Sample records for zirconium 97

  1. Zirconium

    USGS Publications Warehouse

    Bedinger, G.M.

    2013-01-01

    Zirconium is the 20th most abundant element in the Earth’s crust. It occurs in a variety of rock types and geologic environments but most often in igneous rocks in the form of zircon (ZrSiO4). Zircon is recovered as a coproduct of the mining and processing of heavy mineral sands for the titanium minerals ilmenite and rutile. The sands are formed by the weathering and erosion of rock containing zircon and titanium heavy minerals and their subsequent concentration in sedimentary systems, particularly in coastal environments. A small quantity of zirconium, less than 10 kt/a (11,000 stpy), compared with total world production of 1.4 Mt (1.5 million st) in 2012, was derived from the mineral baddeleyite (ZrO2), produced from a single source in Kovdor, Russia.

  2. Studies in zirconium oxidation

    NASA Technical Reports Server (NTRS)

    Draley, J. E.; Drunen, C. J.; Levitan, J.

    1968-01-01

    Study provides insight into the oxidation mechanism of zirconium by combining electrical measurements with oxidation data. The measurement of electrical potential across growing scale on zirconium and the determination of conventional weight-change oxidation data were carried out at 550, 700, and 800 degrees C.

  3. Electroless deposition process for zirconium and zirconium alloys

    DOEpatents

    Donaghy, Robert E. (Wilmington, NC); Sherman, Anna H. (Wilmington, NC)

    1981-01-01

    A method is disclosed for preventing stress corrosion cracking or metal embrittlement of a zirconium or zirconium alloy container that is to be coated on the inside surface with a layer of a metal such as copper, a copper alloy, nickel, or iron and used for holding nuclear fuel material as a nuclear fuel element. The zirconium material is etched in an etchant solution, desmutted mechanically or ultrasonically, oxidized to form an oxide coating on the zirconium, cleaned in an aqueous alkaline cleaning solution, activated for electroless deposition of a metal layer and contacted with an electroless metal plating solution. This method provides a boundary layer of zirconium oxide between the zirconium container and the metal layer.

  4. Electroless deposition process for zirconium and zirconium alloys

    DOEpatents

    Donaghy, R. E.; Sherman, A. H.

    1981-08-18

    A method is disclosed for preventing stress corrosion cracking or metal embrittlement of a zirconium or zirconium alloy container that is to be coated on the inside surface with a layer of a metal such as copper, a copper alloy, nickel, or iron and used for holding nuclear fuel material as a nuclear fuel element. The zirconium material is etched in an etchant solution, desmutted mechanically or ultrasonically, oxidized to form an oxide coating on the zirconium, cleaned in an aqueous alkaline cleaning solution, activated for electroless deposition of a metal layer and contacted with an electroless metal plating solution. This method provides a boundary layer of zirconium oxide between the zirconium container and the metal layer. 1 fig.

  5. Surface reactions of tetraneopentyl zirconium on zirconium carbide thin films

    Microsoft Academic Search

    John E. Parmeter; D. C. Smith; M. D. Healy

    1994-01-01

    Interest has arisen recently in the use of metal alkyl compounds as precursors in the chemical vapor deposition of metal carbides. This paper presents results of a study of the surface chemistry of one such precursor, tetraneopentyl zirconium (ZrNp[sub 4]), on zirconium carbide thin films. Decomposition of the precursor leads to the desorption of both methane and a larger hydrocarbon

  6. Organic derivatives of zirconium phosphate

    E-print Network

    Fine, Steven Beryl

    1980-01-01

    ORGANIC DERIVATIVES OF ZIRCONIUM PHOSPHATE A Thesis by STEVEN BERYL FINE Submitted to the Graduate College of Texas AAM University in partial fulfillment of the requirement for the degree of MASTER OF SCIENCE December 1980 Major Subject...: Chemistry ORGANIC DERIVATIVES OF ZIRCONIUM PHOSPHATE A Thesis by STEVEN BERYL FINE Approved as to style and content by: Dr. A raham Clearfield (c irman) Dr. Kurt Irgolic (member) 4~~@4 Dr. Martha Scott (member) Dr. C. S. Giam (department head...

  7. Ablation Resistant Zirconium and Hafnium Ceramics

    NASA Technical Reports Server (NTRS)

    Bull, Jeffrey (Inventor); White, Michael J. (Inventor); Kaufman, Larry (Inventor)

    1998-01-01

    High temperature ablation resistant ceramic composites have been made. These ceramics are composites of zirconium diboride and zirconium carbide with silicon carbide, hafnium diboride and hafnium carbide with silicon carbide and ceramic composites which contain mixed diborides and/or carbides of zirconium and hafnium. along with silicon carbide.

  8. Zirconium mobility in bauxites of Southern Brazil

    Microsoft Academic Search

    A. J. Melfi; F. Subies; D. Nahon; M. L. L. Formoso

    1996-01-01

    A geochemical study of the behaviour of zirconium in bauxites developed on alkaline rocks in southern Brazil is presented. Zirconium, generally considered as an immobile element during weathering, shows an important mobility conditioned to the original Zr bearing parent mineral. In the two areas (Poços de Caldas and Lages) zircon is rare and the zirconium bearing parent minerals are complex

  9. Surface reactions of tetraneopentyl zirconium on zirconium carbide thin films

    SciTech Connect

    Parmeter, J.E. (Department 1126, Sandia National Laboratories, Albuquerque, New Mexico 87185 (United States)); Smith, D.C.; Healy, M.D. (INC-1, MS-C346, Los Alamos National Laboratory, Los Alamos, New Mexico 87105 (United States))

    1994-07-01

    Interest has arisen recently in the use of metal alkyl compounds as precursors in the chemical vapor deposition of metal carbides. This paper presents results of a study of the surface chemistry of one such precursor, tetraneopentyl zirconium (ZrNp[sub 4]), on zirconium carbide thin films. Decomposition of the precursor leads to the desorption of both methane and a larger hydrocarbon species that is tentatively identified as neopentane. The desorption of large amounts of methane may help to explain the fact that ZrC films grown to date with this precursor are not stoichiometric but rather contain excess carbon.

  10. Zirconium and hafnium in meteorites

    NASA Technical Reports Server (NTRS)

    Ehmann, W. D.; Chyi, L. L.

    1974-01-01

    The abundances of zirconium and hafnium have been determined in nine stony meteorites by a new, precise neutron-activation technique. The Zr/Hf abundance ratios for the chondrites vary in a rather narrow range, consistent with previously published observations from our group. Replicate analyses of new, carefully selected clean interior samples of the Cl chondrite Orgueil yield mean zirconium and hafnium abundances of 5.2 and 0.10 ppm, respectively. These abundances are lower than we reported earlier for two Cl chondrite samples which we now suspect may have suffered contamination. The new Cl zirconium and hafnium abundances are in closer agreement with predictions based on theories of nucleosynthesis than the earlier data.

  11. ZIRCONIUM AND HAFNIUM--2001 86.1 ZIRCONIUM AND HAFNIUM

    E-print Network

    are contained in zircon at a ratio of about 50:1. Zircon is a coproduct or byproduct of the mining is processed to produce cubic zirconia, a diamond and colored gemstone simulant. Zirconium metal is used of domestic operations. In 2001, the two domestic zircon producers, which have three mining and processing

  12. ZIRCONIUM AND HAFNIUM--2000 87.1 ZIRCONIUM AND HAFNIUM

    E-print Network

    in zircon at a ratio of about 50 to 1. Zircon is a coproduct or byproduct of the mining and processing, a diamond and colored gemstone simulant. Zirconium metal is used in nuclear fuel cladding, chemical piping company proprietary data. Domestic production of zircon increased as a heavy-mineral sand mining operation

  13. ZIRCONIUM AND HAFNIUM--1999 86.1 ZIRCONIUM AND HAFNIUM

    E-print Network

    of the mining and processing of heavy-mineral sands for the titanium minerals, ilmenite and rutile, or tin to produce cubic zirconia, a diamond and colored gemstone simulant. Zirconium is used in nuclear fuel as a recently opened mining operation in Virginia continued to scale-up production. In 1999, production

  14. ZIRCONIUM AND HAFNIUM--1998 86.1 ZIRCONIUM AND HAFNIUM

    E-print Network

    of the mining and processing of heavy-mineral sands for the titanium minerals, ilmenite and rutile, or tin the diamond simulant, cubic zirconia. Zirconium is used in nuclear fuel cladding, chemical piping in corrosive. Domestic production of zircon increased as a new mine in Virginia came online. Production of milled zircon

  15. 40 CFR 721.9973 - Zirconium dichlorides (generic).

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ...2010-07-01 2010-07-01 false Zirconium dichlorides (generic). 721.9973...Chemical Substances § 721.9973 Zirconium dichlorides (generic). (a) Chemical...chemical substances identified generically as zirconium dichlorides (PMNs...

  16. Spectrophotometric titration of zirconium in siliceous materials.

    PubMed

    Sugawara, K F; Su, Y S; Strzegowski, W R

    An accurate and selective complexometric titration procedure based upon a spectrophotometrically detected end-point has been developed for the determination of zirconium in glasses, glass-ceramics and refractories. A p-bromomandelic acid separation step for zirconium imparts excellent selectivity to the procedure. The method is particularly important for the 1-5% concentration range where a simple, accurate and selective method for the determination of zirconium has been lacking. PMID:18962344

  17. Zirconium mobility in bauxites of Southern Brazil

    NASA Astrophysics Data System (ADS)

    Melfi, A. J.; Subies, F.; Nahon, D.; Formoso, M. L. L.

    1996-07-01

    A geochemical study of the behaviour of zirconium in bauxites developed on alkaline rocks in southern Brazil is presented. Zirconium, generally considered as an immobile element during weathering, shows an important mobility conditioned to the original Zr bearing parent mineral. In the two areas (Poços de Caldas and Lages) zircon is rare and the zirconium bearing parent minerals are complex weathered silicates as "giannettite", eudyalite, astrophyllite, etc. Since the first stages of weathering, zirconium is partially leached of from the bauxite profile and the remaining Zr is incorporated in secondary phases of the bauxite (amorphous ferric oxydes and aluminous goethite).

  18. Formation of zirconium metallic glass.

    PubMed

    Zhang, Jianzhong; Zhao, Yusheng

    2004-07-15

    Bulk metallic glasses are commonly produced by the rapid cooling of liquid alloys. They have emerged over the past decade as a novel class of materials, with attractive properties and technological promise. The bulk metallic glasses so far produced contain three or more component elements. These complex compositions are necessary to frustrate the crystallization of the liquid melt on cooling, but can also lead to phase separation, which is detrimental to the thermal and mechanical properties of metallic glasses. Here we report, using X-ray diffraction measurements, the formation of a bulk metallic glass from elemental zirconium at high static pressures and low temperatures (relative to its melting temperature at atmospheric pressure). Amorphous zirconium can be recovered at ambient conditions and demonstrates a superior thermal stability compared to amorphous alloys, which could lead to new high-temperature applications of amorphous metals. PMID:15254533

  19. Zirconium alloys in nuclear technology

    Microsoft Academic Search

    R. Krishnan; M. K. Asundi

    1981-01-01

    This paper describes the historical development of zirconium and its alloys as structural materials for nuclear reactors.\\u000a The various problems encountered in the early stages of the development of zircaloys and their performance in reactors operating\\u000a presently are described in detail. The development of Zr-2.5 % Nb alloys for pressure tube applications is discussed. The\\u000a paper concludes with a detailed

  20. Method for preparing hydrous zirconium oxide gels and spherules

    DOEpatents

    Collins, Jack L.

    2003-08-05

    Methods for preparing hydrous zirconium oxide spherules, hydrous zirconium oxide gels such as gel slabs, films, capillary and electrophoresis gels, zirconium monohydrogen phosphate spherules, hydrous zirconium oxide spherules having suspendable particles homogeneously embedded within to form a composite sorbent, zirconium monohydrogen phosphate spherules having suspendable particles of at least one different sorbent homogeneously embedded within to form a composite sorbent having a desired crystallinity, zirconium oxide spherules having suspendable particles homogeneously embedded within to form a composite, hydrous zirconium oxide fiber materials, zirconium oxide fiber materials, hydrous zirconium oxide fiber materials having suspendable particles homogeneously embedded within to form a composite, zirconium oxide fiber materials having suspendable particles homogeneously embedded within to form a composite and spherules of barium zirconate. The hydrous zirconium oxide spherules and gel forms prepared by the gel-sphere, internal gelation process are useful as inorganic ion exchangers, catalysts, getters and ceramics.

  1. Method of making crack-free zirconium hydride

    DOEpatents

    Sullivan, Richard W. (Denver, CO)

    1980-01-01

    Crack-free hydrides of zirconium and zirconium-uranium alloys are produced by alloying the zirconium or zirconium-uranium alloy with beryllium, or nickel, or beryllium and scandium, or nickel and scandium, or beryllium and nickel, or beryllium, nickel and scandium and thereafter hydriding.

  2. Penta­zirconium copper tribismuth

    PubMed Central

    Balinska, Agnieszka; Tarasiuk, Ivan; Pavlyuk, Volodymyr

    2013-01-01

    Penta­zirconium copper tribismuth, Zr5CuBi3, crystallizes in the hexa­gonal Hf5CuSn3 structure type. The asymmetric unit contains two Zr sites (site symmetries 3.2 and m2m), one Cu site (site symmetry 3.m) and one Bi site (site symmetry m2m). The environment of the Bi atoms is a tetra­gonal anti­prism with one added atom and a coordination number (CN) of 9. The polyhedron around the Zr1 atom is a defective cubo­octa­hedron with CN = 11. The bicapped hexa­gonal anti­prism (CN = 14) is typical for Zr2 atoms. The Cu atom is enclosed in a eight-vertex polyhedron (octa­hedron with two centered faces). The metallic type of bonding was indicated by an analysis of the inter­atomic distances and electronic structure calculation data. PMID:24109256

  3. STS-97 Crew Portrait

    NASA Technical Reports Server (NTRS)

    1999-01-01

    These five STS-97 crew members posed for a traditional portrait during training. On the front row, left to right, are astronauts Michael J. Bloomfield, pilot; Marc Garneau, mission specialist representing the Canadian Space Agency (CSA); and Brent W. Jett, Jr., commander. In the rear, wearing training versions of the extravehicular mobility unit (EMU) space suits, (left to right) are astronauts Carlos I. Noriega, and Joseph R. Tarner, both mission specialists. The primary objective of the STS-97 mission was the delivery, assembly, and activation of the U.S. electrical power system onboard the International Space Station (ISS). The electrical power system, which is built into a 73-meter (240-foot) long solar array structure consists of solar arrays, radiators, batteries, and electronics. The entire 15.4-metric ton (17-ton) package is called the P6 Integrated Truss Segment and is the heaviest and largest element yet delivered to the station aboard a space shuttle. The electrical system will eventually provide the power necessary for the first ISS crews to live and work in the U.S. segment. The STS-97 crew of five launched aboard the Space Shuttle Orbiter Endeavor on November 30, 2000 for an 11 day mission.

  4. Synthesis of zirconium oxide nanoparticle by sol-gel technique

    SciTech Connect

    Lim, H. S.; Ahmad, A.; Hamzah, H. [School of Chemical Science and Food Technology, Faculty of Science and Technology, National University of Malaysia, 43600 Bangi (Malaysia)

    2013-11-27

    Zirconium oxide nanoparticle is synthesized using sol-gel technique. Various mole ratio of ammonia solution and nitric acid relative to zirconium propoxide is added in the reaction to study the effect on the crystallinity and particle size on zirconium oxide particle. Zirconium oxide synthesized with nitric acid have the smallest particle size under FESEM image and show the increasing formation of crystalline tetragonal phase under XRD diffractogram.

  5. XPS Studies of the Stability of a Zirconium Carbide Film in the Presence of Zirconium Oxide and Hydrogen

    NASA Astrophysics Data System (ADS)

    Wong, P. C.; Li, Y. S.; Mitchell, K. A. R.

    X-ray photoelectron spectroscopy (XPS) has been used to study the interfacial chemistries of a 65-Å film prepared by depositing zirconium in an oxidizing environment onto a methane-pretreated 11-Å thick zirconium oxide film, which initially was deposited onto a gold substrate. The second metal deposition results in an outermost region composed of a mixed zirconium oxide, while below there is metallic zirconium followed by zirconium carbide and carbon on top of the first zirconium oxide film, which is itself in contact with the gold. The carbide component showed no changes on heating to 425°C, on treating with a hydrogen plasma at room temperature, or on heating the resulting film to 425°C. The oxide layers do show characteristic changes, and this also contrasts with earlier observations for a zirconium sulphide film. The zirconium carbide Zr3d5/2 component has a binding energy of 180.6 eV.

  6. TECHNOLOGY OF MOLDING ZIRCONIUM OBJECTS

    Microsoft Academic Search

    G. P. Kalliga; V. A. Kolbasova; D. N. Poluboyarinov

    1962-01-01

    Processes for fabricating bodies from hydrous suspensions of 6% CaO ; stabilized crushed ZrOâ (97.55% ZrOâ with 1.15% TiOâ) were ; studied. It is shown that the best results are obtained with hydrochloric acid-; washed ZrOâ at 30% humidity and pH = 1.5 to 2. The density of the casting ; was 2.8 g\\/cm³, and the density of the finished

  7. Industrial applications of titanium and zirconium: Fourth volume

    SciTech Connect

    Young; Durham

    1986-01-01

    This book presents industrial applications of titanium and zirconium. This book also contains information on other reactive and refractory metals, including niobium, tantalum, and hafnium. There are fourteen (14) peer-reviewed papers which target these subjects: the applications of titanium; the applications of zirconium and other reactive metals and the technology of titanium and zirconium.

  8. The chemical vapor deposition of zirconium carbide onto ceramic substrates

    Microsoft Academic Search

    Glass John A Jr; Palmisiano Nick Jr; R. Edward Welsh

    1999-01-01

    Zirconium carbide is an attractive ceramic material due to its unique properties such as high melting point, good thermal conductivity, and chemical resistance. The controlled preparation of zirconium carbide films of superstoichiometric, stoichiometric, and substoichiometric compositions has been achieved utilizing zirconium tetrachloride and methane precursor gases in an atmospheric pressure high temperature chemical vapor deposition system.

  9. Synthesis of nanosized zirconium carbide by laser pyrolysis route

    Microsoft Academic Search

    L. Combemale; Y. Leconte; X. Portier; N. Herlin-Boime; C. Reynaud

    2009-01-01

    Nanosized zirconium carbide was obtained by carburization of tetragonal zirconia\\/free carbon nanocomposites synthesized by laser pyrolysis technique using zirconium butoxide as precursor and ethylene as sensitizer gas. To achieve the carboreduction, the powder had to be annealed at high temperature under Ar atmosphere to reduce the oxygen and form zirconium carbide (ZrC). Different temperatures were investigated for the heat treatment

  10. The chemical vapor deposition of zirconium carbide onto ceramic substrates

    SciTech Connect

    Glass, John A, Jr.; Palmisiano, Nick, Jr.; Welsh, R. Edward

    1999-07-01

    Zirconium carbide is an attractive ceramic material due to its unique properties such as high melting point, good thermal conductivity, and chemical resistance. The controlled preparation of zirconium carbide films of superstoichiometric, stoichiometric, and substoichiometric compositions has been achieved utilizing zirconium tetrachloride and methane precursor gases in an atmospheric pressure high temperature chemical vapor deposition system.

  11. Processing fissile material mixtures containing zirconium and/or carbon

    DOEpatents

    Johnson, Michael Ernest; Maloney, Martin David

    2013-07-02

    A method of processing spent TRIZO-coated nuclear fuel may include adding fluoride to complex zirconium present in a dissolved TRIZO-coated fuel. Complexing the zirconium with fluoride may reduce or eliminate the potential for zirconium to interfere with the extraction of uranium and/or transuranics from fission materials in the spent nuclear fuel.

  12. VACUUM PUMPING STUDY OF TITANIUM-ZIRCONIUM-VANADIUM THIN FILMS*

    E-print Network

    ERL 03-8 VACUUM PUMPING STUDY OF TITANIUM-ZIRCONIUM-VANADIUM THIN FILMS* Yulin Li# and Simon Ho performance of Titanium- Zirconium-Vanadium (TiZrV) NEG thin films was investigated to provide `engineering- Zirconium-Vanadium (TiZrV) NEG thin films, deposited on the interior of stainless steel (SST) pipes. The Ti

  13. Superconductivity in zirconium-rhodium alloys

    NASA Technical Reports Server (NTRS)

    Zegler, S. T.

    1969-01-01

    Metallographic studies and transition temperature measurements were made with isothermally annealed and water-quenched zirconium-rhodium alloys. The results clarify both the solid-state phase relations at the Zr-rich end of the Zr-Rh alloy system and the influence upon the superconducting transition temperature of structure and composition.

  14. Zirconium modified nickel-copper alloy

    NASA Technical Reports Server (NTRS)

    Whittenberger, J. D. (inventor)

    1977-01-01

    An improved material for use in a catalytic reactor which reduces nitrogen oxide from internal combustion engines is in the form of a zirconium-modified, precipitation-strengthened nickel-copper alloy. This material has a nominal composition of Ni-30 Cu-0.2 Zr and is characterized by improved high temperature mechanical properties.

  15. 40 CFR 471.90 - Applicability; description of the zirconium-hafnium forming subcategory.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... Applicability; description of the zirconium-hafnium forming subcategory. 471...METAL POWDERS POINT SOURCE CATEGORY Zirconium-Hafnium Forming Subcategory § 471.90 Applicability; description of the zirconium-hafnium forming subcategory....

  16. 40 CFR 421.330 - Applicability: Description of the primary zirconium and hafnium subcategory.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ...Applicability: Description of the primary zirconium and hafnium subcategory. 421.330...MANUFACTURING POINT SOURCE CATEGORY Primary Zirconium and Hafnium Subcategory § 421.330 Applicability: Description of the primary zirconium and hafnium subcategory. The...

  17. 40 CFR 721.10089 - Modified salicylic acid, zirconium complex (generic).

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ...2010-07-01 false Modified salicylic acid, zirconium complex (generic...Substances § 721.10089 Modified salicylic acid, zirconium complex (generic...identified generically as modified salicylic acid, zirconium complex (PMN...

  18. ZIRCONIUM AND HAFNIUM (Data in metric tons unless otherwise noted)

    E-print Network

    industries. Salient Statistics--United States: 2006 2007 2008 2009 2010 e Production, zircon (ZrO2 content) W W W W W Imports: Zirconium, ores and concentrates (ZrO2 content) 23,500 13,000 22,300 9,370 11: Zirconium ores and concentrates (ZrO2 content) 49,600 43,000 27,400 25,700 34,000 Zirconium, unwrought

  19. ZIRCONIUM AND HAFNIUM (Data in metric tons, unless otherwise noted)

    E-print Network

    other companies as well. Zirconia (ZrO2) was produced from zircon sand at plants in Alabama, New (ZrO2 content)1 W W W W W Imports: Zirconium, ores and concentrates (ZrO2 content) 60,800 60,100 40,600 58,200 38,600 Zirconium, alloys, waste and scrap (ZrO2 content) 884 836 929 1,210 1,400 Zirconium

  20. ZIRCONIUM AND HAFNIUM (Data in metric tons unless otherwise noted)

    E-print Network

    Imports: Zirconium, ores and concentrates (ZrO2 content) 9,370 14,900 17,200 16,700 6,500 Zirconium, unwrought, powder, and waste and scrap 5 8 10 23 10 Exports: Zirconium ores and concentrates (ZrO2 content, apparent (ZrO2 content) W W W W W Prices: Zircon, dollars per metric ton (gross weight): Domestic 1 830 860

  1. ZIRCONIUM AND HAFNIUM (Data in metric tons unless otherwise noted)

    E-print Network

    industries. Salient Statistics--United States: 2008 2009 2010 2011 2012 e Production, zircon (ZrO2 content) W W W W W Imports: Zirconium, ores and concentrates (ZrO2 content) 22,300 9,370 14,900 17,200 26 Exports: Zirconium ores and concentrates (ZrO2 content) 27,400 25,700 30,800 15,800 21,000 Zirconium

  2. ZIRCONIUM AND HAFNIUM (Data in metric tons unless otherwise noted)

    E-print Network

    industries. Salient Statistics--United States: 2007 2008 2009 2010 2011 e Production, zircon (ZrO2 content) W W W W W Imports: Zirconium, ores and concentrates (ZrO2 content) 13,000 22,300 9,370 14,900 13 Exports: Zirconium ores and concentrates (ZrO2 content) 43,000 27,400 25,700 30,800 15,500 Zirconium

  3. ZIRCONIUM AND HAFNIUM (Data in metric tons unless otherwise noted)

    E-print Network

    zirconium chemicals were produced by 10 other companies. Zirconia (ZrO2) was produced from zircon at plants Statistics--United States: 2002 2003 2004 2005 2006e Production, zircon (ZrO2 content) W W W W W Imports: Zirconium, ores and concentrates (ZrO2 content) 22,900 24,300 22,900 24,800 17,500 Zirconium, unwrought

  4. ZIRCONIUM AND HAFNIUM (Data in metric tons unless otherwise noted)

    E-print Network

    . Secondary zirconium chemicals were produced by 10 other companies. Zirconia (ZrO2) was produced from zircon 2003 2004 2005e Production, zircon (ZrO2 content) W W W W W Imports: Zirconium, ores and concentrates (ZrO2 content) 39,400 22,900 24,300 22,900 19,400 Zirconium, unwrought, powder, and waste and scrap

  5. HP Laboratories 5/22/97 Hiro:Documents:Giordano Beretta:Research:AIC97:aic97ohp.doc

    E-print Network

    Beretta, Giordano

    w w w HP Laboratories 5/22/97 Hiro:Documents:Giordano Beretta:Research:AIC97:aic97ohp.doc 0Encoding Beretta, Vasudev Bhaskaran, Konstantinos Konstantinides, Balas Natarajan Hewlett-Packard Laboratories http://www.hpl.hp.com/personal/Giordano_Beretta #12;w w w HP Laboratories 5/22/97 Hiro:Documents:Giordano Beretta:Research:AIC97:aic97ohp.doc 1The

  6. Polarographic determination of zirconium at trace level.

    PubMed

    Castrillejo, Y; Pardo, R; Barrado, E; Batanero, P S

    1985-05-01

    An indirect polarographic method has been developed for the determination of zirconium by formation of molybdozirconophosphoric acid, its extraction with MIBK or a mixture of diethyl ether and 1-butanol, stripping with alkali and measurement of the Mo(VI) by its catalytic effect on the polarographic reduction of hydrogen peroxide. Depending on the extradant, a detection limit of 2.5 or 8.9 mu/gl, can be achieved. PMID:18963868

  7. 47 CFR 97.505 - Element credit.

    Code of Federal Regulations, 2014 CFR

    2014-10-01

    ...2014-10-01 2014-10-01 false Element credit. 97.505 Section 97.505...Qualifying Examination Systems § 97.505 Element credit. (a) The administering...1) Amateur Extra Not applicable Elements 3 and 4. (2) Advanced;...

  8. Irradiation growth of zirconium single crystals

    NASA Astrophysics Data System (ADS)

    Carpenter, G. J. C.; Murgatroyd, R. A.; Rogerson, A.; Watters, J. F.

    1981-10-01

    Irradiation growth of zirconium single crystals has been studied during neutron irradiation at 353 K and 553 K at fluences up to 2× 10 25 n/m 2. The results may be summarized as follows: (a) there was an expansion parallel to the a-axis and a c-axis contraction; (b) the growth strains were small (~10 -4), (c) growth saturated at fluences less than ~5× 10 24 n/m 2, (d) the growth behaviour was only weakly dependent on temperature for the range studied, (e) there was a calculated volume increase of the same order as the growth strain, and (f) single crystals prepared from stock of iodide and zone-refined purity showed similar growth behaviour at 553 K. The a-axis expansion is attributed to the annihilation of an excess of interstitials at < a>-type dislocations and interstitial loops. The c-axis contraction may be caused by: (1) elastic relaxation around vacancies or small vacancy clusters, (2) non-linear elastic effects at the dislocation cores of small < a>-type loops, or (3) sub-microscopic vacancy loops with < c>-component Burgers vectors. Comparison with data from polycrystalline zirconium confirms that grain boundaries can play an important role in the irradiation growth of zirconium.

  9. High temperature behavior of zirconium germanates

    SciTech Connect

    Utkin, A.V., E-mail: utkinalex@hotmail.com [Institute of Solid State Chemistry and Mechanochemistry SB RAS, 18 Kutateladze st., Novosibirsk 630128 (Russian Federation); Baklanova, N.I. [Institute of Solid State Chemistry and Mechanochemistry SB RAS, 18 Kutateladze st., Novosibirsk 630128 (Russian Federation); Vasilyeva, I.G. [Nikolaev Institute of Inorganic Chemistry SB RAS, 3 Acad. Lavrentiev ave, Novosibirsk 630090 (Russian Federation)

    2013-05-15

    The high temperature behavior of zirconium germanates ZrGeO{sub 4} and Zr{sub 3}GeO{sub 8} up to 2300 °C has been studied using the original photoemission thermal analysis technique with the comprehensive physicochemical study of solid and gaseous intermediate and final products. The two-stage process of incongruent sublimation of GeO{sub 2} was established and the phase boundary of the homogeneity range for ZrGeO{sub 4} and Zr{sub 3}GeO{sub 8} were deduced from the thermal analysis, X-ray diffraction and Raman spectroscopy studies. A high tendency to sintering of the final ZrO{sub 2} product is discussed. - Graphical abstract: The decomposition of zirconium germanates leads to the formation of gaseous GeO{sub 2} and solid sintered ZrO{sub 2} and occurs via two stages with the formation of intermediate ZrO{sub 2}-rich solid solution. - Highlights: ?Thermal behavior of ZrGeO{sub 4} and Zr{sub 3}GeO{sub 8} was studied using the original thermal analysis technique in wide temperature range. ?The decomposition occurs via two stages with the formation of intermediate ZrO{sub 2}-rich solid solution. ?The decomposition of zirconium germanates leads to the formation of gaseous GeO{sub 2} and solid sintered ZrO{sub 2}. ?The temperature of decomposition is strongly depended on the total gas pressure.

  10. Hickey, TT136, casts 96-97 Hickey, TT136, casts 96-97, page 1

    E-print Network

    Hickey, Barbara

    Hickey, TT136, casts 96-97 Hickey, TT136, casts 96-97, page 1 CTD096 #12;Hickey, TT136, casts 96-97 Hickey, TT136, casts 96-97, page 2 CTD096 #12;Hickey, TT136, casts 96-97 Hickey, TT136, casts 96-97, page 3 CTD096 #12;Hickey, TT136, casts 96-97 Hickey, TT136, casts 96-97, page 4 CTD096 #12;Hickey, TT136

  11. Properties of polymeric zirconium phosphates as Friedel-Crafts catalysts

    Microsoft Academic Search

    M. Conceição Cruz Costa; Robert A. W. Johnstone; David Whittaker

    1995-01-01

    The activities of some amorphous and crystalline polymeric zirconium phosphates as Friedel-Crafts catalysts have been investigated. Catalytic behaviour was studied in the alkylation of anisole with alcohols in both liquid and gas phases and compared with the activity of alumina and acid activated clay. Under comparable experimental conditions, the catalytic activity of amorphous zirconium phosphate compares favourably with that shown

  12. Zirconium metal matrix-silicon carbide composite nuclear reactor components

    Microsoft Academic Search

    1987-01-01

    In a nuclear reactor having metallic components, the improvement is described wherein at least one metallic component is a composite metallic component. The composite metallic component comprises a member formed from 90-60 volume percent of a metal matrix of a metal selected from the group consisting essentially of zirconium and a zirconium alloy containing less than about 5 percent by

  13. Mechanism for zirconium oxide atomic layer deposition using bis,,methylcyclopentadienyl...methoxymethyl zirconium

    E-print Network

    Zirconium oxide ZrO2 is a promising high-dielectric constant replacement for SiO2 in future microelectronic for preparing ZrO2 thin films because it affords precise thick- ness control and superb conformality.5, ab initio calculations are performed to predict the order in which the ligands are lost during ZrO2

  14. Zirconium fluoride glass - Surface crystals formed by reaction with water

    NASA Technical Reports Server (NTRS)

    Doremus, R. H.; Bansal, N. P.; Bradner, T.; Murphy, D.

    1984-01-01

    The hydrated surfaces of a zirconium barium fluoride glass, which has potential for application in optical fibers and other optical elements, were observed by scanning electron microscopy. Crystalline zirconium fluoride was identified by analysis of X-ray diffraction patterns of the surface crystals and found to be the main constituent of the surface material. It was also found that hydrated zirconium fluorides form only in highly acidic fluoride solutions. It is possible that the zirconium fluoride crystals form directly on the glass surface as a result of its depletion of other ions. The solubility of zirconium fluoride is suggested to be probably much lower than that of barium fluoride (0.16 g/100 cu cm at 18 C). Dissolution was determined to be the predominant process in the initial stages of the reaction of the glass with water. Penetration of water into the glass has little effect.

  15. Irradiation growth in zirconium and its alloys

    NASA Astrophysics Data System (ADS)

    Rogerson, A.

    1988-10-01

    The UKAEA Northern Research Laboratories (Risley) have recently completed an underlying research study on irradiation growth in zirconium and its alloys. During this study, irradiation growth measurements have been made on a range of well-characterized single-crystal and polycrystalline iodide zirconium, commercial alloys Zircaloy-2 and Zr-2.5 wt% Nb, and high-purity zirconium-tin alloys in different metallurgical conditions following irradiation in the DIDO reactor at AERE Harwell. Irradiations were performed in three rigs operating at irradiation temperatures between 353 and 673 K. An important feature of the experimental programme was the capability to perform repeat length measurements on individual growth specimens at intervals during their irradiation programme. This facility has allowed accurate monitoring of the growth phenomenon and changes in growth behaviour induced by the combined effects of irradiation temperature and accumulated fast neutron dose over large dose ranges. This paper reviews the main experimental results from this programme and discusses them in terms of current understanding of the growth process. Thus, it has been observed that, in annealed Zircaloy-2 at temperatures between 553 and 673 K, a transition from saturating growth to accelerating growth rates occurs with increasing dose. The dose above which this "growth breakaway" takes place is seen to be inversely dependent on irradiation temperature in mis temperature range. The well-documented difference in growth behaviour between annealed and cold-worked Zircaloy-2 observed at relatively low irradiation temperatures, in which cold-worked material grows at a high linear rate over large dose ranges, is not observed at 673 K. Comparison is made with reported results on similar material irradiated in other irradiation facilities. The growth data are interpreted in terms of recent theories regarding the development during fast neutron irradiation of a cold-worked microstructure consisting of < a>- and < c>-type dislocations. Irradiation growth behaviour of annealed polycrystalline iodide zirconium between 353 and 673 K contrasts strongly with that in annealed Zircaloy-2 with low irradiation growth rates being observed over a large dose and temperature range. The influence of key irradiation parameters on the growth process have been examined in a series of studies initiated as part of a collaborative programme with AECL Chalk River Nuclear Labs. Final results from the studies on annealed and deformed single-crystal zirconium are reported here. They show that growth saturates rapidly at low dose in annealed single-crystal material irradiated at 353 and 553 K but that a gradual increase in growth strain is observed on irradiation to high dose at 553 K. Single-crystal specimens heavily swaged prior to irradiation at 353 K and given different pre-irradiation heat-treatments exhibit high near-linear or accelerating growth rates. These growth data are interpreted in terms of the importance of grain boundaries and twin boundaries as sinks for point defects which allow point defect separation and hence growth to continue to high dose. Finally, the results of growth experiments performed on Zr-0.1% Sn and Zr-1.5% Sn alloys at 353 and 553 K are reviewed. These experiments confirm the important role played by alloying additions and impurities on the growth process in zirconium and Zircaloy-2.

  16. Short-time oxidation of zirconium.

    NASA Technical Reports Server (NTRS)

    Srivastava, L. P.; Archbold, T. F.

    1972-01-01

    Study of zirconium oxidation kinetics for maximum exposure times of 3 min and in the temperature range 440 to 850 C. 'Discontinuous' oxidation runs were employed whereby a specimen was inserted into the gas stream for a predetermined time, removed and weighed, and reinserted into the oxidation atmosphere. It is considered that the increase in the observed activation energy for the early stage parabolic oxidation is a manifestation of a change from an n-type oxide to a predominantly p-type oxide, in agreement with the authors' earlier conclusion (1971) based on pressure effects.

  17. Cherenkov and Scintillation Properties of Cubic Zirconium

    NASA Technical Reports Server (NTRS)

    Christl, M.J.; Adams, J.H.; Parnell, T.A.; Kuznetsov, E.N.

    2008-01-01

    Cubic zirconium (CZ) is a high index of refraction (n =2.17) material that we have investigated for Cherenkov counter applications. Laboratory and proton accelerator tests of an 18cc sample of CZ show that the expected fast Cherenkov response is accompanied by a longer scintillation component that can be separated by pulse shaping. This presents the possibility of novel particle spectrometers which exploits both properties of CZ. Other high index materials being examined for Cherenkov applications will be discussed. Results from laboratory tests and an accelerator exposure will be presented and a potential application in solar energetic particle instruments will be discussed

  18. Creep Behavior of Hydrogenated Zirconium Alloys

    NASA Astrophysics Data System (ADS)

    Sarkar, A.; Boopathy, K.; Eapen, J.; Murty, K. L.

    2014-10-01

    Zirconium (Zr) alloys are the primary structural materials of most water reactors. Creep is considered to be one of the important degradation mechanisms of Zr alloys during reactor operating and repository conditions. Zr alloys pick up hydrogen (H2) during their service from the coolant water. Hydrogen can be present in solid solution or precipitated hydride form in Zr alloys depending upon the temperature and concentration. This study reviews the effect of hydrogen on creep behavior of Zr alloys used in the water reactors.

  19. Ballistic effectiveness of superdense solid composite propellants with zirconium or zirconium hydride

    NASA Astrophysics Data System (ADS)

    Lempert, D.; Manelis, G.; Nechiporenko, G.

    2011-10-01

    The ballistic effectiveness of propellants depends not only on the value of specific impulse but also on many other performances, primarily on the density. Despite the density itself does not enter the expression of the rocket velocity (W = Isp ln(Mlaunch/Mfinish) where Mlaunch and Mfinish are the rocket launch mass and its mass after the propellant is burnt, respectively), it in§uences the value Mlaunch/Mfinish of the specific rocket. If one charges the construction of fixed volume with a more dense propellant, the ratio Mlaunch/Mfinish increases and, consequently, W increases as well. In this paper, the possibility of creating solid composite propellants (SCP) with zirconium (density 6.49 g/cm3) and zirconium hydride (density 5.61 g/cm3 ) as energetic compounds instead of aluminum is considered. It was found for what kinds of engines these propellants have to be more effective than propellants based on aluminum.

  20. 9 CFR 201.97 - Annual reports.

    Code of Federal Regulations, 2010 CFR

    2010-01-01

    ...97 Animals and Animal Products GRAIN INSPECTION, PACKERS AND STOCKYARDS ADMINISTRATION (PACKERS AND STOCKYARDS PROGRAMS), DEPARTMENT OF AGRICULTURE REGULATIONS UNDER THE PACKERS AND STOCKYARDS ACT General § 201.97 Annual...

  1. Nucleation Pathways For Freezing Of Two Grades Of Zirconium

    NASA Technical Reports Server (NTRS)

    Rhim, Won-Kyu; Rulison, Aaron; Bayuzick, Robert; Hofmeister, William; Morton, Craig

    1996-01-01

    Report discusses classical nucleation theory of freezing and describes experimental study of nucleation mechanisms that predominate during freezing of spherical specimens of initially molten zirconium levitated electrostatically in vacuum.

