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Sample records for hafnium 154

  1. Commercial production of metal hafnium and hafnium-based products

    International Nuclear Information System (INIS)

    Negodin, D.A.; Shtutsa, M.G.; Akhtonov, S.G.; Il'enko, E.V.; Kobyzev, A.M.

    2012-01-01

    Hafnium possesses a unique complex of physical and chemical properties which allow the application of products on its basis in various industries. Joint Stock Company 'Chepetsky Mechanical Plant' is the single enterprise which produces hafnium on the territory of Russia. The manufacture of metal hafnium with the total content of zirconium and hafnium, at least, 99,8 % of weights is developed at the present time at Joint Stock Company CHMZ. The weight of melted hafnium ingots is up to 1 ton. Manufacture of wide range of products from hafnium is implemented. The plates from a hafnium with thickness of 0.60 mm which are used for emergency control cartridges of VVER-440 reactors are the most critical product. It is shown that ingots and products obtained from metal hafnium correspond to the Russian and international standards for reactor materials in chemical composition, mechanical and corrosion properties.

  2. Metallurgy of zirconium and hafnium

    International Nuclear Information System (INIS)

    Baryshnikov, N.V.; Geger, V.Eh.; Denisova, N.D.; Kazajn, A.A.; Kozhemyakin, V.A.; Nekhamkin, L.G.; Rodyakin, V.V.; Tsylov, Yu.A.

    1979-01-01

    Considered are those properties of zirconium and of hafnium, which are of practical interest for the manufacture of these elements. Systematized are the theoretical and the practical data on the procedures for thermal decomposition of zirconia and for obtaining zirconium dioxide and hafnium dioxide by a thermal decomposition of compounds and on the hydrometallurgical methods for extracting zirconium and hafnium. Zirconium and hafnium fluorides and chlorides production procedures are described. Considered are the iodide and the electrolytic methods of refining zirconium and hafnium

  3. Gravimetric determination of hafnium through its arsenate in carbide and boride of hafnium

    International Nuclear Information System (INIS)

    Rasulbekova, R.A.; Mamedov, I.A.

    1976-01-01

    A gravimetric method of determining hafnium through hydroarsenate has been recommended. The method differs from the known ones by its simplicity and by the recalculation coefficient which is more than by 50% smaller than that used in preparing a weight form of HfO 2 . Upon development of gravimetric determination of hafnium through hydro-and pyroarsenate, an investigation has been conducted with the aim to find some physico-chemical constants of hafnium hydroarsenate. The weighed amount of hafnium hydroarsenate is dissolved in sulphuric acid (2:5). The precipitate of hafnium hydroarsenate has been studied for recording infrared absorption spectra. Thermographic analysis of the precipitate has been performed. Thermogram reveals endothermal effect at 105 deg C and exothermal at 840 deg C. Water solubility of hafnium has been determined equal to 1.75x10 6 g mol/l. The corresponding solubility product of the precipitate has been calculated which is 2.1x10 -17 . It is shown that the method possesses certain selectivity, sufficient accuracy, and is rather fast. It has been established that determination can be performed in the presence of excess amounts of ions

  4. Hafnium isotope stratigraphy of ferromanganese crusts

    Science.gov (United States)

    Lee; Halliday; Hein; Burton; Christensen; Gunther

    1999-08-13

    A Cenozoic record of hafnium isotopic compositions of central Pacific deep water has been obtained from two ferromanganese crusts. The crusts are separated by more than 3000 kilometers but display similar secular variations. Significant fluctuations in hafnium isotopic composition occurred in the Eocene and Oligocene, possibly related to direct advection from the Indian and Atlantic oceans. Hafnium isotopic compositions have remained approximately uniform for the past 20 million years, probably reflecting increased isolation of the central Pacific. The mechanisms responsible for the increase in (87)Sr/(86)Sr in seawater through the Cenozoic apparently had no effect on central Pacific deep-water hafnium.

  5. SEPARATION OF HAFNIUM FROM ZIRCONIUM

    Science.gov (United States)

    Overholser, L.B.; Barton, C.J. Sr.; Ramsey, J.W.

    1960-05-31

    The separation of hafnium impurities from zirconium can be accomplished by means of organic solvent extraction. The hafnium-containing zirconium feed material is dissolved in an aqueous chloride solution and the resulting solution is contacted with an organic hexone phase, with at least one of the phases containing thiocyanate. The hafnium is extracted into the organic phase while zirconium remains in the aqueous phase. Further recovery of zirconium is effected by stripping the onganic phase with a hydrochloric acid solution and commingling the resulting strip solution with the aqueous feed solution. Hexone is recovered and recycled by means of scrubbing the onganic phase with a sulfuric acid solution to remove the hafnium, and thiocyanate is recovered and recycled by means of neutralizing the effluent streams to obtain ammonium thiocyanate.

  6. Zirconium and hafnium

    Science.gov (United States)

    Jones, James V.; Piatak, Nadine M.; Bedinger, George M.; Schulz, Klaus J.; DeYoung,, John H.; Seal, Robert R.; Bradley, Dwight C.

    2017-12-19

    Zirconium and hafnium are corrosion-resistant metals that are widely used in the chemical and nuclear industries. Most zirconium is consumed in the form of the main ore mineral zircon (ZrSiO4, or as zirconium oxide or other zirconium chemicals. Zirconium and hafnium are both refractory lithophile elements that have nearly identical charge, ionic radii, and ionic potentials. As a result, their geochemical behavior is generally similar. Both elements are classified as incompatible because they have physical and crystallochemical properties that exclude them from the crystal lattices of most rock-forming minerals. Zircon and another, less common, ore mineral, baddeleyite (ZrO2), form primarily as accessory minerals in igneous rocks. The presence and abundance of these ore minerals in igneous rocks are largely controlled by the element concentrations in the magma source and by the processes of melt generation and evolution. The world’s largest primary deposits of zirconium and hafnium are associated with alkaline igneous rocks, and, in one locality on the Kola Peninsula of Murmanskaya Oblast, Russia, baddeleyite is recovered as a byproduct of apatite and magnetite mining. Otherwise, there are few primary igneous deposits of zirconium- and hafnium-bearing minerals with economic value at present. The main ore deposits worldwide are heavy-mineral sands produced by the weathering and erosion of preexisting rocks and the concentration of zircon and other economically important heavy minerals, such as ilmenite and rutile (for titanium), chromite (for chromium), and monazite (for rare-earth elements) in sedimentary systems, particularly in coastal environments. In coastal deposits, heavy-mineral enrichment occurs where sediment is repeatedly reworked by wind, waves, currents, and tidal processes. The resulting heavy-mineral-sand deposits, called placers or paleoplacers, preferentially form at relatively low latitudes on passive continental margins and supply 100 percent of

  7. Molten salt scrubbing of zirconium or hafnium tetrachloride

    International Nuclear Information System (INIS)

    Lee, E.D.; McLaughlin, D.F.

    1990-01-01

    This patent describes a continuous process for removing impurities of iron or aluminum chloride or both from vaporous zirconium or hafnium chloride or both. It comprises: introducing impure zirconium or hafnium chloride vapor or both into a middle portion of an absorbing column containing a molten salt phase, the molten salt phase absorbing the impurities of iron or aluminum chloride or both to produce chloride vapor stripped of zirconium or hafnium chloride; introducing sodium or potassium chloride or both into a top portion of the column; controlling the top portion of the column to between 300--375 degrees C.; heating a bottom portion of the column to 450--550 degrees C. To vaporize zirconium chloride or hafnium chloride or hafnium and zirconium chloride from the molten salt; withdrawing molten salt substantially free of zirconium and hafnium chloride from the bottom portion of the column; and withdrawing zirconium chloride or hafnium chloride or hafnium and zirconium chloride vapor substantially free of impurities of iron and aluminum chloride from the top of the column

  8. Recovery of hafnium values from loaded extraction solvent

    International Nuclear Information System (INIS)

    Abodishish, H.A.

    1989-01-01

    This patent describes an improvement in a process for recovering high purity hafnium hydroxide from a methyl isobutyl ketone organic solvent that is substantially free of sulfate ions and contains hafnium thiocyanate and thiocyanic acid. The improvement comprising reacting the organic solvent with ammonia to produce a reaction product in the form of a methyl isobutyl ketone organic solvent that is substantially free of sulfate ions and contains ammonium thiocyanite solution and hafnium hydroxide; separating the constituents of the reaction product in accordance with their respective specific gravities to produce a hafnium hydroxide sludge as one of the separation products; and removing the liquid component of the sludge to yield a high purity hafnium hydroxide ready for calcination to hafnium oxide

  9. Hafnium carbide formation in oxygen deficient hafnium oxide thin films

    Energy Technology Data Exchange (ETDEWEB)

    Rodenbücher, C. [Forschungszentrum Jülich GmbH, Peter Grünberg Institute (PGI-7), JARA-FIT, 52425 Jülich (Germany); Hildebrandt, E.; Sharath, S. U.; Kurian, J.; Komissinskiy, P.; Alff, L. [Technische Universität Darmstadt, Institute of Materials Science, 64287 Darmstadt (Germany); Szot, K. [Forschungszentrum Jülich GmbH, Peter Grünberg Institute (PGI-7), JARA-FIT, 52425 Jülich (Germany); University of Silesia, A. Chełkowski Institute of Physics, 40-007 Katowice (Poland); Breuer, U. [Forschungszentrum Jülich GmbH, Central Institute for Engineering, Electronics and Analytics (ZEA-3), 52425 Jülich (Germany); Waser, R. [Forschungszentrum Jülich GmbH, Peter Grünberg Institute (PGI-7), JARA-FIT, 52425 Jülich (Germany); RWTH Aachen, Institute of Electronic Materials (IWE 2), 52056 Aachen (Germany)

    2016-06-20

    On highly oxygen deficient thin films of hafnium oxide (hafnia, HfO{sub 2−x}) contaminated with adsorbates of carbon oxides, the formation of hafnium carbide (HfC{sub x}) at the surface during vacuum annealing at temperatures as low as 600 °C is reported. Using X-ray photoelectron spectroscopy the evolution of the HfC{sub x} surface layer related to a transformation from insulating into metallic state is monitored in situ. In contrast, for fully stoichiometric HfO{sub 2} thin films prepared and measured under identical conditions, the formation of HfC{sub x} was not detectable suggesting that the enhanced adsorption of carbon oxides on oxygen deficient films provides a carbon source for the carbide formation. This shows that a high concentration of oxygen vacancies in carbon contaminated hafnia lowers considerably the formation energy of hafnium carbide. Thus, the presence of a sufficient amount of residual carbon in resistive random access memory devices might lead to a similar carbide formation within the conducting filaments due to Joule heating.

  10. SEPARATING HAFNIUM FROM ZIRCONIUM

    Science.gov (United States)

    Lister, B.A.J.; Duncan, J.F.

    1956-08-21

    A dilute aqueous solution of zirconyl chloride which is 1N to 2N in HCl is passed through a column of a cation exchange resin in acid form thereby absorbing both zirconium and associated hafnium impurity in the mesin. The cation exchange material with the absorbate is then eluted with aqueous sulfuric acid of a O.8N to 1.2N strength. The first portion of the eluate contains the zirconium substantially free of hafnium.

  11. Determination of hafnium by atomic absorption spectrometry

    International Nuclear Information System (INIS)

    Yoshida, Isao; Kobayashi, Hiroshi; Ueno, Keihei.

    1977-01-01

    Optimum conditions for atomic absorption spectrophotometric determination of hafnium were investigated by use of a Jarrel-Ash AA-1 instrument which was equipped with a premixed gas burner slotted 50 mm in length and 0.4 mm in width. Absorption of hafnium, which was atomized in an nitrous oxide-acetylene flame, was measured on a resonance line at 307.29 nm. The absorption due to hafnium was enhanced in the presence of ammonium fluoride and iron(III) ion, as shown in Figs. 2 and 3, depending on their concentration. The highest absorption was attained by the addition of (0.15 -- 0.3)M ammonium fluoride, 0.07 M of iron(III) ion and 0.05 M of hydrochloric acid. An excess of the additives decreased the absorption. The presence of zirconium, which caused a significant interference in the ordinary analytical methods, did not affect the absorption due to hafnium, if the zirconium concentration is less than 0.2 M. A standard procedure was proposed; A sample containing a few mg of hafnium was dissolved in a 25-ml volumetric flask, and ammonium fluoride, ferric nitrate and hydrochloric acid were added so that the final concentrations were 0.3, 0.07 and 0.05 M, respectively. Atomic absorption was measured on the aqueous solution in a nitrous oxide-acetylene flame and the hafnium content was calculated from the absorbance. Sensitivity was as high as 12.5 μg of Hf/ml/l% absorption. The present method is especially recommendable to the direct determination of hafnium in samples containing zirconium. (auth.)

  12. New solvent extraction process for zirconium and hafnium

    International Nuclear Information System (INIS)

    Takahashi, M.; Katoh, Y.; Miyazaki, H.

    1984-01-01

    The authors' company developed a new solvent extraction process for zirconium and hafnium separation, and started production of zirconium sponge by this new process in September 1979. The process utilizes selective extraction of zirconium oxysulfate using high-molecular alkyl amine, and has the following advantages: 1. This extraction system has a separation factor as high as 10 to 20 for zirconium and hafnium in the range of suitable acid concentration. 2. In the scrubbing section, removal of all the hafnium that coexists with zirconium in the organic solvent can be effectively accomplished by using scrubbing solution containing hafnium-free zirconium sulfate. Consequently, hafnium in the zirconium sponge obtained is reduced to less than 50 ppm. 3. The extractant undergoes no chemical changes but is very stable for a long period. In particular, its solubility in water is small, about 20 ppm maximum, posing no environmental pollution problems such as are often caused by other process raffinates. At the present time, the zirconium and hafnium separation operation is very stable, and zirconium sponge made by this process can be applied satisfactorily to nuclear reactors

  13. Preparation of hafnium carbide by chemical vapor deposition

    International Nuclear Information System (INIS)

    Hertz, Dominique.

    1974-01-01

    Hard, adhesive coatings of single-phase hafnium carbide were obtained by chemical vapor reaction in an atmosphere containing hafnium tetrachloride, methane and a large excess of hydrogen. By varying the gas phase composition and temperature the zones of formation of the different solid phases were studied and the growth of elementary hafnium and carbon deposits evaluated separately. The results show that the mechanism of hafnium carbide deposition does not hardly involve phenomene of homogeneous-phase methane decomposition or tetrachloride reduction by hydrogen unless the atmosphere is very rich or very poor in methane with respect to tetrachloride. However, hydrogen acting inversely on these two reactions, affects the stoichiometry of the substance deposited. The methane decomposition reaction is fairly slow, the reaction leading to hafnium carbide deposition is faster and that of tetrachloride reduction by hydrogen is quite fast [fr

  14. Assessing hafnium on hafnia as an oxygen getter

    International Nuclear Information System (INIS)

    O'Hara, Andrew; Demkov, Alexander A.; Bersuker, Gennadi

    2014-01-01

    Hafnium dioxide or hafnia is a wide band gap dielectric used in a range of electronic applications from field effect transistors to resistive memory. In many of these applications, it is important to maintain control over oxygen stoichiometry, which can be realized in practice by using a metal layer, specifically hafnium, to getter oxygen from the adjacent dielectric. In this paper, we employ density functional theory to study the thermodynamic stability of an interface between (100)-oriented monoclinic hafnia and hafnium metal. The nudged elastic band method is used to calculate the energy barrier for migration of oxygen from the oxide to the metal. Our investigation shows that the presence of hafnium lowers the formation energy of oxygen vacancies in hafnia, but more importantly the oxidation of hafnium through the migration of oxygen from hafnia is favored energetically

  15. Flotation separation of hafnium(IV) from aqueous solutions

    International Nuclear Information System (INIS)

    Downey, D.M.; Narick, C.N.; Cohen, T.A.

    1985-01-01

    A simple, rapid method for the separation of hafnium from aqueous solutions was investigated using sup(175+181)Hf tracer. Cationic hafnium complex ions were floated from dilute acid solutions with sodium lauryl sulfate (SLS) and anionic hafnium complexes were floated from basic and oxalic acid solutions with hexadecyltrimethyl ammonium bromide (HTMAB). The conditions necessary for quantitative recovery of the metal and mechanisms of flotation are described. (author)

  16. Method of separating hafnium from zirconium

    International Nuclear Information System (INIS)

    Megy, J.A.

    1980-01-01

    English. A new anhydrous method was developed for separating zirconium and hafnium, which gives higher separation factors and is more economical than previous methods. A molten phase, comprising a solution of unseparated zirconium and hafnium and a solvent metal, is first prepared. The molten metal phase is contacted with a fused salt phase which includes a zirconium salt. Zirconium and hafnium separation is effected by mutual displacement with hafnium being transported from the molten metal phase to the fused salt phase, while zirconium is transported from the fused salt phase to the molten metal phase. The solvent metal is less electropositive than zirconium. Zinc was chosen as the solvent metal, from a group which also included cadmium, lead, bismuth, copper, and tin. The fused salt phase cations are more electropositive than zirconium and were selected from a group comprising the alkali elements, the alkaline earth elements, the rare earth elements, and aluminum. A portion of the zirconium in the molten metal phase was oxidized by injecting an oxidizing agent, chlorine, to form zirconium tetrachlorid

  17. Flotation separation of hafnium(IV) from aqueous solutions

    Energy Technology Data Exchange (ETDEWEB)

    Downey, D.M.; Narick, C.N.; Cohen, T.A.

    1985-09-01

    A simple, rapid method for the separation of hafnium from aqueous solutions was investigated using sup(175 + 181)Hf tracer. Cationic hafnium complex ions were floated from dilute acid solutions with sodium lauryl sulfate (SLS) and anionic hafnium complexes were floated from basic and oxalic acid solutions with hexadecyltrimethyl ammonium bromide (HTMAB). The conditions necessary for quantitative recovery of the metal and mechanisms of flotation are described. (author). 21 refs.; 5 figs.

  18. Kinetic studies on the hafnium nad deuterium

    International Nuclear Information System (INIS)

    Bing Wenzeng; Long Xinggui; Zhu Zuliang

    2009-04-01

    Through the method of reaction rate analysis in a constant volume reactor, the time dependence of the pressure drop of the hafnium deuteride formation are studied over a temperature range 573-873 K on a metal hydride thermodynamic and kinetic parameters measuring apparatus. The rate constants of the hafnium deuteride formation, which are 0.0530 s -1 , 0.0452 s -1 , 0.0319 s -1 , 0.0261 s -1 , are calculated at a serial temperatures of 573 K, 673 K, 773 K, 873 K and the initial pressure of 13 kPa. The activation energy of the reaction is (-10.1±1.5) kJ·mol -1 . Comparing the above results with those of titanium deuteride formation on the same measuring apparatus, the kinetic mechanism of the deuteride formation of hafnium and titanium is considered different. It is concluded that the reaction rate of hafnium absorbing deuterium may be controlled by phase transformation and surface oxidation. (authors)

  19. Electronic properties of hafnium oxide: A contribution from defects and traps

    Energy Technology Data Exchange (ETDEWEB)

    Gritsenko, Vladimir A., E-mail: grits@isp.nsc.ru; Perevalov, Timofey V.; Islamov, Damir R., E-mail: damir@isp.nsc.ru

    2016-02-15

    In the present article, we give a review of modern data and latest achievements pertaining to the study of electronic properties of oxygen vacancies in hafnium oxide. Hafnium oxide is a key dielectric for use in many advanced silicon devices. Oxygen vacancies in hafnium oxide largely determine the electronic properties of the material. We show that the electronic transitions between the states due to oxygen vacancies largely determine the optical absorption and luminescent properties of hafnium oxide. We discuss the role of oxygen vacancies as traps that facilitate charge transport in hafnium oxide films. Also, we demonstrate the fact that the electrical conductivity in hafnium oxide is controlled by the phonon-assisted tunnelling of charge carriers between traps that were identified as oxygen vacancies.

  20. Preparation of complexes of zirconium and hafnium tetrachlorides with phosphorus oxychloride

    International Nuclear Information System (INIS)

    McLaughlin, D.F.

    1989-01-01

    This patent describes an improvement in a method for separating hafnium tetrachloride from zirconium tetrachloride where a complex of zirconium-hafnium tetrachlorides and phosphorus oxychloride is prepared from zirconium-hafnium tetrachlorides and the complex of zirconium-hafnium tetrachlorides and phosphorus oxychloride is introduced into a distillation column, which distillation column has a reboiler connected at the bottom and a reflux condenser connected at the top and where a hafnium tetrachloride enriched stream is taken from the top of the column and a zirconium enriched tetrachloride stream is taken from the bottom of the column. The improvement comprising: prepurifying the zirconium-hafnium tetrachlorides, prior to preparation of the complex and introduction of the complex into a distillation column, to substantially eliminate iron chloride from the zirconium hafnium tetrachlorides, whereby buildup or iron chloride in the distillation column and in the reboiler is substantially eliminated and the column can be operated in a continuous, stable and efficient manner

  1. Study of fine structure of deformed hafnium

    International Nuclear Information System (INIS)

    Voskresenskaya, L.A.; Petukhova, A.S.; Kovalev, K.S.

    1978-01-01

    Variations in the hafnium fine structure following the cold plastic deformation have been studied. The fine structure condition has been studied through the harmonic analysis of the profile of the X-ray diffraction line, obtained at the DRON-I installation. Received has been the dependence of the crystal lattice microdistortions value on the deformation extent for hafnium. This dependence is compared with the corresponding one for zirconium. It is found out that at all the deformations the microdistortion distribution is uniform. The microdistortion value grows with the increase in the compression. During the mechanical impact higher microdistortions of the crystal lattice occur in the hafnium rather than in zirconium

  2. Properties of filmogen solutions and films of hafnium compounds

    International Nuclear Information System (INIS)

    Sviridova, A.I.

    1986-01-01

    Study on hafnium hydrolizing compound solutions, used for hafnium oxide homogeneous layer formation, is conducted. In particular, electric conductivity, acidity and refractive index were investigated depending on the sal on ether concentration and the storage time. Oxyhafnium nitrate, hafnium chloride in ethanol, dichlorodiethoxyhafnium, hafnium oxychloride were used as initial compounds. Hydrolysis of hafnium compounds in solution occurs partially; further process occurs in the thin layer on the optical element surface; final decomposition is performed under heat treatment. It is ascertained, that alcoholic-aqueous solutions of inorganic salts can be filmogen only at definite acidity, density and viscosity (1.33-2.5 cp.). It is also ascertained that refractive index values and transmission spectral boundary of coatings, produced from alkoxy compound solutions and from chloride salt solutions, are practically the same. Transmittance boundary in ultraviolet region of spectrum of oxide films produced from nitrate and chloride solutions, varies with the heating temperature increase differently

  3. Investigation of ferromagnetism in oxygen deficient hafnium oxide thin films

    Energy Technology Data Exchange (ETDEWEB)

    Hildebrandt, Erwin; Kurian, Jose; Krockenberger, Yoshiharu; Alff, Lambert [Institut fuer Materialwissenschaft, TU Darmstadt (Germany); Suter, Andreas [PSI, Villingen (Switzerland); Wilhelm, Fabrice; Rogalev, Andrei [ESRF, Grenoble (France)

    2008-07-01

    Oxygen deficient thin films of hafnium oxide were grown on single crystal r-cut and c-cut sapphire by reactive molecular beam epitaxy. RF-activated oxygen was used for the in situ oxidation of hafnium oxide thin films. Oxidation conditions were varied substantially in order to create oxygen deficiency in hafnium oxide films intentionally. The films were characterized by X-ray and magnetic measurements. X-ray diffraction studies show an increase in lattice parameter with increasing oxygen deficiency. Oxygen deficient hafnium oxide thin films also showed a decreasing bandgap with increase in oxygen deficiency. The magnetisation studies carried out with SQUID did not show any sign of ferromagnetism in the whole oxygen deficiency range. X-ray magnetic circular dichroism measurements also confirmed the absence of ferromagnetism in oxygen deficient hafnium oxide thin films.

  4. Titanium zirconium and hafnium coordination compounds with vanillin thiosemicarbazone

    International Nuclear Information System (INIS)

    Konunova, Ts.B.; Kudritskaya, S.A.

    1987-01-01

    Coordination compounds of titanium zirconium and hafnium tetrachlorides with vanillin thiosemicarbazone of MCl 4 x nLig composition, where n=1.5, 4 for titanium and 1, 2, 4 for zirconium and hafnium, are synthesized. Molar conductivity of ethanol solutions is measured; IR spectroscopic and thermochemical investigation are carried out. The supposition about ligand coordination via sulfur and azomethine nitrogen atoms is made. In all cases hafnium forms stable compounds than zirconium

  5. Hafnium - material for chemical apparatus engineering

    International Nuclear Information System (INIS)

    Jennert, D.

    1981-01-01

    This work describes - on the background of available literature - the properties of hafnium in technical quality (DIN-material No. 2.6400) as material for chemical apparatus engineering. The occurence, refining, physical and chemical properties will be described as well as the material behavior. In conclusion, it has been found that there is, at present, sufficient information for the engineering of hafnium which has to be completed by additional investigations for special applications. (orig.) [de

  6. Internal Dosimetry for Inhalation of Hafnium Tritide Aerosols

    Energy Technology Data Exchange (ETDEWEB)

    Inkret, W.C.T.; Schillaci, M.E.; Boyce, M.K.; Cheng, Y.S.; Efurd, D.W.; Little, T.T.; Miller, G.; Musgrave, J.A.; Wermer, J.R

    2001-07-01

    Metal tritides with low dissolution rates may have residence times in the lungs which are considerably longer than the biological half-time normally associated with tritium in body water, resulting in long-term irradiation of the lungs by low energy {beta} particles and bremsstrahlung X rays. Samples of hafnium tritide were placed in a lung simulant fluid to determine approximate lung dissolution rates. Hafnium hydride samples were analysed for particle size distribution with a scanning electron microscope. Lung simulant data indicated a biological dissolution half-time for hafnium tritide on the order of 10{sup 5}d. Hafnium hydride particle sizes ranged between 2 and 10 {mu}m, corresponding to activity median aerodynamic diameters of 5 to 25 {mu}m. Review of in vitro dissolution data, development of a biokinetic model, and determination of secondary limits for 1 {mu}m AMAD particles are presented and discussed. (author)

  7. Titanium(IV), zirconium, hafnium and thorium

    International Nuclear Information System (INIS)

    Brown, Paul L.; Ekberg, Christian

    2016-01-01

    Titanium can exist in solution in a number of oxidation states. The titanium(IV) exists in acidic solutions as the oxo-cation, TiO 2+ , rather than Ti 4+ . Zirconium is used in the ceramics industry and in nuclear industry as a cladding material in reactors where its reactivity towards hydrolysis reactions and precipitation of oxides may result in degradation of the cladding. In nature, hafnium is found together with zirconium and as a consequence of the contraction in ionic radii that occurs due to the 4f -electron shell, the ionic radius of hafnium is almost identical to that of zirconium. All isotopes of thorium are radioactive and, as a consequence of it being fertile, thorium is important in the nuclear fuel cycle. The polymeric hydrolysis species that have been reported for thorium are somewhat different to those identified for zirconium and hafnium, although thorium does form the Th 4 (OH) 8 8+ species.

  8. Ferroelectricity in undoped hafnium oxide

    International Nuclear Information System (INIS)

    Polakowski, Patrick; Müller, Johannes

    2015-01-01

    We report the observation of ferroelectric characteristics in undoped hafnium oxide thin films in a thickness range of 4–20 nm. The undoped films were fabricated using atomic layer deposition (ALD) and embedded into titanium nitride based metal-insulator-metal (MIM) capacitors for electrical evaluation. Structural as well as electrical evidence for the appearance of a ferroelectric phase in pure hafnium oxide was collected with respect to film thickness and thermal budget applied during titanium nitride electrode formation. Using grazing incidence X-Ray diffraction (GIXRD) analysis, we observed an enhanced suppression of the monoclinic phase fraction in favor of an orthorhombic, potentially, ferroelectric phase with decreasing thickness/grain size and for a titanium nitride electrode formation below crystallization temperature. The electrical presence of ferroelectricity was confirmed using polarization measurements. A remanent polarization P r of up to 10 μC cm −2 as well as a read/write endurance of 1.6 × 10 5 cycles was measured for the pure oxide. The experimental results reported here strongly support the intrinsic nature of the ferroelectric phase in hafnium oxide and expand its applicability beyond the doped systems

  9. Hafnium-Based Contrast Agents for X-ray Computed Tomography.

    Science.gov (United States)

    Berger, Markus; Bauser, Marcus; Frenzel, Thomas; Hilger, Christoph Stephan; Jost, Gregor; Lauria, Silvia; Morgenstern, Bernd; Neis, Christian; Pietsch, Hubertus; Sülzle, Detlev; Hegetschweiler, Kaspar

    2017-05-15

    Heavy-metal-based contrast agents (CAs) offer enhanced X-ray absorption for X-ray computed tomography (CT) compared to the currently used iodinated CAs. We report the discovery of new lanthanide and hafnium azainositol complexes and their optimization with respect to high water solubility and stability. Our efforts culminated in the synthesis of BAY-576, an uncharged hafnium complex with 3:2 stoichiometry and broken complex symmetry. The superior properties of this asymmetrically substituted hafnium CA were demonstrated by a CT angiography study in rabbits that revealed excellent signal contrast enhancement.

  10. 40 CFR 471.90 - Applicability; description of the zirconium-hafnium forming subcategory.

    Science.gov (United States)

    2010-07-01

    ... zirconium-hafnium forming subcategory. 471.90 Section 471.90 Protection of Environment ENVIRONMENTAL... POINT SOURCE CATEGORY Zirconium-Hafnium Forming Subcategory § 471.90 Applicability; description of the zirconium-hafnium forming subcategory. This subpart applies to discharges of pollutants to waters of the...

  11. Calorimetric measurements on hafnium titanate

    International Nuclear Information System (INIS)

    Kandan, R.; Prabhakara Reddy, B.; Panneerselvam, G.; Nagarajan, K.

    2012-01-01

    Owing to its desirable nuclear and mechanical properties such as good absorption cross-section for thermal neutrons (105 barns), hafnium titanate (HfTiO 4 ) finds application as control rods for nuclear reactors. An accurate knowledge of the thermo physical properties of this material is necessary for design of control rod and for modeling its performance. Heat capacity is an important thermodynamic property that determines the temperature dependent variation of all other thermodynamic properties. Hence enthalpy increments of hafnium titanate (HfTiO 4 ) were measured in the temperature range 803-1663 K by employing the method of inverse drop calorimetry using high temperature differential calorimeter

  12. Preparation of complexes of zirconium and hafnium tetrachlorides with phosphorus oxychloride

    International Nuclear Information System (INIS)

    Snyder, T.S.; Stoltz, R.A.

    1989-01-01

    This patent describes an improvement in a method for separating hafnium chloride from zirconium chloride using a distillation column, with a hafnium chloride enriched vapor stream taken from the top of the column and a zirconium enriched chloride stream taken from the bottom of the column. The improvement comprising: purifying the zirconium-hafnium chloride in a molten salt purification vessel prior to or after introduction into the distillation column to substantially eliminate iron chloride from the zirconium-hafnium chloride by at least periodically removing iron chloride from the molten salt purification vessel by electrochemically plating iron onto an electrode in the molten salt purification vessel. The molten salt in the molten salt purification vessel consisting essentially of a mixture of chlorides selected from the group consisting of alkali metals, alkaline earth metals, zirconium, hafnium, aluminum, manganese, and zinc

  13. Method of purifying zirconium tetrachloride and hafnium tetrachloride in a vapor stream

    International Nuclear Information System (INIS)

    Snyder, T.S.; Stolz, R.A.

    1992-01-01

    This patent describes a method of purifying zirconium tetrachloride and hafnium tetrachloride in a vapor stream from a sand chlorinator in which the silicon and metals present in sand fed to the chlorinator are converted to chlorides at temperatures over about 800 degrees C. It comprises cooling a vapor stream from a sand chlorinator, the vapor stream containing principally silicon tetrachloride, zirconium tetrachloride, and hafnium tetrachloride contaminated with ferric chloride, to a temperature of from about 335 degrees C to about 600 degrees C; flowing the vapor stream through a gaseous diffusion separative barrier to produce a silicon tetrachloride-containing vapor stream concentrated in zirconium tetrachloride and hafnium tetrachloride and a silicon tetrachloride-containing vapor stream depleted in zirconium tetrachloride and hafnium tetrachloride; adsorbing the ferric chloride in the separative barrier; and recovering the silicon tetrachloride stream concentrated in zirconium tetrachloride and hafnium tetrachloride separately from the silicon tetrachloride stream depleted in zirconium tetrachloride and hafnium tetrachloride

  14. Spectrofluorimetric determination of hafnium and zirconium with 3,7-dihydroxyflavone

    Energy Technology Data Exchange (ETDEWEB)

    Ito, Takushi; Suzuki, Osamu; Seuzuki, Tetsuo; Murata, Akira

    1986-04-01

    The absorptive and fluorescent characteristics of the hafnium and zirconium complexes of 3-hydroxyflavone and its 12 hydroxy and methoxy derivatives have been studied. The fluorescence of the 1:1 hafnium - 3,7-dihydroxyflavone complex (lambdasub(ex.)397 nm,lambdasub(em.) 465 nm) in 3 M hydrochloric acid has been used to determine 2-40 ng ml/sup -1/ of hafnium. The fluorescence of the 1:1 zirconium - 3,7-dihydroxyflavone complex (lambdasub(ex.) 395 nm, lambda sub(em.) 465 nm) at pH 2.0 in 0.02 M sulphate solution has been used to determine 2-40 ng ml/sup -1/ of zirconium. These methods are very sensitive and can be used for the simultaneous determination of hafnium and zirconium with an error of about 5%.

  15. Molten salt extractive distillation process for zirconium-hafnium separation

    International Nuclear Information System (INIS)

    McLaughlin, D.F.; Stoltz, R.A.

    1989-01-01

    This patent describes an improvement in a process for zirconium-hafnium separation. It utilizes an extractive distillation column with a mixture of zirconium and hafnium tetrachlorides introduced into a distillation column having a top and bottom with hafnium enriched overheads taken from the top of the column and a molten salt solvent circulated through the column to provide a liquid phase, and with molten salt solvent containing zirconium chloride being taken from the bottom of the distillation column. The improvements comprising: utilizing a molten salt solvent consisting principally of lithium chloride and at least one of sodium, potassium, magnesium and calcium chlorides; stripping of the zirconium chloride taken from the bottom of the distillation column by electrochemically reducing zirconium from the molten salt solvent; and utilizing a pressurized reflux condenser on the top of the column to add the hafnium chloride enriched overheads to the molten salt solvent previously stripped of zirconium chloride

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

    Science.gov (United States)

    2010-07-01

    ... primary zirconium and hafnium subcategory. 421.330 Section 421.330 Protection of Environment ENVIRONMENTAL... CATEGORY Primary Zirconium and Hafnium Subcategory § 421.330 Applicability: Description of the primary zirconium and hafnium subcategory. The provisions of this subpart are applicable to discharges resulting...

  17. Design and fabrication of hafnium tube to control the power of the irradiation test fuel in HANARO

    Energy Technology Data Exchange (ETDEWEB)

    Kim, D. H.; Lee, C. B.; Kim, Y. M.; Yang, Y. S.; Jung, Y. H

    2003-05-01

    For the irradiation test at HANARO, non-instrumentation capsule was manufactured and hafnium tube was used to control LHGR of HANARO. Hafnium tube can control the irradiation condition of HANARO similar to that of commercial reactor. Hafnium tube thickness was determined by the LHGR calculated at OR-4 irradiation hole to be installed the non-instrumented capsule. To fabricate the hafnium tube with hafnium plate, the fabrication method was determined by using the hafnium mechanical properties. And the tensile strength of hafnium was confirmed by tensile test. This report is confirmed the LHGR control at the OR-4 and the Hafnium fabrication for in used which the AFPCAP non-instrumented irradiation capsule.

  18. Use of X-ray fluorescence analysis for the determination of hafnium in zircalloys

    International Nuclear Information System (INIS)

    Sato, I.M.; Salvador, V.L.R.; Lordello, A.R.

    1985-01-01

    The determination of hafnium at trace levels (ppm) in the presence of zirconium by X-ray fluorescence technique is presented. The samples were prepared in the form of double-layer pellets, with boric acid as the binding material. The most sensitive first order line of hafnium HfLα (0.157 nm), which is used analyticaly, has approximately 67% overlapping with second order line of zirconium ZrKα 1 , (0.079 nm). As the excitation potencial of zirconium is larger than hafnium, the best condition was selected, so that the interference of zirconium intensity would not be significant in hafnium analytical line. The method allowed the determination of hafnium above 5.0 ppm (LLd = 1.5 ppm) with an accuracy of less than 10%. (Author) [pt

  19. Use of hafnium in control bars of nuclear reactors

    International Nuclear Information System (INIS)

    Ramirez S, J.R.; Alonso V, G.

    2003-01-01

    Recently the use of hafnium as neutron absorber material in nuclear reactors has been reason of investigation by virtue of that this material has nuclear properties as to the neutrons absorption and structural that can prolong the useful life of the control mechanisms of the nuclear reactors. In this work some of those more significant hafnium properties are presented like nuclear material. Also there are presented calculations carried out with the HELIOS code for fuel cells of uranium oxide and of uranium and plutonium mixed oxides under controlled conditions with conventional bars of boron carbide and also with similar bars to which are substituted the absorbent material by metallic hafnium, the results are presented in this work. (Author)

  20. The corrosion behavior of hafnium in high-temperature-water environments

    Energy Technology Data Exchange (ETDEWEB)

    Rishel, D.M.; Smee, J.D.; Kammenzind, B.F.

    1999-10-01

    The high-temperature-water corrosion performance of hafnium is evaluated. Corrosion kinetic data are used to develop correlations that are a function of time and temperature. The evaluation is based on corrosion tests conducted in out-of-pile autoclaves and in out-of-flux locations of the Advanced Test Reactor (ATR) at temperatures ranging from 288 to 360 C. Similar to the corrosion behavior of unalloyed zirconium, the high-temperature-water corrosion response of hafnium exhibits three corrosion regimes: pretransition, posttransition, and spalling. In the pretransition regime, cubic corrosion kinetics are exhibited, whereas in the posttransition regime, linear corrosion kinetics are exhibited. Because of the scatter in the spalling regime data, it is not reasonable to use a best fit of the data to describe spalling regime corrosion. Data also show that neutron irradiation does not alter the corrosion performance of hafnium. Finally, the data illustrate that the corrosion rate of hafnium is significantly less than that of Zircaloy-2 and Zircaloy-4.

  1. Corrosion potentials of hafnium in molten alkaline-earth metal chlorides

    International Nuclear Information System (INIS)

    Kovalik, O.Yu.; Tkhaj, V.D.

    2000-01-01

    Corrosion potentials of hafnium in molten calcium, strontium and barium chlorides are measured and their temperature dependences are determined. It is stated that the corrosion potential of hafnium becomes more electropositive with an increase of the environment temperature. If the temperature is the same the potential shifts to the interval of more electronegative values in the row of CaCl 2 , SrCl 2 , BaCl 2 which corresponds to a lesser corrosion rate in environments positioned from left to right. the comparison of hafnium corrosion potentials with previously measured values for titanium and zirconium shows that a metal activity decrease results in a more electronegative corrosion potential [ru

  2. Electronic structure of pentacene on hafnium studied by ultraviolet photoelectron spectroscopy

    International Nuclear Information System (INIS)

    Kang, Seong Jun; Yi, Yeon Jin; Kim, Chung Yi; Whang, Chung Nam

    2005-01-01

    The electronic structure of pentacene on hafnium, which is a low work function metal, was analyzed by using ultraviolet photoelectron spectroscopy. The energy level alignment was studied by using the onset of the highest occupied molecular orbital level and the shift of the vacuum level of the pentacene layer, which was deposited on a clean hafnium surface in a stepwise manner. The measured onset of the highest occupied molecular orbital energy level was 1.52 eV from the Fermi level of hafnium. The vacuum level was shifted 0.28 eV toward higher binding energy with additional pentacene layers, which means an interfacial dipole exists at the interface between pentacene and hafnium. We confirm that a small electron injection barrier can be achieved by inserting a low work function metal in a pentacene thin-film transistor.

  3. Synthesis of Hafnium-Based Ceramic Materials for Ultra-High Temperature Aerospace Applications

    Science.gov (United States)

    Johnson, Sylvia; Feldman, Jay

    2004-01-01

    This project involved the synthesis of hafnium (Hf)-based ceramic powders and Hf-based precursor solutions that were suitable for preparation of Hf-based ceramics. The Hf-based ceramic materials of interest in this project were hafnium carbide (with nominal composition HE) and hafnium dioxide (HfO2). The materials were prepared at Georgia Institute of Technology and then supplied to research collaborators Dr. Sylvia Johnson and Dr. Jay Feldman) at NASA Ames Research Center.

  4. Application of hafnium hydride control rod to large sodium cooled fast breeder reactor

    Energy Technology Data Exchange (ETDEWEB)

    Ikeda, Kazumi, E-mail: kazumi_ikeda@mfbr.mhi.co.jp [Mitsubishi FBR Systems, Inc., 34-17, Jingumae 2-Chome, Shibuya-ku, Tokyo 150-0001 (Japan); Moriwaki, Hiroyuki, E-mail: hiroyuki_moriwaki@mfbr.mhi.co.jp [Mitsubishi FBR Systems, Inc., 34-17, Jingumae 2-Chome, Shibuya-ku, Tokyo 150-0001 (Japan); Ohkubo, Yoshiyuki, E-mail: yoshiyuki_okubo@mfbr.mhi.co.jp [Mitsubishi FBR Systems, Inc., 34-17, Jingumae 2-Chome, Shibuya-ku, Tokyo 150-0001 (Japan); Iwasaki, Tomohiko, E-mail: tomohiko.iwasaki@qse.tohoku.ac.jp [Department of Quantum Science and Energy Engineering, Tohoku University, Aoba, Aramaki, Aoba-ku, Sendai-shi, Miyagi-ken 980-8579 (Japan); Konashi, Kenji, E-mail: konashi@imr.tohoku.ac.jp [Institute for Materials Research, Tohoku University, Narita-cho, Oarai-machi, Higashi-Ibaraki-gun, Ibaraki-ken 311-1313 (Japan)

    2014-10-15

    Highlights: • Application of hafnium hydride control rod to large sodium cooled fast breeder reactor. • This paper treats application of an innovative hafnium hydride control rod to a large sodium cooled fast breeder reactor. • Hydrogen absorption triples the reactivity worth by neutron spectrum shift at H/Hf ratio of 1.3. • Lifetime of the control rod quadruples because produced daughters of hafnium isotopes are absorbers. • Nuclear and thermal hydraulic characteristics of the reactor are as good as or better than B-10 enriched boron carbide. - Abstract: This study treats the feasibility of long-lived hafnium hydride control rod in a large sodium-cooled fast breeder reactor by nuclear and thermal analyses. According to the nuclear calculations, it is found that hydrogen absorption of hafnium triples the reactivity by the neutron spectrum shift at the H/Hf ratio of 1.3, and a hafnium transmutation mechanism that produced daughters are absorbers quadruples the lifetime due to a low incineration rate of absorbing nuclides under irradiation. That is to say, the control rod can function well for a long time because an irradiation of 2400 EFPD reduces the reactivity by only 4%. The calculation also reveals that the hafnium hydride control rod can apply to the reactor in that nuclear and thermal characteristics become as good as or better than 80% B-10 enriched boron carbide. For example, the maximum linear heat rate becomes 3% lower. Owing to the better power distribution, the required flow rate decreases approximately by 1%. Consequently, it is concluded on desk analyses that the long lived hafnium hydride control rod is feasible in the large sodium-cooled fast breeder reactor.

  5. X-Ray Photoemission Study of the Oxidation of Hafnium

    International Nuclear Information System (INIS)

    Chourasia, R.; Hickman, J.L.; Miller, R.L.; Nixon, G.A.; Seabolt, M.A.

    2011-01-01

    About 20 angstrom of hafnium were deposited on silicon substrates using the electron beam evaporation technique. Two types of samples were investigated. In one type, the substrate was kept at the ambient temperature. After the deposition, the substrate temperature was increased to 100, 200, and 300 degree C. In the other type, the substrate temperature was held fixed at some value during the deposition. For this type, the substrate temperatures used were 100, 200, 300, 400, 500, 550, and 600 degree C. The samples were characterized in situ by the technique of X-ray photoelectron spectroscopy. No trace of elemental hafnium is observed in the deposited overlayer. Also, there is no evidence of any chemical reactivity between the overlayer and the silicon substrate over the temperature range used. The hafnium overlayer shows a mixture of the dioxide and the suboxide. The ratio of the suboxide to dioxide is observed to be more in the first type of samples. The spectral data indicate that hafnium has a strong affinity for oxygen. The overlayer gets completely oxidized to form HfO 2 at substrate temperature around 300 degree C for the first type of samples and at substrate temperature greater than 550 degree C for the second type

  6. X-Ray Photoemission Study of the Oxidation of Hafnium

    Directory of Open Access Journals (Sweden)

    A. R. Chourasia

    2009-01-01

    Full Text Available About 20 Å of hafnium were deposited on silicon substrates using the electron beam evaporation technique. Two types of samples were investigated. In one type, the substrate was kept at the ambient temperature. After the deposition, the substrate temperature was increased to 100, 200, and 300∘C. In the other type, the substrate temperature was held fixed at some value during the deposition. For this type, the substrate temperatures used were 100, 200, 300, 400, 500, 550, and 600∘C. The samples were characterized in situ by the technique of X-ray photoelectron spectroscopy. No trace of elemental hafnium is observed in the deposited overlayer. Also, there is no evidence of any chemical reactivity between the overlayer and the silicon substrate over the temperature range used. The hafnium overlayer shows a mixture of the dioxide and the suboxide. The ratio of the suboxide to dioxide is observed to be more in the first type of samples. The spectral data indicate that hafnium has a strong affinity for oxygen. The overlayer gets completely oxidized to form HfO2 at substrate temperature around 300∘C for the first type of samples and at substrate temperature greater than 550∘C for the second type.

  7. High temperature diffusion of hafnium in tungsten and a tungsten-hafnium carbide alloy

    International Nuclear Information System (INIS)

    Ozaki, Y.; Zee, R.H.

    1994-01-01

    Refractory metals and ceramics are used extensively in energy systems due to their high temperature properties. This is particularly important in direct conversion systems where thermal to electric conversion efficiency is a direct function of temperature. Tungsten, which has the highest melting temperature among elemental metals, does not possess sufficient creep resistance at temperature above 1,600 K. Different dispersion strengthened tungsten alloys have been developed to extend the usefulness of tungsten to higher temperatures. One of these alloys, tungsten with 0.4 mole percent of finely dispersed HfC particles (W-HfC), has the optimum properties for high temperature applications. Hafnium carbide is used as the strengthening agent due to its high chemical stability and its compatibility with tungsten. The presence of HfC particles retards the rate of grain growth as well as restricting dislocation motion. Both of which are beneficial for creep resistance. The long term behavior of this alloy depends largely on the evolution of its microstructure which is governed by the diffusion of its constituents. Data on the diffusion of carbon in tungsten and tungsten self-diffusion are available, but no direct measurements have been made on the diffusion of hafnium in tungsten. The only diffusion data available are estimated from a coarsening study and these data are highly unreliable. In this study, the diffusion behavior of hafnium in pure tungsten and in a W-HfC alloy was directly measured by means of Secondary Ion Mass Spectroscopy (SIMS). The selection of the W-HfC alloy is due to its importance in high temperature engineering applications, and its higher recrystallization temperature. The presence of HfC particles in tungsten restricts grain growth resulting in better high temperature creep resistance. The higher recrystallization temperature allows measurements to be made over a wider range of temperatures at a relatively constant grain size

  8. Elaboration and characterisation of yttrium oxide and hafnium oxide powders by the sol-gel process

    International Nuclear Information System (INIS)

    Hours, T.

    1988-01-01

    The two classical sol-gel processes, colloidal and polymeric are studied for the preparation of yttrium oxide and hafnium oxide high performance powders. In the colloidal process, controlled and reproducible conditions for the preparation of yttrium oxide and hafnium oxide sols from salts or alkoxides are developed and the hydrothermal synthesis monodisperse hafnium oxide colloids is studied. The polymeric process is studied with hafnium ethyl-hexylate, hydrolysis kinetics for controlled preparation of sols and gels is investigated. Each step of preparation is detailed and powders obtained are characterized [fr

  9. Modelling of Zirconium and Hafnium separation using continuous annular chromatography

    International Nuclear Information System (INIS)

    Moch-Setyadji; Endang Susiantini

    2014-01-01

    Nuclear degrees of zirconium in the form of a metal alloy is the main material for fuel cladding of NPP. Zirconium is also used as sheathing UO 2 kernel in the form of ZrC as a substitute of SiC in the fuel elements of High Temperature Reactor (HTR). Difficulty separating hafnium from zirconium because it has a lot of similarities in the chemical properties of Zr and Hf. Annular chromatography is a device that can be used for separating of zirconium and hafnium to obtain zirconium nuclear grade. Therefore, it is necessary to construct the mathematical modelling that can describe the separation of zirconium and hafnium in the annular chromatography containing anion resin dowex-1X8. The aim of research is to perform separation simulation by using the equilibrium model and mass transfer coefficient resulted from research. Zr and Hf feed used in this research were 26 and 1 g/l, respectively. Height of resin (L), angular velocity (ω) and the superficial flow rate (uz) was varied to determine the effect of each parameter on the separation of Zr and Hf. By using Kd and Dv values resulted previous research. Simulation results showed that zirconium and hafnium can be separated using a continuous annular chromatography with high resin (long bed) 50 cm, superficial flow rate of 0.001 cm/s, the rotation speed of 0.006 rad/min and 20 cm diameter annular. In these conditions the results obtained zirconium concentration of 10,303.226 g/m 3 and hafnium concentration of 12.324 g/m 3 (ppm). (author)

  10. Joint titrimetric determination of zirconium and hafnium

    International Nuclear Information System (INIS)

    Vazquez, Cristina; Botbol, Moises; Bianco de Salas, G.N.; Cornell de Casas, M.I.

    1980-01-01

    A method for the joint titrimetric determination of zirconium and hafnium, which are elements of similar chemical behaviour, is described. The disodic salt of the ethylendiaminetetracetic acid (EDTA) is used for titration, while xilenol orange serves as final point indicator. Prior to titration it is important to evaporate with sulfuric acid, the solution resulting from the zirconium depolymerization process, to adjust the acidity and to eliminate any interferences. The method, that allows the quick and precise determination of zirconium and hafnium in quantities comprised between 0.01 and mg, was applied to the analysis of raw materials and of intermediate and final products in the fabrication of zirconium sponge and zircaloy. (M.E.L.) [es

  11. Compositional characterization of hafnium alloy used as control rod material in nuclear reactor

    International Nuclear Information System (INIS)

    Sharma, P.K.; Bassan, M.K.T.; Avhad, D.K.; Singhal, R.K.

    2014-01-01

    Hafnium (Hf) is a heavy, steel-gray metal in the reactive metals group that is very closely related to zirconium (Zr) and forms a continuous solid-solution at all concentrations of zirconium and hafnium. Hafnium occurs naturally with zirconium at a ratio of approximately 1:50 and is produced exclusively as a co-product of nuclear-grade zirconium. It is used in a variety of applications where few substitutes are available. Thus with its relatively high thermal neutron absorption cross-section, hafnium's biggest application is as control rod material in nuclear reactors. During this work, major (Zirconium (Zr), Cobalt (Co) and Molybdenum (Mo)) and trace ((Iron (Fe), Nickel (Ni) and Titanium (Ti)) elements were measured in the bulk matrices of Hf. These materials are also associated with other impurities such as O, N, H etc.

