nuclei, the new functional TOV-min performs at least as well as the standard nuclear functionals, but it also reproduces expected neutron star data within assumed error bands. This functional is expected to yield more reliable predictions in the region of very neutron rich heavy nuclei.

Erler, J. [UTK/ORNL/German Cancer Research Center-Heidelberg; Horowitz, C. J. [UTK/ORNL/Indiana University; Nazarewicz, Witold [UTK/ORNL/University of Warsaw; Rafalski, M. [UTK/ORNL; Reinhard, P.-G. [Universitat Erlangen, Germany

2013-01-01T23:59:59.000Z

305

Atomization methods for forming magnet powders  

SciTech Connect

The invention encompasses methods of utilizing atomization, methods for forming magnet powders, methods for forming magnets, and methods for forming bonded magnets. The invention further encompasses methods for simulating atomization conditions. In one aspect, the invention includes an atomization method for forming a magnet powder comprising: a) forming a melt comprising R.sub.2.1 Q.sub.13.9 B.sub.1, Z and X, wherein R is a rare earth element; X is an element selected from the group consisting of carbon, nitrogen, oxygen and mixtures thereof; Q is an element selected from the group consisting of Fe, Co and mixtures thereof; and Z is an element selected from the group consisting of Ti, Zr, Hf and mixtures thereof; b) atomizing the melt to form generally spherical alloy powder granules having an internal structure comprising at least one of a substantially amorphous phase or a substantially nanocrystalline phase; and c) heat treating the alloy powder to increase an energy product of the alloy powder; after the heat treatment, the alloy powder comprising an energy product of at least 10 MGOe. In another aspect, the invention includes a magnet comprising R, Q, B, Z and X, wherein R is a rare earth element; X is an element selected from the group consisting of carbon, nitrogen, oxygen and mixtures thereof; Q is an element selected from the group consisting of Fe, Co and mixtures thereof; and Z is an element selected from the group consisting of Ti, Zr, Hf and mixtures thereof; the magnet comprising an internal structure comprising R.sub.2.1 Q.sub.13.9 B.sub.1.

Sellers, Charles H. (Idaho Falls, ID); Branagan, Daniel J. (Idaho Falls, ID); Hyde, Timothy A. (Idaho Falls, ID)

2000-01-01T23:59:59.000Z

306

Fast-neutron solid-state dosimeter  

DOE Patents (OSTI)

This patent relates to an improved fast-neutron solid-state dosimeter that does not require separation of materials before it can be read out, that utilizes materials that do not melt or otherwise degrade at about 300$sup 0$C readout temperature, that provides a more efficient dosimeter, and that can be reused. The dosimeters are fabricated by intimately mixing a TL material, such as CaSO$sub 4$:Dy, with a powdered polyphenyl, such as p-sexiphenyl, and hot- pressing the mixture to form pellets, followed by out-gassing in a vacuum furnace at 150$sup 0$C prior to first use dosimeters. (auth)

Kecker, K.H.; Haywood, F.F.; Perdue, P.T.; Thorngate, J.H.

1975-07-22T23:59:59.000Z

307

NEUTRONIC REACTORS  

DOE Patents (OSTI)

A method is presented for loading and unloading rod type fuel elements of a neutronic reactor of the heterogeneous, solld moderator, liquid cooled type. In the embodiment illustrated, the fuel rods are disposed in vertical coolant channels in the reactor core. The fuel rods are loaded and unloaded through the upper openings of the channels which are immersed in the coolant liquid, such as water. Unloading is accomplished by means of a coffer dam assembly having an outer sleeve which is placed in sealing relation around the upper opening. A radiation shield sleeve is disposed in and reciprocable through the coffer dam sleeve. A fuel rod engaging member operates through the axial bore in the radiation shield sleeve to withdraw the fuel rod from its position in the reactor coolant channel into the shield, the shield snd rod then being removed. Loading is accomplished in the reverse procedure.

Wigner, E.P.; Young, G.J.

1958-10-14T23:59:59.000Z

308

Neutron reflecting supermirror structure  

DOE Patents (OSTI)

An improved neutron reflecting supermirror structure comprising a plurality of stacked sets of bilayers of neutron reflecting materials. The improved neutron reflecting supermirror structure is adapted to provide extremely good performance at high incidence angles, i.e. up to four time the critical angle of standard neutron mirror structures. The reflection of neutrons striking the supermirror structure at a high critical angle provides enhanced neutron throughput, and hence more efficient and economical use of neutron sources. One layer of each set of bilayers consist of titanium, and the second layer of each set of bilayers consist of an alloy of nickel with carbon interstitially present in the nickel alloy.

Wood, James L. (Drayton Plains, MI)

1992-01-01T23:59:59.000Z

309

Dry powder mixes comprising phase change materials  

DOE Green Energy (OSTI)

A free flowing, conformable powder-like mix of silica particles and a phase change material (PCM) is provided. The silica particles have a critical size of about 0.005 to about 0.025 microns and the PCM must be added to the silica in an amount of 75% or less PCM per combined weight of silica and PCM. The powder-like mix can be used in tableware items, medical wraps, tree wraps, garments, quilts and blankets, and particularly in applications for heat protection for heat sensitive items, such as aircraft flight recorders, and for preventing brake fade in automobiles, buses, trucks and aircraft. 3 figs.

Salyer, I.O.

1995-12-26T23:59:59.000Z

310

ATOMIZATION METHOD OF MAKING URANIUM POWDER  

SciTech Connect

Atomized U powder was produced by forming an electric arc between two U electrodes in an inert atmosphere and sending a high velocity stream of inert gas through the arc. Uranium particles obtained by this method were of spherical shape; smaller particles contained mostly small grains, and larger particles wore characterizcd by larger grains. The particles were ductile and could be hotpressed to a compact of high density. The temporary equipment used for those preliminary tests on atomization was not adequate to control particle size. Suggestions for the production of atomized U powder of controllable quality are included. (arth)

Hausner, H.H.; Mansfield, H.

1950-08-01T23:59:59.000Z

311

Synthesis of ultrafine powders by microwave heating  

DOE Patents (OSTI)

A method of synthesizing ultrafine powders using microwaves is described. A water soluble material is dissolved in water and the resulting aqueous solution is exposed to microwaves until the water has dissolved. The resulting material is an ultrafine powder. This method can be used to make Al/sub 2/O/sub 3/, NiO /plus/ Al/sub 2/O/sub 3/ and NiO as well as a number of other materials including GaBa/sub 2/Cu/sub 3/O/sub x/. 1 tab.

Meek, T.T.; Sheinberg, H.; Blake, R.D.

1987-04-24T23:59:59.000Z

312

Dry powder mixes comprising phase change materials  

DOE Patents (OSTI)

A free flowing, conformable powder-like mix of silica particles and a phase change material (PCM) is provided. The silica particles have a critical size of about 0.005 to about 0.025 microns and the PCM must be added to the silica in an amount of 75% or less PCM per combined weight of silica and PCM. The powder-like mix can be used in tableware items, medical wraps, tree wraps, garments, quilts and blankets, and particularly in applications for heat protection for heat sensitive items, such as aircraft flight recorders, and for preventing brake fade in automobiles, buses, trucks and aircraft. 3 figures.

Salyer, I.O.

1994-12-06T23:59:59.000Z

313

Dry powder mixes comprising phase change materials  

DOE Patents (OSTI)

A free flowing, conformable powder-like mix of silica particles and a phase change material (PCM) is provided. The silica particles have a critical size of about 0.005 to about 0.025 microns and the PCM must be added to the silica in an amount of 75% or less PCM per combined weight of silica and PCM. The powder-like mix can be used in tableware items, medical wraps, tree wraps, garments, quilts and blankets, and particularly in applications for heat protection for heat sensitive items, such as aircraft flight recorders, and for preventing brake fade in automobiles, buses, trucks and aircraft.

Salyer, Ival O. (Dayton, OH)

1994-01-01T23:59:59.000Z

314

Dry powder mixes comprising phase change materials  

DOE Patents (OSTI)

A free flowing, conformable powder-like mix of silica particles and a phase change material (PCM) is provided. The silica particles have a critical size of about 0.005 to about 0.025 microns and the PCM must be added to the silica in an amount of 75% or less PCM per combined weight of silica and PCM. The powder-like mix can be used in tableware items, medical wraps, tree wraps, garments, quilts and blankets, and particularly in applications for heat protection for heat sensitive items, such as aircraft flight recorders, and for preventing brake fade in automobiles, buses, trucks and aircraft.

Salyer, Ival O. (Dayton, OH)

1995-01-01T23:59:59.000Z

315

Process for preparing active oxide powders  

DOE Patents (OSTI)

An improved process for preparing active oxide powders in which cation hydroxide gels, prepared in the conventional manner are chemically dried by alternately washing the gels with a liquid organic compound having polar characteristics and a liquid organic compound having nonpolar characteristics until the mechanical water is removed from the gel. The water-free cation hydroxide is then contacted with a final liquid organic wash to remove the previous organic wash and speed drying. The dried hydroxide treated in the conventional manner will form a highly sinterable active oxide powder.

Berard, Michael F. (Ames, IA); Hunter, Jr., Orville (Ames, IA); Shiers, Loren E. (Ames, IA); Dole, Stephen L. (Burnt Hills, NY); Scheidecker, Ralph W. (Ames, IA)

1979-02-20T23:59:59.000Z

316

The Versatile Neutron Imaging Instrument at SNS | ORNL Neutron...  

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

The Versatile Neutron Imaging Instrument at SNS VENUS: Neutron imaging to advance energy efficiency VENUS: Neutron imaging to advance energy efficiency. As its name indicates,...

317

Imaging with Scattered Neutrons  

E-Print Network (OSTI)

We describe a novel experimental technique for neutron imaging with scattered neutrons. These scattered neutrons are of interest for condensed matter physics, because they permit to reveal the local distribution of incoherent and coherent scattering within a sample. In contrast to standard attenuation based imaging, scattered neutron imaging distinguishes between the scattering cross section and the total attenuation cross section including absorption. First successful low-noise millimeter-resolution images by scattered neutron radiography and tomography are presented.

H. Ballhausen; H. Abele; R. Gaehler; M. Trapp; A. Van Overberghe

2006-10-30T23:59:59.000Z

318

Directorate Organization | ORNL Neutron Sciences  

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

ORNL Neutron Sciences Directorate The Neutron Sciences Directorate (NScD) manages and operates the Spallation Neutron Source and the High Flux Isotope Reactor, two of the world's...

319

Characterization of the carbides and the martensite phase in powder-metallurgy high-speed steel  

SciTech Connect

A microstructural characterization of the powder-metallurgy high-speed-steel S390 Microclean was performed based on an elemental distribution of the carbide phase as well as crystallographic analyses. The results showed that there were two types of carbides present: vanadium-rich carbides, which were not chemically homogeneous and exhibited a tungsten-enriched or tungsten-depleted central area; and chemically homogeneous tungsten-rich M{sub 6}C-type carbides. Despite the possibility of chemical inhomogenities, the crystallographic orientation of each of the carbides was shown to be uniform. Using electron backscatter diffraction the vanadium-rich carbides were determined to be either cubic VC or hexagonal V{sub 6}C{sub 5}, while the tungsten-rich carbides were M{sub 6}C. The electron backscatter diffraction results were also verified using X-ray diffraction. Several electron backscatter diffraction pattern maps were acquired in order to define the fraction of each carbide phase as well as the amount of martensite phase. The fraction of martensite was estimated using band-contrast images, while the fraction of carbides was calculated using the crystallographic data.

Godec, Matjaz, E-mail: matjaz.godec@imt.si [Institute of Metals and Technology, Lepi pot 11, 1000 Ljubljana (Slovenia); Batic, Barbara Setina; Mandrino, Djordje; Nagode, Ales; Leskovsek, Vojteh [Institute of Metals and Technology, Lepi pot 11, 1000 Ljubljana (Slovenia); Skapin, Sreco D. [Jozef Stefan Institute, Jamova 39, 1000 Ljubljana (Slovenia); Jenko, Monika [Institute of Metals and Technology, Lepi pot 11, 1000 Ljubljana (Slovenia)

2010-04-15T23:59:59.000Z

320

Critical Experiments that Simulated Damp MOX Powders - Do They Meet the Need?  

DOE Green Energy (OSTI)

The OECD Nuclear Energy Agency (NEA) Working Party on Nuclear Criticality Safety (WPNCS) identified the MOX fuel manufacturing process as an area in which there is a need for additional integral benchmark data. The specific need focused on damp MOX powders. The WPNCS was ultimately asked by the NEA Nuclear Science Committee (NSC) to provide the framework for the selection and performance of new experiments that fill the identified need. A set of criteria was established to enable uniform comparison of experimental proposals with generic MOX application data. Criteria were established for five general characteristics: (1) neutronic parameters, (2) type of experiments, (3) financial aspects, (4) schedule, and (5) other considerations. Proposals were judged most importantly on their ability to match the neutronic parameters of predetermined MOX applications. The neutronic parameters that formed the basis for comparison included core average values (not local values) for flux, fission and capture rate; detailed balance data (fission and capture) for the main isotopes (Actinides, H and O); sensitivity coefficients to important nuclear reactions (fission, capture, elastic and inelastic scatter, nu-bar, mu-bar) for all uranium and plutonium isotopes, hydrogen, and oxygen; sensitivity profiles to the main nuclear reactions for uranium and plutonium isotopes; energy of average lethargy causing fission; and the average fission group energy. The focus of this paper is on the definition of the need; the neutronics criteria established to assess which, if any, of three proposed MOX experimental programs best meet the need; and the actual assessment of the proposed experimental programs.

J. Blair Briggs; Dr. Ali Nouri; Dr. Claes Nordborg

2005-09-01T23:59:59.000Z

Note: This page contains sample records for the topic "neutron powder diffraction" 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

NEUTRONIC REACTOR  

DOE Patents (OSTI)

This patent relates to neutronic reactors of the heterogeneous water cooled type, and in particular to a fuel element charging and discharging means therefor. In the embodiment illustrated the reactor contains horizontal, parallel coolant tubes in which the fuel elements are disposed. A loading cart containing a magnzine for holding a plurality of fuel elements operates along the face of the reactor at the inlet ends of the coolant tubes. The loading cart is equipped with a ram device for feeding fuel elements from the magazine through the inlot ends of the coolant tubes. Operating along the face adjacent the discharge ends of the tubes there is provided another cart means adapted to receive irradiated fuel elements as they are forced out of the discharge ends of the coolant tubes by the incoming new fuel elements. This cart is equipped with a tank coataining a coolant, such as water, into which the fuel elements fall, and a hydraulically operated plunger to hold the end of the fuel element being discharged. This inveation provides an apparatus whereby the fuel elements may be loaded into the reactor, irradiated therein, and unloaded from the reactor without stopping the fiow of the coolant and without danger to the operating personnel.

Ohlinger, L.A.; Wigner, E.P.; Weinberg, A.M.; Young, G.J.

1958-09-01T23:59:59.000Z

322

Neutron Scattering Conferences  

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

8-12, 2013 International Workshop: Powder & Electron Crystallography Location Patras, Greece Contact Partha Pratim Das Email partha@upatras.gr URL http:crystallographypatras.wor...