  2. First principles modeling of zirconium solution in bulk UO2

    NASA Astrophysics Data System (ADS)

    Lan, Jian-Hui; Wang, Lin; Li, Shuo; Yuan, Li-Yong; Feng, Yi-Xiao; Sun, Wei; Zhao, Yu-Liang; Chai, Zhi-Fang; Shi, Wei-Qun

    2013-05-01

    We modeled the solution behavior of zirconium in uranium dioxide (UO2) by using density functional theory. The Coulomb repulsion of uranium 5f elections was characterized by a spherically averaged Hubbard parameter. Our results indicate that zirconium prefers to locate at U vacancies in UO2 and presents a slight tendency to accumulate in thermodynamics. The solution energies for hcp Zr metal and monoclinic ZrO2 indicates that these two precipitates are insoluble in UO2. In perfect UO2, the band-gap opening is governed by U 5f peaks around the Fermi energy, whereas the solution of zirconium further leads to the band gap splitting owing to the introduction of zirconium 4d peaks especially at high defect concentrations.

  3. Investigation of Electrochemical Recovery of Zirconium from Spent Nuclear Fuels

    SciTech Connect

    Michael Simpson; II-Soon Hwang

    2014-06-01

    This project uses both modeling and experimental studies to design optimal electrochemical technology methods for recovery of zirconium from used nuclear fuel rods for more effective waste management. The objectives are to provide a means of efficiently separating zirconium into metallic high-level waste forms and to support development of a process for decontamination of zircaloy hulls to enable their disposal as low- and intermediate-level waste. Modeling work includes extension of a 3D model previously developed by Seoul National University for uranium electrorefining by adding the ability to predict zirconium behavior. Experimental validation activities include tests for recovery of zirconium from molten salt solutions and aqueous tests using surrogate materials. *This is a summary of the FY 2013 progress for I-NERI project # 2010-001-K provided to the I-NERI office.

  4. Electrochemical study of corrosion phenomena in zirconium alloys

    E-print Network

    Treeman, Nicole M

    2005-01-01

    Shadow corrosion of zirconium alloy fuel cladding in BWR environments, the phenomenon in which accelerated corrosion is experienced when the cladding surface is in close proximity to other metals, has become a potentially ...

  5. Fatigue behavior of alpha-zirconium phosphate/epoxy nanocomposites

    E-print Network

    Varadharajan, Balaji R.

    2006-04-12

    Fatigue crack growth in ±-Zirconium phosphate/epoxy nanocomposites was investigated. A new fatigue testing technique was implemented for miniature samples. Two different methods ?strength of materials and Rayleigh-Ritz - were used in determining...

  6. 40 CFR 721.10152 - Oxirane, substituted silylmethyl-, hydrolysis products with alkanol zirconium(4+) salt and silica...

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ...silylmethyl-, hydrolysis products with alkanol zirconium(4+) salt and silica, acetates...silylmethyl-, hydrolysis products with alkanol zirconium(4+) salt and silica, acetates...hydrolysis products with alkanol zirconium(4+) salt and silica,...

  7. 40 CFR 721.10152 - Oxirane, substituted silylmethyl-, hydrolysis products with alkanol zirconium(4+) salt and silica...

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ...products with alkanol zirconium(4+) salt and silica, acetates (generic). 721...products with alkanol zirconium(4+) salt and silica, acetates (generic). ...products with alkanol zirconium(4+) salt and silica, acetates (PMN...

  8. 40 CFR 721.10152 - Oxirane, substituted silylmethyl-, hydrolysis products with alkanol zirconium(4+) salt and silica...

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ...products with alkanol zirconium(4+) salt and silica, acetates (generic). 721...products with alkanol zirconium(4+) salt and silica, acetates (generic). ...products with alkanol zirconium(4+) salt and silica, acetates (PMN...

  9. Zirconium Hydride Space Power Reactor design.

    NASA Technical Reports Server (NTRS)

    Asquith, J. G.; Mason, D. G.; Stamp, S.

    1972-01-01

    The Zirconium Hydride Space Power Reactor being designed and fabricated at Atomics International is intended for a wide range of potential applications. Throughout the program a series of reactor designs have been evaluated to establish the unique requirements imposed by coupling with various power conversion systems and for specific applications. Current design and development emphasis is upon a 100 kilowatt thermal reactor for application in a 5 kwe thermoelectric space power generating system, which is scheduled to be fabricated and ground tested in the mid 70s. The reactor design considerations reviewed in this paper will be discussed in the context of this 100 kwt reactor and a 300 kwt reactor previously designed for larger power demand applications.

  10. Plastic deformation of polycrystalline zirconium carbide

    NASA Technical Reports Server (NTRS)

    Darolia, R.; Archbold, T. F.

    1976-01-01

    The compressive yield strength of arc-melted polycrystalline zirconium carbide has been found to vary from 77 kg per sq mm at 1200 C to 19 kg per sq mm at 1800 C. Yield drops were observed with plastic strain-rates greater than 0.003/sec but not with slower strain rates. Strain-rate change experiments yielded values for the strain-rate sensitivity parameter m which range from 6.5 at 1500 C to 3.8 at 1800 C, and the product dislocation velocity stress exponent times T was found to decrease linearly with increasing temperature. The deformation rate results are consistent with the Kelly-Rowcliffe model in which the diffusion of carbon assists the motion of dislocations.

  11. Temperature dependence of damage accumulation in ?-zirconium

    NASA Astrophysics Data System (ADS)

    Arévalo, C.; Caturla, M. J.; Perlado, J. M.

    2007-08-01

    Using the input data obtained from molecular dynamics (MD) simulations on defect energetics and cascade damage, we present results obtained on irradiation of hexagonal-close-packed (hcp) ?-zirconium under different conditions with a kinetic Monte Carlo (kMC) model. We used three 25 keV cascade databases at temperatures of 100 K, 300 K and 600 K respectively. The evolution of the microstructure during irradiation for a dose rate of 10 -6 dpa/s, at temperatures of 100 K, 300 K and 600 K until a final dose of 0.1 dpa has been studied. We have considered isotropic motion for vacancies and one dimensional movement for interstitials and we have studied how the accumulation of damage is affected considering different temperatures. We present preliminary comparisons with experimental data.

  12. Critical role of nitrogen during high temperature scaling of zirconium

    NASA Technical Reports Server (NTRS)

    Evans, E. B.; Tsangarakis, N.; Probst, H. B.; Garibotti, N. J.

    1973-01-01

    The mechanisms of scale cracking, scale color changes, and scale growth, and their interrelations, were studied in zirconium specimens at elevated temperatures in air, oxygen and nitrogen. Nitrogen was found to be responsible for monoclinic-to-cubic ZrO2 conversion, for scale cracking and breakaway on zirconium nitride, and for the formation of ZrN on the metal interface underneath an outer oxide layer.

  13. ZIRCONIUM AND HAFNIUM (Data in metric tons unless otherwise noted)

    E-print Network

    were produced by the metal producer in Oregon and by at least 11 other companies. Zirconia (ZrO2, zircon (ZrO2 content) W W W W W Imports: Zirconium, ores and concentrates (ZrO2 content) 22,900 24,800 23 4 4 4 4 10 Exports: Zirconium ores and concentrates (ZrO2 content) 44,700 65,600 49,600 43,000 34

  14. ZIRCONIUM AND HAFNIUM (Data in metric tons, unless otherwise noted)

    E-print Network

    produced by 10 other companies. Zirconia (ZrO2) was produced from zircon sand at plants in Alabama, New (ZrO2 content)1 100,000 100,000 100,000 100,000 100,000 Imports: Zirconium, ores and concentrates (ZrO2 content) 60,100 40,600 58,200 37,500 42,600 Zirconium, alloys, waste and scrap (ZrO2 content) 836

  15. ZIRCONIUM AND HAFNIUM (Data in metric tons, unless otherwise noted)

    E-print Network

    chemicals were produced by 10 other companies. Zirconia (ZrO2) was produced from zircon sand at plants 2002e Production, zircon (ZrO2 content)1 100,000 100,000 100,000 100,000 100,000 Imports: Zirconium, ores and concentrates (ZrO2 content) 58,200 37,500 42,400 39,400 20,900 Zirconium, alloys, waste

  16. ZIRCONIUM AND HAFNIUM (Data in metric tons unless otherwise noted)

    E-print Network

    other companies. Zirconia (ZrO2) was produced from zircon sand at plants in Alabama, New Hampshire, New (ZrO2 content) W W W W W Imports: Zirconium, ores and concentrates (ZrO2 content) 42,400 39,400 22,900 24,300 20,300 Zirconium, alloys, waste and scrap, and powder (ZrO2 content) 1,400 850 750 308 278

  17. ZIRCONIUM AND HAFNIUM (Data in metric tons unless otherwise noted)

    E-print Network

    were produced by the metal producer in Oregon and by at least 11 other companies. Zirconia (ZrO2, zircon (ZrO2 content) W W W W W Imports: Zirconium, ores and concentrates (ZrO2 content) 24,300 22,900 24 5 4 4 4 4 Exports: Zirconium ores and concentrates (ZrO2 content) 45,900 44,700 65,600 49,600 48

  18. ZIRCONIUM AND HAFNIUM (Data in metric tons unless otherwise noted)

    E-print Network

    were produced by the metal producer in Oregon and by at least 10 other companies. Zirconia (ZrO2, zircon (ZrO2 content) W W W W W Imports: Zirconium, ores and concentrates (ZrO2 content) 24,800 23,500 13 and scrap 4 4 4 12 5 Exports: Zirconium ores and concentrates (ZrO2 content) 65,600 49,600 43,000 27,400 22

  19. ZIRCONIUM AND HAFNIUM (Data in metric tons, unless otherwise noted)

    E-print Network

    other companies. Zirconia (ZrO2) was produced from zircon sand at plants in Alabama, New Hampshire, New (ZrO2 content)1 100,000 100,000 100,000 100,000 100,000 Imports: Zirconium, ores and concentrates (ZrO2 content) 40,600 58,200 37,500 42,400 40,000 Zirconium, alloys, waste and scrap (ZrO2 content) 929

  20. Graded selective coatings based on zirconium and titanium oxynitride

    Microsoft Academic Search

    A. Rizzo; M. A. Signore; L. Tapfer; E. Piscopiello; A. Cappello; E. Bemporad; M. Sebastiani

    2009-01-01

    The aim of this study was the development and characterization of transition metal oxynitride multilayers for optical applications. The reactive RF magnetron sputtering technique in rotation mode was used for stacking of zirconium oxynitride (ZrNO) and titanium oxynitride (TiNO) nanolayers. The depositions were carried out in a reactive Ar+N2+O2 atmosphere by sputtering titanium and zirconium targets. By means of different

  1. 27 CFR 21.97 - Benzene.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ...2010-04-01 2010-04-01 false Benzene. 21.97 Section 21.97 Alcohol...Specifications for Denaturants § 21.97 Benzene. (a) Distillation range. ...see § 21.6(b).) When 100 ml of benzene are distilled by this method, not...

  2. 27 CFR 21.97 - Benzene.

    Code of Federal Regulations, 2011 CFR

    2011-04-01

    ...2011-04-01 2011-04-01 false Benzene. 21.97 Section 21.97 Alcohol...Specifications for Denaturants § 21.97 Benzene. (a) Distillation range. ...see § 21.6(b).) When 100 ml of benzene are distilled by this method, not...

  3. 27 CFR 21.97 - Benzene.

    Code of Federal Regulations, 2013 CFR

    2013-04-01

    ...2013-04-01 2013-04-01 false Benzene. 21.97 Section 21.97 Alcohol...Specifications for Denaturants § 21.97 Benzene. (a) Distillation range. ...see § 21.6(b).) When 100 ml of benzene are distilled by this method, not...

  4. 27 CFR 21.97 - Benzene.

    Code of Federal Regulations, 2014 CFR

    2014-04-01

    ...2014-04-01 2014-04-01 false Benzene. 21.97 Section 21.97 Alcohol...Specifications for Denaturants § 21.97 Benzene. (a) Distillation range. ...see § 21.6(b).) When 100 ml of benzene are distilled by this method, not...

  5. 27 CFR 21.97 - Benzene.

    Code of Federal Regulations, 2012 CFR

    2012-04-01

    ...2012-04-01 2012-04-01 false Benzene. 21.97 Section 21.97 Alcohol...Specifications for Denaturants § 21.97 Benzene. (a) Distillation range. ...see § 21.6(b).) When 100 ml of benzene are distilled by this method, not...

  6. 46 CFR 97.15-10 - Sanitation.

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ... Shipping 4 2010-10-01 2010-10-01 false Sanitation. 97.15-10 Section 97.15-10 Shipping COAST...OPERATIONS Tests, Drills, and Inspections § 97.15-10 Sanitation. (a) It shall be the duty of the master and chief...

  7. 27 CFR 6.97 - [Reserved

    Code of Federal Regulations, 2013 CFR

    2013-04-01

    27 ? Alcohol, Tobacco Products and Firearms ? 1 ? 2013-04-01 ? 2013-04-01 ? false ? [Reserved] ? 6.97 ? Section 6.97 ? Alcohol, Tobacco Products and Firearms ? ALCOHOL AND TOBACCO TAX AND TRADE BUREAU, DEPARTMENT OF THE TREASURY ? ALCOHOL ? âTIED-HOUSEâ ? Exceptions ? § 6.97 ?...

  8. 27 CFR 6.97 - [Reserved

    Code of Federal Regulations, 2014 CFR

    2014-04-01

    27 ? Alcohol, Tobacco Products and Firearms ? 1 ? 2014-04-01 ? 2014-04-01 ? false ? [Reserved] ? 6.97 ? Section 6.97 ? Alcohol, Tobacco Products and Firearms ? ALCOHOL AND TOBACCO TAX AND TRADE BUREAU, DEPARTMENT OF THE TREASURY ? ALCOHOL ? âTIED-HOUSEâ ? Exceptions ? § 6.97 ?...

  9. 47 CFR 97.503 - Element standards.

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ...2010-10-01 2010-10-01 false Element standards. 97.503 Section 97...Qualifying Examination Systems § 97.503 Element standards. A written examination...of a question set as follows: (a) Element 2: 35 questions concerning the...

  10. 47 CFR 97.503 - Element standards.

    Code of Federal Regulations, 2011 CFR

    2011-10-01

    ...2011-10-01 2011-10-01 false Element standards. 97.503 Section 97...Qualifying Examination Systems § 97.503 Element standards. A written examination...of a question set as follows: (a) Element 2: 35 questions concerning the...

  11. 47 CFR 97.505 - Element credit.

    Code of Federal Regulations, 2011 CFR

    2011-10-01

    ...2011-10-01 2011-10-01 false Element credit. 97.505 Section 97.505...Qualifying Examination Systems § 97.505 Element credit. (a) The administering...Advanced Class operator license grant: Elements 2 and 3. (2) An unexpired...

  12. 47 CFR 97.503 - Element standards.

    Code of Federal Regulations, 2013 CFR

    2013-10-01

    ...2013-10-01 2013-10-01 false Element standards. 97.503 Section 97...Qualifying Examination Systems § 97.503 Element standards. A written examination...of a question set as follows: (a) Element 2: 35 questions concerning the...

  13. 47 CFR 97.505 - Element credit.

    Code of Federal Regulations, 2012 CFR

    2012-10-01

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  14. 47 CFR 97.505 - Element credit.

    Code of Federal Regulations, 2013 CFR

    2013-10-01

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  15. 47 CFR 97.503 - Element standards.

    Code of Federal Regulations, 2012 CFR

    2012-10-01

    ...2012-10-01 2012-10-01 false Element standards. 97.503 Section 97...Qualifying Examination Systems § 97.503 Element standards. A written examination...of a question set as follows: (a) Element 2: 35 questions concerning the...

  16. 47 CFR 97.505 - Element credit.

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ...2010-10-01 2010-10-01 false Element credit. 97.505 Section 97.505...Qualifying Examination Systems § 97.505 Element credit. (a) The administering...Advanced Class operator license grant: Elements 2 and 3. (2) An unexpired...

  17. 28 CFR 97.12 - Employee training.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ...2010-07-01 2010-07-01 false Employee training. 97.12 Section 97.12...DETAINEE SERVICES § 97.12 Employee training. Private prisoner transport...of a minimum of 100 hours of employee training before an employee may...

  18. 28 CFR 97.12 - Employee training.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

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  19. 28 CFR 97.12 - Employee training.

    Code of Federal Regulations, 2014 CFR

    2014-07-01

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  20. 28 CFR 97.12 - Employee training.

    Code of Federal Regulations, 2012 CFR

    2012-07-01

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  1. 28 CFR 97.12 - Employee training.

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ...2013-07-01 2013-07-01 false Employee training. 97.12 Section 97.12...DETAINEE SERVICES § 97.12 Employee training. Private prisoner transport...of a minimum of 100 hours of employee training before an employee may...

  2. 47 CFR 97.503 - Element standards.

    Code of Federal Regulations, 2014 CFR

    2014-10-01

    ...2014-10-01 2014-10-01 false Element standards. 97.503 Section 97...Qualifying Examination Systems § 97.503 Element standards. A written examination...of a question set as follows: (a) Element 2: 35 questions concerning the...

  3. 7 CFR 97.14 - Joint applicants.

    Code of Federal Regulations, 2011 CFR

    2011-01-01

    ...Agriculture 3 2011-01-01 2011-01-01 false Joint applicants. 97.14 Section 97.14 Agriculture...VARIETY AND PROTECTION The Application § 97.14 Joint applicants. (a) Joint owners shall file a joint application by...

  4. Quercetin as colorimetric reagent for determination of zirconium

    USGS Publications Warehouse

    Grimaldi, F.S.; White, C.E.

    1953-01-01

    Methods described in the literature for the determination of zirconium are generally designed for relatively large amounts of this element. A good procedure using colorimetric reagent for the determination of trace amounts is desirable. Quercetin has been found to yield a sensitive color reaction with zirconium suitable for the determination of from 0.1 to 50?? of zirconium dioxide. The procedure developed involves the separation of zirconium from interfering elements by precipitation with p-dimethylaminoazophenylarsonic acid prior to its estimation with quercetin. The quercetin reaction is carried out in 0.5N hydrochloric acid solution. Under the operating conditions it is indicated that quercetin forms a 2 to 1 complex with zirconium; however, a 2 to 1 and a 1 to 1 complex can coexist under special conditions. Approximate values for the equilibrium constants of the complexes are K1 = 0.33 ?? 10-5 and K2 = 1.3 ?? 10-9. Seven Bureau of Standards samples of glass sands and refractories were analyzed with excellent results. The method described should find considerable application in the analysis of minerals and other materials for macro as well as micro amounts of zirconium.

  5. Zirconium alkoxide interfaces for adhesion enhancement and electrocatalysis

    NASA Astrophysics Data System (ADS)

    Vanderkam, Susan Killian

    Tetra(tert-butoxy)zirconium was chemisorbed onto the native oxide layers of aluminum, iron, copper, and porous silicon, forming surface bound di- or tri-alkoxy zirconium species. Poly(ethylene- co-acrylic acid) was subsequently reacted with the surface forming chemically bound copolymer through carboxyzirconium linkages. Copolymer bound through the zirconium complex adhered to the metal oxide surfaces better than without the zirconium alkoxide intermediate, as determined by FTIR spectroscopy. Copper substrates were subjected to a variety of stability tests, including exposure to ambient conditions, base washing, and chronocoulometry. The copper-zirconium-copolymer ensemble was shown to be very stable in all of these tests. Indium tin oxide (ITO) powder was titrated to determine surface hydroxyl content per unit area. ITO-coated glass slides were reacted with tetra( tert-butoxy)zirconium, and subsequently with both carboxylic acid and phenol derivatives. Ferrocene-carboxyzirconium-coated ITO was characterized electrochemically, and the surface loading of ferrocene was found to be approximately one monolayer. Phenoxyzirconium-coated ITO was also characterized electrochemically and tested for electrocatalytic properties for the oxidation of several compounds in solution. Phenoxyzirconium-coated ITO was found to improve the oxidation kinetics for ferrocene and tetramethylphenylenediamine in acetonitrile.

  6. Understanding the Irradiation Behavior of Zirconium Carbide

    SciTech Connect

    Motta, Arthur; Sridharan, Kumar; Morgan, Dane; Szlufarska, Izabela

    2013-10-11

    Zirconium carbide (ZrC) is being considered for utilization in high-temperature gas-cooled reactor fuels in deep-burn TRISO fuel. Zirconium carbide possesses a cubic B1-type crystal structure with a high melting point, exceptional hardness, and good thermal and electrical conductivities. The use of ZrC as part of the TRISO fuel requires a thorough understanding of its irradiation response. However, the radiation effects on ZrC are still poorly understood. The majority of the existing research is focused on the radiation damage phenomena at higher temperatures (>450{degree}C) where many fundamental aspects of defect production and kinetics cannot be easily distinguished. Little is known about basic defect formation, clustering, and evolution of ZrC under irradiation, although some atomistic simulation and phenomenological studies have been performed. Such detailed information is needed to construct a model describing the microstructural evolution in fast-neutron irradiated materials that will be of great technological importance for the development of ZrC- based fuel. The goal of the proposed project is to gain fundamental understanding of the radiation-induced defect formation in zirconium carbide and irradiation response (ZrC) by using a combination of state-of-the-art experimental methods and atomistic modeling. This project will combine (1) in situ ion irradiation at a specialized facility at a national laboratory, (2) controlled temperature proton irradiation on bulk samples, and (3) atomistic modeling to gain a fundamental understanding of defect formation in ZrC. The proposed project will cover the irradiation temperatures from cryogenic temperature to as high as 800{degree}C, and dose ranges from 0.1 to 100 dpa. The examination of this wide range of temperatures and doses allows us to obtain an experimental data set that can be effectively used to exercise and benchmark the computer calculations of defect properties. Combining the examination of radiation-induced microstructures mapped spatially and temporally, microstructural evolution during post-irradiation annealing, and atomistic modeling of defect formation and transport energetics will provide new, critical understanding about property changes in ZrC. The behavior of materials under irradiation is determined by the balance between damage production, defect clustering, and lattice response. In order to predict those effects at high temperatures so targeted testing can be expanded and extrapolated beyond the known database, it is necessary to determine the defect energetics and mobilities as these control damage accumulation and annealing. In particular, low-temperature irradiations are invaluable for determining the regions of defect mobility. Computer simulation techniques are particularly useful for identifying basic defect properties, especially if closely coupled with a well-constructed and complete experimental database. The close coupling of calculation and experiment in this project will provide mutual benchmarking and allow us to glean a deeper understanding of the irradiation response of ZrC, which can then be applied to the prediction of its behavior in reactor conditions.

  7. Evaluating zirconium-zirconium hydride interfacial strains by nano-beam electron diffraction

    NASA Astrophysics Data System (ADS)

    Barrow, A. T. W.; Korinek, A.; Daymond, M. R.

    2013-01-01

    Nano-beam electron diffraction has been used to quantify the elastic strain field associated with ?-hydride needles embedded in an ?-Zr matrix. It has been found that the volume misfit associated with precipitation results in elastic strains that are ˜4× greater in the matrix than the hydride. Electron energy loss spectroscopy was used to detect hydrogen enrichment at the matrix-hydride interface by a shift in the zirconium plasmon peak. This work highlights that ?-hydride is metastable and acts as a precursor to equilibrium ?-hydride and that compositional variations within the hydride can be detected using electron energy loss spectroscopy.

  8. 21 CFR 700.16 - Use of aerosol cosmetic products containing zirconium.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ...2010-04-01 2010-04-01 false Use of aerosol cosmetic products containing zirconium...Cosmetic Products § 700.16 Use of aerosol cosmetic products containing zirconium...that are also drugs, as, for example, aerosol antiperspirants. Evidence...

  9. Morphologies and growth mechanisms of zirconium carbide films by chemical vapor deposition

    Microsoft Academic Search

    Qiaomu Liu; Litong Zhang; Laifei Cheng; Yiguang Wang

    2009-01-01

    Zirconium carbide films were grown on graphite slices by chemical vapor deposition using methane, zirconium tetrachloride,\\u000a and hydrogen as precursors. The growth rate of zirconium carbide films as a function of temperature was investigated. The\\u000a morphologies of these films at different temperatures were also observed by scanning electron microscopy. The results indicated\\u000a that the deposition of zirconium carbide was dominated

  10. Elimination of phosphate and zirconium in the high-activity fraction resulting from TRUEX partitioning of ICPP zirconium calcines

    SciTech Connect

    Brewer, K.N.; Tillotson, R.D.; Tullock, P.A. [and others

    1997-07-01

    Laboratory testing was undertaken with the aim of developing a TRUEX flowsheet that would efficiently remove actinides from solutions of dissolved zirconium calcine and minimize the glass volume produced from the ensuing high-activity fraction. A TRUEX flowsheet is recommended for testing in the 2-cm centrifugal contactor pilot-plant based on the results from this testing. These laboratory tests show that zirconium recovery in the high activity fraction is minimized by scrubbing with an optimized NHF concentration of 0.2 M. This NH4F concentration in the scrub allowed the HEDPA strip concentration to be reduced from 0.04 M to 0.004 M because HEDPA is not consumed by zirconium. Complete TRU stripping was also achieved in these laboratory tests with 0.004 M HEDPA. Data from the small-scale laboratory batch contact tests were used in the Generic TRUEX Model (GTM) to evaluate the proposed flowsheet under counter-current conditions. GTM results indicate the raffinate will meet the Class A non-TRU limit of < 10 nCi/g in six extraction stages (O/A = 1), and quantitative actinide recovery will be achieved with the 0.004 M HEDPA in six strip stages (O/A = 1). Only 6.6 % of the initial zirconium concentration is anticipated to be recovered with the actinides, indicating the four scrub stages (O/A = 3) efficiently removes zirconium from the TRUEX solvent. In addition to recommending an improved TRUEX flowsheet for testing in the 2-cm centrifugal contactor pilot-plant, this work has shown that small reductions in zirconium extraction drastically improves flowsheet performance. These small changes in zirconium extraction can be accomplished by modifying the calcine dissolution parameters. Therefore, further calcine dissolution testing followed by TRUEX testing with the resulting feed solutions is also recommended.

  11. Chemical vapour deposition of zirconium carbide and silicon carbide hybrid whiskers

    Microsoft Academic Search

    Qiaomu Liu; Litong Zhang; Laifei Cheng; Yiguang Wang

    2010-01-01

    Zirconium carbide and silicon carbide hybrid whiskers were codeposited by chemical vapour deposition using methyl trichlorosilane, zirconium chloride, methane and hydrogen as the precursors. The zirconium carbide and silicon carbide whiskers were characterized by scanning electron microscopy, energy dispersive X-ray spectroscopy and X-ray diffraction. The results indicate that the codeposition process is more effective in the presence of methane than

  12. Atomic layer deposition of zirconium silicate films using zirconium tetrachloride and tetra-n-butyl orthosilicate

    NASA Astrophysics Data System (ADS)

    Kim, Won-Kyu; Kang, Sang-Woo; Rhee, Shi-Woo; Lee, Nae-In; Lee, Jong-Ho; Kang, Ho-Kyu

    2002-11-01

    Atomic layer chemical vapor deposition of zirconium silicate films with a precursor combination of ZrCl4 and tetra-n-butyl orthosilicate (TBOS) was studied for high dielectric gate insulators. The effect of deposition conditions, such as deposition temperature, pulse time for purge and precursor injection on the deposition rate per cycle, and composition of the film were studied. At 400 °C, the growth rate saturated to 1.35 Å/cycle above 500 sccm of the argon purge flow rate. The growth rate, composition ratio ((Zr/Zr+Si)), and impurity contents (carbon and chlorine) saturated with the increase of the injection time of ZrCl4 and TBOS and decreased with the increased deposition temperature from 300 to 500 °C. The growth rate, composition ratio, carbon, and chlorine contents of the Zr silicate thin films deposited at 500 °C were 1.05 Å/cycle, 0.23, 1.1 at. %, and 2.1 at. %, respectively. It appeared that by using only zirconium chloride and silicon alkoxide sources, the content of carbon and chlorine impurities could not be lowered below 1%. It was also found that the incorporation rate of metal from halide source was lower than alkoxide source.

  13. Inhibition of Ice Growth and Recrystallization by Zirconium Acetate and Zirconium Acetate Hydroxide

    PubMed Central

    Mizrahy, Ortal; Bar-Dolev, Maya; Guy, Shlomit; Braslavsky, Ido

    2013-01-01

    The control over ice crystal growth, melting, and shaping is important in a variety of fields, including cell and food preservation and ice templating for the production of composite materials. Control over ice growth remains a challenge in industry, and the demand for new cryoprotectants is high. Naturally occurring cryoprotectants, such as antifreeze proteins (AFPs), present one solution for modulating ice crystal growth; however, the production of AFPs is expensive and inefficient. These obstacles can be overcome by identifying synthetic substitutes with similar AFP properties. Zirconium acetate (ZRA) was recently found to induce the formation of hexagonal cavities in materials prepared by ice templating. Here, we continue this line of study and examine the effects of ZRA and a related compound, zirconium acetate hydroxide (ZRAH), on ice growth, shaping, and recrystallization. We found that the growth rate of ice crystals was significantly reduced in the presence of ZRA and ZRAH, and that solutions containing these compounds display a small degree of thermal hysteresis, depending on the solution pH. The compounds were found to inhibit recrystallization in a manner similar to that observed in the presence of AFPs. The favorable properties of ZRA and ZRAH suggest tremendous potential utility in industrial applications. PMID:23555701

  14. Structure of the AAA ATPase p97

    Microsoft Academic Search

    Xiaodong Zhang; Anthony Shaw; Paul A. Bates; Richard H. Newman; Brent Gowen; Elena Orlova; Michael A. Gorman; Hisao Kondo; Pawel Dokurno; John Lally; Gordon Leonard; Hemmo Meyer; Marin van Heel; Paul S. Freemont

    2000-01-01

    p97, an abundant hexameric ATPase of the AAA family, is involved in homotypic membrane fusion. It is thought to disassemble SNARE complexes formed during the process of membrane fusion. Here, we report two structures: a crystal structure of the N-terminal and D1 ATPase domains of murine p97 at 2.9 Å resolution, and a cryoelectron microscopy structure of full-length rat p97

  15. Chemistry of zirconium related to the behavior of nuclear fuel cladding. Final report

    SciTech Connect

    Cubicciotti, D.

    1980-03-26

    Studies of the chemistry of the zirconium-iodine and zirconium-oxygen systems were undertaken to elucidate their thermodynamics and kinetics. It is anticipated that the results obtained will lead to an improved understanding of the chemical processes involved in chemically assisted fuel rod failures. This project not only has classified the thermodynamics of both the gas phase and the solids in the zirconium-iodine system, it has also provided valuable information on the chemisorption of iodine and of oxygen on zirconium surfaces at high temperatures. In addition, the kinetics of reactions on zirconium surfaces were studied. These results have already been helpful in understanding the stress corrosion cracking of Zircaloy.

  16. Zirconium determination by cooling curve analysis during the pyroprocessing of used nuclear fuel

    NASA Astrophysics Data System (ADS)

    Westphal, B. R.; Price, J. C.; Bateman, K. J.; Marsden, K. C.

    2015-02-01

    An alternative method to sampling and chemical analyses has been developed to monitor the concentration of zirconium in real-time during the casting of uranium products from the pyroprocessing of used nuclear fuel. The method utilizes the solidification characteristics of the uranium products to determine zirconium levels based on standard cooling curve analyses and established binary phase diagram data. Numerous uranium products have been analyzed for their zirconium content and compared against measured zirconium data. From this data, the following equation was derived for the zirconium content of uranium products:

  17. A simple way to prepare precursors for zirconium carbide

    Microsoft Academic Search

    Dan Zhao; Haifeng Hu; Changrui Zhang; Yudi Zhang; Jun Wang

    2010-01-01

    A precursor for zirconium carbide was obtained by just blending zirconium butoxide Zr(OC4H9)4 (ZTB) and divinylbenzene (DVB). This precursor satisfied the requirements for use in ceramic matrix composites fabrication\\u000a via precursor infiltration and pyrolysis (PIP) process, that is, it was a solution, cross-linked at 150 °C for 2 h, and transformed\\u000a to ZrC matrix upon heat treatment at 1,600 °C with a ceramic

  18. First Order Pyramidal Slip of Screw Dislocations in Zirconium

    NASA Astrophysics Data System (ADS)

    Chaari, Nermine; Clouet, Emmanuel; Rodney, David

    2014-12-01

    Atomistic simulations, based either on an empirical interatomic potential or on ab initio calculations, are used to study the pyramidal glide of a 1/3 <1-210> screw dislocation in hexagonal close-packed zirconium. Generalized stacking fault calculations reveal a metastable stacking fault in the first order pyramidal {10-11} plane, which corresponds to an elementary pyramidal twin. This fault is at the origin of a metastable configuration of the screw dislocation in zirconium, which spontaneously appears when the dislocation glides in the pyramidal plane.

  19. In-situ stabilization of radioactive zirconium swarf

    DOEpatents

    Hess, Clay C. (Idaho Falls, ID)

    1999-01-01

    The method for treating ignitable cutting swarf in accordance with the present invention involves collecting cutting swarf in a casting mold underwater and injecting a binder mixture comprising vinyl ester styrene into the vessel to fill void volume; and form a mixture comprising swarf and vinyl ester styrene; and curing the mixture. The method is especially useful for stabilizing the ignitable characteristics of radioactive zirconium cutting swarf, and can be used to solidify zirconium swarf, or other ignitable finely divided material, underwater. The process could also be performed out of water with other particulate wastes.

  20. In-situ stabilization of radioactive zirconium swarf

    DOEpatents

    Hess, C.C.

    1999-08-31

    The method for treating ignitable cutting swarf in accordance with the present invention involves collecting cutting swarf in a casting mold underwater and injecting a binder mixture comprising vinyl ester styrene into the vessel to fill void volume; and form a mixture comprising swarf and vinyl ester styrene; and curing the mixture. The method is especially useful for stabilizing the ignitable characteristics of radioactive zirconium cutting swarf, and can be used to solidify zirconium swarf, or other ignitable finely divided material, underwater. The process could also be performed out of water with other particulate wastes. 6 figs.

  1. Radiochemical separation of zirconium and hafnium from other radionuclides.

    PubMed

    Hahn, R B

    1972-11-01

    Radiozirconium and radiohafnium may be separated from all other radionuclides except scandium and protactinium by precipitation with mandelic acid from 5-10 M hydrochloric acid, using commercial zirconyl chloride as carrier. Scandium and protactinium are removed by dissolving the precipitate in sodium carbonate, then adding barium nitrate to precipitate barium carbonate which acts as a scavenger. Zirconium mandelate is finally reprecipitated and the sample weighed and counted in this form. The method was checked by analysing commercial zirconyl chloride and standard rock samples for zirconium and hafnium by neutron-activation analysis. PMID:18961201

  2. EXAFS Studies of Amorphous Nickel-Zirconium Alloys

    NASA Astrophysics Data System (ADS)

    Maeda, Hironobu; Fukunaga, Toshiharu; Suzuki, Kenji; Osamura, Kouzo; Hida, Moritaka; Terauchi, Hikaru; Kamijo, Nagao

    1988-06-01

    Extended X-ray absorption fine structure (EXAFS) measurements have been made on the zirconium K absorption edge in amorphous NixZr1-x alloys with x{=}0.33, 0.50 and 0.67. The aim of this study is to understand the local structure vs composition in this system. It has been revealed as follows: (a) the bond length are 2.57 Å for the Zr-Ni pair and remain constant over the whole concentration range; (b) the second peak of the radial structure function consists of two component atoms, zirconium atom and nickel atom.

  3. Hydrogen pickup mechanism of zirconium alloys

    NASA Astrophysics Data System (ADS)

    Couet, Adrien

    Although the optimization of zirconium based alloys has led to significant improvements in hydrogen pickup and corrosion resistance, the mechanisms by which such alloy improvements occur are still not well understood. In an effort to understand such mechanisms, a systematic study of the alloy effect on hydrogen pickup is conducted, using advanced characterization techniques to rationalize precise measurements of hydrogen pickup. The hydrogen pick-up fraction is accurately measured for a specially designed set of commercial and model alloys to investigate the effects of alloying elements, microstructure and corrosion kinetics on hydrogen uptake. Two different techniques to measure hydrogen concentrations were used: a destructive technique, Vacuum Hot Extraction, and a non-destructive one, Cold Neutron Prompt Gamma Activation Analysis. The results indicate that hydrogen pickup varies not only from alloy to alloy but also during the corrosion process for a given alloy. For instance Zircaloy type alloys show high hydrogen pickup fraction and sub-parabolic oxidation kinetics whereas ZrNb alloys show lower hydrogen pickup fraction and close to parabolic oxidation kinetics. Hypothesis is made that hydrogen pickup result from the need to balance charge during the corrosion reaction, such that the pickup of hydrogen is directly related to (and indivisible of) the corrosion mechanism and decreases when the rate of electron transport or oxide electronic conductivity sigmao xe through the protective oxide increases. According to this hypothesis, alloying elements (either in solid solution or in precipitates) embedded in the oxide as well as space charge variations in the oxide would impact the hydrogen pick-up fraction by modifying sigmaox e, which drives oxidation and hydriding kinetics. Dedicated experiments and modelling were performed to assess and validate these hypotheses. In-situ electrochemical impedance spectroscopy (EIS) experiments were performed on Zircaloy-4 tubes to directly measure the evolution of sigma oxe as function of exposure time. The results show that sigmao xe decreases as function of exposure time and that its variations are directly correlated to the instantaneous hydrogen pickup fraction variations. The electron transport through the oxide layer is thus altered as the oxide grows, reasons for which are yet to be exactly determined. Preliminary results also show that sigma oxe of ZrNb alloys would be much higher compared with Zircaloy-4. Thus, it is confirmed that sigmaox e is a key parameter in the hydrogen and oxidation mechanism. Because the mechanism whereby alloying elements are incorporated into the oxide layer is critical to changing sigmao xe, the evolution of the oxidation state of two common alloying elements, Fe and Nb, when incorporated into the growing oxide layers is investigated using X-Ray Absorption Near-Edge Spectroscopy (XANES) using micro-beam synchrotron radiation on cross sectional oxide samples. The results show that the oxidation of both Fe and Nb is delayed in the oxide layer compared to that of Zr, and that this oxidation delay is related to the variations of the instantaneous hydrogen pick-up fraction with exposure time. The evolution of Nb oxidation as function of oxide depth is also compatible with space charge compensation in the oxide and with an increase in sigmaox e of ZrNb alloys compared to Zircaloys. Finally, various successively complex models from the well-known Wagner oxidation theory to the more complex effect of space charge on oxidation kinetics have been developed. The general purpose of the modeling effort is to provide a rationale for the sub-parabolic oxidation kinetics and demonstrate the correlation with hydrogen pickup fraction. It is directly demonstrated that parabolic oxidation kinetics is associated with high sigmao xe and low space charges in the oxide whereas sub-parabolic oxidation kinetics is associated with lower sigmaox e and higher space charge in the oxide. All these observations helped us to propose a general corrosion mechanism of zirconium allo

  4. 40 CFR 97.362 - Notification.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ...SO2 TRADING PROGRAMS CAIR NOX Ozone Season Allowance Transfers § 97.362 Notification...days of recordation of a CAIR NOX Ozone Season allowance transfer under § 97.361...days of receipt of a CAIR NOX Ozone Season allowance transfer that fails to...

  5. 40 CFR 97.380 - Applicability.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ...Applicability. A CAIR NOX Ozone Season opt-in unit must...procedures concerning CAIR Ozone Season opt-in units; (b) Is not a CAIR NOX Ozone Season unit under § 97...under § 97.305 that is in effect; (c) Is not...

  6. Characterization of uranium and uranium-zirconium deposits produced in electrorefining of spent nuclear fuel

    SciTech Connect

    Totemeier, T.C.