  12. Bond formation in hafnium atom implantation into SiC induced by high-energy electron irradiation

    International Nuclear Information System (INIS)

    Yasuda, H.; Mori, H.; Sakata, T.; Naka, M.; Fujita, H.

    1992-01-01

    Bilayer films of Hf (target atoms)/α-SiC (substrate) were irradiated with 2 MeV electrons in an ultra-high voltage electron microscope (UHVEM), with the electron beam incident on the hafnium layer. As a result of the irradiation, hafnium atoms were implanted into the SiC substrate. Changes in the microstructure and valence electronic states associated with the implantation were studied by a combination of UHVEM and Auger valence electron spectroscopy. The implantation process is summarized as follows. (1) Irradiation with 2 MeV electrons first induces a crystalline-to-amorphous transition in α-SiC. (2) Hafnium atoms which have been knocked-off from the hafnium layer by collision with the 2 MeV electrons are implanted into the resultant amorphous SiC. (3) The implanted hafnium atoms make preferential bonding to carbon atoms. (4) With continued irradiation, the hafnium atoms repeat the displacement along the beam direction and the subsequent bonding with the dangling hybrids of carbon and silicon. The repetition of the displacement and subsequent bonding lead to the deep implantation of hafnium atoms into the SiC substrate. It is concluded that implantation successfully occurs when the bond strength between a constituent atom of a substrate and an injected atom is stronger than that between constituent atoms of a substrate. (Author)

  13. Hafnium Resonance Parameter Analysis Using Neutron Capture and Transmission Experiments

    International Nuclear Information System (INIS)

    MJ Trbovich; DP Barry; RE Slovacck; Y Danon; RC Block; JA Burke; NJ Drindak; G Leinweber; RV Ballad

    2004-01-01

    The focus of this work is to determine resonance parameters for stable hafnium isotopes in the 0.005-200 eV region, with special emphasis on the overlapping 176 Hf and 178 Hf resonances near 8 eV. The large neutron cross section of hafnium, combined with its corrosion resistance and excellent mechanical properties, make it a useful material for controlling nuclear reactions. Experiments measuring neutron capture and transmission were performed at the Rensselaer Polytechnic Institute (RPI) electron linear accelerator (LINAC) using the time of flight method. 6 Li glass scintillation detectors were used for transmission experiments at flight path lengths of 15 and 25 m. Capture experiments were done using a sixteen section NaI(Tl) multiplicity detector at a flight path length of 25 m. These experiments utilized various thicknesses of metallic and isotopically-enriched liquid samples. The liquid samples were designed to provide information on the 176 Hf and 178 Hf contributions to the 8 eV doublet without saturation. Data analysis was done using the R-matrix Bayesian code SAMMY version M6 beta. SAMMY is able to account for experimental resolution effects for each of the experimental setups at the RPI LINAC, and also can correct for multiple scattering effects in neutron capture yield data. The combined capture and transmission data analysis yielded resonance parameters for all hafnium isotopes from 0.005-200 eV. Resonance integrals were calculated along with errors for each hafnium isotope using the NJOY [1] and INTER [2] codes. The isotopic resonance integrals calculated were significantly different than previously published values; however the calculated elemental hafnium resonance integral changed very little

  14. Zirconium and hafnium in the southeastern Atlantic States

    Science.gov (United States)

    Mertie, J.B.

    1958-01-01

    The principal source of zirconium and hafnium is zircon, though a minor source is baddeleyite, mined only in Brazil. Zircon is an accessory mineral in igneous, metamorphic, and sedimentary rocks, but rarely occurs in hardrock in minable quantities. The principal sources of zircon are therefore alluvial deposits, which are mined in many countries of five continents. The principal commercial deposits in the United States are in Florida, though others exist elsewhere in the southeastern Coastal Plain. The evidence indicates that conditions for the accumulation of workable deposits of heavy minerals were more favorable during the interglacial stages of the Pleistocene epoch than during Recent time. Therefore detrital ores of large volume and high tenor are more likely to be found in the terrace deposits than along the present beaches. Other concentrations of heavy minerals, however, are possible at favored sites close to the Fall Line where the Tuscaloosa formation rests upon the crystalline rocks of the Piedmont province. A score of heavy and semiheavy minerals occur in the detrital deposits of Florida, but the principal salable minerals are ilmenite, leucoxene, rutile, and zircon, though monazite and staurolite are saved at some mining plants. Commercial deposits of heavy minerals are generally required to have a tenor of 4 percent, though ores with a lower tenor can be mined at a profit if the content of monazite is notably high. The percentages of zircon in the concentrates ranges from 10 to 16 percent, and in eastern Florida from 13 to 15 percent. Thus the tenor in zircon of the ore-bearing sands ranges from 0.4 to 0.6 percent. The content of hafnium in zircon is immaterial for many uses, but for some purposes very high or very low tenors in hafnium are required. Alluvial zircon cannot be separated into such varieties, which, if needed, must be obtained from sources in bedrock. It thus becomes necessary to determine the Hf : Zr ratios in zircon from many kinds of

  15. Niobium and hafnium grown on porous membranes

    International Nuclear Information System (INIS)

    Morant, C.; Marquez, F.; Campo, T.; Sanz, J.M.; Elizalde, E.

    2010-01-01

    In this work we report on a method for fabricating highly ordered nanostructures of niobium and hafnium metals by physical vapour deposition using two different templates: anodized aluminum oxide membranes (AAO) and zirconium onto AAO membranes (Zr/AAO). The growth mechanism of these metal nanostructures is clearly different depending on the material used as a template. A different morphology was obtained by using AAO or Zr/AAO templates: when the metal is deposited onto AAO membranes, nanospheres with ordered hexagonal regularity are obtained; however, when the metal is deposited onto a Zr/AAO template, highly ordered nanocones are formed. The experimental approach described in this work is simple and suitable for synthesizing nanospheres or nanoholes of niobium and hafnium metals in a highly ordered structure.

  16. Analytical study of zirconium and hafnium α-hydroxy carboxylates

    International Nuclear Information System (INIS)

    Terra, V.R.

    1991-01-01

    The analytical study of zirconium and hafnium α-hydroxy carboxylates was described. For this purpose dl-mandelic, dl-p-bromo mandelic, dl-2-naphthyl glycolic, and benzilic acids were prepared. These were used in conjunction with glycolic, dl-lactic, dl-2-hydroxy isovaleric, dl-2-hydroxy hexanoic, and dl-2-hydroxy dodecanoic acids in order to synthesize the zirconium(IV) and hafnium(IV) tetrakis(α-hydroxy carboxylates). The compounds were characterized by melting point determination, infrared spectroscopy, thermogravimetric analysis, calcination to oxides and X-ray diffractometry by the powder method. (C.G.C)

  17. High temperature evaporation of titanium, zirconium and hafnium carbides

    International Nuclear Information System (INIS)

    Gusev, A.I.; Rempel', A.A.

    1991-01-01

    Evaporation of cubic nonstoichiometric carbides of titanium, zirconium and hafnium in a comparatively low-temperature interval (1800-2700) with detailed crystallochemical sample certification is studied. Titanium carbide is characterized by the maximum evaporation rate: at T>2300 K it loses 3% of sample mass during an hour and at T>2400 K titanium carbide evaporation becomes extremely rapid. Zirconium and hafnium carbide evaporation rates are several times lower than titanium carbide evaporation rates at similar temperatures. Partial pressures of metals and carbon over the carbides studied are calculated on the base of evaporation rates

  18. Determination of hafnium, molybdenum, and vanadium in niobium and niobium-based alloys by atomic absorption spectrometry

    International Nuclear Information System (INIS)

    Ide, Kunikazu; Kobayashi, Takeshi; Sudo, Emiko.

    1985-01-01

    The analytical procedure is as follows: Weigh 1 g of a sample and put it into a 100 cm 3 PTFE beaker. Add 5 ml of distilled water and 5 ml of hydrofluoric acid, and then heat the solution on a hot plate, adding 3 ml of nitric acid dropwise. Dilute the solution to 100 cm 3 with distilled water. When hafnium is determined, add 2 g of diammonium titanium hexafluoride ((NH 4 ) 2 TiF 6 )) before dilution. Working standard solutions are prepared by adding the stock standard solutions of hafnium, molybdenum, and vanadium into niobium solutions. When hafnium is determined, add 2 g of (NH 4 ) 2 TiF 6 and the alloying elements in amounts corresponding to those in sample solutions into the working standard solutions. The tolerable amounts of hydrofluoric acid were 2.9 M, 2.1 M, and 3.1 M and those of nitric acid were 1.0 M, 1.6 M, and 1.6 M for hafnium, molybdenum, and vanadium, respectively. It was found that (NH 4 ) 2 TiF 6 greatly increased the sensitivity for hafnium determination. Niobium showed minus effect for hafnium and plus effect for molybdenum and vanadium. The atomic absorption of molybdenum and vanadium were not influenced by the presence of 20 % of each alloying element, while the atomic absorption of hafnium was given plus effect by 20 % of zirconium, iron, cobalt, nickel, manganese, chromium or vanadium and minus effect by 20 % tungsten. The analytical values of hafnium, molybdenum, and vanadium in niobium-based alloys by this method showed a good agreement with those by X-ray fluorescence analysis. The lower limits of determination (S/N=2) were 0.05, 0.001, and 0.002 % and the relative standard deviation were 3, 1, and 1.5 % for hafnium, molybdenum, and vanadium, respectively. (author)

  19. Separation of zirconium from hafnium by ion exchange

    Energy Technology Data Exchange (ETDEWEB)

    Felipe, Elaine C.B.; Palhares, Hugo G.; Ladeira, Ana Claudia Q., E-mail: elainecfelipe@yahoo.com.br, E-mail: hugopalhares@gmail.com, E-mail: ana.ladeira@cdtn.br [Centro de Desenvolvimento da Tecnologia Nuclear (CDTN/CNEN-MG), Belo Horizonte, MG (Brazil)

    2013-07-01

    Zirconium and hafnium are two of the most important metals for the nuclear industry. Hafnium occurs in all zirconium ores usually in the range 2 - 3%. However, for the most nuclear industry applications, it is necessary to use a zirconium of extremely pure level. The current work consists in the separation of zirconium and hafnium by the ion exchange method in order to obtain a zirconium concentrate of high purity. The zirconium and hafnium liquors were produced from the leaching of the Zr(OH){sub 4} and Hf(OH){sub 4} with nitric acid for 24 hours. From these two liquors it was prepared one solution containing 7.5 x 10{sup -2} mol L{sup -1} of Zr and 5.8 x 10{sup -3} mol L{sup -1} of Hf with acidity of 1 M. Ion exchange experiments were carried out in batch with the resins Dowex 50WX4, Dowex 50WX8 100, Dowex 50WX8 50, Amberlite IR-120 and Marathon C at constant temperature 28 deg C. Other variables such as, acidity and agitation were kept constant. The data were adjusted to Langmuir equation in order to calculate the maximum loading capacity (q{sub max}) of the resins, the distribution coefficient (K{sub d}) for Zr and Hf and the separation factor (α{sub Hf}{sup Zr} ). The results of maximum loading capacity (q{sub max}) for Zr and Hf, in mmol g{sup -}1, showed that the most suitable resins for columns experiments are: Dowex 50WX4 50 (q{sub max} Z{sub r} = 2.21, Hf = 0.18), Dowex 50WX8 50 (q{sub max} Zr = 1.89, Hf = 0.13) and Amberlite (q{sub max} Zr = 1.64, Hf = 0.12). However, separations factors, α{sub Hf}{sup Zr}, showed that the resins are not selective. (author)

  20. On the stabilization of niobium(V) solutions by zirconium(IV) and hafnium(IV)

    DEFF Research Database (Denmark)

    Sørensen, E.; Bjerre, A.B.

    1992-01-01

    Niobium cannot be separated from zirconium or hafnium when these elements occur together in solution with common anions such as chloride and sulphate. This is ascribed to the co-polymerization of niobium(V) and the hydrolysed ionic species of zirconium(IV) and hafnium(IV) to form colloidal...

  1. Analysis of hafnium in zirconium alloys

    International Nuclear Information System (INIS)

    Kondo, Isao; Sakai, Fumiaki; Ohuchi, Yoshifusa; Nakamura, Hisashi

    1977-01-01

    It is required to analyse alloying components and impurity elements in the acceptance analysis of zirconium alloys as the material for fuel cladding tubes and pressure tubes for advanced thermal reactors. Because of extreme similarity in chemical properties between zirconium and hafnium, about 100 ppm of hafnium is usually contained in zirconium alloys. Zircaloy-2 alloy and 2.5% Nb-zirconium with the addition of hafnium had been prepared as in-house standard samples for rapid analysis. Study was made on fluorescent X-ray analysis and emission spectral analysis to establish the analytical method. By using these in-house standard samples, acceptance analysis was successfully carried out for the fuel cladding tubes for advanced thermal reactors. Sulfuric acid solution was prepared from JAERI-Z 1, 2 and 3, the standard sample for zircaloy-2 prepared by the Analytical Committee on Nuclear Fuel and Reactor Materials, JAERI, and zirconium oxide (Hf 1 ppm/Zr). Standard Hf solution was added to the sulfuric acid solution step by step, to make up a series of the standard oxide samples by the precipitation process. By the use of these standard samples, the development of the analytical method and joint analysis were made by the three-member analytical technique research group including PNC. The analytical precision for the fluorescent X-ray analysis was improved by attaching a metallic yttrium filter to the window of an X-ray tube so as to suppress the effect due to zirconium matrix. The variation factor of the joint analysis was about 10% to show good agreement, and the indication value was determined. (Kobatake, H.)

  2. Knight shift in scandium and its alloys with hafnium and titanium

    International Nuclear Information System (INIS)

    Chachkhiani, Z.B.; Chechernikov, V.I.; Martynova, L.F.; Nidel'ko, V.I.; Chachkhiani, L.G.; Georgadze, G.S.

    1981-01-01

    Results of the investigation of NMR on 45 Sc nuclei and magnetic susceptibility of scandium and its solid solutions with titanium and hafnium are presented. It is shown that the existing hybridization of S and d zones in pure scandium and its alloys with titanium and hafnium affects the Knight shift reducing the value of the contact contribution. The temperature behaviour of the Knight shift from the temperature dependence and spin susceptibility of collectivized d electrons [ru

  3. Composition and microstructure of zirconium and hafnium germanates obtained by different chemical routes

    International Nuclear Information System (INIS)

    Utkin, A.V.; Prokip, V.E.; Baklanova, N.I.

    2014-01-01

    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 3 GeO 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

  4. A search for long-lived radionuclides produced by fast-neutron irradiations of copper, silver, europium, terbium, and hafnium

    International Nuclear Information System (INIS)

    Meadows, J.W.; Smith, D.L.; Ikeda, Y.; Konno, C.

    1990-01-01

    Identical sample packets, each containing samples of elemental copper, silver, europium, terbium, and hafnium, as well as titanium, iron and nickel as dosimeters, have been irradiated in three distinct accelerator neutron fields (at Argonne National Laboratory and Los Alamos National Laboratory in the U.S.A., and Japan Atomic Energy Research Institute, Tokai, Japan) as part of an interlaboratory research collaboration to search for the production of long-lived radionuclides for fusion waste disposal applications. This paper is a progress report on this project. To date, we have detected the following activities, and have obtained preliminary experimental cross section values for several of these: Ag-106m,108m,110m; Eu-150m,152g,154; Tb-158,160; and Hf-175,178m2,179m2,181. (author). 11 refs, 1 fig., 4 tabs

  5. Recovery of hafnium radioisotopes from a proton irradiated tantalum target

    International Nuclear Information System (INIS)

    Taylor, W.A.; Garcia, J.G.; Hamilton, V.T.; Heaton, R.C.; Jamriska, D.J.; Ott, M.A.; Philips, D.R.; Radzinski, S.D.

    1998-01-01

    The 178m2 Hf nucleus, with its long half-life (31 y) and high-spin isomeric state (16 + ) is desired for new and exotic nuclear physics studies. The Los Alamos Radioisotope Program irradiated a kilogram of natural tantalum at the Los Alamos Meson Physics Facility in early 1981. After fifteen years of decay, this target was ideal for the recovery of 178m2 Hf. There was more than a millicurie of 178m2 Hf produced during this irradiation and there has been a sufficient period of time for most of the other hafnium radioisotopes to decayed away. Traditionally, separation techniques for recovering hafnium isotopes from tantalum targets employ solvent extractions with reagents that are considered hazardous. These techniques are no longer condoned because they generate a mixed-waste (radioactive and hazardous components) that can not be treated for disposal. In this paper we describe a new and unique procedure for the recovery of hafnium radioisotopes from a highly radioactive, proton irradiated, tantalum target using reagents that do not contribute a hazardous waste component. (author)

  6. Investigation of colourless complexes of thorium, hafnium and zirconium

    International Nuclear Information System (INIS)

    Kiciak, S.; Stefanowicz, T.; Gontarz, H.; Swit, Z.

    1980-01-01

    The investigations conducted in the Institute of General Chemistry of Poznan Technical University in partial cooperation with Kharkhof Technical University related with thorium, hafnium and zirconium complexes are reviewed. (author)

  7. Separation process of zirconium and hafnium; Procede de separation du zirconium et du hafnium

    Energy Technology Data Exchange (ETDEWEB)

    Hure, J; Saint-James, R [Commissariat a l' Energie Atomique, Saclay (France). Centre d' Etudes Nucleaires

    1955-07-01

    About the separation different processes of zirconium-hafnium, the extraction by solvent in cross-current is the most easily the process usable on an industrial scale. It uses tributyl phosphate as solvent, diluted with white spirit to facilitate the decanting. Some exploratory tests showed that nitric environment seemed the most favorable for extraction; but a lot of other factors intervene in the separation process. We studied the influence of the acidity successively, the NO{sub 3}{sup -} ions concentration, the role of the cation coming with NO{sub 3}{sup -}, as well as the influence of the concentration of zirconium in the solution on the separation coefficient {beta} = {alpha}{sub Zr} / {alpha}{sub Hf}. (M.B.) [French] Des differents procedes de separation zirconium-hafnium, l'extraction par solvant en contre-courant est le procede le plus facilement utilisable a l'echelle industrielle. On utilise comme solvant le phosphate de tributyle, dilue avec du white spirit pour faciliter les decantations. Des essais preliminaires ont montre que le milieu nitrique semblait le plus favorable a l'extraction; mais beaucoup d'autres facteurs interviennent dans le processus de separation. Nous avons etudie successivement l'influence de l'acidite, celle de la concentration en ions NO{sub 3}{sup -}, le role du cation accompagnant NO{sub 3}{sup -}, ainsi que l'influence de la concentration en zirconium de la solution sur le coefficient de separation {beta} = {alpha}{sub Zr} / {alpha}{sub Hf}. (MB)

  8. Strong influence of polymer architecture on the microstructural evolution of hafnium-alkoxide-modified silazanes upon ceramization.

    Science.gov (United States)

    Papendorf, Benjamin; Nonnenmacher, Katharina; Ionescu, Emanuel; Kleebe, Hans-Joachim; Riedel, Ralf

    2011-04-04

    The present study focuses on the synthesis and ceramization of novel hafnium-alkoxide-modified silazanes as well as on their microstructure evolution at high temperatures. The synthesis of hafnia-modified polymer-derived SiCN ceramic nanocomposites is performed via chemical modification of a polysilazane and of a cyclotrisilazane, followed by cross-linking and pyrolysis in argon atmosphere. Spectroscopic investigation (i.e., NMR, FTIR, and Raman) shows that the hafnium alkoxide reacts with the N-H groups of the cyclotrisilazane; in the case of polysilazane, reactions of N-H as well as Si-H groups with the alkoxide are observed. Consequently, scanning and transmission electron microscopy studies reveal that the ceramic nanocomposites obtained from cyclotrisilazane and polysilazane exhibited markedly different microstructures, which is a result of the different reaction pathways of the hafnium alkoxide with cyclotrisilazane and with polysilazane. Furthermore, the two prepared ceramic nanocomposites are unexpectedly found to exhibit extremely different high-temperature behavior with respect to decomposition and crystallization; this essential difference is found to be related to the different distribution of hafnium throughout the ceramic network in the two samples. Thus, the homogeneous distribution of hafnium observed in the polysilazane-derived ceramic leads to an enhanced thermal stability with respect to decomposition, whereas the local enrichment of hafnium within the matrix of the cyclotrisilazane-based sample induces a pronounced decomposition upon annealing at high temperatures. The results indicate that the chemistry and architecture of the precursor has a crucial effect on the microstructure of the resulting ceramic material and consequently on its high-temperature behavior. Copyright © 2011 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  9. Separation of hafnium from zirconium in sulfuric acid solutions using pressurized ion exchange

    International Nuclear Information System (INIS)

    Hurst, F.J.

    1981-01-01

    High-resolution pressurized ion exchange has been used successfully to study and separate hafnium and zirconium sulfate complexes by chromatographic elution from Dowex 50W-X8 (15 to 25 μm) resin with sulfuric acid solutions. Techniques were developed to continuously monitor the column effluents for zirconium and hafnium by reaction with fluorometric and colorimetric reagents. Since neither reagent was specific for either metal ion, peak patterns were initially identified by using the stable isotopes 90 Zr and 180 Hf as fingerprints of their elution position. Distribution ratios for both zirconium and hafnium decrease as the inverse fourth power of the sulfuric acid concentration below 2N and as the inverse second power at higher acid concentration. The hafnium-to-zirconium separation factor is approximately constant (approx. 8) over the 0.5 to 3N range. Under certain conditions, an unseparated fraction was observed that was not retained by the resin. The amount of this fraction which is thought to be a polymeric hydrolysis product appears to be a function of metal and sulfuric acid concentrations. Conditions are being sought to give the highest zirconium concentration and the lowest acid concentration that can be used as a feed material for commercial scale-up in the continuous annular chromatographic (CAC) unit without formation of the polymer

  10. Separation of zirconium and hafnium from acompanying elements by paper chromatography in the systems of alcohol-acid

    International Nuclear Information System (INIS)

    Lebedeva, G.G.; Viktorova, M.E.

    1980-01-01

    Solvents have been chosen and investigated which provide expressed separation of zirconium and hafnium at the analysis of mineral raw materials by paper chromatography. The systems with HNO 3 and HCl containing methyl, ethyl, propyl and butyl alcohols have been studied as mobile phases for separation of zirconium and hafnium. It has been shown that alcohol contents and solvent acidity affect the Rsub(f) value of these elements. The C 2 H 5 OH-5MHCl and C 2 H 5 OH-5MHNO 3 systems are most optimal for pre-concentration of zirconium and hafnium

  11. Low-voltage bendable pentacene thin-film transistor with stainless steel substrate and polystyrene-coated hafnium silicate dielectric.

    Science.gov (United States)

    Yun, Dong-Jin; Lee, Seunghyup; Yong, Kijung; Rhee, Shi-Woo

    2012-04-01

    The hafnium silicate and aluminum oxide high-k dielectrics were deposited on stainless steel substrate using atomic layer deposition process and octadecyltrichlorosilane (OTS) and polystyrene (PS) were treated improve crystallinity of pentacene grown on them. Besides, the effects of the pentacene deposition condition on the morphologies, crystallinities and electrical properties of pentacene were characterized. Therefore, the surface treatment condition on dielectric and pentacene deposition conditions were optimized. The pentacene grown on polystyrene coated high-k dielectric at low deposition rate and temperature (0.2-0.3 Å/s and R.T.) showed the largest grain size (0.8-1.0 μm) and highest crystallinity among pentacenes deposited various deposition conditions, and the pentacene TFT with polystyrene coated high-k dielectric showed excellent device-performance. To decrease threshold voltage of pentacene TFT, the polystyrene-thickness on high-k dielectric was controlled using different concentration of polystyrene solution. As the polystyrene-thickness on hafnium silicate decreases, the dielectric constant of polystyrene/hafnium silicate increases, while the crystallinity of pentacene grown on polystyrene/hafnium silicate did not change. Using low-thickness polystyrene coated hafnium silicate dielectric, the high-performance and low voltage operating (pentacene thin film transistor (μ: ~2 cm(2)/(V s), on/off ratio, >1 × 10(4)) and complementary inverter (DC gains, ~20) could be fabricated.

  12. Primary hafnium metal sponge and other forms, approved standard 1973

    International Nuclear Information System (INIS)

    Anon.

    1975-01-01

    A specification is presented covering virgin hafnium metal commonly designated as sponge because of its porous, sponge-like texture; it may also be in other forms such as chunklets. The specification does not cover crystal bar

  13. Evolution of the hafnium isotopic composition in the RBMK reactor

    International Nuclear Information System (INIS)

    Jurkevicius, A.; Remeikis, V.

    2002-01-01

    The isotopic composition of hafnium in the radial neutron flux sensor of the RBMK-1500 reactor, the rates of the neutron absorption on Hf isotopes and the neutron spectrum in the sensor were numerically modeled. The sequence SAS2 (Shielding Analysis Sequence) program from the package SCALE 4.4A and the HELIOS code system were used for calculations. It has been obtained that the overall neutron absorption rates in hafnium for the sensors located in the 2.4 % and 2.6 % enrichment uranium-erbium nuclear fuel assemblies are by 16 % and 19 % lower than in the 2.0 % enrichment uranium nuclear fuel assemblies. The overall neutron absorption rate in hafnium decreases 2.70-2.75 times due to the sensor burnup to 5800 MW d. The sensitivity of the Hf sensors to the thermal neutron flux increases twice due to the nuclear fuel assembly burnup to 3000 MW d. The corrective factors ξ d (I) at the different integral current I of the sensors and ξ td (E) at the different burnup E of the nuclear fuel assemblies were calculated. The obtained dependence ξ d (I) calculated numerically was compared to the experimental one determined by comparing signals of the fresh sensor and the sensor with the integral current I and by processing repeated calibration results of Hf sensors in RBMK-1500 reactors. The relative relationship coefficients K T (T FA ) were found for all RBMK-1500 nuclear fuel types. (author)

  14. Preparation of hafnium metal by calciothermic reduction of HfO2

    International Nuclear Information System (INIS)

    Sharma, I.G.; Vijay, P.L.; Sehra, J.C.; Sundaram, C.V.

    1975-01-01

    Hafnium metal powder has been produced by the calciothermic reduction of hafnium oxide. The influence of various experimental parameters - such as amount of calcium in excess of stoichiometric requirement, temperature, and time of reduction - on the yield and purity of the metal has been studied. The metal powder obtained by reduction at 960 0 C (two hours) with a calcium excess of 70% analysed 600 ppm of oxygen and 147 ppm of nitrogen. A reduction efficiency of 96% has been achieved under these conditions. The refining of the powder by electron beam melting, fused salt electrolysis, and iodide process has been studied. The oxygen content in the metal could be brought down from 6900 to 148 ppm by electron beam melt-refining. (author)

  15. ENTIRELY AQUEOUS SOLUTION-GEL ROUTE FOR THE PREPARATION OF ZIRCONIUM CARBIDE, HAFNIUM CARBIDE AND THEIR TERNARY CARBIDE POWDERS

    Directory of Open Access Journals (Sweden)

    Zhang Changrui

    2016-07-01

    Full Text Available An entirely aqueous solution-gel route has been developed for the synthesis of zirconium carbide, hafnium carbide and their ternary carbide powders. Zirconium oxychloride (ZrOCl₂.8H₂O, malic acid (MA and ethylene glycol (EG were dissolved in water to form the aqueous zirconium carbide precursor. Afterwards, this aqueous precursor was gelled and transformed into zirconium carbide at a relatively low temperature (1200 °C for achieving an intimate mixing of the intermediate products. Hafnium and the ternary carbide powders were also synthesized via the same aqueous route. All the zirconium, hafnium and ternary carbide powders exhibited a particle size of ∼100 nm.

  16. On the phase formation of sputtered hafnium oxide and oxynitride films

    International Nuclear Information System (INIS)

    Sarakinos, K.; Music, D.; Mraz, S.; Baben, M. to; Jiang, K.; Nahif, F.; Braun, A.; Zilkens, C.; Schneider, J. M.; Konstantinidis, S.; Renaux, F.; Cossement, D.; Munnik, F.

    2010-01-01

    Hafnium oxynitride films are deposited from a Hf target employing direct current magnetron sputtering in an Ar-O 2 -N 2 atmosphere. It is shown that the presence of N 2 allows for the stabilization of the transition zone between the metallic and the compound sputtering mode enabling deposition of films at well defined conditions of target coverage by varying the O 2 partial pressure. Plasma analysis reveals that this experimental strategy facilitates control over the flux of the O - ions which are generated on the oxidized target surface and accelerated by the negative target potential toward the growing film. An arrangement that enables film growth without O - ion bombardment is also implemented. Moreover, stabilization of the transition sputtering zone and control of the O - ion flux without N 2 addition is achieved employing high power pulsed magnetron sputtering. Structural characterization of the deposited films unambiguously proves that the phase formation of hafnium oxide and hafnium oxynitride films with the crystal structure of HfO 2 is independent from the O - bombardment conditions. Experimental and theoretical data indicate that the presence of vacancies and/or the substitution of O by N atoms in the nonmetal sublattice favor the formation of the cubic and/or the tetragonal HfO 2 crystal structure at the expense of the monoclinic HfO 2 one.

  17. Solvent extraction of titanium(IV), zirconium(IV) and hafnium(IV) salicylates using liquid ion exchangers

    Energy Technology Data Exchange (ETDEWEB)

    Sundaramurthi, N M; Shinde, V M

    1989-02-01

    A solvent extraction method is proposed for the extraction of quadrivalent titanium, zirconium an hafnium from salicylate media using liquid ion exchangers such as Aliquat 336 and trioctylamine dissolved in xylene. The optimum conditions were evaluated from a critical study of the following: pH, salicylate concentration, amine concentration, diluent and period of equilibration. The method allows the separation of titanium, zirconium and hafnium from binary mixtures containing commonly associated metal ions and is applicable to the analysis of real samples such as BCS-CRM 387 nimonic 901, BCS-CRM 243/4 ferro-titanium, BCS-CRM 307 magnesium alloy and BCS-CRM 388 zircon. Titanium is determined either with hydrogen peroxide or by atomic absorption spectrometry whereas zirconium and hafnium are determined spectrophotometrically with Alizarin Red S and Zylenol Orange, respectively. The results of both separation and analysis are reported. The method is precise, accurate and fast.

  18. Solvent extraction of zirconium and hafnium using MIBK-HSCN-HCL process

    International Nuclear Information System (INIS)

    Borges, J.A.L.; Cunha, O.G.C. da

    1985-01-01

    The separation process of zirconium and hafnium, using MIBK as extractant in a set of mixer-settler is described. The chemical analysis was done by X-ray fluorescence and emission spectrography. (Author) [pt

  19. Radiation effects on the electrical properties of hafnium oxide based MOS capacitors.

    Energy Technology Data Exchange (ETDEWEB)

    Petrosky, J. C. (Air Force Institute of Technology, Wright-Patterson Air Force Base, OH); McClory, J. W. (Air Force Institute of Technology, Wright-Patterson Air Force Base, OH); Bielejec, Edward Salvador; Foster, J. C. (Air Force Institute of Technology, Wright-Patterson Air Force Base, OH)

    2010-10-01

    Hafnium oxide-based MOS capacitors were investigated to determine electrical property response to radiation environments. In situ capacitance versus voltage measurements were analyzed to identify voltage shifting as a result of changes to trapped charge with increasing dose of gamma, neutron, and ion radiation. In situ measurements required investigation and optimization of capacitor fabrication to include dicing, cleaning, metalization, packaging, and wire bonding. A top metal contact of 200 angstroms of titanium followed by 2800 angstroms of gold allowed for repeatable wire bonding and proper electrical response. Gamma and ion irradiations of atomic layer deposited hafnium oxide on silicon devices both resulted in a midgap voltage shift of no more than 0.2 V toward less positive voltages. This shift indicates recombination of radiation induced positive charge with negative trapped charge in the bulk oxide. Silicon ion irradiation caused interface effects in addition to oxide trap effects that resulted in a flatband voltage shift of approximately 0.6 V also toward less positive voltages. Additionally, no bias dependent voltage shifts with gamma irradiation and strong oxide capacitance room temperature annealing after ion irradiation was observed. These characteristics, in addition to the small voltage shifts observed, demonstrate the radiation hardness of hafnium oxide and its applicability for use in space systems.

  20. Investigation of chlorination of zirconium and hafnium and their compounds in discharge from hollow cathode

    International Nuclear Information System (INIS)

    Ioffe, R.B.; Korovin, Yu.I.

    1978-01-01

    The possibility is investigated of chlorinating various zirconium and hafnium compounds (metal, oxide, carbide) in a hot discharge from a hollow cathode with various chlorinating reagents: copper monochloride, nickel chloride, magnesium chloride, for the purpose of accelerating their entrance into the excitation zone. It has been shown thermodynamically and experimentally that chlorination of metal zirconium and hafnium and their carbides with copper monochloride in hot hollow cathode conditions provides a sharp increase in the intensity of the lines of these elements

  1. Development and characterization of ultrathin hafnium titanates as high permittivity gate insulators

    Science.gov (United States)

    Li, Min

    High permittivity or high-kappa materials are being developed for use as gate insulators for future ultrascaled metal oxide semiconductor field effect transistors (MOSFETs). Hafnium containing compounds are the leading candidates. Due to its moderate permittivity, however, it is difficult to achieve HfO2 gate structures with an EOT well below 1.0 nm. One approach to increase HfO2 permittivity is combining it with a very high-kappa material, such as TiO2. In this thesis, we systematically studied the electrical and physical characteristics of high-kappa hafnium titanates films as gate insulators. A series of HfxTi1-xO2 films with well-controlled composition were deposited using an MOCVD system. The physical properties of the films were analyzed using a variety of characterization techniques. X-ray micro diffraction indicates that the Ti-rich thin film is more immune to crystallization. TEM analysis showed that the thick stoichiometric HfTiO 4 film has an orthorhombic structure and large anisotropic grains. The C-V curves from the devices with the hafnium titanates films displayed relatively low hysteresis. In a certain composition range, the interfacial layer (IL) EOT and permittivity of HfxTi1-x O2 increases linearly with increasing Ti. The charge is negative for HfxTi1-xO2/IL and positive for Si/IL interface, and the magnitude increases as Hf increases. For ultra-thin films (less than 2 nm EOT), the leakage current increases with increasing HE Moreover, the Hf-rich sample has weaker temperature dependence of the current. In the MOSFET devices with the hafnium titanates films, normal transistor characteristics were observed, also electron mobility degradation. Next, we investigated the effects that different pre-deposition surface treatments, including HF dipping, NH3 surface nitridation, and HfO2 deposition, have on the electrical properties of hafnium titanates. Surface nitridation shows stronger effect than the thin HfO2 layer. The nitrided samples displayed a

  2. Separation of zirconium and hafnium using paper distribution chromatography

    International Nuclear Information System (INIS)

    Lebedeva, G.G.; Viktorova, M.E.

    1981-01-01

    A method is suggested of chromatographic separation of zirconium and hafnium in a CCl 4 -tributyl phosphate system (1:9) containing KCl as a salting-out agent in 5 M HNO 3 at 28-30 deg C. Zr and Hf are deterfmined in articiial mixtures under optimal chromatography conditions using visual colorimetry [ru

  3. Hafnium as a prospective absorber for VVER-1000 reactors of Ukraine

    International Nuclear Information System (INIS)

    Afanas'ev, A.A.; Konotop, Yu.F.; Odejchuk, N.L.

    2000-01-01

    Nuclear-physical parameters of hafnium having in mind its use as an absorber, are considered. Technical aspects of Hf production are exposed. Use of B 4 C/Hf absorber is twice cheaper than a standard one

  4. Evaluation of thermodynamic data on zirconium and hafnium halides and oxyhalides by means of transport experiments

    International Nuclear Information System (INIS)

    Dittmer, G.; Niemann, U.

    1987-01-01

    A consistent set of thermodynamic data for zirconium and hafnium halides, oxides and oxyhalides was achieved. It was found that formation enthalpies of gaseous compounds could be derived from solubility measurements together with theoretical estimations and a revision of literature data. Free energy functions were calculated employing statistical mechanics. Data for liquid and solid compounds were obtained via sublimation and vaporization data. Chemical equilibria of zirconium and hafnium with halogens are discussed. 51 refs.; 16 figs.; 14 tabs

  5. Electrodeposition in molten salts of metals used in nuclear industry: hafnium and uranium

    International Nuclear Information System (INIS)

    Serrano, K.

    1998-01-01

    The aim of this work is to study the electrodeposition in molten salts of metals used in nuclear industry: hafnium and uranium. The experiment is carried out in a molten alkaline halogenide medium in a temperature range between 670 and 750 degrees Celsius. The first part of this work concerns more particularly the electrochemical behaviour of the hafnium and uranium ions in the electrolytic solution. The reduction mechanisms of these ions have been studied by the use of three methods: cyclic voltametry, chrono-potentiometry and square wave voltametry. Results have shown that the process of metal deposition is difficult to explain because secondary reactions (as for instance: adsorption phenomena or cathodic deposit dissolution) occur. The uranium germination has then been studied by modelling of chrono-amperograms. The experiments have shown that the deposition is the result of the initial uranium crystal growth and depends on the electrolyte diffusion. The second part of this work deals with the implementation of hafnium and uranium deposition taking into account the preceding mechanistic studies. Depositions have all been observed by physical methods as for instance scanning electron microscopy. Particular experimental solutions (soluble anode, addition of fluoride ions to the electrolyte) have been used. The obtained deposition of hafnium is smooth and adheres very well to the substrate. The uranium depositions have been implemented with the use of a soluble anode. Uranium is deposited in a dendritic shape to the cathode. It has also been shown that the electro-kinetic parameters (temperature, uranium ions concentration, current density) have not an important influence on the dendritic morphology of the deposition. This morphology could be the consequence of particular convection movements to the surface of the cathode. (O.M.)

  6. Synthesis and characterization of Ho3+ doped hafnium oxide TLD for radiation dosimeter

    International Nuclear Information System (INIS)

    Sekar, Nandakumar; Ganesan, Bharanidharan; Sahib, Hajee Reyaz Ali; Aruna, Prakasarao; Ganesan, Singaravelu; Thamilkumar, P.; Rai, R.R.

    2017-01-01

    Cancer is a dreaded disease which is treated by Radiotherapy, Chemotherapy and Surgery. Radiotherapy plays a vital role in treatment of cancer and recently measurements of invivo radiation dosimetric in patient is of great interest due to high dose gradients in advanced technology like IMRT, IGRT etc. Hence, for the last few decades, a great degree of interest has been shown for the hafnium oxide for radiation dosimetric applications, due to its high dielectric constant, wide band gap and better interface properties such as chemical stability, conduction band offset and thermodynamic stability. In the present study, Synthesis and characterization of Ho 3+ doped Hafnium oxide were carried out and its applications towards radiation dosimeter were investigated

  7. Use of hafnium in control bars of nuclear reactors; Uso de hafnio en barras de control de reactores nucleares

    Energy Technology Data Exchange (ETDEWEB)

    Ramirez S, J.R.; Alonso V, G. [ININ, 52045 Ocoyoacac, Estado de Mexico (Mexico)]. e-mail: jrrs@nuclear.inin-mx

    2003-07-01

    Recently the use of hafnium as neutron absorber material in nuclear reactors has been reason of investigation by virtue of that this material has nuclear properties as to the neutrons absorption and structural that can prolong the useful life of the control mechanisms of the nuclear reactors. In this work some of those more significant hafnium properties are presented like nuclear material. Also there are presented calculations carried out with the HELIOS code for fuel cells of uranium oxide and of uranium and plutonium mixed oxides under controlled conditions with conventional bars of boron carbide and also with similar bars to which are substituted the absorbent material by metallic hafnium, the results are presented in this work. (Author)

  8. Plasma spraying of zirconium carbide – hafnium carbide – tungsten cermets

    Czech Academy of Sciences Publication Activity Database

    Brožek, Vlastimil; Ctibor, Pavel; Cheong, D.-I.; Yang, S.-H.

    2009-01-01

    Roč. 9, č. 1 (2009), s. 49-64 ISSN 1335-8987 Institutional research plan: CEZ:AV0Z20430508 Keywords : Plasma spraying * cermet coatings * microhardness * zirconium carbide * hafnium carbide * tungsten * water stabilized plasma Subject RIV: JH - Ceramics, Fire-Resistant Materials and Glass

  9. Extraction of zirconium and hafnium thiocyanates by CH3COCH2CH.(CH3)2-HSCN solvent from chloride medium

    International Nuclear Information System (INIS)

    Okada, A.T.

    1982-01-01

    A zirconium-hafnium separation process for application in nuclear industry is presented. The extraction of zirconium and hafnium thiocyanates in chloride medium by hexone-HSCN solvent was studied. The extraction process was developed, varying the parameters, such as, concentrations of the metals, the thiocyanate ion, the sulphate ion and free acidity in aqueous phase. (Author) [pt

  10. Separation process of zirconium and hafnium

    International Nuclear Information System (INIS)

    Hure, J.; Saint-James, R.

    1955-01-01

    About the separation different processes of zirconium-hafnium, the extraction by solvent in cross-current is the most easily the process usable on an industrial scale. It uses tributyl phosphate as solvent, diluted with white spirit to facilitate the decanting. Some exploratory tests showed that nitric environment seemed the most favorable for extraction; but a lot of other factors intervene in the separation process. We studied the influence of the acidity successively, the NO 3 - ions concentration, the role of the cation coming with NO 3 - , as well as the influence of the concentration of zirconium in the solution on the separation coefficient β = α Zr / α Hf . (M.B.) [fr

  11. Synthesis and characterization of hafnium oxide films for thermo and photoluminescence applications

    International Nuclear Information System (INIS)

    Guzman Mendoza, J.; Aguilar Frutis, M.A.; Flores, G. Alarcon; Garcia Hipolito, M.; Maciel Cerda, A.; Azorin Nieto, J.; Rivera Montalvo, T.; Falcony, C.

    2010-01-01

    Hafnium oxide (HfO 2 ) films were deposited by the ultrasonic spray pyrolysis process. The films were synthesized from hafnium chloride as raw material in deionized water as solvent and were deposited on corning glass substrates at temperatures from 300 to 600 deg. C. For substrate temperatures lower than 400 deg. C the deposited films were amorphous, while for substrate temperatures higher than 450 deg. C, the monoclinic phase of HfO 2 appeared. Scanning electron microscopy showed that the film's surface resulted rough with semi-spherical promontories. The films showed a chemical composition close to HfO 2 , with an Hf/O ratio of about 0.5. UV radiation was used in order to achieve the thermoluminescent characterization of the films; the 240 nm wavelength induced the best response. In addition, preliminary photoluminescence spectra, as a function of the deposition temperatures, are shown.

  12. A study of a production process for hafnium-free zirconium from zircon

    International Nuclear Information System (INIS)

    Ratanalert, N.

    1985-01-01

    The purpose of this experiment was to extract and purify the zirconium from zircon. The effects of time of extraction and stripping of zirconium, concentration of feed solution, concentration of hydrochloric acid in stripping process, equilibrium curve of extraction of zirconium and hafnium and equilibrium curve of stripping zirconium or scrubbing hafnium were studied from standard zirconium and hafnium. The results, subsequently were applied to the extraction procedures for zirconium from zircon. Minus 100 mesh zircon was fused with sodium hydroxide in the ratio of 1 : 6 at 700 degree C for l hour. After fusion the zirconate was leached with water and dissolved in hot concentrated hydrochloric acid. Zirconyl chloride octahydrate crystallized out when the solution was cooled. An agueons solution of zirconyl chloride was used as the feed to the hexone - thiocyanate solvent extraction process. This was prepared by dissolving zirconyl chloride octahydrate crystal in waster. This zirconium feed solution in 1 M HCl and 1 M N H 4 CNS was extracted with 2.7 m N H 4 CNS in hexone and then stripped with 3.6 M HCl the aqueous phase was got rid of thiocyanate ion by extracting with pure hexone, then the zirconium in aqueous phase was precipitated with sulfuric acid and ammonium hydroxide at pH 1.8 - 2.0 and zirconium oxide was obtained by ignition at 700 degree C. The process could be modified to improve the purity of zirconium by using cation exchange resin to get rid of thiocyanate ion after solvent extraction process

  13. 46 CFR 154.1000 - Applicability.

    Science.gov (United States)

    2010-10-01

    ... 46 Shipping 5 2010-10-01 2010-10-01 false Applicability. 154.1000 Section 154.1000 Shipping COAST GUARD, DEPARTMENT OF HOMELAND SECURITY (CONTINUED) CERTAIN BULK DANGEROUS CARGOES SAFETY STANDARDS FOR... § 154.1000 Applicability. Sections 154.1005 through 154.1020 apply to flammable cargo and ammonia...

  14. Vapor pressure, heat capacities, and phase transitions of tetrakis(tert-butoxy)hafnium

    Czech Academy of Sciences Publication Activity Database

    Fulem, Michal; Růžička, K.

    2011-01-01

    Roč. 311, Dec. (2011), s. 25-29 ISSN 0378-3812 Institutional research plan: CEZ:AV0Z10100521 Keywords : tetrakis(tert-butoxy)hafnium * MO precursor * vapor pressure * heat capacity * vaporization enthalpy * enthalpy of fusion Subject RIV: CF - Physical ; Theoretical Chemistry Impact factor: 2.139, year: 2011

  15. Pentamethylcyclopentadienyl Zirconium and Hafnium Polyhydride Complexes : Synthesis, Structure, and Reactivity

    NARCIS (Netherlands)

    Visser, Cindy; Hende, Johannes R. van den; Meetsma, Auke; Hessen, Bart; Teuben, Jan H.

    2001-01-01

    The half-sandwich zirconium and hafnium N,N-dimethylaminopropyl complexes Cp*M[(CH2)3NMe2]Cl2 (Cp* = η5-C5Me5, M = Zr, 1; Hf, 2) and Cp*M[(CH2)3NMe2]2Cl (M = Zr, 3; Hf, 4) were synthesized by mono- or dialkylation of Cp*MCl3 with the corresponding alkyllithium and Grignard reagents. Hydrogenolysis

  16. Properties of neutron-rich hafnium high-spin isomers

    CERN Multimedia

    Tungate, G; Walker, P M; Neyens, G; Billowes, J; Flanagan, K; Koester, U H; Litvinov, Y

    It is proposed to study highly-excited multi-quasiparticle isomers in neutron-rich hafnium (Z=72) isotopes. Long half-lives have already been measured for such isomers in the storage ring at GSI, ensuring their accessibility with ISOL production. The present proposal focuses on:\\\\ (i) an on-line experiment to measure isomer properties in $^{183}$Hf and $^{184}$Hf, and\\\\ (ii) an off-line molecular breakup test using REXTRAP, to provide Hf$^{+}$ beams for future laser spectroscopy and greater sensitivity for the future study of more neutron-rich isotopes.

  17. Ion-bombardment-induced reduction in vacancies and its enhanced effect on conductivity and reflectivity in hafnium nitride films

    Energy Technology Data Exchange (ETDEWEB)

    Gu, Zhiqing; Wang, Jiafu; Hu, Chaoquan; Zhang, Xiaobo; Dang, Jianchen; Gao, Jing; Zheng, Weitao [Jilin University, School of Materials Science and Engineering, Key Laboratory of Mobile Materials, MOE, and State Key Laboratory of Superhard Materials, Changchun (China); Zhang, Sam [Nanyang Technological University, School of Mechanical and Aerospace Engineering, Singapore (Singapore); Wang, Xiaoyi [Chinese Academy of Sciences, Key Laboratory of Optical System Advanced Manufacturing Technology, Changchun Institute of Optics, Fine Mechanics and Physics, Changchun (China); Chen, Hong [Jilin University, Department of Control Science and Engineering, Changchun (China)

    2016-08-15

    Although the role of ion bombardment on electrical conductivity and optical reflectivity of transition metal nitrides films was reported previously, the results were controversial and the mechanism was not yet well explored. Here, we show that proper ion bombardment, induced by applying the negative bias voltage (V{sub b}), significantly improves the electrical conductivity and optical reflectivity in rocksalt hafnium nitride films regardless of level of stoichiometry (i.e., in both near-stoichiometric HfN{sub 1.04} and over-stoichiometric HfN{sub 1.17} films). The observed improvement arises from the increase in the concentration of free electrons and the relaxation time as a result of reduction in nitrogen and hafnium vacancies in the films. Furthermore, HfN{sub 1.17} films have always much lower electrical conductivity and infrared reflectance than HfN{sub 1.04} films for a given V{sub b}, owing to more hafnium vacancies because of larger composition deviation from HfN exact stoichiometry (N:Hf = 1:1). These new insights are supported by good agreement between experimental results and theoretical calculations. (orig.)

  18. Results for heterogeneous poisoning of the critical HTR-test facility KAHTER using absorber elements containing hafnium and boron

    International Nuclear Information System (INIS)

    Drueke, V.; Filges, D.; Nabi, R.; Neef, R.D.; Paul, N.; Schaal, H.

    1979-10-01

    Experiments and checking computations for investigating the initial-core poisoning of the pebble bed high temperature reactor are described. Following the example of the THTR-300, THTR absorber elements poisoned with hafnium/boron were added to the THTR fuel- and graphite elements of the KAHTER core. Three different hafnium-boron poisoned core loadings, corresponding to 2.7, 5.3 and 8% reactivity compensation, were used in the experiments. For purposes of comparison, two cores exclusively boron poisoned were also studied. The poisoning of these cores correspond to 2.7 and 8% reactivity compensation. The experiments and checking computations should serve to test the accuracy of the theoretical models and data sets in modeling the reactivity effects of absorber poisoned elements in the THTR. In particular, the applicability of the nuclear data of hafnium and the treatment of resonance calculations should be verified. In addition, to determining critical masses and ksub(eff), special emphasis was placed in the experiments on the exact determination of all reactivity effects. In some cases, repeated loading of a configuration also provided a measure of the reproducibility of ksub(eff). The experiments were checked computationally using the GAMTEREX code package and the program system RSYST. These two computation packages contain different data bases, - although the hafnium data are identical -, and the computing models differ in certain phases of the calculations. Both code systems compute ksub(eff) values to within the present accuracy requirements, whereas the program system RSYST gives better agreement with experimental measurements. (orig.) 891 RW/orig. 892 RDG [de

  19. Thermal behaviour of hafnium diethylenetriaminepentaacetate studied using the perturbed angular correlation technique

    Energy Technology Data Exchange (ETDEWEB)

    Chain, Cecilia Y. [Universidad Nacional de La Plata (Argentina). Dept. de Fisica; Consejo Nacional de Investigaciones Cientificas y Tecnicas (CONICET), La Plata (Argentina). IFLP-CCT; Consejo Nacional de Investigaciones Cientificas y Tecnicas, Buenos Aires (Argentina); Rivas, Patricia [Consejo Nacional de Investigaciones Cientificas y Tecnicas (CONICET), La Plata (Argentina). IFLP-CCT; Consejo Nacional de Investigaciones Cientificas y Tecnicas, Buenos Aires (Argentina); Universidad Nacional de La Plata (Argentina). Facultad de Ciencias Agrarias y Forestales; Pasquevich, Alberto F. [Universidad Nacional de La Plata (Argentina). Dept. de Fisica; Consejo Nacional de Investigaciones Cientificas y Tecnicas (CONICET), La Plata (Argentina). IFLP-CCT; Comision de Investigaciones Cientificas de la Provincia de Buenos Aires (CIC-PBA) (Argentina)

    2014-07-01

    Polyaminecarboxilic ligands like diethylenetriaminepentaacetic acid form stable complexes with many heavy metal ions, excelling as cation chelants especially in the field of radiopharmacy. The aim of this work is to characterize, by using the Time Differential Perturbed Angular Correlations (TDPAC) technique, the hyperfine interactions at hafnium sites in hafnium diethylenetriaminepentaacetate and to investigate their evolution as temperature increases. TDPAC results for KHfDTPA.3H{sub 2}O obtained by chemical synthesis yield a well defined and highly asymmetric interaction of quadrupole frequency ω{sub Q} = 141 Mrad/s, which is consistent with the existence of a unique site for the metal in the crystal lattice. The thermal behaviour of the chelate is investigated by means of differential scanning calorimetry and thermogravimetrical analyses revealing that an endothermic dehydration of KHfDTPA.3H{sub 2}O takes place in one step between 80 C and 180 C. The anhydrous KHfDTPA thus arising is characterized by a fully asymmetric and well defined interaction of quadrupole frequency ω{sub Q} = 168 Mrad/s. (orig.)