323

Neutron streak camera  

DOE Patents (OSTI)

Apparatus for improved sensitivity and time resolution of a neutron measurement. The detector is provided with an electrode assembly having a neutron sensitive cathode which emits relatively low energy secondary electrons. The neutron sensitive cathode has a large surface area which provides increased sensitivity by intercepting a greater number of neutrons. The cathode is also curved to compensate for differences in transit time of the neutrons emanating from the point source. The slower speeds of the secondary electrons emitted from a certain portion of the cathode are matched to the transit times of the neutrons impinging thereupon.

Wang, C.L.

1981-05-14T23:59:59.000Z

324

Organic metal neutron detector  

DOE Patents (OSTI)

A device for detection of neutrons comprises: as an active neutron sensing element, a conductive organic polymer having an electrical conductivity and a cross-section for said neutrons whereby a detectable change in said conductivity is caused by impingement of said neutrons on the conductive organic polymer which is responsive to a property of said polymer which is altered by impingement of said neutrons on the polymer; and means for associating a change in said alterable property with the presence of neutrons at the location of said device.

Butler, M.A.; Ginley, D.S.

1984-11-21T23:59:59.000Z

325

Layered semiconductor neutron detectors  

SciTech Connect

Room temperature operating solid state hand held neutron detectors integrate one or more relatively thin layers of a high neutron interaction cross-section element or materials with semiconductor detectors. The high neutron interaction cross-section element (e.g., Gd, B or Li) or materials comprising at least one high neutron interaction cross-section element can be in the form of unstructured layers or micro- or nano-structured arrays. Such architecture provides high efficiency neutron detector devices by capturing substantially more carriers produced from high energy .alpha.-particles or .gamma.-photons generated by neutron interaction.

Mao, Samuel S; Perry, Dale L

2013-12-10T23:59:59.000Z

326

The Influence of Alloy Chemistry and Powder Production Methods ...  

Science Conference Proceedings (OSTI)

Advanced nickel-base superalloys for use in gas turbine engines are produced .... Powder was separated from the exiting gas flow via a cyclone. Once cooled, the powder was removed from the system. (exposing .... The full data are given in ...

327

MATERIALS FOR SPALLATION NEUTRON SOURCES: IV: Neutronics  

Science Conference Proceedings (OSTI)

The Department of Energy has initiated a pre-conceptual design study for the National Spallation Neutron Source (NSNS) and given preliminary approval for the...

328

and Submicron Oxide Powders for Optoelectronic and Renewable ...  

Science Conference Proceedings (OSTI)

Among various materials processes, Umicore develops technologies and manufactures various oxide powders for optoelectronic and renewable energy...

329

Powder Removal from Complex Structures Produced Using Electron ...  

Science Conference Proceedings (OSTI)

About this Abstract. Meeting, Materials Science & Technology 2011. Symposium, Additive Manufacturing of Metals. Presentation Title, Powder Removal from...

330

Low Cost Titanium Powder Development for Additive Manufacturing ...  

Science Conference Proceedings (OSTI)

About this Abstract. Meeting, 2013 TMS Annual Meeting & Exhibition. Symposium , Cost Affordable Titanium IV. Presentation Title, Low Cost Titanium Powder...

331

Development of a Simplified Powder Processing Method for ...  

Science Conference Proceedings (OSTI)

... dispersion strengthened ferritic stainless steel microstructure. Precursor ferritic stainless steel powders were oxidized in situ using a newly developed gas...

332

Powder-based Processes and Products for Advanced Applications  

Science Conference Proceedings (OSTI)

James W Sears, South Dakota School of Mines & Technology. Scope, Numerous powder materials technologies have been developed for metals, ceramics,...

333

NORMAL EMISSION PHOTOELECTRON DIFFRACTION STUDIES AT SSRL  

E-Print Network (OSTI)

DIFFRACTION STUDIES AT SSRL S. D. Kevan June 1980 TWO-WEEKDIFFRACTION STUDIES AT SSRL S.D. Kevan Materials andOur group has worked at SSRL using the normal emission

Kevan, S.D.

2013-01-01T23:59:59.000Z

334

Instruments | Neutron Science | ORNL  

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

NScD Careers NScD Careers Supporting Organizations Neutron Science Home | Science & Discovery | Neutron Science | Instruments SHARE Instruments at SNS and HFIR SNS Instrument Name HFIR Instrument Name 1B NOMAD - Nanoscale-Ordered Materials Diffractometer CG-1 Development Beam Line 2 BASIS - Backscattering Spectrometer CG-1D IMAGING - Neutron Imaging Prototype Facility 3 SNAP - Spallation Neutrons and Pressure Diffractometer CG-2 GP-SANS - General-Purpose Small-Angle Neutron Scattering Diffractometer 4A MR - Magnetism Reflectometer CG-3 Bio-SANS - Biological Small-Angle Neutron Scattering Instrument 4B LR - Liquids Reflectometer CG-4C CTAX - Cold Neutron Triple-Axis Spectrometer 5 CNCS - Cold Neutron Chopper Spectrometer HB-1 PTAX - Polarized Triple-Axis Spectrometer

335

Ultrafast neutron detector  

DOE Patents (OSTI)

A neutron detector of very high temporal resolution is described. It may be used to measure distributions of neutrons produced by fusion reactions that persist for times as short as about 50 picoseconds.

Wang, C.L.

1985-06-19T23:59:59.000Z

336

Procurement - ORNL Neutron Sciences  

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

for the acquisition of goods and services for neutron scattering operations at SNS and HFIR. If you're interested in conducting business with the Neutron Sciences Directorate or...

337

Facilities | ORNL Neutron Sciences  

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

Isotope Reactor. The pulsed neutron source at SNS and the continuous neutron source at HFIR complement each other well and, along with their state-of-the-art instruments, provide...

338

Pulsed-neutron monochromator  

DOE Patents (OSTI)

In one aspect, the invention is an improved pulsed-neutron monochromator of the vibrated-crystal type. The monochromator is designed to provide neutron pulses which are characterized both by short duration and high density. A row of neutron-reflecting crystals is disposed in a neutron beam to reflect neutrons onto a common target. The crystals in the row define progressively larger neutron-scattering angles and are vibrated sequentially in descending order with respect to the size of their scattering angles, thus generating neutron pulses which arrive simultaneously at the target. Transducers are coupled to one end of the crystals to vibrate them in an essentially non-resonant mode. The transducers propagate transverse waves in the crystal which progress longitudinally therein. The waves are absorbed at the undriven ends of the crystals by damping material mounted thereon. In another aspect, the invention is a method for generating neutron pulses characterized by high intensity and short duration.

Mook, H.A. Jr.

1984-01-01T23:59:59.000Z

339

Nuclear diffractive structure functions at high energies  

E-Print Network (OSTI)

A future high-energy electron-ion collider would explore the non-linear weakly-coupled regime of QCD, and test the Color Glass Condensate (CGC) approach to high-energy scattering. Hard diffraction in deep inelastic scattering off nuclei will provide many fundamental measurements. In this work, the nuclear diffractive structure function F_{2,A}^D is predicted in the CGC framework, and the features of nuclear enhancement and suppression are discussed.

Marquet, C; Lappi, T; Venugopalan, R

2008-01-01T23:59:59.000Z

340

Nuclear diffractive structure functions at high energies  

E-Print Network (OSTI)

A future high-energy electron-ion collider would explore the non-linear weakly-coupled regime of QCD, and test the Color Glass Condensate (CGC) approach to high-energy scattering. Hard diffraction in deep inelastic scattering off nuclei will provide many fundamental measurements. In this work, the nuclear diffractive structure function F_{2,A}^D is predicted in the CGC framework, and the features of nuclear enhancement and suppression are discussed.

C. Marquet; H. Kowalski; T. Lappi; R. Venugopalan

2008-05-30T23:59:59.000Z

Note: This page contains sample records for the topic "neutron powder diffraction" 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

Active diffraction gratings: Development and tests  

Science Conference Proceedings (OSTI)

We present the realization and characterization of an active spherical diffraction grating with variable radius of curvature to be used in grazing-incidence monochromators. The device consists of a bimorph deformable mirror on the top of which a diffraction grating with laminar profile is realized by UV lithography. The experimental results show that the active grating can optimize the beam focalization of visible wavelengths through its rotation and focus accommodation.

Bonora, S.; Frassetto, F.; Poletto, L. [Institute of Photonics and Nanotechnologies, National Council for Research of Italy, via Trasea, 7, Padova 35131 (Italy); Zanchetta, E.; Della Giustina, G.; Brusatin, G. [Industrial Engineering Department, University of Padova, Via Marzolo 9, 35131 Padova (Italy)

2012-12-15T23:59:59.000Z

342

Dry powder mixes comprising phase change materials  

DOE Patents (OSTI)

Free flowing, conformable powder-like mix of silica particles and a phase change material (p.c.m.) is disclosed. The silica particles have a critical size of about 7.times.10.sup.-3 to about 7.times.10.sup.-2 microns and the pcm must be added to the silica in an amount of 80 wt. % or less pcm per combined weight of silica and pcm. The powder-like mix can be used in tableware items, medical wraps, tree wraps, garments, quilts and blankets, and in cementitious compositions of the type in which it is beneficial to use a pcm material. The silica-pcm mix can also be admixed with soil to provide a soil warming effect and placed about a tree, flower, or shrub.

Salyer, Ival O. (Dayton, OH)

1993-01-01T23:59:59.000Z

343

Dry powder mixes comprising phase change materials  

DOE Patents (OSTI)

Free flowing, conformable powder-like mix of silica particles and a phase change material (p.c.m.) is disclosed. The silica particles have a critical size of about 7.times.10.sup.-3 to about 7.times.10.sup.-2 microns and the pcm must be added to the silica in an amount of 80 wt. % or less pcm per combined weight of silica and pcm. The powder-like mix can be used in tableware items, medical wraps, tree wraps, garments, quilts and blankets, and in cementitious compositions of the type in which it is beneficial to use a pcm material. The silica-pcm mix can also be admixed with soil to provide a soil warming effect and placed about a tree, flower, or shrub.

Salyer, Ival O. (Dayton, OH)

1992-01-01T23:59:59.000Z

344

Dry powder mixes comprising phase change materials  

DOE Patents (OSTI)

Free flowing, conformable powder-like mix of silica particles and a phase change material (p.c.m.) is disclosed. The silica particles have a critical size of about 7.times.10.sup.-3 to about 7.times.10.sup.-2 microns and the pcm must be added to the silica in an amount of 80 wt. % or less pcm per combined weight of silica and pcm. The powder-like mix can be used in tableware items, medical wraps, tree wraps, garmets, quilts and blankets, and in cementitious compositions of the type in which it is beneficial to use a pcm material. The silica-pcm mix can also be admixed with soil to provide a soil warming effect and placed about a tree, flower, or shrub.

Salyer, Ival O. (Dayton, OH)

1993-01-01T23:59:59.000Z

345

Dry powder mixes comprising phase change materials  

DOE Patents (OSTI)

A free flowing, conformable powder-like mix of silica particles and a phase change material (p.c.m.) is disclosed. The silica particles have a critical size of about 7 [times] 10[sup [minus]3] to about 7 [times] 10[sup [minus]2] microns and the pcm must be added to the silica in an amount of 80 wt. % or less pcm per combined weight of silica and pcm. The powder-like mix can be used in tableware items, medical wraps, tree wraps, garments, quilts and blankets, and in cementitious compositions of the type in which it is beneficial to use a pcm material. The silica-pcm mix can also be admixed with soil to provide a soil warming effect and placed about a tree, flower, or shrub. 9 figs.

Salyer, I.O.

1992-04-21T23:59:59.000Z

346

Dry powder mixes comprising phase change materials  

DOE Patents (OSTI)

Free flowing, conformable powder-like mix of silica particles and a phase change material (p.c.m.) is disclosed. The silica particles have a critical size of about 7[times]10[sup [minus]3] to about 7[times]10[sup [minus]2] microns and the p.c.m. must be added to the silica in an amount of 80 wt. % or less p.c.m. per combined weight of silica and p.c.m. The powder-like mix can be used in tableware items, medical wraps, tree wraps, garments, quilts and blankets, and in cementitious compositions of the type in which it is beneficial to use a p.c.m. material. The silica-p.c.m. mix can also be admixed with soil to provide a soil warming effect and placed about a tree, flower, or shrub.

Salyer, I.O.

1993-05-18T23:59:59.000Z

347

Fabricating solid carbon porous electrodes from powders  

DOE Patents (OSTI)

Fabrication of conductive solid porous carbon electrodes for use in batteries, double layer capacitors, fuel cells, capacitive dionization, and waste treatment. Electrodes fabricated from low surface area (<50 m.sup.2 /gm) graphite and cokes exhibit excellent reversible lithium intercalation characteristics, making them ideal for use as anodes in high voltage lithium insertion (lithium-ion) batteries. Electrodes having a higher surface area, fabricated from powdered carbon blacks, such as carbon aerogel powder, carbon aerogel microspheres, activated carbons, etc. yield high conductivity carbon compositives with excellent double layer capacity, and can be used in double layer capacitors, or for capacitive deionization and/or waste treatment of liquid streams. By adding metallic catalysts to be high surface area carbons, fuel cell electrodes can be produced.

Kaschmitter, James L. (Pleasanton, CA); Tran, Tri D. (Livermore, CA); Feikert, John H. (Livermore, CA); Mayer, Steven T. (San Leandro, CA)

1997-01-01T23:59:59.000Z

348

Dry powder mixes comprising phase change materials  

DOE Patents (OSTI)

Free flowing, conformable powder-like mix of silica particles and a phase change material (PCM) is provided. The silica particles have a critical size of about 0.005 to about 0.025 microns and the PCM must be added to the silica in an amount of 75% or less PCM per combined weight of silica and PCM. The powder-like mix can be used in tableware items, medical wraps, tree wraps, garments, quilts and blankets, and in cementitious compositions of the type in which it is beneficial to use a PCM material. The silica-PCM mix can also be admixed with soil to provide a soil warming effect and placed about a tree, flower, or shrub.

Salyer, Ival O. (Dayton, OH)

1994-01-01T23:59:59.000Z

349

Dry powder mixes comprising phase change materials  

DOE Patents (OSTI)

Free flowing, conformable powder-like mix of silica particles and a phase change material (PCM) is provided. The silica particles have a critical size of about 0.005 to about 0.025 microns and the PCM must be added to the silica in an amount of 75% or less PCM per combined weight of silica and PCM. The powder-like mix can be used in tableware items, medical wraps, tree wraps, garments, quilts and blankets, and in cementitious compositions of the type in which it is beneficial to use a PCM material. The silica-PCM mix can also be admixed with soil to provide a soil warming effect and placed about a tree, flower, or shrub. 2 figures.

Salyer, I.O.

1994-02-01T23:59:59.000Z

350

Fabricating solid carbon porous electrodes from powders  

DOE Patents (OSTI)

Fabrication is described for conductive solid porous carbon electrodes for use in batteries, double layer capacitors, fuel cells, capacitive deionization, and waste treatment. Electrodes fabricated from low surface area (<50 m{sup 2}/gm) graphite and cokes exhibit excellent reversible lithium intercalation characteristics, making them ideal for use as anodes in high voltage lithium insertion (lithium-ion) batteries. Electrodes having a higher surface area, fabricated from powdered carbon blacks, such as carbon aerogel powder, carbon aerogel microspheres, activated carbons, etc. yield high conductivity carbon composites with excellent double layer capacity, and can be used in double layer capacitors, or for capacitive deionization and/or waste treatment of liquid streams. By adding metallic catalysts to high surface area carbons, fuel cell electrodes can be produced. 1 fig.