    1997-09-01

    This paper describes the metallurgical characterization of deposits produced in molten salt electrorefining of uranium and uranium - 10.% zirconium alloy. The techniques of characterization are described with emphasis on considerations given to the radioactive and pyrophoric nature of the samples. The morphologies observed and their implications for deposit performance are also presented - samples from pure uranium deposits were comprised of chains of uranium crystals with a characteristic rhomboidal shape, while morphologies of samples from deposits containing zirconium showed more polycrystalline features. Zirconium was found to be present as a second, zirconium metal phase at or very near the uranium-zirconium dendrite surfaces. Higher collection efficiencies and total deposit weights were observed for the uranium-zirconium deposits; this performance increase is likely a result of better mechanical properties exhibited by the uranium-zirconium dendrite morphology. 18 refs., 10 figs., 1 tab.

  7. Zirconium nanoparticles prepared by the reduction of zirconium oxide using the RAPET method

    PubMed Central

    Eshed, Michal; Pol, Swati; Balasubramanian, Mahalingam

    2011-01-01

    Summary The aim of the current work is the synthesis and characterization of metallic Zr nanoparticles. The preparation is carried out by using the RAPET method (Reaction under Autogenic Pressure at Elevated Temperatures) developed in our lab. The RAPET reaction of commercial ZrO2 with Mg powder was carried out in a closed stainless steel cell, at 750 °C. On completion of the reaction, the additionally formed MgO is removed by treatment with acid. The characterization of the product was performed by XRD, X-ray absorption spectroscopy, SEM, TEM and elemental analysis. The XRD pattern reveals that the product is composed of pure metallic zirconium, without any traces of the MgO by-product. PMID:21977431

  8. Manufacturing process to reduce large grain growth in zirconium alloys

    DOEpatents

    Rosecrans, Peter M. (Niskayuna, NY)

    1987-01-01

    A method of treating cold-worked zirconium alloys to reduce large grain gth during thermal treatment at temperatures above the recrystallization temperature of the alloy comprising heating the cold-worked alloy between about 1300.degree.-1350.degree. F. for 1 to 3 hours prior to treatment above its recrystallization temperature.

  9. Synthesis and Liquid Crystal Phase Transitions of Zirconium Phosphate Disks

    E-print Network

    Shuai, Min

    2013-05-07

    -shaped nanoparticles, and use it for the study of self-assembly and discotic liquid crystal phase transitions of discotic particles. The work was introduced by the control over the size and polydispersity of zirconium phosphate (ZrP) disks through synthesis...

  10. Solid State Phase Transformations in Uranium-Zirconium Alloys

    E-print Network

    Irukuvarghula, Sandeep

    2013-08-06

    , a basic study on the U-Zr metallurgy was completed using EPMA, DSC, XRD, Optical microscopy, and TEM with a focus on solid state phase transformations in alloys containing 2, 5, 10, 20, 30, and 50wt% zirconium. Alloys were cast by crucible melting...

  11. Nanophase Nickel-Zirconium Alloys for Fuel Cells

    NASA Technical Reports Server (NTRS)

    Narayanan, Sekharipuram; Whitacre, jay; Valdez, Thomas

    2008-01-01

    Nanophase nickel-zirconium alloys have been investigated for use as electrically conductive coatings and catalyst supports in fuel cells. Heretofore, noble metals have been used because they resist corrosion in the harsh, acidic fuel cell interior environments. However, the high cost of noble metals has prompted a search for less-costly substitutes. Nickel-zirconium alloys belong to a class of base metal alloys formed from transition elements of widely different d-electron configurations. These alloys generally exhibit unique physical, chemical, and metallurgical properties that can include corrosion resistance. Inasmuch as corrosion is accelerated by free-energy differences between bulk material and grain boundaries, it was conjectured that amorphous (glassy) and nanophase forms of these alloys could offer the desired corrosion resistance. For experiments to test the conjecture, thin alloy films containing various proportions of nickel and zirconium were deposited by magnetron and radiofrequency co-sputtering of nickel and zirconium. The results of x-ray diffraction studies of the deposited films suggested that the films had a nanophase and nearly amorphous character.

  12. Method for calcining nuclear waste solutions containing zirconium and halides

    DOEpatents

    Newby, Billie J. (Idaho Falls, ID)

    1979-01-01

    A reduction in the quantity of gelatinous solids which are formed in aqueous zirconium-fluoride nuclear reprocessing waste solutions by calcium nitrate added to suppress halide volatility during calcination of the solution while further suppressing chloride volatility is achieved by increasing the aluminum to fluoride mole ratio in the waste solution prior to adding the calcium nitrate.

  13. Discovery of Yttrium, Zirconium, Niobium, Technetium, and Ruthenium Isotopes

    E-print Network

    Nystrom, A

    2011-01-01

    Currently, thirty-four yttrium, thirty-five zirconium, thirty-four niobium, thirty-five technetium, and thirty-eight ruthenium isotopes have been observed and the discovery of these isotopes is discussed here. For each isotope a brief synopsis of the first refereed publication, including the production and identification method, is presented.

  14. Discovery of Yttrium, Zirconium, Niobium, Technetium, and Ruthenium Isotopes

    E-print Network

    A. Nystrom; M. Thoennessen

    2011-02-11

    Currently, thirty-four yttrium, thirty-five zirconium, thirty-four niobium, thirty-five technetium, and thirty-eight ruthenium isotopes have been observed and the discovery of these isotopes is discussed here. For each isotope a brief synopsis of the first refereed publication, including the production and identification method, is presented.

  15. Phosphorus Recovery Using Zirconium-Loaded Saponified Orange Juice Residue

    NASA Astrophysics Data System (ADS)

    Harada, Hiroyuki; Kondo, Mitsunori; Biswas, Biplob K.; Ohura, Seichirou; Inoue, Katsutoshi; Ishikawa, Susumu; Kawakita, Hidetaka; Ohto, Keisuke

    Zirconium was immobilized to orange juice residue, to investigate the feasibility of using zirconium-loaded saponified orange juice residue (Zr-SOJR) for phosphorus recovery from secondary effluent and the extraction solution from incinerated sewage sludge ash by using H2SO4 and HCl. These had phosphorus concentrations of 68.2 mg/dm3 and 5.9 mg/dm3, respectively. The phosphorus removal rate secondary effluent increased with an increasing solid/liquid ratio in batch experiments. The adsorption capacity of Zr-SOJR was also compared with those obtained using a synthetic phosphorus solution and using zirconium-loaded ferrite. The prepared absorbent was effective for phosphorus removal and exhibited a reasonably high sorption capacity, twice that of zirconium ferrite. Secondary effluent was treated by packed column, and this reached break-through after 300 bed volumes. The results from phosphorous extraction from the ash indicate that can be treated with acid to efficiently recover phosphorous and thus can be absorbed by Zr-SOJR.

  16. Hydrogen pickup measurements in zirconium alloys: Relation to oxidation kinetics

    E-print Network

    Motta, Arthur T.

    Hydrogen pickup measurements in zirconium alloys: Relation to oxidation kinetics Adrien Couet a to reduce hydrogen pickup during operation, and the associated cladding degradation. The present study focuses on precisely and accurately measuring hydrogen pickup fraction for a set of alloys to specifically

  17. The application and comparison of 97Zr and 92Sr in the absolute determination of the contribution of power density and cladding activation in a VVER-1000 Mock-Up on the LR-0 Research Reactor

    NASA Astrophysics Data System (ADS)

    Koš?ál, Michal; Švadlenková, Marie; Mil?ák, Ján

    2014-02-01

    97Zr is a relatively high-yield fission product that can be used for zero reactor power determination. The technique is not widely used because in the case of reactors that use zirconium metal in the fuel cladding, it is not only a fission product but is also produced by activation. In an appropriately chosen time interval, results obtained using 97Zr can be compared to those of power determination performed using 92Sr. The knowledge of the ratio between fission-induced 97Zr and the portion of 97Zr activated in the cladding can be used not only for power-density determination but also as an important indication of fuel failures.

  18. Solution-based synthesis and processing of nanocrystalline zirconium diborides-based composites

    NASA Astrophysics Data System (ADS)

    Xie, Yanli

    Zirconium- and tantalum-based diborides, and diboride/carbide composites are of interest for ultra-high temperature applications requiring improved thermomechanical and thermochemical stability. This thesis focuses on the synthesis, processing and sintering of nanocrystalline powders with Zr- and Ta-based diboride/carbide/silicide compositions. A solution-based processing method was developed to prepare reactive mixtures that were precursors for ZrB2-based powders. The precursors reacted to form the ceramic powders after suitable pyrolysis and borothermal/carbothermal reduction heat treatments. Single-phase ZrB2 powders were prepared with initial composition of C/Zr = 4.8 and B/Zr = 3.0. ZrB2-based composite powders with ZrC, ZrO2, TaB2, TaC, SiC, TaSi 2 and B4C were prepared with particle sizes of 10-500 nm for different phases based SEM micrographs. The composite powders were highly sinterable with proper processing methods developed to avoid and remove oxide impurities. The relative densities of ZrB2/B4C, ZrB 2/TaB2, ZrB2/TaB2/B4C, ZrB 2/TaSi2 were in the range of 91%-97% after pressureless sintering at 2020°C for 1 h or 30 min.

  19. 50 CFR 300.97 - Inseason orders.

    Code of Federal Regulations, 2014 CFR

    2014-10-01

    ...INTERNATIONAL FISHERIES REGULATIONS Fraser River Sockeye and Pink Salmon Fisheries § 300.97 Inseason orders. (a) During...procedures section of the annual management measures for West Coast Salmon Fisheries, published in the Federal Register ; Treaty...

  20. 50 CFR 300.97 - Inseason orders.

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ...INTERNATIONAL FISHERIES REGULATIONS Fraser River Sockeye and Pink Salmon Fisheries § 300.97 Inseason orders. (a) During...procedures section of the annual management measures for West Coast Salmon Fisheries, published in the Federal Register ; Treaty...

  1. 50 CFR 300.97 - Inseason orders.

    Code of Federal Regulations, 2013 CFR

    2013-10-01

    ...INTERNATIONAL FISHERIES REGULATIONS Fraser River Sockeye and Pink Salmon Fisheries § 300.97 Inseason orders. (a) During...procedures section of the annual management measures for West Coast Salmon Fisheries, published in the Federal Register ; Treaty...

  2. 50 CFR 300.97 - Inseason orders.

    Code of Federal Regulations, 2011 CFR

    2011-10-01

    ...INTERNATIONAL FISHERIES REGULATIONS Fraser River Sockeye and Pink Salmon Fisheries § 300.97 Inseason orders. (a) During...procedures section of the annual management measures for West Coast Salmon Fisheries, published in the Federal Register ; Treaty...

  3. 50 CFR 300.97 - Inseason orders.

    Code of Federal Regulations, 2012 CFR

    2012-10-01

    ...INTERNATIONAL FISHERIES REGULATIONS Fraser River Sockeye and Pink Salmon Fisheries § 300.97 Inseason orders. (a) During...procedures section of the annual management measures for West Coast Salmon Fisheries, published in the Federal Register ; Treaty...

  4. 40 CFR 97.201 - Purpose.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ...NOX AND SO2 TRADING PROGRAMS CAIR SO2 Trading Program General Provisions § 97.201 Purpose. This subpart and subparts BBB through III set forth the general provisions and the designated representative, permitting, allowance, monitoring,...

  5. 47 CFR 97.119 - Station identification.

    Code of Federal Regulations, 2013 CFR

    2013-10-01

    ...RADIO SERVICES AMATEUR RADIO SERVICE Station Operation Standards § 97.119 Station identification. (a) Each amateur station, except a space station or telecommand station, must transmit its assigned call sign on its...

  6. 47 CFR 97.119 - Station identification.

    Code of Federal Regulations, 2011 CFR

    2011-10-01

    ...RADIO SERVICES AMATEUR RADIO SERVICE Station Operation Standards § 97.119 Station identification. (a) Each amateur station, except a space station or telecommand station, must transmit its assigned call sign on its...

  7. 47 CFR 97.119 - Station identification.

    Code of Federal Regulations, 2012 CFR

    2012-10-01

    ...RADIO SERVICES AMATEUR RADIO SERVICE Station Operation Standards § 97.119 Station identification. (a) Each amateur station, except a space station or telecommand station, must transmit its assigned call sign on its...

  8. 47 CFR 97.119 - Station identification.

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ...RADIO SERVICES AMATEUR RADIO SERVICE Station Operation Standards § 97.119 Station identification. (a) Each amateur station, except a space station or telecommand station, must transmit its assigned call sign on its...

  9. 40 CFR 97.355 - Banking.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ...TRADING PROGRAMS CAIR NOX Ozone Season Allowance Tracking System § 97.355 Banking. (a) CAIR NOX Ozone Season allowances may be banked for future...section. (b) Any CAIR NOX Ozone Season allowance that is held in a...

  10. 40 CFR 97.355 - Banking.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ...TRADING PROGRAMS CAIR NOX Ozone Season Allowance Tracking System § 97.355 Banking. (a) CAIR NOX Ozone Season allowances may be banked for future...section. (b) Any CAIR NOX Ozone Season allowance that is held in a...

  11. 40 CFR 97.361 - EPA recordation.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ...SO2 TRADING PROGRAMS CAIR NOX Ozone Season Allowance Transfers § 97.361 EPA...section) of receiving a CAIR NOX Ozone Season allowance transfer, the Administrator will record a CAIR NOX Ozone Season allowance transfer by moving each...

  12. 40 CFR 97.361 - EPA recordation.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ...SO2 TRADING PROGRAMS CAIR NOX Ozone Season Allowance Transfers § 97.361 EPA...section) of receiving a CAIR NOX Ozone Season allowance transfer, the Administrator will record a CAIR NOX Ozone Season allowance transfer by moving each...

  13. 34 CFR 97.107 - IRB membership.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ...Policy for the Protection of Human Subjects (Basic ED Policy for Protection of Human Research Subjects) § 97...safeguarding the rights and welfare of human subjects. In addition...of qualified persons of both sexes, so long as no selection...

  14. 34 CFR 97.107 - IRB membership.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ...Policy for the Protection of Human Subjects (Basic ED Policy for Protection of Human Research Subjects) § 97...safeguarding the rights and welfare of human subjects. In addition...of qualified persons of both sexes, so long as no selection...

  15. 34 CFR 97.107 - IRB membership.

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ...Policy for the Protection of Human Subjects (Basic ED Policy for Protection of Human Research Subjects) § 97...safeguarding the rights and welfare of human subjects. In addition...of qualified persons of both sexes, so long as no selection...

  16. 46 CFR 97.15-1 - Application.

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ...Shipping COAST GUARD, DEPARTMENT OF HOMELAND SECURITY (CONTINUED) CARGO AND MISCELLANEOUS VESSELS OPERATIONS Tests, Drills, and Inspections § 97.15-1 Application. (a) Except as specifically noted, the provisions of this subpart...

  17. 40 CFR 97.13 - Account certificate of representation.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... false Account certificate of representation. 97.13 Section 97.13 ...97.13 Account certificate of representation. (a) A complete account certificate of representation for a NOX authorized account...

  18. 40 CFR 97.13 - Account certificate of representation.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... false Account certificate of representation. 97.13 Section 97.13 ...97.13 Account certificate of representation. (a) A complete account certificate of representation for a NOX authorized account...

  19. 40 CFR 97.13 - Account certificate of representation.

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... false Account certificate of representation. 97.13 Section 97.13 ...97.13 Account certificate of representation. (a) A complete account certificate of representation for a NOX authorized account...

  20. 40 CFR 97.13 - Account certificate of representation.

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... false Account certificate of representation. 97.13 Section 97.13 ...97.13 Account certificate of representation. (a) A complete account certificate of representation for a NOX authorized account...

  1. 40 CFR 97.13 - Account certificate of representation.

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... false Account certificate of representation. 97.13 Section 97.13 ...97.13 Account certificate of representation. (a) A complete account certificate of representation for a NOX authorized account...

  2. 34 CFR 97.109 - IRB review of research.

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... 2014-07-01 false IRB review of research. 97.109 Section 97.109 Education...Basic ED Policy for Protection of Human Research Subjects) § 97.109 IRB review of research. (a) An IRB shall review and...

  3. 34 CFR 97.109 - IRB review of research.

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... 2013-07-01 false IRB review of research. 97.109 Section 97.109 Education...Basic ED Policy for Protection of Human Research Subjects) § 97.109 IRB review of research. (a) An IRB shall review and...

  4. 34 CFR 97.109 - IRB review of research.

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... 2012-07-01 false IRB review of research. 97.109 Section 97.109 Education...Basic ED Policy for Protection of Human Research Subjects) § 97.109 IRB review of research. (a) An IRB shall review and...

  5. 47 CFR 97.115 - Third party communications.

    Code of Federal Regulations, 2011 CFR

    2011-10-01

    ...2011-10-01 false Third party communications. 97.115 Section 97.115 Telecommunication FEDERAL COMMUNICATIONS COMMISSION (CONTINUED) SAFETY...Standards § 97.115 Third party communications. (a) An amateur...

  6. 47 CFR 97.115 - Third party communications.

    Code of Federal Regulations, 2013 CFR

    2013-10-01

    ...2013-10-01 false Third party communications. 97.115 Section 97.115 Telecommunication FEDERAL COMMUNICATIONS COMMISSION (CONTINUED) SAFETY...Standards § 97.115 Third party communications. (a) An amateur...

  7. 47 CFR 97.115 - Third party communications.

    Code of Federal Regulations, 2012 CFR

    2012-10-01

    ...2012-10-01 false Third party communications. 97.115 Section 97.115 Telecommunication FEDERAL COMMUNICATIONS COMMISSION (CONTINUED) SAFETY...Standards § 97.115 Third party communications. (a) An amateur...

  8. 47 CFR 97.115 - Third party communications.

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ...2010-10-01 false Third party communications. 97.115 Section 97.115 Telecommunication FEDERAL COMMUNICATIONS COMMISSION (CONTINUED) SAFETY...Standards § 97.115 Third party communications. (a) An amateur...

  9. 34 CFR 97.109 - IRB review of research.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... 2011-07-01 false IRB review of research. 97.109 Section 97.109 Education...Basic ED Policy for Protection of Human Research Subjects) § 97.109 IRB review of research. (a) An IRB shall review and...

  10. 34 CFR 97.109 - IRB review of research.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... 2010-07-01 false IRB review of research. 97.109 Section 97.109 Education...Basic ED Policy for Protection of Human Research Subjects) § 97.109 IRB review of research. (a) An IRB shall review and...

  11. 47 CFR 97.9 - Operator license grant.

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ...Operator license grant. 97.9 Section 97.9 Telecommunication FEDERAL...General Provisions § 97.9 Operator license grant. (a) The classes of amateur operator license...on the license grant. (b) The person named in an...

  12. 46 CFR 98.25-97 - Nondestructive testing.

    Code of Federal Regulations, 2013 CFR

    2013-10-01

    ...2013-10-01 2013-10-01 false Nondestructive testing. 98.25-97 Section 98.25-97...Anhydrous Ammonia in Bulk § 98.25-97 Nondestructive testing. (a) Before nondestructive testing may be conducted to meet §...

  13. 46 CFR 98.25-97 - Nondestructive testing.

    Code of Federal Regulations, 2014 CFR

    2014-10-01

    ...2014-10-01 2014-10-01 false Nondestructive testing. 98.25-97 Section 98.25-97...Anhydrous Ammonia in Bulk § 98.25-97 Nondestructive testing. (a) Before nondestructive testing may be conducted to meet §...

  14. 46 CFR 98.25-97 - Nondestructive testing.

    Code of Federal Regulations, 2011 CFR

    2011-10-01

    ...2011-10-01 2011-10-01 false Nondestructive testing. 98.25-97 Section 98.25-97...Anhydrous Ammonia in Bulk § 98.25-97 Nondestructive testing. (a) Before nondestructive testing may be conducted to meet §...

  15. 46 CFR 98.25-97 - Nondestructive testing.

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ...2010-10-01 2010-10-01 false Nondestructive testing. 98.25-97 Section 98.25-97...Anhydrous Ammonia in Bulk § 98.25-97 Nondestructive testing. (a) Before nondestructive testing may be conducted to meet §...

  16. 46 CFR 98.25-97 - Nondestructive testing.

    Code of Federal Regulations, 2012 CFR

    2012-10-01

    ...2012-10-01 2012-10-01 false Nondestructive testing. 98.25-97 Section 98.25-97...Anhydrous Ammonia in Bulk § 98.25-97 Nondestructive testing. (a) Before nondestructive testing may be conducted to meet §...

  17. Nuclear-grade zirconium prepared by combining combustion synthesis with molten-salt electrorefining technique

    NASA Astrophysics Data System (ADS)

    Li, Hui; Nersisyan, Hayk H.; Park, Kyung-Tae; Park, Sung-Bin; Kim, Jeong-Guk; Lee, Jeong-Min; Lee, Jong-Hyeon

    2011-06-01

    Zirconium has a low absorption cross-section for neutrons, which makes it an ideal material for use in nuclear reactor applications. However, hafnium typically contained in zirconium causes it to be far less useful for nuclear reactor materials because of its high neutron-absorbing properties. In the present study, a novel effective method has been developed for the production of hafnium-free zirconium. The process includes two main stages: magnesio-thermic reduction of ZrSiO 4 under a combustion mode, to produce zirconium silicide (ZrSi), and recovery of hafnium-free zirconium by molten-salt electrorefining. It was found that, depending on the electrorefining procedure, it is possible to produce zirconium powder with a low hafnium content: 70 ppm, determined by ICP-AES analysis.

  18. The effect of zirconium on the cyclic oxidation of NiCrAl alloys

    NASA Technical Reports Server (NTRS)

    Barrett, C. A.; Khan, A. S.; Lowell, C. E.

    1981-01-01

    This paper examines results with cyclic oxidation tests of Ni(9-20) Cr(15-30) Al-(x)Zr alloys carried out at 1100 C and 1200 C in static air. The concentration of zirconium varies from 0 to 0.63 atomic percent. Significant aluminum penetration is found in metallographic and electron microscopic examination of oxidized surfaces. Small amounts of zirconium lead to minimal penetration, and with increased zirconium content pronounced oxide penetration is observed.

  19. Alumina zirconium ceramics synthesis by selective laser sintering/melting

    NASA Astrophysics Data System (ADS)

    Shishkovsky, I.; Yadroitsev, I.; Bertrand, Ph.; Smurov, I.

    2007-12-01

    In the present paper, porous refractory ceramics synthesized by selective laser sintering/melting from a mixture of zirconium dioxide, aluminum and/or alumina powders are subjected to optical metallography and X-ray analysis to study their microstructure and phase composition depending on the laser processing parameters. It is shown that high-speed laser sintering in air yields ceramics with dense structure and a uniform distribution of the stabilizing phases. The obtained ceramic-matrix composites may be used as thermal and electrical insulators and wear resistant coating in solid oxide fuel cells, crucibles, heating elements, medical tools. The possibility to reinforce refractory ceramics by laser synthesis is shown on the example of tetragonal dioxide of zirconium with hardened micro-inclusion of Al 2O 3. By applying finely dispersed Y 2O 3 powder inclusions, the type of the ceramic structure is significantly changed.

  20. Alternative Processing of High Temperature Hafnium and Zirconium Based Materials

    NASA Technical Reports Server (NTRS)

    Gasch, Matthew; Gusman, Michael; Ellerby, Don; Irby, Edward; Johnson, Sylvia M.

    2003-01-01

    The behavior of refractory hafnium and zirconium based materials are being investigated at NASA Ames as part of ongoing research aimed at developing superior heat resistant materials for aerospace applications. Hafnium and zirconium diboride based materials have shown high temperature capabilities in simulated reentry environments indicating that these materials may successfully operate as reusable oxidation resistant components for leading edge applications. Due to the refractory nature of these materials, processing of fine-grained uniform microstructures poses a number of challenges. To better understand the process-property-microstructure relationship, processing of these materials has been carried out with conventional hot pressing in addition to the novel approach of Spark Plasma Sintering (SPS). The two processing methods are compared and contrasted in an evaluation of the sintering behavior of high temperature diboride based materials and preliminary physical and mechanical properties are presented.

  1. Modelling zirconium hydrides using the special quasirandom structure approach.

    PubMed

    Wang, H; Chroneos, A; Jiang, C; Schwingenschlögl, U

    2013-05-28

    The study of the structure and properties of zirconium hydrides is important for understanding the embrittlement of zirconium alloys used as cladding in light water nuclear reactors. Simulation of the defect processes is complicated due to the random distribution of the hydrogen atoms. We propose the use of the special quasirandom structure approach as a computationally efficient way to describe this random distribution. We have generated six special quasirandom structure cells based on face centered cubic and face centered tetragonal unit cells to describe ZrH(2-x) (x = 0.25-0.5). Using density functional theory calculations we investigate the mechanical properties, stability, and electronic structure of the alloys. PMID:23588997

  2. ZIRCONIUM AND HAFNIUM (Data in metric tons, unless noted)

    E-print Network

    companies as well. Zirconia (ZrO2) was produced from zircon sand at plants in Alabama, New Hampshire, New in superalloys. Salient Statistics--United States: 1991 1992 1993 1994 1995e Production: Zircon (ZrO2 content)1 67,000 70,300 W W W Imports: Zirconium, ores and concentrates (ZrO2 content) 23,200 24,300 45,500 53

  3. ZIRCONIUM AND HAFNIUM (Data in metric tons, unless otherwise noted)

    E-print Network

    . Zirconia (ZrO2) was produced from zircon sand at plants in Alabama, New Hampshire, New York, Ohio in superalloys. Salient Statistics--United States: 1999 2000 2001 2002 2003e Production, zircon (ZrO2 content)1 100,000 100,000 100,000 100,000 100,000 Imports: Zirconium, ores and concentrates (ZrO2 content) 37

  4. Cesium Adsorption on the ZIRCONIUM\\/OXYGEN\\/TUNGSTEN(100) Surface

    Microsoft Academic Search

    Hsiung-Ku. Chen

    1983-01-01

    Interest in zirconium covered tungsten as an electrode material has been stimulated by recent work on the model surface Zr\\/O\\/W(100). This surface has been shown to have an effective thermionic work function of (TURN) 2.6 eV, when properly prepared, with very low volatility and excellent thermal stability. For advanced thermionic converter applications and for proposed future nuclear electric propulsion systems,

  5. Synthesis and characterization of titanium and zirconium oxynitride coatings

    Microsoft Academic Search

    A. Rizzo; M. A. Signore; L. Mirenghi; T. Di Luccio

    2009-01-01

    Thin films of zirconium oxynitride (ZrNO) and titanium oxynitride (TiNO) have been deposited onto Si(100) substrates at room temperature by radiofrequency magnetron sputtering in an argon–oxygen–nitrogen atmosphere. Single oxynitride layers have been stacked to obtain a multilayer structure. The film structure has been determined by X-ray diffraction while compositional analysis has been performed by X-photoelectrons spectroscopy. Structural analysis has shown

  6. Oxidation characteristics of molybdenum-zirconium oxide cermets

    NASA Technical Reports Server (NTRS)

    Heitzinger, B.

    1984-01-01

    The oxidation of molybdenum is affected by the factors of temperature, the oxygen pressure in the oxidizing atmosphere, and the time of exposure. Studies of the oxidation characteristics of Mo show that the oxidation rate increases strongly when the temperature exceeds 600 C. Investigations of the behavior of cermets with various percentages of zirconium oxide are discussed, taking into account oxidation conditions at temperatures under and above the melting point of molybdenum trioxide.

  7. Ferrier rearrangement promoted by an electrochemically generated zirconium catalyst.

    PubMed

    Stevanovi?, Dragana; Pejovi?, Anka; Damljanovi?, Ivan; Mini?, Aleksandra; Bogdanovi?, Goran A; Vuki?evi?, Mirjana; Radulovi?, Niko S; Vuki?evi?, Rastko D

    2015-04-30

    In situ generated zirconium catalyst from a sacrificial zirconium anode was successfully applied to promote Ferrier rearrangement of 3,4,5-tri-O-acetyl-d-glucal and 6-deoxy-3,4-di-O-acetyl-l-glucal (3,4-di-O-acetyl-l-rhamnal) in the presence of three thiols and eleven thiophenols as nucleophiles. A simple constant current electrolysis (20 mA, 0.4 F mol(-1)) of an acetonitrile solution of lithium perchlorate (0.1 M) containing the corresponding glycal and S-nucleophiles, using a zirconium anode and a platinum cathode resulted in the successful synthesis of the corresponding 2,3-unsaturated peracetylated thioglycosides (with an average anomer ratio ?/?=4.129 in the case of peracetylated d-glucal and 8.740 in the case of l-rhamnal). The same procedure proved to be appropriate in synthesizing dihydropyran derivatives ('C-glycosides') using allyltrimethylsilane as the nucleophile (only '?-anomers' were obtained). All new compounds were fully characterized by spectral data, whereas single-crystal X-ray analysis was performed for two thioglycosides. PMID:25746956

  8. Laves intermetallics in stainless steel-zirconium alloys

    SciTech Connect

    Abraham, D.P.; McDeavitt, S.M.; Richardson, J.W. Jr.

    1997-05-01

    Laves intermetallics have a significant effect on properties of metal waste forms being developed at Argonne National Laboratory. These waste forms are stainless steel-zirconium alloys that will contain radioactive metal isotopes isolated from spent nuclear fuel by electrometallurgical treatment. The baseline waste form composition for stainless steel-clad fuels is stainless steel-15 wt.% zirconium (SS-15Zr). This article presents results of neutron diffraction measurements, heat-treatment studies and mechanical testing on SS-15Zr alloys. The Laves intermetallics in these alloys, labeled Zr(Fe,Cr,Ni){sub 2+x}, have both C36 and C15 crystal structures. A fraction of these intermetallics transform into (Fe,Cr,Ni){sub 23}Zr{sub 6} during high-temperature annealing; the authors have proposed a mechanism for this transformation. The SS-15Zr alloys show virtually no elongation in uniaxial tension, but exhibit good strength and ductility in compression tests. This article also presents neutron diffraction and microstructural data for a stainless steel-42 wt.% zirconium (SS-42Zr) alloy.

  9. Nuclear Engineering and Design/Fusion 2 (1985) 97-110 97 North-Holland, Amsterdam

    E-print Network

    Ghoniem, Nasr M.

    Nuclear Engineering and Design/Fusion 2 (1985) 97-110 97 North-Holland, Amsterdam DEVELOPMENT OF DESIGN EQUATIONS FOR FERRITIC ALLOYS IN FUSION REACTORS Robert J. AMODEO and Nasr M. GHONIEM Fusion in determining the lifetime of materials in the fusion environment [1]. Equations which describe the swelling

  10. NASA/CR-97-206268 ICASE Report No. 97-68

    E-print Network

    Jameson, Antony

    NASA/CR-97-206268 ICASE Report No. 97-68 _th ,NNIVERSARY Essential Elements of Computational Algorithms for Aerodynamic Analysis and Design Antony Jameson December 1997 #12;The NASA STI Program Off'we... in Profile Since its founding, NASA has been dedicated to the advancement of aeronautics and space science

  11. hepph/9705202 CLNS 97/1468, HUTP97/A016, NUB 3138

    E-print Network

    of the phenomenological properties of this model and the closely related SO(10) string model. They have 5 righthep­ph/9705202 1 May 1997 CLNS 97/1468, HUTP­97/A016, NUB 3138 Phenomenology of 3­Family Grand Unified String Models Zurab Kakushadze 1;2 \\Lambda , Gary Shiu 3y , S.­H. Henry Tye 3z , Yan Vtorov

  12. Inhibitors of the AAA+ Chaperone p97.

    PubMed

    Chapman, Eli; Maksim, Nick; de la Cruz, Fabian; La Clair, James J

    2015-01-01

    It is remarkable that a pathway as ubiquitous as protein quality control can be targeted to treat cancer. Bortezomib, an inhibitor of the proteasome, was first approved by the US Food and Drug Administration (FDA) more than 10 years ago to treat refractory myeloma and later extended to lymphoma. Its use has increased the survival rate of myeloma patients by as much as three years. This success was followed with the recent accelerated approval of the natural product derived proteasome inhibitor carfilzomib (Kyprolis®), which is used to treat patients with bortezomib-resistant multiple myeloma. The success of these two drugs has validated protein quality control as a viable target to fight select cancers, but begs the question why are proteasome inhibitors limited to lymphoma and myeloma? More recently, these limitations have encouraged the search for additional targets within the protein quality control system that might offer heightened cancer cell specificity, enhanced clinical utility, a lower rate of resistance, reduced toxicity, and mitigated side effects. One promising target is p97, an ATPase associated with various cellular activities (AAA+) chaperone. p97 figures prominently in protein quality control as well as serving a variety of other cellular functions associated with cancer. More than a decade ago, it was determined that up-regulation of p97 in many forms of cancer correlates with a poor clinical outcome. Since these initial discoveries, a mechanistic explanation for this observation has been partially illuminated, but details are lacking. Understandably, given this clinical correlation, myriad roles within the cell, and its importance in protein quality control, p97 has emerged as a potential therapeutic target. This review provides an overview of efforts towards the discovery of small molecule inhibitors of p97, offering a synopsis of efforts that parallel the excellent reviews that currently exist on p97 structure, function, and physiology. PMID:25685910

  13. DlgS97/SAP97, a Neuronal Isoform of Discs Large, Regulates Ethanol Tolerance

    PubMed Central

    Kong, Eric C.; Slawson, Justin B.; Griffith, Leslie C.; Takamiya, Kogo; Huganir, Richard L.; Margolis, Ben; Heberlein, Ulrike

    2012-01-01

    From a genetic screen for Drosophila melanogaster mutants with altered ethanol tolerance, we identified intolerant (intol), a novel allele of discs large 1 (dlg1). Dlg1 encodes Discs Large 1, a MAGUK (Membrane Associated Guanylate Kinase) family member that is the highly conserved homolog of mammalian PSD-95 and SAP97. The intol mutation disrupted specifically the expression of DlgS97, a SAP97 homolog, and one of two major protein isoforms encoded by dlg1 via alternative splicing. Expression of the major isoform, DlgA, a PSD-95 homolog, appeared unaffected. Ethanol tolerance in the intol mutant could be partially restored by transgenic expression of DlgS97, but not DlgA, in specific neurons of the fly’s brain. Based on co-immunoprecipitation, DlgS97 forms a complex with N-methyl-D-aspartate (NMDA) receptors, a known target of ethanol. Consistent with these observations, flies expressing reduced levels of the essential NMDA receptor subunit dNR1 also showed reduced ethanol tolerance, as did mutants in the gene calcium/calmodulin-dependent protein kinase (caki), encoding the fly homolog of mammalian CASK, a known binding partner of DlgS97. Lastly, mice in which SAP97, the mammalian homolog of DlgS97, was conditionally deleted in adults failed to develop rapid tolerance to ethanol’s sedative/hypnotic effects. We propose that DlgS97/SAP97 plays an important and conserved role in the development of tolerance to ethanol via NMDA receptor-mediated synaptic plasticity. PMID:23145041

  14. 40 CFR 97.506 - Standard requirements.

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ...CAIR NOX AND SO2 TRADING PROGRAMS TR NOX Ozone Season Trading Program § 97.506 Standard requirements...designated representative, of each TR NOX Ozone Season source and each TR NOX Ozone Season unit at the source shall comply with the...

  15. 40 CFR 97.506 - Standard requirements.

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ...CAIR NOX AND SO2 TRADING PROGRAMS TR NOX Ozone Season Trading Program § 97.506 Standard requirements...designated representative, of each TR NOX Ozone Season source and each TR NOX Ozone Season unit at the source shall comply with the...

  16. 40 CFR 97.506 - Standard requirements.

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ...CAIR NOX AND SO2 TRADING PROGRAMS TR NOX Ozone Season Trading Program § 97.506 Standard requirements...designated representative, of each TR NOX Ozone Season source and each TR NOX Ozone Season unit at the source shall comply with the...

  17. 40 CFR 97.370 - General requirements.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ...or operator of a CAIR NOX Ozone Season unit shall disrupt...or operator of a CAIR NOX Ozone Season unit shall retire...under § 97.305 that is in effect; (ii) The owner or...or operator of a CAIR NOX Ozone Season unit is subject to...

  18. 40 CFR 97.281 - General.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ...through 97.208, and subparts BBB and CCC and subparts FFF through HHH of this part, a CAIR SO2 opt-in unit shall be treated as...applying, as provided in this subpart, the requirements of subpart HHH of this part to a unit for which a CAIR opt-in permit...

  19. MDR's Enrollment Comparison Report 1996/97.

    ERIC Educational Resources Information Center

    Market Data Retrieval, Inc., Shelton, CT.

    This compilation of tables presents information on public school enrollment for the 1996-97 school year with comparative information for the 1995-1996 school year. Tables present information on school enrollments by state, with 1-year comparisons of total state enrollments for the two school years in alphabetical order, in descending order by…

  20. Separation of Zirconium from Uranium in U-Zr Alloys Using a Chlorination Process

    E-print Network

    Parkison, Adam J

    2013-06-04

    ........................................................... 12 2.2.1 Chloride Processing ................................................................................... 13 2.2.2 Fluoride Processing .................................................................................... 15 2.2.3 Bromide.... ................................ 10 Figure 3: Zirconium crystal bar process flow diagram. .............................................. 19 Figure 4: Examples of crystal bar produced using the iodide volatilization process. (A) Titanium. (B) Zirconium. (C) Hafnium. (D...

  1. Lithium aluminate/zirconium material useful in the production of tritium

    DOEpatents

    Cawley, William E. (Richland, WA); Trapp, Turner J. (Richland, WA)

    1984-10-09

    A composition is described useful in the production of tritium in a nuclear eactor. Lithium aluminate particles are dispersed in a matrix of zirconium. Tritium produced by the reactor of neutrons with the lithium are absorbed by the zirconium, thereby decreasing gas pressure within capsules carrying the material.

  2. Manganese porphyrin multilayer films assembled on ITO electrodes via zirconium phosphonate chemistry: chemical and electrochemical

    E-print Network

    Manganese porphyrin multilayer films assembled on ITO electrodes via zirconium phosphonate University, 2145 Sheridan Road, Evanston, IL 60208-3113 A supported manganese porphyrin-based oxidation)porphyrinato] manganese(III) chloride (2) and zirconium(IV) ions on indium­tin oxide electrodes. This assembly technique

  3. Zirconium carbide as an electrocatalyst for the chromous-chromic redox couple

    NASA Technical Reports Server (NTRS)

    Gahn, R. F.; Reid, M. A.; Yang, C. Y. (inventors)

    1981-01-01

    Zirconium carbide is used as a catalyst in a REDOX cell for the oxidation of chromous ions to chromic ions and for the reduction of chromic ions to chromous ions. The zirconium carbide is coated on an inert electronically conductive electrode which is present in the anode fluid of the cell.

  4. Zirconium oxidation under high energy heavy ion irradiation N. Brerd, A. Chevarier, N. Moncoffre, H. Jaffrezic,

    E-print Network

    Paris-Sud XI, Université de

    Zirconium oxidation under high energy heavy ion irradiation N. Bérerd, A. Chevarier, N. Moncoffre This paper concerns the study of zirconium oxidation under irradiation with high energetic Xe ions oxidation data. 1 #12;I. INTRODUCTION This paper deals with the influence of heavy ion irradiation

  5. Lithium aluminate/zirconium material useful in the production of tritium

    DOEpatents

    Cawley, W.E.; Trapp, T.J.

    1984-10-09

    A composition is described useful in the production of tritium in a nuclear reactor. Lithium aluminate particles are dispersed in a matrix of zirconium. Tritium produced by the reactor of neutrons with the lithium are absorbed by the zirconium, thereby decreasing gas pressure within capsules carrying the material.