  20. Thermal behaviour of hafnium diethylenetriaminepentaacetate studied using the perturbed angular correlation technique

    International Nuclear Information System (INIS)

    Chain, Cecilia Y.; Rivas, Patricia

    2014-01-01

    Polyaminecarboxilic ligands like diethylenetriaminepentaacetic acid form stable complexes with many heavy metal ions, excelling as cation chelants especially in the field of radiopharmacy. The aim of this work is to characterize, by using the Time Differential Perturbed Angular Correlations (TDPAC) technique, the hyperfine interactions at hafnium sites in hafnium diethylenetriaminepentaacetate and to investigate their evolution as temperature increases. TDPAC results for KHfDTPA.3H 2 O obtained by chemical synthesis yield a well defined and highly asymmetric interaction of quadrupole frequency ω Q = 141 Mrad/s, which is consistent with the existence of a unique site for the metal in the crystal lattice. The thermal behaviour of the chelate is investigated by means of differential scanning calorimetry and thermogravimetrical analyses revealing that an endothermic dehydration of KHfDTPA.3H 2 O takes place in one step between 80 C and 180 C. The anhydrous KHfDTPA thus arising is characterized by a fully asymmetric and well defined interaction of quadrupole frequency ω Q = 168 Mrad/s. (orig.)

  1. Studies on Optical and Electrical Properties of Hafnium Oxide Nanoparticles

    Science.gov (United States)

    Jayaraman, Venkatachalam; Sagadevan, Suresh; Sudhakar, Rajesh

    2017-07-01

    In this paper, the synthesis and physico-chemical properties of hafnium oxide nanoparticles (HfO2 NPs) are analyzed and reported. The synthesis was carried out by the precipitation route by using hafnium tetrachloride (HfCl4) as precursor material with potassium hydroxide (KOH) dissolved in Millipore water. In the precipitation technique, the chemical reaction is comparatively simple, low-cost and non-toxic compared to other synthetic methods. The synthesized HfO2 NPs were characterized by using powder x-ray diffraction (PXRD), ultraviolet-visible (UV-Vis) spectroscopy, Raman analysis, and high-resolution transmission electron microscopy (HRTEM). The monoclinic structure of the HfO2 NPs was resolved utilizing x-ray diffraction (XRD). The optical properties were studied from the UV-Vis absorption spectrum. The optical band gap of the HfO2NPs was observed to be 5.1 eV. The Raman spectrum shows the presence of HfO2 NPs. The HRTEM image showed that the HfO2 NPs were of spherical shape with an average particle size of around 28 nm. The energy-dispersive x-ray spectroscopy (EDS) spectrum obviously demonstrated the presence of HfO2 NPs. Analysis and studies on the dielectric properties of the HfO2 NPs such as the dielectric constant, the dielectric loss, and alternating current (AC) conductivity were carried out at varying frequencies and temperatures.

  2. Rare-earth hafnium oxide materials for magnetohydrodynamic (MHD) generator application

    Energy Technology Data Exchange (ETDEWEB)

    Marchant, D. D; Bates, J. L.

    1979-01-01

    Several ceramic materials based on rare-earth hafnium oxides have been identified as potential high-temperature electrodes and low-temperature current leadouts for open cycle coal-fired MHD generator channels. The electrode-current leadouts combination must operate at temperatures between 400 and 2000K with an electrical conductivity greater than 10/sup -2/ ohm/sup -1/ cm/sup -1/. The electrodes will be exposed to flowing (linear flow rates up to 100 m/s) potassium seeded coal combustion gases (plasma core temperatures between 2400 to 3200/sup 0/K) and coal slag. During operation the electrodes must conduct direct electric current at densities near 1.5 amp/cm/sup 2/. Consequently, the electrodes must be resistant to electrochemical decompositions and interactions with both the coal slag and potassium salts (e.g., K/sub 2/SO/sub 4/, K/sub 2/CO/sub 3/). The current leadout materials are placed between the hot electrodes and the water-cooled copper structural members and must have electrical conductivities greater than 10/sup -2/ ohm/sup -1/ cm/sup -1/ between 1400 and 400/sup 0/K. The current leadouts must be thermally and electrochemically compatible with the electrode, copper, and potassium salts. Ideally, the electrodes and current leadouts should exhibit minimal ionic conductivity. The fabrication, electrical conductivity, and electrochemical corrosion of rare-earth hafnium oxide materials are discussed. (WHK)

  3. 46 CFR 154.1872 - Cargo emergency jettisoning.

    Science.gov (United States)

    2010-10-01

    ... shall ensure that cargo is not jettisoned in a U.S. port. (d) When ethylene oxide is carried, the master.... Sulfur dioxide IG Yes Dry T C 154.660 (b) (3), 154.1345 (c), (d), 154.1400 (c), 154.1405, 154.1410, 154...

  4. Hafnium isotope evidence for a transition in the dynamics of continental growth 3.2 Gyr ago.

    Science.gov (United States)

    Næraa, T; Scherstén, A; Rosing, M T; Kemp, A I S; Hoffmann, J E; Kokfelt, T F; Whitehouse, M J

    2012-05-30

    Earth's lithosphere probably experienced an evolution towards the modern plate tectonic regime, owing to secular changes in mantle temperature. Radiogenic isotope variations are interpreted as evidence for the declining rates of continental crustal growth over time, with some estimates suggesting that over 70% of the present continental crustal reservoir was extracted by the end of the Archaean eon. Patterns of crustal growth and reworking in rocks younger than three billion years (Gyr) are thought to reflect the assembly and break-up of supercontinents by Wilson cycle processes and mark an important change in lithosphere dynamics. In southern West Greenland numerous studies have, however, argued for subduction settings and crust growth by arc accretion back to 3.8 Gyr ago, suggesting that modern-day tectonic regimes operated during the formation of the earliest crustal rock record. Here we report in situ uranium-lead, hafnium and oxygen isotope data from zircons of basement rocks in southern West Greenland across the critical time period during which modern-like tectonic regimes could have initiated. Our data show pronounced differences in the hafnium isotope-time patterns across this interval, requiring changes in the characteristics of the magmatic protolith. The observations suggest that 3.9-3.5-Gyr-old rocks differentiated from a >3.9-Gyr-old source reservoir with a chondritic to slightly depleted hafnium isotope composition. In contrast, rocks formed after 3.2 Gyr ago register the first additions of juvenile depleted material (that is, new mantle-derived crust) since 3.9 Gyr ago, and are characterized by striking shifts in hafnium isotope ratios similar to those shown by Phanerozoic subduction-related orogens. These data suggest a transitional period 3.5-3.2 Gyr ago from an ancient (3.9-3.5 Gyr old) crustal evolutionary regime unlike that of modern plate tectonics to a geodynamic setting after 3.2 Gyr ago that involved juvenile crust generation by plate

  5. The interaction of fast neutrons with hafnium

    International Nuclear Information System (INIS)

    Smith, A.B.

    2002-01-01

    Elemental hafnium neutron total cross sections are measured from ∼0.75 to 4.5 MeV in steps of ∼40 keV. Differential neutron elastic-scattering cross sections are measured from ∼4.5 to 10.0 MeV in ∼0.5 MeV steps and at 40 scattering angles distributed between ∼17 and 160 deg. These data are combined with those found in the literature to construct a comprehensive experimental data base which is interpreted in terms of coupled-channels models. Physical characteristics of the resulting potentials are discussed. Comparisons are made with ENDF/B-6 (MAT 7200). A detailed report of this work is given by Smith (Smith, A., 2001. Argonne National Laboratory Report ANL/NDM-153)

  6. Reinforcement against crack propagation of PWR absorbers by development of boron-carbon-hafnium composites

    International Nuclear Information System (INIS)

    Provot, B.; Herter, P.

    2000-01-01

    In order to improve the mechanical behaviour of materials used as neutron absorbers in nuclear reactors, we have developed CERCER or CERMET composites with boron and hafnium. Thus a new composite B 4 C/HfB 2 has been especially studied. We have identified three kinds of degradation under irradiation (thermal gradient, swelling due to fission products and accidental corrosion) that induce imposed deformations cracking phenomena. Mechanical behaviour and crack propagation resistance have been studied by ball-on-three-balls and double torsion tests. A special device was developed to enable crack propagation and associated stress intensity factor measurements. Effects of structure and of a second phase are underline. First results show that these materials present crack initiation and propagation resistance much higher than pure boron carbide or hafnium diboride. We observe R-Curves effects, crack bridging or branching, crack arrests, and toughness increases that we can relate respectively to the composite structures. (author)

  7. Titrimetric determination of thiocyanate in solutions of the hafnium-zirconium separation process

    International Nuclear Information System (INIS)

    Vazquez, Cristina; Botbol, Moises; Hernandez, M.H.

    1980-01-01

    The control of the thiocyanate concentration is necessary during the process of separating hafnium from zirconium by the hexone-thiocyanate method. Said control is carried out by titrimetric determination of thiocyanate in aqueous and organic solutions containing hydrochloric acid and ammonium thiocyanate in presence or absence of zirconium and/or hafnium. The method consists in a redox volumetric analysis using a cerium (IV) salt as titrating agent, and ferroine as the final point indicator. Owing to the instability of thiocyanate in an acid medium it is necessary to know previously if the decomposition of solutions with different concentration of ammonium thiocyanate and hydrochloric acid may have an influence upon the analytic results or may even invalidate them. In order to obtain reliable results, it must be taken into account that the stability of the solutions depends on the thiocyanate concentration, the acidity and the time elapsed from the moment the sample is taken until the test is performed. The decomposition process can be slowed down by cooling the solutions. This method allows to control the plant and does not require any special equipment. (M.E.L) [es

  8. Synthesis and characterization of hafnium oxide for luminescent applications

    International Nuclear Information System (INIS)

    Guzman Mendoza, J.; Aguilar Frutis, M.A.; Flores, G. Alarcon; Garcia Hipolito, M.; Azorin Nieto, J.; Rivera Montalvo, T.; Falcony, C.

    2008-01-01

    Full text: Hafnium oxide (HfO 2 ) is a material with a wide range of possible technological applications because it's chemical and physical properties such as high melting point, high chemical stability, high refraction index, high dielectric constant and hardness near to diamond in the tetragonal phase. The large energy gap and low phonon frequencies of the HfO 2 makes it appropriate as a host matrix for been doped with rare earth activators. Efficient luminescent materials find wide application in electroluminescent flat panel displays; color plasma displays panels, scintillators, cathode ray tubes, fluorescent lamps, lasers, etc. In recent years the study of luminescent materials based on HfO 2 has been intensified. Some groups have studied the optical properties of doped and undoped HfO 2 . In this contribution, Hafnium Oxide (HfO 2 ) films were prepared using the spray pyrolysis deposition technique. The material was synthesized using chlorides as raw materials in deionised water as solvent and deposited on Corning glass substrates at temperatures from 300 deg C to 600 deg C. For substrate temperatures lower than 400 deg C, the deposited films are amorphous, while for substrate temperatures higher than 450 deg C, the monoclinic phase of HfO 2 appears. Scanning electron microscopy with microprobe analysis was use to observe the microstructure and obtain the chemical composition of the films; rough surfaces with spherical particles were appreciated. UV and low energy X Ray radiations were used in order to achieve the thermoluminescent characterization of the films as a function of the deposition temperature

  9. Titanium, zirconium- and hafnium containing initiators in the polymerization of acrylic monomers to ''living'' polymers

    International Nuclear Information System (INIS)

    Farnham, W.B.; Hertler, W.R.

    1988-01-01

    This patent describes a process for preparing ''living'' polymer. The process comprises contacting one or more acrylic monomers under polymerizing conditions with a polymerization-initiating amount of a tetra-coordinate organotitanium, organozirconium or organo-hafnium polymerization initiator, and ''living'' polymers produced thereby

  10. Zirconium and hafnium tetrachloride separation by extractive distillation with molten zinc chloride lead chloride solvent

    International Nuclear Information System (INIS)

    McLaughlin, D.F.; Stoltz, R.A.

    1988-01-01

    In an extractive distillation method for separating hafniuim tetrachloride from zirconium tetrachloride of the type wherein a mixture of zirconium and hafnium tetrachlorides is introduced into an extractive distillation column, which extractive distillation column has a reboiler connected at the bottom and a reflux condenser connected at the top and wherein a molten salt solvent is circulated into the reflux condenser and through the column to provide a liquid phase, and wherein molten salt solvent containing zirconium tetrachloride is taken from the reboiler and run through a stripper to remove zirconium tetrachloride product from the molten salt solvent and the stripped molten salt solvent is returned to the reflux condenser and hafnium tetrachloride enriched vapor is taken as product from the reflux condenser, the improvement is described comprising: the molten salt having a composition of at least 30 mole percent zinc chloride and at least 10 mole percent of lead chloride

  11. 46 CFR 154.446 - Tank design.

    Science.gov (United States)

    2010-10-01

    ... 46 Shipping 5 2010-10-01 2010-10-01 false Tank design. 154.446 Section 154.446 Shipping COAST... SELF-PROPELLED VESSELS CARRYING BULK LIQUEFIED GASES Design, Construction and Equipment Independent Tank Type B § 154.446 Tank design. An independent tank type B must meet the calculations under § 154...

  12. Atomic layer deposition of calcium oxide and calcium hafnium oxide films using calcium cyclopentadienyl precursor

    International Nuclear Information System (INIS)

    Kukli, Kaupo; Ritala, Mikko; Sajavaara, Timo; Haenninen, Timo; Leskelae, Markku

    2006-01-01

    Calcium oxide and calcium hafnium oxide thin films were grown by atomic layer deposition on borosilicate glass and silicon substrates in the temperature range of 205-300 o C. The calcium oxide films were grown from novel calcium cyclopentadienyl precursor and water. Calcium oxide films possessed refractive index 1.75-1.80. Calcium oxide films grown without Al 2 O 3 capping layer occurred hygroscopic and converted to Ca(OH) 2 after exposure to air. As-deposited CaO films were (200)-oriented. CaO covered with Al 2 O 3 capping layers contained relatively low amounts of hydrogen and re-oriented into (111) direction upon annealing at 900 o C. In order to examine the application of CaO in high-permittivity dielectric layers, mixtures of Ca and Hf oxides were grown by alternate CaO and HfO 2 growth cycles at 230 and 300 o C. HfCl 4 was used as a hafnium precursor. When grown at 230 o C, the films were amorphous with equal amounts of Ca and Hf constituents (15 at.%). These films crystallized upon annealing at 750 o C, showing X-ray diffraction peaks characteristic of hafnium-rich phases such as Ca 2 Hf 7 O 16 or Ca 6 Hf 19 O 44 . At 300 o C, the relative Ca content remained below 8 at.%. The crystallized phase well matched with rhombohedral Ca 2 Hf 7 O 16 . The dielectric films grown on Si(100) substrates possessed effective permittivity values in the range of 12.8-14.2

  13. Separation of zirconium--hafnium by nitride precipitation

    International Nuclear Information System (INIS)

    Anderson, R.N.; Parlee, N.A.

    1977-01-01

    A method is described for the separation of a light reactive metal (e.g., zirconium) from a heavy reactive metal (e.g., hafnium) by forming insoluble nitrides of the metals in a molten metal solvent (e.g., copper) inert to nitrogen and having a suitable density for the light metal nitride to form a separate phase in the upper portion of the solvent and for the heavy metal nitride to form a separate phase in the lower portion of the solvent. Nitriding is performed by maintaining a nitrogen-containing atmosphere over the bath. The light and heavy metals may be an oxide mixture and carbothermically reduced to metal form in the same bath used for nitriding. The nitrides are then separately removed and decomposed to form the desired separate metals. 16 claims, 1 figure

  14. 46 CFR 154.605 - Toughness test.

    Science.gov (United States)

    2010-10-01

    ... 46 Shipping 5 2010-10-01 2010-10-01 false Toughness test. 154.605 Section 154.605 Shipping COAST....605 Toughness test. (a) Each toughness test under §§ 154.610 through 154.625 must meet Subpart 54.05 of this chapter. (b) If subsize test specimens are used for the Charpy V-notch toughness test, the...

  15. Modified method for zirconium or hafnium gravimetric determination with glycolic acid derivatives

    International Nuclear Information System (INIS)

    Barbieri, R.S.; Rocha, J.C.; Terra, V.R.; Marques Neto, A.

    1989-01-01

    The conditions for gravimetric determination of zirconium or hafnium by glicolic acid derivatives were studied by thermogravimetric analysis. The method utilized shown that after precipitation, washing and drying of precipitates at 150 0 C, the resulting solid was weighed in the form of [M{RCH(OH)COO} 4 ] (M = Zr,Hf;R = C 6 H 5 , β-C 10 H 7 ,p-BrC 6 H 4 ). (author) [pt

  16. Correlations between nuclear data and integral slab experiments: the case of hafnium; Correlations entre donnees nucleaires et experiences integrales a plaques: le cas du hafnium

    Energy Technology Data Exchange (ETDEWEB)

    Palau, J M

    1999-07-01

    The aim of this work was to evaluate how much integral slab experiments can both reduce discrepancies between experimental results and calculations, and improve the knowledge of hafnium isotopes neutronic parameters by an adapted sensitivity and uncertainty method. A statistical approach, based on the generalized least squares method and perturbation theory, has been incorporated into our calculation system in order to deduce microscopic cross-section adjustments from observed integral measurements on this particular 'mock-up' reactor.In this study it has been established that the correlations between integral parameters and hafnium capture cross-sections enable specific variations in the region of resolved resonances at the level of multigroup and punctual cross-sections recommended data (JEF-2.2 evaluation) to be highlighted. The use of determinist methods together with Monte Carlo- type simulations enabled a depth analysis of the modelling approximations to be carried out. Furthermore, the sensitivity coefficient validation technique employed leads to a reliable assessment of the quality of the new basic nuclear data. In this instance, the adjustments proposed for certain isotope {sup 177}Hf resonance parameters reduce, after error propagation, by 3 to 5 per cent the difference between experimental results and calculations related to this absorbent's efficiency. Beyond this particular application, the qualification methodology integrated in our calculation system should enable other basic sizing parameters to be treated (chemical / geometric data or other unexplored nuclear data) to make technological requirements less stringent. (author)

  17. Correlations between nuclear data and integral slab experiments: the case of hafnium; Correlations entre donnees nucleaires et experiences integrales a plaques: le cas du hafnium

    Energy Technology Data Exchange (ETDEWEB)

    Palau, J.M

    1999-07-01

    The aim of this work was to evaluate how much integral slab experiments can both reduce discrepancies between experimental results and calculations, and improve the knowledge of hafnium isotopes neutronic parameters by an adapted sensitivity and uncertainty method. A statistical approach, based on the generalized least squares method and perturbation theory, has been incorporated into our calculation system in order to deduce microscopic cross-section adjustments from observed integral measurements on this particular 'mock-up' reactor.In this study it has been established that the correlations between integral parameters and hafnium capture cross-sections enable specific variations in the region of resolved resonances at the level of multigroup and punctual cross-sections recommended data (JEF-2.2 evaluation) to be highlighted. The use of determinist methods together with Monte Carlo- type simulations enabled a depth analysis of the modelling approximations to be carried out. Furthermore, the sensitivity coefficient validation technique employed leads to a reliable assessment of the quality of the new basic nuclear data. In this instance, the adjustments proposed for certain isotope {sup 177}Hf resonance parameters reduce, after error propagation, by 3 to 5 per cent the difference between experimental results and calculations related to this absorbent's efficiency. Beyond this particular application, the qualification methodology integrated in our calculation system should enable other basic sizing parameters to be treated (chemical / geometric data or other unexplored nuclear data) to make technological requirements less stringent. (author)

  18. On-line separation of refractory hafnium and tantalum isotopes at the ISOCELE separator

    CERN Document Server

    Liang, C F; Obert, J; Paris, P; Putaux, J C

    1981-01-01

    By chemical evaporation technique, neutron deficient hafnium nuclei have been on-line separated at the ISOCELE facility, from the isobar rare-earth elements, in the metal-fluoride HfF/sub 3//sup +/ ion form. Half-lives of /sup 162-165/Hf have been measured. Similarly, tantalum has been selectively separated on the TaF/sub 4//sup +/ form. (4 refs) .

  19. Self-cleaning and surface chemical reactions during hafnium dioxide atomic layer deposition on indium arsenide.

    Science.gov (United States)

    Timm, Rainer; Head, Ashley R; Yngman, Sofie; Knutsson, Johan V; Hjort, Martin; McKibbin, Sarah R; Troian, Andrea; Persson, Olof; Urpelainen, Samuli; Knudsen, Jan; Schnadt, Joachim; Mikkelsen, Anders

    2018-04-12

    Atomic layer deposition (ALD) enables the ultrathin high-quality oxide layers that are central to all modern metal-oxide-semiconductor circuits. Crucial to achieving superior device performance are the chemical reactions during the first deposition cycle, which could ultimately result in atomic-scale perfection of the semiconductor-oxide interface. Here, we directly observe the chemical reactions at the surface during the first cycle of hafnium dioxide deposition on indium arsenide under realistic synthesis conditions using photoelectron spectroscopy. We find that the widely used ligand exchange model of the ALD process for the removal of native oxide on the semiconductor and the simultaneous formation of the first hafnium dioxide layer must be significantly revised. Our study provides substantial evidence that the efficiency of the self-cleaning process and the quality of the resulting semiconductor-oxide interface can be controlled by the molecular adsorption process of the ALD precursors, rather than the subsequent oxide formation.

  20. Ground-state structures of Hafnium clusters

    Energy Technology Data Exchange (ETDEWEB)

    Ng, Wei Chun; Yoon, Tiem Leong [School of Physics, Universiti Sains Malaysia, 11800 USM, Penang (Malaysia); Lim, Thong Leng [Faculty of Engineering and Technoloty, Multimedia University, Melaca Campus, 75450 Melaka (Malaysia)

    2015-04-24

    Hafnium (Hf) is a very large tetra-valence d-block element which is able to form relatively long covalent bond. Researchers are interested to search for substitution to silicon in the semi-conductor industry. We attempt to obtain the ground-state structures of small Hf clusters at both empirical and density-functional theory (DFT) levels. For calculations at the empirical level, charge-optimized many-body functional potential (COMB) is used. The lowest-energy structures are obtained via a novel global-minimum search algorithm known as parallel tempering Monte-Carlo Basin-Hopping and Genetic Algorithm (PTMBHGA). The virtue of using COMB potential for Hf cluster calculation lies in the fact that by including the charge optimization at the valence shells, we can encourage the formation of proper bond hybridization, and thus getting the correct bond order. The obtained structures are further optimized using DFT to ensure a close proximity to the ground-state.

  1. Molecular structure, vibrational, HOMO-LUMO, MEP and NBO analysis of hafnium selenite

    Science.gov (United States)

    Yankova, Rumyana; Genieva, Svetlana; Dimitrova, Ginka

    2017-08-01

    In hydrothermal condition hafnium selenite with estimated chemical composition Hf(SeO3)2·n(H2O) was obtained and characterized by powder X-Ray diffraction, IR spectroscopy and thermogravimetrical analysis. The composition of the obtained crystalline phase was established as dihydrate of tetraaqua complex of the hafnium selenite [Hf(SeO3)2(H2O)4]·2H2O. The results of the thermogravimetrical analysis are shown that the two hydrated water molecules are released in the temperature interval 80-110°C, while the four coordinated water molecules - at 210-300°C. By DFT method, with Becke's three parameter exchange-functional combined with gradient-corrected correlation functional of Lee, Yang and Parr and 6-31G(d), 6-311 + G(d,p) basis sets and LANL2DZ for Hf atom were calculated the molecular structure, vibrational frequencies and thermodynamic properties of the structure. The UV-Vis spectra and electronic properties are presented. The energy and oscillator strength calculated by time-dependent density functional theory corresponds well with the experimental ones. Molecular electrostatic potential (MEP) was performed. Mulliken population analysis on atomic charges was also calculated. The stability and intramolecular interactions are interpreted by NBO analysis.

  2. Near net shape processing of zirconium or hafnium metals and alloys

    International Nuclear Information System (INIS)

    Evans, S.C.

    1992-01-01

    This patent describes a process for producing a metal shape. It comprises: plasma arc melting a metal selected from zirconium, hafnium and alloys thereof comprising at least about 90 w/o of these metals to form a liquid pool; pouring the metal form the pool into a mold to form a near net shape; and reducing the metal from its near net shape to a final size while maintaining the metal temperature below the alpha-beta transition temperature throughout the size reducing step

  3. In-Pile Experiment of a New Hafnium Aluminide Composite Material to Enable Fast Neutron Testing in the Advanced Test Reactor

    Energy Technology Data Exchange (ETDEWEB)

    Donna Post Guillen; Douglas L. Porter; James R. Parry; Heng Ban

    2010-06-01

    A new hafnium aluminide composite material is being developed as a key component in a Boosted Fast Flux Loop (BFFL) system designed to provide fast neutron flux test capability in the Advanced Test Reactor. An absorber block comprised of hafnium aluminide (Al3Hf) particles (~23% by volume) dispersed in an aluminum matrix can absorb thermal neutrons and transfer heat from the experiment to pressurized water cooling channels. However, the thermophysical properties, such as thermal conductivity, of this material and the effect of irradiation are not known. This paper describes the design of an in-pile experiment to obtain such data to enable design and optimization of the BFFL neutron filter.

  4. Complexing of zirconium and hafnium with ortho-aminobenzoic acid and paraaminobenzoic acid

    International Nuclear Information System (INIS)

    Alekseeva, I.I.; Nemzer, I.I.; Yuranova, L.I.; Borisova, V.V.; Prozorovskaya, Z.N.

    1977-01-01

    Formation of complexes between zirconium and hafnium and ortho- and para-aminobenzoic acids has been studied by the kinetic method. It has been found that at pH=1.3-2.0 and concentrations of metals 10 -5 -10 -6 mole complex compounds are formed with composition Me:L=1:2 and 1:1 (Me=Zr, Hf; L=ortho- or para-aminobenzoic acids). Stepwise constants and overall effective constants of complex formation have been calculated

  5. Correlations between nuclear data and results of integral slab experiments. Case of hafnium; Correlations entre donnees nucleaires et experiences integrales a plaques: le cas du hafnium

    Energy Technology Data Exchange (ETDEWEB)

    Palau, J M

    1997-10-22

    The aim of this thesis was to evaluate how much integral slab experiments can both reduce discrepancies between experimental results and calculations, and improve the knowledge of hafnium isotopes neutronic parameters by an adapted sensitivity and uncertainty method. A statistical approach, based on the generalized least squares method and perturbation theory, has been incorporated into our calculation system in order to deduce microscopic cross-section adjustments from observed integral measurements on this particular `mock-up` reactor. In this study it has been established that the correlations between integral parameters and hafnium capture cross-sections enable specific variations in the region of resolved resonances at the level of multigroup and punctual cross-sections recommended data (JEF-2.2 evaluation) to be highlighted. The use of determinist methods (APOLLO2 code) together with Monte Carlo- type simulations (TRIPOLI4 code) enabled a depth analysis of the modelling approximations to be carried out. Furthermore, the sensitivity coefficient validation technique employed leads to a reliable assessment of the quality of the new basic nuclear data. In this instance, the adjustments proposed for certain isotope {sup 177}Hf resonance parameters reduce, after error propagation, by 3 to 5 per cent the difference between experimental results and calculations related to this absorbent`s efficiency. Beyond this particular application, the qualification methodology integrated in our calculation system should enable other basic sizing parameters to be treated (chemical / geometric data or other unexplored nuclear data) to make technological requirements less stringent. (author) 128 refs.

  6. High temperature thermodynamics of solutions of oxygen in zirconium and hafnium

    International Nuclear Information System (INIS)

    Boureau, G.; Gerdanian, P.

    1984-01-01

    The Tian-Calvet microcalorimetric method has been applied to the determination at 1323 Kelvin of ΔH(O 2 ), the partial molar enthalpy of mixing of oxygen in zirconium and in hafnium. No measurable departure from Henry's law has been found for dilute solutions (ratio oxygen over metal smaller than 0.1). For concentrated solutions repulsive interactions are found in agreement with the existence of ordered structures at lower temperatures. The domain of homogeneity of zirconium has been found larger than previously assumed. (author)

  7. 32 CFR 154.61 - Security education.

    Science.gov (United States)

    2010-07-01

    ... 32 National Defense 1 2010-07-01 2010-07-01 false Security education. 154.61 Section 154.61... PERSONNEL SECURITY PROGRAM REGULATION Continuing Security Responsibilities § 154.61 Security education. (a.... Through security briefings and education, the Department of Defense continues to provide for the...

  8. 29 CFR 1915.154 - Respiratory protection.

    Science.gov (United States)

    2010-07-01

    ... 29 Labor 7 2010-07-01 2010-07-01 false Respiratory protection. 1915.154 Section 1915.154 Labor Regulations Relating to Labor (Continued) OCCUPATIONAL SAFETY AND HEALTH ADMINISTRATION, DEPARTMENT OF LABOR... (PPE) § 1915.154 Respiratory protection. Respiratory protection for shipyard employment is covered by...

  9. 46 CFR 154.665 - Welding procedures.

    Science.gov (United States)

    2010-10-01

    ... 46 Shipping 5 2010-10-01 2010-10-01 false Welding procedures. 154.665 Section 154.665 Shipping COAST GUARD, DEPARTMENT OF HOMELAND SECURITY (CONTINUED) CERTAIN BULK DANGEROUS CARGOES SAFETY STANDARDS... Construction § 154.665 Welding procedures. Welding procedure tests for cargo tanks for a design temperature...

  10. Extraction of hafnium by 1-phenyl-3-methyl-4-benzoyl-5-pyralozone from aqueous-alcoholic solutions

    International Nuclear Information System (INIS)

    Hala, J.; Prihoda, J.

    1975-01-01

    Extraction of hafnium by 1-phenyl-3-methyl-4-benzoyl-5-pyrazolone (HL) in benzene, toluene, chloroform and tetrachloromethane from aqueous-alcoholic solutions of the formal acidity of 2M-HClO 4 was studied. Methyl, ethyl, n- and isopropyl, tert-butyl and allyl alcohol as well as ethylene glycol monomethyl ether and propylene glycol were used as organic components of the mixed aqueous-organic phase. Their presence in some cases resulted in a synergic increase in the distribution ratio of hafnium. The increase is interpreted using the results of a slope analysis and measurements of the alcohol distribution and the relative permittivity of the organic phase. It is suggested that HfL 4 molecules were solvated by alcohol molecules in the organic phase. At high alcohol concentration synergism changed into antagonism. This was caused by changes in the distribution of HL and its interaction with the alcohol in the organic phase. (author)

  11. 46 CFR 154.1020 - Emergency power.

    Science.gov (United States)

    2010-10-01

    ... 46 Shipping 5 2010-10-01 2010-10-01 false Emergency power. 154.1020 Section 154.1020 Shipping COAST GUARD, DEPARTMENT OF HOMELAND SECURITY (CONTINUED) CERTAIN BULK DANGEROUS CARGOES SAFETY STANDARDS... § 154.1020 Emergency power. The emergency generator must be designed to allow operation at the final...

  12. 46 CFR 154.703 - Methane (LNG).

    Science.gov (United States)

    2010-10-01

    ... 46 Shipping 5 2010-10-01 2010-10-01 false Methane (LNG). 154.703 Section 154.703 Shipping COAST GUARD, DEPARTMENT OF HOMELAND SECURITY (CONTINUED) CERTAIN BULK DANGEROUS CARGOES SAFETY STANDARDS FOR... and Temperature Control § 154.703 Methane (LNG). Unless a cargo tank carrying methane (LNG) can...

  13. 46 CFR 154.428 - Allowable stress.

    Science.gov (United States)

    2010-10-01

    ... 46 Shipping 5 2010-10-01 2010-10-01 false Allowable stress. 154.428 Section 154.428 Shipping COAST GUARD, DEPARTMENT OF HOMELAND SECURITY (CONTINUED) CERTAIN BULK DANGEROUS CARGOES SAFETY STANDARDS FOR... § 154.428 Allowable stress. The membrane tank and the supporting insulation must have allowable stresses...

  14. 46 CFR 154.1405 - Respiratory protection.

    Science.gov (United States)

    2010-10-01

    ... 46 Shipping 5 2010-10-01 2010-10-01 false Respiratory protection. 154.1405 Section 154.1405... Equipment § 154.1405 Respiratory protection. When Table 4 references this section, a vessel carrying the listed cargo must have: (a) Respiratory protection equipment for each person on board that protects the...

  15. 46 CFR 154.1715 - Moisture control.

    Science.gov (United States)

    2010-10-01

    ... 46 Shipping 5 2010-10-01 2010-10-01 false Moisture control. 154.1715 Section 154.1715 Shipping COAST GUARD, DEPARTMENT OF HOMELAND SECURITY (CONTINUED) CERTAIN BULK DANGEROUS CARGOES SAFETY STANDARDS... § 154.1715 Moisture control. When a vessel is carrying sulfur dioxide, the master shall ensure that: (a...

  16. Trap state passivation improved hot-carrier instability by zirconium-doping in hafnium oxide in a nanoscale n-metal-oxide semiconductor-field effect transistors with high-k/metal gate

    International Nuclear Information System (INIS)

    Liu, Hsi-Wen; Tsai, Jyun-Yu; Liu, Kuan-Ju; Lu, Ying-Hsin; Chang, Ting-Chang; Chen, Ching-En; Tseng, Tseung-Yuen; Lin, Chien-Yu; Cheng, Osbert; Huang, Cheng-Tung; Ye, Yi-Han

    2016-01-01

    This work investigates the effect on hot carrier degradation (HCD) of doping zirconium into the hafnium oxide high-k layer in the nanoscale high-k/metal gate n-channel metal-oxide-semiconductor field-effect-transistors. Previous n-metal-oxide semiconductor-field effect transistor studies demonstrated that zirconium-doped hafnium oxide reduces charge trapping and improves positive bias temperature instability. In this work, a clear reduction in HCD is observed with zirconium-doped hafnium oxide because channel hot electron (CHE) trapping in pre-existing high-k bulk defects is the main degradation mechanism. However, this reduced HCD became ineffective at ultra-low temperature, since CHE traps in the deeper bulk defects at ultra-low temperature, while zirconium-doping only passivates shallow bulk defects.

  17. 29 CFR 1917.154 - Compressed air.

    Science.gov (United States)

    2010-07-01

    ... 29 Labor 7 2010-07-01 2010-07-01 false Compressed air. 1917.154 Section 1917.154 Labor Regulations...) MARINE TERMINALS Related Terminal Operations and Equipment § 1917.154 Compressed air. Employees shall be... this part during cleaning with compressed air. Compressed air used for cleaning shall not exceed a...

  18. 46 CFR 154.660 - Pipe welding.

    Science.gov (United States)

    2010-10-01

    ... 46 Shipping 5 2010-10-01 2010-10-01 false Pipe welding. 154.660 Section 154.660 Shipping COAST GUARD, DEPARTMENT OF HOMELAND SECURITY (CONTINUED) CERTAIN BULK DANGEROUS CARGOES SAFETY STANDARDS FOR... § 154.660 Pipe welding. (a) Pipe welding must meet Part 57 of this chapter. (b) Longitudinal butt welds...

  19. 46 CFR 154.420 - Tank design.

    Science.gov (United States)

    2010-10-01

    ... 46 Shipping 5 2010-10-01 2010-10-01 false Tank design. 154.420 Section 154.420 Shipping COAST... SELF-PROPELLED VESSELS CARRYING BULK LIQUEFIED GASES Design, Construction and Equipment Integral Tanks § 154.420 Tank design. (a) The structure of an integral tank must meet the deep tank scantling standards...

  20. 46 CFR 154.449 - Model test.

    Science.gov (United States)

    2010-10-01

    ... 46 Shipping 5 2010-10-01 2010-10-01 false Model test. 154.449 Section 154.449 Shipping COAST GUARD, DEPARTMENT OF HOMELAND SECURITY (CONTINUED) CERTAIN BULK DANGEROUS CARGOES SAFETY STANDARDS FOR SELF... § 154.449 Model test. The following analyzed data of a model test of structural elements for independent...

  1. 11 CFR 100.154 - Candidate debates.

    Science.gov (United States)

    2010-01-01

    ... 11 Federal Elections 1 2010-01-01 2010-01-01 false Candidate debates. 100.154 Section 100.154 Federal Elections FEDERAL ELECTION COMMISSION GENERAL SCOPE AND DEFINITIONS (2 U.S.C. 431) Exceptions to Expenditures § 100.154 Candidate debates. Funds used to defray costs incurred in staging candidate debates in...

  2. Determination of hafnium with the inductively coupled plasma (ICP)

    International Nuclear Information System (INIS)

    Wuensch, G.; Pose, K.

    1985-01-01

    The relative intensities of 198 hafnium lines in the Ar-ICP are listed. Spectral interference tables are given for the 9 analytically best lines, covering the range of +-60 pm around the Hf-lines. They include measured (not calculated) data of the interferent equivalent concentrations (IEC) and the critical concentration ratios (CCR) for 115 lines of all 34 possibly interfering elements. In many cases, these IEC- or CCR-data differ by 1 or 2 orders of magnitude from those calculated from intensities observed in the NBS-copper arc. Since no intense Hf-line is free from spectral interferences, examples are given for the calculation of the most suitable line for a known matrix. (orig.) [de

  3. 18 CFR 154.307 - Joint facilities.

    Science.gov (United States)

    2010-04-01

    ... 18 Conservation of Power and Water Resources 1 2010-04-01 2010-04-01 false Joint facilities. 154... Changes § 154.307 Joint facilities. The Statements required by § 154.312 must show all costs (investment... in the subject rate change and are associated with joint facilities. The methods used in making such...

  4. 46 CFR 154.439 - Tank design.

    Science.gov (United States)

    2010-10-01

    ... 46 Shipping 5 2010-10-01 2010-10-01 false Tank design. 154.439 Section 154.439 Shipping COAST... SELF-PROPELLED VESSELS CARRYING BULK LIQUEFIED GASES Design, Construction and Equipment Independent Tank Type A § 154.439 Tank design. An independent tank type A must meet the deep tank standard of the...

  5. 46 CFR 154.421 - Allowable stress.

    Science.gov (United States)

    2010-10-01

    ... 46 Shipping 5 2010-10-01 2010-10-01 false Allowable stress. 154.421 Section 154.421 Shipping COAST... § 154.421 Allowable stress. The allowable stress for the integral tank structure must meet the American Bureau of Shipping's allowable stress for the vessel's hull published in “Rules for Building and Classing...

  6. 46 CFR 154.430 - Material test.

    Science.gov (United States)

    2010-10-01

    ... 46 Shipping 5 2010-10-01 2010-10-01 false Material test. 154.430 Section 154.430 Shipping COAST... § 154.430 Material test. (a) The membrane and the membrane supporting insulation must be made of... test for the membrane and the membrane supporting insulation must be submitted to the Commandant (CG...

  7. 46 CFR 154.804 - Vacuum protection.

    Science.gov (United States)

    2010-10-01

    ... 46 Shipping 5 2010-10-01 2010-10-01 false Vacuum protection. 154.804 Section 154.804 Shipping... Systems § 154.804 Vacuum protection. (a) Except as allowed under paragraph (b) of this section, each cargo tank must have a vacuum protection system meeting paragraph (a)(1) of this section and either paragraph...

  8. 46 CFR 154.447 - Allowable stress.

    Science.gov (United States)

    2010-10-01

    ... 46 Shipping 5 2010-10-01 2010-10-01 false Allowable stress. 154.447 Section 154.447 Shipping COAST... Tank Type B § 154.447 Allowable stress. (a) An independent tank type B designed from bodies of revolution must have allowable stresses 3 determined by the following formulae: 3 See Appendix B for stress...

  9. 46 CFR 154.440 - Allowable stress.

    Science.gov (United States)

    2010-10-01

    ... 46 Shipping 5 2010-10-01 2010-10-01 false Allowable stress. 154.440 Section 154.440 Shipping COAST... Tank Type A § 154.440 Allowable stress. (a) The allowable stresses for an independent tank type A must... Commandant (CG-522). (b) A greater allowable stress than required in paragraph (a)(1) of this section may be...

  10. Dicty_cDB: SFF154 [Dicty_cDB

    Lifescience Database Archive (English)

    Full Text Available SF (Link to library) SFF154 (Link to dictyBase) - - - Contig-U15074-1 SFF154P (Link... to Original site) SFF154F 132 SFF154Z 514 SFF154P 646 - - Show SFF154 Library SF (Link to library) Clone ID SFF154 (Link to dict...yBase) Atlas ID - NBRP ID - dictyBase ID - Link to Contig Contig-U15074-1 Original site URL http://dict...22, genomic survey sequence. 48 3e-09 3 AC116921 |AC116921.2 Dictyostelium discoi...deum chromosome 2 map 4624505-4657775 strain AX4, complete sequence. 44 4e-09 7 BQ096682 |BQ096682.1 IfHdk00151 Ict

  11. Atom-vacancy ordering and magnetic susceptibility of nonstoichiometric hafnium carbide

    International Nuclear Information System (INIS)

    Gusev, A.I.; Zyryanova, A.N.

    1999-01-01

    Experimental results on magnetic susceptibility of nonstoichiometric hafnium carbide HfC y (0.6 0.71 , HfC 0.78 and HfC 0.83 in the range of 870-930 K the anomalies are revealed which are associated with superstructure short-range ordering in a non-metallics sublattice. It is shown that a short-range order in HfC 0.71 and HfC 0.78 carbides corresponds to Hf 3 C 2 ordered phase, and in HfC 0.83 carbide - to Hf 6 C 5 ordered phase. HfC 0.78 carbide is found to possesses zero magnetic susceptibility in temperature range 910-980 K [ru

  12. Hafnium carbide nanocrystal chains for field emitters

    International Nuclear Information System (INIS)

    Tian, Song; Li, Hejun; Zhang, Yulei; Ren, Jincui; Qiang, Xinfa; Zhang, Shouyang

    2014-01-01

    A hafnium carbide (HfC) nanostructure, i.e., HfC nanocrystal chain, was synthesized by a chemical vapor deposition (CVD) method. X-ray diffractometer, field-emission scanning electron microscope, transmission electron microscope, and energy-dispersive X-ray spectrometer were employed to characterize the product. The synthesized one-dimensional (1D) nanostructures with many faceted octahedral nanocrystals possess diameters of tens of nanometers to 500 nm and lengths of a few microns. The chain-like structures possess a single crystalline structure and preferential growth direction along the [1 0 0] crystal orientation. The growth of the chains occurred through the vapor–liquid–solid process along with a negative-feedback mechanism. The field emission (FE) properties of the HfC nanocrystal chains as the cold cathode emitters were examined. The HfC nanocrystal chains display good FE properties with a low turn-on field of about 3.9 V μm −1 and a high field enhancement factor of 2157, implying potential applications in vacuum microelectronics.

  13. Simplified method for gravimetric determination of zirconium or hafnium with α-hydroxy carboxylic acids

    International Nuclear Information System (INIS)

    Barbieri, R.S.; Rocha, J.C.; Terra, V.R.; Marques Netto, A.

    1989-01-01

    The conditions for gravimetric determination of zirconium or hafnium by glicoloc acids derivatives were studied by thermogravimetric analysis. The method utilized shownd that after precipitation, washing and drying of precipitates at 150 o C, the resulting solid was weighed in the form of [M (RCH(OH)COO) 4 ] (M = Zr, Hf; R + C 6 H 5 , β-C 10 H 7 , p-BrC 6 H 4 ). (author)

  14. Complexonometric determination of hafnium (4) in the presence of europium(3) or tantalum(5)

    International Nuclear Information System (INIS)

    Oziashvili, E.D.; Ehsakiya, K.E.; Sirakanyan, N.M.

    1986-01-01

    Complexonometric determination of hafnium in the presence of Ta or Eu in samples which can be decomposed by acids, i.e. in double borides has been investigated. Initial solutions are prepared by fusing with K 2 S 2 O 8 excess, the fusion was leached by hot water, H 2 SO L 4 was added and Hf was titrated by complexone 3 in the presence of xylenol orange

  15. Investigation of interaction of zirconium and hafnium tetrafluorides with strontium fluoride

    International Nuclear Information System (INIS)

    Ratnikova, I.D.; Korenev, Yu.M.; Novoselova, A.V.

    1980-01-01

    Diagrams of the condensated state of systems SrF 2 -EF 4 have been plotted, where E represents Zr, Hf. In these systems, three intermediate compounds of Sr 3 EF 10 , Sr 2 EF 8 and Sr EF 6 compositions are formed. All those compounds melt incongruently at temperatures of 982, 865 and 750 deg C, respectively - zirconium salt; at temperatures of 1000, 900 and 820 deg C - hafnium salts. Fluoro-metallates of composition 2:1, and 1:1, exist in two polymorphic forms. Tetrafluorides were found to dissolve in strontium fluoride: they form solid solutions having fluorite structure

  16. Correlations between nuclear data and integral slab experiments: the case of hafnium

    International Nuclear Information System (INIS)

    Palau, J.M.

    1999-01-01

    The aim of this work was to evaluate how much integral slab experiments can both reduce discrepancies between experimental results and calculations, and improve the knowledge of hafnium isotopes neutronic parameters by an adapted sensitivity and uncertainty method. A statistical approach, based on the generalized least squares method and perturbation theory, has been incorporated into our calculation system in order to deduce microscopic cross-section adjustments from observed integral measurements on this particular 'mock-up' reactor.In this study it has been established that the correlations between integral parameters and hafnium capture cross-sections enable specific variations in the region of resolved resonances at the level of multigroup and punctual cross-sections recommended data (JEF-2.2 evaluation) to be highlighted. The use of determinist methods together with Monte Carlo- type simulations enabled a depth analysis of the modelling approximations to be carried out. Furthermore, the sensitivity coefficient validation technique employed leads to a reliable assessment of the quality of the new basic nuclear data. In this instance, the adjustments proposed for certain isotope 177 Hf resonance parameters reduce, after error propagation, by 3 to 5 per cent the difference between experimental results and calculations related to this absorbent's efficiency. Beyond this particular application, the qualification methodology integrated in our calculation system should enable other basic sizing parameters to be treated (chemical / geometric data or other unexplored nuclear data) to make technological requirements less stringent. (author)

  17. 33 CFR 154.1020 - Definitions.

    Science.gov (United States)

    2010-07-01

    ... Coordinator (OSC) means the definition in the National Oil and Hazardous Substances Pollution Contingency Plan... Contingency Plan (ACP) (for planning) or by members of the Federal On-Scene Coordinator's spill response... 33 Navigation and Navigable Waters 2 2010-07-01 2010-07-01 false Definitions. 154.1020 Section 154...

  18. Laser coating of hafnium on Ti6Al4 for biomedical applications

    CSIR Research Space (South Africa)

    Phume, L

    2012-12-01

    Full Text Available Al4V FOR BIOMEDICAL APPLICATIONS Lerato Phume 1, 2, S.L. Pityana 1, 2, C. Meacock 1, A.P.I Popoola 2 1. National Laser Centre, Council for Scientific and Industrial Research, P.O. Box 395, Pretoria, 0001, South Africa 2. Department of Chemical... and Metallurgical Engineering, Tshwane University of Technology, Private Bag X 680, Pretoria, 0001, South Africa (b) (c) (e) To investigate laser surface coating of Ti6Al4V with preplaced Hafnium powder, to determine the influence of the energy density...

  19. Preparation, structure and properties of hafnium compounds in the system Hf-C-N-O

    International Nuclear Information System (INIS)

    Brundiers, G.D.

    1975-08-01

    Highly dense, homogenous and single phase hafnium carbonitride samples (with low oxygen content) were prepared in the whole concentration range of the ternary cubic carbonitrides. Stoichiometric hafnium oxicarbides were also prepared within the range of solubility. The procedure involved the hot pressing of powders of HfC, HfN, Hf, Hf-Oxide and carbon at temperatures of 3,000 0 C and pressures up to 550 kpf/cm 2 using a novel technique. Small single crystals of slightly substoichiometric HfN were also repared. The densification of the powders was studied as a function of the non-metal concentration. Carbonitrides with N/Hf ratio of 0.37 were prepared in a high temperature autoclave operating at medium pressures by the reaction of HfC with nitrogen. All the samples were characterized by density measurements, chemical, X-ray and metallographic analysis and in some cases with the aid of quantitative metallography and microprobe analysis. Typical properties investigated were lattice parameter, thermal expansion, microhardness and electrical resistivity as function of the non-metal content. For specific concentrations extreme values in the properties are attained. With the aid of the valence electron concentration (VEC) parameter, the properties can be correlated with the density of states of electrons at the Fermi level. (orig./HK) [de

  20. 46 CFR 154.516 - Piping: Hull protection.

    Science.gov (United States)

    2010-10-01

    ... 46 Shipping 5 2010-10-01 2010-10-01 false Piping: Hull protection. 154.516 Section 154.516 Shipping COAST GUARD, DEPARTMENT OF HOMELAND SECURITY (CONTINUED) CERTAIN BULK DANGEROUS CARGOES SAFETY... and Process Piping Systems § 154.516 Piping: Hull protection. A vessel's hull must be protected from...

  1. 46 CFR 154.1145 - Dry chemical supply.

    Science.gov (United States)

    2010-10-01

    ... 46 Shipping 5 2010-10-01 2010-10-01 false Dry chemical supply. 154.1145 Section 154.1145 Shipping COAST GUARD, DEPARTMENT OF HOMELAND SECURITY (CONTINUED) CERTAIN BULK DANGEROUS CARGOES SAFETY STANDARDS... Firefighting System: Dry Chemical § 154.1145 Dry chemical supply. (a) A vessel with a cargo carrying capacity...

  2. 46 CFR 154.235 - Cargo tank location.

    Science.gov (United States)

    2010-10-01

    ... 46 Shipping 5 2010-10-01 2010-10-01 false Cargo tank location. 154.235 Section 154.235 Shipping COAST GUARD, DEPARTMENT OF HOMELAND SECURITY (CONTINUED) CERTAIN BULK DANGEROUS CARGOES SAFETY STANDARDS... Survival Capability and Cargo Tank Location § 154.235 Cargo tank location. (a) For type IG hulls, cargo...