Kaschmitter, J.L.; Tran, T.D.; Feikert, J.H.; Mayer, S.T.

1997-06-10T23:59:59.000Z

351

Powder River Energy Corporation | Open Energy Information  

Open Energy Info (EERE)

Jump to: navigation, search Jump to: navigation, search Name Powder River Energy Corporation Place Sundance, Wyoming Website precorp.coop/ Utility Id 19156 Utility Location Yes Ownership C NERC Location WECC Activity Distribution Yes References EIA Form EIA-861 Final Data File for 2010 - File1_a[1] SGIC[2] Energy Information Administration Form 826[3] LinkedIn Connections CrunchBase Profile No CrunchBase profile. Create one now! This article is a stub. You can help OpenEI by expanding it. Powder River Energy Corporation Smart Grid Project was awarded $2,554,807 Recovery Act Funding with a total project value of $5,109,614. Utility Rate Schedules Grid-background.png General Service (GS)-Single Phase Commercial General Service (GS)-Three phase Commercial General Service-Coal Bed Methane (GS-CBM)-Single Phase Commercial

352

Advanced neutron absorber materials  

DOE Patents (OSTI)

A neutron absorbing material and method utilizing rare earth elements such as gadolinium, europium and samarium to form metallic glasses and/or noble base nano/microcrystalline materials, the neutron absorbing material having a combination of superior neutron capture cross sections coupled with enhanced resistance to corrosion, oxidation and leaching.

Branagan, Daniel J. (Idaho Falls, ID); Smolik, Galen R. (Idaho Falls, ID)

2000-01-01T23:59:59.000Z

353

Physics @ Oxford SCATTERING NEUTRONS  

E-Print Network (OSTI)

1 Neutron Scattering Society of America (NSSA) Purpose and New Initiatives www.neutronscattering.org SNS/ANL School on Neutron and X-Ray Scattering June 2011 Visit us now on Facebook #12;2 What is the NSSA? NSSA is an organization of scientists and engineers with a common interest in using neutron

Herz, Laura M.

354

Arsenic activation neutron detector  

DOE Patents (OSTI)

A detector of bursts of neutrons from a deuterium-deuteron reaction includes a quantity of arsenic adjacent a gamma detector such as a scintillator and photomultiplier tube. The arsenic is activated by the 2.5-MeV neutrons to release gamma radiation which is detected to give a quantitative representation of detected neutrons.

Jacobs, E.L.

1980-01-28T23:59:59.000Z

355

Counterflow diffusion flame synthesis of ceramic oxide powders  

DOE Patents (OSTI)

Ceramic oxide powders and methods for their preparation are revealed. Ceramic oxide powders are obtained using a flame process whereby one or more precursors of ceramic oxides are introduced into a counterflow diffusion flame burner wherein the precursors are converted into ceramic oxide powders. The nature of the ceramic oxide powder produced is determined by process conditions. The morphology, particle size, and crystalline form of the ceramic oxide powders may be varied by the temperature of the flame, the precursor concentration ratio, the gas stream and the gas velocity.

Katz, Joseph L. (Baltimore, MD); Miquel, Philippe F. (Towson, MD)

1997-01-01T23:59:59.000Z

356

Counterflow diffusion flame synthesis of ceramic oxide powders  

DOE Patents (OSTI)

Ceramic oxide powders and methods for their preparation are revealed. Ceramic oxide powders are obtained using a flame process whereby one or more precursors of ceramic oxides are introduced into a counterflow diffusion flame burner wherein the precursors are converted into ceramic oxide powders. The nature of the ceramic oxide powder produced is determined by process conditions. The morphology, particle size, and crystalline form of the ceramic oxide powders may be varied by the temperature of the flame, the precursor concentration ratio, the gas stream and the gas velocity. 24 figs.

Katz, J.L.; Miquel, P.F.

1997-07-22T23:59:59.000Z

357

Sintering of sponge and hydride-dehydride titanium powders  

Science Conference Proceedings (OSTI)

The sintering behavior of compacts produced from sponge and hydride-dehydride (HDH) Ti powders was examined. Compacts were vacuum sintered at 1200 or 1300 deg C for 30, 60, 120, 240, 480 or 960 minutes. The porosity decreased with sintering time and/or temperature in compacts produced from the HDH powders. Compacts produced from these powders could be sintered to essentially full density. However, the sintering condition did not influence the amount of porosity present in compacts produced from the sponge powders. These samples could only be sintered to a density of 97% theoretical. The sintering behavior was attributed to the chemical impurities in the powders.

Alman, David E.; Gerdemann, Stephen J.

2004-04-01T23:59:59.000Z

358

Biology and Soft Matter Division - ORNL Neutron Sciences  

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

Home › Neutron Sciences Directorate › Biology and Soft Matter Division Home › Neutron Sciences Directorate › Biology and Soft Matter Division Biology and Soft Matter Division Paul Langan, BSMD Director BSMD Director Paul Langan. The Biology and Soft Matter Division (BSMD) operates an external user program for biological and soft matter research using neutron techniques at SNS and HFIR. Division personnel enable the research initiated by external users by acting as instrument responsible scientists and local contacts on a range of different beam lines. BSMD works closely with the Center for Structural Molecular Biology. Diffraction, small-angle scattering, and reflectometry are ideal methods for studying structure and organization from the atomic to the micron length scales, and neutron spectroscopic methods characterize self and

359

In Situ and Time Resolved Synchrotron X-ray Diffraction ...  

Science Conference Proceedings (OSTI)

... and its lower thermal expansion efficiencies. ... makes them unattractive for transmission powder work. ... will highlight current and planned details of ...

2013-04-19T23:59:59.000Z

360

High energy neutron dosimeter  

DOE Patents (OSTI)

A device for measuring dose equivalents in neutron radiation fields is described. The device includes nested symmetrical hemispheres (forming spheres) of different neutron moderating materials that allow the measurement of dose equivalents from 0.025 eV to past 1 GeV. The layers of moderating material surround a spherical neutron counter. The neutron counter is connected by an electrical cable to an electrical sensing means which interprets the signal from the neutron counter in the center of the moderating spheres. The spherical shape of the device allows for accurate measurement of dose equivalents regardless of its positioning. 2 figures.

Rai, K.S.F.

1994-01-11T23:59:59.000Z

Note: This page contains sample records for the topic "neutron powder diffraction" 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

High energy neutron dosimeter  

DOE Patents (OSTI)

A device for measuring dose equivalents in neutron radiation fields. The device includes nested symmetrical hemispheres (forming spheres) of different neutron moderating materials that allow the measurement of dose equivalents from 0.025 eV to past 1 GeV. The layers of moderating material surround a spherical neutron counter. The neutron counter is connected by an electrical cable to an electrical sensing means which interprets the signal from the neutron counter in the center of the moderating spheres. The spherical shape of the device allows for accurate measurement of dose equivalents regardless of its positioning.

Sun, Rai Ko S.F. (Albany, CA)

1994-01-01T23:59:59.000Z

362

Published Research 2009 | ORNL Neutron Sciences  

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

09 09 Published Research 2009 Most publications are in Adobe Portable Document Format. Download Adobe Reader. For more information about any of these publications, please contact the Neutrons Sciences Communications Office. Primary Author Index: A B C D E F G H I J K L M N O P Q R S T U V W X Y Z A A. Abdou, M. Wendel, D. Felde, and B. Riemer, "CFD validation of gas injection in flowing mercury over vertical smooth and grooved wall," Proceedings of the ASME Fluids Engineering Division Summer Conference 2009, FEDSM2009 1 (Part B), 1061-1067 (2009). M. Agamalian, J. M. Carpenter, and J. W. Richardson, "Validity of the Darwin and Ewald reflectivity functions in the range of the far wings: Neutron diffraction study." Physics Letters A 373, 292-295 (2009). A. Alfonsov, E. Vavilova, V. Kataev, B. Büchner, A. Podlesnyak, M.

363

Published Research 2006 | ORNL Neutron Sciences  

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

6 6 Most publications are in Adobe Portable Document Format. Download Adobe Reader. For more information about any of these publications, please contact the Neutrons Sciences Communications Office. Primary Author Index: B C E F G H I J K L M N O P R S T W X Y B E. D. Bauer, A. D. Christianson, J. S. Gardner, V. A. Sidorov, J. D. Thompson, J. L. Sarrao, and M. F. Hundley, "Physical properties of the ferromagnetic heavy-fermion compound UIr2Zn20," Physical Review B 74, (Oct 2006). B. Bennett, P. Langan, L. Coates, M. Mustyakimov, B. Schoenborn, E.E. Howell, C. Dealwis, "Neutron diffraction studies of Escherichia coli dihydrofolate reductase complexed with methotrexate," PNAS of the United States of America 103(49), pp. 18493-8 (5 Dec. 2006). M. L. Benson, P. K. Liaw, H. Choo, T. A. Saleh, D. W. Brown, M. R.

364

Published Research 2009 | ORNL Neutron Sciences  

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

9 9 Most publications are in Adobe Portable Document Format. Download Adobe Reader. For more information about any of these publications, please contact the Neutrons Sciences Communications Office. Primary Author Index: A B C D E F G H I J K L M N O P Q R S T U V W X Y Z A Abdou A., Wendel M., Felde D., Riemer B., "CFD validation of gas injection in flowing mercury over vertical smooth and grooved wall", Proceedings of the ASME Fluids Engineering Division Summer Conference 2009. Agamalian M., Carpenter J. M., Richardson J. W., "Validity of the Darwin and Ewald reflectivity functions in the range of the far wings: neutron diffraction study", Physics Letters A 373, 292-295. Alfonsov A., Vavilova E., Kataev V., Buchner B., Podlesnyak A., Russina M., Furrer A., Strassle Th., Pomjakushina E., Conder K., Khomskii

365

High Energy Diffraction Microscopy at the Advanced Photon Source ...  

Science Conference Proceedings (OSTI)

The APS 1-ID beamline is dedicated to high-energy diffraction and the status of the ... High Energy Diffraction Microscopy at the Advanced Photon Source 1-ID...

366

Spallation Neutron Source, SNS  

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

Spallation Neutron Source Spallation Neutron Source Providing the most intense pulsed neutron beams in the world... Accumulator Ring Commissioning Latest Step for Spallation Neutron Source The Spallation Neutron Source, located at Oak Ridge National Laboratory, has passed another milestone on the way to completion this year--the commissioning of the proton accumulator ring. Brookhaven led the design and construction of the accumulator ring, which will allow an order of magnitude more beam power than any other facility in the world. The Spallation Neutron Source (SNS) is an accelerator-based neutron source being built in Oak Ridge, Tennessee, by the U.S. Department of Energy. The figure on the right shows a schematic of the accumulator ring and transport beam lines that are being designed and built by Brookhaven

367

NEUTRON DENSITY CONTROL IN A NEUTRONIC REACTOR  

DOE Patents (OSTI)

The method and means for controlling the neutron density in a nuclear reactor is described. It describes the method and means for flattening the neutron density distribution curve across the reactor by spacing the absorbing control members to varying depths in the central region closer to the center than to the periphery of the active portion of the reactor to provide a smaller neutron reproduction ratio in the region wherein the members are inserted, than in the remainder of the reactor thereby increasing the over-all potential power output.

Young, G.J.

1959-06-30T23:59:59.000Z

368

Imaging and Neutrons - IAN 2006 - Neutron Sciences  

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

SNS Home Saturday, January 11, 2014 SNS Home Saturday, January 11, 2014 Go IAN 2006 Imaging and Neutrons 2006 October 23-25, 2006 Iran Thomas Auditorium Central Laboratory and Office Building Spallation Neutron Source Oak Ridge National Laboratory, Oak Ridge, TN Who Should Attend Synopsis Goals and Expected Outcomes Application Areas Techniques International Advisory Committee Local Organizing Committee Agenda with Presentations NEW Confirmed Speakers Frequently Asked Questions - FAQ Satellite Workshop - Progress in Electron Volt Neutron Spectroscopy eV Worshop Agenda presentations NEW Lodging, Transportation, Bus Schedule Location Directions and Map Registration CLOSED Abstracts, Posters, Contributed Talks Scholarships Sponsors Vendors May Attend Relevant Reports Important Dates Weather Attractions

369

Large Bore Powder Gun Qualification (U)  

Science Conference Proceedings (OSTI)

A Large Bore Powder Gun (LBPG) is being designed to enable experimentalists to characterize material behavior outside the capabilities of the NNSS JASPER and LANL TA-55 PF-4 guns. The combination of these three guns will create a capability to conduct impact experiments over a wide range of pressures and shock profiles. The Large Bore Powder Gun will be fielded at the Nevada National Security Site (NNSS) U1a Complex. The Complex is nearly 1000 ft below ground with dedicated drifts for testing, instrumentation, and post-shot entombment. To ensure the reliability, safety, and performance of the LBPG, a qualification plan has been established and documented here. Requirements for the LBPG have been established and documented in WE-14-TR-0065 U A, Large Bore Powder Gun Customer Requirements. The document includes the requirements for the physics experiments, the gun and confinement systems, and operations at NNSS. A detailed description of the requirements is established in that document and is referred to and quoted throughout this document. Two Gun and Confinement Systems will be fielded. The Prototype Gun will be used primarily to characterize the gun and confinement performance and be the primary platform for qualification actions. This gun will also be used to investigate and qualify target and diagnostic modifications through the life of the program (U1a.104 Drift). An identical gun, the Physics Gun, will be fielded for confirmatory and Pu experiments (U1a.102D Drift). Both guns will be qualified for operation. The Gun and Confinement System design will be qualified through analysis, inspection, and testing using the Prototype Gun for the majority of process. The Physics Gun will be qualified through inspection and a limited number of qualification tests to ensure performance and behavior equivalent to the Prototype gun. Figure 1.1 shows the partial configuration of U1a and the locations of the Prototype and Physics Gun/Confinement Systems.

Rabern, Donald A. [Los Alamos National Laboratory; Valdiviez, Robert [Los Alamos National Laboratory

2012-04-02T23:59:59.000Z

370

Laser production of articles from powders  

DOE Patents (OSTI)

Method and apparatus for forming articles from materials in particulate form in which the materials are melted by a laser beam and deposited at points along a tool path to form an article of the desired shape and dimensions. Preferably the tool path and other parameters of the deposition process are established using computer-aided design and manufacturing techniques. A controller comprised of a digital computer directs movement of a deposition zone along the tool path and provides control signals to adjust apparatus functions, such as the speed at which a deposition head which delivers the laser beam and powder to the deposition zone moves along the tool path. 20 figs.

Lewis, G.K.; Milewski, J.O.; Cremers, D.A.; Nemec, R.B.; Barbe, M.R.

1998-11-17T23:59:59.000Z

371

Impact dynamics of porous powder. Final report  

SciTech Connect

The shock adiabats have been built experimentally in the range of moderate pressures for three porous materials: Al{sub 2}O{sub 3} wheat flour, and their mixture. The model, which describes the behavior of porous powder materials under large-amplitude dynamic loading, has been constructed. The model applicability to describing the shock wave processes is confirmed by good agreement of the calculated shock adiabats and the data obtained in the experiments. The compressive strength of compacted samples has been determined. The possible trend of further researches is presented in conclusion. 15 refs., 19 figs., 6 tabs.