  6. Solid-State Coexistance of (Zr12) and (Zr6) Zirconium Oxocarboxylate Clusters

    SciTech Connect

    Malaestean, Lurie [RWTH Aachen University; Alici, Meliha Kutluca [RWTH Aachen University; Besson, Claire [RWTH Aachen University; Ellern, Arkady [Ames Laboratory; Kogerler, Paul [RWTH Aachen University

    2013-10-30

    Ligand metathesis, Co(II) coordination, and partial condensation reactions of an archetypal {Zr6} zirconium oxocarboxylate cluster result in the first example of the coexistence of the distinct zirconium oxide frameworks {Zr6O8} and {Zr12O22}. Even minor modifications to the reaction conditions push this apparent equilibrium towards the {Zr6O8}-based product.

  7. Solid-state coexistence of {Zr12} and {Zr6} zirconium oxocarboxylate clusters

    SciTech Connect

    Malaestean, Iurie L. [RWTH Aachen University; Alici, Meliha Kutluca [RWTH Aachen University; Besson, Claire [RWTH Aachen University; Ellern, Arkady [Ames Laboratory; Kogerler, Paul [RWTH Aachen University

    2013-10-30

    Ligand metathesis, Co(II) coordination, and partial condensation reactions of an archetypal {Zr6} zirconium oxocarboxylate cluster result in the first example of the coexistence of the distinct zirconium oxide frameworks {Zr6O8} and {Zr12O22}. Even minor modifications to the reaction conditions push this apparent equilibrium towards the {Zr6O8}-based product.

  8. Predicting the equilibria of point defects in zirconium oxide : a route to understand the corrosion and hydrogen pickup of zirconium alloys

    E-print Network

    Youssef, Mostafa Youssef Mahmoud

    2014-01-01

    The performance of zirconium alloys in nuclear reactors is compromised by corrosion and hydrogen pickup. The thermodynamics and kinetics of these two processes are governed by the behavior of point defects in the ZrO? layer ...

  9. Zirconium Determination by Cooling Curve Analysis during the Pyroprocessing of Used Nuclear Fuel

    SciTech Connect

    B.R. Westphal; J.C. Price; K.J. Bateman; K.C. Marsden

    2001-03-01

    An alternative method to sampling and chemical analyses has been developed to monitor the concentration of zirconium in real-time during the casting of uranium products from the pyroprocessing of used nuclear fuel. The method utilizes the solidification characteristics of the uranium products to determine zirconium levels based on standard cooling curve analyses and established binary phase diagram data. Numerous uranium products have been analyzed for their zirconium content and compared against measured zirconium data. From this data, a relationship was derived that incorporates the mass dependency of the uranium products since solidification monitoring is performed external to the melt. Using the relationship, a reasonable fit of calculated to measured zirconium content was established considering the errors in the system.

  10. Effects of intermetallic particles on the SCC initiation of zirconium alloys

    NASA Astrophysics Data System (ADS)

    Kubo, T.; Wakashima, Y.; Imahashi, H.; Nagai, M.

    1985-06-01

    In order to investigate effects of intermetallic particles on SCC initiation of zirconium alloys, tensile tests were conducted in an iodine atmosphere using zirconium plates with different amounts of impurities, and Zircaloy-2 plates. SCC susceptibility of zirconium increased significantly with its iron content. Even small amounts of iron could form the intermetallic compound ZrFe 2 whose particle size and number increased with iron content. In the case of Zircaloy-2, two different types of ternary compounds were detected, namely Zr(CrFe) 2 and Zr 2(NiFe). Metallographic examinations showed that the particles located at grain boundaries were important sites of SCC initiation in zirconium alloys. The initiation probability increased significantly with the amount of the particles, which supported the strong correlation between SCC susceptibility of zirconium and its iron content.

  11. A simple spectrophotometric method for determination of zirconium or hafnium in selected molybdenum-base alloys

    NASA Technical Reports Server (NTRS)

    Dupraw, W. A.

    1972-01-01

    A simple analytical procedure is described for accurately and precisely determining the zirconium or hafnium content of molybdenum-base alloys. The procedure is based on the reaction of the reagent Arsenazo III with zirconium or hafnium in strong hydrochloric acid solution. The colored complexes of zirconium or hafnium are formed in the presence of molybdenum. Titanium or rhenium in the alloy have no adverse effect on the zirconium or hafnium complex at the following levels in the selected aliquot: Mo, 10 mg; Re, 10 mg; Ti, 1 mg. The spectrophotometric measurement of the zirconium or hafnium complex is accomplished without prior separation with a relative standard deviation of 1.3 to 2.7 percent.

  12. Preparation and properties of uniform mixed and coated colloidal particles. Part 5. Zirconium compounds

    SciTech Connect

    Alken, B.; Hsu, W.P.; Matijevic, E.

    1990-01-01

    Colloidal dispersions of uniform spherical particles by zirconium basic sulphate and zirconium oxy-basic carbonate were prepared by ageing zirconium sulphate solutions at elevated temperatures in the presence of urea. Different chemical compositions of the above products resulted when the ageing temperature was altered. Depending on the nature of the original solids, calcination at 800 C resulted in the formation of tetragonal or monoclinic zirconia. Under certain conditions a mixed phase, including cubic zirconia, has also been identified. The particle morphology was retained during these transformations. Coprecipitation in mixed solutions of zirconium and yttrium salts aged at 80 C yielded composite spherical particles of basic carbonate with a zirconium to yttrium ratio of the solid similar to that used in the initial solution.

  13. Thermodynamic study of the zirconium-aluminum system

    SciTech Connect

    Kematick, R.J.; Franzen, H.F.

    1984-09-01

    The heats of formation of the zirconium-aluminum intermetallic compounds ZrAl/sub 3/, ZrAl/sub 2/, Zr/sub 2/Al/sub 3/, ZrAl, Zr/sub 5/Al/sub 4/, Zr/sub 3/Al/sub 2/, Zr/sub 5/Al/sub 3/, and the solid solution of aluminum in bcc zirconium have been studied using a Knudsen cell mass spectrometric technique. The high temperature compound Zr/sub 5/Al/sub 4/ was identified in the residue of some of these experiments and this led to further heat treatment/X-ray diffraction experiments which indicated that Zr/sub 4/Al/sub 3/, previously reported to form from the melt, decomposes in the solid state at temperature in excess of 1050/sup 0/C. By measuring aluminum vapor pressures over the two-phase ranges of the system from 0 < X/sub Al/ < 0.75 the enthalpy changes for the decomposition reactions were determined by second- and third-law methods, and these were used along with the measured vapor pressure of aluminum over the solid solution of aluminum in bcc zirconium to derive the enthalpies of formation of the intermetallic phases (in kcal/mole): ZrAl/sub 3/, -38.96; ZrAl/sub 2/, -32.86; Zr/sub 2/Al/sub 3/, -56.12; ZrAl, -21.36; Zr/sub 5/Al/sub 4/, -93.76; Zr/sub 3/Al/sub 2/, -48.78; Zr/sub 5/Al/sub 3/, -74.57. 21 references, 4 figures, 4 tables.

  14. The abundances of zirconium and hafnium in the solar system

    NASA Technical Reports Server (NTRS)

    Ganapathy, R.; Papia, G. M.; Grossman, L.

    1976-01-01

    The concentrations of zirconium and hafnium have been determined in the Orgueil, Murchison, Allende, Bruderheim, and Alais meteorites by radiochemical neutron activation analysis. The mean Zr/Hf weight ratio in the first four of these meteorites is 31.3 (plus or minus 2.2), indicating no major fractionation of Zr from Hf. Alais contains anomalously high amounts of many refractory lithophile elements, including Zr and Hf. Orgueil contains 3.1 ppm Zr and 0.11 ppm Hf, corresponding to 9.0 and 0.16 atoms, respectively, relative to 1 million Si atoms.

  15. Mechanical Properties of Continuous Fiber Reinforced Zirconium Diboride Matrix Composites

    NASA Technical Reports Server (NTRS)

    Stuffle, Kevin; Creegan, Peter; Nowell, Steven; Bull, Jeffrey D.; Rasky, Daniel J. (Technical Monitor)

    1995-01-01

    Continuous fiber reinforced zirconium diboride matrix composites, SCS-9a-(RBSiCZrB2)matrix, are being developed for leading edge, rocket nozzle and turbine engine applications. Recently, the composite materials have been characterized for tensile properties to 1250 C, the highest temperature tested. The tensile properties are fiber dominated as the matrix is microcracked on fabrication, but favorable failure characteristic are observed. Compression and shear mechanical testing results will be reported if completed. The effects of fiber volume fraction and matrix density on mechanical properties will be discussed. The target applications of the materials will be discussed. Specific testing being performed towards qualification for these applications will be included.

  16. Rapid and cost-effective method for synthesizing zirconium silicides

    Microsoft Academic Search

    Il-Je Cho; Kyung-Tae Park; Sang-Ki Lee; Hayk H. Nersisyan; Yong-Soo Kim; Jong-Hyeon Lee

    2010-01-01

    An experimental study on the preparation of zirconium silicides was conducted using ZrSiO4–Mg, ZrSiO4–SiO2–Mg and ZrSiO4–ZrO2–Mg powder mixtures by the combustion synthesis (CS) technique. Test specimens having different composition ratios including Zr:Si=1:2, 1:1, 5:4, 5:3, 2:1, and 3:1 were employed in this study. Temperature profiles relative to all the starting compositions were measured using thermocouples, and the values of the

  17. Bulk Hydrides and Delayed Hydride Cracking in Zirconium Alloys

    NASA Astrophysics Data System (ADS)

    Tulk, Eric F.

    Zirconium alloys are susceptible to engineering problems associated with the uptake of hydrogen throughout their design lifetime in nuclear reactors. Understanding of hydrogen embrittlement associated with the precipitation of brittle hydride phases and a sub-critical crack growth mechanism known as Delayed Hydride Cracking (DHC) is required to provide the engineering justifications for safe reactor operation. The nature of bulk zirconium hydrides at low concentrations (< 100 wt. ppm) is subject to several contradictory descriptions in the literature associated with the stability and metastability of gamma-phase zirconium hydride. Due to the differing volume expansions (12-17%) and crystallography between gamma and delta hydride phases, it is suggested that the matrix yield strength may have an effect on the phase stability. The present work indicated that although yield strength can shift the phase stability, other factors such as microstructure and phase distribution can be as or more important. This suggests that small material differences are the reason for the literature discrepancies. DHC is characterised by the repeated precipitation, growth, fracture of brittle hydride phases and subsequent crack arrest in the ductile metal. DHC growth is associated primarily the ability of hydrogen to diffuse under a stress induced chemical potential towards a stress raiser. Knowledge of the factors controlling DHC are paramount in being able to appropriately describe DHC for engineering purposes. Most studies characterise DHC upon cooling to the test temperature. DHC upon heating has not been extensively studied and the mechanism by which it occurs is somewhat controversial in the literature. This work shows that previous thermo-mechanical processing of hydrided zirconium can have a significant effect on the dissolution behaviour of the bulk hydride upon heating. DHC tests with gamma-quenched, furnace cooled-delta and reoriented bulk hydrides upon heating and DHC upon cooling suggest that the amount of hydrogen in solution is the primary factor controlling the occurrence of DHC and consistent with the postulation that the stress induced chemical potential is the driving force for DHC.

  18. Synthetic environment technologies in STOW 97

    NASA Astrophysics Data System (ADS)

    Turner, Jeffrey T.; Koklauner, Karl

    1997-10-01

    The synthetic theater of war (STOW) is the major application of a Defense Advanced Research Projects Agency (DARPA) thrust in advanced distributed simulation (ADS). The STOW Program focuses on an advanced concept technology demonstration (ACTD) termed STOW 97 sponsored by DARPA with the United States Atlantic Command (USACOM). The successful implementation of STOW 97 technologies in November 1997 with the United Endeavor 98-1 exercise will mark the full operational capacity of the USACOM Joint Training, Analysis and Simulation Center. To support ADS applications up to the Joint Task Force level, STOW seeks to develop and demonstrate technologies enabling the integration of war-fighting through virtual and constructive simulations from geographically distributed locations in a common synthetic battlespace.

  19. Asia-Pacific Economic Cooperation (APEC) 97

    NSDL National Science Digital Library

    APEC 97 is the official site for the Asia-Pacific Economic Cooperation (APEC) Leaders and Ministers meeting held in Vancouver, Canada from November 21 to November 25, 1997. It provides a short history of APEC, short biographical notes on the leaders and ministers attending the meeting, in-depth information about the APEC economies, listings of venues and events, and a news section with up-to-date news of APEC 97. APEC is a grouping of 18 Asia-Pacific economies formed in 1989 to promote trade and cooperation in the region. Traditionally, the APEC meeting has focused on trade issues, but this year's focus was the economic crisis in Southeast Asia and South Korea.

  20. Vancouver Sun APEC 97 news archive

    NSDL National Science Digital Library

    The Vancouver Sun provides a comprehensive news archive of the issues and events at APEC 97, the APEC Leaders and Ministers meeting held in Vancouver, Canada from November 21 to November 25, 1997. APEC is a grouping of 18 Asia-Pacific economies formed in 1989 to promote trade and cooperation in the region. Traditionally, the APEC meeting has focused on trade issues, but this year's focus was the economic crisis in Southeast Asia and South Korea.

  1. Evaluation of the resistance of irradiated zirconium-liner cladding to iodine-induced stress corrosion cracking

    NASA Astrophysics Data System (ADS)

    Shimada, Sachio; Nagai, Masayuki

    1983-02-01

    An evaluation was made of irradiated zirconium-liner cladding for its resistance to iodine-induced stress corrosion cracking (SCC). Emphasis was put on irradiation-induced hardening in zirconium and SCC resistance in zirconium-liner cladding as compared with Zircaloy-2 cladding. The Vickers microhardness test revealed that crystal bar zirconium experienced less hardening than Zircaloy-2 during neutron exposure. The SCC resistance of zirconium-liner cladding was evaluated for failure strains under the tube pressurization SCC test, and compared with the results of Zircaloy-2 cladding. The failure strains of zirconium-liner cladding were significantly larger than those of Zircaloy-2 cladding over all neutron fluence ranges examined, e.g., more than ten times at 1.0 × 10 21n/ cm2 ( E > 1 MeV). Judging from our results on the Vickers microhardness and SCC tests, good SCC resistance of zirconium-liner cladding could be expected even at high fluences.

  2. Analysis of uranium-zirconium-carbon-oxygen quaternary system for applications in advanced zirconium carbide coated TRISO particles

    NASA Astrophysics Data System (ADS)

    Degange, Jonathan Lee

    The implementation of ZrC for use in oxide TRISO particles for Very High Temperature Reactor (VHTR) conditions to prevent kernel overpressurization and kernel migration has been proposed by several researchers. Analysis is performed incorporating first-principles thermodynamics along with out-of-pile experimental work. UO2+x-U4O9 powders are created and used for in-vacuo thermogravimetric testing with both carbon and zirconium carbide powders to evaluate the efficiency of ZrC for usage as an oxygen getter in oxide TRISO fuels.

  3. Nucleation and growth kinetics of zirconium-oxo-alkoxy nanoparticles.

    PubMed

    Labidi, Sana; Jia, Zixian; Amar, Mounir Ben; Chhor, Khay; Kanaev, Andrei

    2015-01-28

    Nucleation and growth of zirconium-oxo-alkoxy (ZOA) nanoparticles were studied in a sol-gel process in n-propanol solution at a hydrolysis ratio H between 1.0 and 2.7 and zirconium-n-propoxyde precursor concentrations between 0.10 and 0.15 mol l(-1). The chemical transformations were conducted in quasi-perfect micromixing conditions (Damköhler number Da ? 1) and the nanoparticle size evolution was monitored in situ with the light scattering method. The size of primary nanoparticles (nuclei) 2R0 = 3.6 nm was found to be almost independent of the preparation conditions. A remarkable similarity with the titanium-oxo-alkoxy (TOA) nanoparticles was observed. In particular, both systems show the induction stage of the sol-gel growth for a hydrolysis ratio H > 2.0 and stable oxometallate units for H? 2.0. However in contrast to TOA, no stable hierarchical ZOA units (clusters) with R0?R? 1.0 nm were observed, which makes this system less stable against aggregation, leading to polydispersed nanoparticles. PMID:25502510

  4. Hydrogen pickup measurements in zirconium alloys: Relation to oxidation kinetics

    NASA Astrophysics Data System (ADS)

    Couet, Adrien; Motta, Arthur T.; Comstock, Robert J.

    2014-08-01

    The optimization of zirconium-based alloys used for nuclear fuel cladding aims to reduce hydrogen pickup during operation, and the associated cladding degradation. The present study focuses on precisely and accurately measuring hydrogen pickup fraction for a set of alloys to specifically investigate the effects of alloying elements, microstructure and corrosion kinetics on hydrogen uptake. To measure hydrogen concentrations in zirconium alloys two techniques have been used: a destructive technique, Vacuum Hot Extraction, and a non-destructive one, Cold Neutron Prompt Gamma Activation Analysis. The results of both techniques show that hydrogen pickup fraction varies significantly with exposure time and between alloys. A possible interpretation of the results is that hydrogen pickup results from the need to balance charge. That is, the pickup of hydrogen shows an inverse relationship to oxidation kinetics, indicating that, if transport of charged species is rate limiting, oxide transport properties such as oxide electronic conductivity play a key role in the hydrogen pickup mechanism. Alloying elements (either in solid solution or in precipitates) would therefore impact the hydrogen pickup fraction by affecting charge transport.

  5. Zirconium speciation in lactate solutions and polyacrylate gels.

    PubMed

    Rose, J; Chauveteau, G; Tabary, R; Renard, M; Omari, A; Toulhoat, H

    2001-03-01

    Controlling gelation kinetics is an important objective for several applications (ceramic and thin film syntheses, reduction in permeability of porous rock, etc). There is a growing interest in studying the gelation of polymers by zirconium, a crosslinker of lower toxicity than the chromium which is still commonly used. XAS at the Zr K-edge was performed at the European Synchrotron Radiation Facility (ESRF) on the BM32 beamline. The fluorescence detection was used to carry out successful in situ speciation at concentrations as low as 36 ppm. The Zr speciation was determined both in ZrLa (where La stands for lactate) aqueous solutions and in gels of a terpolymer of acrylamide having 2% of zirconium reactive acrylate side groups and 2% of sulfonate groups introduced to prevent syneresis. XANES results show that Zr is always in a dodecahedral geometry. In ZrLa solutions. EXAFS results indicate that Zr species grow from a dimer Zr2(La)6 to a tetramer (Zr4(La)x) and then to larger polymers resulting from tetramer associations, as the Zr concentration decreases from 51840 ppm to 36ppm. In polymer gels, Zr species appear to be dimers at pH 6 while tetramers are found when gelation occurred at pH 7. Calculations taking into account multiple scattering effects as well as dynamic molecular calculation confirmed conclusions derived from conventional EXAFS analysis. PMID:11512896

  6. 34 CFR 97.116 - General requirements for informed consent.

    Code of Federal Regulations, 2013 CFR

    2013-07-01

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  7. 34 CFR 97.117 - Documentation of informed consent.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

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  8. 34 CFR 97.116 - General requirements for informed consent.

    Code of Federal Regulations, 2012 CFR

    2012-07-01

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  9. 34 CFR 97.116 - General requirements for informed consent.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

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  10. 34 CFR 97.117 - Documentation of informed consent.

    Code of Federal Regulations, 2013 CFR

    2013-07-01

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  11. 34 CFR 97.117 - Documentation of informed consent.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

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  12. 34 CFR 97.116 - General requirements for informed consent.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

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  13. 34 CFR 97.117 - Documentation of informed consent.

    Code of Federal Regulations, 2014 CFR

    2014-07-01

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  14. 34 CFR 97.116 - General requirements for informed consent.

    Code of Federal Regulations, 2014 CFR

    2014-07-01

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  15. 34 CFR 97.117 - Documentation of informed consent.

    Code of Federal Regulations, 2012 CFR

    2012-07-01

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  16. 7 CFR 97.144 - Additional marking or labeling.

    Code of Federal Regulations, 2012 CFR

    2012-01-01

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  17. 14 CFR Appendix - Special Federal Aviation Regulation No. 97

    Code of Federal Regulations, 2014 CFR

    2014-01-01

    ...CERTIFICATION AND OPERATIONS OPERATING REQUIREMENTS: DOMESTIC, FLAG, AND SUPPLEMENTAL OPERATIONS Special Federal Aviation Regulation No. 97 Editorial Note: For the text of SFAR No. 97, see part 91 of this...

  18. 46 CFR 97.37-11 - Carbon dioxide warning signs.

    Code of Federal Regulations, 2012 CFR

    2012-10-01

    ...2012-10-01 2012-10-01 false Carbon dioxide warning signs. 97.37-11...Emergency Equipment, Etc. § 97.37-11 Carbon dioxide warning signs. Each entrance to a space storing carbon dioxide cylinders, a space...

  19. 46 CFR 97.37-11 - Carbon dioxide warning signs.

    Code of Federal Regulations, 2013 CFR

    2013-10-01

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  20. 46 CFR 97.37-11 - Carbon dioxide warning signs.

    Code of Federal Regulations, 2014 CFR

    2014-10-01

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  1. 7 CFR 3201.97 - Sun care products.

    Code of Federal Regulations, 2014 CFR

    2014-01-01

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    Code of Federal Regulations, 2013 CFR

    2013-01-01

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  3. 30 CFR 18.97 - Inspection of machines; minimum requirements.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

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  4. 30 CFR 18.97 - Inspection of machines; minimum requirements.

    Code of Federal Regulations, 2012 CFR

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  5. 30 CFR 18.97 - Inspection of machines; minimum requirements.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

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  6. 47 CFR 97.211 - Space telecommand station.

    Code of Federal Regulations, 2012 CFR

    2012-10-01

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  7. 47 CFR 97.211 - Space telecommand station.

    Code of Federal Regulations, 2011 CFR

    2011-10-01

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  8. 47 CFR 97.211 - Space telecommand station.

    Code of Federal Regulations, 2013 CFR

    2013-10-01

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  9. 47 CFR 97.211 - Space telecommand station.

    Code of Federal Regulations, 2010 CFR

    2010-10-01

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  10. 40 CFR 97.357 - Closing of general accounts.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ...SO2 TRADING PROGRAMS CAIR NOX Ozone Season Allowance Tracking System § 97.357...and 97.361 for any CAIR NOX Ozone Season allowances in the account to one or more other CAIR NOX Ozone Season Allowance Tracking System...

  11. 40 CFR 97.357 - Closing of general accounts.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ...SO2 TRADING PROGRAMS CAIR NOX Ozone Season Allowance Tracking System § 97.357...and 97.361 for any CAIR NOX Ozone Season allowances in the account to one or more other CAIR NOX Ozone Season Allowance Tracking System...

  12. 7 CFR 97.400 - Extensions of time.

    Code of Federal Regulations, 2010 CFR

    2010-01-01

    ...2010-01-01 false Extensions of time. 97.400...Agriculture (Continued) AGRICULTURAL MARKETING SERVICE...Proceedings § 97.400 Extensions of time. Upon a showing of good cause, extensions of time not...

  13. 29 CFR 97.20 - Standards for financial management systems.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ...Standards for financial management systems. 97.20 Section 97...REQUIREMENTS FOR GRANTS AND COOPERATIVE AGREEMENTS TO STATE AND LOCAL...Standards for financial management systems. (a) A State must...The financial management systems of other grantees and...

  14. 33 CFR 401.97 - Closing procedures and ice navigation.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ...2011-07-01 false Closing procedures and ice navigation. 401.97 Section 401...Procedures § 401.97 Closing procedures and ice navigation. (a) No wintering vessel...the nearest Seaway station. (f) Where ice conditions restrict navigation,...

  15. 33 CFR 401.97 - Closing procedures and ice navigation.

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ...2014-07-01 false Closing procedures and ice navigation. 401.97 Section 401...Procedures § 401.97 Closing procedures and ice navigation. (a) No wintering vessel...the nearest Seaway station. (f) Where ice conditions restrict navigation,...

  16. 33 CFR 401.97 - Closing procedures and ice navigation.

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ...2013-07-01 false Closing procedures and ice navigation. 401.97 Section 401...Procedures § 401.97 Closing procedures and ice navigation. (a) No wintering vessel...the nearest Seaway station. (f) Where ice conditions restrict navigation,...

  17. 33 CFR 401.97 - Closing procedures and ice navigation.

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ...2012-07-01 false Closing procedures and ice navigation. 401.97 Section 401...Procedures § 401.97 Closing procedures and ice navigation. (a) No wintering vessel...the nearest Seaway station. (f) Where ice conditions restrict navigation,...

  18. A novel ultrasonication method in the preparation of zirconium impregnated cellulose for effective fluoride adsorption.

    PubMed

    Barathi, M; Kumar, A Santhana Krishna; Rajesh, N

    2014-05-01

    In the present work, we propose for the first time a novel ultrasound assisted methodology involving the impregnation of zirconium in a cellulose matrix. Fluoride from aqueous solution interacts with the cellulose hydroxyl groups and the cationic zirconium hydroxide. Ultrasonication ensures a green and quick alternative to the conventional time intensive method of preparation. The effectiveness of this process was confirmed by comprehensive characterization of zirconium impregnated cellulose (ZrIC) adsorbent using Fourier transform infrared spectroscopy (FT-IR), energy dispersive X-ray spectrometry (EDX) and X-ray diffraction (XRD) studies. The study of various adsorption isotherm models, kinetics and thermodynamics of the interaction validated the method. PMID:24394388

  19. Physicomechanical properties of the surface of a zirconium alloy modified by a pulsed ion beam

    NASA Astrophysics Data System (ADS)

    Chernov, I. P.; Berezneeva, E. V.; Beloglazova, P. A.; Ivanova, S. V.; Kireeva, I. V.; Lider, A. M.; Remnev, G. E.; Pushilina, N. S.; Cherdantsev, Yu. P.

    2014-04-01

    The physicomechanical properties of the surface of the Zr-1% Nb zirconium alloy modified by a pulsed carbon ion beam with a pulse duration of 80 ns, an energy of 200 keV, and a current density of 120 A/cm2 are studied at four regimes having different numbers of pulses. Irradiation by a carbon ion beam results in hardening of the surface layer to a depth of 2 ?m, grain refinement to 0.15-0.8 ?m, zirconium carbide formation, and a decrease in the hydrogen permeability of the zirconium alloy.

  20. Thermodynamic Analysis and Growth of Zirconium Carbide by Chemical Vapor Deposition

    NASA Astrophysics Data System (ADS)

    Wei, Sun; Hua, Hao Zheng; Xiang, Xiong

    Equilibrium calculations were used to optimize conditions for the chemical vapor deposition of zirconium carbide from zirconium halide + CxHy+H2+Ar system. The results show the CVD-ZrC phase diagram is divided into ZrC+C, ZrC and ZrC+Zr zones by C, Zr generating lines. For the same mole of ZrCl4 reactant, it needs higher concentration of CH4 to generate single ZrC phase than that of C3H6. Using these calculations as a guide, single-phase cubic zirconium carbide coatings were deposited onto graphite substrate.

  1. 47 CFR 97.309 - RTTY and data emission codes.

    Code of Federal Regulations, 2014 CFR

    2014-10-01

    ...2014-10-01 false RTTY and data emission codes. 97.309 Section 97.309 Telecommunication...Standards § 97.309 RTTY and data emission codes. (a) Where authorized by...emission using the following specified digital codes: (1) The 5-unit,...

  2. 40 CFR 97.384 - Opt-in process.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ...2011-07-01 2011-07-01 false Opt-in process. 97.384 Section 97.384 Protection...AIR PROGRAMS (CONTINUED) FEDERAL NOX BUDGET TRADING PROGRAM AND CAIR NOX AND SO2 TRADING...Opt-in Units § 97.384 Opt-in process. The permitting authority...

  3. 40 CFR 97.184 - Opt-in process.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ...2011-07-01 2011-07-01 false Opt-in process. 97.184 Section 97.184 Protection...AIR PROGRAMS (CONTINUED) FEDERAL NOX BUDGET TRADING PROGRAM AND CAIR NOX AND SO2 TRADING...Opt-In Units § 97.184 Opt-in process. The permitting authority...

  4. 40 CFR 97.84 - Opt-in process.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ...2010-07-01 false Opt-in process. 97.84 Section 97...CONTINUED) FEDERAL NOX BUDGET TRADING PROGRAM AND CAIR NOX...Opt-ins. § 97.84 Opt-in process. The permitting authority...issue or deny an initial NOX Budget opt-in permit for a...

  5. 40 CFR 97.84 - Opt-in process.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ...2011-07-01 false Opt-in process. 97.84 Section 97...CONTINUED) FEDERAL NOX BUDGET TRADING PROGRAM AND CAIR NOX...Opt-ins. § 97.84 Opt-in process. The permitting authority...issue or deny an initial NOX Budget opt-in permit for a...

  6. 40 CFR 97.184 - Opt-in process.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ...2010-07-01 2010-07-01 false Opt-in process. 97.184 Section 97.184 Protection...AIR PROGRAMS (CONTINUED) FEDERAL NOX BUDGET TRADING PROGRAM AND CAIR NOX AND SO2 TRADING...Opt-In Units § 97.184 Opt-in process. The permitting authority...

  7. 40 CFR 97.284 - Opt-in process.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ...2011-07-01 2011-07-01 false Opt-in process. 97.284 Section 97.284 Protection...AIR PROGRAMS (CONTINUED) FEDERAL NOX BUDGET TRADING PROGRAM AND CAIR NOX AND SO2 TRADING...Opt-in Units § 97.284 Opt-in process. The permitting authority...

  8. 47 CFR 97.513 - VE session manager requirements.

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ...2010-10-01 2010-10-01 false VE session manager requirements. 97.513 Section 97.513...Examination Systems § 97.513 VE session manager requirements. (a) A VE session manager may be selected by the VE team for each...

  9. 46 CFR 97.30-5 - Accidents to machinery.

    Code of Federal Regulations, 2011 CFR

    2011-10-01

    ...2011-10-01 false Accidents to machinery. 97.30-5 Section 97.30-5...Equipment § 97.30-5 Accidents to machinery. (a) In the event of an accident to a boiler, unfired pressure vessel, or machinery tending to render the further use of...

  10. 46 CFR 97.30-5 - Accidents to machinery.

    Code of Federal Regulations, 2012 CFR

    2012-10-01

    ...2012-10-01 false Accidents to machinery. 97.30-5 Section 97.30-5...Equipment § 97.30-5 Accidents to machinery. (a) In the event of an accident to a boiler, unfired pressure vessel, or machinery tending to render the further use of...

  11. 46 CFR 97.30-5 - Accidents to machinery.

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ...2010-10-01 false Accidents to machinery. 97.30-5 Section 97.30-5...Equipment § 97.30-5 Accidents to machinery. (a) In the event of an accident to a boiler, unfired pressure vessel, or machinery tending to render the further use of...

  12. 46 CFR 97.30-5 - Accidents to machinery.

    Code of Federal Regulations, 2013 CFR

    2013-10-01

    ...2013-10-01 false Accidents to machinery. 97.30-5 Section 97.30-5...Equipment § 97.30-5 Accidents to machinery. (a) In the event of an accident to a boiler, unfired pressure vessel, or machinery tending to render the further use of...

  13. 46 CFR 97.30-5 - Accidents to machinery.

    Code of Federal Regulations, 2014 CFR

    2014-10-01

    ...2014-10-01 false Accidents to machinery. 97.30-5 Section 97.30-5...Equipment § 97.30-5 Accidents to machinery. (a) In the event of an accident to a boiler, unfired pressure vessel, or machinery tending to render the further use of...

  14. 47 CFR 97.15 - Station antenna structures.

    Code of Federal Regulations, 2013 CFR

    2013-10-01

    ...2013-10-01 2013-10-01 false Station antenna structures. 97.15 Section 97.15 Telecommunication...General Provisions § 97.15 Station antenna structures. (a) Owners of certain antenna structures more than 60.96 meters (200...

  15. 47 CFR 97.15 - Station antenna structures.

    Code of Federal Regulations, 2011 CFR

    2011-10-01

    ...2011-10-01 2011-10-01 false Station antenna structures. 97.15 Section 97.15 Telecommunication...General Provisions § 97.15 Station antenna structures. (a) Owners of certain antenna structures more than 60.96 meters (200...

  16. 47 CFR 97.15 - Station antenna structures.

    Code of Federal Regulations, 2014 CFR

    2014-10-01

    ...2014-10-01 2014-10-01 false Station antenna structures. 97.15 Section 97.15 Telecommunication...General Provisions § 97.15 Station antenna structures. (a) Owners of certain antenna structures more than 60.96 meters (200...

  17. 47 CFR 97.15 - Station antenna structures.

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ...2010-10-01 2010-10-01 false Station antenna structures. 97.15 Section 97.15 Telecommunication...General Provisions § 97.15 Station antenna structures. (a) Owners of certain antenna structures more than 60.96 meters (200...

  18. 47 CFR 97.15 - Station antenna structures.

    Code of Federal Regulations, 2012 CFR

    2012-10-01

    ...2012-10-01 2012-10-01 false Station antenna structures. 97.15 Section 97.15 Telecommunication...General Provisions § 97.15 Station antenna structures. (a) Owners of certain antenna structures more than 60.96 meters (200...

  19. STS-97 Endeavour after RSS rollback

    NASA Technical Reports Server (NTRS)

    2000-01-01

    After rollback of the Rotating Service Structure (at left), Space Shuttle Endeavour stands ready for launch targeted for 10:06 p.m. EST tonight on mission STS-97 to the International Space Station. The orbiter carries the P6 Integrated Truss Segment containing solar arrays that will be temporarily installed to the Unity connecting module by the Z1 truss, recently delivered to and installed on the Station on mission STS-92. The two solar arrays are each more than 100 feet long. They will capture energy from the sun and convert it to power for the Station. Two spacewalks will be required to install the solar array connections.

  20. Functionalized Zirconium Phosphate Nano Platelets - From Surface Design to Drug Delivery

    E-print Network

    Mukherjee, Atashi

    2014-05-30

    the intended target or compartment. This dissertation will focus on the analytical characterization of zirconium phosphate (ZrP) in both alpha and theta phases as a drug delivery matrix utilizing multiple unique and novel analytical techniques. In the first...

  1. Zirconium Minerals from Mars, Moon and Earth Indicate Crustal 'Refugia' on Early Bombardment Surfaces

    NASA Astrophysics Data System (ADS)

    Moser, D. E.

    2015-02-01

    A comparison of the shock microstructural and U-Pb histories of zirconium minerals from the bombardment epoch of Mars, Moon and Earth points to perseverance of early planetary crustal domains throughout the large impactor flux.

  2. Methods for Investigating Gas Bubble Formation in Uranium-Zirconium Alloys

    E-print Network

    Mews, Kathryn Ann Wright

    2013-05-06

    Uranium-zirconium alloy nuclear fuels have many advantages as compared with ceramic fuels, especially for fast reactor systems. However, metallic fuels aren’t currently used in commercial power production due in part to issues with fuel swelling...

  3. 21 CFR 700.16 - Use of aerosol cosmetic products containing zirconium.

    Code of Federal Regulations, 2012 CFR

    2012-04-01

    ... 2012-04-01 false Use of aerosol cosmetic products containing zirconium. 700.16...HEALTH AND HUMAN SERVICES (CONTINUED) COSMETICS GENERAL Requirements for Specific Cosmetic Products § 700.16 Use of aerosol...

  4. 21 CFR 700.16 - Use of aerosol cosmetic products containing zirconium.

    Code of Federal Regulations, 2011 CFR

    2011-04-01

    ... 2010-04-01 true Use of aerosol cosmetic products containing zirconium. 700.16...HEALTH AND HUMAN SERVICES (CONTINUED) COSMETICS GENERAL Requirements for Specific Cosmetic Products § 700.16 Use of aerosol...

  5. 21 CFR 700.16 - Use of aerosol cosmetic products containing zirconium.

    Code of Federal Regulations, 2014 CFR

    2014-04-01

    ... 2014-04-01 false Use of aerosol cosmetic products containing zirconium. 700.16...HEALTH AND HUMAN SERVICES (CONTINUED) COSMETICS GENERAL Requirements for Specific Cosmetic Products § 700.16 Use of aerosol...

  6. 21 CFR 700.16 - Use of aerosol cosmetic products containing zirconium.

    Code of Federal Regulations, 2013 CFR

    2013-04-01

    ... 2013-04-01 false Use of aerosol cosmetic products containing zirconium. 700.16...HEALTH AND HUMAN SERVICES (CONTINUED) COSMETICS GENERAL Requirements for Specific Cosmetic Products § 700.16 Use of aerosol...

  7. Synthesis and catalytic activity of titanium and zirconium chiral diolate complexes

    SciTech Connect

    Grumbine, S.K.; Clark, D.L.; Scott, B.; Watkin, J.G. [Los Alamos National Laboratory, NM (United States)

    1996-10-01

    New mono-cyclopentadienyl complexes of titanium and zirconium which contain a chiral diolate have been synthesized. Catalytic enantioselective C-C bond forming reactions will be discussed along with the structural characteristics of the catalyst precursors.

  8. Electrochemical protection of zirconium in oxidizing hydrochloric acid solutions

    SciTech Connect

    Yuu, T-L.; Maguire, M.

    1984-06-01

    An electrochemical protection technique using cathodic polarization to maintain zirconium below its critical repassivation potential was used to avoid pitting and stress corrosion cracking (SCC) in hydrochloric acid (HCI) containing ferric ions (Fe/sup +3/). Corrosion and pit penetration rates are reported for pickled, abraded, and as-received surface conditions in 10, 20, and 37% HCI containing 50, 100, or 500 ppm Fe/sup +3/ at temperatures to boiling. The pickled surface was the least susceptible to pitting in the 64 day tests. Electrochemical protection is then evaluated for total immersion, partial immersion, U-bend, and constant strain rate tensile tests. Protection is effective in eliminating pitting and SCC in 10 and 20% HCI containing Fe/sup +3/.

  9. On the oxidation of Zirconium by heat tinting

    NASA Astrophysics Data System (ADS)

    El-Shanshoury, I. A.; Chirkin, A. V.; El-Yazgi, A.

    1987-06-01

    The early stages of the oxidation of iodide zirconium in the temperature range 673-823 K were studied using the heat tinting technique. An activation energy of 128 kJ/mol was calculated. Anisotropy of the oxidation is significant and depends on the preferred orientation of the grains. Twins have indicated the anisotropic nature of the oxidation process by showing different color contrasts. It was found that the increase in the thickness of the oxide film takes place by the nucleation and growth mechanism. This process was noted to be extremely dependent on the orientation of the grains. Preferential oxidation of the bulk of the grains was observed and substructure formation could be easily identified.

  10. Fabrication of NiO/zirconium oxide nanofibers by electrospinning.

    PubMed

    Sundarrajan, Subramanian; Venkatesan, Arunachalam; Agarwal, Satya R; Ahamed, Nabeela Nasreen Shaik Anwar; Ramakrishna, Seeram

    2014-12-01

    The electrospinning technique has been used to fabricate 1D inorganic-organic composite nanofibers from solutions containing poly(vinyl alcohol) (PVA) and suitable aqueous precursors of nickel and zirconium ions. Upon calcination, nickel oxide/zirconia nanofibers retained the original morphological features of as-spun nanofibers. X-ray diffraction was used to identify the crystalline nature of the final product and analytical tools such as Fourier transform infrared (FTIR) spectroscopy, scanning electron microscopy (SEM), transmission electron microscopy (TEM) and atomic force microscopy (AFM) were employed to elucidate the pathway of ceramic phase formation and the systematic evolution of morphological features in the as-spun and calcined fibers. These fibers will find potential applications in biomedical field. PMID:25491841

  11. Titanium-Zirconium-Nickel Alloy Inside Marshall's Electrostatic Levitator (ESL)

    NASA Technical Reports Server (NTRS)

    2003-01-01

    This Photo, which appeared on the July cover of `Physics Today', is of the Electrostatic Levitator (ESL) at NASA's Marshall Space Flight Center (MSFC). The ESL uses static electricity to suspend an object (about 3-4 mm in diameter) inside a vacuum chamber allowing scientists to record a wide range of physical properties without the sample contracting the container or any instruments, conditions that would alter the readings. Once inside the chamber, a laser heats the sample until it melts. The laser is then turned off and the sample cools, changing from a liquid drop to a solid sphere. In this particular shot, the ESL contains a solid metal sample of titanium-zirconium-nickel alloy. Since 1977, the ESL has been used at MSFC to study the characteristics of new metals, ceramics, and glass compounds. Materials created as a result of these tests include new optical materials, special metallic glasses, and spacecraft components.