  3. Systematic investigation of electromagnetic properties of all stable hafnium isotopes

    International Nuclear Information System (INIS)

    Napiorkowski, T.J.; Choinski, J.; Czosnyka, T.; Iwanicki, J.; Kownacki, J.; Zemlo, L.; Srebrny, J.; Starosta, K.; Boer, J. de.; Gollwitzer, A.; Loewe, M.; Wuerkner, M.; Guenther, C.; Weber, T.; Hagemann, G.; Sletten, G.

    1996-01-01

    In a systematic investigation of the electromagnetic structure of hafnium stable isotopes enriched targets of 176, 177, 178, 179, 180 Hf were Coulomb exciting using: 67 MeV 19 F beam from NBITAL FN Tandem, 125 MeV 32 S beam from MP Tandem in Accelerator Laboratory LMU and TU Munich, 225 MeV 58 Ni beam from NBITAL FN Tandem plus 2 Liniac Boosters complex. Scattered particle-gamma as well as p-γ-γ coincidence were registered. A further simultaneous analysis of Coulomb excitation cross section as a function of scattering angle of 19 F, 32 S, 58 Ni projectiles should be sufficient to deduce reduced probabilities of E2 transitions in ground state band

  4. 46 CFR 154.1755 - Nitrogen.

    Science.gov (United States)

    2010-10-01

    ... 46 Shipping 5 2010-10-01 2010-10-01 false Nitrogen. 154.1755 Section 154.1755 Shipping COAST GUARD... Nitrogen. Except for deck tanks and their piping systems, cargo containment systems and piping systems carrying nitrogen must be specially approved by the Commandant (CG-522). [CGD 74-289, 44 FR 26009, May 3...

  5. 46 CFR 154.1816 - Cargo location plan.

    Science.gov (United States)

    2010-10-01

    ... 46 Shipping 5 2010-10-01 2010-10-01 false Cargo location plan. 154.1816 Section 154.1816 Shipping... FOR SELF-PROPELLED VESSELS CARRYING BULK LIQUEFIED GASES Operations § 154.1816 Cargo location plan. The master shall ensure that: (a) A cargo location plan is prepared that gives: (1) The location and...

  6. 46 CFR 154.1702 - Materials of construction.

    Science.gov (United States)

    2010-10-01

    ... 46 Shipping 5 2010-10-01 2010-10-01 false Materials of construction. 154.1702 Section 154.1702... § 154.1702 Materials of construction. When Table 4 references one of the following paragraphs in this section, the materials in the referenced paragraph must not be in components that contact the cargo liquid...

  7. 46 CFR 154.801 - Pressure relief systems.

    Science.gov (United States)

    2010-10-01

    ... 46 Shipping 5 2010-10-01 2010-10-01 false Pressure relief systems. 154.801 Section 154.801 Shipping COAST GUARD, DEPARTMENT OF HOMELAND SECURITY (CONTINUED) CERTAIN BULK DANGEROUS CARGOES SAFETY... Vent Systems § 154.801 Pressure relief systems. (a) Each cargo tank that has a volume of 20m3 (706 ft.3...

  8. 18 CFR 154.502 - Reports.

    Science.gov (United States)

    2010-04-01

    ... 18 Conservation of Power and Water Resources 1 2010-04-01 2010-04-01 false Reports. 154.502... OF ENERGY REGULATIONS UNDER NATURAL GAS ACT RATE SCHEDULES AND TARIFFS Refunds and Reports § 154.502 Reports. (a) When the natural gas company is required, either by a Commission order or as a part of a...

  9. Highly substituted zirconium and hafnium cyclopentadienyl bifunctional β-diketiminate complexes – Synthesis, structure, and catalytic activity towards ethylene polymerization

    Czech Academy of Sciences Publication Activity Database

    Havlík, A.; Lamač, Martin; Pinkas, Jiří; Varga, Vojtěch; Růžička, A.; Olejník, R.; Horáček, Michal

    2015-01-01

    Roč. 786, JUN 2015 (2015), s. 71-80 ISSN 0022-328X R&D Projects: GA ČR GAP106/10/0924 Institutional support: RVO:61388955 Keywords : Zirconium * Hafnium * Cyclopentadienyl Subject RIV: CF - Physical ; Theoretical Chemistry Impact factor: 2.336, year: 2015

  10. 46 CFR 154.1135 - Pumps.

    Science.gov (United States)

    2010-10-01

    ... 46 Shipping 5 2010-10-01 2010-10-01 false Pumps. 154.1135 Section 154.1135 Shipping COAST GUARD... Pumps. (a) Water to the water spray system must be supplied by: (1) A pump that is only for the use of the system; (2) A fire pump; or (3) A pump specially approved by the Commandant (CG-522). (b...

  11. Wake-up effects in Si-doped hafnium oxide ferroelectric thin films

    International Nuclear Information System (INIS)

    Zhou, Dayu; Xu, Jin; Li, Qing; Guan, Yan; Cao, Fei; Dong, Xianlin; Müller, Johannes; Schenk, Tony; Schröder, Uwe

    2013-01-01

    Hafnium oxide based ferroelectric thin films have shown potential as a promising alternative material for non-volatile memory applications. This work reports the switching stability of a Si-doped HfO 2 film under bipolar pulsed-field operation. High field cycling causes a “wake-up” in virgin “pinched” polarization hysteresis loops, demonstrated by an enhancement in remanent polarization and a shift of negative coercive voltage. The rate of wake-up is accelerated by either reducing the frequency or increasing the amplitude of the cycling field. We suggest de-pinning of domains due to reduction of the defect concentration at bottom electrode interface as origin of the wake-up

  12. Correlations between nuclear data and results of integral slab experiments. Case of hafnium

    International Nuclear Information System (INIS)

    Palau, J.M.

    1997-01-01

    The aim of this thesis was to evaluate how much integral slab experiments can both reduce discrepancies between experimental results and calculations, and improve the knowledge of hafnium isotopes neutronic parameters by an adapted sensitivity and uncertainty method. A statistical approach, based on the generalized least squares method and perturbation theory, has been incorporated into our calculation system in order to deduce microscopic cross-section adjustments from observed integral measurements on this particular 'mock-up' reactor. In this study it has been established that the correlations between integral parameters and hafnium capture cross-sections enable specific variations in the region of resolved resonances at the level of multigroup and punctual cross-sections recommended data (JEF-2.2 evaluation) to be highlighted. The use of determinist methods (APOLLO2 code) together with Monte Carlo- type simulations (TRIPOLI4 code) enabled a depth analysis of the modelling approximations to be carried out. Furthermore, the sensitivity coefficient validation technique employed leads to a reliable assessment of the quality of the new basic nuclear data. In this instance, the adjustments proposed for certain isotope 177 Hf resonance parameters reduce, after error propagation, by 3 to 5 per cent the difference between experimental results and calculations related to this absorbent's efficiency. Beyond this particular application, the qualification methodology integrated in our calculation system should enable other basic sizing parameters to be treated (chemical / geometric data or other unexplored nuclear data) to make technological requirements less stringent. (author)

  13. Extraction of hafnium with chelating agents from aqueous-alcoholic solutions

    International Nuclear Information System (INIS)

    Hala, J.; Prihoda, J.

    1975-01-01

    The extraction was studied of hafnium into solutions of N-benzoyl-N-phenylhydroxylamine, 2-thenoyltrifluoroacetone and di-n-butylphosphoric acid in benzene, toluene, chloroform and tetrachloromethane from aqueous alcoholic solutions with a formal acidity of 2M-HClO 4 . Methyl-, ethyl-, n- and isopropyl- and tert-butyl alcohol were used as organic components in the mixed aqueous-organic phase. In the extraction into N-benzoyl-N-phenylhydroxylamine the presence of the alcohols resulted in synergic effects analogous to the previously described extraction by substituted benzoylpyrazolone. With the other two extractants, the effect of the alcohols was antagonistic, due to the interaction of alcohol or water with the reagent in the organic phase, and to the decrease in the reagent distribution constant. (author)

  14. Studies of high-K isomers in hafnium nuclei

    International Nuclear Information System (INIS)

    Sletten, G.; Gjoerup, N.L.

    1991-01-01

    K-isomeric states built on high-Ω Nilsson orbitals from deformation-aligned high-j levels near the Fermi surface are found to cluster in the neutron rich Hf, W and Os nuclei. It has been shown that some of the high seniority states of this type have decay properties that indicate strong mixing of configurations and that in Osmium nuclei γ-softness cause strong deviations from the well established K-selection rule. Also in the Hafnium nuclei is the expected forbiddenness in isomeric decays an order of magnitude smaller than expected from the K-selection rule. A new 9 quasiparticle isomer has been discovered in 175 Hf at I=57/2. This isomer has the anomalous decay as the dominant mode. Other lower seniority states are also identified. At spin 35/2 and 45/2 the deformation aligned states become yrast, but the structure of the yrast line to even higher spins is not yet understood. (author)

  15. Luminescent determination of zirconium and hafnium with myricetin

    International Nuclear Information System (INIS)

    Talipov, Sh.T.; Zel'tser, L.E.; Morozova, L.A.; Tashkhodzhaev, A.T.

    1978-01-01

    Reaction of formation of 3, 5, 7, 3', 4', 5' - hexaoxiflavone - myricetin complexes with zirconium and hafnium ions has been the basis for development of luminescent method of determining these elements. Optimum conditions for complexing have been determined. For Hf they are : 8-9 HCl concentration, maximum fluorescence wave length (lambda fl.)of 520 nm, wave length of exciting light (lambda el) of 436 nm, for Zr lambda fl = 536nm, lambda el = 436 nm. Stable fluorescence establishes after 25 min. for Zr and after 15 min for Hf in the presence of 40% ethanol. Usage of various camouflage agents has permitted to attain high selectivity of the method. Possibility for determination of Zr with myricetin in the presence of a 10-time excess of Hf, Cr, Cu, 50-time excess of Mo and Ti is shown. Sensitivity of Zr determination is 2.0x10 μg -2 /ml, for Hf it is 9.0x10 μg -3 and mineral waters

  16. Amorphous Hafnium-Indium-Zinc Oxide Semiconductor Thin Film Transistors

    Directory of Open Access Journals (Sweden)

    Sheng-Po Chang

    2012-01-01

    Full Text Available We reported on the performance and electrical properties of co-sputtering-processed amorphous hafnium-indium-zinc oxide (α-HfIZO thin film transistors (TFTs. Co-sputtering-processed α-HfIZO thin films have shown an amorphous phase in nature. We could modulate the In, Hf, and Zn components by changing the co-sputtering power. Additionally, the chemical composition of α-HfIZO had a significant effect on reliability, hysteresis, field-effect mobility (μFE, carrier concentration, and subthreshold swing (S of the device. Our results indicated that we could successfully and easily fabricate α-HfIZO TFTs with excellent performance by the co-sputtering process. Co-sputtering-processed α-HfIZO TFTs were fabricated with an on/off current ratio of ~106, higher mobility, and a subthreshold slope as steep as 0.55 V/dec.

  17. 154 GHz collective Thomson scattering in LHD

    Science.gov (United States)

    Tanaka, K.; Nishiura, M.; Kubo, S.; Shimozuma, T.; Saito, T.; Moseev, D.; Abramovic, I.

    2018-01-01

    Collective Thomson scattering (CTS) was developed by using a 154 GHz gyrotron, and the first data has been obtained. Already, 77 GHz CTS has worked successfully. However, in order to access higher density region, 154 GHz option enhances the usability that reduces the refraction effect, which deteriorates in the local measurements. The system in the down converted frequency was almost identical to the system for 77 GHz. Probing beam, a notch filter, a mixer, and a local oscillator in the receiver system for 77 GHz option were replaced to those for the 154 GHz option. 154 GHz gyrotron was originally prepared for the second harmonic electron cyclotron heating (ECRH) at 2.75 T. However, scattering signal was masked by the second harmonic electron cyclotron emission (ECE) at 2.75 T. Therefore, 154 GHz CTS was operated at 1.375 T with fourth harmonic ECE, and an acceptable signal to noise ratio was obtained. There is a signature of fast ion components with neutral beam (NB) injection. In addition, the CTS spectrum became broader in hydrogen discharge than in deuterium discharge, as the theoretical CTS spectrum expects. This observation indicates a possibility to identify ion species ratio by the 154 GHz CTS diagnostic.

  18. 42 CFR 441.154 - Active treatment.

    Science.gov (United States)

    2010-10-01

    ... 42 Public Health 4 2010-10-01 2010-10-01 false Active treatment. 441.154 Section 441.154 Public Health CENTERS FOR MEDICARE & MEDICAID SERVICES, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED... treatment. Inpatient psychiatric services must involve “active treatment”, which means implementation of a...

  19. 46 CFR 154.910 - Inert gas piping: Location.

    Science.gov (United States)

    2010-10-01

    ... 46 Shipping 5 2010-10-01 2010-10-01 false Inert gas piping: Location. 154.910 Section 154.910 Shipping COAST GUARD, DEPARTMENT OF HOMELAND SECURITY (CONTINUED) CERTAIN BULK DANGEROUS CARGOES SAFETY... Atmospheric Control in Cargo Containment Systems § 154.910 Inert gas piping: Location. Inert gas piping must...

  20. 46 CFR 154.908 - Inert gas generator: Location.

    Science.gov (United States)

    2010-10-01

    ... 46 Shipping 5 2010-10-01 2010-10-01 false Inert gas generator: Location. 154.908 Section 154.908 Shipping COAST GUARD, DEPARTMENT OF HOMELAND SECURITY (CONTINUED) CERTAIN BULK DANGEROUS CARGOES SAFETY... Atmospheric Control in Cargo Containment Systems § 154.908 Inert gas generator: Location. (a) Except as...

  1. 46 CFR 154.1350 - Flammable gas detection system.

    Science.gov (United States)

    2010-10-01

    ... 46 Shipping 5 2010-10-01 2010-10-01 false Flammable gas detection system. 154.1350 Section 154... Equipment Instrumentation § 154.1350 Flammable gas detection system. (a) The vessel must have a fixed flammable gas detection system that has sampling points in: (1) Each cargo pump room; (2) Each cargo...

  2. 46 CFR 154.562 - Cargo hose: Hydrostatic test.

    Science.gov (United States)

    2010-10-01

    ... 46 Shipping 5 2010-10-01 2010-10-01 false Cargo hose: Hydrostatic test. 154.562 Section 154.562 Shipping COAST GUARD, DEPARTMENT OF HOMELAND SECURITY (CONTINUED) CERTAIN BULK DANGEROUS CARGOES SAFETY... Hose § 154.562 Cargo hose: Hydrostatic test. Each cargo hose must pass a hydrostatic pressure test at...

  3. 33 CFR 154.1216 - Facility classification.

    Science.gov (United States)

    2010-07-01

    ... 33 Navigation and Navigable Waters 2 2010-07-01 2010-07-01 false Facility classification. 154.1216... Vegetable Oils Facilities § 154.1216 Facility classification. (a) The Coast Guard classifies facilities that... classification of a facility that handles, stores, or transports animal fats or vegetable oils. The COTP may...

  4. 45 CFR 400.154 - Employability services.

    Science.gov (United States)

    2010-10-01

    ...) Employability assessment services, including aptitude and skills testing. (c) On-the job training, when such... driver education and training when provided as part of an individual employability plan. (f) Skills... 45 Public Welfare 2 2010-10-01 2010-10-01 false Employability services. 400.154 Section 400.154...

  5. 34 CFR 668.154 - Institutional accountability.

    Science.gov (United States)

    2010-07-01

    ... 34 Education 3 2010-07-01 2010-07-01 false Institutional accountability. 668.154 Section 668.154 Education Regulations of the Offices of the Department of Education (Continued) OFFICE OF POSTSECONDARY... accountability. An institution shall be liable for the Title IV, HEA program funds disbursed to a student whose...

  6. 33 CFR 154.1075 - Appeal process.

    Science.gov (United States)

    2010-07-01

    ... 33 Navigation and Navigable Waters 2 2010-07-01 2010-07-01 false Appeal process. 154.1075 Section 154.1075 Navigation and Navigable Waters COAST GUARD, DEPARTMENT OF HOMELAND SECURITY (CONTINUED....1075 Appeal process. (a) Any owner or operator of a facility who desires to appeal the classification...

  7. 46 CFR 154.1760 - Liquid ammonia.

    Science.gov (United States)

    2010-10-01

    ... 46 Shipping 5 2010-10-01 2010-10-01 false Liquid ammonia. 154.1760 Section 154.1760 Shipping COAST GUARD, DEPARTMENT OF HOMELAND SECURITY (CONTINUED) CERTAIN BULK DANGEROUS CARGOES SAFETY STANDARDS FOR....1760 Liquid ammonia. The master shall ensure that no person sprays liquid ammonia into a cargo tank...

  8. 40 CFR 93.154 - Conformity analysis.

    Science.gov (United States)

    2010-07-01

    ... 40 Protection of Environment 20 2010-07-01 2010-07-01 false Conformity analysis. 93.154 Section 93...) DETERMINING CONFORMITY OF FEDERAL ACTIONS TO STATE OR FEDERAL IMPLEMENTATION PLANS Determining Conformity of General Federal Actions to State or Federal Implementation Plans § 93.154 Conformity analysis. Any Federal...

  9. 46 CFR 154.170 - Outer hull steel plating.

    Science.gov (United States)

    2010-10-01

    ... 46 Shipping 5 2010-10-01 2010-10-01 false Outer hull steel plating. 154.170 Section 154.170... STANDARDS FOR SELF-PROPELLED VESSELS CARRYING BULK LIQUEFIED GASES Design, Construction and Equipment Hull Structure § 154.170 Outer hull steel plating. (a) Except as required in paragraph (b) of this section, the...

  10. 46 CFR 154.172 - Contiguous steel hull structure.

    Science.gov (United States)

    2010-10-01

    ... 46 Shipping 5 2010-10-01 2010-10-01 false Contiguous steel hull structure. 154.172 Section 154.172... STANDARDS FOR SELF-PROPELLED VESSELS CARRYING BULK LIQUEFIED GASES Design, Construction and Equipment Hull Structure § 154.172 Contiguous steel hull structure. (a) Except as allowed in paragraphs (b) and (c) of this...

  11. 46 CFR 154.1435 - Medical first aid guide.

    Science.gov (United States)

    2010-10-01

    ... 46 Shipping 5 2010-10-01 2010-10-01 false Medical first aid guide. 154.1435 Section 154.1435 Shipping COAST GUARD, DEPARTMENT OF HOMELAND SECURITY (CONTINUED) CERTAIN BULK DANGEROUS CARGOES SAFETY... Equipment § 154.1435 Medical first aid guide. Each vessel must have a copy of the IMO Medical First Aid...

  12. 46 CFR 154.1110 - Areas protected by system.

    Science.gov (United States)

    2010-10-01

    ... 46 Shipping 5 2010-10-01 2010-10-01 false Areas protected by system. 154.1110 Section 154.1110... Firefighting § 154.1110 Areas protected by system. Each water spray system must protect: (a) All cargo tank... valves essential to cargo flow; (f) Each boundary facing the cargo area of each superstructure that...

  13. Differential perturbed angular correlation: use of physico-chemical study of some hafnium complexes derivates of hydroxy acids and EDTA

    International Nuclear Information System (INIS)

    Silveira, J.G. da.

    1981-01-01

    Measures of quadrupolar interaction to nucleus level of the metal, in some hafnium complexes are presented, including the analysis by combustion, microanalysis, infrared spectroscopy and thermogravimetry. The hyperfine interaction parameters, the temperature effects and the thermal neutrons capture effects over the irradiated Hf Y (Y = EDTA) are also studied. (author)

  14. Rhodium and Hafnium Influence on the Microstructure, Phase Composition, and Oxidation Resistance of Aluminide Coatings

    OpenAIRE

    Maryana Zagula-Yavorska; Małgorzata Wierzbińska; Jan Sieniawski

    2017-01-01

    A 0.5 μm thick layer of rhodium was deposited on the CMSX 4 superalloy by the electroplating method. The rhodium-coated superalloy was hafnized and aluminized or only aluminized using the Chemical vapour deposition method. A comparison was made of the microstructure, phase composition, and oxidation resistance of three aluminide coatings: nonmodified (a), rhodium-modified (b), and rhodium- and hafnium-modified (c). All three coatings consisted of two layers: the additive layer and the interdi...

  15. Study of bulk Hafnium oxide (HfO2) under compression

    Science.gov (United States)

    Pathak, Santanu; Mandal, Guruprasad; Das, Parnika

    2018-04-01

    Hafnium oxide (HfO2) is a technologically important material. This material has K-value of 25 and band gap 5.8 eV. A k value of 25-30 is preferred for a gate dielectric [1]. As it shows good insulating and capacitive properties, HfO2 is being considered as a replacement to SiO2 in microelectronic devices as gate dielectrics. On the other hand because of toughening mechanism due to phase transformation induced by stress field observed in these oxides, HFO2 has been a material of investigations in various configurations for a very long time. However the controversies about phase transition of HfO2 under pressure still exists. High quality synchrotron radiation has been used to study the structural phase transition of HfO2 under pressure.

  16. Hafnium at subduction zones: isotopic budget of input and output fluxes; L'hafnium dans les zones de subduction: bilan isotopique des flux entrant et sortant

    Energy Technology Data Exchange (ETDEWEB)

    Marini, J.Ch

    2004-05-15

    Subduction zones are the primary regions of mass exchanges between continental crust and mantle of Earth through sediment subduction toward the earth's mantle and by supply of mantellic magmas to volcanic arcs. We analyze these mass exchanges using Hafnium and Neodymium isotopes. At the Izu-Mariana subduction zone, subducting sediments have Hf and Nd isotopes equivalent to Pacific seawater. Altered oceanic crust has Hf and Nd isotopic compositions equivalent to the isotopic budget of unaltered Pacific oceanic crust. At Luzon and Java subduction zones, arc lavas present Hf isotopic ratios highly radiogenic in comparison to their Nd isotopic ratios. Such compositions of the Luzon and Java arc lavas are controlled by a contamination of their sources by the subducted oceanic sediments. (author)

  17. 46 CFR 154.460 - Design criteria.

    Science.gov (United States)

    2010-10-01

    ... GUARD, DEPARTMENT OF HOMELAND SECURITY (CONTINUED) CERTAIN BULK DANGEROUS CARGOES SAFETY STANDARDS FOR... Barrier § 154.460 Design criteria. At static angles of heel up through 30°, a secondary barrier must (a) If a complete secondary barrier is required in § 154.459, hold all of the liquid cargo in the cargo...

  18. 46 CFR 154.560 - Cargo hose: Prototype test.

    Science.gov (United States)

    2010-10-01

    ... 46 Shipping 5 2010-10-01 2010-10-01 false Cargo hose: Prototype test. 154.560 Section 154.560... Hose § 154.560 Cargo hose: Prototype test. (a) Each cargo hose must be of a type that passes a prototype test at a pressure of at least five times its maximum working pressure at or below the minimum...

  19. 46 CFR 154.1150 - Distribution of dry chemical.

    Science.gov (United States)

    2010-10-01

    ... 46 Shipping 5 2010-10-01 2010-10-01 false Distribution of dry chemical. 154.1150 Section 154.1150... Firefighting System: Dry Chemical § 154.1150 Distribution of dry chemical. (a) All locations on the above deck... chemical hand hose lines; or (2) At least one dry chemical hand hose line and one dry chemical monitor. (b...

  20. 46 CFR 154.431 - Model test.

    Science.gov (United States)

    2010-10-01

    ... 46 Shipping 5 2010-10-01 2010-10-01 false Model test. 154.431 Section 154.431 Shipping COAST GUARD... Model test. (a) The primary and secondary barrier of a membrane tank, including the corners and joints...(c). (b) Analyzed data of a model test for the primary and secondary barrier of the membrane tank...

  1. 46 CFR 154.1725 - Ethylene oxide.

    Science.gov (United States)

    2010-10-01

    ... 46 Shipping 5 2010-10-01 2010-10-01 false Ethylene oxide. 154.1725 Section 154.1725 Shipping COAST....1725 Ethylene oxide. (a) A vessel carrying ethylene oxide must: (1) Have cargo piping, vent piping, and... space of an ethylene oxide cargo tank for a period of 30 days under the condition of paragraph (e) of...

  2. 27 CFR 28.154 - Export marks.

    Science.gov (United States)

    2010-04-01

    ... 27 Alcohol, Tobacco Products and Firearms 1 2010-04-01 2010-04-01 false Export marks. 28.154..., for Exportation or Transfer to a Foreign-Trade Zone § 28.154 Export marks. In addition to the marks... provisions of part 19 of this chapter, the proprietor shall mark the word “Export” on the Government side of...

  3. Hafnium at subduction zones: isotopic budget of input and output fluxes

    International Nuclear Information System (INIS)

    Marini, J.Ch.

    2004-05-01

    Subduction zones are the primary regions of mass exchanges between continental crust and mantle of Earth through sediment subduction toward the earth's mantle and by supply of mantellic magmas to volcanic arcs. We analyze these mass exchanges using Hafnium and Neodymium isotopes. At the Izu-Mariana subduction zone, subducting sediments have Hf and Nd isotopes equivalent to Pacific seawater. Altered oceanic crust has Hf and Nd isotopic compositions equivalent to the isotopic budget of unaltered Pacific oceanic crust. At Luzon and Java subduction zones, arc lavas present Hf isotopic ratios highly radiogenic in comparison to their Nd isotopic ratios. Such compositions of the Luzon and Java arc lavas are controlled by a contamination of their sources by the subducted oceanic sediments. (author)

  4. Thermal expansion studies on Hafnium titanate (HfTiO4)

    International Nuclear Information System (INIS)

    Panneerselvam, G.; Subramanian, G.G.S.; Antony, M.P.

    2006-01-01

    The lattice thermal expansion characteristics of hafnium titanate (HfTiO 4 ) have been studied by measuring the lattice parameter as a function of temperature by high temperature X-ray diffraction technique (HT-XRD) in the temperature range 298-1973K. Percentage linear thermal expansion and mean linear thermal expansion coefficients were computed from the lattice parameter data. The thermal expansion of HfTiO 4 is highly anisotropic. The expansivity along 'a' axis is large; as compared to the expansivity along 'b' axis which is negative below 1073 K. The percentage linear thermal expansion in the temperature range 298-1973 K along a, b and c axis are 2.74, 0.901 and 1.49 respectively. Thermal expansion values obtained in the present study are in reasonable agreement with the existing thermal expansion data. (author)

  5. 46 CFR 154.534 - Cargo pumps and cargo compressors.

    Science.gov (United States)

    2010-10-01

    ... 46 Shipping 5 2010-10-01 2010-10-01 false Cargo pumps and cargo compressors. 154.534 Section 154.534 Shipping COAST GUARD, DEPARTMENT OF HOMELAND SECURITY (CONTINUED) CERTAIN BULK DANGEROUS CARGOES... Equipment Cargo and Process Piping Systems § 154.534 Cargo pumps and cargo compressors. Cargo pumps and...

  6. 46 CFR 154.188 - Membrane tank: Inner hull steel.

    Science.gov (United States)

    2010-10-01

    ... 46 Shipping 5 2010-10-01 2010-10-01 false Membrane tank: Inner hull steel. 154.188 Section 154.188... STANDARDS FOR SELF-PROPELLED VESSELS CARRYING BULK LIQUEFIED GASES Design, Construction and Equipment Hull Structure § 154.188 Membrane tank: Inner hull steel. For a vessel with membrane tanks, the inner hull...

  7. 18 CFR 154.302 - Previously submitted material.

    Science.gov (United States)

    2010-04-01

    ... 18 Conservation of Power and Water Resources 1 2010-04-01 2010-04-01 false Previously submitted material. 154.302 Section 154.302 Conservation of Power and Water Resources FEDERAL ENERGY REGULATORY... concurrently with the rate change filing. There must be furnished to the Director, Office of Energy Market...

  8. Surface State Capture Cross-Section at the Interface between Silicon and Hafnium Oxide

    Directory of Open Access Journals (Sweden)

    Fu-Chien Chiu

    2013-01-01

    Full Text Available The interfacial properties between silicon and hafnium oxide (HfO2 are explored by the gated-diode method and the subthreshold measurement. The density of interface-trapped charges, the current induced by surface defect centers, the surface recombination velocity, and the surface state capture cross-section are obtained in this work. Among the interfacial properties, the surface state capture cross-section is approximately constant even if the postdeposition annealing condition is changed. This effective capture cross-section of surface states is about 2.4 × 10−15 cm2, which may be an inherent nature in the HfO2/Si interface.

  9. A thermally robust and thickness independent ferroelectric phase in laminated hafnium zirconium oxide

    Directory of Open Access Journals (Sweden)

    S. Riedel

    2016-09-01

    Full Text Available Ferroelectric properties in hafnium oxide based thin films have recovered the scaling potential for ferroelectric memories due to their ultra-thin-film- and CMOS-compatibility. However, the variety of physical phenomena connected to ferroelectricity allows a wider range of applications for these materials than ferroelectric memory. Especially mixed HfxZr1-xO2 thin films exhibit a broad compositional range of ferroelectric phase stability and provide the possibility to tailor material properties for multiple applications. Here it is shown that the limited thermal stability and thick-film capability of HfxZr1-xO2 can be overcome by a laminated approach using alumina interlayers.

  10. 46 CFR 154.1015 - Lighting in gas-dangerous space.

    Science.gov (United States)

    2010-10-01

    ... 46 Shipping 5 2010-10-01 2010-10-01 false Lighting in gas-dangerous space. 154.1015 Section 154... Equipment Electrical § 154.1015 Lighting in gas-dangerous space. (a) Each gas-dangerous space that has... protective device for any lighting circuit that is in a gas-dangerous space must open each conductor of the...

  11. Influence of plastic deformation on nitriding of a molybdenum-hafnium alloy

    International Nuclear Information System (INIS)

    Lakhtin, Yu.M.; Kogan, Ya.D.; Shashkov, D.P.; Likhacheva, T.E.

    1982-01-01

    The influence of a preliminary plastic strain on the structure and properties of molybdenum alloy with 0.2 wt.% Hf upon nitriding in the ammonia medium at 900-1200 deg C during 1-6 h is investigated. The study of microhardness distribution across the nitrided layer thickness has shown that with increase of the degree of preliminary plastic strain up to 50 % the nitrided layer hardness decreases and with further reduction growth up to 90 % - increases. Nitriding sharply (hundred times) increases wear resistance of molybdenum alloy with hafnium addition. At the reduction degree 25 % the wear resistance is less than at other values of percentage reduction in area owing to the minimum thickness of the nitride zone. The alloy strained before nitriding by 25 % has shown the best results during heat resistance testing

  12. 18 CFR 154.5 - Rejection of filings.

    Science.gov (United States)

    2010-04-01

    ... 18 Conservation of Power and Water Resources 1 2010-04-01 2010-04-01 false Rejection of filings. 154.5 Section 154.5 Conservation of Power and Water Resources FEDERAL ENERGY REGULATORY COMMISSION... Director of the Office of Energy Market Regulation pursuant to the authority delegated to the Director in...

  13. 29 CFR 1926.154 - Temporary heating devices.

    Science.gov (United States)

    2010-07-01

    ... 29 Labor 8 2010-07-01 2010-07-01 false Temporary heating devices. 1926.154 Section 1926.154 Labor... Temporary heating devices. (a) Ventilation. (1) Fresh air shall be supplied in sufficient quantities to... heating devices shall be installed to provide clearance to combustible material not less than the amount...

  14. Dielectric response and ac conductivity analysis of hafnium oxide nanopowder

    International Nuclear Information System (INIS)

    Karahaliou, P K; Xanthopoulos, N; Krontiras, C A; Georga, S N

    2012-01-01

    The dielectric response of hafnium oxide nanopowder was studied in the frequency range of 10 -2 -10 6 MHz and in the temperature range of 20-180 °C. Broadband dielectric spectroscopy was applied and the experimental results were analyzed and discussed using the electric modulus (M*) and alternating current (ac) conductivity formalisms. The analyses of the dc conductivity and electric modulus data revealed the presence of mechanisms which are thermally activated, both with almost the same activation energy of 1.01 eV. A fitting procedure involving the superposition of the thermally activated dc conductivity, the universal dielectric responce and the near constant loss terms has been used to describe the frequency evolution of the real part of the specific electrical conductivity. The conductivity master curve was obtained, suggesting that the time-temperature superposition principle applies for the studied system, thus implying that the conductivity mechanisms are temperature independent.

  15. Interface and oxide traps in high-κ hafnium oxide films

    International Nuclear Information System (INIS)

    Wong, H.; Zhan, N.; Ng, K.L.; Poon, M.C.; Kok, C.W.

    2004-01-01

    The origins of the interface trap generation and the effects of thermal annealing on the interface and bulk trap distributions are studied in detail. We found that oxidation of the HfO 2 /Si interface, removal of deep trap centers, and crystallization of the as-deposited film will take place during the post-deposition annealing (PDA). These processes will result in the removal of interface traps and deep oxide traps and introduce a large amount of shallow oxide traps at the grain boundaries of the polycrystalline film. Thus, trade-off has to be made in considering the interface trap density and oxide trap density when conducting PDA. In addition, the high interface trap and oxide trap densities of the HfO 2 films suggest that we may have to use the SiO 2 /HfO 2 stack or hafnium silicate structure for better device performance

  16. Effects of oxygen partial pressure and annealing temperature on the residual stress of hafnium oxide thin-films on silicon using synchrotron-based grazing incidence X-ray diffraction

    Energy Technology Data Exchange (ETDEWEB)

    Biswas, Debaleen [Saha Institute of Nuclear Physics, 1/AF Bidhannagar, Kolkata 700 064 (India); Sinha, Anil Kumar [ISU, Raja Ramanna Centre for Advanced Technology, Indore 452 013 (India); Homi Bhabha National Institute, BARC, Mumbai 400 094 (India); Chakraborty, Supratic, E-mail: supratic.chakraborty@saha.ac.in [Saha Institute of Nuclear Physics, 1/AF Bidhannagar, Kolkata 700 064 (India)

    2016-10-30

    Highlights: • Residual stress estimation thin hafnium oxide film with thickness of <10 nm. • A mathematical expression is proposed for stress estimation of thin-film using GIXRD. • Residual stress varies with argon content in Ar/O{sub 2} plasma and annealing temperature. • Variation of stress is explained by IL swelling and enhanced structural relaxation. - Abstract: Synchrotron radiation-based grazing incidence X-ray diffraction (GI-XRD) technique is employed here to estimate the residual stress of < 10 nm thin hafnium oxide film deposited on Si (100) substrate at different argon/oxygen ratios using reactive rf sputtering. A decrease in residual stress, tensile in nature, is observed at higher annealing temperature for the samples deposited with increasing argon ratio in the Ar/O{sub 2} plasma. The residual stress of the films deposited at higher p{sub Ar} (Ar:O{sub 2} = 4:1) is also found to be decreased with increasing annealing temperature. But the stress is more or less constant with annealing temperature for the films deposited at lower Ar/O{sub 2} (1:4) ratio. All the above phenomena can be explained on the basis of swelling of the interfacial layer and enhanced structural relaxation in the presence of excess Hf in hafnium oxide film during deposition.

  17. 46 CFR 154.1750 - Butadiene or vinyl chloride: Refrigeration system.

    Science.gov (United States)

    2010-10-01

    ... and Operating Requirements § 154.1750 Butadiene or vinyl chloride: Refrigeration system. A... 46 Shipping 5 2010-10-01 2010-10-01 false Butadiene or vinyl chloride: Refrigeration system. 154.1750 Section 154.1750 Shipping COAST GUARD, DEPARTMENT OF HOMELAND SECURITY (CONTINUED) CERTAIN BULK...

  18. 18 CFR 154.111 - Index of customers.

    Science.gov (United States)

    2010-04-01

    ... 18 Conservation of Power and Water Resources 1 2010-04-01 2010-04-01 false Index of customers. 154... Tariff § 154.111 Index of customers. (a) If a pipeline is in compliance with the reporting requirements of § 284.13(c) of this chapter, then an index of customers need not be provided in the tariff. (b) If...

  19. 46 CFR 154.1814 - Cargo information cards.

    Science.gov (United States)

    2010-10-01

    ... 46 Shipping 5 2010-10-01 2010-10-01 false Cargo information cards. 154.1814 Section 154.1814... cards. (a) No person may operate a vessel unless a cargo information card for each cargo being... accessible to the person in charge of the watch. (b) When a vessel is moored at a terminal, the master shall...

  20. Pyroelectricity of silicon-doped hafnium oxide thin films

    Science.gov (United States)

    Jachalke, Sven; Schenk, Tony; Park, Min Hyuk; Schroeder, Uwe; Mikolajick, Thomas; Stöcker, Hartmut; Mehner, Erik; Meyer, Dirk C.

    2018-04-01

    Ferroelectricity in hafnium oxide thin films is known to be induced by various doping elements and in solid-solution with zirconia. While a wealth of studies is focused on their basic ferroelectric properties and memory applications, thorough studies of the related pyroelectric properties and their application potential are only rarely found. This work investigates the impact of Si doping on the phase composition and ferro- as well as pyroelectric properties of thin film capacitors. Dynamic hysteresis measurements and the field-free Sharp-Garn method were used to correlate the reported orthorhombic phase fractions with the remanent polarization and pyroelectric coefficient. Maximum values of 8.21 µC cm-2 and -46.2 µC K-1 m-2 for remanent polarization and pyroelectric coefficient were found for a Si content of 2.0 at%, respectively. Moreover, temperature-dependent measurements reveal nearly constant values for the pyroelectric coefficient and remanent polarization over the temperature range of 0 ° C to 170 ° C , which make the material a promising candidate for IR sensor and energy conversion applications beyond the commonly discussed use in memory applications.

  1. Implantation of titanium, chromium, yttrium, molybdenum, silver, hafnium, tantalum, tungsten and platinum ions generated by a metal vapor vacuum ion source into 440C stainless steel

    International Nuclear Information System (INIS)

    Sasaki, Jun; Hayashi, Kazunori; Sugiyama, Kenji; Ichiko, Osami; Hashiguchi, Yoshihiro

    1992-01-01

    Titanium, yttrium, molybdenum, silver, chromium, hafnium, tantalum, tungsten and platinum ions generated by a metal vapor vacuum arc (MEVVA) ion source were implanted into 440C stainless steel in the dose region 10 17 ions cm -2 with extraction voltages of up to 70 kV. Glow discharge spectroscopy (GDS), friction coefficient, and Vickers microhardness of the specimens were studied. Grooves made by friction tests were investigated by electron probe microanalysis (EPMA). GDS showed incorporation of carbon in the yttrium, hafnium, tantalum, tungsten and platinum implanted specimens, as well as titanium implanted samples. A large amount of oxygen was observed in the yttrium implanted specimen. The friction coefficient was measured by reciprocating sliding of an unimplanted 440C ball without lubricant at a load of 0.245 N. The friction decreased and achieved a stable state after implantation of titanium, hafnium and tantalum. The friction coefficient of the platinum implanted specimen showed a gradual decrease after several cycles of sliding at high friction coefficient. The yttrium implanted sample exhibited a decreased but slightly unstable friction coefficient. Results from EPMA showed that the implanted elements, which gave decreased friction, remained even after sliding of 200 cycles. Implantation of chromium, molybdenum, silver and tungsten did not provide a decrease in friction and the implants were gone from the wear grooves after the sliding tests. (orig.)

  2. Critical evaluation of the determination of zirconium and hafnium by instrumental and radiochemical neutron activation analysis

    International Nuclear Information System (INIS)

    Burger, Mario; Kraehenbuehl, Urs

    1991-01-01

    Neutron activation analysis (instrument or radiochemical) is suitable for the determination of zirconium and hafnium in samples of geochemical origin only when sufficient attention is paid to inter-fering nuclides. The size of the necessary correction for INAA depends on the composition of the sample; this problem is discussed. The radio-chemical technique which is recommended involves separation of the samples, precipitations and anion-exchange separation. Results are given for various standard reference materials and for meteorites. (author). 12 refs.; 1 fig.; 9 tabs

  3. A fast response hafnium selective polymeric membrane electrode based on N,N'-bis(α-methyl-salicylidene)-dipropylenetriamine as a neutral carrier

    International Nuclear Information System (INIS)

    Rezaei, B.; Meghdadi, S.; Zarandi, R. Fazel

    2008-01-01

    In this study a new hafnium selective sensor was fabricated from polyvinylchloride (PVC) matrix membrane containing neutral carrier N,N'-bis(α-methyl-salicylidene)-dipropylenetriamine (Mesaldpt) as a new ionophore, sodium tetraphenyl borate (NaTPB) as anionic discriminator and dioctyl phthalate (DOP) as plasticizing solvent mediator in tetrahydrofuran solvent. The electrode exhibits Nernstian response for Hf 4+ (Hafnium(IV)) over a wide concentration range (2.0 x 10 -7 to 1.0 x 10 -1 M) with the determination coefficient of 0.9966 and slope of 15.1 ± 0.1 mV decades -1 . The limit of detection is 1.9 x 10 -7 M. The electrode has a fast response time of 18 s and a working pH range of 4-8. The proposed membrane shows excellent discriminating ability towards Hf 4+ ion with regard to several alkali, alkaline earth transition and heavy metal ions. It can be used over a period of 1.5 months with good reproducibility. It is successfully applied for direct determination of Hf 4+ in solutions by standard addition method for real sample analysis

  4. Study of hafnium (IV) oxide nanoparticles synthesized by polymerized complex and polymer precursor derived sol-gel methods

    KAUST Repository

    Ramos-Gonzá lez, R.; Garcí a-Cerda, L. A.; Alshareef, Husam N.; Gnade, Bruce E.; Quevedo-Ló pez, Manuel Angel Quevedo

    2010-01-01

    This work reports the preparation and characterization of hafnium (IV) oxide (HfO2) nanoparticles grown by derived sol-gel routes that involves the formation of an organic polymeric network. A comparison between polymerized complex (PC) and polymer precursor (PP) methods is presented. For the PC method, citric acid (CA) and ethylene glycol (EG) are used as the chelating and polymerizable reagents, respectively. In the case of PP method, poly(acrylic acid) (PAA) is used as the chelating reagent. In both cases, different precursor gels were prepared and the hafnium (IV) chloride (HfCl4) molar ratio was varied from 0.1 to 1.0 for the PC method and from 0.05 to 0.5 for the PP method. In order to obtain the nanoparticles, the precursors were heat treated at 500 and 800 °C. The thermal characterization of the precursor gels was carried out by thermogravimetric analysis (TGA) and the structural and morphological characterization by X-ray diffraction (XRD) and transmission electron microscopy (TEM). The XRD patterns of the samples obtained by both methods shows the formation of HfO2 at 500 °C with monoclinic crystalline phase. The PC method exhibited also the cubic phase. Finally, the HfO2 nanoparticles size (4 to 11 nm) was determined by TEM and XRD patterns. © (2010) Trans Tech Publications.

  5. Study of hafnium (IV) oxide nanoparticles synthesized by polymerized complex and polymer precursor derived sol-gel methods

    KAUST Repository

    Ramos-González, R.

    2010-03-01

    This work reports the preparation and characterization of hafnium (IV) oxide (HfO2) nanoparticles grown by derived sol-gel routes that involves the formation of an organic polymeric network. A comparison between polymerized complex (PC) and polymer precursor (PP) methods is presented. For the PC method, citric acid (CA) and ethylene glycol (EG) are used as the chelating and polymerizable reagents, respectively. In the case of PP method, poly(acrylic acid) (PAA) is used as the chelating reagent. In both cases, different precursor gels were prepared and the hafnium (IV) chloride (HfCl4) molar ratio was varied from 0.1 to 1.0 for the PC method and from 0.05 to 0.5 for the PP method. In order to obtain the nanoparticles, the precursors were heat treated at 500 and 800 °C. The thermal characterization of the precursor gels was carried out by thermogravimetric analysis (TGA) and the structural and morphological characterization by X-ray diffraction (XRD) and transmission electron microscopy (TEM). The XRD patterns of the samples obtained by both methods shows the formation of HfO2 at 500 °C with monoclinic crystalline phase. The PC method exhibited also the cubic phase. Finally, the HfO2 nanoparticles size (4 to 11 nm) was determined by TEM and XRD patterns. © (2010) Trans Tech Publications.

  6. 46 CFR 154.1200 - Mechanical ventilation system: General.

    Science.gov (United States)

    2010-10-01

    ... 46 Shipping 5 2010-10-01 2010-10-01 false Mechanical ventilation system: General. 154.1200 Section... CARGOES SAFETY STANDARDS FOR SELF-PROPELLED VESSELS CARRYING BULK LIQUEFIED GASES Design, Construction and Equipment Cargo Area: Mechanical Ventilation System § 154.1200 Mechanical ventilation system: General. (a...

  7. 46 CFR 154.1205 - Mechanical ventilation system: Standards.

    Science.gov (United States)

    2010-10-01

    ... 46 Shipping 5 2010-10-01 2010-10-01 false Mechanical ventilation system: Standards. 154.1205... CARGOES SAFETY STANDARDS FOR SELF-PROPELLED VESSELS CARRYING BULK LIQUEFIED GASES Design, Construction and Equipment Cargo Area: Mechanical Ventilation System § 154.1205 Mechanical ventilation system: Standards. (a...

  8. Rapid formation of nanocrystalline HfO2 powders from amorphous hafnium hydroxide under ultrasonically assisted hydrothermal treatment

    International Nuclear Information System (INIS)

    Meskin, Pavel E.; Sharikov, Felix Yu.; Ivanov, Vladimir K.; Churagulov, Bulat R.; Tretyakov, Yury D.

    2007-01-01

    Peculiarities of hafnium hydroxide hydrothermal decomposition were studied by in situ heat flux calorimetry for the first time. It was shown that this process occurs in one exothermal stage (ΔH = -17.95 kJ mol -1 ) at 180-250 deg. C resulting in complete crystallization of amorphous phase with formation of pure monoclinic HfO 2 . It was found that the rate of m-HfO 2 formation can be significantly increased by combining hydrothermal treatment with simultaneous ultrasonic activation

  9. 46 CFR 154.176 - Longitudinal contiguous hull structure.

    Science.gov (United States)

    2010-10-01

    ... 46 Shipping 5 2010-10-01 2010-10-01 false Longitudinal contiguous hull structure. 154.176 Section... Equipment Hull Structure § 154.176 Longitudinal contiguous hull structure. (a) The longitudinal contiguous hull structure of a vessel having cargo containment systems without secondary barriers must meet the...

  10. 46 CFR 154.174 - Transverse contiguous hull structure.

    Science.gov (United States)

    2010-10-01

    ... 46 Shipping 5 2010-10-01 2010-10-01 false Transverse contiguous hull structure. 154.174 Section... Equipment Hull Structure § 154.174 Transverse contiguous hull structure. (a) The transverse contiguous hull...) The transverse contiguous hull structure of a vessel having cargo containment systems with secondary...

  11. Improvement of aging kinetics and precipitate size refinement in Mg–Sn alloys by hafnium additions

    Energy Technology Data Exchange (ETDEWEB)

    Behdad, S. [Department of Mechanical and Materials Engineering, Florida International University, Miami, FL 33174 (United States); Zhou, L. [Department of Materials Science and Engineering and Advanced Materials Processing and Analysis Center, University of Central Florida, Orlando, FL 32816 (United States); Henderson, H.B.; Manuel, M.V. [Department of Materials Science and Engineering, University of Florida, Gainesville, FL 32611 (United States); Sohn, Y. [Department of Materials Science and Engineering and Advanced Materials Processing and Analysis Center, University of Central Florida, Orlando, FL 32816 (United States); Agarwal, A. [Department of Mechanical and Materials Engineering, Florida International University, Miami, FL 33174 (United States); Boesl, B., E-mail: bboesl@fiu.edu [Department of Mechanical and Materials Engineering, Florida International University, Miami, FL 33174 (United States)

    2016-01-10

    Two Mg–Sn alloys were microalloyed by addition of Hafnium and their age-hardening response was studied at 200 °C. Time to reach peak hardness was significantly reduced and improved by Hf addition. TEM study showed Hf clusters in the close vicinity and at the surface of Mg{sub 2}Sn precipitates, which confirms that Hf clusters act as additional nucleation centers for Mg{sub 2}Sn precipitate formation. Our results support the validity of thermokinetic criterion proposed by Mendis for selection of microalloying elements in order to refine precipitate size, accelerate aging kinetics and enhance peak hardness.

  12. 40 CFR 421.333 - Effluent limitations guidelines representing the degree of effluent reduction attainable by the...

    Science.gov (United States)

    2010-07-01

    ... 2.387 1.108 Nickel 4.688 3.154 Ammonia (as N) 1,136.000 499.500 (d) SiCl4 purification wet air... air pollution control. BAT Limitations for the Primary Zirconium and Hafnium Subcategory Pollutant or... 0.159 0.074 Nickel 0.312 0.210 Ammonia (as N) 75.710 33.280 (b) Sand chlorination off-gas wet air...

  13. Reduced lentivirus susceptibility in sheep with TMEM154 mutations.

    Science.gov (United States)

    Heaton, Michael P; Clawson, Michael L; Chitko-Mckown, Carol G; Leymaster, Kreg A; Smith, Timothy P L; Harhay, Gregory P; White, Stephen N; Herrmann-Hoesing, Lynn M; Mousel, Michelle R; Lewis, Gregory S; Kalbfleisch, Theodore S; Keen, James E; Laegreid, William W

    2012-01-01

    Visna/Maedi, or ovine progressive pneumonia (OPP) as it is known in the United States, is an incurable slow-acting disease of sheep caused by persistent lentivirus infection. This disease affects multiple tissues, including those of the respiratory and central nervous systems. Our aim was to identify ovine genetic risk factors for lentivirus infection. Sixty-nine matched pairs of infected cases and uninfected controls were identified among 736 naturally exposed sheep older than five years of age. These pairs were used in a genome-wide association study with 50,614 markers. A single SNP was identified in the ovine transmembrane protein (TMEM154) that exceeded genome-wide significance (unadjusted p-value 3×10(-9)). Sanger sequencing of the ovine TMEM154 coding region identified six missense and two frameshift deletion mutations in the predicted signal peptide and extracellular domain. Two TMEM154 haplotypes encoding glutamate (E) at position 35 were associated with infection while a third haplotype with lysine (K) at position 35 was not. Haplotypes encoding full-length E35 isoforms were analyzed together as genetic risk factors in a multi-breed, matched case-control design, with 61 pairs of 4-year-old ewes. The odds of infection for ewes with one copy of a full-length TMEM154 E35 allele were 28 times greater than the odds for those without (p-valuesheep from Nebraska, Idaho, and Iowa, the relative risk of infection was 2.85 times greater for sheep with a full-length TMEM154 E35 allele (p-valuesheep were homozygous for TMEM154 deletion mutations and remained uninfected despite a lifetime of significant exposure. Together, these findings indicate that TMEM154 may play a central role in ovine lentivirus infection and removing sheep with the most susceptible genotypes may help eradicate OPP and protect flocks from reinfection.

  14. Performance studies of varian VPM-154D.6D VPM-154A/1.6L static crossed field photomultipliers

    International Nuclear Information System (INIS)

    Lo, C.C.; Leskovar, B.

    1977-01-01

    Characteristics have been measured for the Varian VPM-154D.6D and VPM-154A/1.6L Static Crossed Field Photomultipliers. Some typical photomultiplier characteristics such as: gain, dark current, quantum efficiency, and rise-time--are compared with data provided by the manufacturer. Photomultiplier characteristics generally not available from the manufacturer, such as: transit time, FWHM of the output pulse, peak output current measurement and multiphotoelectron time resolution were measured and are discussed

  15. Solvent extraction of hafnium(IV) by dinonylnaphthalene sulfonic acid from mixed aqueous-organic media

    International Nuclear Information System (INIS)

    Hala, J.; Piperkovova, H.