Titov, V.M.

1995-12-31T23:59:59.000Z

372

Laser production of articles from powders  

DOE Patents (OSTI)

Method and apparatus for forming articles from materials in particulate form in which the materials are melted by a laser beam and deposited at points along a tool path to form an article of the desired shape and dimensions. Preferably the tool path and other parameters of the deposition process are established using computer-aided design and manufacturing techniques. A controller comprised of a digital computer directs movement of a deposition zone along the tool path and provides control signals to adjust apparatus functions, such as the speed at which a deposition head which delivers the laser beam and powder to the deposition zone moves along the tool path.

Lewis, Gary K. (Los Alamos, NM); Milewski, John O. (Santa Fe, NM); Cremers, David A. (Los Alamos, NM); Nemec, Ronald B. (White Rock, NM); Barbe, Michael R. (White Rock, NM)

1998-01-01T23:59:59.000Z

373

Deep inelastic scattering and diffraction at HERA  

Science Conference Proceedings (OSTI)

Recent results on deep inelastic scattering and diffraction at HERA obtained by the H1 and ZEUS experiments are presented. The proton structure function F 2 has been measured with the 1994 data in a new kinematic region of Q 2?2 GeV2 and x?4.510?5. The rise in F 2 with decreasing x persists. Results on the determination of the gluon momentum density of the proton are also presented. The diffractive structure function has been measured using large rapidity gap events. The results are interpreted in terms of the pomeron structure.

Johnny S. T. Ng; on behalf of the H1 and ZEUS collaborations

1996-01-01T23:59:59.000Z

374

NanoComposite Stainless Steel Powder Technologies  

SciTech Connect

Oak Ridge National Laboratory has been investigating a new class of Fe-based amorphous material stemming from a DARPA, Defense Advanced Research Projects Agency initiative in structural amorphous metals. Further engineering of the original SAM materials such as chemistry modifications and manufacturing processes, has led to the development of a class of Fe based amorphous materials that upon processing, devitrify into a nearly homogeneous distribution of nano sized complex metal carbides and borides. The powder material is produced through the gas atomization process and subsequently utilized by several methods; laser fusing as a coating to existing components or bulk consolidated into new components through various powder metallurgy techniques (vacuum hot pressing, Dynaforge, and hot isostatic pressing). The unique fine scale distribution of microstructural features yields a material with high hardness and wear resistance compared to material produced through conventional processing techniques such as casting while maintaining adequate fracture toughness. Several compositions have been examined including those specifically designed for high hardness and wear resistance and a composition specifically tailored to devitrify into an austenitic matrix (similar to a stainless steel) which poses improved corrosion behavior.

DeHoff, R.; Glasgow, C. (MesoCoat, Inc.)

2012-07-25T23:59:59.000Z

375

Iowa Powder Atomization Technologies, Inc. | Department of Energy  

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

Iowa Powder Iowa Powder Atomization Technologies, Inc. America's Next Top Energy Innovator Challenge 6067 likes Iowa Powder Atomization Technologies, Inc. Ames Laboratory Iowa Powder Atomization Technologies, Inc. (IPAT) aims to become a leading domestic titanium powder producer allowing for a paradigm shift in the cost of titanium powders for metal injection molding (MIM) feedstock. Decreasing this cost will create vast opportunities for aerospace, military, biomedical, and consumer applications. Titanium and its fabrication by MIM can become one of the United States' most advanced processing technologies and help jump-start many corresponding manufacturing sectors, spurring job creation and economic growth throughout the United States. Titanium is viewed as one of the most strategic metals of our future. Its

376

Printed Circuit Board Metal Powder Filters for Low Electron Temperatures  

E-Print Network (OSTI)

We report the characterisation of printed circuit boards (PCB) metal powder filters and their influence on the effective electron temperature which is as low as 22 mK for a quantum dot in a silicon MOSFET structure in a dilution refrigerator. We investigate the attenuation behaviour (10 MHz- 20 GHz) of filter made of four metal powders with a grain size below 50 um. The room-temperature attenuation of a stainless steel powder filter is more than 80 dB at frequencies above 1.5 GHz. In all metal powder filters the attenuation increases with temperature. Compared to classical powder filters, the design presented here is much less laborious to fabricate and specifically the copper powder PCB-filters deliver an equal or even better performance than their classical counterparts.

Filipp Mueller; Raymond N. Schouten; Matthias Brauns; Tian Gang; Wee Han Lim; Nai Shyan Lai; Andrew S. Dzurak; Wilfred G. van der Wiel; Floris A. Zwanenburg

2013-04-11T23:59:59.000Z

377

TOTAL DIFFRACTION AND THERMAL DIFFUSE SCATTERING FROM A MULTI-BOUNCE CHANNEL-CUT SINGLE CRYSTAL  

SciTech Connect

We studied Bragg diffraction and Thermal Diffuse Scattering (TDS) from a Si(111) channel-cut triple-bounce crystal using the time-of-flight technique at a pulsed neutron source. Cadmium shielding restricted the detector s direct view of the first bounce surface. The channel-cut crystal dramatically suppresses TDS in the vicinity of the (111), (333) and (444) Bragg reflections; however, TDS appears and increases with the decrease of wavelength in the range of the (555), (777) and (888) orders where cadmium becomes transparent and the single-bounce reflections and TDS contaminate the triple-bounce (555), (777) and (888) reflections.

Carpenter, John M [ORNL; Agamalian, Michael [ORNL

2010-01-01T23:59:59.000Z

378

The Neutron Residual Stress Mapping Facility at HFIR | ORNL Neutron...  

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

Neutron Residual Stress Mapping Facility at HFIR Neutron Residual Stress Mapping Facility (HB-2B) Neutron Residual Stress Mapping Facility (HB-2B). The HB-2B beam port is optimized...

379

Neutron sources and applications  

Science Conference Proceedings (OSTI)

Review of Neutron Sources and Applications was held at Oak Brook, Illinois, during September 8--10, 1992. This review involved some 70 national and international experts in different areas of neutron research, sources, and applications. Separate working groups were asked to (1) review the current status of advanced research reactors and spallation sources; and (2) provide an update on scientific, technological, and medical applications, including neutron scattering research in a number of disciplines, isotope production, materials irradiation, and other important uses of neutron sources such as materials analysis and fundamental neutron physics. This report summarizes the findings and conclusions of the different working groups involved in the review, and contains some of the best current expertise on neutron sources and applications.

Price, D.L. [ed.] [Argonne National Lab., IL (United States); Rush, J.J. [ed.] [National Inst. of Standards and Technology, Gaithersburg, MD (United States)

1994-01-01T23:59:59.000Z

380

PREPARATION OF METAL POWDER COMPACTS PRIOR TO PRESSING  

DOE Patents (OSTI)

A method of fabricating uranium by a powder metallurgical technique is described. It consists in introducing powdered uranium hydride into a receptacle shaped to coincide with the coatour of the die cavity and heating the hydride so that it decomposes to uranium metal. The metal particles cohere in the shapw of the receptacle and thereafter the prefurmed metal powder is pressed and sintered to obtain a dense compact.

Mansfield, H.

1958-08-26T23:59:59.000Z

Note: This page contains sample records for the topic "neutron powder diffraction" 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

DIFFRACTION STUDIES OF ICE Alexe BOSAK  

E-Print Network (OSTI)

as ice-nine [K. Vonnegut, Cat's Cradle] #12;Phase diagram of water #12;Phase diagram of water Here we areDIFFRACTION STUDIES OF ICE Alexeï BOSAK European Synchrotron Radiation Facility #12;Ice as the mild threat ice Ih the only ice in the crust #12;Ice as the absolute weapon Ice IX : melting point 45.8°C

Titov, Anatoly

382

Diffractive and Exclusive Production at the Tevatron  

SciTech Connect

Exclusive Higgs production, in which the event consists of nothing but the leading protons and a Higgs boson, has been proposed as a channel in which to study the properties of the Higgs boson at the Large Hadron Collider (LHC). Although we do not expect to observe exclusive Higgs-boson production at the Tevatron, we can observe similar processes which provide a calibration for theoretical predictions of exclusive Higgs production at the LHC. The CDF measurements of exclusive dijet and diphoton production, examples of such processes, are presented in Sec. 2. Single diffraction has been studied extensively at the Tevatron in Run I, including diffractive dijet and W/Z-boson production. New results with extended kinematical reach allowed by the larger Run II dataset are presented in Sec. 3. CDF II includes forward detectors designed for studying diffractive physics. The MiniPlug calorimeters cover the pseudorapidity region 3.5<|{eta}|<5.1. Beam Shower Counters (BSC) surrounding the beampipe in several locations detect particles in the forward region 5.4<|{eta}|<7.4. A spectrometer consisting of three Roman-pot detectors preceded by Tevatron dipoles is used to track diffractive antiprotons which have lost a fraction 0.03<{zeta}<0.10 of the beam momentum.

Convery, M.E.; Collaboration, for the CDF

2008-10-01T23:59:59.000Z

383

Diffraction gratings used as identifying markers  

DOE Patents (OSTI)

A finely detailed defraction grating is applied to an object as an identifier or tag which is unambiguous, difficult to duplicate, or remove and transfer to another item, and can be read and compared with prior readings with relative ease. The exact pattern of the defraction grating is mapped by diffraction moire techniques and recorded for comparison with future readings of the same grating.

Deason, Vance A. (Idaho Falls, ID); Ward, Michael B. (Idaho Falls, ID)

1991-01-01T23:59:59.000Z

384

Publications from Research Conducted at SNAP | ORNL Neutron Sciences  

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

Publications from Research Conducted at SNAP Publications from Research Conducted at SNAP 2013 Publications Boehler R., Guthrie M., Molaison J.J., dos Santos A. M., Sinogeikin S., Machida S., Pradhan N., Tulk C. A., "Large-volume diamond cells for neutron diffraction above 90 GPa", High Pressure Research 33, 546-554 (2013). Guthrie M., Boehler R., Tulk C. A., Molaison J. J., dos Santos A. M., Li K., Hemley R. J., "Neutron diffraction observations of interstitial protons in dense ice", Proceedings of the National Academy of Sciences of the USA 110, 10552-10556 (2013). Hirai S., dos Santos A. M., Shapiro M. C., Molaison J. J., Pradhan N., Guthrie M., Tulk C. A., Fisher I. R., Mao W. L., "Giant atomic displacement at a magnetic phase transition in metastable Mn3O4", Physical

385

Spallation Neutron Source  

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

D/gim D/gim Spallation Neutron Source SNS is an accelerator-based neutron source. This one-of-a-kind facility pro- vides the most intense pulsed neutron beams in the world. When ramped up to its full beam power of 1.4 MW, SNS will be eight times more powerful than today's best facility. It will give researchers more detailed snapshots of the smallest samples of physical and biological materials than ever before

386

Hazards of black blasting powder in underground coal mining  

SciTech Connect

To help reduce explosion hazards in coal mines using dangerous black blasting powder, this circular outlines precautions designed to increase the safety factor in using this explosive.

Harrington, D.; Warncke, R.G.

1949-01-01T23:59:59.000Z

387

Modeling Metal Powder Compaction Using Combined Finite and ...  

Science Conference Proceedings (OSTI)

Presentation Title, Modeling Metal Powder Compaction Using Combined Finite ... Optimization of Thermal Cycle for Rails with Respect to the Wear Resistance.

388

Injection Molding of Tungsten Powder Treated by Jet Mill  

Science Conference Proceedings (OSTI)

Tungsten powder was firstly treated by jet mill, resulting in the improvement of ... and Welding Conditions of Monopile and Transition for Offshore Wind Plant.

389

Influence of Powder Particle Size Distribution and Pressure on the ...  

Science Conference Proceedings (OSTI)

during HIP were determined as a function of applied pressure, temperature and initial powder particle size distribution for the nickel base superalloy. RENE 95.

390

Powder Metallurgy: A Route to Nanocomposites - Programmaster.org  

Science Conference Proceedings (OSTI)

The formation of coating during mechanical alloying was the results of repetitive cold welding and fracturing of powder particles with each other and with hard...

391

Powder Metallurgy Products for Advanced Gas Turbine Applications  

Science Conference Proceedings (OSTI)

ties for gas turbine a.pplications. At Avco Lycoming, powder metallurgy activity has focused upon a series of high strength nickel base superalloys. These alloys ...

392

Enhanced Control of Powder Yields from Close-Coupled Gas ...  

Science Conference Proceedings (OSTI)

Abstract Scope, Advanced designs for discrete-jet close-coupled (DJ-CC) gas atomization nozzles and melt feed tubes have been developed to enable powder

393

Gas Atomization of Amorphous Aluminum Powder: Part II. Experimental Investigation  

E-Print Network (OSTI)

indicate that cooling rate increases with the increasingthat the cooling rate increases with decreasing powder size.part I, [1] the cooling rate increases with increasing melt

Zheng, Baolong; Lin, Yaojun; Zhou, Yizhang; Lavernia, Enrique J.

2009-01-01T23:59:59.000Z

394

Powder River Basin (WY, MT) Coal and Coalbed Methane: Evaluating...  

Open Energy Info (EERE)

Powder River Basin (WY, MT) Coal and Coalbed Methane: Evaluating and Revising 100 Years of Studies The USGS published a USGS Professional Paper in 2010 entitled

395

Powder River Basin (WY, MT) Coal and Coalbed Methane: Evaluating...  

Open Energy Info (EERE)

Search Share this page on Facebook icon Twitter icon Powder River Basin (WY, MT) Coal and Coalbed Methane: Evaluating and Revising 100 Years of Studies Dataset Summary...

396

Effect of Powder Compact Holding Time on the Microstructure and ...  

Science Conference Proceedings (OSTI)

The microstructure and mechanical properties of Ti-6Al-4V alloy and the effects of powder compact holding time on them were investigated. The results showed...

397

Spark Plasma Sintering of Annular Zirconium Carbide Powder ...  

Science Conference Proceedings (OSTI)

Presentation Title, Spark Plasma Sintering of Annular Zirconium Carbide Powder Pellets:Processing and Simulation. Author(s), Xialu Wei, Wei Li, Eugene A.

398

REPORT: Direct Laser Powder Deposition State of the Art  

Science Conference Proceedings (OSTI)

Dec 11, 2007 ... This report describes the Direct Laser Powder Deposition (DLPD) process known by various names, including Directed Light Fabrication...

399

Vacuum Attachment for Collection of Lithium Powder ---- Inventor...  

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

Vacuum Attachment for Collection of Lithium Powder ---- Inventor(s) Hans Schneider and Stephan Jurczynski The Vacuum Attachment is part of an integrated system designed to collect...

400

Spark Plasma Sintering of Iron and Titanium Powders by ...  

Science Conference Proceedings (OSTI)

Mixtures of titanium and iron powders were activated in kerosene by high-voltage electrical discharges with different electrical discharge numbers.

Note: This page contains sample records for the topic "neutron powder diffraction" 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

Properties of Conventionally Alloyed and Powder Alloyed Nano ...  

Science Conference Proceedings (OSTI)

Presentation Title, Properties of Conventionally Alloyed and Powder Alloyed Nano-Crystalline Titanium Consolidated Via Spark Plasma Sintering. Author(s)...

402

Development and Characterization of Milled Silver Powder Addition ...  