  12. Titanium-Zirconium-Nickel Alloy Inside Marshall's Electrostatic Levitator (ESL)

    NASA Technical Reports Server (NTRS)

    2003-01-01

    This is a close-up of a sample of titanium-zirconium-nickel alloy inside the Electrostatic Levitator (ESL) vacuum chamber at NASA's Marshall Space Flight Center (MSFC). The ESL uses static electricity to suspend an object (about 3-4 mm in diameter) inside a vacuum chamber allowing scientists to record a wide range of physical properties without the sample contracting the container or any instruments, conditions that would alter the readings. Once inside the chamber, a laser heats the sample until it melts. The laser is then turned off and the sample cools, changing from a liquid drop to a solid sphere. Since 1977, the ESL has been used at MSFC to study the characteristics of new metals, ceramics, and glass compounds. Materials created as a result of these tests include new optical materials, special metallic glasses, and spacecraft components.

  13. Effect of yttrium on nucleation and growth of zirconium hydrides

    NASA Astrophysics Data System (ADS)

    Li, Changji; Xiong, Liangyin; Wu, Erdong; Liu, Shi

    2015-02-01

    Addition of yttrium in zirconium causes precipitates of yttrium, which form two types of particles and are oxidized upon heat treatment. One type of particles with sub-micrometer scale sizes has a low population, whereas the other with nano scale sizes has a high population and cluster distribution. Owing to strong affinity of yttrium to hydrogen, the nanoparticles, mostly within the grains of the Zr-Y alloy, attract nucleation of hydrides at the clusters of the nanoparticles and cause preferential distribution of intragranular hydrides. In comparison with that of Zr, additional nanoparticles in the Zr-Y alloy impede further growth of hydride precipitates during hydriding. It is deduced that the impediment of growing hydride precipitates by the nanoparticles is developed during an auto-catalytic nucleation process, which leads to formation of thin and intragranular hydrides, favorable to mitigation of hydride embrittlement.

  14. The Indigenous World, 1996-97 = El Mundo Indigena, 1996-97.

    ERIC Educational Resources Information Center

    Erni, Christian, Ed.

    This annual publication (published separately in English and Spanish) examines political, legal, social, and educational issues concerning indigenous peoples around the world during 1996-97. Part I highlights news events and ongoing situations in specific countries. In North America, these include threats of proposed oil drilling on sacred sites…

  15. Fabrication and characterization of zirconium carbide (ZrC) nanofibers with thermal storage property

    Microsoft Academic Search

    Young Sik Nam; Xue Mei Cui; Lim Jeong; Jae Yeol Lee; Won Ho Park

    2009-01-01

    Zirconium carbide (ZrC) nanofibers were fabricated by the electrospinning method and subsequent heat-treatment. The solution for electrospinning was prepared by dissolving zirconium acetyl acetonate and cellulose acetate in glacial acetic acid and 2,4-pentanedione as common solvents. The effects of the solution properties used for electrospinning, including the concentrations of the starting materials, the C\\/Zr ratio of the solutions, and soaking

  16. Fabrication of zirconium carbide (ZrC) ultra-thin fibers by electrospinning

    Microsoft Academic Search

    Xue Mei Cui; Young Sik Nam; Jae Yeol Lee; Won Ho Park

    2008-01-01

    Zirconium carbide (ZrC) nanofibers were successfully fabricated by electrospinning and annealing. The electrospinning solution was prepared by dissolving zirconium acetyl acetonate, phenolic resins in a solvent mixture of ethyl alcohol and 2,4-pentanedione. Electrospinning was carried out successfully at a positive voltage of 26 kV, with a mass flow rate of 1.0 mL\\/h, and a working distance of 10 cm. The ZrC phase was

  17. Co-Rolled U10Mo/Zirconium-Barrier-Layer Monolithic Fuel Foil Fabrication Process

    SciTech Connect

    G. A. Moore; M. C. Marshall

    2010-01-01

    Integral to the current UMo fuel foil processing scheme being developed at Idaho National Laboratory (INL) is the incorporation of a zirconium barrier layer for the purpose of controlling UMo-Al interdiffusion at the fuel-meat/cladding interface. A hot “co-rolling” process is employed to establish a ~25-µm-thick zirconium barrier layer on each face of the ~0.3-mm-thick U10Mo fuel foil.

  18. A simple route for organic covalent grafting onto zirconium carbide particles

    NASA Astrophysics Data System (ADS)

    Lucas, Romain; Pizon, David; Laborde, Etienne; Trolliard, Gilles; Foucaud, Sylvie; Maître, Alexandre

    2013-12-01

    Starting from core-shell zirconium carbide powders, a covalent grafting was described, using a direct nucleophilic substitution in diethyl ether. Thus, two different organic molecules were attached onto the surface of the ceramic, through Sisbnd Osbnd Zr and Csbnd Osbnd Zr bonds. The materials were characterized by means of TEM and XPS characterizations. These new systems could represent an original route to elaborate zirconium carbide-based hybrid materials.

  19. Synthesis and characterization of novel aramid-zirconium oxide micro-composites

    Microsoft Academic Search

    H. U. Rehman; M. I. Sarwar; Z. Ahmad; H. Krug; H. Schmidt

    1997-01-01

    New micro-composites containing different proportions of zirconium oxide in aromatic polyamide have been prepared via a sol-gel process. Poly(phenyleneterephthalamide) chains with carbonyl chloride end groups were synthesized by reacting a mixture of p- and m-phenylene diamines with terephthaloyl chloride. The chain ends were endcapped with aminophenyltrimethoxysilane. Appropriate amount of zirconium propoxide solution (82.3 wt.%) in propanol was mixed in the

  20. X-Ray Diffraction Study of Shock-Induced Phase Transformations in Zirconium and Bismuth

    Microsoft Academic Search

    A. M. Podurets; V. V. Dorokhin; R. F. Trunin

    2003-01-01

    Pulse X-ray patterns of polycrystalline zirconium and monocrystalline bismuth are obtained at the moment of shock-wave stimulation of samples. The exposure time of X-ray photography is 0.2–0.3 ms. Zirconium samples are investigated at shock pressures of 5, 9.5, 15, and 29 GPa. At P = 5 and 9.5 GPa, the structure of the initial a-phase is observed. At 15 and

  1. Zirconium Copper — a New Material for Use at Low Temperatures?

    NASA Astrophysics Data System (ADS)

    Woodcraft, Adam L.

    2006-09-01

    Cryogenic instruments usually require components with high thermal conductivity. Pure (non alloyed) copper offers very high conductivity, but is soft and not thus always suitable structurally. High conductivity beryllium copper (BeCu) alloys are a common choice when copper is unsuitable since they offer a good compromise between hardness and thermal conductivity. These alloys contain a small (<1%) amount of beryllium (along with a few percent of nickel or cobalt), with strength being obtained by precipitation hardening. An alternative precipitation hardened copper alloy is C15000 zirconium copper (ZrCu), which contains < 0.2% zirconium with the remainder being copper. This material does not seem to be generally used in cryogenic systems, though hardness and strength are comparable to BeCu. Moreover, the lower impurity content suggests that the thermal conductivity should be higher than for BeCu. I present residual resistivity measurements suggesting that ZrCu does indeed possess considerably higher conductivity than BeCu (19 Wm-1K-1 at 1 K compared to approximately 2 Wm-1K-1), and should therefore be a very useful material. A method is given for extrapolating the low temperature thermal conductivity values to temperatures up to 300 K; good agreement is seen with room temperature data-sheet values. This extrapolation method is shown to also be applicable to BeCu and thus presumably other dilute copper alloys, and is used to give recommended values for coin silver and various BeCu alloy types, including C17510 and C17200.

  2. Zirconium Copper - a New Material for Use at Low Temperatures?

    SciTech Connect

    Woodcraft, Adam L. [School of Physics and Astronomy, Cardiff University, Cardiff, 5 The Parade, Cardiff, CF24 3YB (United Kingdom)

    2006-09-07

    Cryogenic instruments usually require components with high thermal conductivity. Pure (non alloyed) copper offers very high conductivity, but is soft and not thus always suitable structurally. High conductivity beryllium copper (BeCu) alloys are a common choice when copper is unsuitable since they offer a good compromise between hardness and thermal conductivity. These alloys contain a small (<1%) amount of beryllium (along with a few percent of nickel or cobalt), with strength being obtained by precipitation hardening. An alternative precipitation hardened copper alloy is C15000 zirconium copper (ZrCu), which contains < 0.2% zirconium with the remainder being copper. This material does not seem to be generally used in cryogenic systems, though hardness and strength are comparable to BeCu. Moreover, the lower impurity content suggests that the thermal conductivity should be higher than for BeCu. I present residual resistivity measurements suggesting that ZrCu does indeed possess considerably higher conductivity than BeCu (19 Wm-1K-1 at 1 K compared to approximately 2 Wm-1K-1), and should therefore be a very useful material. A method is given for extrapolating the low temperature thermal conductivity values to temperatures up to 300 K; good agreement is seen with room temperature data-sheet values. This extrapolation method is shown to also be applicable to BeCu and thus presumably other dilute copper alloys, and is used to give recommended values for coin silver and various BeCu alloy types, including C17510 and C17200.

  3. Ion beam mixing of chromium or zirconium films with sapphire

    SciTech Connect

    McHargue, C.J. [Tennessee Univ., Knoxville, TN (United States); Joslin, D.L.; White, C.W. [Oak Ridge National Lab., TN (United States); daSilva, M.F.; Alves, E. [National Inst. for Industrial Technology and Engineering, Sacavem (Portugal); Soares, J.C. [Lisbon Univ. (Portugal)

    1995-12-31

    Ion beam mixing of thin metallic films deposited on sapphire substrates was studied for chromium or zirconium films deposited on single crystalline {alpha}-Al{sub 2}0{sub 3} substrates. Evidence for the influence of equilibrium thermodynamic factors was sought by comparing the effects of bombarding with oxygen ions (300 and 1073 K) with those of neon ions (300 K). Thermodynamic calculations indicate that mixing might occur for Zr/sapphire at 1073 K but not at 300 K. Chromium/sapphire should not be mixed at either temperature. The implantation energy placed the peak oxygen concentration at the metal/sapphire interface in an attempt to maintain an equilibrium ratio of cations/anions and promote a radiation-induced chemical reaction across the interface. Rutherford backscattering-ion channeling measurements indicated that the widths of ``mixed`` regions were consistent with those predicted from ballistic considerations. Other experiments employed a heavier ion (krypton) as the mixing ion (300 K) in order to increase the mixing efficiency. Rutherford backscattering-ion channeling and x-ray photoelectron spectroscopy were used to determine the extent and nature of any interface modification. XPS results indicated that only metallic chromium (Cr{sup 0}) was present near the interface before and after irradiation with Kr at 300 K. Zirconium exhibited only the metallic state (Zr{sup 0}) in the as-deposited film but was present as both Zr{sup 0} and Zr{sup 4{plus}} after irradiation. Some metallic aluminum (AI{sup O}) was detected near the Zr/sapphire interface, suggesting that a local chemical reaction between Zr and the sapphire occurred during bombardment. No long-range material transport was detected for any experimental condition examined; the width of the ``mixed` region in each case was consistent with that expected for ballistic effects.

  4. Graded selective coatings based on zirconium and titanium oxynitride

    NASA Astrophysics Data System (ADS)

    Rizzo, A.; Signore, M. A.; Tapfer, L.; Piscopiello, E.; Cappello, A.; Bemporad, E.; Sebastiani, M.

    2009-06-01

    The aim of this study was the development and characterization of transition metal oxynitride multilayers for optical applications. The reactive RF magnetron sputtering technique in rotation mode was used for stacking of zirconium oxynitride (ZrNO) and titanium oxynitride (TiNO) nanolayers. The depositions were carried out in a reactive Ar+N2+O2 atmosphere by sputtering titanium and zirconium targets. By means of different substrate rotation speeds, the bilayer period has been changed in the range 11-20 nm. A multilayer deposition rate increasing with the bilayer period decreasing has been evaluated. Structural, compositional, mechanical and optical analyses have been performed. The x-ray diffraction spectra confirmed the formation of a multilayer structure with a nitride formation prevalence. Non-abrupt interfaces between the layers and non-uniform chemical composition (chemical intermixing) have been detected by transmission electron microscope (TEM) observations. The gradient interface structure turns out to be an advantage for the improvement of the mechanical properties. Higher hardness values were calculated by the Chicot-Lesage and Jonsson-Hogmark models for TiNO/ZrNO multilayer compared with monolayer TiNO and ZrNO coatings. Also SIMS analysis has confirmed a compositional interface grading but also an increase in oxygen content with decreasing substrate rotation speed or similarly with decreasing deposition rate. Moreover, a tuning of the optical properties, going from metallic behaviour to dielectric with the decrease in the substrate rotation speed has been gained. The variation of the deposition rate allows a sort of 'regulation' of the oxygen incorporation with a precise tailoring of the optical properties. This result can be employed with the aim of depositing graded composition multilayer systems with a precise control of their optical selective wavelength properties. The improvement in the mechanical performance in graded oxynitride multilayer coatings would also allow an increase in the optical device lifetime.

  5. The impact of zirconium oxide radiopacifier on the early hydration behaviour of white Portland cement.

    PubMed

    Coleman, Nichola J; Li, Qiu

    2013-01-01

    Zirconium oxide has been identified as a candidate radiopacifying agent for use in Portland cement-based biomaterials. During this study, the impact of 20 wt.% zirconium oxide on the hydration and setting reactions of white Portland cement (WPC) was monitored by powder X-ray diffraction (XRD), (29)Si and (27)Al magic angle spinning nuclear magnetic resonance spectroscopy (MAS NMR), transmission electron microscopy (TEM) and Vicat apparatus. The presence of 20 wt.% zirconium oxide particles in the size-range of 0.2 to 5 ?m was found to reduce the initial and final setting times of WPC from 172 to 147 min and 213 to 191 min, respectively. Zirconium oxide did not formally participate in the chemical reactions of the hydrating cement; however, the surface of the zirconium oxide particles presented heterogeneous nucleation sites for the precipitation and growth of the early C-S-H gel products which accelerated the initial setting reactions. The presence of zirconium oxide was found to have little impact on the development of the calcium (sulpho)aluminate hydrate phases. PMID:25428091

  6. STS-97 Endeavour after RSS rollback

    NASA Technical Reports Server (NTRS)

    2000-01-01

    Against a cloudless blue sky, Space Shuttle Endeavour stands ready for launch after the rollback of the Rotating Service Structure, at left. Endeavour is targeted for launch tonight at about 10:06 p.m. EST on mission STS-97 to the International Space Station. The orbiter carries the P6 Integrated Truss Segment containing solar arrays that will be temporarily installed to the Unity connecting module by the Z1 truss, recently delivered to and installed on the Station on mission STS-92. The two solar arrays are each more than 100 feet long. They will capture energy from the sun and convert it to power for the Station. Two spacewalks will be required to install the solar array connections.

  7. STS-97 Endeavour after RSS rollback

    NASA Technical Reports Server (NTRS)

    2000-01-01

    As dawn breaks on the horizon, Space Shuttle Endeavour is seen standing ready for launch, targeted for 10:06 p.m. EST tonight on mission STS-97 to the International Space Station. The Rotating Service Structure was rolled back just before dawn. On top of the orange external tank is the Gaseous Oxygen Vent Arm and its vent hood, known as the '''beanie cap.''' The hood is raised to clear the external tank 2.5 minutes before launch. The orbiter carries the P6 Integrated Truss Segment containing solar arrays that will be temporarily installed to the Unity connecting module by the Z1 truss, recently delivered to and installed on the Station on mission STS-92. The two solar arrays are each more than 100 feet long. They will capture energy from the sun and convert it to power for the Station. Two spacewalks will be required to install the solar array connections.

  8. Preparation and characterization of three-dimensional carbon fiber reinforced zirconium carbide composite by precursor infiltration and pyrolysis process

    Microsoft Academic Search

    Dan Zhao; Changrui Zhang; Haifeng Hu; Yudi Zhang

    2011-01-01

    Three-dimensional carbon fiber reinforced zirconium carbide composite (3D C\\/ZrC) was fabricated for ultra high temperature applications by precursor infiltration and pyrolysis (PIP) process using the mixture of zirconium butoxide (Zr(OC4H9)4) and divinylbenzene (DVB) as precursor of zirconium carbide. The micro-structural, mechanical and ablative properties of the 3D C\\/ZrC composite were studied. The flexural strength of the composite was 107.6MPa, the

  9. Preparation of zirconium oxy ion-imprinted particle for the selective separation of trace zirconium ion from water.

    PubMed

    Ren, Yueming; Liu, Pingxin; Liu, Xiaoli; Feng, Jing; Fan, Zhuangjun; Luan, Tianzhu

    2014-10-01

    Zr(IV) oxy ion-imprinted particle (Zr-IIP) was prepared using the metal ion imprinting technique in a sol-gel process on the surface of amino-silica. The dosages of zirconium ions as imprinted target, (3-aminopropyl) triethoxysilane (APTES) as a functional monomer and teraethyl orthosilicate (TEOS) as a cross-linker were optimized. The prepared Zr-IIP and Zr(IV) oxy ion non-imprinted particle (Zr-NIP) were characterized. pH effect, binding ability and the selectivity were investigated in detail. The results showed that the Zr-IIP had an excellent binding capacity and selectivity in the water. The equilibrium data fitted well to the pseudo-second-order kinetic and the Langmuir model for Zr(IV) binding onto Zr-IIP, respectively. The saturate binding capacity of Zr-IIP was found to be 196.08 ?mol g(-1), which was 18 times higher than that of Zr-NIP. The sequence of binding efficiency of Zr-IIP for various ions was Zr(IV)>Cu(II)>Sb(III)>Eu(III). The coordination number has an important effect on the dimensional binding capacity. The equilibrium binding capacity of Zr-IIP for Zr(IV) decreased little under various concentrations of Pb(II) ions. The analysis of relative selectivity coefficient (Kr) indicated that the Zr-IIP had an appreciable binding specificity towards Zr(IV) although the competitive ions coexisted in the water. The Zr-IIP could serve as an efficient selective material for recovering or removing zirconium from the water environment. PMID:25004058

  10. ID Name Start Finish 1 1997 Construction 02.01.97 05.01.98

    E-print Network

    and purchasing of heat exchangers 21.04.97 26.09.97 47 Install heat exchangers 16.10.97 26.11.97 48 Install gas.01.97 05.01.98 20 Install gas tubes in hall West 26.01.97 26.02.97 21 Install gas tubes from hall West stations 02.01.97 18.06.97 24 Safety discussion about gas hut 01.08.97 25.09.97 25 Design model gas system

  11. Highly enantioselective zirconium-catalyzed cyclization of aminoalkenes.

    PubMed

    Manna, Kuntal; Everett, William C; Schoendorff, George; Ellern, Arkady; Windus, Theresa L; Sadow, Aaron D

    2013-05-15

    Aminoalkenes are catalytically cyclized in the presence of cyclopentadienylbis(oxazolinyl)borato group 4 complexes {PhB(C5H4)(Ox(R))2}M(NMe2)2 (M = Ti, Zr, Hf; Ox(R) = 4,4-dimethyl-2-oxazoline, 4S-isopropyl-5,5-dimethyl-2-oxazoline, 4S-tert-butyl-2-oxazoline) at room temperature and below, affording five-, six-, and seven-membered N-heterocyclic amines with enantiomeric excesses of >90% in many cases and up to 99%. Mechanistic investigations of this highly selective system employed synthetic tests, kinetics, and stereochemistry. Secondary aminopentene cyclizations require a primary amine (1-2 equiv vs catalyst). Aminoalkenes are unchanged in the presence of a zirconium monoamido complex {PhB(C5H4)(Ox(4S-iPr,Me2))2}Zr(NMe2)Cl or a cyclopentadienylmono(oxazolinyl)borato zirconium diamide {Ph2B(C5H4)(Ox(4S-iPr,Me2))}Zr(NMe2)2. Plots of initial rate versus [substrate] show a rate dependence that evolves from first-order at low concentration to zero-order at high concentration, and this is consistent with a reversible substrate-catalyst interaction preceding an irreversible step. Primary kinetic isotope effects from substrate conversion measurements (k'obs((H))/k'obs((D)) = 3.3 ± 0.3) and from initial rate analysis (k2((H))/k2((D)) = 2.3 ± 0.4) indicate that a N-H bond is broken in the turnover-limiting and irreversible step of the catalytic cycle. Asymmetric hydroamination/cyclization of N-deutero-aminoalkenes provides products with higher optical purities than obtained with N-proteo-aminoalkenes. Transition state theory, applied to the rate constant k2 that characterizes the irreversible step, provides activation parameters consistent with a highly organized transition state (?S(++) = -43(7) cal·mol(-1) K(-1)) and a remarkably low enthalpic barrier (?H(++) = 6.7(2) kcal·mol(-1)). A six-centered, concerted transition state for C-N and C-H bond formation and N-H bond cleavage involving two amidoalkene ligands is proposed as most consistent with the current data. PMID:23631736

  12. Synthesis and liquid crystal phase transitions of zirconium phosphate disks

    NASA Astrophysics Data System (ADS)

    Shuai, Min

    Solvent-mediated self-assembly of nanoparticles is an effective and efficient way for the bottom-up organization of functional structures. The primary object of this work is to build up a model system for the study of suspensions of disk-shaped nanoparticles, and use it for the study of self-assembly and discotic liquid crystal phase transitions of discotic particles. The work was introduced by the control over the size and polydispersity of zirconium phosphate (ZrP) disks through synthesis. Systematic experiments revealed that regular-shaped alpha-zirconium phosphate crystalline disks with a size-to-thickness ratio from 1 to 50 and size polydispersity as low as 0.2 can be obtained through hydrothermal treatment in 3 M to 15 M phosphoric acid solutions. Transmission and scanning electron micrographs revealed that the growth of the disks is mediated by oriented attachment, which happened continuously throughout the hydrothermal treatment between various sized disks. Ostwald ripening is effective in improving the regularity of the shape of the disks, especially under prolonged hydrothermal treatment. Under the microwave assisted hydrothermal conditions, the rate of attachment on the flat surfaces of the disks is accelerated, which leads to the formation of the column-shaped crystals. With the ability to adjust the size, aspect ratio, and polydispersity of ZrP disks, the study on self-assembly behavior and the discotic liquid crystal phases was enabled. Firstly, liquid crystal phases of aqueous suspensions of ZrP disks were investigated. Iridescent smectic phase and the critical points of phase transitions were found. Moreover, monolayer ZrP nanosheets with extremely high aspect ratio, which were achieved by exfoliating the ZrP crystals, were also used in this study. The high aspect ratio of nanosheets produces a laminar phase at low nanosheet concentration. Chiral liquid crystal phases were demonstrated when increased the concentration of the nanosheets. The competition between the chirality and layering leads to twisted and layered structures. For the final part, solvent-mediated self-assembly of disks and nanosheets via undulation of liquid crystal phases showed an interesting approach for bottom-up design of functional nano-structures.

  13. Preparation, characterization and adsorption behavior of tannin-modified poly(glycidylmethacrylate)-grafted zirconium oxide-densified cellulose for the selective separation of bovine serum albumin.

    PubMed

    Anirudhan, Thayyath Sreenivasan; Rejeena, Sylaja Raveendran; Tharun, Abdul Rauf

    2012-05-01

    Bovine serum albumin (BSA) is one of the major constituents of blood plasma and its recovery is a significantly useful subject for biomedical applications. In this study, a novel adsorbent, tannin-modified poly(glycidylmethacrylate)-grafted zirconium oxide-densified cellulose (TMPGZDC) was synthesized by graft copolymerization reaction of glycidylmethacrylate onto zirconium oxide-densified cellulose (ZDC) in the presence of N,N'-methylenebisacrylamide as cross-linker followed by tannin immobilization. The adsorbent was characterized using TG, XRD, SEM/EDS, FTIR and fluorescence analyses. The efficiency of the TMPGZDC to adsorb BSA from aqueous solutions was studied at different optimized conditions. The optimum pH for maximum adsorption was found to be 4.8 with the adsorption percentage of 97.8% for an initial concentration of 100 mg/L. Equilibrium was achieved within 30 min. The kinetic data were found to follow pseudo-first-order model which is based on solid capacity. The well agreement of equilibrium data with Langmuir isotherm and Redlich-Peterson isotherm models confirms the monolayer coverage of BSA onto TMPGZDC surface and the maximum adsorption capacity at 30°C was found to be 93.11 mg/g. Thermodynamic study revealed an exothermic adsorption process. TMPGZDC was found to be efficient in the selective adsorption of proteins. Spent adsorbent was effectively regenerated [correction of degenerated] with 0.1 M NaCl. The present investigation shows that TMPGZDC is a promising adsorbent for the recovery of BSA from aqueous solutions and protein mixtures. PMID:22230358

  14. Zirconium phosphate waste forms for low-temperature stabilization of cesium-137-containing waste streams

    SciTech Connect

    Singh, D.; Wagh, A.S.; Tlustochowicz

    1996-04-01

    Novel chemically bonded phosphate ceramics are being developed and fabricated for low-temperature stabilization and solidification of waste streams that are not amenable to conventional high-temperature stabilization processes because volatiles are present in the wastes. A composite of zirconium-magnesium phosphate has been developed and shown to stabilize ash waste contaminated with a radioactive surrogate of {sup 137}Cs. Excellent retainment of cesium in the phosphate matrix system was observed in Toxicity Characteristic Leaching Procedure tests. This was attributed to the capture of cesium in the layered zirconium phosphate structure by intercalation ion-exchange reaction. But because zirconium phosphate has low strength, a novel zirconium/magnesium phosphate composite waste form system was developed. The performance of these final waste forms, as indicated by compression strength and durability in aqueous environments, satisfy the regulatory criteria. Test results indicate that zirconium-magnesium-phosphate-based final waste forms present a viable technology for treatment and solidification of cesium-contaminated wastes.

  15. Zirconium-based alloys, nuclear fuel rods and nuclear reactors including such alloys, and related methods

    DOEpatents

    Mariani, Robert Dominick

    2014-09-09

    Zirconium-based metal alloy compositions comprise zirconium, a first additive in which the permeability of hydrogen decreases with increasing temperatures at least over a temperature range extending from 350.degree. C. to 750.degree. C., and a second additive having a solubility in zirconium over the temperature range extending from 350.degree. C. to 750.degree. C. At least one of a solubility of the first additive in the second additive over the temperature range extending from 350.degree. C. to 750.degree. C. and a solubility of the second additive in the first additive over the temperature range extending from 350.degree. C. to 750.degree. C. is higher than the solubility of the second additive in zirconium over the temperature range extending from 350.degree. C. to 750.degree. C. Nuclear fuel rods include a cladding material comprising such metal alloy compositions, and nuclear reactors include such fuel rods. Methods are used to fabricate such zirconium-based metal alloy compositions.

  16. The Genes Coding for Enterocin EJ97 Production by Enterococcus faecalis EJ97 Are Located on a Conjugative Plasmid

    PubMed Central

    Sánchez-Hidalgo, Marina; Maqueda, Mercedes; Gálvez, Antonio; Abriouel, Hikmate; Valdivia, Eva; Martínez-Bueno, Manuel

    2003-01-01

    Enterococcus faecalis EJ97 produces a cationic bacteriocin (enterocin EJ97) of low molecular mass (5,327.7 Da). The complete amino acid sequence of enterocin EJ97 was elucidated after automated microsequencing of oligopeptides generated by endoproteinase GluC digestion and cyanogen bromide treatment. Transfer of the 60-kb conjugative plasmid pEJ97 from the bacteriocinogenic strain E. faecalis EJ97 to E. faecalis OG1X conferred bacteriocin production and resistance on the recipient. The genetic determinants of enterocin EJ97 were located in an 11.3-kb EcoRI-BglII DNA fragment of pEJ97. This region was cloned and sequenced. It contains the ej97A structural gene plus three open reading frames (ORFs) (ej97B, ej97C, and ej97D) and three putative ORFs transcribed in the opposite direction (orfA, orfB, and orfC). The gene ej97A translated as a 44-amino-acid residue mature protein lacking a leader peptide with no homology to other bacteriocins described so far. The product of ej97B (Ej97B) shows strong homology in its C-terminal domain to the superfamily of bacterial ATP-binding cassette transporters. The products of ej97C (Ej97C) and ej97D (Ej97D) could be proteins with 71 and 64 residues, respectively, of unknown functions and with no significant similarity to known proteins. There are two additional ORFs (ORF1 and ORF6) flanking the ej97 module, which have been identified as a transposon-like structure (tnp). ORF1 shows similarities to transposase of the Lactococcus lactis element ISS1 and is up to 50% identical to IS1216. This is flanked by two 18-bp inverted repeats (IRs) that are almost identical to those of ISS1 and IS1216. ORF6 (resEJ97) shows strong homology to the resolvase of plasmid pAM373 and up to 40 to 50% homology with the recombinase of several multiresistant plasmids and transposons from Staphylococcus aureus and E. faecalis. These data suggest that EJ97 could represent a new class of bacteriocins with a novel secretion mechanism and that the whole structure could be a composite transposon. Furthermore, two additional gene clusters were found: one cluster is probably related to the region responsible for the replication of plasmid pEJ97, and the second cluster is related to the sex pheromone response. These regions showed a high homology to the corresponding regions of the conjugative plasmids pAM373, pPD1, and pAD1 of E. faecalis, suggesting that they have a common origin. PMID:12620853

  17. Gadolinium-hydrogen ion exchange of zirconium phosphate

    NASA Technical Reports Server (NTRS)

    Liu, D. C.; Power, J. L.

    1972-01-01

    The Gd(+3)/H(+) ion exchange on a commercial zirconium phosphate ion exchanger was investigated in chloride, sulfate, and phosphate solutions of Gd(+3) at gadolinium concentrations of 0.001 to 1 millimole per cc and in the pH range of 0 to 3.5. Relatively low Gd(+3) capacities, in the range of 0.01 to 0.1 millimole per g of ion exchanger were found at room temperature. A significant difference in Gd(+3) sorption was observed, depending on whether the ion exchanger was converted from initial conditions of greater or lesser Gd(+3) sorption than the specific final conditions. Correlations were found between decrease in Gd(+3) capacity and loss of exchanger phosphate groups due to hydrolysis during washing and between increase in capacity and treatment with H3PO4. Fitting of the experimental data to ideal ion exchange equilibrium expressions indicated that each Gd(+3) ion is sorbed on only one site of the ion exchanger. The selectivity quotient was determined to be 2.5 + or - 0.4 at room temperature on gadolinium desorption in chloride solutions.

  18. Characterization of zirconium thin films deposited by pulsed laser deposition

    NASA Astrophysics Data System (ADS)

    Liu, Wei; Wan, Jing-Ping; Cai, Wu-Peng; Liang, Jian-Hua; Zhou, Xiao-Song; Long, Xing-Gui

    2014-09-01

    Zirconium (Zr) thin films deposited on Si (100) by pulsed laser deposition (PLD) at different pulse repetition rates are investigated. The deposited Zr films exhibit a polycrystalline structure, and the X-ray diffraction (XRD) patterns of the films show the ? Zr phase. Due to the morphology variation of the target and the laser—plasma interaction, the deposition rate significantly decreases from 0.0431 Å/pulse at 2 Hz to 0.0189 Å/pulse at 20 Hz. The presence of droplets on the surface of the deposited film, which is one of the main disadvantages of the PLD, is observed at various pulse repetition rates. Statistical results show that the dimension and the density of the droplets increase with an increasing pulse repetition rate. We find that the source of droplets is the liquid layer formed under the target surface. The dense nanoparticles covered on the film surface are observed through atomic force microscopy (AFM). The root mean square (RMS) roughness caused by valleys and islands on the film surface initially increases and then decreases with the increasing pulse repetition rate. The results of our investigation will be useful to optimize the synthesis conditions of the Zr films.

  19. Improved Yttrium and Zirconium Abundances in Metal-Poor Stars

    NASA Astrophysics Data System (ADS)

    Violante, Renata; Biemont, E.; Cowan, J. J.; Sneden, C.

    2012-01-01

    Abstract We present new abundances of the lighter n-capture elements, Yttrium (Z=39) and Zirconium (Z=40) in the very metal poor, r-process rich stars BD+17 3248 and HD 221170. Very accurate abundances were obtained by use of the new transition probabilities for Y II published by Biémont et al. 2011, and Zr II by Malcheva et al. 2006, and by expanding the number of transitions employed for each element. For example, in BD+17 3248, we find log ???????=-0.03 +/- 0.03 (?????=0.15, from 23 lines) for Y II. As for Zr II, log ??????? = 0.65 +/- 0.03 (????? = 0.1, from 13 lines). The resulting abundance ratio is log ??????? [Y/Zr] = -0.68 +/- 0.05. The results for HD 221170 are in accord with those of BD+17 3248. The quantity of lines used to form the abundance means has increased significantly since the original studies of these stars, resulting in more trustworthy abundances. These observed abundance ratios are in agreement with an r-process-only value predicted from stellar models, but is under-abundant compared to an empirical model derived from direct analyses of meteoritic material. This ambiguity should stimulate further nucleosynthetic analysis to explain this abundance ratio. We would like to extend our gratitude to NSF grant AST-0908978 and the University of Texas Astronomy Department Rex G. Baker, Jr. Endowment for their financial support in this project.

  20. Zirconium umbelliferonephosphate - A luminescent organic-inorganic hybrid nanomaterial

    NASA Astrophysics Data System (ADS)

    Roming, Marcus; Feldmann, Claus

    2011-03-01

    Zirconium umbelliferonephosphate (ZrO(UFP)) is prepared by nucleation in the ionic liquid [MeBu 3N][NTf 2]. According to electron microscopy the resulting nanoparticles exhibit mean particle diameters of about 50 nm. The organic-inorganic hybrid material ZrO(UFP) shows blue emission upon UV-excitation. Luminescence originates from the organic dye and is highly intense due to the molar amount of luminescent centers per nanoparticle. The as-prepared material turns out to be non-crystalline. Therefore, its chemical composition is validated by infrared spectroscopy, thermogravimetry, energy-dispersive X-ray analysis and elemental analysis. The results (i.e., thermal decomposition, Zr:P ratio, C-/H-concentration) are in accordance to the composition of ZrO(UFP). Upon addition of acid phosphatase the luminescence intensity of ZrO(UFP) is significantly increased due to enzymatic hydrolysis accompanied by a release of non-bound umbelliferone. Both aspects - the increase in luminescence intensity as well as the release of umbelliferone - might be of future interest regarding biomedical application of ZrO(UFP) nanoparticles.

  1. Characterization of precipitates in a niobium-zirconium-carbon alloy

    NASA Technical Reports Server (NTRS)

    Grobstein, T. L.; Titran, R. H.

    1986-01-01

    A niobium alloy with 1 percent zirconium and 0.063 percent carbon by weight was investigated in the as-rolled and annealed conditions, and after high-temperature (1350 and 1400 K) exposure with and without an applied stress. In the as-rolled and annealed conditions, large metastable carbides were observed in addition to a regular distribution of small particles. During the high-temperature exposure, the majority of the large carbides were dissolved and a more stable carbide phase formed. This finely dispersed phase had a composition determined to be approximately 70 percent ZrC and approximately 30 percent NbC and showed some evidence of an orientation relationship with the matrix. The precipitates appeared to coarsen slightly after approximately 5000 hr exposure in the presence of an applied stress resulted in a decrease in the size and in the interparticle spacing of the stable precipitates. However, the composition of the precipitate phase and its ability to pin dislocations were not affected by the temperature or stress conditions.

  2. Fracture Resistance of a Zirconium Alloy with Reoriented Hydrides

    NASA Astrophysics Data System (ADS)

    Chan, Kwai S.; He, Xihua; Pan, Yi-Ming

    2015-01-01

    Zirconium alloy cladding materials typically contain circumferential hydrides that may be reoriented to align along the radial direction when the cladding tubes are heated above and then cooled below the solvus temperature. The objectives of this study were to investigate the critical stress levels required to cause hydride reorientation (HRT) and to characterize the fracture resistance of Zircaloy-2 after hydride reorientation. HRT heat-treatment was performed on hydrogen-charged Zircaloy-2 specimens at 593 K (320 °C) or 623 K (350 °C) for 1 to 2 hours, followed by cooling to 473 K (200 °C). Fracture testing was conducted on hydride-reoriented three-point bend specimens at 473 K (200 °C) using an in situ loading stage inside a scanning electron microscope. Direct observations indicated that the reoriented hydrides, which ranged from ?1 to 22 ?m in lengths, were more prone to fracture at larger sizes (>10 ?m) compared to smaller sizes (<0.5 ?m). The reoriented hydrides reduced fracture resistance through a void nucleation, growth, and coalescence process at the crack tip. The resulting crack-resistance curves for Zircaloy-2 with reoriented hydrides decrease from 38 to 21 MPa(m)1/2 with increasing hydrogen contents from 51 to 1265 wt ppm hydrogen.

  3. The effect of zirconium implantation on the structure of sapphire

    SciTech Connect

    Sina, Younes [University of Tennessee, Knoxville (UTK); McHargue, Carl J [University of Tennessee, Knoxville (UTK); Duscher, Gerd [University of Tennessee, Knoxville (UTK); Zhang, Yanwen [ORNL

    2012-01-01

    The effect of zirconium implantation on the structure of sapphire was investigated by 175 keV Zr implantation at room temperature to a fluence of 4 1016 ions/cm2 into sapphire single crystals. Samples were examined by several experimental techniques: Rutherford backscattering spectroscopy along a channeling direction (RBS-C), electron-energy loss spectroscopy (EELS), and Z-contrast images obtained in an aberration-corrected scanning transmission electron microscope. Range and deposited energy were simulated with SRIM-2008.04. The Z-contrast images from transmission electron microscope indicated: a near surface damaged layer ~30 nm thick, a subsurface region exhibiting "random" de-channeling ~52 nm thick, and a deeper damaged, crystalline zone ~64 nm thick. The RBS-C spectra confirmed the presence of these three regions. The two damaged regions contained high concentrations of as yet unresolved defect clusters. The intermediate region contained Zr-clusters embedded in an "amorphous" matrix that exhibited short-range order corresponding to -Al2O3, i.e., a defective spinel structure. The EELS measurements show that the amorphous region is deficient in oxygen.

  4. Strain effects on oxygen transport in tetragonal zirconium dioxide

    SciTech Connect

    Xian-Ming Bai; Yongfeng Zhang; Michael R. Tonks

    2013-11-01

    Temperature accelerated dynamics and molecular dynamics simulations are used to investigate the strain effects on oxygen interstitial and vacancy migration in tetragonal zirconium dioxide. At zero external strain, the anisotropic migration mechanisms of oxygen defects are characterized. At non-zero strains, both the crystal structure and defect migration barriers are modified by strain. Under compressive strains, the defect migration barrier increases with the increasing strain for both interstitials and vacancies. The crystal structure transforms from a tetragonal to a nearly cubic fluorite structure. Accordingly, the defect migration becomes nearly isotropic. Under dilative strains, the migration barrier first decreases then increases with increasing strain for both types of defects. The tetragonal phase transforms to a lower symmetry structure that is close to the orthorhombic phase. In turn, the defect migration becomes highly anisotropic. Under both compressive and dilative strains, interstitials respond to strain more strongly than vacancies. At small dilative strains, an oxygen interstitial has comparable diffusivity to a vacancy, suggesting that both types of defects can contribute to oxygen transport, if they are present. Although currently no previous result is available to validate oxygen interstitial diffusion behavior, the trend of strain effects on oxygen vacancy diffusion is in good agreement with available experimental and theoretical studies in the literature.