    1979-01-01

    The extraction of hafnium(IV) by heptane and toluene solutions of dinonylnaphthalene sulfonic acid (HD) from mixed aqueous-organic solutions has been studied. Alcohols, ketones, carboxylic acids, cyclic ethers, dimethylsulfoxide and dimethylformamide were used as the organic component of the mixed phase. Methanol, ethanol, formic acid and dioxane increased the extractability of Hf(IV) whereas other solvents showed only an antagonistic effect. The results were discussed from the point of view of the changes in micellar structure of HD, and compared with the uptake of Hf(IV) by resinous cation exchangers. The solubilization by HD of alcohols, carboxylic acids and dimethylsulfoxide was demonstrated by using the corresponding 14 C and 35 S labelled compounds. (author)

  16. The interfacial orientation relationship of oxide nanoparticles in a hafnium-containing oxide dispersion-strengthened austenitic stainless steel

    Energy Technology Data Exchange (ETDEWEB)

    Miao, Yinbin, E-mail: miao2@illinois.edu [Department of Nuclear, Plasma and Radiological Engineering, University of Illinois at Urbana-Champaign, Urbana, IL 61801 (United States); Mo, Kun [Nuclear Engineering Division, Argonne National Laboratory, Lemont, IL 60493 (United States); Cui, Bai [Department of Mechanical and Materials Engineering, University of Nebraska-Lincoln, Lincoln, NE 68588 (United States); Department of Material Science and Engineering, University of Illinois at Urbana-Champaign, Urbana, IL 61801 (United States); Chen, Wei-Ying [Department of Nuclear, Plasma and Radiological Engineering, University of Illinois at Urbana-Champaign, Urbana, IL 61801 (United States); Miller, Michael K.; Powers, Kathy A. [Center for Nanophase Materials Sciences, Oak Ridge National Laboratory, Oak Ridge, TN 37830 (United States); McCreary, Virginia; Gross, David [Department of Material Science and Engineering, University of Illinois at Urbana-Champaign, Urbana, IL 61801 (United States); Almer, Jonathan [X-ray Science Division, Argonne National Laboratory, Lemont, IL 60493 (United States); Robertson, Ian M. [Department of Material Science and Engineering, University of Wisconsin-Madison, Madison, WA 53706 (United States); Department of Material Science and Engineering, University of Illinois at Urbana-Champaign, Urbana, IL 61801 (United States); Stubbins, James F. [Department of Nuclear, Plasma and Radiological Engineering, University of Illinois at Urbana-Champaign, Urbana, IL 61801 (United States)

    2015-03-15

    This work reports comprehensive investigations on the orientation relationship of the oxide nanoparticles in a hafnium-containing austenitic oxide dispersion-strengthened 316 stainless steel. The phases of the oxide nanoparticles were determined by a combination of scanning transmission electron microscopy–electron dispersive X-ray spectroscopy, atom probe tomography and synchrotron X-ray diffraction to be complex Y–Ti–Hf–O compounds with similar crystal structures, including bixbyite Y{sub 2}O{sub 3}, fluorite Y{sub 2}O{sub 3}–HfO{sub 2} solid solution and pyrochlore (or fluorite) Y{sub 2}(Ti,Hf){sub 2−x}O{sub 7−x}. High resolution transmission electron microscopy was used to characterize the particle–matrix interfaces. Two different coherency relationships along with one axis-parallel relation between the oxide nanoparticles and the steel matrix were found. The size of the nanoparticles significantly influences the orientation relationship. The results provide insight into the relationship of these nanoparticles with the matrix, which has implications for interpreting material properties as well as responses to radiation. - Highlights: • The oxide nanoparticles in a hafnium-containing austenitic ODS were characterized. • The nanoparticles are Y–Hf–Ti–O enriched phases according to APT and STEM–EDS. • Two coherency and an axis-parallel orientation relationships were found by HR-TEM. • Particle size has a prominent effect on the orientation relationship (OR). • Formation mechanism of the oxide nanoparticles was discussed based on the ORs.

  17. 32 CFR 154.40 - General.

    Science.gov (United States)

    2010-07-01

    ... PROGRAM REGULATION Adjudication § 154.40 General. (a) The standard which must be met for clearance or assignment to sensitive duties is that, based on all available information, the person's loyalty, reliability...

  18. Hafnium oxide nanoparticles: toward an in vitro predictive biological effect?

    International Nuclear Information System (INIS)

    Marill, Julie; Anesary, Naeemunnisa Mohamed; Zhang, Ping; Vivet, Sonia; Borghi, Elsa; Levy, Laurent; Pottier, Agnes

    2014-01-01

    Hafnium oxide, NBTXR3 nanoparticles were designed for high dose energy deposition within cancer cells when exposed to ionizing radiation. The purpose of this study was to assess the possibility of predicting in vitro the biological effect of NBTXR3 nanoparticles when exposed to ionizing radiation. Cellular uptake of NBTXR3 nanoparticles was assessed in a panel of human cancer cell lines (radioresistant and radiosensitive) by transmission electron microscopy. The radioenhancement of NBTXR3 nanoparticles was measured by the clonogenic survival assay. NBTXR3 nanoparticles were taken up by cells in a concentration dependent manner, forming clusters in the cytoplasm. Differential nanoparticle uptake was observed between epithelial and mesenchymal or glioblastoma cell lines. The dose enhancement factor increased with increase NBTXR3 nanoparticle concentration and radiation dose. Beyond a minimum number of clusters per cell, the radioenhancement of NBTXR3 nanoparticles could be estimated from the radiation dose delivered and the radiosensitivity of the cancer cell lines. Our preliminary results suggest a predictable in vitro biological effect of NBTXR3 nanoparticles exposed to ionizing radiation

  19. Reduced lentivirus susceptibility in sheep with TMEM154 mutations.

    Directory of Open Access Journals (Sweden)

    Michael P Heaton

    2012-01-01

    Full Text Available Visna/Maedi, or ovine progressive pneumonia (OPP as it is known in the United States, is an incurable slow-acting disease of sheep caused by persistent lentivirus infection. This disease affects multiple tissues, including those of the respiratory and central nervous systems. Our aim was to identify ovine genetic risk factors for lentivirus infection. Sixty-nine matched pairs of infected cases and uninfected controls were identified among 736 naturally exposed sheep older than five years of age. These pairs were used in a genome-wide association study with 50,614 markers. A single SNP was identified in the ovine transmembrane protein (TMEM154 that exceeded genome-wide significance (unadjusted p-value 3×10(-9. Sanger sequencing of the ovine TMEM154 coding region identified six missense and two frameshift deletion mutations in the predicted signal peptide and extracellular domain. Two TMEM154 haplotypes encoding glutamate (E at position 35 were associated with infection while a third haplotype with lysine (K at position 35 was not. Haplotypes encoding full-length E35 isoforms were analyzed together as genetic risk factors in a multi-breed, matched case-control design, with 61 pairs of 4-year-old ewes. The odds of infection for ewes with one copy of a full-length TMEM154 E35 allele were 28 times greater than the odds for those without (p-value<0.0001, 95% CI 5-1,100. In a combined analysis of nine cohorts with 2,705 sheep from Nebraska, Idaho, and Iowa, the relative risk of infection was 2.85 times greater for sheep with a full-length TMEM154 E35 allele (p-value<0.0001, 95% CI 2.36-3.43. Although rare, some sheep were homozygous for TMEM154 deletion mutations and remained uninfected despite a lifetime of significant exposure. Together, these findings indicate that TMEM154 may play a central role in ovine lentivirus infection and removing sheep with the most susceptible genotypes may help eradicate OPP and protect flocks from reinfection.

  20. 46 CFR 154.178 - Contiguous hull structure: Heating system.

    Science.gov (United States)

    2010-10-01

    ... 46 Shipping 5 2010-10-01 2010-10-01 false Contiguous hull structure: Heating system. 154.178... Equipment Hull Structure § 154.178 Contiguous hull structure: Heating system. The heating system for transverse and longitudinal contiguous hull structure must: (a) Be shown by a heat load calculation to have...

  1. 24 CFR 9.154 - Occupancy of accessible dwelling units.

    Science.gov (United States)

    2010-04-01

    ... 24 Housing and Urban Development 1 2010-04-01 2010-04-01 false Occupancy of accessible dwelling units. 9.154 Section 9.154 Housing and Urban Development Office of the Secretary, Department of Housing... dwelling units. (a) The agency shall adopt suitable means to assure that information regarding the...

  2. Nano-scale Radiotherapy-NBTXR3 Hafnium Oxide Nanoparticles as Promising Cancer Therapy

    International Nuclear Information System (INIS)

    Maggiorella, L.; Barouch, G.; Devaux, C.; Pottier, A.; Levy, L.; Deutsch, E.; Bourhis, J.; Borghi, E.

    2011-01-01

    Complete text of publication follows: Background: There is considerable interest in approaches that could improve the therapeutic window of radiotherapy, which represents a crucial modality of treatment in oncology. We present the rationale for designing NBTXR3 nanoparticles activated by radiotherapy and validate the concept. We performed the Monte Carlo calculations for the first time based on the 'local model' simulation that showed a dose enhancement of radiation to tumour cells of approximately nine-fold. NBTXR3 was shown to deposit high energy when the ionizing radiation source is 'on' and to have chemically inert behavior in cellular and subcellular systems demonstrated by very good systemic tolerance, thus decreasing potential health hazards. Material and Methods: We used conventional methods, implemented in different ways, to explore interactions of high Z matter and ionizing radiation with biological systems. In addition, microtomography was performed to explore the nanoparticle volume occupancy inside the tumour and its persistence overtime in mouse tumour models. The antitumour activity of NBTXR3 and tolerance were evaluated in Ewing tumour (A673) and fibrosarcoma (HT1080) using high energy source. Results and Conclusion: We created and developed NBTXR3 nanoparticles with a crystalline hafnium oxide core which provide high electron density structure and inert behavior in biological media. NBTXR3 nanoparticles' characteristics, size, charge and shape, allow for efficient interaction with biological entities, cell membrane binding and cellular uptake. The nanoparticles were shown to form clusters at the subcellular level in tumour models. Of most importance, we show NBTXR3 intra-tumour bioavailability with dispersion of nanoparticles in the three dimensions and persistence within the tumour structure, supporting the use of NBTXR3 as effective antitumour therapeutic agent. Antitumour activity of NBTXR3 showed marked advantage in terms of survival, tumour

  3. A fast response hafnium selective polymeric membrane electrode based on N,N'-bis({alpha}-methyl-salicylidene)-dipropylenetriamine as a neutral carrier

    Energy Technology Data Exchange (ETDEWEB)

    Rezaei, B. [Department of Chemistry, Isfahan University of Technology, Isfahan 84156-83111 (Iran, Islamic Republic of)], E-mail: rezaei@cc.iut.ac.ir; Meghdadi, S.; Zarandi, R. Fazel [Department of Chemistry, Isfahan University of Technology, Isfahan 84156-83111 (Iran, Islamic Republic of)

    2008-08-30

    In this study a new hafnium selective sensor was fabricated from polyvinylchloride (PVC) matrix membrane containing neutral carrier N,N'-bis({alpha}-methyl-salicylidene)-dipropylenetriamine (Mesaldpt) as a new ionophore, sodium tetraphenyl borate (NaTPB) as anionic discriminator and dioctyl phthalate (DOP) as plasticizing solvent mediator in tetrahydrofuran solvent. The electrode exhibits Nernstian response for Hf{sup 4+} (Hafnium(IV)) over a wide concentration range (2.0 x 10{sup -7} to 1.0 x 10{sup -1} M) with the determination coefficient of 0.9966 and slope of 15.1 {+-} 0.1 mV decades{sup -1}. The limit of detection is 1.9 x 10{sup -7} M. The electrode has a fast response time of 18 s and a working pH range of 4-8. The proposed membrane shows excellent discriminating ability towards Hf{sup 4+} ion with regard to several alkali, alkaline earth transition and heavy metal ions. It can be used over a period of 1.5 months with good reproducibility. It is successfully applied for direct determination of Hf{sup 4+} in solutions by standard addition method for real sample analysis.

  4. Hafnium-doped hydroxyapatite nanoparticles with ionizing radiation for lung cancer treatment.

    Science.gov (United States)

    Chen, Min-Hua; Hanagata, Nobutaka; Ikoma, Toshiyuki; Huang, Jian-Yuan; Li, Keng-Yuan; Lin, Chun-Pin; Lin, Feng-Huei

    2016-06-01

    Recently, photodynamic therapy (PDT) is one of the new clinical options by generating cytotoxic reactive oxygen species (ROS) to kill cancer cells. However, the optical approach of PDT is limited by tissue penetration depth of visible light. In this study, we propose that a ROS-enhanced nanoparticle, hafnium-doped hydroxyapatite (Hf:HAp), which is a material to yield large quantities of ROS inside the cells when the nanoparticles are bombarded with high penetrating power of ionizing radiation. Hf:HAp nanoparticles are generated by wet chemical precipitation with total doping concentration of 15mol% Hf(4+) relative to Ca(2+) in HAp host material. The results show that the HAp particles could be successfully doped with Hf ions, resulted in the formation of nano-sized rod-like shape and with pH-dependent solubility. The impact of ionizing radiation on Hf:HAp nanoparticles is assessed by using in-vitro and in-vivo model using A549 cell line. The 2',7'-dichlorofluorescein diacetate (DCFH-DA) results reveal that after being exposed to gamma rays, Hf:HAp could significantly lead to the formation of ROS in cells. Both cell viability (WST-1) and cytotoxicity (LDH) assay show the consistent results that A549 lung cancer cell lines are damaged with changes in the cells' ROS level. The in-vivo studies further demonstrate that the tumor growth is inhibited owing to the cells apoptosis when Hf:HAp nanoparticles are bombarded with ionizing radiation. This finding offer a new therapeutic method of interacting with ionizing radiation and demonstrate the potential of Hf:HAp nanoparticles in tumor treatment, such as being used in a palliative treatment after lung surgical procedure. Photodynamic therapy (PDT) is one of the new clinical options by generating cytotoxic reactive oxygen species (ROS) to kill cancer cells. Unfortunately, the approach of PDT is usually limited to the treatment of systemic disease and deeper tumor, due to the limited tissue penetration depth of visible

  5. Requirement of transmembrane domain for CD154 association to lipid rafts and subsequent biological events.

    Directory of Open Access Journals (Sweden)

    Nadir Benslimane

    Full Text Available Interaction of CD40 with CD154 leads to recruitment of both molecules into lipid rafts, resulting in bi-directional cell activation. The precise mechanism by which CD154 is translocated into lipid rafts and its impact on CD154 signaling remain largely unknown. Our aim is to identify the domain of CD154 facilitating its association to lipid rafts and the impact of such association on signaling events and cytokine production. Thus, we generated Jurkat cell lines expressing truncated CD154 lacking the cytoplasmic domain or chimeric CD154 in which the transmembrane domain was replaced by that of transferrin receptor I, known to be excluded from lipid rafts. Our results show that cell stimulation with soluble CD40 leads to the association of CD154 wild-type and CD154-truncated, but not CD154-chimera, with lipid rafts. This is correlated with failure of CD154-chimera to activate Akt and p38 MAP kinases, known effectors of CD154 signaling. We also found that CD154-chimera lost the ability to promote IL-2 production upon T cell stimulation with anti-CD3/CD28 and soluble CD40. These results demonstrate the implication of the transmembrane domain of CD154 in lipid raft association, and that this association is necessary for CD154-mediated Akt and p38 activation with consequent enhancement of IL-2 production.

  6. 46 CFR 154.195 - Aluminum cargo tank: Steel enclosure.

    Science.gov (United States)

    2010-10-01

    ... 46 Shipping 5 2010-10-01 2010-10-01 false Aluminum cargo tank: Steel enclosure. 154.195 Section... Equipment Hull Structure § 154.195 Aluminum cargo tank: Steel enclosure. (a) An aluminum cargo tank and its... the aluminum cargo tank must meet the steel structural standards of the American Bureau of Shipping...

  7. 46 CFR 154.180 - Contiguous hull structure: Welding procedure.

    Science.gov (United States)

    2010-10-01

    ... 46 Shipping 5 2010-10-01 2010-10-01 false Contiguous hull structure: Welding procedure. 154.180... Equipment Hull Structure § 154.180 Contiguous hull structure: Welding procedure. Welding procedure tests for contiguous hull structure designed for a temperature colder than −18 °C (0 °F) must meet § 54.05-15 and...

  8. 32 CFR 154.3 - Definitions.

    Science.gov (United States)

    2010-07-01

    ..., National Security Agency/Central Security Service; Director, Defense Intelligence Agency; Assistant Chief... Defense Department of Defense OFFICE OF THE SECRETARY OF DEFENSE SECURITY DEPARTMENT OF DEFENSE PERSONNEL SECURITY PROGRAM REGULATION General Provisions § 154.3 Definitions. (a) Access. The ability and opportunity...

  9. Genetic Testing for TMEM154 Mutations Associated with Lentivirus Susceptibility in Sheep

    Science.gov (United States)

    Petrik, Dustin T.; Simpson, Barry; Kijas, James W.; Clawson, Michael L.; Chitko-McKown, Carol G.; Harhay, Gregory P.; Leymaster, Kreg A.

    2013-01-01

    In sheep, small ruminant lentiviruses cause an incurable, progressive, lymphoproliferative disease that affects millions of animals worldwide. Known as ovine progressive pneumonia virus (OPPV) in the U.S., and Visna/Maedi virus (VMV) elsewhere, these viruses reduce an animal’s health, productivity, and lifespan. Genetic variation in the ovine transmembrane protein 154 gene (TMEM154) has been previously associated with OPPV infection in U.S. sheep. Sheep with the ancestral TMEM154 haplotype encoding glutamate (E) at position 35, and either form of an N70I variant, were highly-susceptible compared to sheep homozygous for the K35 missense mutation. Our current overall aim was to characterize TMEM154 in sheep from around the world to develop an efficient genetic test for reduced susceptibility. The average frequency of TMEM154 E35 among 74 breeds was 0.51 and indicated that highly-susceptible alleles were present in most breeds around the world. Analysis of whole genome sequences from an international panel of 75 sheep revealed more than 1,300 previously unreported polymorphisms in a 62 kb region containing TMEM154 and confirmed that the most susceptible haplotypes were distributed worldwide. Novel missense mutations were discovered in the signal peptide (A13V) and the extracellular domains (E31Q, I74F, and I102T) of TMEM154. A matrix-assisted laser desorption/ionization–time-of flight mass spectrometry (MALDI-TOF MS) assay was developed to detect these and six previously reported missense and two deletion mutations in TMEM154. In blinded trials, the call rate for the eight most common coding polymorphisms was 99.4% for 499 sheep tested and 96.0% of the animals were assigned paired TMEM154 haplotypes (i.e., diplotypes). The widespread distribution of highly-susceptible TMEM154 alleles suggests that genetic testing and selection may improve the health and productivity of infected flocks. PMID:23408992

  10. Genetic testing for TMEM154 mutations associated with lentivirus susceptibility in sheep.

    Directory of Open Access Journals (Sweden)

    Michael P Heaton

    Full Text Available In sheep, small ruminant lentiviruses cause an incurable, progressive, lymphoproliferative disease that affects millions of animals worldwide. Known as ovine progressive pneumonia virus (OPPV in the U.S., and Visna/Maedi virus (VMV elsewhere, these viruses reduce an animal's health, productivity, and lifespan. Genetic variation in the ovine transmembrane protein 154 gene (TMEM154 has been previously associated with OPPV infection in U.S. sheep. Sheep with the ancestral TMEM154 haplotype encoding glutamate (E at position 35, and either form of an N70I variant, were highly-susceptible compared to sheep homozygous for the K35 missense mutation. Our current overall aim was to characterize TMEM154 in sheep from around the world to develop an efficient genetic test for reduced susceptibility. The average frequency of TMEM154 E35 among 74 breeds was 0.51 and indicated that highly-susceptible alleles were present in most breeds around the world. Analysis of whole genome sequences from an international panel of 75 sheep revealed more than 1,300 previously unreported polymorphisms in a 62 kb region containing TMEM154 and confirmed that the most susceptible haplotypes were distributed worldwide. Novel missense mutations were discovered in the signal peptide (A13V and the extracellular domains (E31Q, I74F, and I102T of TMEM154. A matrix-assisted laser desorption/ionization-time-of flight mass spectrometry (MALDI-TOF MS assay was developed to detect these and six previously reported missense and two deletion mutations in TMEM154. In blinded trials, the call rate for the eight most common coding polymorphisms was 99.4% for 499 sheep tested and 96.0% of the animals were assigned paired TMEM154 haplotypes (i.e., diplotypes. The widespread distribution of highly-susceptible TMEM154 alleles suggests that genetic testing and selection may improve the health and productivity of infected flocks.

  11. Sub-10 nm low current resistive switching behavior in hafnium oxide stack

    Energy Technology Data Exchange (ETDEWEB)

    Hou, Y., E-mail: houyi@pku.edu.cn, E-mail: lfliu@pku.edu.cn [Institute of Microelectronics, Peking University, 100871 Beijing (China); IMEC, Kapeldreef 75, B-3001 Heverlee (Belgium); Department of Physics and Astronomy, KU Leuven, Celestijnenlaan 200D, B-3001 Heverlee (Belgium); Celano, U.; Xu, Z.; Vandervorst, W. [IMEC, Kapeldreef 75, B-3001 Heverlee (Belgium); Department of Physics and Astronomy, KU Leuven, Celestijnenlaan 200D, B-3001 Heverlee (Belgium); Goux, L.; Fantini, A.; Degraeve, R.; Youssef, A.; Jurczak, M. [IMEC, Kapeldreef 75, B-3001 Heverlee (Belgium); Liu, L., E-mail: houyi@pku.edu.cn, E-mail: lfliu@pku.edu.cn; Cheng, Y.; Kang, J. [Institute of Microelectronics, Peking University, 100871 Beijing (China)

    2016-03-21

    In this letter, a tip-induced cell relying on the conductive atomic force microscope is proposed. It is verified as a referable replica of an integrated resistive random access memory (RRAM) device. On the basis of this cell, the functionality of sub-10 nm resistive switching is confirmed in hafnium oxide stack. Moreover, the low current switching behavior in the sub-10 nm dimension is found to be more pronounced than that of a 50 × 50 nm{sup 2} device. It shows better ON/OFF ratio and low leakage current. The enhanced memory performance is ascribed to a change in the shape of the conductive filament as the device dimensions are reduced to sub-10 nm. Therefore, device downscaling provides a promising approach for the resistance optimization that benefits the RRAM array design.

  12. 33 CFR 154.1010 - Purpose.

    Science.gov (United States)

    2010-07-01

    ... FACILITIES TRANSFERRING OIL OR HAZARDOUS MATERIAL IN BULK Response Plans for Oil Facilities § 154.1010 Purpose. This subpart establishes oil spill response plan requirements for all marine transportation... response plan prepares the facility owner or operator to respond to an oil spill. These requirements...

  13. 46 CFR 154.459 - General.

    Science.gov (United States)

    2010-10-01

    ..., DEPARTMENT OF HOMELAND SECURITY (CONTINUED) CERTAIN BULK DANGEROUS CARGOES SAFETY STANDARDS FOR SELF-PROPELLED VESSELS CARRYING BULK LIQUEFIED GASES Design, Construction and Equipment Secondary Barrier § 154.459 General. (a) Each cargo tank must have a secondary barrier that meets Table 3 and except as...

  14. 7 CFR 1900.154 - Determining the need for special handling.

    Science.gov (United States)

    2010-01-01

    ... 7 Agriculture 12 2010-01-01 2010-01-01 false Determining the need for special handling. 1900.154 Section 1900.154 Agriculture Regulations of the Department of Agriculture (Continued) RURAL HOUSING SERVICE, RURAL BUSINESS-COOPERATIVE SERVICE, RURAL UTILITIES SERVICE, AND FARM SERVICE AGENCY, DEPARTMENT...

  15. 29 CFR 15.4 - Administrative claim; where to file.

    Science.gov (United States)

    2010-07-01

    ... accompanied by a claim for money damages in a sum certain for injury to or loss of property or personal injury... hereunder to the Council for Claims and Compensation, Office of the Solicitor of Labor, U.S. Department of... 29 Labor 1 2010-07-01 2010-07-01 true Administrative claim; where to file. 15.4 Section 15.4 Labor...

  16. Separation of hafnium from zirconium in their tetrachloride solution in molten alkali metal chlorides

    Energy Technology Data Exchange (ETDEWEB)

    Salyulev, A B; Kudyakov, V Ya; Smirnov, M V; Moskalenko, N I [AN SSSR, Sverdlovsk. Inst. Ehlektrokhimii

    1984-08-01

    The coefficient of HfCl/sub 4/ and ZrCl/sub 4/ separation in the process of vapour sublimation from their solutions in molten NaCl, KCl, CsCl, NaCl-KCl and NaCl-CsCl equimolar mixtures is found to vary in the series from approximately 1.10 to approximately 1.22 and practically not to depend on the temperature (in the 600-910 deg) range and concentration (2-25 mol.% ZrCl/sub 4/+HfCl/sub 4/). HfCl/sub 4/ and ZrCl/sub 4/ are shown to form almost perfect solutions with each other, which in their turn form imperfect solutions with molten alkali metal chlorides, with the strength of hafnium complex chloride anions increasing higher than that of zirconium in the series from NaCl to CsCl.

  17. Separation of hafnium from zirconium in their tetrachloride solution in molten alkali metal chlorides

    International Nuclear Information System (INIS)

    Salyulev, A.B.; Kudyakov, V.Ya.; Smirnov, M.V.; Moskalenko, N.I.

    1984-01-01

    The coefficient of HfCl 4 and ZrCl 4 separation in the process of vapour sublimation from their solutions in molten NaCl, KCl, CsCl, NaCl-KCl and NaCl-CsCl equimolar mixtures is found to vary in the series from approximately 1.10 to approximately 1.22 and practically not to depend on the temperature (in the 600-910 deg) range and concentration (2-25 mol.% ZrCl 4 +HfCl 4 ). HfCl 4 and ZrCl 4 are shown to form almost perfect solutions with each other, which in their turn form imperfect solutions with molten alkali metal chlorides, with the strength of hafnium complex chloride anions increasing higher than that of zirconium in the series from NaCl to CsCl

  18. Level structure of 154Ho

    Science.gov (United States)

    Moon, Chang-Bum; Komatsubara, Tetsuro; Furuno, Kohei

    2013-10-01

    The excited states of the odd-odd 154Ho nucleus have been studied by using in-beam γ-ray spectroscopy with the 141Pr (16O, 3n) 154Ho reaction at Elab=75 MeV. The beam was provided by the 12UD Pelletron accelerator at the University of Tsukuba. In this work, the complicated decay pattern of low energy transitions just above the T1/2=3.10 min isomer have been established. In addition, a number of new states and γ-ray transitions, especially those associated with energetically favored band termination, have been observed for the first time in 154Ho. A negative collective band and its signature partner built on the 11- level are interpreted as being based on the πh11/2⊗νi13/2 configuration. A positive band built on the 10+ level is based on the πh11/2⊗νh9/2 configuration while another positive band built on the 9+ level is being associated with the πh11/2⊗νf7/2 configuration. An energetically favored level Jπ=19- can be interpreted as being attributed to the πh11/2⊗νi13/2 configuration coupled to the 8+ state in neighboring core 152Dy, namely, a four-quasiparticle alignment based on the [πh11/2νi13/2]11-⊗[ν(h9/2f7/2)]8- configuration. Another energetically favored state at Jπ=27- is assigned the six-quasiparticle [π(h11/2)3]27/2-⊗[ν(f7/2h9/2i13/2)]27/2- configuration.

  19. 40 CFR 154.7 - Criteria for initiation of Special Review.

    Science.gov (United States)

    2010-07-01

    ... methods of evaluating data and relating such data to human risk. (3) May result in residues in the... Review. 154.7 Section 154.7 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED... risk of serious acute injury to humans or domestic animals. (2) May pose a risk of inducing in humans...

  20. 46 CFR 154.1730 - Ethylene oxide: Loading and off loading.

    Science.gov (United States)

    2010-10-01

    ... 46 Shipping 5 2010-10-01 2010-10-01 false Ethylene oxide: Loading and off loading. 154.1730... Operating Requirements § 154.1730 Ethylene oxide: Loading and off loading. (a) The master shall ensure that before ethylene oxide is loaded into a cargo tank: (1) The tank is thoroughly clean, dry, and free of...

  1. Density and surface tension of melts of zirconium and hafnium fluorides with lithium fluoride

    International Nuclear Information System (INIS)

    Katyshev, S.F.; Artemov, V.V.; Desyatnik, V.N.

    1988-01-01

    A study was conducted to determine the temperature dependence of the density and surface tension of melts of LiF-ZrF 4 and LiF-HfF 4 . Density and surface tension were determined by the method of maximum pressure in an argon bubble. On the basis of experimental data over the entire concentration range the molar volumes and their relative deviations from the additive molar volumes were calculated for 1100 0 K. The positive deviations of the molar volumes from additivity in the LiF-HfF 4 system (22.45%) were greater than in the LiF-ZrF 4 system (15.75%). This indicated that the reaction with lithium fluoride is intensified with the switch to the hafnium fluoride. Results also demonstrated that the fluorides are surface-active components in the molten mixtures

  2. 46 CFR 154.182 - Contiguous hull structure: Production weld test.

    Science.gov (United States)

    2010-10-01

    ... 46 Shipping 5 2010-10-01 2010-10-01 false Contiguous hull structure: Production weld test. 154.182... Equipment Hull Structure § 154.182 Contiguous hull structure: Production weld test. If a portion of the contiguous hull structure is designed for a temperature colder than −34 °C (−30 °F) and is not part of the...

  3. 46 CFR 154.448 - Calculations.

    Science.gov (United States)

    2010-10-01

    ... element analysis using the loads determined under § 154.406. (f) A fracture mechanics analysis using the... formula: EC02FE91.088 where: ni=the number of stress cycles at each stress level during the life of the vessel; Ni=the number of cycles to failure for corresponding stress levels from the Wohler (S-N) curve...

  4. Tribo-electrochemical characterization of hafnium multilayer systems deposited on nitride/vanadium nitride AISI 4140 steel

    Science.gov (United States)

    Mora, M.; Vera, E.; Aperador, W.

    2016-02-01

    In this work is presented the synergistic behaviour among corrosion/wear (tribocorrosion) of the multilayer coatings hafnium nitride/vanadium nitride [HfN/VN]n. The multilayers were deposited on AISI 4140 steel using the technique of physical vapor deposition PVD magnetron sputtering, the tests were performed using a pin-on-disk tribometer, which has an adapted potentiostat galvanostat with three-electrode electrochemical cell. Tribocorrosive parameters such as: Friction coefficient between the coating and the counter body (100 Cr6 steel ball); Polarization resistance by means of electrochemical impedance spectroscopy technique and corrosion rate by polarization curves were determined. It was observed an increase in the polarization resistance, a decrease in the corrosion rate and a low coefficient of friction in comparison with the substrate, due to an increase on the number of bilayers.

  5. Tribo-electrochemical characterization of hafnium multilayer systems deposited on nitride/vanadium nitride AISI 4140 steel

    International Nuclear Information System (INIS)

    Mora, M; Vera, E; Aperador, W

    2016-01-01

    In this work is presented the synergistic behaviour among corrosion/wear (tribocorrosion) of the multilayer coatings hafnium nitride/vanadium nitride [HfN/VN]n. The multilayers were deposited on AISI 4140 steel using the technique of physical vapor deposition PVD magnetron sputtering, the tests were performed using a pin-on-disk tribometer, which has an adapted potentiostat galvanostat with three-electrode electrochemical cell. Tribocorrosive parameters such as: Friction coefficient between the coating and the counter body (100 Cr6 steel ball); Polarization resistance by means of electrochemical impedance spectroscopy technique and corrosion rate by polarization curves were determined. It was observed an increase in the polarization resistance, a decrease in the corrosion rate and a low coefficient of friction in comparison with the substrate, due to an increase on the number of bilayers. (paper)

  6. Rapid screening of nuclear grade zirconium silicate without separation of hafnium from the bulk matrix

    International Nuclear Information System (INIS)

    Venkatesh, Manisha; Sharma, P.K.; Avhad, D.K.; Basu, H.; Singhal, R.K.; Reddy, A.V.R.

    2014-01-01

    Zirconium silicate, also zirconium orthosilicate, (ZrSiO 4 ) is a chemical compound, and occurs in nature as zircon, a silicate mineral. The concentration of Hafnium in nuclear grade Zirconium must be less than 0.2% w/w of Zr. In view of this it must be accurately chemically characterized before issuing a certification for export under non nuclear category. As the chemistry of Zr and Hf is similar, it is difficult to separate Hf by direct wet chemical method. During this work, concentration of Hf in zirconium silicate was measured by Field Portable X-ray Fluorescence (FPXRF) and results obtained were validated by using detailed chemical method. FPXRF spectrometry has become a common analytical technique for on-site screening and fast turnaround analysis of contaminant elements in environmental samples

  7. Unexpected structure in the E2 quasicontinuum spectrum of 154Dy

    International Nuclear Information System (INIS)

    Holzmann, R.; Khoo, T.L.; Ma, W.C.

    1988-01-01

    The evolution of the γ quasicontinuum spectrum with neutron number has been investigated in the sequence of dysprosium isotopes /sup 152,154,156/Dy. The three nuclei display a pronounced collective E2 component. In 154 Dy this component shows an unexpected splitting into two distinct parts, signifying a structural change along the γ cascade. The E2 and statistical components can be reproduced in simple γ cascade calculations; in 152 Dy and 156 Dy only rotational bands were included, whereas in 154 Dy additional vibration-like transitions were required to reproduce the two E2 peaks. 11 refs., 2 figs

  8. 46 CFR 154.1720 - Indirect refrigeration.

    Science.gov (United States)

    2010-10-01

    ... Shipping COAST GUARD, DEPARTMENT OF HOMELAND SECURITY (CONTINUED) CERTAIN BULK DANGEROUS CARGOES SAFETY STANDARDS FOR SELF-PROPELLED VESSELS CARRYING BULK LIQUEFIED GASES Special Design and Operating Requirements § 154.1720 Indirect refrigeration. A refrigeration system that is used to cool acetaldehyde, ethylene...

  9. Identification of new negative-parity levels in 152,154Nd

    International Nuclear Information System (INIS)

    Zhang, X.Q.; Hamilton, J.H.; Ramayya, A.V.; Peker, L.K.; Hwang, J.K.; Jones, E.F.; Komicki, J.; Beyer, C.J.; Gore, P.M.; Babu, B.R.; Ginter, T.N.; Ter-Akopian, G.M.; Daniel, A.V.; Asztalos, S.J.; Chu, S.Y.; Gregorich, K.E.; Lee, I.Y.; Macchiavelli, A.O.; Macleod, R.W.; Rasmussen, J.O.; Gilat, J.; Ter-Akopian, G.M.; Oganessian, Y.T.; Daniel, A.V.; Ter-Akopian, G.M.; Daniel, A.V.; Ma, W.C.; Varmette, P.G.; Cole, J.D.; Aryaeinejad, R.; Butler-Moore, K.; Dardenne, Y.X.; Drigert, M.W.; Stoyer, M.A.; Wild, J.F.; Becker, J.A.; Bernstein, L.A.; Lougheed, R.W.; Moody, K.J.; Donangelo, R.; Prussin, S.G.; Griffin, H.C.

    1998-01-01

    From an experiment with Gammasphere and a 252 Cf spontaneous fission source, a new negative-parity band in 154 Nd and new negative-parity levels in 152 Nd were identified and the yrast bands were extended to 18 + in 154 Nd and 20 + in 152 Nd in a triple gamma coincidence study. These new negative-parity bands are consistent with octupole vibrational mode. There is a constant difference as a function of spin between the J 1 values for the negative-parity band in 152 Nd and J 1 for the similar negative-parity band in 154 Nd, however, their J 2 values are essentially identical. These bands indicate a new kind of identical band. copyright 1998 The American Physical Society

  10. Polymorphisms at Amino Acid Residues 141 and 154 Influence Conformational Variation in Ovine PrP

    Science.gov (United States)

    Yang, Sujeong; Thackray, Alana M.; Hopkins, Lee; Monie, Tom P.; Burke, David F.; Bujdoso, Raymond

    2014-01-01

    Polymorphisms in ovine PrP at amino acid residues 141 and 154 are associated with susceptibility to ovine prion disease: Leu141Arg154 with classical scrapie and Phe141Arg154 and Leu141His154 with atypical scrapie. Classical scrapie is naturally transmissible between sheep, whereas this may not be the case with atypical scrapie. Critical amino acid residues will determine the range or stability of structural changes within the ovine prion protein or its functional interaction with potential cofactors, during conversion of PrPC to PrPSc in these different forms of scrapie disease. Here we computationally identified that regions of ovine PrP, including those near amino acid residues 141 and 154, displayed more conservation than expected based on local structural environment. Molecular dynamics simulations showed these conserved regions of ovine PrP displayed genotypic differences in conformational repertoire and amino acid side-chain interactions. Significantly, Leu141Arg154 PrP adopted an extended beta sheet arrangement in the N-terminal palindromic region more frequently than the Phe141Arg154 and Leu141His154 variants. We supported these computational observations experimentally using circular dichroism spectroscopy and immunobiochemical studies on ovine recombinant PrP. Collectively, our observations show amino acid residues 141 and 154 influence secondary structure and conformational change in ovine PrP that may correlate with different forms of scrapie. PMID:25126555

  11. Hafnium Films and Magnetic Shielding for TIME, A mm-Wavelength Spectrometer Array

    Science.gov (United States)

    Hunacek, J.; Bock, J.; Bradford, C. M.; Butler, V.; Chang, T.-C.; Cheng, Y.-T.; Cooray, A.; Crites, A.; Frez, C.; Hailey-Dunsheath, S.; Hoscheit, B.; Kim, D. W.; Li, C.-T.; Marrone, D.; Moncelsi, L.; Shirokoff, E.; Steinbach, B.; Sun, G.; Trumper, I.; Turner, A.; Uzgil, B.; Weber, A.; Zemcov, M.

    2018-04-01

    TIME is a mm-wavelength grating spectrometer array that will map fluctuations of the 157.7-μm emission line of singly ionized carbon ([CII]) during the epoch of reionization (redshift z ˜ 5-9). Sixty transition-edge sensor (TES) bolometers populate the output arc of each of the 32 spectrometers, for a total of 1920 detectors. Each bolometer consists of gold absorber on a ˜ 3 × 3 mm silicon nitride micro-mesh suspended near the corners by 1 × 1 × 500 μm silicon nitride legs targeting a photon-noise-dominated NEP ˜ 1 × 10^{-17} W/√{Hz} . Hafnium films are explored as a lower-T_c alternative to Ti (500 mK) for TIME TESs, allowing thicker support legs for improved yield. Hf T_c is shown to vary between 250 and 450 mK when varying the resident Ar pressure during deposition. Magnetic shielding designs and simulations are presented for the TIME first-stage SQUIDs. Total axial field suppression is predicted to be 5 × 10^7.

  12. Increased T cell expression of CD154 (CD40-ligand) in multiple sclerosis

    DEFF Research Database (Denmark)

    Jensen, J; Krakauer, M; Sellebjerg, F

    2001-01-01

    CD154 (CD40-ligand, gp39), expressed on activated T cells, is crucial in T cell-dependent immune responses and may be involved in the pathogenesis of multiple sclerosis (MS). We studied cerebro-spinal fluid and peripheral blood T cell expression of CD154 in MS by flow cytometry. Patients with sec......CD154 (CD40-ligand, gp39), expressed on activated T cells, is crucial in T cell-dependent immune responses and may be involved in the pathogenesis of multiple sclerosis (MS). We studied cerebro-spinal fluid and peripheral blood T cell expression of CD154 in MS by flow cytometry. Patients...

  13. 7 CFR 3560.154 - Tenant selection.

    Science.gov (United States)

    2010-01-01

    ... AGRICULTURE DIRECT MULTI-FAMILY HOUSING LOANS AND GRANTS Multi-Family Housing Occupancy § 3560.154 Tenant... documented in the housing project's management plan and Affirmative Fair Housing Marketing Plan. (d... regardless of income. Such applicants, however, will be ranked among themselves by income level, giving...

  14. 18 CFR 154.202 - Filings to initiate a new rate schedule.

    Science.gov (United States)

    2010-04-01

    ... 18 Conservation of Power and Water Resources 1 2010-04-01 2010-04-01 false Filings to initiate a new rate schedule. 154.202 Section 154.202 Conservation of Power and Water Resources FEDERAL ENERGY... contain a notice of the interdependence. (b) If a new service, facility, or rate is specifically...

  15. A spanish mineral of zirconium and hafnium. Separation of the two elements by liquid-liquid extraction, using tributyl phosphate as chelating agent

    International Nuclear Information System (INIS)

    Ruiz Sanchez, F.; Cruz Castillo, F. de la; Fernandez Cellini, R.

    1962-01-01

    The zirconium and Hafnium oxides are obtained from a Spanish mineral of zircon with an average contest of 55% in ZrO 2 -HfO 2 . An alkaline fusion to open the mineral, followed by a purification by crystallization as (Zr O-Hf O)Cl 2 H 2 O or as (Zr-Hf) (SO 4 ) 2 . 4H 2 O, is used. A discussion of the best experimental conditions for opening the mineral and of the purification method is made. (Author) 45 refs

  16. 46 CFR 154.466 - Design criteria.

    Science.gov (United States)

    2010-10-01

    ... GUARD, DEPARTMENT OF HOMELAND SECURITY (CONTINUED) CERTAIN BULK DANGEROUS CARGOES SAFETY STANDARDS FOR... § 154.466 Design criteria. (a) The insulation for a cargo tank without a secondary barrier must be... cargo tank with a secondary barrier must be designed for the secondary barrier at the design temperature...

  17. 46 CFR 154.650 - Cargo tank and process pressure vessel welding.

    Science.gov (United States)

    2010-10-01

    ... 46 Shipping 5 2010-10-01 2010-10-01 false Cargo tank and process pressure vessel welding. 154.650... Equipment Construction § 154.650 Cargo tank and process pressure vessel welding. (a) Cargo tank and process pressure vessel welding must meet Subpart 54.05 and Part 57 of this chapter. (b) Welding consumables used...

  18. Angular correlation and lifetime measurements in /sup 154/Gd

    Energy Technology Data Exchange (ETDEWEB)

    Sharma, A K; Verma, H R; Kaur, R; Sooch, S S; Trehan, P N

    1982-03-01

    Multipole admixtures in 591.80, 692.51, 723.38, 756.84, 873.27, 1004.74, 1274.50, 1494.22 and 1596.65 keV transitions have been measured by investigating nine gamma-gamma angular correlations in /sup 154/Gd. The present study confirms very small Ml admixtures in the transitions from ..beta..- and ..gamma..-vibrational bands to ground state band in /sup 154/Gd which is a transitional nucleus. In addition, lifetime of an excited level at 123.04 keV has been measured to be 1.19 +- 0.03 nsec.

  19. 46 CFR 154.702 - Refrigerated carriage.

    Science.gov (United States)

    2010-10-01

    ... Pressure and Temperature Control § 154.702 Refrigerated carriage. (a) Each refrigeration system must: (1) Have enough capacity to maintain the cargo vapor pressure in each cargo tank served by the system below... the purpose of this section, a “refrigeration unit” includes a compressor and its motors and controls...

  20. George de Hevesy (1885-1966). Discoverer of hafnium, founder of radioanalytical chemistry and X-ray fluorescence analysis and father of nuclear medicine

    International Nuclear Information System (INIS)

    Niese, Siegfried

    2017-01-01

    George de Hevesy known as discoverer of hafnium, founder of radioanalytical chemistry and X-ray fluorescence analysis and father of nuclear medicine has done important research work in inorganic, physical and radioanalytical and physiological chemistry as well as in geochemistry, radiation biology and medicine. When he must flee for political reasons from a country he must change his colleagues, his equipments, and the topic of his work. It is extremely surprising that he could receive important results under such circumstances even at an advanced age. (author)

  1. Multipole mixing ratios in /sup 154/Gd

    Energy Technology Data Exchange (ETDEWEB)

    Chung, Won Mo; Song, Choong Sik; Joo, Koan Sik

    1985-06-01

    We have measured gamma-gamma angular correlations to determine the mixing ratios of several gamma transitions in /sup 154/Gd. The results are compared with those derived from the pairing-plus-quadrupole model and from the interacting boson model.

  2. 46 CFR 154.503 - Piping and piping system components: Protection from movement.

    Science.gov (United States)

    2010-10-01

    ... movement. 154.503 Section 154.503 Shipping COAST GUARD, DEPARTMENT OF HOMELAND SECURITY (CONTINUED) CERTAIN...: Protection from movement. Where thermal movement and movements of the cargo tank and the hull structure may... must be protected from movement by: (a) Offsets; (b) Loops; (c) Bends; (d) Mechanical expansion joints...

  3. Silicon-doped hafnium oxide anti-ferroelectric thin films for energy storage

    Science.gov (United States)

    Ali, Faizan; Liu, Xiaohua; Zhou, Dayu; Yang, Xirui; Xu, Jin; Schenk, Tony; Müller, Johannes; Schroeder, Uwe; Cao, Fei; Dong, Xianlin

    2017-10-01

    Motivated by the development of ultracompact electronic devices as miniaturized energy autonomous systems, great research efforts have been expended in recent years to develop various types of nano-structural energy storage components. The electrostatic capacitors characterized by high power density are competitive; however, their implementation in practical devices is limited by the low intrinsic energy storage density (ESD) of linear dielectrics like Al2O3. In this work, a detailed experimental investigation of energy storage properties is presented for 10 nm thick silicon-doped hafnium oxide anti-ferroelectric thin films. Owing to high field induced polarization and slim double hysteresis, an extremely large ESD value of 61.2 J/cm3 is achieved at 4.5 MV/cm with a high efficiency of ˜65%. In addition, the ESD and the efficiency exhibit robust thermal stability in 210-400 K temperature range and an excellent endurance up to 109 times of charge/discharge cycling at a very high electric field of 4.0 MV/cm. The superior energy storage performance together with mature technology of integration into 3-D arrays suggests great promise for this recently discovered anti-ferroelectric material to replace the currently adopted Al2O3 in fabrication of nano-structural supercapacitors.

  4. Tuning the magnetic properties of pure hafnium by high pressure torsion

    International Nuclear Information System (INIS)

    Cepeda-Jiménez, C.M.; Beltrán, J.I.; Hernando, A.; García, M.A.; Ynduráin, F.; Zhilyaev, A.; Pérez-Prado, M.T.

    2017-01-01

    This work demonstrates that room temperature (RT) ferromagnetism might be triggered in pure hafnium (Hf), a classic paramagnet, by severe plastic deformation (SPD) via high pressure torsion (HPT). The origin of this phenomenon is elucidated by a combined approach including density functional theory (DFT) calculations and transmission electron microscopy (TEM). In particular, it is shown that the elastic lattice distorsions induced in pure Hf as a consequence of grain refinement down to the nanocrystalline regime by HPT lead to the development of a new monoclinic crystalline structure that exhibits a spontaneous magnetization at RT. DFT calculations are utilized to prove that local stretching of the original pure Hf hexagonal close packed (hcp) lattice along specific pyramidal directions, due to the presence of internal stresses in the deformed nanostructure, may give rise to the emergence of the monoclinic phase, which is endowed with a net magnetic moment. An excellent agreement is found between DFT calculations and experimental TEM observations, which provide a first evidence of the presence of the pure Hf monoclinic crystal lattice. This work shows that SPD may constitute a viable, yet widely unexplored, strategy to tune the magnetic properties and, in particular, to induce RT ferromagnetism in bulk non-magnetic metals.

  5. 33 CFR 154.1110 - Purpose and applicability.

    Science.gov (United States)

    2010-07-01

    ... (CONTINUED) POLLUTION FACILITIES TRANSFERRING OIL OR HAZARDOUS MATERIAL IN BULK Additional Response Plan Requirements for a Trans-Alaska Pipeline Authorization Act (TAPAA) Facility Operating in Prince William Sound, Alaska § 154.1110 Purpose and applicability. (a) This subpart establishes oil spill response planning...

  6. Interstellar clouds toward 3C 154 and 3C 353

    International Nuclear Information System (INIS)

    Federman, S.R.; Evans, N.J. II; Willson, R.F.; Falgarone, E.; Combes, F.; Texas Univ., Austin; Tufts Univ., Medford, MA; Meudon, Observatoire, France)

    1987-01-01

    Molecular observations of the interstellar clouds toward the radio sources 3C 154 and 3C 353 were obtained in order to elucidate the physical conditions within the clouds. Maps of (C-12)O emission in the J = 1-0 and J = 2-1 lines were compared with observations of the (C-13)O, CH, and OH molecules. The peak emission in the (C-12)O transitions does not occur in the direction of the continuum sources, and thus, an incomplete picture arises when only one line of sight in the two clouds is analyzed. The cloud toward 3C 154 appears to have a low extinction, but a relatively high CO abundance, suggesting that it is similar to high-latitude clouds and CO-rich diffuse clouds. The cloud toward 3C 353 is considerably denser than that toward 3C 154 and may be more like a dark cloud. 32 references

  7. Characterization of hafnium oxide resistive memory layers deposited on copper by atomic layer deposition

    Energy Technology Data Exchange (ETDEWEB)

    Briggs, B.D.; Bishop, S.M. [SUNY College of Nanoscale Science and Engineering, 255 Fuller Road, Albany, NY 12203 (United States); Leedy, K.D. [Air Force Research Laboratory, 2241 Avionics Circle, Wright Patterson Air Force Base, Dayton, OH 45433 (United States); Cady, N.C., E-mail: ncady@albany.edu [SUNY College of Nanoscale Science and Engineering, 255 Fuller Road, Albany, NY 12203 (United States)

    2014-07-01

    Hafnium oxide-based resistive memory devices have been fabricated on copper bottom electrodes. The HfO{sub x} active layers in these devices were deposited by atomic layer deposition (ALD) at 250 °C with tetrakis(dimethylamido)hafnium(IV) as the metal precursor and an O{sub 2} plasma as the reactant. Depth profiles of the HfO{sub x} by X-ray photoelectron spectroscopy and secondary ion mass spectroscopy revealed a copper concentration on the order of five atomic percent throughout the HfO{sub x} film. In addition to the Cu doped HfO{sub x}, a thin layer (20 nm) of Cu{sub x}O is present at the surface. This surface layer is believed to have formed during the ALD process, and greatly complicates the analysis of the switching mechanism. The resistive memory structures fabricated from the ALD HfO{sub x} exhibited non-polar resistive switching, independent of the top metal electrode (Ni, Pt, Al, Au). Resistive switching current voltage (I–V) curves were analyzed using Schottky emission and ionic hopping models to gain insight into the physical mechanisms underpinning the device behavior. During the forming process it was determined that, at voltages in excess of 2.5 V, an ionic hopping model is in good agreement with the I–V data. The extracted ion hopping distance ∼ 4 Å was within the range of interatomic spacing of HfO{sub 2} during the forming process consistent with ionic motion of Cu{sup 2+} ions. Lastly the on state I–V data was dominated at larger voltages by Schottky emission with an estimated barrier height of ∼ 0.5 eV and a refractive index of 2.59. The consequence of the Schottky emission analysis indicates the on state resistance to be a product of a Pt/Cu{sub 2}O/Cu filament(s)/Cu{sub 2}O/Cu structure. - Highlights: • HfO{sub 2} was grown via atomic layer deposition at 250 and 100 °C on Cu substrates. • A Cu{sub 2}O surface layer and Cu doping were observed in post-deposition of HfO{sub 2}. • Resistive memory devices were fabricated and

  8. Thermodynamic and kinetic studies in the systems alkali chloride-zinconium (or hafnium) tetrachloride: Part I. Vapour pressure measurements over hexachloro compounds and use of vapour pressure data in fractional decomposition

    International Nuclear Information System (INIS)

    Ray, H.S.; Bhat, B.G.; Reddy, G.S.; Biswas, A.K.