Science Conference Proceedings (OSTI)

In order to add the milled Ag powders to granular PP feedstock two different .... Membranes Obtained from PA6/HDPE Blends Via Precipitation by Immersion.

403

Properties of IN-100 Processed by Powder Metallurgy  

Science Conference Proceedings (OSTI)

PROPERTIES OF IN-100 PROCESSED. BY POWDER METALLURGY. L.N. Moskowitz,. R.M. Pelloux and N.J. Grant. Department of Metallurgy and Materials.

404

The Microstructure and Mechanical Properties of EP741NP Powder ...  

Science Conference Proceedings (OSTI)

properties of powder metallurgy superalloys have been studied as part of an on- going effort ... metallurgy and mechanical property capabilities of EP741NP and.

405

Powder Processing and Mechanical Properties - Programmaster.org  

Science Conference Proceedings (OSTI)

Oct 18, 2010 ... The ball milling of powders has become a powerful method to synthesize metastable structures. Mechanical milling - the ball milling of single...

406

Additive Manufacturing and Novel Consolidation of Powder Materials  

Science Conference Proceedings (OSTI)

Mar 6, 2013 ... Novel Synthesis and Consolidation of Powder Materials : Additive ... HIP and CIP -Sinter techniques do not need lubricants that can react with...

407

Measuring Thermal Conductivity of Powder Insulation at Cryogenic Temperatures.  

E-Print Network (OSTI)

?? A device to measure bulk effective thermal conductivity of powder insulation at cryogenic temperatures has been designed and tested. The design consists of two (more)

Barrios, Matthew Nicklas

2006-01-01T23:59:59.000Z

408

Nano-structured Powders Prepared by Spray Drying and Heat ...  

Science Conference Proceedings (OSTI)

Abstract Scope, Eeconomical method for making nano-sized powders such as silicon or colbalt oxides and electrochemical properties of nano-sized oxide...

409

Process for synthesizing compounds from elemental powders and product  

DOE Patents (OSTI)

A process for synthesizing intermetallic compounds from elemental powders. The elemental powders are initially combined in a ratio which approximates the stoichiometric composition of the intermetallic compound. The mixed powders are then formed into a compact which is heat treated at a controlled rate of heating such that an exothermic reaction between the elements is initiated. The heat treatment may be performed under controlled conditions ranging from a vacuum (pressureless sintering) to compression (hot pressing) to produce a desired densification of the intermetallic compound. In a preferred form of the invention, elemental powders of Fe and Al are combined to form aluminide compounds of Fe.sub.3 Al and FeAl.

Rabin, Barry H. (Idaho Falls, ID); Wright, Richard N. (Idaho Falls, ID)

1993-01-01T23:59:59.000Z

410

Industry - ORNL Neutron Sciences  

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

Industry banner Industry banner Neutron scattering research has applications in practically every field, and neutron research at ORNL is leading to productive partnerships with the industrial and business communities. We welcome proposals for all types of research, including those involving proprietary work. Recent studies have led to discoveries with potential applications in fields such as medicine, energy, and various metals technologies. For more information, please see our recent research highlights. Research Collaborations Industry-Driven Research Benefits Plastics Manufacturing Corning uses VULCAN to test limits of ceramic material for car emission controls, filtration devices Neutrons Probe Inner Workings of Batteries Industry and Neutron Science: Working To Make a Match

411

Neutron-detection apparatus  

DOE Patents (OSTI)

An atomic fission counting apparatus used for neutron detection is provided with spirally curved electrode plates uniformly spaced apart in a circular array and coated with fissile material.

Kopp, M.K.; Valentine, K.H.

1981-04-24T23:59:59.000Z

412

Education | ORNL Neutron Sciences  

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

Matter Physics Neutron Scattering in Quantum Condensed Matter Physics flyer The first cyber enabled collaborative graduate course was launched in Fall semester 2012. It addresses...

413

Neutron Scattering Web  

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

at neutronsources.org. The information contained here in the Neutron Scattering Web has been transferred to the new site. We will leave the current content here for...

414

Magnetization of neutron matter  

SciTech Connect

In this paper, we compute magnetization of neutron matter at strong magnetic field using the lowest order constrained variational (LOCV) technique.

Bigdeli, M. [Department of Physics, Zanjan University, P.O. Box 45195-313, Zanjan (Iran, Islamic Republic of)

2011-09-21T23:59:59.000Z

415

Physics Out Loud - Neutron  

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

Matter Previous Video (Matter) Physics Out Loud Main Index Next Video (Niobium) Niobium Neutron Karl Slifer, a physicist based at the University of New Hampshire and who conducts...

416

Neutron Scattering Facilities  

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

Gaithersburg, Maryland, USA Peruvian Institute of Nuclear Energy (IPEN), Lima, Peru Spallation Neutron Source, Oak Ridge National Laboratory, Tennessee, USA University of...

417

Neutron Activation Calculator  

Science Conference Proceedings (OSTI)

... and incoherent scattering cross sections). Source neutrons (Ang, meV or m/s), Density (g/cm 3 or lattice), Thickness (cm). ...

418

Neutron Spin Filters  

Science Conference Proceedings (OSTI)

... many nice scientific results from the use of high intensity polarized neutrons ... Electromagnetic radiation of exactly the right energy can exert a sort of ...

2013-03-12T23:59:59.000Z

419

Neutron Scattering Template  

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

Acknowledgements The graphics used on the Neutron Scattering Web Pages were designed by Tami Sharley (Information and Publishing Services Division) and Jack Carpenter (Intense...

420

Neutrons in Biology, ORNL  

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

Scattering Sciences Division Oak Ridge National Laboratory Phone: 865.241.2897 SNS Logo HFIR Logo General Information The unique potential of neutron scattering in structural...

Note: This page contains sample records for the topic "neutron powder diffraction" 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

Neutrons in Biology, ORNL  

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

Scattering Sciences Division Oak Ridge National Laboratory Phone: 865.576.2779 SNS Logo HFIR Logo General Information The unique potential of neutron scattering in structural...

422

Neutrons in Biology, ORNL  

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

Materials Division Oak Ridge National Laboratory Phone: 865.241.5176 SNS Logo HFIR Logo General Information The unique potential of neutron scattering in structural...

423

ORNL Neutron Sciences Publications  

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

at other facilties by Neutron Sciences Directorate staff. We strongly encourage SNS and HFIR users to submit citation information, including URLs, for all publications regarding...

424

Towards a Neutron Microscope  

Science Conference Proceedings (OSTI)

Towards a Neutron Microscope. Summary: ... The novel lens is a Wolter Optic similar in design to the telescope of the CHANDRA x-ray observatory. ...

2013-07-23T23:59:59.000Z

425

NCNR Neutron Spin Filters  

Science Conference Proceedings (OSTI)

... be characterized either by the transmission asymmetry A ... defined to be the transmissions for neutrons ... P sub n, (solid thick line), transmission T sub n ...

426

Neutron detection apparatus  

DOE Patents (OSTI)

An atomic fission counting apparatus used for neutron detection is provided with spirally curved electrode plates uniformly spaced apart in a circular array and coated with fissile material.

Kopp, Manfred K. (Oak Ridge, TN); Valentine, Kenneth H. (Lenoir City, TN)

1983-01-01T23:59:59.000Z

427

Neutrons in Soft Matter Science | Education | ORNL Neutron Sciences  

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

Complex Materials on Mesoscopic Scales Neutron in Soft Matter Science flyer The new cyber-enabled collaborative graduate course "Neutrons in Soft Matter Science: Complex...

428

Neutron Science Facilities Operating Status | ORNL Neutron Sciences  

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

Neutron Science Facilities Operating Status High Flux Isotope Reactor The reactor is currently operating at 100% power for fuel cycle 449. Spallation Neutron Source SNS is shutdown...

429

Neutronic Aspects and Recent Experimental Results with ...  

Science Conference Proceedings (OSTI)

... Neutronic Aspects and Recent Experimental Results with Methane Moderators at IUCF Low Energy Neutron Source (LENS). ...

430

Solution Synthesis and Processing of PZT Materials for Neutron Generator Applications  

SciTech Connect

A new solution synthesis route has been developed for the preparation of lead-based ferroelectric materials (patent filed). The process produces controlled stoichiometry precursor powders by non-aqueous precipitation. For a given ferroelectric material to be prepared, a metal acetate/alkoxide solution containing constituent metal species in the appropriate ratio is mixed with an oxalic acid/n-propanol precipitant solution. An oxalate coprecipitate is instantly fonned upon mixing that quantitatively removes the metals from solution. Most of the process development was focused on the synthesis and processing of niobium-substituted lead zirconate titanate with a Zr-to-Ti ratio of 95:5 (PNZT 95/5) that has an application in neutron generator power supplies. The process was scaled to produce 1.6 kg of the PNZT 95/5 powder using either a sen-ii-batch or a continuous precipitation scheme. Several of the PNZT 95/5 powder lots were processed into ceramic slug form. The slugs in turn were processed into components and characterized. The physical properties and electrical performance (including explosive functional testing of the components met the requirements set for the neutron generator application. Also, it has been demonstrated that the process is highly reproducible with respect to the properties of the powders it produces and the properties of the ceramics prepared from its powders. The work described in this report was funded by Sandia's Laboratory Directed Research and Development Program.

Anderson, M.A.; Ewsuk, K.G.; Montoya, T.V.; Moore, R.H.; Sipola, D.L.; Tuttle, B.A.; Voigt, J.A.

1998-12-01T23:59:59.000Z

431

electronic reprint Crystallography  

E-Print Network (OSTI)

-plate single-crystal silicon sample holders for neutron powder diffraction studies of highly absorbing ­ all rights reserved Flat-plate single-crystal silicon sample holders for neutron powder diffraction 459, Station 18, Chalk River Laboratories, Chalk River, Ontario, Canada K0J 1J0. Correspondence e

Ryan, Dominic

432

Apparatus for producing nanoscale ceramic powders  

DOE Patents (OSTI)

An apparatus provides high temperature and short residence time conditions for the production of nanoscale ceramic powders. The apparatus includes a confinement structure having a multiple inclined surfaces for confining flame located between the surfaces so as to define a flame zone. A burner system employs one or more burners to provide flame to the flame zone. Each burner is located in the flame zone in close proximity to at least one of the inclined surfaces. A delivery system disposed adjacent the flame zone delivers an aerosol, comprising an organic or carbonaceous carrier material and a ceramic precursor, to the flame zone to expose the aerosol to a temperature sufficient to induce combustion of the carrier material and vaporization and nucleation, or diffusion and oxidation, of the ceramic precursor to form pure, crystalline, narrow size distribution, nanophase ceramic particles.

Helble, Joseph J. (Andover, MA); Moniz, Gary A. (Windham, NH); Morse, Theodore F. (Little Compton, RI)

1995-09-05T23:59:59.000Z

433

Apparatus for producing nanoscale ceramic powders  

SciTech Connect

An apparatus provides high temperature and short residence time conditions for the production of nanoscale ceramic powders. The apparatus includes a confinement structure having a multiple inclined surfaces for confining flame located between the surfaces so as to define a flame zone. A burner system employs one or more burners to provide flame to the flame zone. Each burner is located in the flame zone in close proximity to at least one of the inclined surfaces. A delivery system disposed adjacent the flame zone delivers an aerosol, comprising an organic or carbonaceous carrier material and a ceramic precursor, to the flame zone to expose the aerosol to a temperature sufficient to induce combustion of the carrier material and vaporization and nucleation, or diffusion and oxidation, of the ceramic precursor to form pure, crystalline, narrow size distribution, nanophase ceramic particles. 5 figs.

Helble, J.J.; Moniz, G.A.; Morse, T.F.

1995-09-05T23:59:59.000Z

434

Apparatus for producing nanoscale ceramic powders  

DOE Patents (OSTI)

An apparatus provides high temperature and short residence time conditions for the production of nanoscale ceramic powders. The apparatus includes a confinement structure having a multiple inclined surfaces for confining flame located between the surfaces so as to define a flame zone. A burner system employs one or more burners to provide flame to the flame zone. Each burner is located in the flame zone in close proximity to at least one of the inclined surfaces. A delivery system disposed adjacent the flame zone delivers an aerosol, comprising an organic or carbonaceous carrier material and a ceramic precursor, to the flame zone to expose the aerosol to a temperature sufficient to induce combustion of the carrier material and vaporization and nucleation, or diffusion and oxidation, of the ceramic precursor to form pure, crystalline, narrow size distribution, nanophase ceramic particles.

Helble, Joseph J. (Andover, MA); Moniz, Gary A. (Windham, NH); Morse, Theodore F. (Little Compton, RI)

1997-02-04T23:59:59.000Z

435

Apparatus for producing nanoscale ceramic powders  

SciTech Connect

An apparatus provides high temperature and short residence time conditions for the production of nanoscale ceramic powders. The apparatus includes a confinement structure having a multiple inclined surfaces for confining flame located between the surfaces so as to define a flame zone. A burner system employs one or more burners to provide flame to the flame zone. Each burner is located in the flame zone in close proximity to at least one of the inclined surfaces. A delivery system disposed adjacent the flame zone delivers an aerosol, comprising an organic or carbonaceous carrier material and a ceramic precursor, to the flame zone to expose the aerosol to a temperature sufficient to induce combustion of the carrier material and vaporization and nucleation, or diffusion and oxidation, of the ceramic precursor to form pure, crystalline, narrow size distribution, nanophase ceramic particles. 5 figs.

Helble, J.J.; Moniz, G.A.; Morse, T.F.

1997-02-04T23:59:59.000Z

436

Synchrotron Mossbauer Spectroscopy of powder samples  

SciTech Connect

Synchrotron Mossbauer Spectroscopy, SMS, is an emerging technique that allows fast and accurate determination of hyperfine field parameters similar to conventional Mossbauer spectroscopy with radioactive sources. This new technique, however, is qualitatively different from Mossbauer spectroscopy in terms of equipment, methodology, and analysis to warrant a new name. In this paper, the authors report on isomer shift and quadrupole splitting measurements of Mohr`s salt, Fe(NH{sub 4}){sub 2}(SO{sub 4}){sub 2}{center_dot}6H{sub 2}O for demonstration purposes. Theoretical calculations were performed and compared to experiments both in energy and time domain to demonstrate the influence of thickness distribution and preferential alignment of powder samples. Such measurements may prove to be useful when the data collection times are reduced to few seconds in the third generation, undulator based synchrotron radiation sources.

Alp, E.E.; Sturhahn, W.; Toellner, T.