  5. Electrospun poly (vinyl alcohol)/ alpha-zirconium phosphate nanocomposite fibers

    NASA Astrophysics Data System (ADS)

    Lizu, Monira

    Poly (vinyl alcohol) (PVA)/alpha-zirconium phosphate (ZrP) polymer nanocomposite (PNC) fibers were successfully prepared via the simple and low-cost electrospinning process. ZrP nanoparticles with two different dimensions, i.e., ZrP-500 with a lateral dimension of ca. 320 nm and an aspect ratio of ca. 500, and ZrP-1500 with a lateral dimension of ca. 950 nm and an aspect ratio of ca. 1500, were utilized to illustrate the size effect on the electrospun nanofibers. In order to obtain defect-free, uniform polymer nanocomposite fibers, a number of parameters including polymer concentration, feed rate, applied voltage and working distance between the needle tip and the fiber collecting substrate were investigated. Scanning electron microscopy (SEM) morphological analysis showed smooth and nonwoven electrospun nanofiber mat. Strong intermolecular interactions between the PVA matrix and the included ZrP nanofillers were revealed by the attenuated total reflectance Fourier transform infrared spectroscopy (ATR-FTIR). The incorporation of ZrP nanofillers drastically improved the thermal stability of the PNC fibers. TGA results demonstrated a clear thermal stability dependence on the aspect ratio of the crystalline ZrP nanofillers. The degradation temperature was increased by 90 °C for the ZrP-1500 and 60 °C for ZrP-500 when the loading level was increased from 1% to 5%. Furthermore, the viscoelastic properties of the PNC solutions were studied by rheometer.

  6. High Purity Zirconium Tetrafluoride For Fluoride Glass Applications

    NASA Astrophysics Data System (ADS)

    Withers, Howard P.; Monk, V. A.; Cooper, G. A.

    1989-06-01

    A totally anhydrous process has been developed for the preparation of high purity zirconium tetrafluoride for use in low loss fluoride glass applications. The ZrF4 purityis 99.99997% with respect to all transition elements (excluding HO based on analysis by spark source mass spectrometry (SSMS) and graphite furnace/atomic absorption spectroscopy (GF/AA). The only transition elements detected by these techniques were Fe, Ni and Cr, while Co and Cu were consistently below the detection limits. The anhydrous nature of the process, which is strictly maintained by the choice of reactants, affords product with very low oxide and hydroxide content. Total oxygen concentrations of less than 10 ppm have been measured by the inert gas fusion technique. A ZBLAN glass composition prepared using this ZrF4 showed extremely low UV absorption having an absorption constant of 1 cm-1 at 198 nm. ZrF4 from this process was also used in a ZBLAN glass fiber whose minimum optical loss was measured at 6.3 dB/km over 150 meters of fiber. The process is straightforward to scale up and has also been demonstrated to be useful for the preparation of HfF4, BaF2, A1F3 and LaF3.

  7. Structural evolution of zirconium carbide under ion irradiation

    NASA Astrophysics Data System (ADS)

    Gosset, D.; Dollé, M.; Simeone, D.; Baldinozzi, G.; Thomé, L.

    2008-02-01

    Zirconium carbide is one of the candidate materials to be used for some fuel components of the high temperature nuclear reactors planned in the frame of the Gen-IV project. Few data exist regarding its behaviour under irradiation. We have irradiated ZrC samples at room temperature with slow heavy ions (4 MeV Au, fluence from 10 11 to 5 × 10 15 cm -2) in order to simulate neutron irradiations. Grazing incidence X-Ray diffraction (GIXRD) and transmission electron microscopy (TEM) analysis have been performed in order to study the microstructural evolution of the material versus ion fluence. A high sensitivity to oxidation is observed with the formation of zirconia precipitates during the ion irradiations. Three damage stages are observed. At low fluence (<10 12 cm -2), low modifications are observed. At intermediate fluence, high micro-strains appear together with small faulted dislocation loops. At the highest fluence (>10 14 cm -2), the micro-strains saturate and the loops coalesce to form a dense dislocation network. No other structural modification is observed. The material shows a moderate cell parameter increase, corresponding to a 0.6 vol.% swelling, which saturates around 10 14 ions/cm 2, i.e., a few Zr dpa. As a result, in spite of a strong covalent bonding component, ZrC seems to have a behaviour under irradiation close to cubic metals.

  8. Microstructure and mechanical properties of proton irradiated zirconium carbide

    NASA Astrophysics Data System (ADS)

    Yang, Yong; Dickerson, Clayton A.; Swoboda, Hannah; Miller, Brandon; Allen, Todd R.

    2008-09-01

    Zirconium carbide is a candidate ceramic being considered for metal-carbide-base composite-type fuels, as well as for an alternative coating material for TRISO particle fuels. Ensuring adequate mechanical properties and dimensional stability in response to radiation is a key part in developing a practical ZrC-base fuel. The existing available radiation response data for ZrC is limited and insufficient. In the present study, ZrC was irradiated with a 2.6 MeV proton beam at 800 °C to doses of 0.7 and 1.5 dpa. Following radiation, the radiation induced damage microstructure is comprised of a high density of nanometer-sized Frank loops, but no irradiation induced amorphization, voids, or precipitates were observed. A slight lattice expansion was found in the irradiated ZrC, in good agreement with the reported results from neutron irradiation. The changes in microhardness and fracture toughness properties induced in the irradiated samples were measured using indentation techniques. The hardness and the fracture toughness both increase with increasing radiation dose.

  9. Effects of fast neutron irradiation on zirconium carbide

    NASA Astrophysics Data System (ADS)

    Snead, Lance L.; Katoh, Yutai; Kondo, Sosuke

    2010-04-01

    High-purity zone refined zirconium carbide has been fast neutron irradiated in the dose and temperature range of 1-10 × 10 25 N/m 2 ( E > 0.1 MeV) and 635-1480 °C, respectively. Non-irradiated and as-irradiated properties were measured including the lattice parameter, hardness and elastic modulus as determined through nano-indentation, thermal conductivity, and indentation fracture toughness. The effects of neutron irradiation on the microstructure were also determined though using transmission electron microscopy. The general finding of this paper, limited to this particular zone refined ZrC of nominal C/Zr ratio of 0.93, is that this ceramic is quite stable under neutron irradiation in the temperature and dose range studied. Measurement of lattice parameter before and after irradiation indicated a lack of significant crystalline strain due to irradiation. Only modest changes were observed in the mechanical properties of hardness, elastic modulus, and indentation fracture toughness. The thermal conductivity underwent a slight reduction near 1000 °C irradiation, though was essentially unchanged for 1300-1480 °C irradiation. Transmission electron microscopy revealed black-spot-type defects (likely Frank or other small loops) for irradiation at 670 °C, maturing to faulted Frank loops at 1280 °C. As the irradiation temperature increased from 1280 °C to the highest irradiation temperature, of 1496 °C, a transition to prismatic loops occurs.

  10. Properties of zirconium carbide for nuclear fuel applications

    NASA Astrophysics Data System (ADS)

    Katoh, Yutai; Vasudevamurthy, Gokul; Nozawa, Takashi; Snead, Lance L.

    2013-10-01

    Zirconium carbide (ZrC) is a potential coating, oxygen-gettering, or inert matrix material for advanced high temperature reactor fuels. ZrC has demonstrated attractive properties for these fuel applications including excellent resistance against fission product corrosion and fission product retention capabilities. However, fabrication of ZrC results in a range of stable sub-stoichiometric and carbon-rich compositions with or without substantial microstructural inhomogeneity, textural anisotropy, and a phase separation, leading to variations in physical, chemical, thermal, and mechanical properties. The effects of neutron irradiation at elevated temperatures, currently only poorly understood, are believed to be substantially influenced by those compositional and microstructural features further adding complexity to understanding the key ZrC properties. This article provides a survey of properties data for ZrC, as required by the United States Department of Energy's advanced fuel programs in support of the current efforts toward fuel performance modeling and providing guidance for future research on ZrC for fuel applications.

  11. Zirconium carbide thin films deposited by pulsed laser ablation

    NASA Astrophysics Data System (ADS)

    D'Alessio, L.; Santagata, A.; Teghil, R.; Zaccagnino, M.; Zaccardo, I.; Marotta, V.; Ferro, D.; De Maria, G.

    2000-12-01

    A study of the laser ablation and deposition of zirconium carbide has been carried out in our laboratory. The target has been vaporised by a doubled Nd:YAG laser and the ablation plume has been characterised by time-of-flight mass spectrometry, emission spectroscopy and ultrafast imaging performed by an Intensified Coupled Charge Device (ICCD). The results show a single ablation mechanism in the whole range of laser fluence used in the experiments (0.5-15 J/cm2) and this is quite different from the case of TiC. The gas phase data are confirmed by the analysis of the films deposited on oriented silicon. In fact, by X-ray diffraction and subsequent XPS analysis, their composition is fluence independent leading to films with constant characteristics on a large range of experimental conditions. The difference between ZrC and TiC ablation mechanisms may be explained in terms of chemical-physical properties and thermodynamic considerations which can also clarify the gas phase composition.

  12. The thermophysical properties of calcium and barium zirconium phosphate

    NASA Astrophysics Data System (ADS)

    Gregg, Daniel J.; Karatchevtseva, Inna; Triani, Gerry; Lumpkin, Gregory R.; Vance, Eric R.

    2013-10-01

    The thermophysical and structural properties of calcium and barium zirconium phosphate ceramics (CZP and BZP) have been investigated for their potential candidacy as actinide hosts for inert matrix fuels (IMF) in nuclear reactors. These phosphate ceramics, which can accommodate minor actinides as well as the resulting fission products, are found to be thermally stable to 1600 °C in air, however they begin to decompose in an inert atmosphere above approximately 1400 °C. The heat capacity, thermal conductivity and bulk thermal-expansion were measured from room temperature up to 1200 °C. Structural changes in this temperature region as well as the anisotropic thermal-expansion behaviour were studied using high-temperature X-ray diffraction. A phase change from R-3 to R-3c was identified for Ba0.5Zr2(PO4)3 near 880 °C. The thermal conductivity for these ceramics at 1000 °C was found to be 1.0 W m-1 K-1, a relatively low thermal conductivity that was increased to 5.0 W m-1 K-1 at 1000 °C for BZP:Ni (25:75 mass ratio) cermet composites.

  13. Synthesis and Characterization of Zirconium Tungstate Ultra-Thin Fibers

    SciTech Connect

    Zhang, Lifeng [South Dakota School of Mines and Technology; Howe, Jane Y [ORNL; Fong, Hao [South Dakota School of Mines and Technology; Zhang, Yan [Anhui Normal University, People's Republic of China

    2009-01-01

    This study reports an innovative method of electrospinning followed by pyrolysis to synthesize zirconium tungstate (ZrW2O8), a material with negative coefficient of thermal expansion (CTE), in ultra-thin fiber form. Morphologies and microstructures of the as-electrospun precursor fibers, the heat-treated intermediate fibers, and the final ZrW2O8 ultra-thin fibers were characterized by SEM, XRD, and TEM. The ZrW2O8 ultra-thin fibers had diameters in the sub-micrometer range with aspect ratios larger than 100; these fibers were polycrystalline, and consisted of single crystalline ZrW2O8 crystallites with sizes of 30-50 nm and surface roughness of several nanometers. The ZrW2O8 ultra-thin fibers are expected to outperform spherically, cylindrically, and/or irregularly shaped polycrystalline ZrW2O8 particles for the development of composites with precisely controlled CTEs. Additionally, this reported method could be utilized as a general approach to convert nano-scaled inorganic particles into fibers.

  14. The effect of zirconium implantation on the structure of sapphire

    NASA Astrophysics Data System (ADS)

    Sina, Y.; McHargue, C. J.; Duscher, G.; Zhang, Y.

    2012-09-01

    The effect of zirconium implantation on the structure of sapphire was investigated by 175 keV Zr implantation at room temperature to a fluence of 4 × 1016 ions/cm2 into sapphire single crystals. Samples were examined by several experimental techniques: Rutherford backscattering spectroscopy along a channeling direction (RBS-C), electron-energy loss spectroscopy (EELS), and Z-contrast images obtained in an aberration-corrected scanning transmission electron microscope. Range and deposited energy were simulated with SRIM-2008.04. The Z-contrast images from transmission electron microscope indicated: a near surface damaged layer ˜30 nm thick, a subsurface region exhibiting "random" de-channeling ˜52 nm thick, and a deeper damaged, crystalline zone ˜64 nm thick. The RBS-C spectra confirmed the presence of these three regions. The two damaged regions contained high concentrations of as yet unresolved defect clusters. The intermediate region contained Zr-clusters embedded in an "amorphous" matrix that exhibited short-range order corresponding to ?-Al2O3, i.e., a defective spinel structure. The EELS measurements show that the amorphous region is deficient in oxygen.

  15. 46 CFR 97.37-50 - Ventilation alarm failure.

    Code of Federal Regulations, 2012 CFR

    2012-10-01

    ...2012-10-01 2012-10-01 false Ventilation alarm failure. 97.37-50 Section...Equipment, Etc. § 97.37-50 Ventilation alarm failure. (a) The alarm...which indicates the loss of required ventilation in spaces specially suitable for...

  16. 46 CFR 97.37-50 - Ventilation alarm failure.

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ...2010-10-01 2010-10-01 false Ventilation alarm failure. 97.37-50 Section...Equipment, Etc. § 97.37-50 Ventilation alarm failure. (a) The alarm...which indicates the loss of required ventilation in spaces specially suitable for...

  17. 46 CFR 97.37-50 - Ventilation alarm failure.

    Code of Federal Regulations, 2011 CFR

    2011-10-01

    ...2011-10-01 2011-10-01 false Ventilation alarm failure. 97.37-50 Section...Equipment, Etc. § 97.37-50 Ventilation alarm failure. (a) The alarm...which indicates the loss of required ventilation in spaces specially suitable for...

  18. 46 CFR 97.37-50 - Ventilation alarm failure.

    Code of Federal Regulations, 2014 CFR

    2014-10-01

    ...2014-10-01 2014-10-01 false Ventilation alarm failure. 97.37-50 Section...Equipment, Etc. § 97.37-50 Ventilation alarm failure. (a) The alarm...which indicates the loss of required ventilation in spaces specially suitable for...

  19. 46 CFR 97.37-50 - Ventilation alarm failure.

    Code of Federal Regulations, 2013 CFR

    2013-10-01

    ...2013-10-01 2013-10-01 false Ventilation alarm failure. 97.37-50 Section...Equipment, Etc. § 97.37-50 Ventilation alarm failure. (a) The alarm...which indicates the loss of required ventilation in spaces specially suitable for...

  20. 7 CFR 97.150 - Right to be represented.

    Code of Federal Regulations, 2012 CFR

    2012-01-01

    7 ? Agriculture ? 3 ? 2012-01-01 ? 2012-01-01 ? false ? Right to be represented. ? 97.150 ? Section 97.150 ? Agriculture ? Regulations of the Department of Agriculture (Continued) ? AGRICULTURAL MARKETING SERVICE (Standards, Inspections, Marketing Practices), DEPARTMENT OF AGRICULTURE (CONTINUED)...

  1. 7 CFR 97.142 - For testing or increase.

    Code of Federal Regulations, 2012 CFR

    2012-01-01

    7 ? Agriculture ? 3 ? 2012-01-01 ? 2012-01-01 ? false ? For testing or increase. ? 97.142 ? Section 97.142 ? Agriculture ? Regulations of the Department of Agriculture (Continued) ? AGRICULTURAL MARKETING SERVICE (Standards, Inspections, Marketing Practices), DEPARTMENT OF AGRICULTURE (CONTINUED)...

  2. Role of p97/VCP (Cdc48) in genome stability

    PubMed Central

    Vaz, Bruno; Halder, Swagata; Ramadan, Kristijan

    2013-01-01

    Ubiquitin-dependent molecular chaperone p97, also known as valosin-containing protein (VCP) or Cdc48, is an AAA ATPase involved in protein turnover and degradation. p97 converts its own ATPase hydrolysis into remodeling activity on a myriad of ubiquitinated substrates from different cellular locations and pathways. In this way, p97 mediates extraction of targeted protein from cellular compartments or protein complexes. p97-dependent protein extraction from various cellular environments maintains cellular protein homeostasis. In recent years, p97-dependent protein extraction from chromatin has emerged as an essential evolutionarily conserved process for maintaining genome stability. Inactivation of p97 segregase activity leads to accumulation of ubiquitinated substrates on chromatin, consequently leading to protein-induced chromatin stress (PICHROS). PICHROS directly and negatively affects multiple DNA metabolic processes, including replication, damage responses, mitosis, and transcription, leading to genotoxic stress and genome instability. By summarizing and critically evaluating recent data on p97 function in various chromatin-associated protein degradation processes, we propose establishing p97 as a genome caretaker. PMID:23641252

  3. 40 CFR 97.387 - Change in regulatory status.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ...CAIR NOX AND SO2 TRADING PROGRAMS CAIR NOX Ozone Season Opt-in Units § 97.387 Change...status. (a) Notification. If a CAIR NOX Ozone Season opt-in unit becomes a CAIR NOX Ozone Season unit under § 97.304, then...

  4. 46 CFR 97.01-2 - Incorporation by reference.

    Code of Federal Regulations, 2012 CFR

    2012-10-01

    ...12-616260-01 (1996)—97.36-1 International Maritime Organization (IMO) Publications Section, 4 Albert Embankment, London, SE1 7SR United Kingdom Resolution A.654(16), Graphical Symbols for Fire Control Plans—97.36-1 [CGD...

  5. AC '97 Codec with National 3D Sound General Description

    E-print Network

    Bakos, Jason D.

    mono inputs, each of which has separate gain, attenuation and mute control. In addition, the LM4540, fixed rate se- rial bus for connection to the digital AC '97 Controller. The separation of the analog/D Dynamic Range 90dB (typ) Features n Audio Codec '97 compliant n Stereo 18-Bit A/D's and D/A's with 128X

  6. Colleges and Universities. Education Digest, 1996-97.

    ERIC Educational Resources Information Center

    Khanna, Devki, Comp.; McCormick, Marcia, Comp.

    This report provides statistical data on higher education in Pennsylvania in 1996-97. Thirty-four tables and 8 figures provide data on basic student charges (including data on tuition, room and board, in-state versus out-of-state charges, and average annual increases 1987-88 through 1996-97); fall enrollments (including data by institution, age,…

  7. 40 CFR 97.387 - Change in regulatory status.

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ...AND SO2 TRADING PROGRAMS CAIR NOX Ozone Season Opt-in Units § 97.387 Change in regulatory...a) Notification. If a CAIR NOX Ozone Season opt-in unit becomes a CAIR NOX Ozone Season unit under § 97.304, then the CAIR...

  8. 40 CFR 97.384 - Opt-in process.

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ...SO2 TRADING PROGRAMS CAIR NOX Ozone Season Opt-in Units § 97.384 Opt-in...is withdrawn from the CAIR NOX Ozone Season Trading Program in accordance with § 97...which the unit enters the CAIR NOX Ozone Season Trading Program under §...

  9. 40 CFR 97.387 - Change in regulatory status.

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ...AND SO2 TRADING PROGRAMS CAIR NOX Ozone Season Opt-in Units § 97.387 Change in regulatory...a) Notification. If a CAIR NOX Ozone Season opt-in unit becomes a CAIR NOX Ozone Season unit under § 97.304, then the CAIR...

  10. 40 CFR 97.387 - Change in regulatory status.

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ...AND SO2 TRADING PROGRAMS CAIR NOX Ozone Season Opt-in Units § 97.387 Change in regulatory...a) Notification. If a CAIR NOX Ozone Season opt-in unit becomes a CAIR NOX Ozone Season unit under § 97.304, then the CAIR...

  11. 40 CFR 97.384 - Opt-in process.

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ...SO2 TRADING PROGRAMS CAIR NOX Ozone Season Opt-in Units § 97.384 Opt-in...is withdrawn from the CAIR NOX Ozone Season Trading Program in accordance with § 97...which the unit enters the CAIR NOX Ozone Season Trading Program under §...

  12. 40 CFR 97.384 - Opt-in process.

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ...SO2 TRADING PROGRAMS CAIR NOX Ozone Season Opt-in Units § 97.384 Opt-in...is withdrawn from the CAIR NOX Ozone Season Trading Program in accordance with § 97...which the unit enters the CAIR NOX Ozone Season Trading Program under §...

  13. 40 CFR 97.387 - Change in regulatory status.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ...CAIR NOX AND SO2 TRADING PROGRAMS CAIR NOX Ozone Season Opt-in Units § 97.387 Change...status. (a) Notification. If a CAIR NOX Ozone Season opt-in unit becomes a CAIR NOX Ozone Season unit under § 97.304, then...

  14. 40 CFR 97.142 - CAIR NOX allowance allocations.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ...97 percent for a control period during 2015 and thereafter, of the tons of NOX emissions...and 3 percent for a control period in 2015 and thereafter, of the amount of tons...97 percent for a control period during 2015 and thereafter, of the amount of...

  15. 40 CFR 97.142 - CAIR NOX allowance allocations.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ...97 percent for a control period during 2015 and thereafter, of the tons of NOX emissions...and 3 percent for a control period in 2015 and thereafter, of the amount of tons...97 percent for a control period during 2015 and thereafter, of the amount of...

  16. 40 CFR 97.142 - CAIR NOX allowance allocations.

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ...97 percent for a control period during 2015 and thereafter, of the tons of NOX emissions...and 3 percent for a control period in 2015 and thereafter, of the amount of tons...97 percent for a control period during 2015 and thereafter, of the amount of...

  17. Cold neutron prompt gamma activation analysis, a non-destructive technique for hydrogen level assessment in zirconium alloys

    E-print Network

    Motta, Arthur T.

    assessment in zirconium alloys Adrien Couet a, , Arthur T. Motta a , Robert J. Comstock b , Rick L. Paul c to quantitatively assess hydrogen concentration in zirconium alloys. The technique, called Cold Neutron Prompt Gamma alloy nuclear fuel cladding and the associated hydrogen pick-up can become a life-limiting degradation

  18. Identification of anisotropic Hill criteria from the channel die compression test. Application to a normal anisotropy of zirconium 702alpha

    Microsoft Academic Search

    A. Gavrus; H. Francillette

    2003-01-01

    During the last years the study of the plastic deformation modes and the anisotropic mechanical behavior of zirconium alloys have been the subject of many investigations. This paper deals with a phenomenological identification of an anisotropic Hill constitutive equation of zirconium 702alpha samples using channel die compression at room temperature. Generally, by considering the different possible orientations of the samples

  19. Bull. Fr. Pche Piscic. (2003) 370-371 : 97-114 --97 --MANAGEMENT OF THE WHITE-CLAWED CRAYFISH

    E-print Network

    Paris-Sud XI, Université de

    Bull. Fr. Pêche Piscic. (2003) 370-371 : 97-114 -- 97 -- MANAGEMENT OF THE WHITE-CLAWED CRAYFISH Accepted December 22, 2003 ABSTRACT In France, the distribution of the white-clawed crayfish; eight of the nine brooks harbour white- clawed crayfish populations. Two sampling sites are surveyed per

  20. HP Laboratories 2/5/97 Hiro:Documents:Giordano Beretta:Research:EI 97:3016-15:JPEG overheads

    E-print Network

    Beretta, Giordano

    HP Laboratories 2/5/97 Hiro:Documents:Giordano Beretta:Research:EI 97:3016-15:JPEG overheads 0 Beretta, Vasudev Bhaskaran, Konstantinos Konstantinides, Balas K. Natarajan Hewlett-Packard Laboratories 1501 Page Mill Road Palo Alto, CA 94304­1126 http://www.hpl.hp.com/personal/Giordano_Beretta #12;HP

  1. J. Phys. II France 6 (1996) 97-104 JANUARY 1996, PAGE 97 The Elastohydrodynamic Lubrication Force in the Squeeze

    E-print Network

    Paris-Sud XI, Université de

    1996-01-01

    J. Phys. II France 6 (1996) 97-104 JANUARY 1996, PAGE 97 The Elastohydrodynamic Lubrication Force's theory of deformation and lubrication theory. An expression for the lubrication force analytical on the lubrication force is demonstrated. Further, the lubrication force with a pressure dependent viscosity

  2. CLNS 97/1498, HUTP97/A032, NUB 3162 A Review of ThreeFamily Grand Unified String Models

    E-print Network

    the string vacuum in which we live. This approach has been known as ``superstring phenomenology''. The latterCLNS 97/1498, HUTP­97/A032, NUB 3162 A Review of Three­Family Grand Unified String Models Zurab such models which is organized to aid analysis of their phenomenological properties. We compute tree

  3. Containerless Liquid to Solid Nucleation Pathways in Two Representative Grades of Commercially Available Zirconium

    NASA Technical Reports Server (NTRS)

    Rulison, A. J.; Rhim, W.-K.; Bayuzick, R.; Hofmeister, W.; Morton, C.

    1997-01-01

    Experimental measurements were conducted to determine the solid metal nucleation pathways of radiatively cooling, molten zirconium spheres of two different commercially available purity grades in a high-vacuum, high-temperature electrostatic levitator. The ensemble distribution of maximum undercooling temperatures was interpreted using Poisson statistics to determine the temperature dependence of the solid metal nucleation rate. For a sample of nominally 99.95% pure zirconium, the results are consistent with heterogeneous solid metal nucleation either on static catalyst particles at least approx. 30 nm diameter or on a surface coating. For a sample of nominally 99% pure zirconium, however, it appears that heterogeneous solid metal nucleation occurred either on a polydispersion of approx. 10 nm (mean diameter) static catalyst particles or on dynamic catalyst particles that precipitated from a solution that became supersaturated as the melt cooled.

  4. Hydrogen Embrittlement in Zirconium: a Quasi-Continuum Density Functional Theory Study

    NASA Astrophysics Data System (ADS)

    Peng, Q.

    2012-02-01

    The hydrogen embrittlement in Zirconium becomes a very important and emergent issue for academia, industry and policy makers as a result of the Japan nuclear accident. The hydride formation, diffusion and embrittlement in zircolay will impact dramatically on the development of advanced nuclear energy systems, the life time extension of the current nuclear fleet and dry storage of spent nuclear fuel. Quasi-Continuum Density Functional Theory (QCDFT) is a powerful concurrent multiscale method based entirely on density functional theory (DFT) and allows quantum simulations of materials properties of a large system with billions of atoms. Using QCDFT modeling, we found that the presents of hydrogen at the cracktip of zirconium, both on crack surface and in-bulk, will form zirconium hydrides and embrittle the system. The concentration of hydrogen and orientation of crack plays important roles in such embrittlement. The mechanism of hydrogen embrittlement under various loading conditions will be discussed.

  5. Hypersensitivity pneumonitis and exposure to zirconium silicate in a young ceramic tile worker.

    PubMed

    Liippo, K K; Anttila, S L; Taikina-Aho, O; Ruokonen, E L; Toivonen, S T; Tuomi, T

    1993-10-01

    We describe a nonsmoking ceramic tile worker 25 yr of age who developed a worsening dry cough and dyspnea after 3.5 yr as a sorter and glazer of tiles. Open lung biopsy revealed an intense granulomatous interstitial pneumonia with mild fibrosis, compatible with hypersensitivity pneumonitis, and numerous very small birefringent crystals around the terminal airways and occasionally in granulomas. Pulmonary particle analysis revealed an inhaled dust burden nearly 100-fold the normal background level, mainly consisting of clay minerals and zirconium silicate. The patient had no history or clinical or laboratory findings suggesting any organic etiologic agent. A sarcoid granulomatosis type of chronic pulmonary hypersensitivity reaction is known after long-term exposure to zirconium, but this case demonstrates that zirconium can also cause an acute and fulminant allergic alveolitislike hypersensitivity reaction. PMID:8214930

  6. Theoretical study of the reaction between 2,2???,4???-trihydroxyazobenzene-5-sulfonic acid and zirconium

    USGS Publications Warehouse

    Fletcher, M.H.

    1960-01-01

    Zirconium reacts with 2,2???,4???-trihydroxyazobenzene-5-sulfonic acid in acid solutions to Form two complexes in which the ratios of dye to zirconium are 1 to 1 and 2 to 1. Both complexes are true chelates, with zirconium acting as a bridge between the two orthohydroxy dye groups. Apparent equilibrium constants for the reactions to form each of the complexes are determined. The reactions are used as a basis for the determination of the active component in the dye and a graphical method for the determination of reagent purity is described. Four absorption spectra covering the wave length region from 350 to 750 m?? are given, which completely define the color system associated with the reactions in solutions where the hydrochloric acid concentration ranges from 0.0064N to about 7N.

  7. Review of Cernox™ (Zirconium Oxy-Nitride) Thin-Film Resistance Temperature Sensors

    NASA Astrophysics Data System (ADS)

    Courts, S. Scott; Swinehart, Philip R.

    2003-09-01

    Cernox™ resistance thermometers were commercially introduced in 1993. The Cernox™ temperature-sensing element is fabricated from zirconium reactively sputtered in a nitrogen-oxygen atmosphere. The resulting thin film is comprised of conducting zirconium nitride embedded within a zirconium oxide nonconducting matrix. This material has a negative temperature coefficient of resistance making it useful as a temperature sensor. The ratio of conducting to nonconducting material can be varied to tailor the sensor to a given temperature range. A single device can be fabricated for use from below 0.3 K to 420 K. Cernox™ temperature sensors possess many attributes desirable in a temperature sensor including high sensitivity, excellent short-term and long-term stability, small physical size, fast thermal response and small calibration shifts when exposed to magnetic fields or ionizing radiation. This paper presents a review of Cernox™ temperature sensors with regard to their physical, thermometric and operational properties and environmental effects.

  8. Simulating the corrosion of zirconium alloys in the water coolant of VVER reactors

    NASA Astrophysics Data System (ADS)

    Kritskii, V. G.; Berezina, I. G.; Motkova, E. A.

    2013-07-01

    A model for predicting the corrosion of cladding zirconium alloys depending on their composition and operating conditions is proposed. Laws of thermodynamics and chemical kinetics of the reactions through which the multicomponent zirconium alloy is oxidized in the reactor coolant constitute the physicochemical heart of the model. The developed version of the model is verified against the results obtained from tests of fuel rod claddings made of commercial-grade and experimental zirconium alloys carried out by different researchers under autoclave and reactor conditions. It is shown that the proposed model adequately describes the corrosion of alloys in coolants used at nuclear power stations. It is determined that, owing to boiling of coolant and its acidification in a VVER-1200 reactor, Zr-1% Nb alloys with additions of iron and oxygen must be more resistant to corrosion than the commercial-grade alloy E110.

  9. Determination of fluoride in water - A modified zirconium-alizarin method

    USGS Publications Warehouse

    Lamar, W.L.

    1945-01-01

    A convenient, rapid colorimetric procedure using the zirconium-alizarin indicator acidified with sulfuric acid for the determination of fluoride in water is described. Since this acid indicator is stable indefinitely, it is more useful than other zirconium-alizarin reagents previously reported. The use of sulfuric acid alone in acidifying the zirconium-alizarin reagent makes possible the maximum suppression of the interference of sulfate. Control of the pH of the samples eliminates errors due to the alkalinity of the samples. The fluoride content of waters containing less than 500 parts per million of sulfate and less than 1000 p.p.m. of chloride may be determined within a limit of 0.1 p.p.m. when a 100-ml. sample is used.

  10. Synthesis, Spectroscopic, and Biological Studies on New Zirconium(IV) Porphyrins with Axial Ligand

    PubMed Central

    Bajju, Gauri D.; Devi, Gita; Katoch, Sapna; Bhagat, Madhulika; Deepmala; Ashu; Kundan, Sujata; Anand, Sunil Kumar

    2013-01-01

    A series of parasubstituted tetraphenylporphyrin zirconium(IV) salicylate complexes (SA/5-SSAZr(IV)RTPP, R = p-H, p-CH3, p-NO2, p-Cl, SA = salicylate, and 5-SSA = 5-sulfosalicylate) have been synthesized, and the spectral properties of free base porphyrins, their corresponding metallated, and axially ligated zirconium(IV) porphyrin compounds were compared with each other. A detailed analysis of ultraviolet-visible (UV-vis), proton nulcear magnetic resonance (1H NMR) spectroscopy, infrared (IR) spectroscopy, and elemental analysis suggested the transformation from free base porphyrins to zirconium(IV) porphyrins. The ability of the metal in this complex for extra coordination of solvent molecules was confirmed by ESI-MS spectra. Besides the fluorescence, cyclic voltammetry, and thermogravimetric studies, the complexes were also screened for antimicrobial and anticancer activities. Among all the complexes, 5-SSAZr(p-NO2TPP) shows high antibacterial activity. PMID:24106455

  11. Bayesian model selection validates a biokinetic model for zirconium processing in humans

    PubMed Central

    2012-01-01

    Background In radiation protection, biokinetic models for zirconium processing are of crucial importance in dose estimation and further risk analysis for humans exposed to this radioactive substance. They provide limiting values of detrimental effects and build the basis for applications in internal dosimetry, the prediction for radioactive zirconium retention in various organs as well as retrospective dosimetry. Multi-compartmental models are the tool of choice for simulating the processing of zirconium. Although easily interpretable, determining the exact compartment structure and interaction mechanisms is generally daunting. In the context of observing the dynamics of multiple compartments, Bayesian methods provide efficient tools for model inference and selection. Results We are the first to apply a Markov chain Monte Carlo approach to compute Bayes factors for the evaluation of two competing models for zirconium processing in the human body after ingestion. Based on in vivo measurements of human plasma and urine levels we were able to show that a recently published model is superior to the standard model of the International Commission on Radiological Protection. The Bayes factors were estimated by means of the numerically stable thermodynamic integration in combination with a recently developed copula-based Metropolis-Hastings sampler. Conclusions In contrast to the standard model the novel model predicts lower accretion of zirconium in bones. This results in lower levels of noxious doses for exposed individuals. Moreover, the Bayesian approach allows for retrospective dose assessment, including credible intervals for the initially ingested zirconium, in a significantly more reliable fashion than previously possible. All methods presented here are readily applicable to many modeling tasks in systems biology. PMID:22863152

  12. Solid-phase zirconium and fluoride species in alkaline zircaloy cladding waste at Hanford.

    PubMed

    Reynolds, Jacob G; Huber, Heinz J; Cooke, Gary A; Pestovich, John A

    2014-08-15

    The United States Department of Energy Hanford Site, near Richland, Washington, USA, processed plutonium between 1944 and 1987. Fifty-six million gallons of waste of various origins remain, including waste from removing zircaloy fuel cladding using the so-called Zirflex process. The speciation of zirconium and fluoride in this waste is important because of the corrosivity and reactivity of fluoride as well as the (potentially) high density of Zr-phases. This study evaluates the solid-phase speciation of zirconium and fluoride using X-ray diffraction (XRD) and scanning electron microscopy with energy dispersive spectroscopy (SEM-EDS). Two waste samples were analyzed: one waste sample that is relatively pure zirconium cladding waste from tank 241-AW-105 and another that is a blend of zirconium cladding wastes and other high-level wastes from tank 241-C-104. Villiaumite (NaF) was found to be the dominant fluoride species in the cladding waste and natrophosphate (Na7F[PO4]2 · 19H2O) was the dominant species in the blended waste. Most zirconium was present as a sub-micron amorphous Na-Zr-O phase in the cladding waste and a Na-Al-Zr-O phase in the blended waste. Some zirconium was present in both tanks as either rounded or elongated crystalline needles of Na-bearing ZrO2 that are up to 200 ?m in length. These results provide waste process planners the speciation data needed to develop disposal processes for this waste. PMID:24976128

  13. Bonding of sapphire to sapphire by eutectic mixture of aluminum oxide and zirconium oxide

    NASA Technical Reports Server (NTRS)

    Deluca, J. J. (inventor)

    1979-01-01

    An element comprising sapphire, ruby or blue sapphire can be bonded to another element of such material with a eutectic mixture of aluminum oxide and zirconium oxide. The bonding mixture may be applied in the form of a distilled water slurry or by electron beam vapor deposition. In one embodiment the eutectic is formed in situ by applying a layer of zirconium oxide and then heating the assembly to a temperature above the eutectic temperature and below the melting point of the material from which the elements are formed. The formation of a sapphire rubidium maser cell utilizing eutectic bonding is shown.

  14. Bonding of sapphire to sapphire by eutectic mixture of aluminum oxide and zirconium oxide

    NASA Technical Reports Server (NTRS)

    Deluca, J. J. (inventor)

    1975-01-01

    Bonding of an element comprising sapphire, ruby or blue sapphire to another element of such material with a eutectic mixture of aluminum oxide and zirconium oxide is discussed. The bonding mixture may be applied in the form of a distilled water slurry or by electron beam vapor deposition. In one embodiment the eutectic is formed in situ by applying a layer of zirconium oxide and then heating the assembly to a temperature above the eutectic temperature and below the melting point of the material from which the elements are formed. The formation of a sapphire rubidium maser cell utilizing eutectic bonding is shown.

  15. Thermal Decomposition and Desorption of Diethylamido of Tetrakis (Diethylamido)Zirconium (TDEAZr) on Si(100)

    Microsoft Academic Search

    Joonhee Jeong; Sungwon Lim; Kijung Yong

    2003-01-01

    The thermal decomposition pathway and desorption of diethylamido of tetrakis (diethylamido)zirconium [TDEAZr, Zr(N(C2H5)2) 4] on Si(100) were studied using temperature-programmed desorption (TPD) and X-ray photoelectron spectroscopy (XPS). During TPD experiments, ethylethyleneimine (C2H5N=CHCH3), diethylamine [NH(C2H5)2], acetonitrile (CH3CN), ethylene (C2H4) and hydrogen (H2) desorbed as the main decomposition products of diethylamido, which was chemisorbed on Si(100) through the scission of the zirconium-diethylamido

  16. Methyl iodide as a promoter of the SCC of zirconium alloys in iodine vapour

    NASA Astrophysics Data System (ADS)

    Cox, B.; Haddad, R.

    1986-01-01

    The presence of organic-iodine contaminants, or specifically methyl iodide, in the iodine environment during stress corrosion tests leads to an increased frequency of crack nucleation, and possibly a more rapid crack propagation process. The unusual fractographic features associated with these impurities suggest that they enhance the reduction in the surface energy of zirconium, cause an instability in the propagating crack front, and possibly enhance the rate of reaction to form zirconium iodides. These impurities are the most potent catalysts of iodine-induced cracking so far identified, although methyl iodide alone cannot initiate cracking.

  17. Stress corrosion cracking of zirconium cladding tubes: I. Proximate local SCC testing method

    NASA Astrophysics Data System (ADS)

    Rozhnov, A. B.; Belov, V. A.; Nikulin, S. A.; Khanzhin, V. G.

    2010-10-01

    The stress corrosion cracking (SCC) methods of testing zirconium cladding tubes are analyzed. A proximate method is proposed for estimating SCC of fuel claddings claddings in a iodine-containing environment with a limited contact zone between a metal and corrosive medium and simultaneous measurement of acoustic emission (AE) from forming corrosion defects. Criteria of estimating the SCC resistance of the tubes are proposed from measured AE and corrosion damage of the tube material. The results of local SCC tests of cladding tubes of E110 and E635 zirconium alloys are presented.