    1978-01-01

    A molten tin isoteniscope has been used to measure the vapour pressures over ZrCl 4 , HfCl 4 and the hexachlore zirconates (M 2 ZrCl 6 ) and the hexachloro hafnates (M 2 HfCl 6 ) of four alkali metals (M = Na,K,Rb,Cs). The method of preparation of these compounds and the effect of small amounts of residual alkali chlorides on the their vapour pressure are discussed. The pressure-temperature plots are examined in the light of some theoretical postulates. A scheme for separation of hafnium from zirconoium by multistage fractional decomposition of the hexachlore compounds of any alkali metal is described. The scheme, which is analogous to rectification in liquid-vapour systems, employs a countercurrent flow of Zr(Hf)Cl 4 in a gas stream and a moving bed of alkali chlorides. The separation is based on the difference in the dissociation equilibrium for zirconium and hafnium compounds. Stage calculations for such a scheme and the main conclusions of a computational work are presented. (author)

  9. 46 CFR 154.1170 - Hand hose line: General.

    Science.gov (United States)

    2010-10-01

    ... STANDARDS FOR SELF-PROPELLED VESSELS CARRYING BULK LIQUEFIED GASES Design, Construction and Equipment Firefighting System: Dry Chemical § 154.1170 Hand hose line: General. Each dry chemical hand hose line must: (a...

  10. 20 CFR 655.154 - Additional positive recruitment.

    Science.gov (United States)

    2010-04-01

    ... 20 Employees' Benefits 3 2010-04-01 2010-04-01 false Additional positive recruitment. 655.154... recruitment. (a) Where to conduct additional positive recruitment. The employer must conduct positive recruitment within a multistate region of traditional or expected labor supply where the CO finds that there...

  11. 33 CFR 154.1210 - Purpose and applicability.

    Science.gov (United States)

    2010-07-01

    ... planning requirements for an owner or operator of a facility that handles, stores, or transports animal... (CONTINUED) POLLUTION FACILITIES TRANSFERRING OIL OR HAZARDOUS MATERIAL IN BULK Response Plans for Animal Fats and Vegetable Oils Facilities § 154.1210 Purpose and applicability. (a) The requirements of this...

  12. IL-2 and IL-15 regulate CD154 expression on activated CD4 T cells

    DEFF Research Database (Denmark)

    Skov, S; Bonyhadi, M; Odum, Niels

    2000-01-01

    The cellular and humoral immune system is critically dependent upon CD40-CD154 (CD40 ligand) interactions between CD40 expressed on B cells, macrophages, and dendritic cells, and CD154 expressed primarily on CD4 T cells. Previous studies have shown that CD154 is transiently expressed on CD4 T cells...... after T cell receptor engagement in vitro. However, we found that stimulation of PBLs with maximal CD28 costimulation, using beads coupled to Abs against CD3 and CD28, led to a very prolonged expression of CD154 on CD4 cells (>4 days) that was dependent upon autocrine IL-2 production. Previously...... activated CD4 T cells could respond to IL-2, or the related cytokine IL-15, by de novo CD154 production and expression without requiring an additional signal from CD3 and CD28. These results provide evidence that CD28 costimulation of CD4 T cells, through autocrine IL-2 production, maintains high levels...

  13. 37 CFR 2.154 - Publication in Official Gazette.

    Science.gov (United States)

    2010-07-01

    ..., DEPARTMENT OF COMMERCE RULES OF PRACTICE IN TRADEMARK CASES Publication of Marks Registered Under 1905 Act § 2.154 Publication in Official Gazette. A notice of the claim of benefits under the Act of 1946 and a...

  14. 33 CFR 154.545 - Discharge containment equipment.

    Science.gov (United States)

    2010-07-01

    ... (CONTINUED) POLLUTION FACILITIES TRANSFERRING OIL OR HAZARDOUS MATERIAL IN BULK Equipment Requirements § 154... chapter may be utilized in the planning requirements of subpart F and subpart H of this part. [CGD 75-124... material and equipment to contain any oil or hazardous material discharged on the water from operations at...

  15. 29__154 -158_ _Galadanci_ANALYSIS OF AURORAL

    African Journals Online (AJOL)

    User

    Bayero Journal of Pure and Applied Sciences, 9(2): 154 - 158. Received: April ... monthly averaged data using SPSS version 16.0 with expert modeler, to determine the level, trend ... Auroralsubstorm is a brief disturbance in the Earth's ... The characteristics of a substorm was ... Substorms, on the other hand, take place.

  16. Metallorganic chemical vapor deposition and atomic layer deposition approaches for the growth of hafnium-based thin films from dialkylamide precursors for advanced CMOS gate stack applications

    Science.gov (United States)

    Consiglio, Steven P.

    To continue the rapid progress of the semiconductor industry as described by Moore's Law, the feasibility of new material systems for front end of the line (FEOL) process technologies needs to be investigated, since the currently employed polysilicon/SiO2-based transistor system is reaching its fundamental scaling limits. Revolutionary breakthroughs in complementary-metal-oxide-semiconductor (CMOS) technology were recently announced by Intel Corporation and International Business Machines Corporation (IBM), with both organizations revealing significant progress in the implementation of hafnium-based high-k dielectrics along with metal gates. This announcement was heralded by Gordon Moore as "...the biggest change in transistor technology since the introduction of polysilicon gate MOS transistors in the late 1960s." Accordingly, the study described herein focuses on the growth of Hf-based dielectrics and Hf-based metal gates using chemical vapor-based deposition methods, specifically metallorganic chemical vapor deposition (MOCVD) and atomic layer deposition (ALD). A family of Hf source complexes that has received much attention recently due to their desirable properties for implementation in wafer scale manufacturing is the Hf dialkylamide precursors. These precursors are room temperature liquids and possess sufficient volatility and desirable decomposition characteristics for both MOCVD and ALD processing. Another benefit of using these sources is the existence of chemically compatible Si dialkylamide sources as co-precursors for use in Hf silicate growth. The first part of this study investigates properties of MOCVD-deposited HfO2 and HfSixOy using dimethylamido Hf and Si precursor sources using a customized MOCVD reactor. The second part of this study involves a study of wet and dry surface pre-treatments for ALD growth of HfO2 using tetrakis(ethylmethylamido)hafnium in a wafer scale manufacturing environment. The third part of this study is an investigation of

  17. Recoil Induced Room Temperature Stable Frenkel Pairs in a-Hafnium Upon Thermal Neutron Capture

    Science.gov (United States)

    Butz, Tilman; Das, Satyendra K.; Dey, Chandi C.; Ghoshal, Shamik

    2013-11-01

    Ultrapure hafnium metal (110 ppm zirconium) was neutron activated with a thermal neutron flux of 6:6 · 1012 cm-2s-1 in order to obtain 181Hf for subsequent time differential perturbed angular correlation (TDPAC) experiments using the nuclear probe 181Hf(β-) 181Ta. Apart from the expected nuclear quadrupole interaction (NQI) signal for a hexagonal close-packed (hcp) metal, three further discrete NQIs were observed with a few percent fraction each. The TDPAC spectra were recorded for up to 11 half lives with extreme statistical accuracy. The fitted parameters vary slightly within the temperature range between 248 K and 373 K. The signals corresponding to the three additional sites completely disappear after `annealing' at 453 K for one minute. Based on the symmetry of the additional NQIs and their temperature dependencies, they are tentatively attributed to Frenkel pairs produced by recoil due to the emission of a prompt 5:694 MeV -ray following thermal neutron capture and reported by the nuclear probe in three different positions. These Frenkel pairs are stable up to at least 373 K.

  18. The energy landscape of glassy dynamics on the amorphous hafnium diboride surface

    Science.gov (United States)

    Nguyen, Duc; Mallek, Justin; Cloud, Andrew N.; Abelson, John R.; Girolami, Gregory S.; Lyding, Joseph; Gruebele, Martin

    2014-11-01

    Direct visualization of the dynamics of structural glasses and amorphous solids on the sub-nanometer scale provides rich information unavailable from bulk or conventional single molecule techniques. We study the surface of hafnium diboride, a conductive ultrahigh temperature ceramic material that can be grown in amorphous films. Our scanning tunneling movies have a second-to-hour dynamic range and single-point current measurements extend that to the millisecond-to-minute time scale. On the a-HfB2 glass surface, two-state hopping of 1-2 nm diameter cooperatively rearranging regions or "clusters" occurs from sub-milliseconds to hours. We characterize individual clusters in detail through high-resolution (single cluster vertical displacements, we can reconstruct the local free energy landscape of individual clusters, complete with activation barrier height, a reaction coordinate in nanometers, and the shape of the free energy landscape basins between which hopping occurs. The experimental images are consistent with the compact shape of α-relaxors predicted by random first order transition theory, whereas the rapid hopping rate, even taking less confined motion at the surface into account, is consistent with β-relaxations. We make a proposal of how "mixed" features can show up in surface dynamics of glasses.

  19. About the structure and stability of complex carbonates of thorium (IV), cerium (IV), zirconium (IV), hafnium (IV)

    International Nuclear Information System (INIS)

    Dervin, Jacqueline

    1972-01-01

    This research thesis addressed the study of complex carbonates of cations of metals belonging to the IV A column, i.e. thorium (IV), zirconium (IV), hafnium (IV), and also cerium (IV) and uranium (VI), and more particularly focused on ionic compounds formed in solution, and also on the influence of concentration and nature of cations on stability and nature of the formed solid. The author first presents methods used in this study, discusses their precision and scope of validity. She reports the study of the formation of different complex ions which have been highlighted in solution, and the determination of their formation constants. She reports the preparation and study of the stability domain of solid complexes. The next part reports the use of thermogravimetric analysis, IR spectrometry, and crystallography for the structural study of these compounds

  20. 18 CFR 154.306 - Cash working capital.

    Science.gov (United States)

    2010-04-01

    ... 18 Conservation of Power and Water Resources 1 2010-04-01 2010-04-01 false Cash working capital... Changes § 154.306 Cash working capital. A natural gas company that files a tariff change under this part may not receive a cash working capital adjustment to its rate base unless the company or other...

  1. Characterization of CYP154F1 from Thermobifida fusca YX and Extension of Its Substrate Spectrum by Site-Directed Mutagenesis.

    Science.gov (United States)

    Rühlmann, Ansgar; Groth, Georg; Urlacher, Vlada B

    2018-03-02

    Previous studies on cytochrome P450 monooxygenases (CYP) from family 154 reported their substrate promiscuity and high activity. Hence, herein, the uncharacterized family member CYP154F1 is described. Screening of more than 100 organic compounds revealed that CYP154F1 preferably accepts small linear molecules with a carbon chain length of 8-10 atoms. In contrast to thoroughly characterized CYP154E1, CYP154F1 has a much narrower substrate spectrum and lower activity. A structural alignment of homology models of CYP154F1 and CYP154E1 revealed few differences in the active sites of both family members. By gradual mutagenesis of the CYP154F1 active site towards those of CYP154E1, a key residue accounting for the different activities of both enzymes was identified at position 234. Substitution of T234 for large hydrophobic amino acids led to up to tenfold higher conversion rates of small substrates, such as geraniol. Replacement of T234 by small hydrophobic amino acids, valine or alanine, resulted in mutants with extended substrate spectra. These mutants are able to convert some of the larger substrates of CYP154E1, such as (E)-stilbene and (+)-nootkatone. © 2018 Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim.

  2. Ferroelectric transistors with monolayer molybdenum disulfide and ultra-thin aluminum-doped hafnium oxide

    Science.gov (United States)

    Yap, Wui Chung; Jiang, Hao; Liu, Jialun; Xia, Qiangfei; Zhu, Wenjuan

    2017-07-01

    In this letter, we demonstrate ferroelectric memory devices with monolayer molybdenum disulfide (MoS2) as the channel material and aluminum (Al)-doped hafnium oxide (HfO2) as the ferroelectric gate dielectric. Metal-ferroelectric-metal capacitors with 16 nm thick Al-doped HfO2 are fabricated, and a remnant polarization of 3 μC/cm2 under a program/erase voltage of 5 V is observed. The capability of potential 10 years data retention was estimated using extrapolation of the experimental data. Ferroelectric transistors based on embedded ferroelectric HfO2 and MoS2 grown by chemical vapor deposition are fabricated. Clockwise hysteresis is observed at low program/erase voltages due to slow bulk traps located near the 2D/dielectric interface, while counterclockwise hysteresis is observed at high program/erase voltages due to ferroelectric polarization. In addition, the endurances of the devices are tested, and the effects associated with ferroelectric materials, such as the wake-up effect and polarization fatigue, are observed. Reliable writing/reading in MoS2/Al-doped HfO2 ferroelectric transistors over 2 × 104 cycles is achieved. This research can potentially lead to advances of two-dimensional (2D) materials in low-power logic and memory applications.

  3. 46 CFR 154.1850 - Entering cargo handling spaces.

    Science.gov (United States)

    2010-10-01

    ..., compressors, and compressor motors. (2) Gas-dangerous cargo control spaces. (3) Other spaces containing cargo... cargo handling spaces. (a) The master shall ensure that the ventilation system under § 154.1200 is in... ventilation system, is posted outside of each space under paragraph (a) of this section. (c) The master shall...

  4. 32 CFR 536.154 - Claims involving tortfeasors other than nonappropriated fund employees: NAFI risk management...

    Science.gov (United States)

    2010-07-01

    ... 32 National Defense 3 2010-07-01 2010-07-01 true Claims involving tortfeasors other than nonappropriated fund employees: NAFI risk management program (RIMP) claims. 536.154 Section 536.154 National... nonappropriated fund employees: NAFI risk management program (RIMP) claims. The risk management program (RIMP) is...

  5. Search for superdeformed bands in {sup 154}Dy

    Energy Technology Data Exchange (ETDEWEB)

    Nisius, D.; Janssens, R.V.F.; Khoo, T.L. [and others

    1995-08-01

    The island of superdeformation in the vicinity of the doubly magic {sup 152}Dy yrast superdeformed (SD) band is thought to be well understood in the framework of cranked mean field calculations. In particular, the calculations suggested that in {sup 154}Dy there should be no yrast or near yrast SD minimum in the 40-60 h spin range, where SD bands in this mass region are thought to be {sup 153}Dy nucleus, it is populated. However, with the presence of five SD bands in the neighboring necessary to ascertain if the addition of one single neutron diminishes the importance of shell effects to the extent that superdeformation can no longer be sustained. In an experiment utilizing the increased resolving power of the early implementation phase of Gammasphere, the reaction {sup 122}Sn({sup 36}S,4n) at 165 MeV was employed to populate high spin states in {sup 154}Dy. In a four-day run with 36 detectors, over one billion triple and higher fold coincidence events were recorded. One new SD band was identified and was assigned to {sup 154}Dy. From comparisons with the Im{sup (2)} moments of inertia of the SD bands in {sup 152}Dy and {sup 153}Dy, a configuration based on (514)9/2{sup 2} neutrons coupled to the {sup 152}Dy SD core was proposed. One unexpected and as yet unexplained feature of this new SD band is that the transition energies are almost identical to those of an excited SD band in {sup 153}Dy. It is also worth noting that the feeding of the yrast states is similar to that achieved by the deexcitation from the ensemble of all entry states in the reaction. This observation emphasizes the statistical nature of the decay-out process. A paper reporting these results was accepted for publication.

  6. 42 CFR 483.154 - Nurse aide competency evaluation.

    Science.gov (United States)

    2010-10-01

    ... an individual who is not employed, or does not have an offer to be employed, as a nurse aide becomes... 42 Public Health 5 2010-10-01 2010-10-01 false Nurse aide competency evaluation. 483.154 Section... Requirements That Must Be Met by States and State Agencies: Nurse Aide Training and Competency Evaluation, and...

  7. 32 CFR 154.60 - Evaluating continued security eligibility.

    Science.gov (United States)

    2010-07-01

    ... procedures to enable the appropriate authority to take timely corrective action to protect the interests of... or she may be the target of exploitation by a foreign entity. (ii) Any information of the type referred to in § 154.7 or appendix H to this part. (e) Co-worker responsibility. Co-workers have an equal...

  8. Triploidy--Observations in 154 Diandric Cases.

    Directory of Open Access Journals (Sweden)

    Nanna Brink Scholz

    Full Text Available Hydatidiform moles (HMs are abnormal human pregnancies with vesicular chorionic villi, imposing two clinical challenges; miscarriage and a risk of gestational trophoblastic neoplasia (GTN. The parental type of most HMs are either diandric diploid (PP or diandric triploid (PPM. We consecutively collected 154 triploid or near-triploid samples from conceptuses with vesicular chorionic villi. We used analysis of DNA markers and/or methylation sensitive-MLPA and collected data from registries and patients records. We performed whole genome SNP analysis of one case of twinning (PP+PM.In all 154 triploids or near-triploids we found two different paternal contributions to the genome (P1P2M. The ratios between the sex chromosomal constitutions XXX, XXY, and XYY were 5.7: 6.9: 1.0. No cases of GTN were observed. Our results corroborate that all triploid human conceptuses with vesicular chorionic villi have the parental type P1P2M. The sex chromosomal ratios suggest approximately equal frequencies of meiosis I and meiosis II errors with selection against the XYY conceptuses or a combination of dispermy, non-disjunction in meiosis I and meiosis II and selection against XYY conceptuses. Although single cases of GTN after a triploid HM have been reported, the results of this study combined with data from previous prospective studies estimate the risk of GTN after a triploid mole to 0% (95% CI: 0-1,4%.

  9. 32 CFR 154.42 - Evaluation of personnel security information.

    Science.gov (United States)

    2010-07-01

    ... 32 National Defense 1 2010-07-01 2010-07-01 false Evaluation of personnel security information... SECURITY DEPARTMENT OF DEFENSE PERSONNEL SECURITY PROGRAM REGULATION Adjudication § 154.42 Evaluation of personnel security information. (a) The criteria and adjudicative policy to be used in applying the...

  10. 21 CFR 146.154 - Concentrated orange juice with preservative.

    Science.gov (United States)

    2010-04-01

    ... 21 Food and Drugs 2 2010-04-01 2010-04-01 false Concentrated orange juice with preservative. 146... Canned Fruit Juices and Beverages § 146.154 Concentrated orange juice with preservative. (a) Concentrated orange juice with preservative complies with the requirements for composition and labeling of optional...

  11. Transcriptome Analysis of Mycobacteria-Specific CD4+ T Cells Identified by Activation-Induced Expression of CD154.

    Science.gov (United States)

    Kunnath-Velayudhan, Shajo; Goldberg, Michael F; Saini, Neeraj K; Johndrow, Christopher T; Ng, Tony W; Johnson, Alison J; Xu, Jiayong; Chan, John; Jacobs, William R; Porcelli, Steven A

    2017-10-01

    Analysis of Ag-specific CD4 + T cells in mycobacterial infections at the transcriptome level is informative but technically challenging. Although several methods exist for identifying Ag-specific T cells, including intracellular cytokine staining, cell surface cytokine-capture assays, and staining with peptide:MHC class II multimers, all of these have significant technical constraints that limit their usefulness. Measurement of activation-induced expression of CD154 has been reported to detect live Ag-specific CD4 + T cells, but this approach remains underexplored and, to our knowledge, has not previously been applied in mycobacteria-infected animals. In this article, we show that CD154 expression identifies adoptively transferred or endogenous Ag-specific CD4 + T cells induced by Mycobacterium bovis bacillus Calmette-Guérin vaccination. We confirmed that Ag-specific cytokine production was positively correlated with CD154 expression by CD4 + T cells from bacillus Calmette-Guérin-vaccinated mice and show that high-quality microarrays can be performed from RNA isolated from CD154 + cells purified by cell sorting. Analysis of microarray data demonstrated that the transcriptome of CD4 + CD154 + cells was distinct from that of CD154 - cells and showed major enrichment of transcripts encoding multiple cytokines and pathways of cellular activation. One notable finding was the identification of a previously unrecognized subset of mycobacteria-specific CD4 + T cells that is characterized by the production of IL-3. Our results support the use of CD154 expression as a practical and reliable method to isolate live Ag-specific CD4 + T cells for transcriptomic analysis and potentially for a range of other studies in infected or previously immunized hosts. Copyright © 2017 by The American Association of Immunologists, Inc.

  12. 32 CFR 154.26 - Investigations conducted and clearances granted by other agencies of the Federal government.

    Science.gov (United States)

    2010-07-01

    ... Investigations conducted and clearances granted by other agencies of the Federal government. (a) Whenever a prior... 32 National Defense 1 2010-07-01 2010-07-01 false Investigations conducted and clearances granted by other agencies of the Federal government. 154.26 Section 154.26 National Defense Department of...

  13. IER-297 CED-2: Final Design for Thermal/Epithermal eXperiments with Jemima Plates with Polyethylene and Hafnium

    Energy Technology Data Exchange (ETDEWEB)

    Nelson, A. J. [Lawrence Livermore National Lab. (LLNL), Livermore, CA (United States); Percher, C. M. [Lawrence Livermore National Lab. (LLNL), Livermore, CA (United States); Zywiec, W. J. [Lawrence Livermore National Lab. (LLNL), Livermore, CA (United States); Heinrichs, D. P. [Lawrence Livermore National Lab. (LLNL), Livermore, CA (United States)

    2018-01-11

    This report presents the final design (CED-2) for IER-297, and focuses on 15 critical configurations using highly enriched uranium (HEU) Jemima plates moderated by polyethylene with and without hafnium diluent. The goal of the U.S. Nuclear Criticality Safety Program’s Thermal/Epithermal eXperiments (TEX) is to design and conduct new critical experiments to address high priority nuclear data needs from the nuclear criticality safety and nuclear data communities, with special emphasis on intermediate energy (0.625 eV – 100 keV) assemblies that can be easily modified to include various high priority diluent materials. The TEX (IER 184) CED-1 Report [1], completed in 2012, demonstrated the feasibility of meeting the TEX goals with two existing NCSP fissile assets, plutonium Zero Power Physics Reactor (ZPPR) plates and highly enriched uranium (HEU) Jemima plates. The first set of TEX experiments will focus on using the plutonium ZPPR plates with polyethylene moderator and tantalum diluents.

  14. Modification of erbium photoluminescence excitation spectra for the emission wavelength 1.54 μm in mesoscopic structures

    International Nuclear Information System (INIS)

    Gaponenko, N.V.; Unuchak, D.M.; Mudryi, A.V.; Malyarevich, G.K.; Gusev, O.B.; Stepikhova, M.V.; Krasilnikova, L.V.; Stupak, A.P.; Kleshcheva, S.M.; Samoilovich, M.I.; Tsvetkov, M.Yu.

    2006-01-01

    Photoluminescence excitation (PLE) spectra for the emission wavelength 1.54 μm were studied for erbium-doped xerogels embedded in artificial opals and porous anodic alumina films. Opals were chosen with photonic stop-band in green spectral range, where excitation of 1.54 μm occurs most efficiently. In comparison to the structure erbium-doped titania xerogel/porous anodic alumina/silicon the photoluminescence excitation spectra for 1.54 μm emission wavelength significantly changes for the same xerogels embedded in artificial opals. Enhancement of erbium-related 1.54 μm emission was observed from the structure Fe 2 O 3 xerogel/porous anodic alumina fabricated on silicon, having some incompletely anodized aluminium, under excitation with either the lasing source at 532 nm or xenon lamp. Evident difference in PLE spectra for erbium doped TiO 2 and Fe 2 O 3 xerogels in porous anodic alumina is observed

  15. The Interaction of CD154 with the α5β1 Integrin Inhibits Fas-Induced T Cell Death.

    Science.gov (United States)

    Bachsais, Meriem; Naddaf, Nadim; Yacoub, Daniel; Salti, Suzanne; Alaaeddine, Nada; Aoudjit, Fawzi; Hassan, Ghada S; Mourad, Walid

    2016-01-01

    CD154, a critical regulator of the immune response, is usually associated with chronic inflammatory, autoimmune diseases as well as malignant disorders. In addition to its classical receptor CD40, CD154 is capable of binding other receptors, members of the integrin family, the αIIbβ3, αMβ2 and α5β1. Given the role attributed to integrins and particularly the β1 integrins in inhibiting apoptotic events in normal as well as malignant T cells, we were highly interested in investigating the role of the CD154/α5β1 interaction in promoting survival of malignant T cells contributing as such to tumor development and/or propagation. To support our hypothesis, we first show that soluble CD154 binds to the T-cell acute lymphoblastic leukemia cell line, Jurkat E6.1 in a α5β1-dependent manner. Binding of soluble CD154 to α5β1 integrin of Jurkat cells leads to the activation of key survival proteins, including the p38 and ERK1/2 mitogen-activated protein kinases (MAPKs), phosphoinositide 3 kinase (PI-3K), and Akt. Interestingly, soluble CD154 significantly inhibits Fas-mediated apoptosis in T cell leukemia-lymphoma cell lines, Jurkat E6.1 and HUT78 cells, an important hallmark of T cell survival during malignancy progression. These anti-apoptotic effects were mainly mediated by the activation of the PI-3K/Akt pathway but also involved the p38 and the ERK1/2 MAPKs cascades. Our data also demonstrated that the CD154-triggered inhibition of the Fas-mediated cell death response was dependent on a suppression of caspase-8 cleavage, but independent of de novo protein synthesis or alterations in Fas expression on cell surface. Together, our results highlight the impact of the CD154/α5β1 interaction in T cell function/survival and identify novel targets for the treatment of malignant disorders, particularly of T cell origin.

  16. The Interaction of CD154 with the α5β1 Integrin Inhibits Fas-Induced T Cell Death.

    Directory of Open Access Journals (Sweden)

    Meriem Bachsais

    Full Text Available CD154, a critical regulator of the immune response, is usually associated with chronic inflammatory, autoimmune diseases as well as malignant disorders. In addition to its classical receptor CD40, CD154 is capable of binding other receptors, members of the integrin family, the αIIbβ3, αMβ2 and α5β1. Given the role attributed to integrins and particularly the β1 integrins in inhibiting apoptotic events in normal as well as malignant T cells, we were highly interested in investigating the role of the CD154/α5β1 interaction in promoting survival of malignant T cells contributing as such to tumor development and/or propagation. To support our hypothesis, we first show that soluble CD154 binds to the T-cell acute lymphoblastic leukemia cell line, Jurkat E6.1 in a α5β1-dependent manner. Binding of soluble CD154 to α5β1 integrin of Jurkat cells leads to the activation of key survival proteins, including the p38 and ERK1/2 mitogen-activated protein kinases (MAPKs, phosphoinositide 3 kinase (PI-3K, and Akt. Interestingly, soluble CD154 significantly inhibits Fas-mediated apoptosis in T cell leukemia-lymphoma cell lines, Jurkat E6.1 and HUT78 cells, an important hallmark of T cell survival during malignancy progression. These anti-apoptotic effects were mainly mediated by the activation of the PI-3K/Akt pathway but also involved the p38 and the ERK1/2 MAPKs cascades. Our data also demonstrated that the CD154-triggered inhibition of the Fas-mediated cell death response was dependent on a suppression of caspase-8 cleavage, but independent of de novo protein synthesis or alterations in Fas expression on cell surface. Together, our results highlight the impact of the CD154/α5β1 interaction in T cell function/survival and identify novel targets for the treatment of malignant disorders, particularly of T cell origin.

  17. 10 CFR 455.154 - Discretionary review by the Assistant Secretary.

    Science.gov (United States)

    2010-01-01

    ... Section 455.154 Energy DEPARTMENT OF ENERGY ENERGY CONSERVATION GRANT PROGRAMS FOR SCHOOLS AND HOSPITALS AND BUILDINGS OWNED BY UNITS OF LOCAL GOVERNMENT AND PUBLIC CARE INSTITUTIONS Administrative Review... statement of reasons, for discretionary review by the Assistant Secretary. If administrative review is...

  18. Oxygen-saving effect of a new cardiotonic agent, MCI-154, in diseased human hearts.

    Science.gov (United States)

    Mori, M; Takeuchi, M; Takaoka, H; Hata, K; Hayashi, Y; Yamakawa, H; Yokoyama, M

    1997-03-01

    The aim of this study was to examine the left ventricular mechanoenergetic effects of a novel Ca2+ sensitizing agent, MCI-154, on diseased human hearts compared with dobutamine. Unlike conventional cardiotonic agents, a Ca2+ sensitizer that could produce a positive inotropic action by altering the responsiveness of myofilament to Ca2+ could generate force with smaller amounts of Ca2+; thus, it may potentially save energy expenditure. The left ventricular pressure-volume relation and myocardial oxygen consumption per beat (Vo2) were measured by a conductance (volume) catheter and a Webster catheter. Left ventricular contractility (Emax), systolic pressure-volume area (PVA [index of left ventricular total mechanical energy]) and Vo2 were assessed before and after infusion of MCI-154 or dobut-amine. The PVA-independent Vo2 (Vo2 mainly for excitation-contraction coupling) was assessed as the Vo2 at zero PVA. Both agents increased Emax comparably (dobutamine: from 3.55 +/- 1.10 [mean +/- SD] to 5.04 +/- 1.16 mm Hg/ml per m2, p delta PVA-independent Vo2/delta Emax) was less with MCI-154 than with dobutamine (0.14 +/- 0.18 vs. 1.10 +/- 0.80 J/mm Hg per ml per m2, p action mediated by MCI-154 could provide an energetic advantage over the conventional cardiotonic action with currently used inotropic agents.

  19. Improved DC performance of AlGaN/GaN high electron mobility transistors using hafnium oxide for surface passivation

    International Nuclear Information System (INIS)

    Liu, Chang; Chor, Eng Fong; Tan, Leng Seow

    2007-01-01

    Improved DC performance of AlGaN/GaN high electron mobility transistors (HEMTs) have been demonstrated using reactive-sputtered hafnium oxide (HfO 2 ) thin film as the surface passivation layer. Hall data indicate a significant increase in the product of sheet carrier concentration (n s ) and electron mobility (μ n ) in the HfO 2 -passivated HEMTs, compared to the unpassivated HEMTs. This improvement in electron carrier characteristics gives rise to a 22% higher I Dmax and an 18% higher g mmax in HEMTs with HfO 2 passivation relative to the unpassivated devices. On the other hand, I gleak of the HEMTs decreases by nearly one order of magnitude when HfO 2 passivation is applied. In addition, drain current is measured in the subthreshold regime. Compared to the unpassivated HEMTs, HfO 2 -passivated HEMTs exhibit a much smaller off-state I D , indicating better turn-off characteristics

  20. Protective coatings of hafnium dioxide by atomic layer deposition for microelectromechanical systems applications

    Energy Technology Data Exchange (ETDEWEB)

    Berdova, Maria, E-mail: maria.berdova@aalto.fi [Aalto University, Department of Materials Science and Engineering, 02150, Espoo (Finland); Wiemer, Claudia; Lamperti, Alessio; Tallarida, Grazia; Cianci, Elena [Laboratorio MDM, IMM CNR, Via C. Olivetti 2, 20864, Agrate Brianza, MB (Italy); Lamagna, Luca; Losa, Stefano; Rossini, Silvia; Somaschini, Roberto; Gioveni, Salvatore [STMicroelectronics, Via C. Olivetti 2, 20864, Agrate Brianza, MB (Italy); Fanciulli, Marco [Laboratorio MDM, IMM CNR, Via C. Olivetti 2, 20864, Agrate Brianza, MB (Italy); Università degli studi di Milano Bicocca, Dipartimento di Scienza dei Materiali, 20126, Milano (Italy); Franssila, Sami, E-mail: sami.franssila@aalto.fi [Aalto University, Department of Materials Science and Engineering, 02150, Espoo (Finland)

    2016-04-15

    Graphical abstract: - Highlights: • Atomic layer deposition of HfO{sub 2} from (CpMe){sub 2}Hf(OMe)Me or Hf(NMeEt){sub 4} and ozone for potential applications in microelectromechanical systems. • ALD HfO{sub 2} protects aluminum substrates from degradation in moist environment and at the same time retains good reflectance properties of the underlying material. • The resistance of hafnium dioxide to moist environment is independent of chosen precursors. - Abstract: This work presents the investigation of HfO{sub 2} deposited by atomic layer deposition (ALD) from either HfD-CO4 or TEMAHf and ozone for microelectromechanical systems (MEMS) applications, in particular, for environmental protection of aluminum micromirrors. This work shows that HfO{sub 2} films successfully protect aluminum in moist environment and at the same time retain good reflectance properties of underlying material. In our experimental work, the chemical composition, crystal structure, electronic density and roughness of HfO{sub 2} films remained the same after one week of humidity treatment (relative humidity of 85%, 85 °C). The reflectance properties underwent only minor changes. The observed shift in reflectance was only from 80–90% to 76–85% in 400–800 nm spectral range when coated with ALD HfO{sub 2} films grown with Hf(NMeEt){sub 4} and no shift (remained in the range of 68–83%) for films grown from (CpMe){sub 2}Hf(OMe)Me.

  1. Hydroxychloroquine inhibits CD154 expression in CD4+ T lymphocytes of systemic lupus erythematosus through NFAT, but not STAT5, signaling.

    Science.gov (United States)

    Wu, Shu-Fen; Chang, Chia-Bin; Hsu, Jui-Mei; Lu, Ming-Chi; Lai, Ning-Sheng; Li, Chin; Tung, Chien-Hsueh

    2017-08-09

    Overexpression of membranous CD154 in T lymphocytes has been found previously in systemic lupus erythematosus (SLE). Because hydroxychloroquine (HCQ) has been used frequently in the treatment of lupus, we sought to identify the effects of HCQ on CD154 and a possibly regulatory mechanism. CD4 + T cells were isolated from the blood of lupus patients. After stimulation with ionomycin or IL-15 and various concentrations of HCQ, expression of membranous CD154 and NFAT and STAT5 signaling were assessed. HCQ treatment had significant dose-dependent suppressive effects on membranous CD154 expression in ionomycin-activated T cells from lupus patients. Furthermore, HCQ inhibited intracellular sustained calcium storage release, and attenuated the nuclear translocation of NFATc2 and the expression of NFATc1. However, CD154 expressed through IL-15-mediated STAT5 signaling was not inhibited by HCQ treatment. HCQ inhibited NFAT signaling in activated T cells and blocked the expression of membranous CD154, but not STAT5 signaling. These findings provide a mechanistic insight into SLE in HCQ treatment.

  2. 30 CFR 210.154 - What documents or other information must I submit for Federal oil valuation purposes?

    Science.gov (United States)

    2010-07-01

    ... express mail addressed to Minerals Management Service, P.O. Box 25165, MS 392B2, Denver, Colorado 80217... 30 Mineral Resources 2 2010-07-01 2010-07-01 false What documents or other information must I submit for Federal oil valuation purposes? 210.154 Section 210.154 Mineral Resources MINERALS MANAGEMENT...

  3. 38 CFR 17.154 - Dog-guides and equipment for blind.

    Science.gov (United States)

    2010-07-01

    ... 38 Pensions, Bonuses, and Veterans' Relief 1 2010-07-01 2010-07-01 false Dog-guides and equipment... AFFAIRS MEDICAL Prosthetic, Sensory, and Rehabilitative Aids § 17.154 Dog-guides and equipment for blind... disability may be furnished a trained dog-guide. In addition, they may be furnished necessary travel expense...

  4. Efficient UV-emitting X-ray phosphors: octahedral Zr(PO4)6 luminescence centers in potassium hafnium-zirconium phosphates K2Hf1-xZrx(PO4)2 and KHf2(1-x)Zr2x(PO4)3

    International Nuclear Information System (INIS)

    Torardi, C.C.; Miao, C.R.; Li, J.

    2003-01-01

    Potassium hafnium-zirconium phosphates, K 2 Hf 1-x Zr x (PO 4 ) 2 and KHf 2(1-x) Zr 2x (PO 4 ) 3 , are broad-band UV-emitting phosphors. At room temperature, they have emission peak maxima at approximately 322 and 305 nm, respectively, under 30 kV peak molybdenum X-ray excitation. Both phosphors demonstrate luminescence efficiencies that make them up to ∼60% as bright as commercially available CaWO 4 Hi-Plus. The solid-state and flux synthesis conditions, and X-ray excited UV luminescence of these two phosphors are discussed. Even though the two compounds have different atomic structures, they contain zirconium in the same active luminescence environment as that found in highly efficient UV-emitting BaHf 1-x Zr x (PO 4 ) 2 . All the three materials have hafnium and zirconium in octahedral coordination via oxygen-atom corner sharing with six separate PO 4 tetrahedra. This octahedral Zr(PO 4 ) 6 moiety appears to be an important structural element for efficient X-ray excited luminescence, as are the edge-sharing octahedral TaO 6 chains for tantalate emission

  5. Novel adaptive distance relay algorithm considering the operation of 154 kV SFCL in Korean power transmission system

    International Nuclear Information System (INIS)

    Lee, S.; Lee, J.; Song, S.; Yoon, J.; Lee, B.

    2015-01-01

    Highlights: • This paper presents an outline of the new project of the 154 kV SFCL in Korea. • And then we review some protection problems for the application of 154 kV SFCLs. • This paper proposes a new adaptive protection algorithm for 154 kV SFCLs. • The developed algorithm is tested in a simple distance relay system. - Abstract: In general, SFCLs can have a negative impact on the protective coordination in power transmission system because of the variable impedance of SFCLs. It is very important to solve the protection problems of the power system for the successful application of SFCLs to real power transmission system. This paper reviews some protection problems which can be caused by the application of 154 kV SFCLs to power transmission systems in South Korea. And then we propose an adaptive protection algorithm to solve the problems. The adaptive protection algorithm uses the real time information of the SFCL system operation.

  6. GD 154: White dwarf with multi- and monoperiodic pulsation

    Directory of Open Access Journals (Sweden)

    Bognár Zs.

    2013-03-01

    Full Text Available We present the white dwarf GD 154 as an example where either monoperiodic or multiperiodic pulsation were found at different epochs. The mono-multi-monoperiodic stage seems to alternate. Many questions have been raised. Is this behaviour connected to the evolution of DAV stars? How often does it happen? Is there any regularity in this change of the pulsational behaviour or is it irregular?

  7. 46 CFR Appendix B to Part 154 - Stress Analyses Definitions

    Science.gov (United States)

    2010-10-01

    ... 46 Shipping 5 2010-10-01 2010-10-01 false Stress Analyses Definitions B Appendix B to Part 154...—Stress Analyses Definitions The following are the standard definitions of stresses for the analysis of an independent tank type B: Normal stress means the component of stress normal to the plane of reference...

  8. Gamma-gamma directional correlations and coincidence studies in 154Gd

    International Nuclear Information System (INIS)

    Gupta, J.B.; Gupta, S.L.; Hamilton, J.H.; Ramayya, A.V.; Delhi Univ.

    1977-01-01

    The intensities, placements and E2/M1 mixing ratios of transitions in the decay of 154 Eu have been carefully studied to provide accurate data for microscopic calculations. Coincidence relationships in thhe decay of 154 Eu have been studied extensively with a multiparameter γ-γ coincidence system with two large volume Ge(Li) detectors. Spectra in coincidence with twenty energy gates were analyzed. Twenty-nine new coincidence relationships were established and confirmed most, but not all, of several levels previously assigned by energy fits only. From an analysis of coincidence spectra and singles spectra with a 18% efficiency Ge(Li) detector new information on the gamma-ray intensities were obtained. Precise values of the E2/M1 mixing ratios of transitions from the gamma- and beta-vibrational bands to the g.s. band have been determined from γ-γ directional correlation measurements with a NaI(Tl)-Ge(Li) detector coincidence system. Mixing ratios were obtained for a number of other transitions including those from KPI = 0 - and 2+ bands from direct and skipped cascade correlations. (orig.) [de

  9. 29 CFR 784.154 - Relationship to other operations as affecting exemption.

    Science.gov (United States)

    2010-07-01

    ... Exemptions Provisions Relating to Fishing and Aquatic Products Marketing, Storing, Packing for Shipment, and Distributing § 784.154 Relationship to other operations as affecting exemption. Employment in marketing... 29 Labor 3 2010-07-01 2010-07-01 false Relationship to other operations as affecting exemption...

  10. Evaluation of n + 144,148,154Sm reaction data

    International Nuclear Information System (INIS)

    Ming Jianchuan; Zhuang Youxiang

    2000-01-01

    The neutron cross section data were evaluated for n + 144,148,154 Sm reaction in the energy range 10 -5 eV to 20 MeV. Spline function was used in the experimental data fit calculation. The corresponding JENDL-3 data are accepted in the energy range of 0.025 to 100 Kev. The comparisons among calculation data and experimental data, JENDL-3 data ENDF/B-6 data are presented

  11. 154.pdf | 25jan2011 | currsci | Indian Academy of Sciences

    Indian Academy of Sciences (India)

    Home; currsci; 25jan2011; 154.pdf. 404! error. The page your are looking for can not be found! Please check the link or use the navigation bar at the top. YouTube · Twitter · Facebook · Blog. Academy News. IAS Logo. Ethical Guidelines and Procedures document. Posted on 17 January 2017. A revised version of the ...

  12. Electromigration of /sup 153,154/Eu on CAM

    Energy Technology Data Exchange (ETDEWEB)

    Xianyun, He; Peiji, Chong

    1986-05-01

    The electromigration of /sup 153,154/Eu was studied with cellulose acetate membrane (CAM) as the supporting material. The factors influencing the migration were investigated, including electric field intensity, concentration and pH of the electrolyte, ionic strength and temperature. The stability constant of EuR/sup 2+/ complex and its electromobility were determined to be 1549 and 1.2 x 10/sup -7/ cm/sup 2//s. V respectively under the following conditions: (alpha-HIBA) = 0.4 M, mu = 0.01, Voltage = 1000 V.

  13. Recovery of metal chlorides from their complexes by molten salt displacement

    International Nuclear Information System (INIS)

    McLaughlin, D.F.; Stoltz, R.A.

    1989-01-01

    This patent describes a process for recovering zirconium or hafnium chloride from a complex of zirconium or hafnium tetrachloride and phosphorus oxychloride. The process comprising: introducing liquid complex of zirconium or hafnium tetrachloride and phosphorus oxychloride into an upper portion of a feed column containing zirconium or hafnium tetrachloride vapor and phosphorus oxychloride vapor. The liquid complex absorbing zirconium or hafnium tetrachloride vapor and producing a bottoms liquid and also producing a phosphorus oxychloride vapor stripped of zirconium or hafnium tetrachloride; introducing the bottoms liquid into a molten salt containing displacement reactor, the reactor containing molten salt comprising at least 30 mole percent lithium chloride and at least 30 mole percent of at least one other alkali metal chloride, the reactor being heated to 30-450 0 C to displace phosphorus oxychloride from the complex and product zirconium or hafnium tetrachloride vapor and phosphorus oxychloride vapor and zirconium or hafnium tetrachloride-containing molten salt; introducing the zirconium or hafnium tetrachloride vapor and the phosphorus oxychloride vapor into the feed column below the point of introduction of the liquid stream; introducing the zirconium or hafnium tetrachloride containing-molten salt into a recovery vessel where zirconium or hafnium tetrachloride is removed from the molten salt to produce zirconium or hafnium tetrachloride product and zirconium or hafnium chloride-depleted molten salt; and recycling the zirconium or hafnium tetachloride-depleted molten salt to the displacement reactor

  14. Use of almond endocarp shell in sorption of radioactive 152+154Europium from waste solutions

    International Nuclear Information System (INIS)

    Dakroury, G.A.; Khalil, T.; Abou El-Nour, F.H.

    2007-01-01

    In an attempt to remove radioactive ( 152 + 154 )Eu from waste solutions, the present study was tried to explore the possibility of using a natural by-product. Almond endocarp (AEC) shell produced from Sinai (El-Arish area) was selected as agricultural by-product in treatment of waste solutions containing ( 152 + 154 )Eu through a batch technique. The different physico-chemical characteristics of AEC such as specific surface area, total pore volume, average pore diameter, apparent density, porosity and pore size distribution were calculated. The adsorption process was described by a Freundlich type isotherm. The uptake percent of the metal ion was determined for the sorbent material as a function of contact time, pH-value, mass of the sorbent material, metal ion concentration and the effect of competing ions on the sorption process. The obtained data were analyzed and showed that almond endocarp shell powder can be considered as an efficient natural material to be used for sorption of radioactive ( 152 + 154 )Eu from their radioactive waste solutions

  15. 17 CFR 1.54 - Contract market rules submitted to and approved or not disapproved by the Secretary of Agriculture.

    Science.gov (United States)

    2010-04-01

    ... submitted to and approved or not disapproved by the Secretary of Agriculture. 1.54 Section 1.54 Commodity... Secretary of Agriculture. Notwithstanding any provision of these rules, any bylaw, rule, regulation, or resolution of a contract market that was submitted to the Secretary of Agriculture pursuant or § 1.38(a) or...

  16. Regiospecific synthesis of 15-(4-[123I]iodophenyl)pentadecanoic acid-IPPA via methyl 15-(4-trimethylstannylphenyl)pentadecanoate

    International Nuclear Information System (INIS)

    Culbert, P.A.; Jianming Lu; Adam, M.J.

    1997-01-01

    The synthesis of methyl 15-(4-trimethylstannylphenyl)pentadecanoate (p-SnPPA), a precursor for the regiospecific production of 15-(4-[ 123 I]-iodophenyl)pentadecanoic acid, is described. The stannylated precursor is synthesized in six steps from 4-bromophenylacetylene in an overall yield of 16%. p-SnPPA reacts with N.C.A. [ 123 I]NaI in the presence of peracetic acid to yield IPPA in 62% radiochemical yield following hydrolysis. (author)

  17. Growth of HfO{sub x} thin films by reactive molecular beam epitaxy

    Energy Technology Data Exchange (ETDEWEB)

    Hildebrandt, Erwin; Kurian, Jose; Alff, Lambert [Institut fuer Materialwissenschaft, TU Darmstadt (Germany)

    2008-07-01

    Thin films of hafnium oxide were grown on single crystal r-cut and c-cut sapphire by reactive molecular beam epitaxy. The conditions for the growth of single oriented hafnium oxide thin films have been established. Hafnium oxide thin films were characterized by X-ray diffraction and optical absorption measurements. It was found that hafnium oxide thin films grown on r-cut sapphire were (00l) oriented whereas, on c-cut sapphire, hafnium oxide films showed different orientations depending on the growth temperature and oxidation conditions. The hafnium oxide films grown at higher temperature and under strong oxidation conditions yielded (001) oriented films on c-cut sapphire whereas slightly weaker oxidation condition leads to (111) oriented hafnium oxide films. The bandgap deducted from optical absorption measurement carried out on hafnium oxide films grown under optimized conditions agreed well with the values reported in literature. A range of oxygen deficient thin films of hafnium oxide were also grown on single crystal sapphire substrates in order to investigate the effect of oxygen vacancies on dielectric properties of hafnium oxide. The oxygen deficient thin films of hafnium oxide show a decrease in bandgap with increase in oxygen deficiency.

  18. Gamma--gamma directional correlations and coincidence studies in /sup 154/Gd

    Energy Technology Data Exchange (ETDEWEB)

    Gupta, J B; Gupta, S L; Hamilton, J H; Ramayya, A V [Vanderbilt Univ., Nashville, Tenn. (USA). Dept. of Physics; Delhi Univ. (India). Ramjas Coll.)

    1977-06-01

    The intensities, placements and E2/M1 mixing ratios of transitions in the decay of /sup 154/Eu have been carefully studied to provide accurate data for microscopic calculations. Coincidence relationships in thhe decay of /sup 154/Eu have been studied extensively with a multiparameter ..gamma..-..gamma.. coincidence system with two large volume Ge(Li) detectors. Spectra in coincidence with twenty energy gates were analyzed. Twenty-nine new coincidence relationships were established and confirmed most, but not all, of several levels previously assigned by energy fits only. From an analysis of coincidence spectra and singles spectra with a 18% efficiency Ge(Li) detector new information on the gamma-ray intensities were obtained. Precise values of the E2/M1 mixing ratios of transitions from the gamma- and beta-vibrational bands to the g.s. band have been determined from ..gamma..-..gamma.. directional correlation measurements with a NaI(Tl)-Ge(Li) detector coincidence system. Mixing ratios were obtained for a number of other transitions including those from KPI = 0/sup -/ and 2+ bands from direct and skipped cascade correlations.

  19. Evaluation and Enhancement of the Oxygen Reduction Reaction Activity on Hafnium Oxide Nanoparticles Assisted by L(+)-lysine

    International Nuclear Information System (INIS)

    Chisaka, Mitsuharu; Itagaki, Noriaki

    2016-01-01

    Evaluation of the oxygen reduction reaction (ORR) on oxide compounds is difficult owing to the insulating nature of oxides. In this study, various amounts of L(+)-lysine were added to the precursor dispersion for the hydrothermal synthesis of hafnium oxide nanoparticles on reduced graphene oxide sheets (HfO_x–rGO) to coat the HfO_x catalysts with layers of carbon, thereby increasing the conductivity and number of active sites. When the mass ratio of L(+)-lysine to GO, R, was above 26, carbon layers were formed and the amount monotonically increased with increasing R, as noted by cyclic voltammogrametry. X-ray photoelectron spectroscopy and rotating disk electrode analyses revealed that pyrolysis produced ORR-active oxygen defects, whose formation was proposed to involve carbothermal reduction. When 53 ≤ R ≤ 210, HfO_x–rGO contained a similar amount of oxygen defects and ORR activity, as represented by an onset potential of 0.9 V versus the reversible hydrogen electrode in 0.1 mol dm"−"3 H_2SO_4. However, the number of active sites depended on R due to the amount of L(+)-lysine-derived carbon layers that increased both the number of active sites and resistivity towards oxygen diffusion.

  20. Mechanistic Studies of Hafnium-Pyridyl Amido-Catalyzed 1-Octene Polymerization and Chain Transfer Using Quench-Labeling Methods.

    Science.gov (United States)

    Cueny, Eric S; Johnson, Heather C; Anding, Bernie J; Landis, Clark R

    2017-08-30

    Chromophore quench-labeling applied to 1-octene polymerization as catalyzed by hafnium-pyridyl amido precursors enables quantification of the amount of active catalyst and observation of the molecular weight distribution (MWD) of Hf-bound polymers via UV-GPC analysis. Comparison of the UV-detected MWD with the MWD of the "bulk" (all polymers, from RI-GPC analysis) provides important mechanistic information. The time evolution of the dual-detection GPC data, concentration of active catalyst, and monomer consumption suggests optimal activation conditions for the Hf pre-catalyst in the presence of the activator [Ph 3 C][B(C 6 F 5 ) 4 ]. The chromophore quench-labeling agents do not react with the chain-transfer agent ZnEt 2 under the reaction conditions. Thus, Hf-bound polymeryls are selectively labeled in the presence of zinc-polymeryls. Quench-labeling studies in the presence of ZnEt 2 reveal that ZnEt 2 does not influence the rate of propagation at the Hf center, and chain transfer of Hf-bound polymers to ZnEt 2 is fast and quasi-irreversible. The quench-label techniques represent a means to study commercial polymerization catalysts that operate with high efficiency at low catalyst concentrations without the need for specialized equipment.