1994-08-01T23:59:59.000Z

437

Detonation Diffraction into a Confined Volume  

E-Print Network (OSTI)

Detonation diffraction has been, and remains, an active area of research. However, detonation diffraction into a confined volume, and specifically the transformation of a planar detonation into a cylindrical detonation, is an area which has received little attention. Experimental work needs to be conducted on detonation diffraction into a confined volume to better understand how the interaction of the diffracted shock wave with a confining wall impacts the detonation diffraction process. Therefore, a facility was constructed to study this problem, and experiments were conducted to determine under what conditions a planar detonation could be successfully transformed into a cylindrical detonation. Four different fuel-oxidizer mixtures, C?H?+ 2.5 O?, C?H?+ 4 O?, C?H?+ 3 O? and H?+ 0.5 O?, were tested in this study using a combination of pressure transducers and soot foil records as diagnostics. Three different regimes of successful transmission; spontaneous re-ignition, continuous reflected re-initiation, and discontinuous reflected re-initiation, were identified. The detonation cell size and the distance from the tube exit to the confining wall, or gap size, were determined to be the most important parameters in the transmission process and a linear correlation for determining whether or not transmission will be successful for a given set of initial conditions was developed for gap sizes between 10 and 35 mm. For gap sizes smaller than 10 mm or gap size larger than 35 mm the linear correlation does not apply. Finally, the results of this study are compared to results on detonation diffraction into a confined volume available in the literature and explanations for any disagreements are given. This study showed that when compared to transmission of a detonation into an unconfined volume, the transmission of a detonation into a confined volume, for the majority of gap sizes, is possible for a wider range of conditions. However, for extremely small gap sizes, when compared to transmission into an unconfined volume, the range of conditions for which successful transmission is possible into a confined volume is actually narrower.

Polley, Nolan Lee

2010-12-01T23:59:59.000Z

438

NIST: NIF - Neutron Imaging Facility  

Science Conference Proceedings (OSTI)

... 1 above) is located at Beam Tube 2 (BT-2 ... Figure 2. Plan view of the neutron imaging facility ... still a significant amount of high energy neutrons and ...

439

News & Awards | Neutron Science | ORNL  

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

Awards Events and Conferences Supporting Organizations Neutron Science Home | Science & Discovery | Neutron Science | News and Awards SHARE News and Awards 1-6 of 6 Results...

440

Neutron and Nano User Meeting  

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

Home Science @ Neutron and Nano Facilities User Workshops Integrated Agendas Venue Travel Information Contacts and Sponsors Registration Talks Neutron and Nano User Meeting August...

Note: This page contains sample records for the topic "neutron powder diffraction" 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

Neutron and Nano User Meeting  

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

Science @ Neutron and Nano Facilities Science @ Neutron and Nano Facilities: Complementary Techniques Oak Ridge National Laboratory, Building 5200 Tuesday-Wednesday, August 13-14,...

442

FAST NEUTRON REACTOR  

DOE Patents (OSTI)

A reactor comprising fissionable material in concentration sufficiently high so that the average neutron enengy within the reactor is at least 25,000 ev is described. A natural uranium blanket surrounds the reactor, and a moderating reflector surrounds the blanket. The blanket is thick enough to substantially eliminate flow of neutrons from the reflector.

Soodak, H.; Wigner, E.P.

1961-07-25T23:59:59.000Z

443

Phase-shifting point diffraction interferometer  

DOE Patents (OSTI)

Disclosed is a point diffraction interferometer for evaluating the quality of a test optic. In operation, the point diffraction interferometer includes a source of radiation, the test optic, a beam divider, a reference wave pinhole located at an image plane downstream from the test optic, and a detector for detecting an interference pattern produced between a reference wave emitted by the pinhole and a test wave emitted from the test optic. The beam divider produces separate reference and test beams which focus at different laterally separated positions on the image plane. The reference wave pinhole is placed at a region of high intensity (e.g., the focal point) for the reference beam. This allows reference wave to be produced at a relatively high intensity. Also, the beam divider may include elements for phase shifting one or both of the reference and test beams.

Medecki, Hector (Berkeley, CA)

1998-01-01T23:59:59.000Z

444

Phase-shifting point diffraction interferometer  

DOE Patents (OSTI)

Disclosed is a point diffraction interferometer for evaluating the quality of a test optic. In operation, the point diffraction interferometer includes a source of radiation, the test optic, a beam divider, a reference wave pinhole located at an image plane downstream from the test optic, and a detector for detecting an interference pattern produced between a reference wave emitted by the pinhole and a test wave emitted from the test optic. The beam divider produces separate reference and test beams which focus at different laterally separated positions on the image plane. The reference wave pinhole is placed at a region of high intensity (e.g., the focal point) for the reference beam. This allows reference wave to be produced at a relatively high intensity. Also, the beam divider may include elements for phase shifting one or both of the reference and test beams. 8 figs.

Medecki, H.

1998-11-10T23:59:59.000Z

445

Sinterable powders from laser driven reactions : final report  

E-Print Network (OSTI)

Extremely fine, uniform ceramic powders have been synthesized from Sil4 NH3 and C2H4 gas phase reactants that are heated by absorbing optical energy emitted from a C02 laser. Resulting Si, Si3N4 and SiC powders have been ...

Haggerty, John Scarseth

1981-01-01T23:59:59.000Z

446

Neutron Scattering Software  

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

Software Software A new portal for neutron scattering has just been established at neutronsources.org. The information contained here in the Neutron Scattering Web has been transferred to the new site. We will leave the current content here for archival purposes but no new content will be added. We encourage everyone interested in neutron scattering to take full advantage of this exciting new resource for our community. Neutronsources.org Data Formats NeXus: Neutron and X-ray Data Format Crystallographic Binary Format (CBF/imgCIF) Hierarchical Data Format (HDF) Data Analysis and Visualization Data Analysis for Neutron Scattering Experiments (DANSE): distributed data analysis project Large Array Manipulation Program (LAMP): IDL-based data analysis and visualization

447

Industry - ORNL Neutron Sciences  

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

Industry and Neutron Science Industry and Neutron Science Industry and Neutron Science: Working To Make a Match "In fundamental research, we want to know everything. Industry wants to know enough to answer a question." Research Contact: Mike Crawford September 2011, Written by Deborah Counce Mike Crawford and Souleymane Diallo Mike Crawford of Dupont (right) and Souleymane Diallo, instrument scientist for the Backscattering Spectrometer at SNS, prepare a material sample for an experiment on the instrument. Industrial users are starting to eye the potential of neutron science for solving problems that can't be solved in any other way. At the same time, the SNS and HFIR neutron science facilities at ORNL are exploring ways to woo such users and to make a match of it, to the benefit of both.

448

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

449

THERMAL NEUTRON BACKSCATTER IMAGING.  

DOE Green Energy (OSTI)

Objects of various shapes, with some appreciable hydrogen content, were exposed to fast neutrons from a pulsed D-T generator, resulting in a partially-moderated spectrum of backscattered neutrons. The thermal component of the backscatter was used to form images of the objects by means of a coded aperture thermal neutron imaging system. Timing signals from the neutron generator were used to gate the detection system so as to record only events consistent with thermal neutrons traveling the distance between the target and the detector. It was shown that this time-of-flight method provided a significant improvement in image contrast compared to counting all events detected by the position-sensitive {sup 3}He proportional chamber used in the imager. The technique may have application in the detection and shape-determination of land mines, particularly non-metallic types.

VANIER,P.; FORMAN,L.; HUNTER,S.; HARRIS,E.; SMITH,G.

2004-10-16T23:59:59.000Z

450

Pulsed neutron detector  

DOE Patents (OSTI)

A pulsed neutron detector and system for detecting low intensity fast neutron pulses has a body of beryllium adjacent a body of hydrogenous material the latter of which acts as a beta particle detector, scintillator, and moderator. The fast neutrons (defined as having En>1.5 MeV) react in the beryllium and the hydrogenous material to produce larger numbers of slow neutrons than would be generated in the beryllium itself and which in the beryllium generate hellium-6 which decays and yields beta particles. The beta particles reach the hydrogenous material which scintillates to yield light of intensity related to the number of fast neutrons. A photomultiplier adjacent the hydrogenous material (scintillator) senses the light emission from the scintillator. Utilization means, such as a summing device, sums the pulses from the photo-multiplier for monitoring or other purposes.

Robertson, deceased, J. Craig (late of Albuquerque, NM); Rowland, Mark S. (Livermore, CA)

1989-03-21T23:59:59.000Z

451

Diffractive phenomena in high energy processes  

E-Print Network (OSTI)

We review the evolution of the studies of diffractive processes in the strong interaction over the last 60 years. First, we briefly outline the early developments of the theory based on analyticity and unitarity of the S-matrix, including the derivation and exploration of the Regge trajectories and related moving cuts. Special attention is paid to the concept of the Pomeron trajectory introduced for description of total, elastic and diffractive cross sections at high energies and to the emergence of the dynamics of multi-Pomeron interactions.The role of large longitudinal distances and color coherent phenomena for the understanding of inelastic diffraction in hadron-hadron scattering and deep inelastic scattering is emphasized. The connection of these phenomena to the cancellation of the contribution of the Glauber approximation in hadron-nucleus collisions and to the understanding of the Gribov-Glauber approximation is explained. The presence of different scales in perturbative QCD due to masses of heavy quarks has led to the emergence of numerous new phenomena including non-universality of the slopes of Regge trajectories made of light and heavy quarks and non-universal energy dependence of elastic cross sections. The application of the perturbative QCD techniques allowed us to calculate from the first principles the interaction of small transverse size color singlets with hadrons leading to the development of the quantitative theory of hard exclusive reactions and to the successful prediction of many regularities in hard large mass diffraction. It also led to the prediction of the phenomenon of complete transparency of nuclear matter in QCD in special processes. The conflict of perturbative QCD with probability conservation for high energy processes of virtual photon-nucleon scattering is explained. Some properties of the new QCD regime are outlined.

Leonid Frankfurt; Mark Strikman

2013-04-16T23:59:59.000Z

452

Diffraction smoothing aperture for an optical beam  

SciTech Connect

The disclosure is directed to an aperture for an optical beam having an irregular periphery or having perturbations imposed upon the periphery to decrease the diffraction effect caused by the beam passing through the aperture. Such apertures are particularly useful with high power solid state laser systems in that they minimize the problem of self-focusing which frequently destroys expensive components in such systems.

Judd, O' Dean P. (Los Alamos, NM); Suydam, Bergen R. (Los Alamos, NM)

1976-01-01T23:59:59.000Z

453

Diffraction gratings used as identifying markers  

DOE Patents (OSTI)

A finely detailed defraction grating is applied to an object as an identifier or tag which is unambiguous, difficult to duplicate, or remove and transfer to another item, and can be read and compared with prior readings with relative ease. The exact pattern of the defraction grating is mapped by diffraction moire techniques and recorded for comparison with future readings of the same grating. 7 figs.

Deason, V.A.; Ward, M.B.

1989-08-03T23:59:59.000Z

454

Field implementation of geophysical diffraction tomography  

SciTech Connect

Geophysical diffraction tomography is a new technique that shows promise as a tool for quantitative subsurface (below-ground) imaging. The approach being used is based upon the filtered backpropagation algorithm, which is a mathematical extension of the reconstruction software used in conventional X-ray CAT scanners. The difference between this method and existing methods is that the new algorithm rigorously accounts for diffraction effects through an exact inversion of the wave equation. This refinement is necessary in that it admits the use of acoustic and long-wavelength electromagnetic waves, allowing tomography to be taken from the laboratory to the field. ORNL's effort in geophysical diffraction tomography involves reducing the filtered backpropagation algorithm to practice. This requires the design and construction of field instrumentation as well as the development of an improved algorithm. The original algorithm requires the imaged region to be illuminated by plane waves. This requirement simplifies the algorithm but complicates its field implementation in that plane waves are difficult to generate. Consequently, ORNL has been working to generalize the filtered backpropagation algorithm to allow a broader range of incoming wave fields which can more easily be realized in the field. The instrumentation aspects involve the selection of appropriate sonic sources and receivers along with the development of a state-of-art, portable, computer-controlled, multichannel data acquisition system. 5 references, 6 figures.

Witten, A.J.; Stevens, S.S.

1984-01-01T23:59:59.000Z

455

Chemical & EngChemical/Engineering Materials Division | Neutron Science |  

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

Chemical and Engineering Materials Division Chemical and Engineering Materials Division SHARE Chemical and Engineering Materials Division CEMD Director Mike Simonson The Chemical and Engineering Materials Division (CEMD) supports neutron-based research at SNS and HFIR in understanding the structure and dynamics of chemical systems and novel engineering materials. The user community takes advantage of division-supported capabilities of neutron scattering for measurements over wide ranges of experimental and operating conditions, including studies of chemical and physical changes in situ. User experiments with diffraction, small-angle scattering, inelastic and quasielastic scattering, and neutron imaging instruments address a range of problems in chemistry and in engineering materials research. Current areas of research supported by the division include the structure

456

Residual stress measurement using the pulsed neutron source at LANSCE  

Science Conference Proceedings (OSTI)

The presence of residual stress in engineering components can effect their mechanical properties and structural integrity. Neutron diffraction is the only measuring technique which can make spatially resolved non-destructive strain measurements in the interior of components. By recording the change in the crystalline interplanar spacing, elastic strains can be measured for individual lattice reflections. Using a pulsed neutron source, all the lattice reflections are recorded in each measurement which allows anisotropic effects to be studied. Measurements made at the Manuel Lujan Jr Neutron Scattering Centre (LANSCE) demonstrate the potential for stress measurements on a pulsed source and indicate the advantages and disadvantages over measurements made on a reactor. 15 refs., 7 figs.

Bourke, M.A.M.; Goldstone, J.A. (Los Alamos National Lab., NM (USA)); Holden, T.M. (Atomic Energy of Canada Ltd., Chalk River, ON (Canada))

1991-01-01T23:59:59.000Z

457

Physics of solar neutron production: Questionable detection of neutrons  

E-Print Network (OSTI)

) A short introduction is given to astrophysics of neutron stars and to physics of dense matter in neutron stars. Observed properties of astro- physical objects containing neutron stars are discussed. Current scenarios regarding formation and evolution of neutron stars in those objects are presented. Physical

Share, Gerald

458

Infrared Imaging of Temperature Distribution in a High Temperature X-Ray Diffraction Furnace  

Science Conference Proceedings (OSTI)

High Temperature X-ray Diffraction (HTXRD) is a very powerful tool for studies of reaction kinetics, phase transformations, and lattice thermal expansion of advanced materials. Accurate temperature measurement is a critical part of the technique. Traditionally, thermocouples, thermistors, and optical pyrometers have been used for temperature control and measurement and temperature could only be measured at a single point. Infrared imaging was utilized in this study to characterize the thermal gradients resulting from various sample and furnace configurations in a commercial strip heater furnace. Furnace configurations include a metallic strip heater, with and without a secondary surround heater, or a surround heater alone. Sample configurations include low and high thermal conductivity powders and solids. The IR imaging results have been used to calibrate sample temperatures in the HTXRD furnace.

Payzant, E.A.; Wang, H.