  18. Zirconium-modified materials for selective adsorption and removal of aqueous arsenic

    DOEpatents

    Zhao, Hongting; Moore, Robert C.

    2004-11-30

    A method, composition, and apparatus for removing contaminant species from an aqueous medium comprising: providing a material to which zirconium has been added, the material selected from one or more of zeolites, cation-exchangeable clay minerals, fly ash, mesostructured materials, activated carbons, cellulose acetate, and like porous and/or fibrous materials; and contacting the aqueous medium with the material to which zirconium has been added. The invention operates on all arsenic species in the form of arsenate, arsenite and organometallic arsenic, with no pretreatment necessary (e.g., oxidative conversion of arsenite to arsenate).

  19. Normal Zirconium Isotopic Composition in Murchison Hibonite 13-13

    NASA Astrophysics Data System (ADS)

    Ireland, T. R.

    1993-07-01

    Murchison hibonite 13-13 has a special place in isotopic astronomy because it has the largest isotopic anomalies in Ca and Ti as yet measured with delta ^48Ca at +105 per mil and delta ^50Ti at +273 per mil [1]. It has been suggested that these anomalies are the result of nucleosynthesis in neutron-rich supernova ejecta [2] and Ca and Ti in this hibonite grain have been the least diluted by normal solar system material. It would be expected that the isotopic compositions of the other Fe peak elements would also show the effects of the same nucleosynthetic process(es), but the abundances of the other elements are quite low. This is because of the refractory composition of hibonite and the relatively high volatilities of the other Fe peak elements. Zirconium is another refractory element that has recently been examined for its isotopic composition. Harper and coworkers [3] found a small ^96Zr enhancement (~2 epsilon) in Allende CAIs, and it was suggested that the ^96Zr anomaly was correlated with the ^50Ti enhancements (~10 epsilon) in the same inclusions and that both isotopes were produced by the same process [4]. The purpose of this report is to test whether a ^96Zr anomaly can be resolved in 13-13. If present at the same level as in the Allende CAIs relative to the ^50Ti anomaly, a ^96Zr enhancement of the order of 60 per mil should be observed. Zirconium isotopic compositions were measured by ion microprobe mass spectrometry. A mass resolution of 8000 (1% valley) was found to be sufficient to resolve molecular interferences as well as hydrides. However, in some hibonite analyses, tailing from ^40Ca(sub)2^160^+ became unacceptably large. Terrestrial zircon and Zr metal standards were also measured, and good agreement was found with terrestrial Zr isotopic compositions [5] after normalization to the ^94Zr/^90Zr ratio. The Zr isotopic composition of 13-13 is normal within expenmental uncertainty and the maximum anomaly at the 2- sigma level is well below 10 per mil (Fig. 1). No ^96Zr anomaly is associated with the large ^50Ti anomaly in this Murchison hibonite, and so it is unlikely that the nucleosynthetic model of Harper and coworkers for coproduction of ^96Zr and ^50Ti is valid. References: [1] Ireland T. R. (1990) GCA, 54, 3219-3237. [2] Hartmann D. et al.(1985) Astrophys. J., 297, 837-845. [3] Harper C. L. et al. (1990) Meteoritics, 25, 369. [4] Harper C. L. et al. (1991) LPSC XXII, 517-518. [5] Minster J. and Ricard L. P. (1981) Int. J. Mass Spec. Ion Phys., 37, 259-272. Fig. 1 appears in the hard copy here.

  20. Ultrasonic texture characterization of aluminum, zirconium and titanium alloys

    SciTech Connect

    Anderson, A.J.

    1997-10-08

    This work attempts to show the feasibility of nondestructive characterization of non-ferrous alloys. Aluminum alloys have a small single crystal anisotropy which requires very precise ultrasonic velocity measurements for derivation of orientation distribution coefficients (ODCs); the precision in the ultrasonic velocity measurement required for aluminum alloys is much greater than is necessary for iron alloys or other alloys with a large single crystal anisotropy. To provide greater precision, some signal processing corrections need to be applied to account for the inherent, half-bandwidth offset in triggered pulses when using a zero-crossing technique for determining ultrasonic velocity. In addition, alloys with small single crystal anisotropy show a larger dependence on the single crystal elastic constants (SCECs) when predicting ODCs which require absolute velocity measurements. Attempts were made to independently determine these elastics constants in an effort to improve correlation between ultrasonically derived ODCs and diffraction derived ODCs. The greater precision required to accurately derive ODCs in aluminum alloys using ultrasonic nondestructive techniques is easily attainable. Ultrasonically derived ODCs show good correlation with derivations made by Bragg diffraction techniques, both neutron and X-ray. The best correlation was shown when relative velocity measurements could be used in the derivations of the ODCs. Calculation of ODCs in materials with hexagonal crystallites can also be done. Because of the crystallite symmetries, more information can be extracted using ultrasonic techniques, but at a cost of requiring more physical measurements. Some industries which use materials with hexagonal crystallites, e.g. zirconium alloys and titanium, have traditionally used texture parameters which provide some specialized measure of the texture. These texture parameters, called Kearns factors, can be directly related to ODCs.

  1. Mechanical behaviour of excimer laser irradiated polycrystalline zirconium

    NASA Astrophysics Data System (ADS)

    Jelani, Mohsan; Bashir, Shazia; Akram, Mahreen; Yousaf, Daniel; Afzal, Naveed; Ahmad, Sajjad

    2014-02-01

    The effects of laser irradiation on the mechanical response of polycrystalline zirconium (Zr) have been investigated. Zr samples were irradiated with an excimer (KrF) laser (? ? 248 nm, ? ? 18 ns and repetition rate ?30 Hz). The irradiation was performed in the ambient environment of a gas mixture containing (CO2:N2:He) under a filling pressure of 20 Torr by varying laser fluences ranging from 3.8 to 5.1 J cm-2. The surface and structural modification of the irradiated targets were investigated using a scanning electron microscope (SEM) and x-ray diffractometer (XRD). In order to explore the mechanical properties of the irradiated Zr, the tensile testing and Vickers microhardness testing techniques were employed. SEM analysis reveals the grain growth on the irradiated Zr surfaces; however, for increasing fluence up to 4.7 J cm-2, the appearance of the grains becomes more distinct with an increase in their number density and decrease in size. For the maximum fluence of 5.1 J cm-2, the grains completely vanish and the surface becomes diffusive. XRD analysis reveals the appearance of new phases of ZrN and ZrO2. The variation in the peak intensity is observed to be anomalous, whereas the decreasing trend in the crystallite size and residual stresses is observed with increasing fluence. The microhardness analysis reveals the increasing trend in surface hardness with increasing fluence. The tensile testing demonstrates the anomalous behaviour of the yield stress and ultimate tensile strength with increasing fluence.

  2. /sup 97/Ru-DMSA for delayed renal imaging. [Dogs

    SciTech Connect

    Oster, Z.H.; Som, P.; Gil, M.C.; Goldman, A.G.; Fairchild, R.G.; Meinken, G.E.; Srivastava, S.C.; Atkins, H.L.; Richards, P.; Brill, A.B.

    1981-01-01

    Dimercaptosuccinic acid (DMSA) was labeled with /sup 97/Ru both with and without the addition of SnCl.2H/sub 2/O. The tin-containing preparation was found to induce higher cortical deposition of /sup 97/Ru-DMSA than the tin-free preparation. Visualization of the renal cortex was excellent 4 to 48 hours after injection in normal dogs with renal insufficiency. It is concluded that /sup 97/Ru-(Sn+/sup 2/)-DMSA is a potentially useful renal imaging agent when delayed scintigraphy is necessary because of decompensaton of the kidneys.

  3. /sup 97/Ru-DMSA for delayed renal imaging

    SciTech Connect

    Oster, Z.H. (State Univ. of New York, Stony Brook); Som, P.; Gil, M.C.

    1981-10-01

    Dimercaptosuccinic acid (DMSA) was labeled with /sup 97/Ru both with and without the addition of SnCl-2H/sub 2/O. The tin-containing preparation was found to induce higher cortical deposition of /sup 97/Ru-DMSA than the tin-free preparation. Visualization of the renal cortex was excellent 4 to 48 hours after injection in normal dogs and in dogs with renal insufficiency. It is concluded that /sup 97/Ru-(SN/sup 2 +/)-DMSA is a potentially useful renal imaging agent when delayed scintigraphy is necessary because of decompensation of the kidneys.

  4. Models for Three-Dimensional Tables > data97Logistic <-read.table(file="Table9.7Logistic.txt",header=T)

    E-print Network

    Langseth, Helge

    .7Logistic.txt",header=T) > data97Logistic data97Logistic case ulcer nonasp ulcer + case*ulcer, family=binomial, data=data97Logistic) > summary(M1) Call: glm(formula = cbind(nonasp, asp) ~ case + ulcer + case * ulcer, family = binomial, data = data97

  5. 44 CFR 9.7 - Determination of proposed action's location.

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ...FLOODPLAIN MANAGEMENT AND PROTECTION OF WETLANDS § 9.7 Determination of proposed...involves a critical action), or (2) a wetland. (b) Information needed. The...the Orders to (1) avoid floodplain and wetland locations unless they are the only...

  6. 44 CFR 9.7 - Determination of proposed action's location.

    Code of Federal Regulations, 2012 CFR

    2012-10-01

    ...FLOODPLAIN MANAGEMENT AND PROTECTION OF WETLANDS § 9.7 Determination of proposed...involves a critical action), or (2) a wetland. (b) Information needed. The...the Orders to (1) avoid floodplain and wetland locations unless they are the only...

  7. 44 CFR 9.7 - Determination of proposed action's location.

    Code of Federal Regulations, 2011 CFR

    2011-10-01

    ...FLOODPLAIN MANAGEMENT AND PROTECTION OF WETLANDS § 9.7 Determination of proposed...involves a critical action), or (2) a wetland. (b) Information needed. The...the Orders to (1) avoid floodplain and wetland locations unless they are the only...

  8. 44 CFR 9.7 - Determination of proposed action's location.

    Code of Federal Regulations, 2014 CFR

    2014-10-01

    ...FLOODPLAIN MANAGEMENT AND PROTECTION OF WETLANDS § 9.7 Determination of proposed...involves a critical action), or (2) a wetland. (b) Information needed. The...the Orders to (1) avoid floodplain and wetland locations unless they are the only...

  9. 44 CFR 9.7 - Determination of proposed action's location.

    Code of Federal Regulations, 2013 CFR

    2013-10-01

    ...FLOODPLAIN MANAGEMENT AND PROTECTION OF WETLANDS § 9.7 Determination of proposed...involves a critical action), or (2) a wetland. (b) Information needed. The...the Orders to (1) avoid floodplain and wetland locations unless they are the only...

  10. 7 CFR 97.16 - Amendment by applicant.

    Code of Federal Regulations, 2012 CFR

    2012-01-01

    An application may be amended before or after the first examination and action by the Office, after the second or subsequent examination or reconsideration as specified in § 97.107, or when and as specifically required by the...

  11. 97. VIEW OF MILL SOLUTION PUMP No. 2 FROM SOUTHEAST. ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    97. VIEW OF MILL SOLUTION PUMP No. 2 FROM SOUTHEAST. SUMPS ARE UNDER FLOOR, BEYOND. STAIR LEADS TO AGITATOR/GOLD TANK ACCESS PLATFORM. - Bald Mountain Gold Mill, Nevada Gulch at head of False Bottom Creek, Lead, Lawrence County, SD

  12. 40 CFR 97.351 - Establishment of accounts.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ...NOX AND SO2 TRADING PROGRAMS CAIR NOX Ozone Season Allowance Tracking System § 97...a compliance account for the CAIR NOX Ozone Season source for which the certificate...purpose of holding and transferring CAIR NOX Ozone Season allowances. An...

  13. 40 CFR 97.313 - Certificate of representation.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... CAIR Designated Representative for CAIR NOX Ozone Season Sources § 97.313 Certificate of...Administrator: (1) Identification of the CAIR NOX Ozone Season source, and each CAIR NOX Ozone Season unit at the source, for which the...

  14. 97. George Newman Photographer. VIEW OF SOUTH END OF THE ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    97. George Newman Photographer. VIEW OF SOUTH END OF THE NEBRASKA SWING SPAN SHOWING THE BRIDGE OPEN APRIL 13, 1945. - Pacific Shortline Bridge, U.S. Route 20,spanning Missouri River, Sioux City, Woodbury County, IA

  15. p97, a protein coping with multiple identities.

    PubMed

    Woodman, Philip G

    2003-11-01

    A topic that is keeping cell biologists across several fields occupied is how the AAA ATPase p97 can have so many apparently unrelated functions. A recent model that proposed sets of adaptors for p97 selected according to the type of p97 activity seemed to afford a simple solution. For example, one known adaptor, the Ufd1-Npl4 complex, has been implicated in ubiquitin-dependent proteolysis whereas another, p47, is an essential co-factor for membrane fusion. However, further investigation has revealed that the situation is more complicated. Both Ufd1-Npl4 and p47 adaptors bind ubiquitin, and so their activities may be more closely related than first thought. A role for ubiquitin in p97-dependent membrane fusion is a particularly surprising development with no obvious explanation. However, some clues may be found from looking at the role of ubiquitin and the AAA ATPase Vps4 during sorting on the endocytic pathway. PMID:14514884

  16. 40 CFR 98.97 - Records that must be retained.

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ...Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) AIR PROGRAMS (CONTINUED) MANDATORY GREENHOUSE GAS REPORTING Electronics Manufacturing § 98.97 Records that must be retained. In addition to the information required by §...

  17. 40 CFR 98.97 - Records that must be retained.

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ...Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) AIR PROGRAMS (CONTINUED) MANDATORY GREENHOUSE GAS REPORTING Electronics Manufacturing § 98.97 Records that must be retained. In addition to the information required by §...

  18. MISSION CONTROL CENTER STATUS REPORT #1 STS-97

    NSDL National Science Digital Library

    2000-01-01

    On Sunday November 30, STS-97 Mission Specialists Carlos Noriega and Joe Tanner began the eleventh space walk in the history of the International Space Station. A daily status report on this mission is available from NASA's Johnson Space Center.

  19. 40 CFR 97.351 - Establishment of accounts.

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ...SO2 TRADING PROGRAMS CAIR NOX Ozone Season Allowance Tracking System § 97.351...compliance account for the CAIR NOX Ozone Season source for which the certificate of...holding and transferring CAIR NOX Ozone Season allowances. An application...

  20. 40 CFR 97.313 - Certificate of representation.

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ...Designated Representative for CAIR NOX Ozone Season Sources § 97.313 Certificate of representation...1) Identification of the CAIR NOX Ozone Season source, and each CAIR NOX Ozone Season unit at the source, for which the...

  1. 40 CFR 97.351 - Establishment of accounts.

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ...SO2 TRADING PROGRAMS CAIR NOX Ozone Season Allowance Tracking System § 97.351...compliance account for the CAIR NOX Ozone Season source for which the certificate of...holding and transferring CAIR NOX Ozone Season allowances. An application...

  2. 40 CFR 97.313 - Certificate of representation.

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ...Designated Representative for CAIR NOX Ozone Season Sources § 97.313 Certificate of representation...1) Identification of the CAIR NOX Ozone Season source, and each CAIR NOX Ozone Season unit at the source, for which the...

  3. 40 CFR 97.313 - Certificate of representation.

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ...Designated Representative for CAIR NOX Ozone Season Sources § 97.313 Certificate of representation...1) Identification of the CAIR NOX Ozone Season source, and each CAIR NOX Ozone Season unit at the source, for which the...

  4. 40 CFR 97.516 - Certificate of representation.

    Code of Federal Regulations, 2014 CFR

    2014-07-01

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  5. 40 CFR 97.351 - Establishment of accounts.

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ...SO2 TRADING PROGRAMS CAIR NOX Ozone Season Allowance Tracking System § 97.351...compliance account for the CAIR NOX Ozone Season source for which the certificate of...holding and transferring CAIR NOX Ozone Season allowances. An application...

  6. 12 CFR 238.97 - Change in circumstances.

    Code of Federal Regulations, 2013 CFR

    2013-01-01

    ...COMPANIES (REGULATION LL) Management Official Interlocks § 238.97 Change in circumstances. (a) Termination. A management official shall terminate his...or apply for an exemption if a change in circumstances causes...

  7. 12 CFR 238.97 - Change in circumstances.

    Code of Federal Regulations, 2012 CFR

    2012-01-01

    ...COMPANIES (REGULATION LL) Management Official Interlocks § 238.97 Change in circumstances. (a) Termination. A management official shall terminate his...or apply for an exemption if a change in circumstances causes...

  8. 12 CFR 238.97 - Change in circumstances.

    Code of Federal Regulations, 2014 CFR

    2014-01-01

    ...COMPANIES (REGULATION LL) Management Official Interlocks § 238.97 Change in circumstances. (a) Termination. A management official shall terminate his...or apply for an exemption if a change in circumstances causes...

  9. 7 CFR 97.190 - When open records are available.

    Code of Federal Regulations, 2011 CFR

    2011-01-01

    ... PLANT VARIETY AND PROTECTION Availability of Office Records § 97.190 When open records are available. Copies of records, which are open to the public and in the custody of the Office, may be examined in the Office during...

  10. 7 CFR 97.190 - When open records are available.

    Code of Federal Regulations, 2010 CFR

    2010-01-01

    ... PLANT VARIETY AND PROTECTION Availability of Office Records § 97.190 When open records are available. Copies of records, which are open to the public and in the custody of the Office, may be examined in the Office during...

  11. 47 CFR 97.407 - Radio amateur civil emergency service.

    Code of Federal Regulations, 2012 CFR

    2012-10-01

    ...Telecommunication 5 2012-10-01 2012-10-01 false Radio amateur civil emergency service. 97.407 Section...COMMUNICATIONS COMMISSION (CONTINUED) SAFETY AND SPECIAL RADIO SERVICES AMATEUR RADIO SERVICE Providing Emergency Communications...

  12. 47 CFR 97.407 - Radio amateur civil emergency service.

    Code of Federal Regulations, 2013 CFR

    2013-10-01

    ...Telecommunication 5 2013-10-01 2013-10-01 false Radio amateur civil emergency service. 97.407 Section...COMMUNICATIONS COMMISSION (CONTINUED) SAFETY AND SPECIAL RADIO SERVICES AMATEUR RADIO SERVICE Providing Emergency Communications...

  13. 47 CFR 97.407 - Radio amateur civil emergency service.

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ...Telecommunication 5 2010-10-01 2010-10-01 false Radio amateur civil emergency service. 97.407 Section...COMMUNICATIONS COMMISSION (CONTINUED) SAFETY AND SPECIAL RADIO SERVICES AMATEUR RADIO SERVICE Providing Emergency Communications...

  14. 47 CFR 97.407 - Radio amateur civil emergency service.

    Code of Federal Regulations, 2011 CFR

    2011-10-01

    ...Telecommunication 5 2011-10-01 2011-10-01 false Radio amateur civil emergency service. 97.407 Section...COMMUNICATIONS COMMISSION (CONTINUED) SAFETY AND SPECIAL RADIO SERVICES AMATEUR RADIO SERVICE Providing Emergency Communications...

  15. 40 CFR 97.313 - Certificate of representation.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... CAIR Designated Representative for CAIR NOX Ozone Season Sources § 97.313 Certificate of...Administrator: (1) Identification of the CAIR NOX Ozone Season source, and each CAIR NOX Ozone Season unit at the source, for which the...

  16. 40 CFR 97.351 - Establishment of accounts.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ...NOX AND SO2 TRADING PROGRAMS CAIR NOX Ozone Season Allowance Tracking System § 97...a compliance account for the CAIR NOX Ozone Season source for which the certificate...purpose of holding and transferring CAIR NOX Ozone Season allowances. An...

  17. 7 CFR 97.175 - Fees and charges.

    Code of Federal Regulations, 2011 CFR

    2011-01-01

    ...and Charges § 97.175 Fees and charges. The following fees and charges apply to the services and actions specified...exceed $107.00 per employee-hour. Charges also will be made for materials, space, and administrative costs....

  18. 7 CFR 97.175 - Fees and charges.

    Code of Federal Regulations, 2014 CFR

    2014-01-01

    ...and Charges § 97.175 Fees and charges. The following fees and charges apply to the services and actions specified...exceed $107.00 per employee-hour. Charges also will be made for materials, space, and administrative costs....

  19. 7 CFR 97.175 - Fees and charges.

    Code of Federal Regulations, 2010 CFR

    2010-01-01

    ...and Charges § 97.175 Fees and charges. The following fees and charges apply to the services and actions specified...exceed $107.00 per employee-hour. Charges also will be made for materials, space, and administrative costs....

  20. 7 CFR 97.175 - Fees and charges.

    Code of Federal Regulations, 2012 CFR

    2012-01-01

    ...and Charges § 97.175 Fees and charges. The following fees and charges apply to the services and actions specified...exceed $107.00 per employee-hour. Charges also will be made for materials, space, and administrative costs....

  1. 7 CFR 97.175 - Fees and charges.

    Code of Federal Regulations, 2013 CFR

    2013-01-01

    ...and Charges § 97.175 Fees and charges. The following fees and charges apply to the services and actions specified...exceed $107.00 per employee-hour. Charges also will be made for materials, space, and administrative costs....

  2. 46 CFR 97.15-55 - Requirements for fuel oil.

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ...Shipping COAST GUARD, DEPARTMENT OF HOMELAND SECURITY (CONTINUED) CARGO AND MISCELLANEOUS VESSELS OPERATIONS Tests, Drills, and Inspections § 97.15-55 Requirements for fuel oil. (a) It shall be the duty of the chief engineer...

  3. Enhanced surveillance program FY97 accomplishments. Progress report

    SciTech Connect

    Mauzy, A. [ed.; Laake, B. [comp.

    1997-10-01

    This annual report is one volume of the Enhanced Surveillance Program (ESP) FY97 Accomplishments. The complete accomplishments report consists of 11 volumes. Volume 1 includes an ESP overview and a summary of selected unclassified FY97 program highlights. Volume 1 specifically targets a general audience, reflecting about half of the tasks conducted in FY97 and emphasizing key program accomplishments and contributions. The remaining volumes of the accomplishments report are classified, organized by program focus area, and present in technical detail the progress achieved in each of the 104 FY97 program tasks. Focus areas are as follows: pits; high explosives; organics; dynamics; diagnostics; systems; secondaries; nonnuclear materials; nonnuclear components; and Surveillance Test Program upgrades.

  4. 19 CFR 12.97 - Importations contrary to law.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ...SECURITY; DEPARTMENT OF THE TREASURY SPECIAL CLASSES OF MERCHANDISE Switchblade Knives § 12.97 Importations contrary to law. Importations of switchblade knives, except as permitted by 15 U.S.C. 1244, are importations contrary...

  5. 97. DETAIL OF FOURTH CATWALK LEVEL SHOWING WEST SIDE, LOOKING ...

    Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

    97. DETAIL OF FOURTH CATWALK LEVEL SHOWING WEST SIDE, LOOKING NORTH, INNER DOME ON RIGHT WITH KNEE BRACE FROM INNER COLUMN TO CROSS BEAM - Maryland State House, State Circle, Annapolis, Anne Arundel County, MD

  6. ANNUAL REVIEW 1996 -97 Department of Information Science

    E-print Network

    Imai, Hiroshi

    ANNUAL REVIEW 1996 - 97 Department of Information Science Faculty of Science : : : : : : : : : : : : : : : : : : : : : : * *: : : : : : : : 1 1.1.3 Publications and Research Papers in 1996-1997 : : : : : : : : : * *: : : : : 4 1.2.2 Publications and Research Papers in 1996-1997 : : : : : : : : : * *: : : : : 10 1

  7. 28 CFR 0.97 - Redelegation of authority.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ...THE DEPARTMENT OF JUSTICE Bureau of Prisons § 0.97 Redelegation of authority. The Director of the Bureau of Prisons is authorized to redelegate...redelegations by the Director of the Bureau of Prisons shall continue in force and...

  8. 28 CFR 0.97 - Redelegation of authority.

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ...THE DEPARTMENT OF JUSTICE Bureau of Prisons § 0.97 Redelegation of authority. The Director of the Bureau of Prisons is authorized to redelegate...redelegations by the Director of the Bureau of Prisons shall continue in force and...

  9. 28 CFR 0.97 - Redelegation of authority.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ...THE DEPARTMENT OF JUSTICE Bureau of Prisons § 0.97 Redelegation of authority. The Director of the Bureau of Prisons is authorized to redelegate...redelegations by the Director of the Bureau of Prisons shall continue in force and...

  10. 28 CFR 0.97 - Redelegation of authority.

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ...THE DEPARTMENT OF JUSTICE Bureau of Prisons § 0.97 Redelegation of authority. The Director of the Bureau of Prisons is authorized to redelegate...redelegations by the Director of the Bureau of Prisons shall continue in force and...

  11. Method for making fine and ultrafine spherical particles of zirconium titanate and other mixed metal oxide systems

    DOEpatents

    Hu, Michael Z.

    2006-05-23

    Disclosed is a method for making amorphous spherical particles of zirconium titanate and crystalline spherical particles of zirconium titanate comprising the steps of mixing an aqueous solution of zirconium salt and an aqueous solution of titanium salt into a mixed solution having equal moles of zirconium and titanium and having a total salt concentration in the range from 0.01 M to about 0.5 M. A stearic dispersant and an organic solvent is added to the mixed salt solution, subjecting the zirconium salt and the titanium salt in the mixed solution to a coprecipitation reaction forming a solution containing amorphous spherical particles of zirconium titanate wherein the volume ratio of the organic solvent to aqueous part is in the range from 1 to 5. The solution of amorphous spherical particles is incubated in an oven at a temperature .ltoreq.100.degree. C. for a period of time .ltoreq.24 hours converting the amorphous particles to fine or ultrafine crystalline spherical particles of zirconium titanate.

  12. STS-97 and Expedition One Crews Pose for Onboard Photo

    NASA Technical Reports Server (NTRS)

    2000-01-01

    In this image, the five STS-97 crew members pose with the 3 members of the Expedition One crew onboard the International Space Station (ISS) for the first ever traditional onboard portrait taken in the Zvezda Service Module. On the front row, left to right, are astronauts Brent W. Jett, Jr., STS-97 commander; William M. Shepherd, Expedition One mission commander; and Joseph R. Tarner, STS-97 mission specialist. On the second row, from the left are Cosmonaut Sergei K. Krikalev, Expedition One flight engineer; astronaut Carlos I. Noriega, STS-97 mission specialist; cosmonaut Yuri P. Gidzenko, Expedition One Soyuz commander; and Michael J. Bloomfield, STS-97 pilot. Behind them is astronaut Marc Garneau, STS-97 mission specialist representing the Canadian Space Agency (CSA). The primary objective of the STS-97 mission was the delivery, assembly, and activation of the U.S. electrical power system onboard the International Space Station (ISS). The electrical power system, which is built into a 73-meter (240-foot) long solar array structure consists of solar arrays, radiators, batteries, and electronics. The entire 15.4-metric ton (17-ton) package is called the P6 Integrated Truss Segment, and is the heaviest and largest element yet delivered to the station aboard a space shuttle. The electrical system will eventually provide the power necessary for the first ISS crews to live and work in the U.S. segment. The STS-97 crew of five launched aboard the Space Shuttle Orbiter Endeavor on November 30, 2000 for an 11 day mission.

  13. 5/3/12 97-1 1/4www.phy.ornl.gov/divops/ESH/97-1.html

    E-print Network

    5/3/12 97-1 1/4www.phy.ornl.gov/divops/ESH/97-1.html . Physics Division ESH Bulletin 97-1 X.phy.ornl.gov/divops/ESH/97-1.html exposure above their expected occupational dose. The operations manager conducted.phy.ornl.gov/divops/ESH/97-1.html have resulted in radiological contamination of occupied work spaces. Investigators

  14. Self-accommodation of crystals of martensitic phases in titanium and zirconium based alloys

    NASA Astrophysics Data System (ADS)

    Khundzhua, A. G.; Ptitsyn, A. G.; Brovkina, E. A.; Chzhen, S.

    2012-11-01

    The orientation relationships between austenite and ?' and ?? martensite lattices in titanium and zirconium alloys is performed in view of the possibility of the formation of self-accommodating complexes, which is an important component of the shape memory effect. Different diffraction patterns calculated for various matrices of the orientation relationship were compared with the experimental patterns for Ti45Zr45Nb10 alloy using a formula developed for the optimal expression of the orientation relationship for ??. The generalization and analysis of the literature data for titanium- and zirconium-based solid solutions performed using the developed algorithm lead us to conclusions regarding the tendency of ?' martensite in titanium-based solid solutions to self-accommodate, which occurred more strongly than that in zirconium-based alloys, and the best results in shape memory realization should be expected in Ti-Ta and Ti-Nb systems. Possible reasons for the absence of the shape memory effect for ?' martensite in titanium- and zirconium-based alloys, with regard to the necessary crystallographic conditions for the formation of self-accommodating processes are analyzed.

  15. PHASE AND EQUILIBRIUM PRESSURE STUDIES OF THE ZIRCONIUM-TITANIUM-HYDROGEN SYSTEM

    Microsoft Academic Search

    V. Y. Labaton; E. V. Garner; E. Whitehead

    1962-01-01

    Equilibrium pressure curves were determined for the ternary zirconium -; titanium - hydrogen system, based on the 55 atomic per cent alloy, between 550 ; and 650 deg C, and a tentative phase diagram was constructed for the addition of ; hydrogen to the alloy. A room-temperature x-ray study identified the expected ; phases in the ternary system isomorphous with

  16. Spectroscopic investigation of direct current (DC) plasma electrolytic oxidation of zirconium in citric acid.

    PubMed

    Stojadinovi?, Stevan; Radi?-Peri?, Jelena; Vasili?, Rastko; Peri?, Miljenko

    2014-01-01

    Plasma electrolytic oxidation of zirconium in citric acid was investigated using optical spectroscopy. A rich emission spectrum consisting of about 360 zirconium and 170 oxygen atomic and ionic lines was identified in the spectral regions 313-320, 340-516, and 626-640 nm. It was shown that the remaining features observed in the spectrum could be ascribed to various molecular species, which involve zirconium, oxygen, hydrogen, and carbon. The temperature of the plasma core (T = 7500 ± 1000 K) was determined using measured Zr line intensities, and the temperature of peripheral plasma zone (T = 2800 ± 500 K) was estimated from the intensity distribution within a part of an OH spectrum. The composition of the plasma containing zirconium, oxygen, and hydrogen, under assumption of local thermal equilibrium, was calculated in the temperature range up to 12,000 K and for pressure of 10(5) and 10(7) Pa, in order to explain the appearance of the observed spectral features. PMID:24405960

  17. Evaluation of zirconium-iron-rhenium alloys as surrogates for a technetium alloy waste form

    E-print Network

    Mews, Paul Aaron

    2009-05-15

    , 2) an FeZr 2-type intermetallic with 11 wt % or less Re, and 3) a second intermetallic with about 18 wt % Re. Zirconium rich samples formed as many as five distinct phases: 1) a Zr solid solution phase, 2) a Zr3Fe-type intermetallic with as much as 13...

  18. Zirconium, Niobium, Antimony, Vanadium and Lead in Rats: Life term studies

    Microsoft Academic Search

    HENRY A. SCHROEDER; MARIAN MITCHENER

    To evaluate innate effects of the trace elements zirconium, niobium, antimony and vanadium, and to reevaluate those of lead, 603 rats of the Long-Evans strain were fed a diet containing relatively small amounts of these elements in an environment reasonably free of trace contaminants. Groups of 100 or more divided as to sex were given 5 ppm (as metal) either

  19. Comparison of the ion-exchange behaviour of zirconium, thorium, vanadium, uranium, stannic and titanium tungstates.

    PubMed

    Qureshi, M; Gupta, J P; Sharma, V

    1974-01-01

    Zirconium, thorium, uranium, vanadium, stannic and titanium tungstates have been prepared and their properties such as ion-exchange capacity, K(d) values of metal ions, chemical composition and stability have been compared. Titanium tungstate was found to be the most stable, and to have negligible capacity for tervalent cations. PMID:18961426

  20. Recycle of Zirconium from Used Nuclear Fuel Cladding: A Major Element of Waste Reduction

    Microsoft Academic Search

    Emory D Collins; Guillermo D DelCul; N. V. Emmanuel

    2011-01-01

    Feasibility tests were initiated to determine if the zirconium in commercial used nuclear fuel (UNF) cladding can be recovered in sufficient purity to permit re-use, and if the recovery process can be operated economically. Initial tests are being performed with unirradiated, non-radioactive samples of various types of Zircaloy materials that are used in UNF cladding to develop the recovery process

  1. Quasi-Differential Neutron Scattering in Zirconium from 0.5 to 20 MeV

    E-print Network

    Danon, Yaron

    Quasi-Differential Neutron Scattering in Zirconium from 0.5 to 20 MeV D. P. Barry,* G. Leinweber, R-3590 Received January 10, 2012 Accepted August 10, 2012 Abstract ­ High-energy-neutron-scattering experiments,V' r V! ~Ref. 1!. This term represents the contribution from neutrons scatter- ing from energy E

  2. Zirconium-doped tantalum oxide high-k gate dielectric films

    E-print Network

    Tewg, Jun-Yen

    2005-02-17

    A new high-k dielectric material, i.e., zirconium-doped tantalum oxide (Zr-doped TaOx), in the form of a sputter-deposited thin film with a thickness range of 5-100 nm, has been studied. Important applications of this new dielectric material include...

  3. Laboratory production of zirconium carbide compacts for use in inert matrix fuels

    NASA Astrophysics Data System (ADS)

    Vasudevamurthy, Gokul; Knight, Travis W.; Roberts, Elwyn; Adams, Thad M.

    2008-02-01

    Zirconium carbide is being actively considered for use as an inert matrix material in composite nuclear fuel for gas-cooled fast reactors. ZrC can be produced either by the endothermic carbothermal reduction of zirconium dioxide or by the direct exothermic reaction of pure zirconium and graphite powder mixtures. The exothermic reaction is classified as combustion synthesis or self heating synthesis. Experiments were conducted to demonstrate the combustion synthesis reaction of zirconium and graphite powders and measure the ignition and adiabatic temperatures. The heat released during this short reaction time was sufficient only to partially sinter the compacts to less than 40% theoretical density. Subsequently, compacts of ZrC were similarly produced by combustion synthesis followed by a short, high temperature hold at 2440 °C to relieve residual stresses in the compacts following the rapid reaction sintering. External pressures of up to 5.2 MPa were used as an additional driving force for sintering. The effects of reactant particle size and degree of uniaxial pressing on the product density and porosity were also studied. Higher densities in the fabricated compacts were noted for higher uniaxial pressures irrespective of powder size. Also, smaller powder sizes produced compacts up to 92% TD, while larger particle sizes produced compacts up to 84% TD for the same pressure. The compacts were characterized based on composition, microstructure, and density/porosity. Results of the different experiments are presented.

  4. Peculiarities of the formation of intermetallic coatings based on platinum and zirconium

    NASA Astrophysics Data System (ADS)

    Bystrov, Yu. A.; Vetrov, N. Z.; Lisenkov, A. A.

    2014-12-01

    We have studied the relationship between the method of production and properties of a multicomponent antiemission coating. A method of obtaining a complex coating with the formation of intermetallic compounds based on platinum and zirconium is proposed. A technology of Pt3Zr intermetallide synthesis that ensures the formation of a uniform coating with stable composition is developed.

  5. Recycle of Zirconium from Used Nuclear Fuel Cladding: A Major Element of Waste Reduction

    SciTech Connect

    Collins, Emory D [ORNL; DelCul, Guillermo D [ORNL; Terekhov, Dmitri [ORNL; Emmanuel, N. V. [Chemical Vapor Metal Refining, Inc.

    2011-01-01

    Feasibility tests were initiated to determine if the zirconium in commercial used nuclear fuel (UNF) cladding can be recovered in sufficient purity to permit re-use, and if the recovery process can be operated economically. Initial tests are being performed with unirradiated, non-radioactive samples of various types of Zircaloy materials that are used in UNF cladding to develop the recovery process and determine the degree of purification that can be obtained. Early results indicate that quantitative recovery can be accomplished and product contamination with alloy constituents can be controlled sufficiently to meet purification requirements. Future tests with actual radioactive UNF cladding are planned. The objective of current research is to determine the feasibility of recovery and recycle of zirconium from used fuel cladding wastes. Zircaloy cladding, which contains 98+% of hafnium-free zirconium, is the second largest mass, on average {approx}25 wt %, of the components in used U.S. light-water-reactor fuel assemblies. Therefore, recovery and recycle of the zirconium would enable a large reduction in geologic waste disposal for advanced fuel cycles. Current practice is to compact or grout the cladding waste and store it for subsequent disposal in a geologic repository. This paper describes results of initial tests being performed with unirradiated, non-radioactive samples of various types of Zircaloy materials that are used in UNF cladding to develop the recovery process and determine the degree of purification that can be obtained. Future tests with actual radioactive UNF cladding are planned.

  6. Investigation on Thermal Analysis of Binary Zirconium\\/Oxidant Pyrotechnic Systems

    Microsoft Academic Search

    S. M. Pourmortazavi; S. G. Hosseini; S. S. Hajimirsadeghi; R. Fareghi Alamdari

    2008-01-01

    Thermogravimetric analysis (TGA) and differential thermal analysis (DTA) have been used to examine the thermal behavior of powdered zirconium with some pyrotechnic oxidants, in relation to the behavior of the individual constituents. The results showed that decomposition temperature for pure compounds (potassium nitrate, potassium chlorate, potassium perchlorate, barium nitrate and barium peroxide) are 540, 472, 592, 745 and 600°C, respectively.

  7. Giant magnetoelectric effect in Nilead zirconium titanate cylindrical D. A. Pan,1,a

    E-print Network

    Volinsky, Alex A.

    Giant magnetoelectric effect in Ni­lead zirconium titanate cylindrical structure D. A. Pan,1,a Y.10 To achieve better magnetoelectric properties, giant mag- netostrictive material Tb1-xDyxFe2-y binder. In this work, the giant ME effect under high applied magnetic field in bilayered Ni

  8. DETERMINATION OF OXYGEN IN ZIRCONIUM METAL BY VACUUM FUSION METHOD AND BROMINATION-CARBON REDUCTION METHOD

    Microsoft Academic Search

    Otake

    1958-01-01

    Determination of oxygen in zirconium metal was studied by the vacuum ; fusion method and the bromination-carbon reduction method. In the vacuum fusion ; method, the iron-tin bath technique usually applied for the analysis of gases in ; titanium metal was used. In this case the molten iron bath in a graphite ; crucible is the reaction medium. The sample

  9. 15 CFR 9.7 - Department of Commerce energy conservation mark.

    Code of Federal Regulations, 2011 CFR

    2011-01-01

    ...false Department of Commerce energy conservation mark. 9.7 Section 9.7 Commerce...APPLIANCES AND EQUIPMENT TO EFFECT ENERGY CONSERVATION § 9.7 Department of Commerce energy conservation mark. The Department of...

  10. 15 CFR 9.7 - Department of Commerce energy conservation mark.

    Code of Federal Regulations, 2010 CFR

    2010-01-01

    ...false Department of Commerce energy conservation mark. 9.7 Section 9.7 Commerce...APPLIANCES AND EQUIPMENT TO EFFECT ENERGY CONSERVATION § 9.7 Department of Commerce energy conservation mark. The Department of...

  11. 15 CFR 9.7 - Department of Commerce energy conservation mark.

    Code of Federal Regulations, 2013 CFR

    2013-01-01

    ...false Department of Commerce energy conservation mark. 9.7 Section 9.7 Commerce...APPLIANCES AND EQUIPMENT TO EFFECT ENERGY CONSERVATION § 9.7 Department of Commerce energy conservation mark. The Department of...