  1. 46 CFR 154.706 - Cargo boil-off as fuel: Fuel lines.

    Science.gov (United States)

    2010-10-01

    ... exhaust-ventilated pipe or duct, having a rate of air change of at least 30 changes per hour. The pressure in the space between the inner pipe and outer pipe or duct must be maintained at less than... ventilation system must meet § 154.1205. (b) Each double wall pipe or vent duct must terminate in the...

  2. Characteristics of laser produced plasmas of hafnium and tantalum in the 1-7 nm region

    Science.gov (United States)

    Li, Bowen; Otsuka, Takamitsu; Sokell, Emma; Dunne, Padraig; O'Sullivan, Gerry; Hara, Hiroyuki; Arai, Goki; Tamura, Toshiki; Ono, Yuichi; Dinh, Thanh-Hung; Higashiguchi, Takeshi

    2017-11-01

    Soft X-ray (SXR) spectra from hafnium and tantalum laser produced plasmas were recorded in the 1-7 nm region using two Nd:YAG lasers with pulse lengths of 170 ps and 10 ns, respectively, operating at a range of power densities. The maximum focused peak power density was 2. 3 × 1014 W cm-2 for 170 ps pulses and 1. 8 × 1012 W cm-2 for 10 ns pulses, respectively. Two intense quasicontinuous intensity bands resulting from n = 4 - n = 4 and n = 4 - n = 5 unresolved transition arrays (UTAs) dominate both sets of experimental spectra. Comparison with calculations performed with the Cowan suite of atomic structure codes as well as consideration of previous experimental and theoretical results aided identification of the most prominent features in the spectra. For the 10 ns spectrum, the highest ion stage that could be identified from the n = 4 - n = 5 arrays were lower than silver-like Hf25+ and Ta26+ (which has a 4 d 104 f ground configuration) indicating that the plasma temperature attained was too low to produce ions with an outermost 4 d subshell, while for the 170 ps plasmas the presence of significantly higher stages was deduced and lines due to 4 d-5 p transitions were clearly evident. Furthermore, we show an enhancement of emission from tantalum using dual laser irradiation, and the effect of pre-pulse durations and delay times between two pulses are demonstrated.

  3. 40 CFR 154.5 - Burden of persuasion in determinations under this part.

    Science.gov (United States)

    2010-07-01

    ... 40 Protection of Environment 23 2010-07-01 2010-07-01 false Burden of persuasion in determinations... (CONTINUED) PESTICIDE PROGRAMS SPECIAL REVIEW PROCEDURES General Provisions § 154.5 Burden of persuasion in... principle that the burden of persuasion that a pesticide product is entitled to registration or continued...

  4. 33 CFR Appendix A to Part 154 - Guidelines for Detonation Flame Arresters

    Science.gov (United States)

    2010-07-01

    ... SECURITY (CONTINUED) POLLUTION FACILITIES TRANSFERRING OIL OR HAZARDOUS MATERIAL IN BULK Pt. 154, App. A... constructed to minimize the effect of fouling under normal operating conditions. 8.11Detonation flame... diameters long with a plastic bag over the free end. (Alternate end of pipe closures are also acceptable...

  5. X-ray tube target

    International Nuclear Information System (INIS)

    Weber, R.G.

    1980-01-01

    A target with an improved heat emissive surface for use in a rotating anode type x-ray tube is described. The target consists of a body having a first surface portion made of x-ray emissive material and a second surface portion made of a heat emissive material comprising at least one of hafnium boride, hafnium oxide, hafnium nitride, hafnium silicide, and hafnium aluminide. (U.K.)

  6. Materials properties of hafnium and zirconium silicates: Metal interdiffusion and dopant penetration studies

    Science.gov (United States)

    Quevedo Lopez, Manuel Angel

    Hafnium and Zirconium based gate dielectrics are considered potential candidates to replace SiO2 or SiON as the gate dielectric in CMOS processing. Furthermore, the addition of nitrogen into this pseudo-binary alloy has been shown to improve their thermal stability, electrical properties, and reduce dopant penetration. Because CMOS processing requires high temperature anneals (up to 1050°C), it is important to understand the diffusion properties of any metal associated with the gate dielectric in silicon at these temperatures. In addition, dopant penetration from the doped polysilicon gate into the Si channel at these temperatures must also be studied. Impurity outdiffusion (Hf, Zr) from the dielectric, or dopant (B, As, P) penetration through the dielectric into the channel region would likely result in deleterious effects upon the carrier mobility. In this dissertation extensive thermal stability studies of alternate gate dielectric candidates ZrSixOy and HfSixO y are presented. Dopant penetration studies from doped-polysilicon through HfSixOy and HfSixOyNz are also presented. Rutherford Backscattering Spectroscopy (RBS), Heavy Ion RBS (HI-RBS), X-ray Photoelectron Spectroscopy (XPS), High Resolution Transmission Electron Microscopy (HR-TEM), and Time of Flight and Dynamic Secondary Ion Mass Spectroscopy (ToF-SIMS, D-SIMS) methods were used to characterize these materials. The dopant diffusivity is calculated by modeling of the dopant profiles in the Si substrate. In this disseration is reported that Hf silicate films are more stable than Zr silicate films, from the metal interdiffusion point of view. On the other hand, dopant (B, As, and P) penetration is observed for HfSixO y films. However, the addition of nitrogen to the Hf - Si - O systems improves the dopant penetration properties of the resulting HfSi xOyNz films.

  7. Single-Pass Percutaneous Liver Biopsy for Diffuse Liver Disease Using an Automated Device: Experience in 154 Procedures

    International Nuclear Information System (INIS)

    Rivera-Sanfeliz, Gerant; Kinney, Thomas B.; Rose, Steven C.; Agha, Ayad K.M.; Valji, Karim; Miller, Franklin J.; Roberts, Anne C.

    2005-01-01

    Purpose: To describe our experience with ultrasound (US)-guided percutaneous liver biopsies using the INRAD 18G Express core needle biopsy system.Methods: One hundred and fifty-four consecutive percutaneous core liver biopsy procedures were performed in 153 men in a single institution over 37 months. The medical charts, pathology reports, and radiology files were retrospectively reviewed. The number of needle passes, type of guidance, change in hematocrit level, and adequacy of specimens for histologic analysis were evaluated.Results: All biopsies were performed for histologic staging of chronic liver diseases. The majority of patients had hepatitis C (134/153, 90.2%). All patients were discharged to home after 4 hr of postprocedural observation. In 145 of 154 (94%) biopsies, a single needle pass was sufficient for diagnosis. US guidance was utilized in all but one of the procedures (153/154, 99.4%). The mean hematocrit decrease was 1.2% (44.1-42.9%). Pain requiring narcotic analgesia, the most frequent complication, occurred in 28 of 154 procedures (18.2%). No major complications occurred. The specimens were diagnostic in 152 of 154 procedures (98.7%).Conclusions: Single-pass percutaneous US-guided liver biopsy with the INRAD 18G Express core needle biopsy system is safe and provides definitive pathologic diagnosis of chronic liver disease. It can be performed on an outpatient basis. Routine post-biopsy monitoring of hematocrit level in stable, asymptomatic patients is probably not warranted

  8. Humoral and cellular immune response in mice induced by the classical swine fever virus E2 protein fused to the porcine CD154 antigen.

    Science.gov (United States)

    Sordo, Yusmel; Suárez, Marisela; Caraballo, Rosalina; Sardina, Talía; Brown, Emma; Duarte, Carlos; Lugo, Joanna; Gil, Lázaro; Perez, Danny; Oliva, Ayme; Vargas, Milagros; Santana, Elaine; Valdés, Rodolfo; Rodríguez, María Pilar

    2018-03-01

    The development of subunit vaccines against classical swine fever is a desirable goal, because it allows discrimination between vaccinated and infected animals. In this study, humoral and cellular immune response elicited in inbred BALB/c mice by immunization with a recombinant classical swine fever virus (CSFV) E2 protein fused to porcine CD154 antigen (E2CD154) was assessed. This model was used as a predictor of immune response in swine. Mice were immunized with E2CD154 emulsified in Montanide ISA50V2 or dissolved in saline on days 1 and 21. Another group received E2His antigen, without CD154, in the same adjuvant. Montanide ISA50V2 or saline served as negative controls for each experimental group. Animals immunized with 12.5 and 2.5 μg/dose of E2CD154 developed the highest titers (>1:2000) of CSFV neutralizing antibodies. Moreover, CSFV specific splenocyte gamma-interferon production, measured after seven and twenty-eight days of immunization, was significantly higher in mice immunized with 12.5 μg of E2CD154. As a conclusion, E2CD154 emulsified in Montanide ISA50 V2 was able to induce a potent humoral and an early cellular immune response in inbred BALB/c mice. Therefore, this immunogen might be an appropriate candidate to elicit immune response in swine, control CSF disease and to eliminate CSFV in swine. Copyright © 2018 International Alliance for Biological Standardization. Published by Elsevier Ltd. All rights reserved.

  9. Suppression effect of silicon (Si on Er3+ 1.54μm excitation in ZnO thin films

    Directory of Open Access Journals (Sweden)

    Bo Xu

    2016-08-01

    Full Text Available We have investigated the photoluminescence (PL characteristics of ZnO:Er thin films on Si (100 single crystal and SiO2-on-silicon (SiO2 substrates, synthesized by radio frequency magnetron sputtering. Rutherford backscattering/channeling spectrometry (RBS, X-ray diffraction (XRD and atomic force microscope (AFM were used to analyze the properties of thin films. The diffusion depth profiles of Si were determined by second ion mass spectrometry (SIMS. Infrared spectra were obtained from the spectrometer and related instruments. Compared with the results at room temperature (RT, PL (1.54μm intensity increased when samples were annealed at 250°C and decreased when at 550°C. A new peak at 1.15μm from silicon (Si appeared in 550°C samples. The Si dopants in ZnO film, either through the diffusion of Si from the substrate or ambient, directly absorbed the energy of pumping light and resulted in the suppression of Er3+ 1.54μm excitation. Furthermore, the energy transmission efficiency between Si and Er3+ was very low when compared with silicon nanocrystal (Si-NC. Both made the PL (1.54μm intensity decrease. All the data in experiments proved the negative effects of Si dopants on PL at 1.54μm. And further research is going on.

  10. Orbital ordering in {sup 154}SmNiO{sub 3}

    Energy Technology Data Exchange (ETDEWEB)

    Medarde, M.; Rosenkranz, S. [Paul Scherrer Inst. (PSI), Villigen (Switzerland); Rodrigeuez-Carvajal, J. [Laboratoire Leon Brillouin (LLB) - Centre d`Etudes de Saclay, 91 - Gif-sur-Yvette (France); Lacorre, P. [Lab. Fluorures, LeMans (France); Trounov, V. [PNPI, Gatchina (Russian Federation); Fernandez-Diaz, M.T. [Institut Max von Laue - Paul Langevin, 75 - Paris (France)

    1997-09-01

    We have investigated the existence of a structural distortion associated to the k = (1/2 0 1/2) orbital ordering recently proposed to explain the magnetic structure of RNiO{sub 3} perovskites (R = rare earth). Our results on a {sup 154}SmNiO{sub 3} powder sample indicate that, if existing, the associated superstructure reflections are as a maximum 10{sup 4} times smaller than the largest nuclear reflection. (author) 2 figs., 3 refs.

  11. Enfoque terapéutico en 154 pacientes con acromegalia Therapeutic management in 154 acromegalic patients

    Directory of Open Access Journals (Sweden)

    Marcos P. Manavela

    2010-08-01

    Full Text Available La acromegalia es una enfermedad poco frecuente producida en más del 95% de los casos por un tumor hipofisario secretor de hormona de crecimiento (GH. Las manifestaciones clínicas están asociadas a síntomas locales por crecimiento del tumor o a las consecuencias orgánicas y metabólicas secundarias a la hipersecreción de GH. Debido a la alta morbilidad y mortalidad asociadas a la acromegalia, un tratamiento individualizado y optimizado para cada paciente es fundamental. Informamos el enfoque terapéutico de nuestro servicio de endocrinología en la atención de 154 pacientes con acromegalia. Utilizando criterios bioquímicos estrictos, con la cirugía logramos un 32% de remisión global, tasa relativamente baja debido fundamentalmente a que la mayor parte de los pacientes presentaban macroadenomas con un alto porcentaje de invasividad local. Con radioterapia complementaria o como tratamiento inicial se logró la remisión en el 65.4% de los pacientes irradiados. El 14.0% de los pacientes controlaron la enfermedad utilizando agonistas dopaminérgicos solos o combinados con otra droga, mientras que aquellos que utilizaron análogos de la somatostatina normalizaron los parámetros bioquímicos en un 45.7% de los casos. En conclusión, con los diferentes tratamientos utilizados obtuvimos el control de la acromegalia en el 55.2% de los casos, esperando optimizar el tratamiento de estos pacientes en la medida en que contemos con y tengamos acceso a nuevas herramientas terapéuticas.Acromegaly is a chronic, invalidating disease due in over 95% of cases to a growth hormone (GH secreting pituitary adenoma. Its clinical manifestations are associated to local complications related to the tumor growth and/or to the metabolic consequences of GH excess. We report here our experience on 154 acromegalic patients. Surgical remission rate using stringent biochemical criteria was 32%, a figure relatively low due to the great number of patients bearing

  12. Lifetime embrittlement of reactor core materials

    International Nuclear Information System (INIS)

    Kreyns, P.H..; Bourgeois, W.F.; Charpentier, P.L.; Kammenzind, B.F.; Franklin, D.G.; White, C.J.

    1994-08-01

    Over a core lifetime, the reactor materials Zircaloy-2, Zircaloy-4, and hafnium may become embrittled due to the absorption of corrosion- generated hydrogen and to neutron irradiation damage. Results are presented on the effects of fast fluence on the fracture toughness of wrought Zircaloy-2, Zircaloy-4, and hafnium; Zircaloy-4 to hafnium butt welds; and hydrogen precharged beta treated and weld metal Zircaloy-4 for fluences up to a maximum of approximately 150 x 10 24 n/M 2 (> 1 Mev). While Zircaloy-4 did not exhibit a decrement in K IC due to irradiation, hafnium and butt welds between hafnium and Zircaloy-4 are susceptible to embrittlement with irradiation. The embrittlement can be attributed to irradiation strengthening, which promotes cleavage fracture in hafnium and hafnium-Zircaloy welds, and, in part, to the lower chemical potential of hydrogen in Zircaloy-4 compared to hafnium, which causes hydrogen, over time, to drift from the hafnium end toward the Zircaloy-4 end and to precipitate at the interface between the weld and base-metal interface. Neutron radiation apparently affects the fracture toughness of Zircaloy-2, Zircaloy-4, and hafnium in different ways. Possible explanations for these differences are suggested. It was found that Zircaloy-4 is preferred over Zircaloy-2 in hafnium-to- Zircaloy butt-weld applications due to its absence of a radiation- induced reduction in K IC plus its lower hydrogen absorption characteristics compared with Zircaloy-2

  13. The energy landscape of glassy dynamics on the amorphous hafnium diboride surface

    International Nuclear Information System (INIS)

    Nguyen, Duc; Girolami, Gregory S.; Mallek, Justin; Cloud, Andrew N.; Abelson, John R.; Lyding, Joseph; Gruebele, Martin

    2014-01-01

    Direct visualization of the dynamics of structural glasses and amorphous solids on the sub-nanometer scale provides rich information unavailable from bulk or conventional single molecule techniques. We study the surface of hafnium diboride, a conductive ultrahigh temperature ceramic material that can be grown in amorphous films. Our scanning tunneling movies have a second-to-hour dynamic range and single-point current measurements extend that to the millisecond-to-minute time scale. On the a-HfB 2 glass surface, two-state hopping of 1–2 nm diameter cooperatively rearranging regions or “clusters” occurs from sub-milliseconds to hours. We characterize individual clusters in detail through high-resolution (<0.5 nm) imaging, scanning tunneling spectroscopy and voltage modulation, ruling out individual atoms, diffusing adsorbates, or pinned charges as the origin of the observed two-state hopping. Smaller clusters are more likely to hop, larger ones are more likely to be immobile. HfB 2 has a very high bulk glass transition temperature T g , and we observe no three-state hopping or sequential two-state hopping previously seen on lower T g glass surfaces. The electronic density of states of clusters does not change when they hop up or down, allowing us to calibrate an accurate relative z-axis scale. By directly measuring and histogramming single cluster vertical displacements, we can reconstruct the local free energy landscape of individual clusters, complete with activation barrier height, a reaction coordinate in nanometers, and the shape of the free energy landscape basins between which hopping occurs. The experimental images are consistent with the compact shape of α-relaxors predicted by random first order transition theory, whereas the rapid hopping rate, even taking less confined motion at the surface into account, is consistent with β-relaxations. We make a proposal of how “mixed” features can show up in surface dynamics of glasses

  14. Scaffold protein JLP mediates TCR-initiated CD4+T cell activation and CD154 expression.

    Science.gov (United States)

    Yan, Qi; Yang, Cheng; Fu, Qiang; Chen, Zhaowei; Liu, Shan; Fu, Dou; Rahman, Rahmat N; Nakazato, Ryota; Yoshioka, Katsuji; Kung, Sam K P; Ding, Guohua; Wang, Huiming

    2017-07-01

    CD4 + T-cell activation and its subsequent induction of CD154 (CD40 ligand, CD40L) expression are pivotal in shaping both the humoral and cellular immune responses. Scaffold protein JLP regulates signal transduction pathways and molecular trafficking inside cells, thus represents a critical component in maintaining cellular functions. Its role in regulating CD4 + T-cell activation and CD154 expression, however, is unclear. Here, we demonstrated expression of JLP in mouse tissues of lymph nodes, thymus, spleen, and also CD4 + T cells. Using CD4+ T cells from jlp-deficient and jlp-wild-type mice, we demonstrated that JLP-deficiency impaired T-cell proliferation, IL-2 production, and CD154 induction upon TCR stimulations, but had no impacts on the expression of other surface molecules such as CD25, CD69, and TCR. These observed impaired T-cell functions in the jlp-/- CD4 + T cells were associated with defective NF-AT activation and Ca 2 + influx, but not the MAPK, NF-κB, as well as AP-1 signaling pathways. Our findings indicated that, for the first time, JLP plays a critical role in regulating CD4 + T cells response to TCR stimulation partly by mediating the activation of TCR-initiated Ca 2+ /NF-AT. Copyright © 2017 Elsevier Ltd. All rights reserved.

  15. 18 CFR 154.208 - Service of tariff filings on customers and other parties.

    Science.gov (United States)

    2010-04-01

    ... SCHEDULES AND TARIFFS Procedures for Changing Tariffs § 154.208 Service of tariff filings on customers and... customers and state regulatory commissions that have made a standing request for such service. (c) Within... section, service upon the designated recipient will be deemed service upon the customer or other party. (e...

  16. 32 CFR 154.18 - Certain positions not necessarily requiring access to classified information.

    Science.gov (United States)

    2010-07-01

    ... Directive 5210.65. 1 1 See footnote 1 to § 154.2(c). (l) Education and orientation personnel. Persons selected for duties in connection with programs involving the education and orientation of military... reliability and shall be evaluated on a continuing basis at the supervisory level to ensure that they continue...

  17. Suppression effect of silicon (Si) on Er{sup 3+} 1.54μm excitation in ZnO thin films

    Energy Technology Data Exchange (ETDEWEB)

    Xu, Bo; Lu, Fei, E-mail: lufei@sdu.edu.cn; Fan, Ranran [School of Information Science and Engineering, Shandong University, Jinan, Shandong 250100 (China); Ma, Changdong [Department of Radiation Oncology, Qilu Hospital, Shandong University, Jinan, Shandong 250100 (China)

    2016-08-15

    We have investigated the photoluminescence (PL) characteristics of ZnO:Er thin films on Si (100) single crystal and SiO{sub 2}-on-silicon (SiO{sub 2}) substrates, synthesized by radio frequency magnetron sputtering. Rutherford backscattering/channeling spectrometry (RBS), X-ray diffraction (XRD) and atomic force microscope (AFM) were used to analyze the properties of thin films. The diffusion depth profiles of Si were determined by second ion mass spectrometry (SIMS). Infrared spectra were obtained from the spectrometer and related instruments. Compared with the results at room temperature (RT), PL (1.54μm) intensity increased when samples were annealed at 250°C and decreased when at 550°C. A new peak at 1.15μm from silicon (Si) appeared in 550°C samples. The Si dopants in ZnO film, either through the diffusion of Si from the substrate or ambient, directly absorbed the energy of pumping light and resulted in the suppression of Er{sup 3+} 1.54μm excitation. Furthermore, the energy transmission efficiency between Si and Er{sup 3+} was very low when compared with silicon nanocrystal (Si-NC). Both made the PL (1.54μm) intensity decrease. All the data in experiments proved the negative effects of Si dopants on PL at 1.54μm. And further research is going on.

  18. Study of association of CD40-CD154 gene polymorphisms with disease susceptibility and cardiovascular risk in Spanish rheumatoid arthritis patients.

    Directory of Open Access Journals (Sweden)

    Mercedes García-Bermúdez

    Full Text Available Rheumatoid arthritis (RA is a chronic inflammatory disease associated with increased cardiovascular (CV mortality. Since CD40-CD154 binding has direct consequences on inflammation process initiation, we aimed to replicate previous findings related to disease susceptibility in Spanish RA population. Furthermore, as the major complication in RA disease patients is the development of CV events due to accelerated atherosclerosis, and elevated levels of CD40L/CD154 are present in patients with acute myocardial infarction, we assessed the potential association of CD40 and CD154/CD40L gene variants with CV risk in Spanish RA patients.One thousand five hundred and seventy-five patients fulfilling the 1987 ACR classification criteria for RA and 1600 matched controls were genotyped for the CD40 rs1883832, rs4810485 and rs1535045 and CD154 rs3092952 and rs3092920 gene polymorphisms, using predesigned TaqMan single nucleotide polymorphism genotyping assays. Afterwards, we investigated the influence of CD40-CD154 gene variants in the development of CV events. Also, in a subgroup of 273 patients without history of CV events, we assessed the influence of these polymorphisms in the risk of subclinical atherosclerosis determined by carotid ultrasonography.Nominally significant differences in the allele frequencies for the rs1883832 CD40 gene polymorphism between RA patients and controls were found (p=0.038. Although we did not observe a significant association of CD40-CD154 gene variants with the development of CV events, an ANCOVA model adjusted for sex, age at the time of the ultrasonography assessment, follow-up time, traditional CV risk factors and anti-cyclic citrullinated peptide antibodies disclosed a significant association (p=0.0047 between CD40 rs1535045 polymorphism and carotid intima media thickness, a surrogate marker of atherosclerosis.Data from our pilot study indicate a potential association of rs1883832 CD40 gene polymorphism with susceptibility

  19. An Auger electron spectroscopy study on the anodization process of high-quality thin-film capacitors made of hafnium

    International Nuclear Information System (INIS)

    Noya, Atsushi; Sasaki, Katsutaka; Umezawa, Toshiji

    1989-01-01

    Formation process of the anodic oxide film of hafnium for use as a thin-film capacitor has been examined by the current-voltage characteristics of the anodization and the in-depth analysis of formed oxide using Auger electron spectroscopy. It is found that the oxide growth obeys three different rate laws such as the linear rate law at first and next the parabolic rate law during the constant current anodization, and then the reciprocal logarithmic rate law during the constant voltage anodization following after the constant current process. From the Auger electron spectroscopy analysis, it is found that the shape of the compositional depth profile of the grown oxide film varies associating with the rate law of oxidation obeyed. The variation of depth profile correlating with the rate law is discussed with respect to each elementary process such as the transport and/or the reaction of chemical species interpreted from the over-all behavior of anodization process. It is revealed that the stoichiometric film having an interface with sharp transition, which is favorable for obtaining excellent electrical properties of the capacitor, can be obtained under the condition that the phase-boundary reaction is the rate-determining step of the anodization. The constant voltage anodization process also satisfies such circumstances and therefore can be favorable method for preparing highquality thin-film capacitors. (author)

  20. The Level of Europium-154 Contaminating Samarium-153-EDTMP Activates the Radiation Alarm System at the US Homeland Security Checkpoints

    Directory of Open Access Journals (Sweden)

    Mohammed Najeeb Al Hallak

    2009-08-01

    Full Text Available 153Sm-EDTMP is a radiopharmaceutical composed of EDTMP (ethylenediamine-tetramethylenephosphonate and Samarium-153 [1]. 153Sm-EDTMP has an affinity for skeletal tissue and concentrates in areas with increased bone turnover; thus, it is successfully used in relieving pain related to diffuse bone metastases [1]. The manufacturing process of 153Sm-EDTMP leads to contamination with 154Eu (Europium-154 [2]. A previous study only alluded to the retention of 154Eu in the bones after receiving treatment with 153Sm-EDTMP [2]. Activation of the alarm at security checkpoints after 153Sm-EDTMP therapy has not been previously reported. Two out of 15 patients who received 153Sm-EDTMP at Roger Maris Cancer Center (Fargo, N. Dak., USA activated the radiation activity sensors while passing through checkpoints; one at a US airport and the other while crossing theAmerican-Canadian border. We assume that the 154Eu which remained in the patients’ bones activated the sensors. Methods: In order to investigate this hypothesis, we obtained the consent from 3 of our 15 patients who received 153Sm-EDTMP within the previous 4 months to 2 years, including the patient who had activated the radiation alarm at the airport. The patients were scanned with a handheld detector and a gamma camera for energies from 511 keV to 1.3 MeV. Results: All three patients exhibited identical spectral images, and further analysis showed that the observed spectra are the result of 154Eu emissions. Conclusion: Depending on the detection thresholds and windows used by local and federal authorities, the remaining activity of 154Eu retained in patients who received 153Sm-EDTMP could be sufficient enough to increase the count rates above background levels and activate the sensors. At Roger Maris Cancer Center, patients are now informed of the potential consequences of 153Sm-EDTMP therapy prior to initiating treatment. In addition, patients treated with 153Sm-EDTMP at Roger Maris Cancer Center

  1. IL-6 signaling by STAT3 participates in the change from hyperplasia to neoplasia in NRP-152 and NRP-154 rat prostatic epithelial cells

    International Nuclear Information System (INIS)

    Barton, Beverly E; Murphy, Thomas F; Adem, Patricia; Watson, Richard A; Irwin, Robert J; Huang, Hosea F

    2001-01-01

    STAT3 phosphorylation is associated with the neoplastic state in many types of cancer, including prostate cancer. We investigated the role of IL-6 signaling and phosphorylation of STAT3 in 2 rat prostatic epithelial lines. NRP-152 and NRP-154 cells were derived from the same rat prostate, yet the NRP-152 cells are not tumorigenic while the NRP-154 cells are tumorigenic. These lines are believed to represent 2 of the stages in the development of prostate cancer, hyperplasia and neoplasia. Differences in signaling pathways should play a role in the 2 phenotypes, hyperplastic and neoplastic. We looked at the phosphorylation state of STAT3 by intracellular flow cytometry, using phospho-specific antibodies to STAT3. We used the same method to examine IL-6 production by the cell lines. We also measured apoptosis by binding of fluorescent annexin V to the cells. Although both cells lines made IL-6 constitutively, phosphorylated-STAT3 was present in untreated NRP-154 cells, but not in NRP-152 cells. Treatment with dexamethasone inhibited the IL-6 production of NRP-152 cells, but enhanced that of NRP-154 cells. Treatment with the JAK2 inhibitor AG490 induced apoptosis in NRP-152, but not NRP-154 cells. We conclude from these experiments that STAT3 activity plays a role in the phenotype of NRP-154 cell, but not NRP-152 cells. The significance of alternative IL-6 signaling pathways in the different phenotypes of the 2 cell lines is discussed

  2. Contribution towards ALD and MOCVD of rare earth oxides and hafnium oxide. From precursor evaluation to process development and thin film characterization

    International Nuclear Information System (INIS)

    Xu, Ke

    2013-01-01

    elements for ALD applications. A possible synthesis route is the salt metatheses route. It could be expected that the monodentate guanidine ligand would provide increased reactivity towards water, where the bulky guanidine ligands will shield the RE center providing self-limiting growth behavior. In Chapter 4 and 7, ALD of rare earth oxides and hafnium oxide using corresponding guanidinate precursors are in detail investigated. According to the measurements, these processes are true ALD processes with broad ALD windows, high growth per cycle in the saturated area. Furthermore, the rare earth guanidinate and hafnium guanidinate precursors exhibit matching ALD window in the temperature range of 200 - 225 C. This motivated us to deposite trinary oxide thin films (HfREOx) using corresponding precursor combinations.

  3. Dual function of the hemagglutinin H5 fused to chicken CD154 in a ...

    African Journals Online (AJOL)

    Dual function of the hemagglutinin H5 fused to chicken CD154 in a potential strategy of DIVA against avian influenza disease: preliminary study. AG Pose, ES Rodriguez, AC Mendez, JN Gomez, AV Redondo, ER Rodriguez, EMG Ramos, AA Gutierrez, MPR Molto, DG Roche, YS Ugalde, AM Lopez ...

  4. Nano-crystals of cerium–hafnium binary oxide: Their size-dependent structure

    Energy Technology Data Exchange (ETDEWEB)

    Raitano, Joan M. [Department of Applied Physics and Applied Mathematics, Materials Science and Engineering Program, Columbia University, New York, NY 10027 (United States); Khalid, Syed [National Synchrotron Light Source, Brookhaven National Laboratory, Upton, NY 11973 (United States); Marinkovic, Nebojsa [Chemical Engineering Department, Columbia University, 500 W 120th St, Mudd 801, New York, NY 10027 (United States); Chan, Siu-Wai, E-mail: sc174@columbia.edu [Department of Applied Physics and Applied Mathematics, Materials Science and Engineering Program, Columbia University, New York, NY 10027 (United States)

    2015-09-25

    Highlights: • (1 − x)CeO{sub 2}–xHfO{sub 2} was precipitated (0 < x < 1) and calcined in air. • For x ⩽ 0.14, crystallites ⩽140 nm in size exhibit only the fluorite structure. • This low hafnia solubility is attributable to no auto-reduction (Ce{sup 3+} = 0). • The low solubility is also due to the high temperature required for homogenization. • Coarsening is lessened as Hf{sup 4+} ions slow cation diffusion in these crystallites. - Abstract: Cerium oxide (CeO{sub 2}, “ceria”) and hafnium oxide (HfO{sub 2}, “hafnia”) were aqueously co-precipitated and subsequently calcined to allow for homogenization. The size of the (1−x)CeO{sub 2}–xHfO{sub 2} crystallites, determined by the Scherrer equation, varied from 140 nm for x = 0 to 15 nm for x = 0.73. For x ⩽ 0.14, only cubic structures are visible in X-ray diffractograms, and the lattice parameters are consistent with the values expected for structurally cubic solid solutions of hafnia in ceria. At x = 0.26, tetragonal and monoclinic phases nucleated with the former not being observed in the bulk phase diagram for ceria–hafnia. Therefore, the solubility limit of the cubic structure is between x = 0.14 and x = 0.26 for 40–61 nm crystallites, the sizes of these respective compositions. More specifically, for the 40 nm crystallites of x = 0.26 (1 − x)CeO{sub 2}–xHfO{sub 2}, 15% of the hafnia remains in a structurally cubic solid solution with ceria based on the observed cubic lattice parameter. The compositional domain for the cubic fluorite structure in this study is narrower than other nanostructured (1 − x)CeO{sub 2}–xHfO{sub 2} studies, especially studies with crystallite sizes less than 10 nm, but wider than observed in the bulk and helps to expand the size regime over which the relationship between crystallite size and phase stability is known. The extent of this cubic-structure domain is mainly attributable to the intermediate crystallite size and the roughly zero Ce{sup 3

  5. Isotope shifts and hyperfine splittings in 144-154Sm I

    International Nuclear Information System (INIS)

    England, J.G.; Grant, I.S.; Newton, G.W.A.; Walker, P.M.

    1990-01-01

    The isotope shifts and hyperfine splittings have been measured in 144-154 Sm I using the crossed-beam laser fluorescence method. Transitions at 598.98 nm and 570.68 nm were investigated for all isotopes except 146 Sm and 153 Sm, in which measurements were only obtained at 570.68 nm. Laser-induced fluorescence has not previously been reported for 145 Sm. The magnetic dipole and electric quadrupole moments of the odd isotopes and the changes in mean square radii of the even ones are shown to be consistent with the information obtained from nuclear spectroscopy. (author)

  6. Mg-Al layered double hydroxide intercalated with sodium lauryl sulfate as a sorbent for 152+154Eu from aqueous solutions

    International Nuclear Information System (INIS)

    Mahmoud, M.R.; Someda, H.H.

    2012-01-01

    In the present study, Mg-Al layered double hydroxide intercalated with nitrate anions (LDH-NO 3 ) was synthesized, modified with the anionic surfactant, sodium lauryl sulfate, and applied for the removal of 152+154 Eu from aqueous solutions. Modification of the as-synthesized Mg-Al layered double hydroxide was carried out at surfactant concentration of 0.01 M (the organo-LDH produced denoted LDH-NaLS). The as-synthesized and surfactant-intercalated LDHs were characterized by FT-IR and energy-dispersive X-ray spectroscopy techniques. The effect of some variables such as solution pH, contact time and sorbate concentration on removal of 152+154 Eu was investigated. The kinetic data obtained were well fitted by the pseudo-second-order kinetic model rather than the pseudo-first-order model. Intraparticle diffusion model showed that sorption of 152+154 Eu proceed by intraparticle diffusion together with boundary layer diffusion. Experimental isotherm data were well described by Langmuir model. Organo-LDH was found to have higher capacity (156.45 mg g -1 ) for europium than the as-synthesized LDH-NO 3 (119.56 mg g -1 ). Comparing LDHs capacities obtained for Eu(III) in the present work with other sorbents reported in literature indicated that LDHs have the highest capacities. Application of the developed process for removal of 152+154 Eu(III) from radioactive process wastewaters was also studied and the obtained results revealed that these LDHs are promising materials for treatment of radioactive wastewaters. (author)

  7. L2₁ and XA Ordering Competition in Hafnium-Based Full-Heusler Alloys Hf₂VZ (Z = Al, Ga, In, Tl, Si, Ge, Sn, Pb).

    Science.gov (United States)

    Wang, Xiaotian; Cheng, Zhenxiang; Wang, Wenhong

    2017-10-20

    For theoretical designing of full-Heusler based spintroinc materials, people have long believed in the so-called Site Preference Rule (SPR). Very recently, according to the SPR, there are several studies on XA-type Hafnium-based Heusler alloys X₂YZ, i.e., Hf₂VAl, Hf₂CoZ (Z = Ga, In) and Hf₂CrZ (Z = Al, Ga, In). In this work, a series of Hf₂-based Heusler alloys, Hf₂VZ (Z = Al, Ga, In, Tl, Si, Ge, Sn, Pb), were selected as targets to study the site preferences of their atoms by first-principle calculations. It has been found that all of them are likely to exhibit the L2₁-type structure instead of the XA one. Furthermore, we reveal that the high values of spin-polarization of XA-type Hf₂VZ (Z = Al, Ga, In, Tl, Si, Ge, Sn, Pb) alloys have dropped dramatically when they form the L2₁-type structure. Also, we prove that the electronic, magnetic, and physics nature of these alloys are quite different, depending on the L2₁-type or XA-type structures.

  8. 33 CFR Appendix D to Part 154 - Training Elements for Oil Spill Response Plans

    Science.gov (United States)

    2010-07-01

    ... Appendix D to Part 154—Training Elements for Oil Spill Response Plans 1. General 1.1The portion of the plan dealing with training is one of the key elements of a response plan. This concept is clearly expressed by... that the plans often do not provide sufficient information in the training section of the plan for...

  9. Dual function of the hemagglutinin H5 fused to chicken CD154 in a ...

    African Journals Online (AJOL)

    Dual function of the hemagglutinin H5 fused to chicken CD154 in a potential strategy of DIVA against avian influenza disease: preliminary study. ... The PDF file you selected should load here if your Web browser has a PDF reader plug-in installed (for example, a recent version of Adobe Acrobat Reader). If you would like ...

  10. Growth of conductive HfO{sub 2-x} thin films by reactive molecular beam epitaxy

    Energy Technology Data Exchange (ETDEWEB)

    Hildebrandt, Erwin; Kurian, Jose; Alff, Lambert [Institut fuer Materialwissenschaft, TU Darmstadt (Germany); Kleebe, Hans-Joachim [Institut fuer Angewandte Geowissenschaften, TU Darmstadt (Germany)

    2009-07-01

    Thin films of oxygen deficient hafnium oxide were grown on single crystal c-cut and r-cut sapphire substrates by reactive molecular beam epitaxy. The oxidation conditions during growth were varied within a wide range using RF-activated oxygen. Hafnium oxide thin films were characterized using X-ray diffraction, resistivity measurements ({rho}-T) and transmission electron microscopy (TEM). The results show a dramatic increase in conductivity of the deposited oxygen deficient hafnium oxide thin films with decreasing oxidation conditions during growth. The electrical properties of deficient hafnium oxide thin films varied from insulating over semiconducting to conducting. X-ray diffraction data as well as TEM data rule out the possibility of conductivity due to metallic hafnium.

  11. Feeding times of high spin states in sup(152,154)Dy: Probes of nuclear structure above the yrast line

    International Nuclear Information System (INIS)

    Azgui, F.; Emling, H.; Grosse, E.; Michel, C.; Simon, R.S.; Spreng, W.; Wollersheim, H.J.; Khoo, T.L.; Chowdhury, P.; Frekers, D.; Janssens, R.V.F.; Pakkanen, A.; Daly, P.J.; Kortelahti, M.; Schwalm, D.; Seiler-Clark, G.

    1985-01-01

    Measurements of feeding times of high spin yrast states up to spin 30 (h/2π) in 154 Dy and 36 (h/2π) in 152 Dy were utilized to obtain information about possible spin dependent shape changes. The reactions 25 Mg ( 134 Xe, 5n), 124 Sn ( 34 S, 4n) and 25 Mg ( 132 Xe, 5n), 122 Sn ( 34 S, 4n) were used to populate the high spin states in 154 Dy and 152 Dy, respectively. Feeding times as well as lifetimes were determined with the recoil distance technique. In 152 Dy only long feeding times (>=10 ps) could be identified, indicating that the aligned-particle yrast states are fed through configurations of similar character, with little direct population from collective cascades in the continuum region. In 154 Dy discrete states with I<=30 (h/2π) have lifetimes which are characteristically collective, whereas the preyrast cascades exhibit both fast (< or approx.1 ps) and slow (proportional10 ps) feeding components. The latter imply a change with increasing spin from collective to aligned-particle character, probably associated with a prolate to oblate shape transition. (orig.)

  12. Hafnium in peralkaline and peraluminous boro-aluminosilicate glass, and glass subcomponents: a solubility study

    International Nuclear Information System (INIS)

    Davis, Linda L.; Darab, John G.; Qian, Maoxu; Zhao, Donggao; Palenik, Christopher S.; Li, Hong; Strachan, Denis M.; Li, Liyu

    2003-01-01

    A relationship between the solubility of hafnia (HfO2) and the host glass composition was explored by determining the solubility limits of HfO2 in peralkaline and peraluminous borosilicate glasses in the system SiO2-Al2O3-B2O3-Na2O, and in glasses in the system SiO2-Na2O-Al2O3 in air at 1450 C. The only Hf-bearing phase to crystallize in the peralkaline borosilicate melts is hafnia, while in the boron-free melts sodium-hafnium silicates crystallize. All peraluminous borosilicate melts crystallize hafnia, but the slightly peraluminous glasses also have sector-zoned hafnia crystals that contain Al and Si. The more peraluminous borosilicate glasses also crystallize a B-containing mullite. The general morphology of the hafnia crystals changes as peralkalinity (Na2O/(Na2O+Al2O3)) decreases, as expected in melts with increasing viscosity. In all of the glasses with Na2O > Al2O3, the solubility of hafnia is linearly and positively correlated with Na2O/(Na2O + Al2O3) or Na2O - Al2O3 (excess sodium), despite the presence of 5 to 16 mol% B2O3. The solubility of hafnia is higher in the sodium-aluminum borosilicate glasses than in the sodium-aluminosilicate glasses, suggesting that the boron is enhancing the effect that excess sodium has on the incorporation of Hf into the glass structure. The results of this solubility study are compared to other studies of high-valence cation solubility in B-free silicate melts. From this, for peralkaline B-bearing glasses, it is shown that, although the solubility limits are higher, the solution behavior of hafnia is the same as in B-free silicate melts previously studied. By comparison, also, it is shown that in peraluminous melts, there must be a different solution mechanism for hafnia: different than for peralkaline sodium-aluminum borosilicate glasses and different than for B-free silicate melts studied by others

  13. Determination of the nuclear electric charge distribution of samarium isotopes 144, 148, 150, 152, 154 by the muonic atom method

    International Nuclear Information System (INIS)

    Barreau, Pierre.

    1977-01-01

    The theory of the nucleus-negative muon system in the case of electrical interactions is discussed. The interactions of muons with the samarium isotopes 152, 154, 144, 148, 150 are investigated. After a description of the experimental device, from muon beam production to data acquisition (detection of the gamma spectra), the results are analyzed and the nuclear charge distribution parameters determined: for each isotope the absolute value of c (half-density radius) and t (skin thickness); for 152 Sm and 154 Sm the parameter β 2 (quadrupolar defomation). Nuclear polarization was accounted for throughout the analysis [fr

  14. Mutations in Ovis aries TMEM154 are associated with lower small ruminant lentivirus proviral concentration in one sheep flock.

    Science.gov (United States)

    Alshanbari, F A; Mousel, M R; Reynolds, J O; Herrmann-Hoesing, L M; Highland, M A; Lewis, G S; White, S N

    2014-08-01

    Small ruminant lentivirus (SRLV), also called ovine progressive pneumonia virus or maedi-visna, is present in 24% of US sheep. Like human immunodeficiency virus, SRLV is a macrophage-tropic lentivirus that causes lifelong infection. The production impacts from SRLV are due to a range of disease symptoms, including pneumonia, arthritis, mastitis, body condition wasting and encephalitis. There is no cure and no effective vaccine for preventing SRLV infection. However, breed differences in prevalence and proviral concentration indicate a genetic basis for susceptibility to SRLV. Animals with high blood proviral concentration show increased tissue lesion severity, so proviral concentration represents a live animal test for control post-infection in terms of proviral replication and disease severity. Recently, it was found that sheep with two copies of TMEM154 haplotype 1 (encoding lysine at position 35) had lower odds of SRLV infection. In this study, we examined the relationship between SRLV control post-infection and variants in two genes, TMEM154 and CCR5, in four flocks containing 1403 SRLV-positive sheep. We found two copies of TMEM154 haplotype 1 were associated with lower SRLV proviral concentration in one flock (P < 0.02). This identified the same favorable diplotype for SRLV control post-infection as for odds of infection. However, frequencies of haplotypes 2 and 3 were too low in the other three flocks to test. The CCR5 promoter deletion did not have consistent association with SRLV proviral concentration. Future work in flocks with more balanced allele frequencies is needed to confirm or refute TMEM154 association with control of SRLV post-infection. Published 2014. This article is a U.S. Government work and is in the public domain in the USA. Animal Genetics published by John Wiley & Sons Ltd on behalf of Stichting International Foundation for Animal Genetics.

  15. Tumores de glândula parótida: estudo retrospectivo de 154 pacientes

    OpenAIRE

    Maahs, Gerson Schulz; Oppermann, Paula de Oliveira; Maahs, Lucas Gerhard Peter; Machado Filho, Geraldo; Ronchi, André Dajori

    2015-01-01

    INTRODUCTION: Benign tumors of the parotid gland comprise the majority of salivary gland tumors. OBJECTIVE: To review the clinical characteristics of parotid gland tumors submitted to surgical treatment by the same surgeon. METHODS: Retrospective study with 154 patients who had parotid gland tumors. Clinical and histological data, type of surgery, and complications were assessed and described. RESULTS: The main manifestation was a mass with a median evolution of 12 months for benign tumors an...

  16. Comparison of HfCl4, HfI4, TEMA-Hf, and TDMA-Hf as precursors in early growing stages of HfO2 films deposited by ALD: A DFT study

    International Nuclear Information System (INIS)

    Cortez-Valadez, M.; Fierro, C.; Farias-Mancilla, J.R.; Vargas-Ortiz, A.; Flores-Acosta, M.; Ramírez-Bon, R.; Enriquez-Carrejo, J.L.

    2016-01-01

    Highlights: • Hafnium oxide growth on Si(100) by atomic layer deposition was simulated. • The interface structure was considered as silicate and silicide. • The interface was studied employing DFT. • TDMA-Hf precursor show better interface stability. - Abstract: The final structure of HfO 2 films grown by atomic layer deposition (ALD) after reaction with OH − ions has been analyzed by DFT (density functional theory). The interaction of the precursors: HfCl 4 (hafnium tetrachloride), HfI 4 (hafnium tetraiodide), TEMA-Hf (tetrakis-ethylmethylamino hafnium), and TDMA-Hf (tetrakis-dimethylamino hafnium) with HO–H was studied employing the B3LYP (Becke 3-parameter, Lee–Yang–Parr) hybrid functional and the PBE (Perdew–Burke–Ernzerhof) generalized gradient functional. The structural evolution at the Si(100) surface has been analyzed by LDA (local density approximation). The structural parameters: bond length and bond angle, and the vibrational parameters for the optimized structures are also reported. The presence of hafnium silicate at the interface was detected. The infrared spectra and structural parameters obtained in this work agree with previously reported experimental results.

  17. Report on the intercomparison run IAEA-154 radionuclides in whey powder

    International Nuclear Information System (INIS)

    Cooper, E.L.; LaBrecque, J.J.; Dekner, R.; Reichel, F.; Schelenz, R.

    1988-09-01

    The results of the intercomparison on whey powder (IAEA-154) for the determination of elevated levels of radioactivity are reported. The data for thirty-one laboratories from sixteen different countries have been considered and include the determination of the following radionuclides: 134 Cs, 137 Cs, 40 K, 90 Sr. According to a statistical evaluation sufficient data for recommended mean values and confidence intervals have been received for: 134 Cs: 1355 Bq/kg (1295-1417); 137 Cs: 3749 Bq/kg (3613-3887); 40 K: 1575 Bq/kg (1511-1644); 90 Sr: 6.9 Bq/kg (6.0-8.0). Reference date: 31 August 1987. 3 refs, figs and tabs

  18. Complete and incomplete fusion dynamics in 19F + 154Sm system

    International Nuclear Information System (INIS)

    Singh, D.; Giri, Pankaj K.; Linda, Sneha B.

    2016-01-01

    Several experimental and theoretical studies based on spin distribution measurement have been carried out by using α-cluster structured projectile with different target nuclei but spin distribution measurement studies to localize the ℓ-window of CF and ICF by using non alpha cluster structured projectile scarcely exist in the literature. Therefore, to reach on some definite conclusion regarding the projectile structure and projectile energy effect on ICF dynamics especially by using non alpha cluster structured projectile, the spin distribution measurement of the evaporation residues produced through CF and ICF dynamics in the 19 F + 154 Sm system at projectile energies 110 and 100 MeV has been done

  19. Synthesis and characterization of hafnium carbide microcrystal chains with a carbon-rich shell via CVD

    International Nuclear Information System (INIS)

    Tian, Song; Li, Hejun; Zhang, Yulei; Liu, Sen; Fu, Yangxi; Li, Yixian; Qiang, Xinfa

    2013-01-01

    Graphical abstract: Novel HfC microcrystal chains have been synthesized via a catalyst-assisted chemical vapor deposition process. SEM results show the chains have a periodically changing diameter and a nanoscale sharpening tip. Analysis of TEM/SAED/EELS/EDX data shows the single-crystal chains grow along a [0 0 1] direction and consist of a HfC core and a thin carbon-rich shell with embedded HfC nanocrystallites surrounding the core. This work achieves the controllable preparation of nanoscale HfC sharpening tips for application as a point electron emission source and facilitates the application of HfC ultrafast laser-triggered tips in attosecond science. Highlights: •HfC microcrystal chains were synthesized by a catalyst-assisted CVD. •The chains grow along a [0 0 1] direction and have a periodically changing diameter. •Single-crystal HfC core is sheathed by a thin carbon-rich shell. •A growth mechanism model is proposed to explain the growth of microcrystal chians. •This work achieves the controllable preparation of nanoscale HfC sharpening tips. -- Abstract: Novel hafnium carbide (HfC) microcrystal chains, with a periodically changing diameter and a nanoscale sharpening tip at the chain end, have been synthesized via a catalyst-assisted chemical vapor deposition (CVD) process. The as-synthesized chains with many octahedral microcrystals have diameters of between several hundreds of nm and 6 μm and lengths of ∼500 μm. TEM diffraction studies show that the chains are single-crystalline HfC and preferentially grow along a [0 0 1] crystal orientation. TEM/EELS/EDX analysis proves the chains are composed of a HfC core and a thin (several tens of nm to 100 nm) carbon-rich shell with the embedded HfC nanocrystallites (typically below 10 nm) surrounding the core. The growth mechanism model for the chains based on the vapor–liquid–solid process, the vapor–solid process, and the HfC crystal growth characteristics is discussed

  20. Design of an Extractive Distillation Column for the Environmentally Benign Separation of Zirconium and Hafnium Tetrachloride for Nuclear Power Reactor Applications

    Directory of Open Access Journals (Sweden)

    Le Quang Minh

    2015-09-01

    Full Text Available Nuclear power with strengthened safety regulations continues to be used as an important resource in the world for managing atmospheric greenhouse gases and associated climate change. This study examined the environmentally benign separation of zirconium tetrachloride (ZrCl4 and hafnium tetrachloride (HfCl4 for nuclear power reactor applications through extractive distillation using a NaCl-KCl molten salt mixture. The vapor–liquid equilibrium behavior of ZrCl4 and HfCl4 over the molten salt system was correlated with Raoult’s law. The molten salt-based extractive distillation column was designed optimally using a rigorous commercial simulator for the feasible separation of ZrCl4 and HfCl4. The molten salt-based extractive distillation approach has many potential advantages for the commercial separation of ZrCl4 and HfCl4 compared to the conventional distillation because of its milder temperatures and pressure conditions, smaller number of required separation trays in the column, and lower energy requirement for separation, while still taking the advantage of environmentally benign feature by distillation. A heat-pump-assisted configuration was also explored to improve the energy efficiency of the extractive distillation process. The proposed enhanced configuration reduced the energy requirement drastically. Extractive distillation can be a promising option competing with the existing extraction-based separation process for zirconium purification for nuclear power reactor applications.

  1. Cobalt(II), nickel(II), copper(II), zinc(II) and hafnium(IV) complexes of N'-(furan-3-ylmethylene)-2-(4-methoxyphenylamino)acetohydrazide.