1999-04-05T23:59:59.000Z

459

Homogeneous Precipitation of Nickel Hydroxide Powders  

SciTech Connect

Precipitation and characterization of nickel hydroxide powders were investigated. A comprehensive precipitation model incorporating the metal ion hydrolysis, complexation and precipitation reactions was developed for the production of the powders with urea precipitation method. Model predictions on Ni{sup 2+} precipitation rate were confirmed with precipitation experiments carried out at 90 C. Experimental data and model predictions were in remarkable agreement. Uncertainty in the solubility product data of nickel hydroxides was found to be the large contributor to the error. There were demonstrable compositional variations across the particle cross-sections and the growth mechanism was determined to be the aggregation of primary crystallites. This implied that there is a change in the intercalate chemistry of the primary crystallites with digestion time. Predicted changes in the concentrations of simple and complex ions in the solution support the proposed mechanism. The comprehensive set of hydrolysis reactions used in the model described above allows the investigation of other systems provided that accurate reaction constants are available. the fact that transition metal ions like Ni{sup 2+} form strong complexes with ammonia presents a challenge in the full recovery of the Ni{sup 2+}. On the other hand, presence of Al{sup 3+} facilitates the complete precipitation of Ni{sup 2+} in about 3 hours of digestion. A challenge in their predictive modeling studies had been the fact that simultaneous incorporation of more than one metal ion necessitates a different approach than just using the equilibrium constants of hydrolysis, complexation and precipitation reactions. Another limitation of using equilibrium constants is that the nucleation stage of digestion, which is controlled mainly by kinetics, is not fully justified. A new program released by IBM Almaden Research Center (Chemical Kinetics Simulator{trademark}, Version 1.01) lets the user change the order of kinetic components of a reaction which was set to stoichiometric constant with which the species appear in the reaction in KINSIM by default. For instance, in the case of LDH precipitation, the new program allows to change the order of species in the reactions associated with Al{sup 3+} and let the Ni{sup 2+} reactions take over. This could be carried on iteratively until a good fit between the experimental data and the predictions were observed. However for such studies availability of accurate equilibrium constants (especially for the solubility products for the solid phase) is a prerequisite.

Bora Mavis

2003-12-12T23:59:59.000Z

460

Versatile neutron NDA  

SciTech Connect

Non-destructive analysis (NDA) of bulk samples is a major tool in international safeguards and domestic MC&A. Yet, enhancements are needed to reduce inspection time, financial cost, and radiation exposure-while improving reliability and accuracy-particularly for mixtures of fissile and fertile isotopes. Perhaps the greatest remaining direction for NDA improvement is the development of a single controllable neutron source that would add versatility and capability. One of the primary prospects is a switchable radioactive neutron source (SRNS) that has been under advanced-concept development at Argonne with DOE funding. The SRNS would be in a sealed capsule that can be remotely switched on and off, or pulsed at a controllable rate. Li({alpha}, n) or Be({alpha}, n) reactions could give a choice of sub-threshold or hard-spectrum neutrons at yields ranging from 10{sup 4}/s to more than 10{sup 8}s. The SRNS would provide improved capabilities for (1) simultaneous or alternating interrogation with fast and slow neutrons, (2) detection of the first few seconds of delayed neutrons, (3) measurements in the presence of high neutron and/or gamma background, and (4) inspection of heterogeneous materials. When the neutrons are switched off, the source would be portable with vastly reduced shielding. Proof-of-concept with a single switchable plate has been established under laboratory conditions.

DeVolpi, A.

1995-07-01T23:59:59.000Z

Note: This page contains sample records for the topic "neutron powder diffraction" 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

Instrument and method for focusing x rays, gamma rays, and neutrons  

DOE Patents (OSTI)

A crystal-diffraction instrument or diffraction-grating instrument is described with an improved crystalline structure or grating spacing structure having a face for receiving a beam of photons or neutrons and diffraction planar spacing or grating spacing along that face with the spacing increasing progressively along the face to provide a decreasing Bragg diffraction angle for a monochromatic radiation and thereby increasing the usable area and acceptance angle. The increased planar spacing for the diffraction crystal is provided by the use of a temperature differential across the line structures with different compositions, by an individual crystalline structure with a varying composition and thereby a changing planar spacing along its face, and by combinations of these techniques. The increased diffraction grating element spacing is generated during the fabrication of the diffraction grating by controlling the cutting tool that is cutting the grooves or controlling the laser beam, electron beam, or ion beam that is exposing the resist layer, etc. It is also possible to vary this variation in grating spacing by applying a thermal gradient to the diffraction grating in much the same manner as is done in the crystal-diffraction case.

Smither, R.K.

1982-03-25T23:59:59.000Z

462

The Diffraction of Kelvin Waves and Bores at Coastal Bends  

Science Conference Proceedings (OSTI)

Bends in coastal mountain ranges may diffract propagating atmospheric Kelvin waves and trapped coastal currents. Analytic solutions exist for the diffraction of both linear Kelvin waves and linear nonrotating gravity waves. Within the context of ...

William C. Skamarock; Joseph B. Klemp; Richard Rotunno

1996-05-01T23:59:59.000Z

463

Gas atomized precursor alloy powder for oxide dispersion strengthened ferritic stainless steel  

Science Conference Proceedings (OSTI)

Gas atomization reaction synthesis (GARS) was employed as a simplified method for producing precursor powders for oxide dispersion strengthened (ODS) ferritic stainless steels (e.g., Fe-Cr-Y-(Ti,Hf)-O), departing from the conventional mechanical alloying (MA) process. During GARS processing a reactive atomization gas (i.e., Ar-O{sub 2}) was used to oxidize the powder surfaces during primary break-up and rapid solidification of the molten alloy. This resulted in envelopment of the powders by an ultra-thin (t < 150 nm) metastable Cr-enriched oxide layer that was used as a vehicle for solid-state transport of O into the consolidated microstructure. In an attempt to better understand the kinetics of this GARS reaction, theoretical cooling curves for the atomized droplets were calculated and used to establish an oxidation model for this process. Subsequent elevated temperature heat treatments, which were derived from Rhines pack measurements using an internal oxidation model, were used to promote thermodynamically driven O exchange reactions between trapped films of the initial Cr-enriched surface oxide and internal Y-enriched intermetallic precipitates. This novel microstructural evolution process resulted in the successful formation of nano-metric Y-enriched dispersoids, as confirmed using high energy X-ray diffraction and transmission electron microscopy (TEM), equivalent to conventional ODS alloys from MA powders. The thermal stability of these Y-enriched dispersoids was evaluated using high temperature (1200C) annealing treatments ranging from 2.5 to 1,000 hrs of exposure. In a further departure from current ODS practice, replacing Ti with additions of Hf appeared to improve the Y-enriched dispersoid thermal stability by means of crystal structure modification. Additionally, the spatial distribution of the dispersoids was found to depend strongly on the original rapidly solidified microstructure. To exploit this, ODS microstructures were engineered from different powder particle size ranges, illustrating microstructural control as a function of particle solidification rate. The consolidation of ultra-fine powders (dia. ? 5?m) resulted in a significant reduction in dispersoid size and spacing, consistent with initial scanning electron microscopy studies on as-atomized cross-sectioned particles that suggested that these powders solidified above the threshold velocity to effectively solute trap Y within the ?-(Fe,Cr) matrix. Interestingly, when the solidification velocity as a function of particle size was extracted from the aforementioned theoretical particle cooling curves, it could be offered as supporting evidence for these microstructure observations. Thermal-mechanical treatments also were used to create and evaluate the stability of a dislocation substructure within these alloys, using microhardness and TEM analysis of the alloy sub-grain and grain structure. Moreover, elevated temperature tensile tests up to 800C were used to assess the initial mechanical strength of the ODS microstructure.

Rieken, Joel

2011-12-13T23:59:59.000Z

464

PLUTONIUM-HYDROGEN REACTION PRODUCT, METHOD OF PREPARING SAME AND PLUTONIUM POWDER THEREFROM  

DOE Patents (OSTI)

A process is described for forming plutonlum hydride powder by reacting hydrogen with massive plutonium metal at room temperature and the product obtained. The plutonium hydride powder can be converted to plutonium powder by heating to above 200 deg C.

Fried, S.; Baumbach, H.L.

1959-12-01T23:59:59.000Z

465

CoNiFe Alloy Powder Synthesis by High Energy Milling  

Science Conference Proceedings (OSTI)

CoNiFe alloy powder was synthesized by high energy milling of mixtures of Co, Ni and Fe powder as a bulk processing method for producing powder. A milling...

466

Hypernuclear Physics for Neutron Stars  

E-Print Network (OSTI)

The role of hypernuclear physics for the physics of neutron stars is delineated. Hypernuclear potentials in dense matter control the hyperon composition of dense neutron star matter. The three-body interactions of nucleons and hyperons determine the stiffness of the neutron star equation of state and thereby the maximum neutron star mass. Two-body hyperon-nucleon and hyperon-hyperon interactions give rise to hyperon pairing which exponentially suppresses cooling of neutron stars via the direct hyperon URCA processes. Non-mesonic weak reactions with hyperons in dense neutron star matter govern the gravitational wave emissions due to the r-mode instability of rotating neutron stars.

Jurgen Schaffner-Bielich

2008-01-24T23:59:59.000Z

467

Phase-shifting point diffraction interferometer grating designs  

DOE Patents (OSTI)

In a phase-shifting point diffraction interferometer, by sending the zeroth-order diffraction to the reference pinhole of the mask and the first-order diffraction to the test beam window of the mask, the test and reference beam intensities can be balanced and the fringe contrast improved. Additionally, using a duty cycle of the diffraction grating other than 50%, the fringe contrast can also be improved.

Naulleau, Patrick (Oakland, CA); Goldberg, Kenneth Alan (Berkeley, CA); Tejnil, Edita (San Carlos, CA)

2001-01-01T23:59:59.000Z

468

THE MICROPOROSITY OF BERYLLIUM OXIDE POWDER  

SciTech Connect

Beryllium oxide produced in the thermal decomposition of complex compounds is characterized by the low bulk weight and the inferior pressing properties. An investigation was made of the causes of the deterioration of the pressing properties of beryllium oxide. Beryllium oxide with a bulk weight of 0.107 g/cm/sup 3/ is pressed into briquets ai a pressure of 1 io 1.5 t/cm/sup 2/. It was found thai the amount of pressure applied does not change the properties of the pressed articles. The microporosity of the beryllium oxide sample was investigated as dependent on the sintering temperature. The main cause for the inferior pressing and the low bulk weight of beryllium oxide powder is the high microporosily of ihe sample. An increase of ihe densiiy of beryllium oxide does not only bring about a decrease of the microporosity bui also a change of the grain size. The properties of thue initial beryllium were investigated by means of a small-angle x-ray analysis. (TCO)

Astrakhantsev, S.M.; Umanskii, Ya.S.

1958-01-01T23:59:59.000Z

469

Switchable radioactive neutron source device  

DOE Patents (OSTI)

This invention is a switchable neutron generating apparatus comprised of a pair of plates, the first plate having an alpha emitter section on it and the second plate having a target material portion on it which generates neutrons when its nuclei absorb an alpha particle. In operation, the alpha portion of the first plate is aligned with the neutron portion of the second plate to produce neutrons and brought out of alignment to cease production of neutrons. 3 figs.

Stanford, G.S.; Rhodes, E.A.; Devolpi, A.; Boyar, R.E.

1987-11-06T23:59:59.000Z

470

Diffractive Pion Dissociation into ? ? ? + ? ? ? + ? ? at COMPASS  

Science Conference Proceedings (OSTI)

At the COMPASS experiment a sample of ?380000 exclusive events of diffractive pion dissociation on a lead target into a ? ? ? + ? ? ? + ? ? final state has been recorded in 2004. The 5? invariant mass spectrum shows a momentum transfer dependent structure peaking around 1.8? GeV / c 2 . In the (4?) 0 subsystem there is a clear signal for the f 1 (1285) resonance decaying into 4 pions. In this note we describe the data sample and explore the physics potential of this final state.

S. Neubert; The COMPASS collaboration

2010-01-01T23:59:59.000Z

471

RECENT ADVANCES IN THE POWDER METALLURGY OF URANIUM CARBIDE  

SciTech Connect

uranium carbide, uranium metal is converted to uranium hydride powder and then carburized using propane gas. The carbide particles are irregular, of a relatively uniform size, and highly pyrophoric. Paraffin, camphor, cetyl alcohol, beeswax, and carbowax are used as lubricants and binders for compacting uranium carbide powder. Sintering studies were conducted for various times and temperatures, primarily in vacuum. An investigation is in progress to evaluate the effect of carbon content on the properties and irradiation stability of uranium carbide. It is shown that the powder metallurgy technique achieves a product wfth reasonably good density and apparentiy adequate properties for reactor utilization. (M.C.G.)

Kalish, H.S.

1962-10-31T23:59:59.000Z

472

Atomizing apparatus for making polymer and metal powders and whiskers  

DOE Patents (OSTI)

Method for making polymer particulates, such as spherical powder and whiskers, by melting a polymer material under conditions to avoid thermal degradation of the polymer material, atomizing the melt using gas jet means in a manner to form atomized droplets, and cooling the droplets to form polymer particulates, which are collected for further processing. Atomization parameters can be controlled to produce polymer particulates with controlled particle shape, particle size, and particle size distribution. For example, atomization parameters can be controlled to produce spherical polymer powders, polymer whiskers, and combinations of spherical powders and whiskers. Atomizing apparatus also is provided for atoomizing polymer and metallic materials.

Otaigbe, Joshua U. (Ames, IA); McAvoy, Jon M. (Moline, IL); Anderson, Iver E. (Ames, IA); Ting, Jason (Ames, IA); Mi, Jia (Pittsburgh, PA); Terpstra, Robert (Ames, IA)

2003-03-18T23:59:59.000Z

473

Sequence stratigraphy of the lower Pierre Shale in southern Powder River Basin, Wyoming, USA.  

E-Print Network (OSTI)

??Powder River Basin is one of the biggest interior sedimentary basins in the Rocky Mountain region. The Upper Cretaceous section of the southern Powder River (more)

Kaykun, Armagan

2013-01-01T23:59:59.000Z

474

Industry - ORNL Neutron Sciences  

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

PartTec PartTec ORNL, PartTec Inc. Licensing Agreement ORNL and PartTec sign licensing agreement (Front) ORNL Deputy Director for Science & Technology Thomas Zacharia and PartTec CEO Herschel Workman. (Back) Bruce Hannan (SNS), PartTec production manager Craig Kline, Rick Riedel (SNS), Jason Hodges (SNS) and Ron Cooper (SNS). The SNS guys were on the development team. Representatives from Oak Ridge National Laboratory and PartTec, an Indiana-based firm, formally signed a licensing agreement Thursday, Aug. 12, to market an advanced neutron detector system developed for the Spallation Neutron Source. The Shifting Scintillator Neutron Detector can determine the time and position of captured neutrons, which enables researchers to obtain very accurate time-of-flight measurements.

475

Education | ORNL Neutron Sciences  

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

Education banner Education banner Sunil Sinha A Chat with Sunil Sinha, Distinguished Professor of Physics at the University of California-San Diego and speaker at the recent CNMS-SNS Research Forum more... The purpose of the Spallation Neutron Source and the High Flux Isotope Reactor is to facilitate neutron scattering as an integral tool for scientific research and technological development across many scientific and engineering domains within the scientific, academic,and industrial communities. Coupled with this role is a recognized need to inspire, educate, and facilitate the next generation of users and hence foster enhanced use of the unique neutron scattering facilities at ORNL. This is the central theme of the education activities within the Neutron Sciences Directorate (NScD).

476

ORNL Neutron Sciences Instruments  

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

Instruments banner Instruments banner ORNL Neutron Sciences Instruments SNS and HFIR provide researchers with two complementary world-class suites of neutron scattering instruments and beam lines. All the instruments are supported by a variety of sample environments and data analysis and visualization capabilities. Before submitting a proposal for a specific instrument, please contact the appropriate instrument scientist to make sure your research is feasible for that instrument. Instruments Currently Available to Users SNS Beam Line Instrument Name HFIR Beam Line Instrument Name 1B NOMAD Nanoscale-Ordered Materials Diffractometer CG-1 Development Beam Line 2 BASIS Backscattering Spectrometer CG-1D IMAGING Neutron Imaging Prototype Facility 3 SNAP Spallation Neutrons and Pressure Diffractometer CG-2 GP-SANS

477

Awards | Neutron Science | ORNL  

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

| Neutron Science | News and Awards | Awards SHARE Awards for Excellence 1-2 of 2 Results ORNL team wins R&D 100 award for wavelength-shifting scintillator detector January...