  12. 15 CFR 9.7 - Department of Commerce energy conservation mark.

    Code of Federal Regulations, 2014 CFR

    2014-01-01

    ...false Department of Commerce energy conservation mark. 9.7 Section 9.7 Commerce...APPLIANCES AND EQUIPMENT TO EFFECT ENERGY CONSERVATION § 9.7 Department of Commerce energy conservation mark. The Department of...

  13. 15 CFR 9.7 - Department of Commerce energy conservation mark.

    Code of Federal Regulations, 2012 CFR

    2012-01-01

    ...false Department of Commerce energy conservation mark. 9.7 Section 9.7 Commerce...APPLIANCES AND EQUIPMENT TO EFFECT ENERGY CONSERVATION § 9.7 Department of Commerce energy conservation mark. The Department of...

  14. 34 CFR 97.111 - Criteria for IRB approval of research.

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... false Criteria for IRB approval of research. 97.111 Section 97.111 Education...Basic ED Policy for Protection of Human Research Subjects) § 97.111 Criteria for IRB approval of research. (a) In order to approve...

  15. 34 CFR 97.111 - Criteria for IRB approval of research.

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... false Criteria for IRB approval of research. 97.111 Section 97.111 Education...Basic ED Policy for Protection of Human Research Subjects) § 97.111 Criteria for IRB approval of research. (a) In order to approve...

  16. 34 CFR 97.111 - Criteria for IRB approval of research.

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... false Criteria for IRB approval of research. 97.111 Section 97.111 Education...Basic ED Policy for Protection of Human Research Subjects) § 97.111 Criteria for IRB approval of research. (a) In order to approve...

  17. 34 CFR 97.111 - Criteria for IRB approval of research.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... false Criteria for IRB approval of research. 97.111 Section 97.111 Education...Basic ED Policy for Protection of Human Research Subjects) § 97.111 Criteria for IRB approval of research. (a) In order to approve...

  18. 46 CFR 97.15-35 - Emergency training, musters, and drills.

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ... Emergency training, musters, and drills. 97.15-35 Section 97.15-35...MISCELLANEOUS VESSELS OPERATIONS Tests, Drills, and Inspections § 97.15-35 Emergency training, musters, and drills. Onboard training, musters,...

  19. 46 CFR 97.37-5 - General alarm bell contact maker.

    Code of Federal Regulations, 2011 CFR

    2011-10-01

    ...2011-10-01 false General alarm bell contact maker. 97.37-5 Section 97.37-5 Shipping... § 97.37-5 General alarm bell contact maker. Each general alarm contact maker must be marked in accordance with...

  20. 46 CFR 97.37-5 - General alarm bell contact maker.

    Code of Federal Regulations, 2012 CFR

    2012-10-01

    ...2012-10-01 false General alarm bell contact maker. 97.37-5 Section 97.37-5 Shipping... § 97.37-5 General alarm bell contact maker. Each general alarm contact maker must be marked in accordance with...

  1. 46 CFR 97.37-5 - General alarm bell contact maker.

    Code of Federal Regulations, 2013 CFR

    2013-10-01

    ...2013-10-01 false General alarm bell contact maker. 97.37-5 Section 97.37-5 Shipping... § 97.37-5 General alarm bell contact maker. Each general alarm contact maker must be marked in accordance with...

  2. 46 CFR 97.37-5 - General alarm bell contact maker.

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ...2010-10-01 false General alarm bell contact maker. 97.37-5 Section 97.37-5 Shipping... § 97.37-5 General alarm bell contact maker. Each general alarm contact maker must be marked in accordance with...

  3. 46 CFR 97.37-5 - General alarm bell contact maker.

    Code of Federal Regulations, 2014 CFR

    2014-10-01

    ...2014-10-01 false General alarm bell contact maker. 97.37-5 Section 97.37-5 Shipping... § 97.37-5 General alarm bell contact maker. Each general alarm contact maker must be marked in accordance with...

  4. 47 CFR 9.7 - Access to 911 and E911 service capabilities.

    Code of Federal Regulations, 2011 CFR

    2011-10-01

    ...capabilities. 9.7 Section 9.7 Telecommunication FEDERAL COMMUNICATIONS COMMISSION GENERAL INTERCONNECTED VOICE OVER INTERNET PROTOCOL SERVICES § 9.7 Access to 911 and E911 service capabilities. (a) Access. Subject to the other...

  5. 47 CFR 9.7 - Access to 911 and E911 service capabilities.

    Code of Federal Regulations, 2013 CFR

    2013-10-01

    ...capabilities. 9.7 Section 9.7 Telecommunication FEDERAL COMMUNICATIONS COMMISSION GENERAL INTERCONNECTED VOICE OVER INTERNET PROTOCOL SERVICES § 9.7 Access to 911 and E911 service capabilities. (a) Access. Subject to the other...

  6. 47 CFR 9.7 - Access to 911 and E911 service capabilities.

    Code of Federal Regulations, 2014 CFR

    2014-10-01

    ...capabilities. 9.7 Section 9.7 Telecommunication FEDERAL COMMUNICATIONS COMMISSION GENERAL INTERCONNECTED VOICE OVER INTERNET PROTOCOL SERVICES § 9.7 Access to 911 and E911 service capabilities. (a) Access. Subject to the other...

  7. 47 CFR 9.7 - Access to 911 and E911 service capabilities.

    Code of Federal Regulations, 2010 CFR

    2010-10-01

    ...capabilities. 9.7 Section 9.7 Telecommunication FEDERAL COMMUNICATIONS COMMISSION GENERAL INTERCONNECTED VOICE OVER INTERNET PROTOCOL SERVICES § 9.7 Access to 911 and E911 service capabilities. (a) Access. Subject to the other...

  8. 47 CFR 9.7 - Access to 911 and E911 service capabilities.

    Code of Federal Regulations, 2012 CFR

    2012-10-01

    ...capabilities. 9.7 Section 9.7 Telecommunication FEDERAL COMMUNICATIONS COMMISSION GENERAL INTERCONNECTED VOICE OVER INTERNET PROTOCOL SERVICES § 9.7 Access to 911 and E911 service capabilities. (a) Access. Subject to the other...

  9. 28 CFR 9.7 - Terms and conditions of remission and mitigation.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ...and mitigation. 9.7 Section 9.7 Judicial Administration DEPARTMENT OF JUSTICE REGULATIONS GOVERNING THE REMISSION OR MITIGATION OF CIVIL AND CRIMINAL FORFEITURES § 9.7 Terms and conditions of remission and mitigation....

  10. 28 CFR 9.7 - Terms and conditions of remission and mitigation.

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ...and mitigation. 9.7 Section 9.7 Judicial Administration DEPARTMENT OF JUSTICE REGULATIONS GOVERNING THE REMISSION OR MITIGATION OF CIVIL AND CRIMINAL FORFEITURES § 9.7 Terms and conditions of remission and mitigation....

  11. 28 CFR 9.7 - Terms and conditions of remission and mitigation.

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ...mitigation. 9.7 Section 9.7 Judicial Administration DEPARTMENT OF JUSTICE REGULATIONS GOVERNING THE REMISSION OR MITIGATION OF ADMINISTRATIVE, CIVIL, AND CRIMINAL FORFEITURES § 9.7 Terms and conditions of remission and...

  12. 28 CFR 9.7 - Terms and conditions of remission and mitigation.

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ...mitigation. 9.7 Section 9.7 Judicial Administration DEPARTMENT OF JUSTICE REGULATIONS GOVERNING THE REMISSION OR MITIGATION OF ADMINISTRATIVE, CIVIL, AND CRIMINAL FORFEITURES § 9.7 Terms and conditions of remission and...

  13. 28 CFR 9.7 - Terms and conditions of remission and mitigation.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ...and mitigation. 9.7 Section 9.7 Judicial Administration DEPARTMENT OF JUSTICE REGULATIONS GOVERNING THE REMISSION OR MITIGATION OF CIVIL AND CRIMINAL FORFEITURES § 9.7 Terms and conditions of remission and mitigation....

  14. 40 CFR 152.97 - Rights and obligations regarding the Data Submitters List.

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... false Rights and obligations regarding the Data Submitters List. 152.97 Section 152.97...AND CLASSIFICATION PROCEDURES Satisfaction of Data Requirements and Protection of Data Submitters' Rights § 152.97 Rights and...

  15. Carbothermal synthesis of ultra-fine zirconium carbide powders using inorganic precursors via sol–gel method

    Microsoft Academic Search

    Yongjie Yan; Zhengren Huang; Xuejian Liu; Dongliang Jiang

    2007-01-01

    Ultra-fine zirconium carbide (ZrC) powders have been synthesized by carbothermal reduction reactions using inorganic precursors\\u000a zirconium oxychloride (ZrOCl2 · 8H2O) as sources of zirconium and phenolic resin as the carbon source. The reactions were substantially completed at relatively\\u000a lower temperatures (?1400 °C\\/1 h) and the synthesized powders had a small average crystallite size (<200 nm) and a large specific\\u000a area (54 m2\\/g). The oxygen content of

  16. 2D zirconium fluorides: Synthesis, structure and NMR spectroscopy

    NASA Astrophysics Data System (ADS)

    Ben Ali, A.; Body, M.; Leblanc, M.; Maisonneuve, V.

    2011-02-01

    Two new zirconium (IV) fluorides, [H 2dap]·(Zr 2F 10)·H 2O ( I) and [H meam] 2·(Zr 2F 10)·H 2O ( II), are synthesized and characterized by X-ray diffraction, thermal techniques and NMR spectroscopy. I is triclinic ( P1¯) with a = 6.805 (1) Å, b = 8.361(1) Å, and c = 11.853 (2) Å, ? = 94.54(1)°, ? = 105.44(1)°, ? = 108.75(1)°. II is monoclinic ( C2 /m) with a = 10.340(6) Å, b = 6.624(4) Å, c = 8.758(6) Å and ? = 110.57(3)°. The structure determinations, performed from single crystal X-ray diffraction data, lead to the R/R w reliability factors 0.041/0.113 for I and 0.057/0.177 for II. The structures are built up from ZrF 7 and ZrF 8 units in I and only ZrF 8 units in II. The polyhedra share common edges in order to form two different ZrF 5 layers that are also found in [H 2C2H10N2]·(Zr 2F 10)·H 2O and (H 3O) 2·(Zr 2F 10)·H 2O. On heating at 145 °C, [H 2dap]·(Zr 2F 10)·H 2O decomposes to give the anhydrous form [H 2dap]·(Zr 2F 10) that undergoes two successive phase transformations at 220 °C and 290 °C. 19F NMR spectroscopy confirms the structural features of [H 2dap]·(Zr 2F 10)·H 2O ( I): two sets of three lines with a relative intensity 1:2:2 are attributed to five bridging fluorine atoms and to five nonbridging fluorine atoms. This spectroscopy demonstrates that a noticeable substitution of F - anions by hydroxyl OH - groups is excluded, together with the eventual substitution of H 2O by HF molecules.

  17. Trivalent metallocene chemistry of some uranium, titanium, and zirconium complexes

    SciTech Connect

    Lukens, W.W. Jr.

    1995-05-01

    Dicyclopentadienyluranium halide dimers have been prepared and their solution behavior examined. These molecules exist as dimers in solution, and the halide ligands undergo rapid site exchange on the NMR timescale above 50 C. Analogous dicyclopentadienyluranium hydroxide dimers have also been prepared; they oxidatively eliminate hydrogen to give the corresponding oxide dimers. Mechanism of this reaction is consistent with {alpha}migration of one of the hydroxide hydrogen atoms to a uranium center followed by elimination of hydrogen. Ground state of [(Me{sub 3}Si){sub 2}C{sub 5}H{sub 3}]{sub 3}M M = Nd, U and their base adducts has been examined by variable temperature magnetic susceptibility and EPR spectroscopy. The ground state is found to be {sup 4}I{sub 9/2} with a crystal field state consisting largely of J{sub z} = 1/2 lowest, in agreement with previous studies on tris-cyclopentadienylneodymium complexes. The zirconium metallocene Cp{sub 3}Zr has been prepared, characterized crystallographically, and its reactivity studied. Its chemical behavior is controlled by presence of an electron in the non-bonding, d{sub z}2 orbital which prevents formation of base adducts Of Cp{sub 3}Zr, but allows Cp{sub 3}Zr to abstract atoms from other molecules. Electonic and EPR spectra of Cp*{sub 2}TiX complexes, where Cp* is Me{sub 5}C{sub 5} and X is a monodentate, anionic ligand such as halide, have been studied. A {pi}-bonding spectrochemical series is developed, and trends in {pi}-bonding ability are found similar to those in other inorganic complexes. The {beta}-agostic interactions in Cp*{sub 2}TiN(Me)Ph have been examined using variable temperature EPR spectroscopy, and the enthalpy/entropy of the interaction determined. In Cp*{sub 2}TiEt, enthalpy of the {beta}-agostic interaction is {minus}1.9 kcal/mol. The titanocene anion, Cp*{sub 2}TiLi(TMEDA) (TMEDA is N,N,N`,N`-tetramethylethylenediamine), has been prepared and its structure determined.

  18. Composition and microstructure of zirconium and hafnium germanates obtained by different chemical routes

    SciTech Connect

    Utkin, A.V., E-mail: utkinalex@hotmail.com; Prokip, V.E.; Baklanova, N.I.

    2014-01-15

    The phase composition and morphology of zirconium and hafnium germanates synthesized by ceramic and co-precipitation routes were studied. The products were characterized using high-temperature X-ray diffraction analysis (XRD), Raman spectroscopy, scanning electron microscopy (SEM) and thermal (TG/DTA) analysis. To investigate the phase composition and stoichiometry of compounds the unit cell parameters were refined by full-profile Rietveld XRD analysis. The morphology of products and its evolution during high-temperature treatment was examined by SEM analysis. It was stated that there is the strong dependence of the phase composition and morphology of products on the preparation route. The ceramic route requires a multi-stage high-temperature treatment to obtain zirconium and hafnium germanates of 95% purity or more. Also, there are strong diffusion limitations to obtain hafnium germanate Hf{sub 3}GeO{sub 8} by ceramic route. On the contrary, the co-precipitation route leads to the formation of nanocrystalline single phase germanates of stoichiometric composition at a relatively low temperatures (less than 1000 °C). The results of quantitative XRD analysis showed the hafnium germanates are stoichiometric compounds in contrast to zirconium germanates that form a set of solid solutions. This distinction may be related to the difference in the ion radii of Zr and Hf. - Graphical abstract: The phase composition and morphology of zirconium and hafnium germanates synthesized by ceramic and co-precipitation routes were studied. It was stated that there is the strong dependence of the phase composition and morphology of products on the preparation route. Display Omitted - Highlights: • Zr and Hf germanates were synthesized by ceramic and co-precipitation routes. • The morphology of products depends on the synthesis parameters. • Zirconium germanates forms a set of solid solutions. • Hafnium germanates are stoichiometric compounds.

  19. Removal of uranium(VI) from aqueous solutions and nuclear industry effluents using humic acid-immobilized zirconium-pillared clay.

    PubMed

    Anirudhan, T S; Bringle, C D; Rijith, S

    2010-03-01

    Removal of uranium [U(VI)] from aqueous solutions with humic acid-immobilized zirconium-pillared clay (HA-Zr-PILC) was investigated using a batch adsorption technique. The adsorbent was characterized using XRD, FTIR, SEM, TG/DTG, surface area analyzer and potentiometric titration. The effects of pH, contact time, initial concentration, adsorbent dose, and adsorption isotherm on the removal process were evaluated. A maximum removal of 97.6+/-2.1 and 94.7+/-3.3% was observed for an initial concentration of 50 and 100 mg L(-1), respectively at pH 6.0 and an adsorbent dose of 2.0 g L(-1). Equilibrium was achieved in approximately 180 min. The mechanism for the removal of U(VI) ions by HA-Zr-PILC was based on an ion exchange reaction. The experimental kinetic and isotherm data were analyzed using a second-order kinetic equation and Langmuir isotherm model, respectively. The monolayer adsorption capacity for U(VI) removal was found to be 132.68+/-5.04 mg g(-1). An increase of temperature of the medium caused an increase in metal adsorption. Complete removal (approximately = 100%) of U(VI) from 1.0 L of a simulated nuclear industry effluent sample containing 10.0 mg U(VI) ions was possible with 1.5 g of HA-Zr-PILC. The adsorbent was suitable for repeated use (over 4 cycles) without any noticeable loss of capacity. PMID:20045229

  20. Zirconium phosphatidylcholine-based nanocapsules as an in vivo degradable drug delivery system of MAP30, a momordica anti-HIV protein.

    PubMed

    Caizhen, Guo; Yan, Gao; Ronron, Chang; Lirong, Yang; Panpan, Chu; Xuemei, Hu; Yuanbiao, Qiao; Qingshan, Li

    2015-04-10

    An essential in vivo drug delivery system of a momordica anti-HIV protein, MAP30, was developed through encapsulating in chemically synthesized matrices of zirconium egg- and soy-phosphatidylcholines, abbreviated to Zr/EPC and Zr/SPC, respectively. Matrices were characterized by transmission electron microscopy and powder X-ray diffractometry studies. Zr/EPC granule at an approximate diameter of 69.43±7.78nm was a less efficient encapsulator than the granule of Zr/SPC. Interlayer spacing of the matrices encapsulating MAP30 increased from 8.8 and 9.7Å to 7.4 and 7.9nm, respectively. In vivo kinetics on degradation and protein release was performed by analyzing the serum sampling of intravenously injected SPF chickens. The first order and biphasic variations were obtained for in vivo kinetics using equilibrium dialysis. Antimicrobial and anti-HIV assays yielded greatly decreased MIC50 and EC50 values of nanoformulated MAP30. An acute toxicity of MAP30 encapsulated in Zr/EPC occurred at a single intravenous dose above 14.24mg/kg bw in NIH/KM/ICR mice. The folding of MAP30 from Zr/EPC sustained in vivo chickens for more than 8 days in high performance liquid chromatography assays. These matrices could protect MAP30 efficiently with strong structure retention, lowered toxicity and prolonged in vivo life. PMID:25681721

  1. Development and evaluation of the TD97 measles virus vaccine

    SciTech Connect

    Suzuki, K.; Morita, M.; Katoh, M.; Kidokoro, M.; Saika, S.; Yoshizawa, S.; Hashizume, S.; Horiuchi, K.; Okabe, N.; Shinozaki, T. (Chiba Serum Institute (Japan))

    1990-11-01

    The TD97 strain vaccine virus was prepared from the Tanabe strain measles virus by low-temperature passages in primary cell cultures and ultraviolet (UV) mutagenesis. The TD97 strain exhibited the following characteristics: highly temperature sensitive, neither multiplying nor forming any plaques at 40 degrees C in Vero cells; genetically stable, maintaining high temperature sensitivity after ten successive passages in CE cells at 30 degrees C or 35 degrees C; and M proteins of this virus about 1 KD slower in mobility in SDS-PAGE than that of the Tanabe strain. The TD97 strain was further confirmed to be attenuated by an inoculation test into primate brain. In field trials, 752 healthy children were inoculated with a live virus vaccine prepared with this strain, and the following results were obtained: the seroconversion rate was 97% (517/533), and the average HI antibody titer was 2(5.2). An antibody-increasing effect was also observed in children who were initially seropositive. In children who seroconverted, the rates of fever were 15.7% (55/351) for 37.5 degrees C or higher and 4.0% (14/351) for 39 degrees C or higher. The rash rate was 7.7% (27/351), and the incidence of local reaction was 5.4% (19/351). The TD97 strain is thus considered to be suitable in use for an attenuated measles vaccine.

  2. The effect of sulfur and zirconium co-doping on the oxidation of NiCrAl

    NASA Technical Reports Server (NTRS)

    Smialek, James L.

    1988-01-01

    The adhesion behavior of Al2O3 scales formed on NiCrAl+Zr alloys was examined as a function of both sulfur and zirconium doping levels. In general, very high levels of zirconium were required to counteract the detrimental effects of sulfur. A sulfur-zirconium adherence map was constructed, as determined from the oxidation and spalling behavior in 1100 C cyclic tests. For low sulfur alloys (less than 500 ppma), the amount of zirconium required for adherence at any given sulfur level can be described by Zr greater than 600 S(0.2) (in ppma). These results underscore the importance of sulfur to adhesion mechanisms and suggest that sulfur gettering is a first order effect of reactive element additions to MCrAl alloys.

  3. In Situ Enrichment of Phosphopeptides on MALDI Plates Functionalized by Reactive Landing of Zirconium(IV)–n-Propoxide Ions

    PubMed Central

    Blacken, Grady R.; Volný, Michael; Vaisar, Tomáš; Sadílek, Martin; Ture?ek, František

    2008-01-01

    We report substantial in situ enrichment of phosphopeptides in peptide mixtures using zirconium oxide coated plates for detection by MALDI-TOF mass spectrometry. The novel feature of this approach rests on the specific preparation of zirconium oxide coatings using reactive landing on stainless steel support of gas-phase positive ions produced by electrospray of zirconium(IV)–n-propoxide solutions in 1-propanol. Reactive landing was found to produce durable functionalized surfaces for selective phosphopeptide capture and desorption–ionization by MALDI. Enrichment factors on the order of 20–90 were achieved for several monophosphorylated peptides relative to abundant nonphosphorylated peptides in tryptic digests. We demonstrate the ability of the zirconium oxide functionalized MALDI surfaces to facilitate detection of enriched phosphopeptides in mid-femtomole amounts of ?-casein digests per MALDI spot. PMID:17569507

  4. Characterization of Alpha-Phase Sintering of Uranium and Uranium-Zirconium Alloys for Advanced Nuclear Fuel Applications

    E-print Network

    Helmreich, Grant

    2012-02-14

    The sintering behavior of uranium and uranium-zirconium alloys in the alpha phase were characterized in this research. Metal uranium powder was produced from pieces of depleted uranium metal acquired from the Y-12 plant via hydriding...

  5. Thermal analysis of uranium zirconium hydride fuel using a lead-bismuth gap at LWR operating temperatures

    E-print Network

    Ensor, Brendan M. (Brendan Melvin)

    2012-01-01

    Next generation nuclear technology calls for more advanced fuels to maximize the effectiveness of new designs. A fuel currently being studied for use in advanced light water reactors (LWRs) is uranium zirconium hydride ...

  6. Effect of the flame temperature on the characteristics of zirconium oxide fine particle synthesized by flame assisted spray pyrolysis

    NASA Astrophysics Data System (ADS)

    Widiyastuti, W.; Machmudah, Siti; Nurtono, Tantular; Winardi, Sugeng

    2013-09-01

    Zirconium oxide fine particles were synthesized by flame assisted spray pyrolysis using zirconium chloride solution as precursor. Propane gas and air were used as a fuel and an oxidizer, respectively. The ratio of flow rate of oxidizer and fuel was maintained constant at 10:1 to ensure a complete combustion. Increasing fuel flow rate led to the increase of temperature distribution in the flame reactor. The intensity of XRD patterns increased with temperature and precursor concentration. Phase composition of zirconium oxide produced by this process consisted of monoclinic and tetragonal phases. The volume fraction of monoclinic phase of zirconium oxide increased with temperature and precursor concentration. The morphology particles observed by SEM resulted in spherical particles with size in the submicron range depending on the precursor concentration.

  7. Synthesis and structural characterisation using Rietveld and pair distribution function analysis of layered mixed titanium-zirconium phosphates

    NASA Astrophysics Data System (ADS)

    Burnell, Victoria A.; Readman, Jennifer E.; Tang, Chiu C.; Parker, Julia E.; Thompson, Stephen P.; Hriljac, Joseph A.

    2010-09-01

    Crystalline metal (IV) phosphates with variable zirconium-to-titanium molar ratios of general formula (Ti 1- xZr x)(HPO 4) 2·H 2O have been prepared by precipitation of soluble salts of the metals with phosphoric acid and heating the amorphous solids in 12 M H 3PO 4 in an autoclave. The new materials are structurally characterised by Rietveld analysis of synchrotron X-ray powder diffraction data and pair distribution function (PDF) analysis of high energy synchrotron X-ray total scattering data. A broad range of zirconium-titanium phosphate solid solutions were formed showing isomorphous substitution of titanium by zirconium in the ?-titanium phosphate lattice and vice versa for titanium substitution into the ?-zirconium phosphate lattice. In both cases the solubility is partial with the coexistence of two substituted phases observed in samples with nominal compositions between the solubility limits.

  8. Human biokinetic data and a new compartmental model of zirconium--a tracer study with enriched stable isotopes.

    PubMed

    Greiter, Matthias B; Giussani, Augusto; Höllriegl, Vera; Li, Wei Bo; Oeh, Uwe

    2011-09-01

    Biokinetic models describing the uptake, distribution and excretion of trace elements are an essential tool in nutrition, toxicology, or internal dosimetry of radionuclides. Zirconium, especially its radioisotope (95)Zr, is relevant to radiation protection due to its production in uranium fission and neutron activation of nuclear fuel cladding material. We present a comprehensive set of human data from a tracer study with stable isotopes of zirconium. The data are used to refine a biokinetic model of zirconium. Six female and seven male healthy adult volunteers participated in the study. It includes 16 complete double tracer investigations with oral ingestion and intravenous injection, and seven supplemental investigations. Tracer concentrations were measured in blood plasma and urine collected up to 100 d after tracer administration. The four data sets (two chemical tracer forms in plasma and urine) each encompass 105-240 measured concentration values above detection limits. Total fractional absorption of ingested zirconium was found to be 0.001 for zirconium in citrate-buffered drinking solution and 0.007 for zirconium oxalate solution. Biokinetic models were developed based on the linear first-order kinetic compartmental model approach used by the International Commission on Radiological Protection (ICRP). The main differences of the optimized systemic model of zirconium to the current ICRP model are (1) recycling into the transfer compartment made necessary by the observed tracer clearance from plasma, (2) different parameters related to fractional absorption for each form of the ingested tracer, and (3) a physiologically based excretion pathway to urine. The study considerably expands the knowledge on the biokinetics of zirconium, which was until now dominated by data from animal studies. The proposed systemic model improves the existing ICRP model, yet is based on the same principles and fits well into the ICRP radiation protection approach. PMID:21724239

  9. Optical, structural, and electrical characteristics of high dielectric constant zirconium oxide thin films deposited by spray pyrolysis

    Microsoft Academic Search

    M. Aguilar-Frutis; G. Reyna-Garcia; M. Garcia-Hipolito; J. Guzman-Mendoza; C. Falcony

    2004-01-01

    The spray pyrolysis technique was used to obtain high dielectric constant zirconium oxide films. These films were deposited on silicon substrates, and quartz slides from two different solution concentrations (0.033 and 0.066 M) of zirconium acetylacetonate dissolved in N,N-dimethylformamide at substrate temperatures in the range of 400-600 °C. The films are transparent with a surface roughness lower than 40 Å

  10. HDAC6-p97/VCP controlled polyubiquitin chain turnover.

    PubMed

    Boyault, Cyril; Gilquin, Benoit; Zhang, Yu; Rybin, Vladimir; Garman, Elspeth; Meyer-Klaucke, Wolfram; Matthias, Patrick; Müller, Christoph W; Khochbin, Saadi

    2006-07-26

    HDAC6 is a unique cytoplasmic deacetylase capable of interacting with ubiquitin. Using a combination of biophysical, biochemical and biological approaches, we have characterized the ubiquitin-binding domain of HDAC6, named ZnF-UBP, and investigated its biological functions. These studies show that the three Zn ion-containing HDAC6 ZnF-UBP domain presents the highest known affinity for ubiquitin monomers and mediates the ability of HDAC6 to negatively control the cellular polyubiquitin chain turnover. We further show that HDAC6-interacting chaperone, p97/VCP, dissociates the HDAC6-ubiquitin complexes and counteracts the ability of HDAC6 to promote the accumulation of polyubiquitinated proteins. We propose that a finely tuned balance of HDAC6 and p97/VCP concentrations determines the fate of ubiquitinated misfolded proteins: p97/VCP would promote protein degradation and ubiquitin turnover, whereas HDAC6 would favour the accumulation of ubiquitinated protein aggregates and inclusion body formation. PMID:16810319

  11. Protection of zirconium by alumina- and chromia-forming iron alloys under high-temperature steam exposure

    NASA Astrophysics Data System (ADS)

    Terrani, Kurt A.; Parish, Chad M.; Shin, Dongwon; Pint, Bruce A.

    2013-07-01

    The viability of advanced oxidation-resistant Fe-base alloys to protect zirconium from rapid oxidation in high-temperature steam environments has been examined. Specimens were produced such that outer layers of FeCrAl ferritic alloy and Type 310 austenitic stainless steel were incorporated on the surface of zirconium metal slugs. The specimens were exposed to high-temperature 0.34 MPa steam at 1200 and 1300 °C. The primary degradation mechanism for the protective layer was interdiffusion with the zirconium, as opposed to high-temperature oxidation in steam. The FeCrAl layer experienced less degradation and protected the zirconium at 1300 °C for 8 h. Constituents of the Fe-base alloys rapidly diffused into the zirconium and resulted in the formation of various intermetallic layers at the interface and precipitates inside the bulk zirconium. The nature of this interaction for FeCrAl and 310SS has been characterized by use of microscopic techniques as well as computational thermodynamics. Finally, a reactor physics discussion on the applicability of these protective layers in light-water-reactor nuclear fuel structures is offered.

  12. Tribological evaluation of oxidized zirconium using an articular cartilage counterface: a novel material for potential use in hemiarthroplasty.

    PubMed

    Patel, A M; Spector, M

    1997-03-01

    Problems with total joint replacement that have surfaced in recent years have made reconsideration of more conservative hip reconstructive procedures compelling. Moreover, procedures such as hemiarthroplasty might benefit from newly developed materials that could provide more favourable tribological performance when employed as a counterface for articulation with articular cartilage. The objective of this study was to evaluate the tribology of a new biomaterial, oxidized zirconium, with articular cartilage in a laboratory test apparatus. Oxidized zirconium components are produced by oxidizing the zirconium alloy to form a relatively thick (7 microns), adherent, abrasion-resistant ceramic surface. We found that the coefficient of friction of bovine articular cartilage rubbed against oxidized zirconium was lower than with cobalt-chromium alloy control surfaces, and that there was a trend toward less wear with oxidized zirconium. A defined layer of degraded tissue was found on the surface of the articular cartilage specimens, providing some indication of the mechanism of wear. Results of this study warrant further investigation of oxidized zirconium as the bearing surface for hemiarthroplasty. PMID:9061186

  13. Influence of zirconium doping on the activities of zirconium and iodine co-doped titanium dioxide in the decolorization of methyl orange under visible light irradiation

    NASA Astrophysics Data System (ADS)

    Song, Shuang; Hong, Fangyue; He, Zhiqiao; Wang, Hongyu; Xu, Xianghong; Chen, Jianmeng

    2011-09-01

    Zirconium and iodine co-doped titanium dioxide (Zr-I-TiO2) was prepared by the hydrolysis of tetrabutyl titanate, premixed with zirconium nitrate in an iodic acid aqueous solution, followed by calcination in air. The structure and properties of the resultant catalyst powders were characterized by X-ray diffraction, the Brunauer-Emmett-Teller method, X-ray photoelectron spectroscopy, transmission electron microscopy, and UV-vis absorption spectroscopy. The catalytic activity of the catalyst was evaluated by monitoring the photocatalytic decolorization of methyl orange under visible light irradiation. The results showed that the activities of Zr-I-TiO2 catalysts were higher than that of TiO2 doped with iodine alone (I-TiO2), and the optimal doping concentration in the Zr-I-TiO2 calcined at 400 °C was determined to be about 0.05 (molar ratio of Zr:Ti). In addition, the photocatalytic activity of Zr-I-TiO2 calcined at 400 °C was found to be significantly higher than that calcined at 500 or 600 °C. Based on the physico-chemical characterization, we concluded that the role of zirconium on the I-TiO2 surface is to increase the number of reactive sites by generating a small crystal size and large surface area. The inhibition of electron-hole pair recombination, by trapping photo-generated electrons with Zr4+, did not contribute markedly to the improved photocatalytic activity of Zr-I-TiO2.

  14. Determination of nanogram levels of zirconium by chelating ion exchange and on-line preconcentration in flow injection UV-visible spectrophotometry.

    PubMed

    Purohit, R; Devi, S

    1997-03-01

    Trace quantities of zirconium were preconcentrated on a series of chelating resins. The experimental conditions for preconcentration such as pH, time and metal ion concentration were optimized for the batch processes. Continuous flow manifolds were developed for the on-line preconcentration of zirconium using microcolumns containing chelating resins. Calibration plots were obtained with correlation coefficients of 0.9990 +/- 0.0008. The determination of zirconium was performed using Xylenol Orange at 535 nm. Binary and ternary mixtures of zirconium, thorium and titanium did not show any cross-contamination during column chromatographic separation. PMID:18966749

  15. Synthesis of amorphous supermicroporous zirconium phosphate materials by nonionic surfactant templating

    SciTech Connect

    Zhao, G.L. [College of Chemistry and Life Science, Zhejiang Normal University, Jinhua 321004, Zhejiang Province (China); Yuan, Z.Y. [College of Chemistry, Nankai University, Tianjin 300071 (China)]. E-mail: zyyuan@mail.nankai.edu.cn; Chen, T.H. [College of Chemistry, Nankai University, Tianjin 300071 (China)

    2005-11-03

    Supermicroporous zirconium phosphate materials possessing wormhole-like pores in the size range 1.3-1.8 nm were synthesized by using nonionic poly(ethylene oxide) surfactant (e.g., C{sub 16}H{sub 33}(EO){sub 10}, C{sub 18}H{sub 35}(EO){sub 10}) as a structure directing agent. The textural and structural properties were characterized by powder X-ray diffraction, N{sub 2} adsorption analysis, differential thermal analysis, scanning and transmission electron microscopy, {sup 31}P MAS NMR and infrared spectroscopy. The synthesized materials are amorphous, exhibiting high surface areas, narrow pore size distributions, excellent thermal stabilities (over 800 deg. C) and acidic properties. The supermicropore size of the synthesized zirconium phosphate may be tunable by the variation of alkyl chain length of the surfactant.

  16. Methods of mathematical statistics for verification of hydrogen content in zirconium hydride moderator

    SciTech Connect

    Ponomarev-Stepnoi, N.N.; Bubelev, V.G.; Glushkov, Ye.S.; Kompaniets, G.V.; Nosov, V.I. (Kurchatov Inst. Russian Research Centre, Moscow (Russian Federation))

    1995-02-01

    The hydrogen content of zirconium hydride blocks used as the moderator in Topaz-2-type space reactors is estimated according to correlation-regression analysis procedures of mathematical statistics and is based on the results of the definition of the reactivity of the blocks in a research critical assembly. A linear mathematical model for a variable response is formulated within the framework of the first-order perturbation theory applied to the estimation of reactivity effects in reactors. A PASPORT computer code is written based on the developed algorithm. The statistical analysis of the available data performed by using PASPORT shows that the developed approach allows determination of the insignificance of the contribution of the impurities to the reactivity of the blocks, verification of the manufacturer's data on the hydrogen content in zirconium hydride blocks, and estimation of the reactivity shift in a standard block.

  17. Effects of crystallographic orientation on plastic deformation and SCC initiation of zirconium alloys

    NASA Astrophysics Data System (ADS)

    Kubo, T.; Wakashima, Y.; Amano, K.; Nagai, M.

    1985-05-01

    In order to investigate the effects of crystallographic orientation on deformation and crack initiation in iodine-induced SCC of zirconium alloys, uniaxial tensile tests of zirconium and Zircaloy-2 plates were conducted in an iodine atmosphere. The crystallographic orientation of individual grains was determined by an etch-pit technique prior to testing. After testing, the etch-pit technique showed that prismatic slip was predominant in the plastic deformation and that cleavage cracks extended along basal planes. The plastic deformation of individual grains was significantly influenced by their crystallographic orientations, which varied from one grain to another. Accordingly, inhomogeneous plastic deformation occurred between grains. The crack initiation took place preferentially at grain boundaries where differences of crystallographic orientations were large between adjacent grains. This indicated that crack initiations was caused by stress concentration due to strain incompatibility at those grain boundaries.

  18. Electrotransport and diffusivity of molybdenum, rhenium, tungsten, and zirconium in beta-thorium

    NASA Technical Reports Server (NTRS)

    Schmidt, F. A.; Beck, M. S.; Rehbein, D. K.; Conzemius, R. J.; Carlson, O. N.

    1984-01-01

    The electric mobilities, diffusivities, and effective valences were determined for molybdenum, rhenium, tungsten, and zirconium in beta-thorium. All four solutes migrated in the same direction as the electron flow. Rhenium and molybdenum were found to be very mobile, with tungsten somewhat slower. Zirconium was found to move at a rate near that of the self-diffusion of beta-thorium, viz., about 10 to the -11th sq m/s at 1500 C. The electromigration velocities showed a similar trend. A comparison was made between experimental data obtained by scanning laser mass spectrometry and theoretical transport equations for two purification experiments. Good agreement was obtained with both the concentration profile predicted by DeGroot and the purification ratio predicted by Verhoeven.

  19. Effect of competitive ions on the arsenic removal by mesoporous hydrous zirconium oxide from drinking water

    SciTech Connect

    Bortun, Anatoly; Bortun, Mila; Pardini, James [MEL Chemicals Inc., 500 Barbertown Point Breeze Road, Flemington, NJ 08822 (United States)] [MEL Chemicals Inc., 500 Barbertown Point Breeze Road, Flemington, NJ 08822 (United States); Khainakov, Sergei A. [Departamento de Quimica Organica e Inorganica, Universidad de Oviedo, C/ Julian Claveria, 8, 33006 Oviedo (Spain)] [Departamento de Quimica Organica e Inorganica, Universidad de Oviedo, C/ Julian Claveria, 8, 33006 Oviedo (Spain); Garcia, Jose R., E-mail: jrgm@uniovi.es [Departamento de Quimica Organica e Inorganica, Universidad de Oviedo, C/ Julian Claveria, 8, 33006 Oviedo (Spain)

    2010-11-15

    Adsorption properties of 302-type commercially available hydrous zirconium oxide (302-HZO) towards arsenic and some competitive anions and cations have been studied under batch and column conditions. Due to amphoteric properties, anion exchange performance of hydrous zirconium oxide is pH dependent. Media exhibits high affinity towards arsenic in a broad pH range, with high adsorption capacity at pH < 8. It was shown that silicate and phosphate ions are arsenic's main competitors affecting media adsorption capacity. Presence of transition metal cations in <1 ppm does not affect 302-HZO capacity on arsenic, whereas alkaline-earth cations improve arsenic removal. The possibility for significant increase of 302-HZO adsorption capacity on arsenic at pH > 8 by using 'solid acidifier' technique is discussed. Results of 302-HZO field trials are presented.

  20. Recent irradiation tests of uranium-plutonium-zirconium metal fuel elements

    SciTech Connect

    Pahl, R.G.; Lahm, C.E.; Villarreal, R.; Hofman, G.L.; Beck, W.N.

    1986-09-01

    Uranium-Plutonium-Zirconium metal fuel irradiation tests to support the ANL Integral Fast Reactor concept are discussed. Satisfactory performance has been demonstrated to 2.9 at.% peak burnup in three alloys having 0, 8, and 19 wt % plutonium. Fuel swelling measurements at low burnup in alloys to 26 wt % plutonium show that fuel deformation is primarily radial in direction. Increasing the plutonium content in the fuel diminishes the rate of fuel-cladding gap closure and axial fuel column growth. Chemical redistribution occurs by 2.1 at.% peak burnup and generally involves the inward migration of zirconium and outward migration of uranium. Fission gas release to the plenum ranges from 46% to 56% in the alloys irradiated to 2.9 at.% peak burnup. No evidence of deleterious fuel-cladding chemical or mechanical interaction was observed.