478

Personnel neutron dosimetry  

Science Conference Proceedings (OSTI)

This edited transcript of a presentation on personnel neutron discusses the accuracy of present dosimetry practices, requirements, calibration, dosemeter types, quality factors, operational problems, and dosimetry for a criticality accident. 32 figs. (ACR)

Hankins, D.

1982-04-01T23:59:59.000Z

479

Neutron personnel dosimetry  

Science Conference Proceedings (OSTI)

The current state-of-the-art in neutron personnel dosimetry is reviewed. Topics covered include dosimetry needs and alternatives, current dosimetry approaches, personnel monitoring devices, calibration strategies, and future developments. (ACR)

Griffith, R.V.

1981-06-16T23:59:59.000Z

480

Neutron Scattering Science User ...  

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

Proposals for beam time at Oak Ridge National Laboratory's High Flux Isotope Reactor (HFIR) and Spallation Neutron Source (SNS) will be accepted via the web-based proposal system...

Note: This page contains sample records for the topic "neutron powder diffraction" 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.


481

ORNL Neutron Sciences Users  

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

SHUG banner SNS-HFIR User Group The SNS-HFIR User Group (SHUG) consists of all persons interested in using the neutron scattering facilities at Oak Ridge. It provides input to the...

482

Neutron scattering study of MnSi proving no exchange hole  

SciTech Connect

Neutron scattering experiments have been performed in MnSi below T/sub c/ with the double-axis powder scattering technique using unpolarized neutrons, and also with the polarization analysis technique. The magnetic scattering intensity has not shown any anomaly around q = 0.5 A/sup -1/, in contrast to the previous results of Ziebeck et al. who found a large intensity peak at this momentum transfer. Thus the hypothesis of Ziebeck et al. of observing an Exchange Hole is excluded.

Uemura, Y.J.; Majkrzak, C.F.; Shirane, G.; Ishikawa, Y.

1983-01-01T23:59:59.000Z

483

Combined Rietveld Analysis of X-Ray and Neutron Diffraction Data ...  

Science Conference Proceedings (OSTI)

Currently, indium-based oxides dominate the market for flat-panel displays. Indium is a toxic ... Oxygen Transport Investigation on Infiltrated SOFC Cathode.

484

NEUTRON FLUX INTENSITY DETECTION  

DOE Patents (OSTI)

A method of measuring the instantaneous intensity of neutron flux in the core of a nuclear reactor is described. A target gas capable of being transmuted by neutron bombardment to a product having a resonance absorption line nt a particular microwave frequency is passed through the core of the reactor. Frequency-modulated microwave energy is passed through the target gas and the attenuation of the energy due to the formation of the transmuted product is measured. (AEC)

Russell, J.T.

1964-04-21T23:59:59.000Z

485

ORNL Neutron Sciences Directorate Executive Office  

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

Neutron Sciences Directorate Executive Office Kelly Beierschmitt ORNL Associate Laboratory Director for Neutron Sciences Kelly Beierschmitt. The Neutron Sciences Directorate (NScD)...

486

Facilities and Capabilities | Neutron Science | ORNL  

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

Isotope Reactor and the Spallation Neutron Source. The continuous neutron source at HFIR and the pulsed neutron source at SNS complement each other well and, along with their...

487

Science Education Programs | Neutron Science | ORNL  

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

What are Neutrons Why Research with Neutrons Graduate & Post-doctoral Programs Student & Teacher Programs Science Forum Neutron Scattering Tutorials Kids' Corner News and Awards...

488

Polarized neutrons in RHIC  

Science Conference Proceedings (OSTI)

There does not appear to be any obvious way to accelerate neutrons, polarized or otherwise, to high energies by themselves. To investigate the behavior of polarized neutrons the authors therefore have to obtain them by accelerating them as components of heavier nuclei, and then sorting out the contribution of the neutrons in the analysis of the reactions produced by the heavy ion beams. The best neutron carriers for this purpose are probably {sup 3}He nuclei and deuterons. A polarized deuteron is primarily a combination of a proton and a neutron with their spins pointing in the same direction; in the {sup 3}He nucleus the spins of the two protons are opposite and the net spin (and magnetic moment) is almost the same as that of a free neutron. Polarized ions other than protons may be accelerated, stored and collided in a ring such as RHIC provided the techniques proposed for polarized proton operation can be adapted (or replaced by other strategies) for these ions. This paper discusses techniques for accelerating polarized {sup 3}He nuclei and deuterons.

Courant, E.D.

1998-04-20T23:59:59.000Z

489

Optical-diffraction method for determining crystal orientation  

DOE Patents (OSTI)

Disclosed is an optical diffraction technique for characterizing the three-dimensional orientation of a crystal sample. An arbitrary surface of the crystal sample is texture etched so as to generate a pseudo-periodic diffraction grating on the surface. A laser light beam is then directed onto the etched surface, and the reflected light forms a farfield diffraction pattern in reflection. Parameters of the diffraction pattern, such as the geometry and angular dispersion of the diffracted beam are then related to grating shape of the etched surface which is in turn related to crystal orientation. This technique may be used for examining polycrystalline silicon for use in solar cells.

Sopori, B.L.

1982-05-07T23:59:59.000Z

490

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

491

LOW TEMPERATURE X-RAY DIFFRACTION STUDIES OF NATURAL GAS HYDRATE SAMPLES FROM THE GULF OF MEXICO  

SciTech Connect

Clathrate hydrates of methane and other small alkanes occur widespread terrestrially in marine sediments of the continental margins and in permafrost sediments of the arctic. Quantitative study of natural clathrate hydrates is hampered by the difficulty in obtaining pristine samples, particularly from submarine environments. Bringing samples of clathrate hydrate from the seafloor at depths without compromising their integrity is not trivial. Most physical property measurements are based on studies of laboratory-synthesized samples. Here we report X-ray powder diffraction measurements of a natural gas hydrate sample from the Green Canyon, Gulf of Mexico. The first data were collected in 2002 and revealed ice and structure II gas hydrate. In the subsequent time the sample has been stored in liquid nitrogen. More recent X-ray powder diffraction data have been collected as functions of temperature and time. This new data indicates that the larger sample is heterogeneous in ice content and shows that the amount of sII hydrate decreases with increasing temperature and time as expected. However, the dissociation rate is higher at lower temperatures and earlier in the experiment.

Rawn, Claudia J [ORNL; Sassen, Roger [Texas A& M University; Ulrich, Shannon M [ORNL; Phelps, Tommy Joe [ORNL; Chakoumakos, Bryan C [ORNL; Payzant, E Andrew [ORNL

2008-01-01T23:59:59.000Z

492

Zro 2 Composite Powder from Zro 2 - Programmaster.org  

Science Conference Proceedings (OSTI)

Presentation Title, Carbothermal Production of Zrb2-Zro2 Composite Powder from ... Nut Shell Fiber and Electron-Beam Irradiation in Thermo-Mechanical Properties of HDPE ... Evaluation of Polypropylene/Saw Dust Composites Prepared with...

493

Process for synthesizing compounds from elemental powders and product  

DOE Patents (OSTI)

A process for synthesizing intermetallic compounds from elemental powders is described. The elemental powders are initially combined in a ratio which approximates the stoichiometric composition of the intermetallic compound. The mixed powders are then formed into a compact which is heat treated at a controlled rate of heating such that an exothermic reaction between the elements is initiated. The heat treatment may be performed under controlled conditions ranging from a vacuum (pressureless sintering) to compression (hot pressing) to produce a desired densification of the intermetallic compound. In a preferred form of the invention, elemental powders of Fe and Al are combined to form aluminide compounds of Fe[sub 3] Al and FeAl. 25 figures.

Rabin, B.H.; Wright, R.N.

1993-12-14T23:59:59.000Z

494

Dynamic in-situ X-ray Diffraction of Catalyzed Alanates  

DOE Green Energy (OSTI)

The discovery that hydrogen can be reversible absorbed and desorbed from NaAlH{sub 4} by the addition of catalysts has created an entirely new prospect for lightweight hydrogen storage. NaAlH{sub 4} releases hydrogen through the following set of decomposition reactions: NaAlH{sub 4} {r_arrow} 1/3({alpha}-Na{sub 3}AlH{sub 6}) + 2/3Al + H{sub 2} {r_arrow} NaH + Al + 3/2H{sub 2}. These decomposition reactions as well as the reverse recombination reactions were directly observed using time-resolved in-situ x-ray powder diffraction. These measurements were performed under conditions similar to those found in PEM fuel cell operations (hydrogen absorption: 50--70 C, 10--15 bar Hz, hydrogen resorption: 80--110 C, 5--100 mbar H{sub 2}). Catalyst doping was found to dramatically improve kinetics under these conditions. In this study, the alanate was doped with a catalyst by dry ball-milling NaAlH{sub 4} with 2 mol.% solid TiCl{sub 3}. X-ray diffraction clearly showed that TiCl{sub 3} reacts with NaAlH{sub 4} to form NaCl during the doping process. Partial desorption of NaAlH{sub 4} was even observed to occur during the catalyst doping process.

Gross, K.J.; Sandrock, G.; Thomas, G.J.

2000-11-01T23:59:59.000Z

495

Fast neutron dosimeter using Cooled Optically Stimulated Luminescence (COSL)  

SciTech Connect

Data is presented that demonstrates the concept of a fast neutron dosimeter using Cooled Optically Stimulated Luminescence. CaF{sub 2}:Mn powder, compounded with polyethylene, was injection molded and pressed into 0.1-cm-thick sheets. The sheets were then cut to form dosimeters with dimensions, 1.25 cm by 1.25 cm. After a laser anneal, the dosimeters were exposed to various amounts (from 10 mSv to 100 mSv) of fast {sup 252}Cf neutrons. The exposed dosimeters were cooled to liquid nitrogen temperature, stimulated with laser light, and then allowed to warm up to room temperature whereupon the dose dependent luminescence was recorded with a photon counting system. When the control and gamma components were subtracted from the {sup 252}Cf response, a dose-dependent neutron response was observed. The design, construction, and preliminary performance of an automated system for the dose interrogation of individual CaF{sub 2}:Mn grains within the polyethylene matrix will also be discussed. The system uses a small CO{sub 2} laser to heat areas of the cooled dosimeter to room temperature. If the readout of very small grain within the plastic matrix is successful, it will enhance the neutron to gamma response of the dosimeter.

Eschbach, P.A.; Miller, S.D.

1991-10-01T23:59:59.000Z

496

Usage Of Polyacetal Powders As Laser Ablation Propulsion Propellants  

Science Conference Proceedings (OSTI)

We examined impulse characteristics of polyoxymeythylene (POM) powders under irradiation by a TEA (Transversely-Excited at Atmospheric pressure)CO{sub 2} laser pulse. The impulse performance exhibited large scatter due to splashing particles. When the powder was hydraulically compacted to form a disk, the momentum coupling coefficient became comparable with that for bulk material, but the mass consumption was increased by several times.

Sasoh, Akihiro; Ogita, Naoya [Department of Aerospace Engineering, Nagoya University, Furo-cho, Chikusa-ku, Nagoya 464-8603 (Japan); Sinko, John E. [Micro-Nano Global Center of Excellence, Nagoya University, Furo-cho, Chikusa-ku, Nagoya 464-8603 (Japan)

2010-05-06T23:59:59.000Z

497

Manual Plasma Welding (PTAW) Evaluation with Powder Hardfacing Alloys  

Science Conference Proceedings (OSTI)

Repair practices for hardfacing alloys using gas tungsten arc welding (GTAW) and shielded metal arc welding (SMAW) have been evaluated in the past on hardfacing applied with various automated welding processes. Accessibility often limits the use of these welding processes in manual repair applications. Recent developments in plasma transfer arc welding (PTAW) powder welding systems have prompted evaluations of manual repair practices for hardfacing materials. The PTAW powder welding process feeds the fil...

2001-12-18T23:59:59.000Z

498

Supercritical fluid molecular spray thin films and fine powders  

DOE Patents (OSTI)

Solid films are deposited, or fine powders formed, by dissolving a solid material into a supercritical fluid solution at an elevated pressure and then rapidly expanding the solution through a short orifice into a region of relatively low pressure. This produces a molecular spray which is directed against a substrate to deposit a solid thin film thereon, or discharged into a collection chamber to collect a fine powder. The solvent is vaporized and pumped away. Solution pressure is varied to determine, together with flow rate, the rate of deposition and to control in part whether a film or powder is produced and the granularity of each. Solution temperature is varied in relation to formation of a two-phase system during expansion to control porosity of the film or powder. A wide variety of film textures and powder shapes are produced of both organic and inorganic compounds. Films are produced with regular textural feature dimensions of 1.0-2.0 .mu.m down to a range of 0.01 to 0.1 .mu.m. Powders are formed in very narrow size distributions, with average sizes in the range of 0.02 to 5 .mu.m.

Smith, Richard D. (Richland, WA)

1988-01-01T23:59:59.000Z

499

Stability of captopril in powder papers under three storage conditions  

Science Conference Proceedings (OSTI)

The stability of captopril in powder papers under three different storage conditions was determined. Captopril 12.5-mg tablets were triturated with lactose to a final concentration of 2 mg of captopril in 100 mg of powder. A total of 240 powder papers were prepared and stored in class A prescription vials (80 papers), 002G plastic zip-lock bags (80 papers), and Moisture Proof Barrier Bags (80 papers). Immediately after preparation and at 1, 2, 3, 4, 8, 12, and 24 weeks of storage at room temperature, powder papers under each storage condition were reweighed and the contents were assayed for captopril concentration by a stability-indicating high-performance liquid chromatographic method. More than 90% of the initial captopril concentration was retained under all storage conditions during the first 12 weeks of the study. Captopril disulfide, a degradation product, was detected in one sample stored in a plastic zip-lock bag at 24 weeks. Captopril was stable for the entire 24-week period in powder papers stored in either the class A prescription vial or the Moisture Proof Barrier Bag. Captopril in powder papers is stable for at least 12 weeks when stored at room temperature under all three storage conditions.

Taketomo, C.K.; Chu, S.A.; Cheng, M.H.; Corpuz, R.P. (Childrens Hospital, Los Angeles, CA (USA))

1990-08-01T23:59:59.000Z

500

Dr. Xiaoping Wang | ORNL Neutron Sciences  

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

Home › Contact Us › CV Home › Contact Us › CV Dr. Xiaoping Wang Instrument Scientist TOPAZ BL-12 Dr. Xiaoping Wang received his Ph.D. degree in inorganic chemistry from Texas A&M University in 1998, where he did his graduate work with Professor F. Albert Cotton. He then undertook postdoctoral research in neutron crystallography at Argonne National Laboratory. He was the director for crystallographic computing in the Laboratory for Molecular Structure and Bonding at Texas A&M University from December 2001 to May 2006; the director of X-Ray Diffraction Laboratory at University of North Texas from June 2006 to July 2008, and has been appointed as adjunct professor in the chemistry department. Dr. Wang is currently an instrument scientist co-responsible for the TOPAZ single crystal diffractometer (SNS