    Science.gov (United States)

    Emam, Sanaa M; El-Saied, Fathy A; Abou El-Enein, Saeyda A; El-Shater, Heba A

    2009-03-01

    Cobalt(II), nickel(II), copper(II), zinc(II) and hafnium(IV) complexes of furan-2-carbaldehyde 4-methoxy-N-anilinoacetohydrazone were synthesized and characterized by elemental and thermal (TG and DTA) analyses, IR, UV-vis and (1)H NMR spectra as well as magnetic moment and molar conductivity. Mononuclear complexes are obtained with 1:1 molar ratio except complexes 3 and 9 which are obtained with 1:2 molar ratios. The IR spectra of ligand and metal complexes reveal various modes of chelation. The ligand behaves as a neutral bidentate one and coordination occurs via the carbonyl oxygen atom and azomethine nitrogen atom. The ligand behaves also as a monobasic tridentate one and coordination occurs through the enolic oxygen atom, azomethine nitrogen atom and the oxygen atom of furan ring. Moreover, the ligand behaves as a neutral tridentate and coordination occurs via the carbonyl oxygen, azomethine nitrogen and furan oxygen atoms as well as a monobasic bidentate and coordination occurs via the enolic oxygen atom and azomethine nitrogen atom. The electronic spectra and magnetic moment measurements reveal that all complexes possess octahedral geometry except the copper complex 10 possesses a square planar geometry. The thermal studies showed the type of water molecules involved in metal complexes as well as the thermal decomposition of some metal complexes.

  2. Characterization of cytochrome P450 monooxygenase CYP154H1 from the thermophilic soil bacterium Thermobifida fusca

    NARCIS (Netherlands)

    Schallmey, Anett; den Besten, Gijs; Teune, Ite G. P.; Kembaren, Roga F.; Janssen, Dick B.

    Cytochrome P450 monooxygenases are valuable biocatalysts due to their ability to hydroxylate unactivated carbon atoms using molecular oxygen. We have cloned the gene for a new cytochrome P450 monooxygenase, named CYP154H1, from the moderately thermophilic soil bacterium Thermobifida fusca. The

  3. Comparison of HfCl4, HfI4, TEMA-Hf, and TDMA-Hf as precursors in early growing stages of HfO2 films deposited by ALD: A DFT study

    Science.gov (United States)

    Cortez-Valadez, M.; Fierro, C.; Farias-Mancilla, J. R.; Vargas-Ortiz, A.; Flores-Acosta, M.; Ramírez-Bon, R.; Enriquez-Carrejo, J. L.; Soubervielle-Montalvo, C.; Mani-Gonzalez, P. G.

    2016-06-01

    The final structure of HfO2 films grown by atomic layer deposition (ALD) after reaction with OH- ions has been analyzed by DFT (density functional theory). The interaction of the precursors: HfCl4 (hafnium tetrachloride), HfI4 (hafnium tetraiodide), TEMA-Hf (tetrakis-ethylmethylamino hafnium), and TDMA-Hf (tetrakis-dimethylamino hafnium) with HO-H was studied employing the B3LYP (Becke 3-parameter, Lee-Yang-Parr) hybrid functional and the PBE (Perdew-Burke-Ernzerhof) generalized gradient functional. The structural evolution at the Si(100) surface has been analyzed by LDA (local density approximation). The structural parameters: bond length and bond angle, and the vibrational parameters for the optimized structures are also reported. The presence of hafnium silicate at the interface was detected. The infrared spectra and structural parameters obtained in this work agree with previously reported experimental results.

  4. A spanish mineral of zirconium and hafnium. Separation of the two elements by liquid-liquid extraction, using tributyl phosphate as chelating agent; Beneficio de un mineral espanol de circonio-hafnio. Separacion de ambos elementos por extraccion liquido-liquido, empleando fosfato de tributilo como agente de quelacion

    Energy Technology Data Exchange (ETDEWEB)

    Ruiz Sanchez, F; Cruz Castillo, F. de la; Fernandez Cellini, R

    1962-07-01

    The zirconium and Hafnium oxides are obtained from a Spanish mineral of zircon with an average contest of 55% in ZrO{sub 2}-HfO{sub 2}. An alkaline fusion to open the mineral, followed by a purification by crystallization as (Zr O-Hf O)Cl{sub 2} H{sub 2}O or as (Zr-Hf) (SO{sub 4}){sub 2}. 4H{sub 2}O, is used. A discussion of the best experimental conditions for opening the mineral and of the purification method is made. (Author) 45 refs.

  5. 6-Peroxo-6-zirconium crown and its hafnium analogue embedded in a triangular polyanion: [M6(O2)6(OH)6(gamma-SiW10O36)3]18- (M = Zr, Hf).

    Science.gov (United States)

    Bassil, Bassem S; Mal, Sib Sankar; Dickman, Michael H; Kortz, Ulrich; Oelrich, Holger; Walder, Lorenz

    2008-05-28

    We have synthesized and structurally characterized the unprecedented peroxo-zirconium(IV) containing [Zr6(O2)6(OH)6(gamma-SiW10O36)3]18- (1). Polyanion 1 comprises a cyclic 6-peroxo-6-zirconium core stabilized by three decatungstosilicate units. We have also prepared the isostructural hafnium(IV) analogue [Hf6(O2)6(OH)6(gamma-SiW10O36)3]18- (2). We investigated the acid/base and redox properties of 1 by UV-vis spectroscopy and electrochemistry studies. Polyanion 1 represents the first structurally characterized Zr-peroxo POM with side-on, bridging peroxo units. The simple, one-pot synthesis of 1 and 2 involving dropwise addition of aqueous hydrogen peroxide could represent a general procedure for incorporating peroxo groups into a large variety of transition metal and lanthanide containing POMs.

  6. Comparison of HfCl{sub 4}, HfI{sub 4}, TEMA-Hf, and TDMA-Hf as precursors in early growing stages of HfO{sub 2} films deposited by ALD: A DFT study

    Energy Technology Data Exchange (ETDEWEB)

    Cortez-Valadez, M. [Departamento de Investigación en Física, Universidad de Sonora, Apdo. Postal 5-88, 83190 Hermosillo, Son. (Mexico); Fierro, C.; Farias-Mancilla, J.R. [Instituto de Ingeniería y Tecnología, Departamento de Física y Matemáticas, Universidad Autónoma de Ciudad Juárez, Av. del Charro 450, Cd. Juárez C.P. 32310, Chihuahua (Mexico); Vargas-Ortiz, A. [Universidad Autónoma de Sinaloa, Facultad de Ingeniería Mochis, Ciudad Universitaria, C.P. 81223 Los Mochis, Sinaloa (Mexico); Flores-Acosta, M. [Departamento de Investigación en Física, Universidad de Sonora, Apdo. Postal 5-88, 83190 Hermosillo, Son. (Mexico); Ramírez-Bon, R. [Centro de Investigación y Estudios Avanzados del IPN, Unidad Querétaro, Apdo. Postal 1-798, 76001 Querétaro, Qro. (Mexico); Enriquez-Carrejo, J.L. [Instituto de Ingeniería y Tecnología, Departamento de Física y Matemáticas, Universidad Autónoma de Ciudad Juárez, Av. del Charro 450, Cd. Juárez C.P. 32310, Chihuahua (Mexico); and others

    2016-06-15

    Highlights: • Hafnium oxide growth on Si(100) by atomic layer deposition was simulated. • The interface structure was considered as silicate and silicide. • The interface was studied employing DFT. • TDMA-Hf precursor show better interface stability. - Abstract: The final structure of HfO{sub 2} films grown by atomic layer deposition (ALD) after reaction with OH{sup −} ions has been analyzed by DFT (density functional theory). The interaction of the precursors: HfCl{sub 4} (hafnium tetrachloride), HfI{sub 4} (hafnium tetraiodide), TEMA-Hf (tetrakis-ethylmethylamino hafnium), and TDMA-Hf (tetrakis-dimethylamino hafnium) with HO–H was studied employing the B3LYP (Becke 3-parameter, Lee–Yang–Parr) hybrid functional and the PBE (Perdew–Burke–Ernzerhof) generalized gradient functional. The structural evolution at the Si(100) surface has been analyzed by LDA (local density approximation). The structural parameters: bond length and bond angle, and the vibrational parameters for the optimized structures are also reported. The presence of hafnium silicate at the interface was detected. The infrared spectra and structural parameters obtained in this work agree with previously reported experimental results.

  7. Transfer reactions in sup(32,36)S + sup(144,154)Sm

    International Nuclear Information System (INIS)

    Pacheco, A.J.; Tada, M. di; Fernandez Niello, J.; Testoni, J.E.

    1990-01-01

    The deformation of spherical nuclei in transfer reactions near to the coulomb barrier is studied. The sup(32,36)S + sup(144,154)Sm reactions were carried out using sup(32)S beams produced by TANDAR accelerator in Buenos Aires with energies of 148 MeV and 160 MeV and sup(36)S beams produced by tandem accelerator of Laboratorio Nazionale di Legnaro with energies of 142 MeV and 155 MeV. The angular distributions were measured for sup(32)S reaction using gas ionization chamber and position sensitive detector. The mass spectra of reaction products were obtained measuring time of flight between time detectors, in the sup(36)S reaction. (M.C.K.)

  8. Tat-haFGF14–154 Upregulates ADAM10 to Attenuate the Alzheimer Phenotype of APP/PS1 Mice through the PI3K-CREB-IRE1α/XBP1 Pathway

    Directory of Open Access Journals (Sweden)

    Tian Meng

    2017-06-01

    Full Text Available Acid fibroblast growth factor (aFGF has shown neuroprotection in Alzheimer’s disease (AD models in previous studies, yet its mechanism is still uncertain. Here we report that the efficacy of Tat-haFGF14–154 is markedly increased when loaded cationic liposomes for intranasal delivery are intranasally administered to APP/PS1 mice. Our results demonstrated that liposomal Tat-haFGF14–154 treatment significantly ameliorated behavioral deficits, relieved brain Aβ burden, and increased the expression and activity of disintegrin and metalloproteinase domain-containing protein 10 (ADAM10 in the brain. Tat-haFGF14–154 antagonized Aβ1–42-induced cell death and structural damage in rat primary neurons in an ADAM10-dependent manner, which, in turn, was promoted by the activation of XBP1 splicing and modulated by the PI3K-CREB pathway. Both knockdown of ADAM10 and inhibition of PI3K (LY294002 negated Tat-haFGF14–154 rescue. Thus, Tat-haFGF14–154 activates the IRE1α/XBP1 pathway of the unfolded protein response (UPR against the endoplasmic reticulum (ER stress induced by Aβ, and, subsequently, the nuclear translocation of spliced XBP1 (XBP1s promotes transcription of ADAM10. These results highlight the important role of ADAM10 and its activation through the PI3K-CREB-IRE1α/XBP1 pathway as a key factor in the mechanism of neuroprotection for Tat-haFGF14–154.

  9. Towards Superheavies: Spectroscopy of 94 < Z < 98, 150 < N < 154 Nuclei

    Directory of Open Access Journals (Sweden)

    Chowdhury P.

    2016-01-01

    nuclear structure studies are important testing grounds for theoretical models that aim to describe superheavy nuclei. To study the highest neutron orbitals (150 ≤ N ≤ 154, we have populated high angular momentum states in a series of Pu (Z = 94, Cm (Z = 96 and Cf (Z = 98 nuclei, via inelastic and transfer reactions, with heavy beams on long-lived radioactive actinide targets. Multiple collective excitation modes and structures were identified, and their configurations deduced. Quasiparticle alignments are mapped, with odd-A band structures helping identify specific orbital contributions via blocking arguments. Higher-order multipole shapes are observed to play a significant role in disentangling competing neutron and proton alignments. The N > 152 data provide new perspectives on physics beyond the N = 152 sub-shell gap.

  10. Corrosion resistant surface for vanadium nitride and hafnium nitride layers as function of grain size

    Science.gov (United States)

    Escobar, C. A.; Caicedo, J. C.; Aperador, W.

    2014-01-01

    In this research it was studied vanadium nitride (VN) and hafnium nitride (HfN) film, which were deposited onto silicon (Si (100)) and AISI 4140 steel substrates via r.f. magnetron sputtering technique in Ar/N2 atmosphere with purity at 99.99% for both V and Hf metallic targets. Both films were approximately 1.2±0.1 μm thick. The crystallography structures that were evaluated via X-ray diffraction analysis (XRD) showed preferential orientations in the Bragg planes VN (200) and HfN (111). The chemical compositions for both films were characterized by EDX. Atomic Force Microscopy (AFM) was used to study the morphology; the results reveal grain sizes of 78±2 nm for VN and 58±2 nm for HfN and roughness values of 4.2±0.1 nm for VN and 1.5±0.1 nm for HfN films. The electrochemical performance in VN and HfN films deposited onto steel 4140 were studied by Tafel polarization curves and impedance spectroscopy methods (EIS) under contact with sodium chloride at 3.5 wt% solution, therefore, it was found that the corrosion rate decreased about 95% in VN and 99% for HfN films in relation to uncoated 4140 steel, thus demonstrating, the protecting effect of VN and HfN films under a corrosive environment as function of morphological characteristics (grain size). VN(grain size)=78±2.0 nm, VN(roughness)=4.2±0.1 nm, VN(corrosion rate)=40.87 μmy. HfN(grain size)=58±2.0 nm, HfN(roughness)=1.5±0.1 nm, HfN(corrosion rate)=0.205 μmy. It was possible to analyze that films with larger grain size, can be observed smaller grain boundary thus generating a higher corrosion rate, therefore, in this work it was found that the HfN layer has better corrosion resistance (low corrosion rate) in relation to VN film which presents a larger grain size, indicating that the low grain boundary in (VN films) does not restrict movement of the Cl- ion and in this way the corrosion rate increases dramatically.

  11. Second proton and neutron alignments in the doubly-odd nuclei 154,156Tb

    International Nuclear Information System (INIS)

    Hartley, D.J.; Allen, J.L.; Brown, T.B.; Kondev, F.G.; Pfohl, J.; Riley, M.A.; Fischer, S.M.; Janssens, R.V.; Nisius, D.T.; Fallon, P.; Ma, W.C.; Simpson, J.

    1999-01-01

    High-spin states in the doubly-odd nuclei 154,156 Tb have been populated in two separate experiments using the 36 S+ 124 Sn reaction at different beam energies (160 and 175 MeV). The yrast structures of both nuclei were extended to much higher spin (I≤48ℎ) than previously known and several quasiparticle alignments have been identified. These include the second neutron alignment and a clear delineation of the second proton crossing in 156 Tb. Systematics of these crossings for odd-Z nuclei and comparisons with results of cranked shell model calculations are discussed. thinsp copyright 1999 The American Physical Society

  12. Treatment of active acne with an Er:Glass (1.54 microm) laser: a 2-year follow-up study.

    Science.gov (United States)

    Angel, Sylvie; Boineau, Dominique; Dahan, Serge; Mordon, Serge

    2006-12-01

    To investigate the effects of the 1.54 microm wavelength on active lesions of the face and of the back at the 2-year follow-up. A 1.54 microm erbium:glass laser (Aramis, Quantel Medical, France) was used in combination with contact cooling set at +5 degrees C to treat acne on the face with the following parameters (3 ms, four pulses, 10 J/cm2, 2 Hz, cumulative fluence: 40 J/cm2). The laser spots were adjacent (maximum overlap: 20%) and delivered in rows in order to cover the entire area. Four treatments were performed at 4-week intervals in 25 patients with acne severity greater than 3 on the Burton scale. Acne lesion counts (papules, pustules, nodules, comedones) were performed prior to each treatment, and at 2, 4, 12, 18 and 24 months after the final treatment. Among the 25 patients, three were lost to follow-up, four were retreated. So, 18 patients had acne lesions counts 2 years after the fourth treatment. The mean percent reduction was 71% at the 6-month follow-up, 79% at the 1-year follow-up and 73% at the 2-year follow-up. No side effects were reported. All patients commented that their skin was less prone to oiliness. Biopsies taken after treatment showed progressive rarefaction and miniaturization of sebaceous glands and pilosebaceous follicles without morphologic damage to epidermal and dermal structures. Active acne can be successfully treated by selective dermal heating with a 1.54 microm erbium:glass laser coupled to contact cooling, with no related side effects. Furthermore, this longer follow-up study demonstrates long-term acne clearing. Combined treatments with medications (oral or topical) or light (targeting Propionibacterium acnes) may also improve acne clearance.

  13. 75 FR 64947 - 154th Meeting of the Advisory Council on Employee Welfare and Pension Benefit Plans; Notice of...

    Science.gov (United States)

    2010-10-20

    ... Council on Employee Welfare and Pension Benefit Plans; Notice of Meeting; Notice #0;#0;Federal Register... Employee Benefits Security Administration 154th Meeting of the Advisory Council on Employee Welfare and... Advisory Council on Employee Welfare and Pension Benefit Plans will be held on November 3-4, 2010. The...

  14. Technical Note: A simulation study on the feasibility of radiotherapy dose enhancement with calcium tungstate and hafnium oxide nano- and microparticles.

    Science.gov (United States)

    Sherck, Nicholas J; Won, You-Yeon

    2017-12-01

    To assess the radiotherapy dose enhancement (RDE) potential of calcium tungstate (CaWO 4 ) and hafnium oxide (HfO 2 ) nano- and microparticles (NPs). A Monte Carlo simulation study was conducted to gauge their respective RDE potentials relative to that of the broadly studied gold (Au) NP. The study was warranted due to the promising clinical and preclinical studies involving both CaWO 4 and HfO 2 NPs as RDE agents in the treatment of various types of cancers. The study provides a baseline RDE to which future experimental RDE trends can be compared to. All three materials were investigated in silico with the software Penetration and Energy Loss of Positrons and Electrons (PENELOPE 2014) developed by Francesc Salvat and distributed in the United States by the Radiation Safety Information Computational Center (RSICC) at Oak Ridge National Laboratory. The work utilizes the extensively studied Au NP as the "gold standard" for a baseline. The key metric used in the evaluation of the materials was the local dose enhancement factor (DEF loc ). An additional metric used, termed the relative enhancement ratio (RER), evaluates material performance at the same mass concentrations. The results of the study indicate that Au has the strongest RDE potential using the DEF loc metric. HfO 2 and CaWO 4 both underperformed relative to Au with lower DEF loc of 2-3 × and 4-100 ×, respectively. The computational investigation predicts the RDE performance ranking to be: Au > HfO 2 > CaWO 4 . © 2017 American Association of Physicists in Medicine.

  15. Effect of Advanced Plasma Source bias voltage on properties of HfO2 films prepared by plasma ion assisted electron evaporation from metal hafnium

    International Nuclear Information System (INIS)

    Zhu, Meiping; Yi, Kui; Arhilger, Detlef; Qi, Hongji; Shao, Jianda

    2013-01-01

    HfO 2 films, using metal hafnium as starting material, are deposited by plasma-ion assisted electron evaporation with different Advanced Plasma Source (APS) bias voltages. The refractive index and extinction coefficient are calculated, the chemical state and composition, as well as the stress and aging behavior is investigated. Laser induced damage threshold (LIDT) and damage mechanism are also evaluated and discussed. Optical, structural, mechanical and laser induced damage properties of HfO 2 films are found to be sensitive to APS bias voltage. The film stress can be tuned by varying the APS bias voltage. Damage morphologies indicate the LIDT of the HfO 2 films at 1064 nm and 532 nm are dominated by the nodular-defect density in coatings, while the 355 nm LIDT is dominated by the film absorption. HfO 2 films with higher 1064 nm LIDT than samples evaporated from hafnia are achieved with bias voltage of 100 V. - Highlights: • HfO 2 films are evaporated with different Advanced Plasma Source (APS) bias voltages. • Properties of HfO 2 films are sensitive to APS bias voltage. • With a bias voltage of 100 V, HfO 2 coatings without any stress can be achieved. • Higher 1064 nm laser induced damage threshold is achieved at a bias voltage of 100 V

  16. 33 CFR 165.154 - Safety and Security Zones: Long Island Sound Marine Inspection Zone and Captain of the Port Zone.

    Science.gov (United States)

    2010-07-01

    ... 33 Navigation and Navigable Waters 2 2010-07-01 2010-07-01 false Safety and Security Zones: Long... Navigable Waters COAST GUARD, DEPARTMENT OF HOMELAND SECURITY (CONTINUED) PORTS AND WATERWAYS SAFETY... Areas First Coast Guard District § 165.154 Safety and Security Zones: Long Island Sound Marine...

  17. A Chemical, High-Temperature Way to Ag1.9Te via Quasi-Topotactic Reaction of Stuetzite-type Ag1.54Te: Structural and Thermoelectric Properties.

    Science.gov (United States)

    Baumer, Franziska; Nilges, Tom

    2017-11-20

    Semiconducting silver tellurides gained reasonable interest in the past years due to its thermoelectric, magneto-caloric, and nonlinear optic properties. Nanostructuring has been frequently used to address quantum-confinement effects of minerals and synthetic compounds in the Ag-Te system. Here, we report on the structural, thermal, and thermoelectric properties of stuetzite-like Ag 1.54 Te (or Ag 4.63 Te 3 ) and Ag 1.9 Te. By a quasi-topotactic reaction upon tellurium evaporation Ag 1.54 Te can be transferred to Ag 1.9 Te after heat treatment. Crystal structures, thermal and thermoelectric properties of stuetzite-like Ag 1.54 Te (or Ag 4.63 Te 3 ) and Ag 1.9 Te were determined by ex situ and in situ experiments. This method represents an elegant chemical way to Ag 1.9 Te, which was so far only accessible electrochemically via electrochemical removal of silver from the mineral hessite (Ag 2 Te). The mixed conductors show reasonable high total electric conductivities, very low thermal conductivities, and large Seebeck coefficients, which result in a significant high thermoelectric figure of 0.57 at 680 K.

  18. Identification of seven haplotypes of the caprine PrP gene at codons 127, 142, 154, 211, 222 and 240 in French Alpine and Saanen breeds and their association with classical scrapie.

    Science.gov (United States)

    Barillet, F; Mariat, D; Amigues, Y; Faugeras, R; Caillat, H; Moazami-Goudarzi, K; Rupp, R; Babilliot, J M; Lacroux, C; Lugan, S; Schelcher, F; Chartier, C; Corbière, F; Andréoletti, O; Perrin-Chauvineau, C

    2009-03-01

    In sheep, susceptibility to scrapie is mainly influenced by polymorphisms of the PrP gene. In goats, there are to date few data related to scrapie susceptibility association with PrP gene polymorphisms. In this study, we first investigated PrP gene polymorphisms of the French Alpine and Saanen breeds. Based on PrP gene open reading frame sequencing of artificial insemination bucks (n=404), six encoding mutations were identified at codons 127, 142, 154, 211, 222 and 240. However, only seven haplotypes could be detected: four (GIH(154)RQS, GIRQ(211)QS, GIRRK(222)S and GIRRQP(240)) derived from the wild-type allele (G(127)I(142)R(154)R(211)Q(222)S(240)) by a single-codon mutation, and two (S(127)IRRQP(240) and GM(142)RRQP(240)) by a double-codon mutation. A case-control study was then implemented in a highly affected Alpine and Saanen breed herd (90 cases/164 controls). Mutations at codon 142 (I/M), 154 (R/H), 211 (R/Q) and 222 (Q/K) were found to induce a significant degree of protection towards natural scrapie infection. Compared with the baseline homozygote wild-type genotype I(142)R(154)R(211)Q(222)/IRRQ goats, the odds of scrapie cases in IRQ(211)Q/IRRQ and IRRK(222)/IRRQ heterozygous animals were significantly lower [odds ratio (OR)=0.133, PFrench Alpine and Saanen breeds were low (0.5-18.5 %), which prevent us from assessing the influence of all the possible genotypes in natural exposure conditions.

  19. Study of the structure of the transition nuclei 152Dy, 154Dy and 156Er at high angular momentum

    International Nuclear Information System (INIS)

    Azgui, F.

    1985-01-01

    Measurements of feeding times of high spin yrast states in 152 Dy, 154 Dy and 156 Er were utilized to obtain information about possible spin dependent shape changes. Feeding times as well as lifetimes were determined with the recoil distance technique. In 152 Dy only long feeding times (> 10 ps) could be identified, indicating that the aligned-particle yrast states are fed through configuration of similar character, with little direct population from collective cascade in the continuum region. In 154 Dy discrete states with I ≤ 30 have lifetimes which are characteristically collective, whereas the preyrast cascade exhibit both fast ( 10 ps) feeding components. The latter imply a change with increasing spin from collective to aligned-particle character, signalling a prolate to oblate shape transition. In 156 Er the yrast states up to spin 20 ℎ were found to be collective. These levels are fed, however, from long-lived high spin states, causing time delay up to ∼ 100 ps, the existence of which is interpreted as a signature for an oblate shape at high spin [fr

  20. New isomeric states in 152,154,156Nd produced by spontaneous fission of 252Cf

    International Nuclear Information System (INIS)

    Gautherin, C.; Houry, M.; Korten, W.; Le Coz, Y.; Lucas, R.; Phan, X.H.; Theisen, C.; Belier, G.; Girod, M.; Meot, V.; Peru, S.; Astier, A.; Ducroux, L.; Meyer, M.; Redon, N.

    1998-01-01

    Isomeric states have been observed in fission-fragments produced by spontaneous fission of 252 Cf. These states are found in neutron rich nuclei of different structure and deformations. About 50 isomeric nuclei have been observed using coincidences between γ-rays identified in EUROGAM II and fission fragments detected in photovoltaic cells (SAPhIR). Lifetimes in the range from 20 ns to 2μs have been measured. Presented calculations based on HFB+D1S force on new measured isomeric states in the 152,154,156 Nd show evidence for K-isomers. (orig.)

  1. Impedance Characterization of the Capacitive field-Effect pH-Sensor Based on a thin-Layer Hafnium Oxide Formed by Atomic Layer Deposition

    Directory of Open Access Journals (Sweden)

    Michael LEE

    2014-05-01

    Full Text Available As a sensing element, silicon dioxide (SiO2 has been applied within ion-sensitive field effect transistors (ISFET. However, a requirement of increasing pH-sensitivity and stability has observed an increased number of insulating materials that obtain high-k gate being applied as FETs. The increased high-k gate reduces the required metal oxide layer and, thus, the fabrication of thin hafnium oxide (HfO2 layers by atomic layer deposition (ALD has grown with interest in recent years. This metal oxide presents advantageous characteristics that can be beneficial for the advancements within miniaturization of complementary metal oxide semiconductor (CMOS technology. In this article, we describe a process for fabrication of HfO2 based on ALD by applying water (H2O as the oxygen precursor. As a first, electrochemical impedance spectroscopy (EIS measurements were performed with varying pH (2-10 to demonstrate the sensitivity of HfO2 as a potential pH sensing material. The Nyquist plot demonstrates a high clear shift of the polarization resistance (Rp between pH 6-10 (R2 = 0.9986, Y = 3,054X + 12,100. At acidic conditions (between pH 2-10, the Rp change was small due to the unmodified oxide gate (R2 = 0.9655, Y = 2,104X + 4,250. These preliminary results demonstrate the HfO2 substrate functioned within basic to neutral conditions and establishes a great potential for applying HfO2 as a dielectric material for future pH measuring FET sensors.

  2. A silicon doped hafnium oxide ferroelectric p–n–p–n SOI tunneling field–effect transistor with steep subthreshold slope and high switching state current ratio

    Directory of Open Access Journals (Sweden)

    Saeid Marjani

    2016-09-01

    Full Text Available In this paper, a silicon–on–insulator (SOI p–n–p–n tunneling field–effect transistor (TFET with a silicon doped hafnium oxide (Si:HfO2 ferroelectric gate stack is proposed and investigated via 2D device simulation with a calibrated nonlocal band–to–band tunneling model. Utilization of Si:HfO2 instead of conventional perovskite ferroelectrics such as lead zirconium titanate (PbZrTiO3 and strontium bismuth tantalate (SrBi2Ta2O9 provides compatibility to the CMOS process as well as improved device scalability. By using Si:HfO2 ferroelectric gate stack, the applied gate voltage is effectively amplified that causes increased electric field at the tunneling junction and reduced tunneling barrier width. Compared with the conventional p–n–p–n SOI TFET, the on–state current and switching state current ratio are appreciably increased; and the average subthreshold slope (SS is effectively reduced. The simulation results of Si:HfO2 ferroelectric p–n–p–n SOI TFET show significant improvement in transconductance (∼9.8X enhancement at high overdrive voltage and average subthreshold slope (∼35% enhancement over nine decades of drain current at room temperature, indicating that this device is a promising candidate to strengthen the performance of p–n–p–n and conventional TFET for a switching performance.

  3. 1.54 μm Er3+ electroluminescence from an erbium-compound-doped organic light emitting diode with a p-type silicon anode

    International Nuclear Information System (INIS)

    Zhao, W Q; Wang, P F; Ran, G Z; Ma, G L; Zhang, B R; Liu, W M; Wu, S K; Dai, L; Qin, G G

    2006-01-01

    By doping an erbium complex, erbium (III) 2, 4-pentanedionate (Er(acac) 3 ), into the ALQ layer, we fabricate a series of infrared emission organic light emitting diodes (OLED) with structures of p-Si/SiO 2 /NPB/ALQ/ ALQ:Er(acac) 3 /ALQ/Sm/Au, where p-Si is the anode and Sm/Au is the cathode. The 1.54 μm emission from Er 3+ is observed. The impact of doping level of Er(acac) 3 in ALQ on 1.54 μm electroluminescence (EL) intensity is studied, and the best mass ratio of Er(acac) 3 to ALQ is found at 1:60. A competitive EL mechanism from the ALQ and Er(acac) 3 is found and the Er 3+ ions excitations are attributed to energy transfer from the ligands to Er ions

  4. Synergistic effect of carbon nanotube as sintering aid and toughening agent in spark plasma sintered molybdenum disilicide-hafnium carbide composite

    Energy Technology Data Exchange (ETDEWEB)

    Mukherjee, Biswajyoti; Asiq Rahman, O.S.; Sribalaji, M [Materials Science and Engineering, Indian Institute of Technology Patna, Bihta Kanpa Road, Bihta, Patna, Bihar 801103 (India); Bakshi, Srinivasa Rao [Department of Metallurgical and Materials Engineering, Indian Institute of Technology Madras, Chennai 600036 (India); Keshri, Anup Kumar, E-mail: anup@iitp.ac.in [Materials Science and Engineering, Indian Institute of Technology Patna, Bihta Kanpa Road, Bihta, Patna, Bihar 801103 (India)

    2016-12-15

    Hafnium carbide (HfC) along with sintering aids was consolidated at a relatively lower temperature i.e. 1600 °C (i.e. T=~0.41 T{sub m}) under a uniaxial load of 50 MPa by spark plasma sintering. Two different sintering aids such as molybdenum disilicide (MoSi{sub 2}) and carbon nanotube (CNT) were added to enhance the densification and lower the extent of grain growth in the sintered pellets. Density of the sintered pellet increased from 96.0±0.8% in HfC +5 wt% MoSi{sub 2} (HM) to 99.0±0.5% with the addition of 2 wt% CNT in HfC+5 wt% MoSi{sub 2} (HMC) at sintering temperature of 1600 °C. Further, the extent of grain growth drastically reduced from 204% in HM to 50% in HMC. Analysis of linear shrinkage during densification revealed that CNT addition increased densification rate and decreased the time required to reach the density of 99.0±0.5% at 1600 °C. Increased densification and lower degree of grain growth could be due to the synergistic effect offered by the CNT, which are as follows: (i) Lubrication effect of CNT, (ii) Lower activation energy for grain boundary diffusion (iii) Reduction in liquid phase sintering temperature and (iv) Grain boundary pinning. Fracture toughness of the sintered HM and HMC composite was obtained using indentation technique. By the addition of 2 wt% CNT in HM, drastic increase of 91% in fracture toughness was seen. This significant improvement in fracture toughness was due to the enhanced densification and relatively lower grain size of HMC. Also crack bridging, crack deflection, crack arrest, CNT and graphene sheet pull-out and swording played major role in toughening of HMC pellet.

  5. X-ray tube targets

    International Nuclear Information System (INIS)

    Hirsch, H.H.

    1980-01-01

    In rotary targets for X-ray tubes warping is a problem which causes X-ray deficiency. A rotary target is described in which warping is reduced by using alloys of molybdenum with 0.05 to 10% iron, silicon, cobalt, tantalum, niobium, hafnium, stable metal oxide or mixture thereof. Suitable mixtures are 0.5 to 10% of tantalum, niobium or hafnium with from 0.5 to 5% yttrium oxide, or 0.05 to 0.3% of cobalt or silicon. Optionally 0.1 to 5% by weight of additional material may be alloyed with the molybdenum, such as tantalum or hafnium carbides. (author)

  6. 40 CFR 421.332 - Effluent limitations guidelines representing the degree of effluent reduction attainable by the...

    Science.gov (United States)

    2010-07-01

    ... times. (d) SiCl4 purification wet air pollution control. BPT Limitations for the Primary Zirconium and...) Sand drying wet air pollution control. BPT Limitations for the Primary Zirconium and Hafnium... chlorination off-gas wet air pollution control. BPT Limitations for the Primary Zirconium and Hafnium...

  7. The type 2 diabetes risk allele of TMEM154-rs6813195 associates with decreased beta cell function in a study of 6,486 Danes.

    Directory of Open Access Journals (Sweden)

    Marie Neergaard Harder

    Full Text Available A trans-ethnic meta-analysis of type 2 diabetes genome-wide association studies has identified seven novel susceptibility variants in or near TMEM154, SSR1/RREB1, FAF1, POU5F1/TCF19, LPP, ARL15 and ABCB9/MPHOSPH9. The aim of our study was to investigate associations between these novel risk variants and type 2 diabetes and pre-diabetic traits in a Danish population-based study with measurements of plasma glucose and serum insulin after an oral glucose tolerance test in order to elaborate on the physiological impact of the variants.Case-control analyses were performed in up to 5,777 patients with type 2 diabetes and 7,956 individuals with normal fasting glucose levels. Quantitative trait analyses were performed in up to 5,744 Inter99 participants naïve to glucose-lowering medication. Significant associations between TMEM154-rs6813195 and the beta cell measures insulinogenic index and disposition index and between FAF1-rs17106184 and 2-hour serum insulin levels were selected for further investigation in additional Danish studies and results were combined in meta-analyses including up to 6,486 Danes.We confirmed associations with type 2 diabetes for five of the seven SNPs (TMEM154-rs6813195, FAF1-rs17106184, POU5F1/TCF19-rs3130501, ARL15-rs702634 and ABCB9/MPHOSPH9-rs4275659. The type 2 diabetes risk C-allele of TMEM154-rs6813195 associated with decreased disposition index (n=5,181, β=-0.042, p=0.012 and insulinogenic index (n=5,181, β=-0.032, p=0.043 in Inter99 and these associations remained significant in meta-analyses including four additional Danish studies (disposition index n=6,486, β=-0.042, p=0.0044; and insulinogenic index n=6,486, β=-0.037, p=0.0094. The type 2 diabetes risk G-allele of FAF1-rs17106184 associated with increased levels of 2-hour serum insulin (n=5,547, β=0.055, p=0.017 in Inter99 and also when combining effects with three additional Danish studies (n=6,260, β=0.062, p=0.0040.Studies of type 2 diabetes intermediary

  8. Electrochemical-metallothermic reduction of zirconium in molten salt solutions

    International Nuclear Information System (INIS)

    McLaughlin, D.F.; Talko, F.

    1990-01-01

    This patent describes a method for separating hafnium from zirconium of the type wherein a feed containing zirconium and hafnium chlorides is prepared from zirconium-hafnium chloride and the feed is introduced into a distillation column, which distillation column has a reboiler connected at the bottom and a reflux condenser connected at the top and wherein a hafnium chloride enriched stream is taken from the top of the column and a zirconium enriched chloride stream is taken from the bottom of the column. It comprises: reducing the zirconium enriched chloride stream taken from the distillation column to metal by electrochemically reducing an alkaline earth metal in a molten salt bath with the molten salt in the molten salt bath consisting essentially of a mixture of at least one alkali metal chloride and at least one alkaline earth metal chloride and zirconium chloride, with the reduced alkaline earth metal reacting with the zirconium chloride to produce zirconium metal and alkaline earth metal chloride

  9. Spectroscopic and structural investigation of undoped and Er{sup 3+} doped hafnium silicate layers

    Energy Technology Data Exchange (ETDEWEB)

    Khomenkova, L., E-mail: khomen@ukr.net [CIMAP CEA/CNRS/ENSICAEN/UCBN, 6 Blvd. Maréchal Juin, 14050 Caen Cedex 4 (France); V. Lashkaryov Institute of Semiconductor Physics at NASU, 41 Pr. Nauky, Kyiv 03028 (Ukraine); An, Y.-T. [CIMAP CEA/CNRS/ENSICAEN/UCBN, 6 Blvd. Maréchal Juin, 14050 Caen Cedex 4 (France); Khomenkov, D. [Taras Shevchenko National University of Kyiv, Faculty of Physics, 4 Pr. Hlushkov, Kyiv 03022 (Ukraine); Portier, X.; Labbé, C.; Gourbilleau, F. [CIMAP CEA/CNRS/ENSICAEN/UCBN, 6 Blvd. Maréchal Juin, 14050 Caen Cedex 4 (France)

    2014-11-15

    This paper demonstrates the functionality of radio-frequency magnetron sputtering for the fabrication of undoped and Er-doped Si-rich-HfO{sub 2} films with specific structural and spectroscopic properties. The effect of post-deposition treatment on film properties was investigated by means of Fourier-transform infrared spectroscopy, Raman scattering and photoluminescence methods, as well as Transmission Electron microscopy. It was observed that annealing treatment at 850–1000 °C causes phase separation process and the formation of HfO{sub 2}, SiO{sub 2} and pure Si phases. This process stimulates also an intense light emission in the 700–950-nm spectral range under broad band excitation. The phase separation mechanism as well as the nature of radiative transitions were discussed. Photoluminescence was ascribed to carrier recombination in silicon clusters and host defects. The appearance of silicon clusters was also confirmed by the comparison of luminescent properties of pure HfO{sub 2}, SiO{sub 2}, Si-rich-HfO{sub 2} and Si-rich-SiO{sub 2} films. Additional argument for Si clusters’ formation was obtained under investigation of Er-doped Si-rich HfO{sub 2} films. These latter demonstrated 1.54-µm Er{sup 3+} luminescence under non-resonant excitation originating from an energy transfer from Si clusters towards Er{sup 3+} ions.

  10. New neutron-rich isotope production in 154Sm+160Gd

    Directory of Open Access Journals (Sweden)

    Ning Wang

    2016-09-01

    Full Text Available Deep inelastic scattering in 154Sm+160Gd at energies above the Bass barrier is for the first time investigated with two different microscopic dynamics approaches: improved quantum molecular dynamics (ImQMD model and time dependent Hartree–Fock (TDHF theory. No fusion is observed from both models. The capture pocket disappears for this reaction due to strong Coulomb repulsion and the contact time of the di-nuclear system formed in head-on collisions is about 700 fm/c at an incident energy of 440 MeV. The isotope distribution of fragments in the deep inelastic scattering process is predicted with the simulations of the latest ImQMD-v2.2 model together with a statistical code (GEMINI for describing the secondary decay of fragments. More than 40 extremely neutron-rich unmeasured nuclei with 58≤Z≤76 are observed and the production cross sections are at the order of μb to mb. The multi-nucleon transfer reaction of Sm+Gd could be an alternative way to synthesize new neutron-rich lanthanides which are difficult to be produced with traditional fusion reactions or fission of actinides.

  11. Hepatic in vitro toxicity assessment of PBDE congeners BDE47, BDE153 and BDE154 in Atlantic salmon (Salmo salar L.)

    Energy Technology Data Exchange (ETDEWEB)

    Softeland, Liv, E-mail: lso@nifes.no [National Institute of Nutrition and Seafood Research, PO Box 2029 Nordnes, N-5817 Bergen (Norway); Petersen, Kjell [Computational Biology Unit, Bergen Centre for Computational Science, Uni Research AS, Thormohlensgt 55, N5008 Bergen (Norway); Stavrum, Anne-Kristin [Dept of Clinical Medicine, University of Bergen (Norway); Wu, Terence [Yale University W.M. Keck Biotechnology Resource, 300 George St., Room G001, New Haven, CT 06511 (United States); Olsvik, Pal A. [National Institute of Nutrition and Seafood Research, PO Box 2029 Nordnes, N-5817 Bergen (Norway)

    2011-10-15

    The brominated flame retardant congeners BDE47, BDE153 and BDE154 are among the congeners accumulating to the highest degree in fish. In order to gain knowledge about the toxicological effects of PBDEs in fish, microarray-based transcriptomic and 2D-DIGE/MALDI-TOF/TOF proteomic approaches were used to screen for effects in primary Atlantic salmon hepatocytes exposed to these congeners alone or in combination (PBDE-MIX). A small set of stress related transcripts and proteins were differentially expressed in the PBDE exposed hepatocytes. The PBDE-MIX, and BDE153 to a lesser degree, seems to have induced metabolic disturbances by affecting several pathways related to glucose homeostasis. Further, effects on cell cycle control and proliferation signal pathways in PBDE-MIX-exposed hepatocytes clearly suggest that the PBDE exposure affected cell proliferation processes. CYP1A was 7.41- and 7.37-fold up-regulated in hepatocytes exposed to BDE47 and PBDE-MIX, respectively, and was the only biotransformation pathway affected by the PBDE exposure. The factorial design and PLS regression analyses of the effect of the PBDE-MIX indicated that BDE47 contributed the most to the observed CYP1A response, suggesting that this congener should be incorporated in the toxic equivalent (TEQ) concept in future risk assessment of dioxin-like chemicals. Additionally, a significant up-regulation of the ER-responsive genes VTG and ZP3 was observed in cells exposed to BDE47 and PBDE-MIX. Further analyses suggested that BDE47 and BDE154 have an estrogenic effect in male fish. The data also suggested an antagonistic interaction between BDE153 and BDE154. In conclusion, this study shows that PBDEs can affect several biological systems in Atlantic salmon cells, and demonstrates the need for more studies on the simultaneous exposure to chemical mixtures to identify combined effects of chemicals.

  12. Determination of hafnium at the 10−4% level (relative to zirconium content) using neutron activation analysis, inductively coupled plasma mass spectrometry and inductively coupled plasma atomic emission spectrometry

    International Nuclear Information System (INIS)

    Smolik, Marek; Polkowska-Motrenko, Halina; Hubicki, Zbigniew; Jakóbik-Kolon, Agata; Danko, Bożena

    2014-01-01

    Graphical abstract: -- Highlights: •We worked out ICP-MS method of Hf determination in Zr and Zr compounds. •We used NAA method as reference one. •We obtained pure zirconium matrix by ion exchange (Diphonix ® resin). •These permit to determine ≥1 × 10 −4 % Hf in Zr sample by ICP MS with good precision and accuracy. -- Abstract: Hafnium at the very low level of 1–8 ppm (in relation to zirconium) was determined in zirconium sulfate solutions (originating from investigations of the separation of ca. 44 ppm Hf from zirconium by means of the ion exchange method) by using three independent methods: inductively coupled plasma mass spectrometry (ICP MS), neutron activation analysis (NAA) and inductively coupled plasma atomic emission spectrometry (ICP-AES). The results of NAA and ICP MS determinations were consistent with each other across the entire investigated range (the RSD of both methods did not exceed 38%). The results of ICP-AES determination were more diverse, particularly at less than 5 ppm Hf (RSD was significantly higher: 29–253%). The ion exchange method exploiting Diphonix ® resin proved sufficient efficiency in Zr–Hf separation when the initial concentration ratio of the elements ([Zr] 0 /[Hf] 0 ) ranged from 1200 to ca. 143,000

  13. Perturbed angular correlation

    International Nuclear Information System (INIS)

    Fabris, J.D.

    1977-01-01

    The electric quadrupolar interaction in some hafnium complexes, measured at the metal nucleus level is studied. For that purpose, the technique of γ-γ perturbed angular correlation is used: the frequencies of quadrupolar interaction are compared with some hafnium α-hydroxicarboxilates, namely glycolate, lactate, mandelate and benzylate; the influence of the temperature on the quadrupolar coupling on the hafnium tetramandelate is studied; finally, the effects associated with the capture of thermal neutrons by hafnium tetramandelate are examined locally at the nuclear level. The first group of results shows significant differences in a series of complexes derived from glycolic acid. On the other hand, the substitution of the protons in hafnium tetramandelate structure by some alkaline cations permits to verify a correlation between the variations in the quadrupolar coupling and the electronegativities of the substituent elements. Measurements at high temperatures show that this complex is thermally stable at 100 and 150 0 C. It is possible to see the appearance of two distinct sites for the probe nucleus, after heating the sample at 100 0 C for prolonged time. This fact is attributed to a probable interconversion among the postulated structural isomers for the octacoordinated compounds. Finally, measurements of angular correlation on the irradiated complex show that there is an effective destruction of the target molecule by neutron capture [pt

  14. Efficient 1.54-μm emission through Eu2+ sensitization of Er3+ in thin films of Eu2+/Er3+ codoped barium strontium silicate under broad ultraviolet light excitation

    International Nuclear Information System (INIS)

    Li, Leliang; Zheng, Jun; Zuo, Yuhua; Cheng, Buwen; Wang, Qiming

    2015-01-01

    Thin films of Eu 2+ /Er 3+ codoped barium strontium silicate were deposited on a thermal oxide Si substrate by magnetron sputtering. Optical properties suggest that after a rapid annealing process, these films can lead to efficient Er 3+ emission at 1.54 μm with a lifetime of about 7.9 ms. Intense 1.54-μm light emission was achieved under broad ultraviolet light excitation through efficient energy transfer from Eu 2+ to Er 3+ . These results indicate that the Eu 2+ /Er 3+ thin films have potential applications as low cost and compact erbium doped waveguide amplifiers pumped by LEDs. - Highlights: • The Er 0.07 Eu 0.14 Sr 1.14 Ba 0.79 SiO 4 films are fabricated by magnetron sputtering. • Efficient energy transfer from Eu 2+ to Er 3+ ions by the dipole–dipole interaction. • Intense 1.54 μm emission is achieved under broad excitation spectrum. • The films have potential applications as low cost and compact EDWAs

  15. Photochemical studies of alkylammonium molybdates. Part 12. O→Mo charge-transfer triplet-states-initiated self-assembly to {Mo154} ring- and tube-molybdenum-blues

    Science.gov (United States)

    Yamase, T.; Prokop, P.; Arai, Y.

    2003-08-01

    The chemically induced dynamic electron-spin-polarization technique is employed in order to investigate the primary steps of the photoredox reaction between polyoxomolybdates and alkylammonium cations as both proton and electron-donors in solutions. An observation of emissive electron-spin-polarization signals of alkylamino radical cations for the photoredox reaction between polyoxomolybdates and alkylammonium cations in solutions reveals that the O→Mo ligand-to-metal charge-transfer triplet states are involved in the transfers of both proton and electron from alkylammonium cation to polyoxomolybdate anions. Prolonged photolysis of aqueous solutions containing [Mo36O112(H2O)16]8-, [iPrNH3]+, and LaCl3 at pH 1.0 leads to formation of two kinds of {Mo154} molybdenum-blues, [Mo28VMo126VIO462H28(H2O)70]·156.5H2O (1) and [iPrNH3]8 [Mo28VMo126VIO458H12(H2O)66]·127H2O (2), which were X-ray crystallographically characterized. The former exhibits the intact car-tire-shaped {Mo154} ring structure (with thickness of about 1.1 nm and with outer- and inner-rings of approximately 3.5- and 2.3-nm diameters, respectively) derived formally from the dehydrated cyclic heptamerization of four-electron reduced building blocks of {Mo22} (≡[Mo4VMo18VIO70H12(H2O)10]) with overall symmetry of D7d. The anion for the latter, [Mo28VMo126VIO458H12(H2O)66]8- (2a), exhibits a nanotube structure of {Mo154} rings, each inner ring of which contains a bis(μ-oxo)-linkaged [MoO2(μ-O)(μ-H2O)MoO2]2+ unit replacing one of seven [Mo(H2O)O2(μ-O)Mo(H2O)O2]2+linker units. The neighboring {Mo154} rings are connected by six Mo-O-Mo bridge between inner-rings consisting of 7 head- and 14 linkers-MoO6 octahedra for each.

  16. Use of the on-line Moessbauer effect as a contribution to the study of recoil defects in solids

    International Nuclear Information System (INIS)

    Jeandey, Christian

    1974-01-01

    This research thesis addresses the study of effects of nuclear reactions, also known as 'after-effects' such as atomic disorders resulted from atom recoil, but also possible chemical modifications. The author more particularly focuses of recoil defects. He reports a critical review of studies of structure defects (in pure metals, ordered alloys, ionic crystals) performed by using conventional resonance absorption, and then presents an analysis of results of the defect creation dynamics as it had been proposed by other authors. He also proposes an overview of the evolution and disappearance of defects during thermal treatments. After a review of experiments based on the on-line Moessbauer effect, the author reports the study of recoil effects in pure metals (iron, hafnium), in alloys (Fe 1-x Al x , FeGe 2 , cubic, monoclinic and hexagonal FeGe), and in organic complexes (ferrous oxalate, different types of hafnium chelate, hafnium oxide). He finally discusses the electronic properties of different types of iron and hafnium chelate in solid phase [fr

  17. Grindability of cast Ti-Hf alloys.

    Science.gov (United States)

    Kikuchi, Masafumi; Takahashi, Masatoshi; Sato, Hideki; Okuno, Osamu; Nunn, Martha E; Okabe, Toru

    2006-04-01

    As part of our systematic studies characterizing the properties of titanium alloys, we investigated the grindability of a series of cast Ti-Hf alloys. Alloy buttons with hafnium concentrations up to 40 mass% were made using an argon-arc melting furnace. Each button was cast into a magnesia-based mold using a dental titanium casting machine; three specimens were made for each metal. Prior to testing, the hardened surface layer was removed. The specimens were ground at five different speeds for 1 min at 0.98 N using a carborundum wheel on an electric dental handpiece. Grindability was evaluated as the volume of metal removed per minute (grinding rate) and the volume ratio of metal removed compared to the wheel material lost (grinding ratio). The data were analyzed using ANOVA. A trend of increasing grindability was found with increasing amounts of hafnium, although there was no statistical difference in the grindability with increasing hafnium contents. We also found that hafnium may be used to harden or strengthen titanium without deteriorating the grindability.

  18. AGR-2 Final Data Qualification Report for U.S. Capsules - ATR Cycles 147A Through 154B

    Energy Technology Data Exchange (ETDEWEB)

    Pham, Binh T. [Idaho National Lab. (INL), Idaho Falls, ID (United States). Very High-Temperature Reactor Technology Development Office; Einerson, Jeffrey J. [Idaho National Lab. (INL), Idaho Falls, ID (United States). Very High-Temperature Reactor Technology Development Office

    2014-07-01

    This report provides the data qualification status of AGR-2 fuel irradiation experimental data in four U.S. capsules from all 15 Advanced Test Reactor (ATR) Cycles 147A, 148A, 148B, 149A, 149B, 150A, 150B, 151A, 151B, 152A, 152B, 153A, 153B, 154A, and 154B, as recorded in the Nuclear Data Management and Analysis System (NDMAS). Thus, this report covers data qualification status for the entire AGR-2 irradiation and will replace four previously issued AGR-2 data qualification reports (e.g., INL/EXT-11-22798, INL/EXT-12-26184, INL/EXT-13-29701, and INL/EXT-13-30750). During AGR-2 irradiation, two cycles, 152A and 153A, occurred when the ATR core was briefly at low power, so AGR-2 irradiation data are not used for physics and thermal calculations. Also, two cycles, 150A and 153B, are Power Axial Locator Mechanism (PALM) cycles when the ATR power is higher than during normal cycles. During the first PALM cycle, 150A, the experiment was temporarily moved from the B-12 location to the ATR water canal and during the second PALM cycle, 153B, the experiment was temporarily moved from the B-12 location to the I-24 location to avoid being overheated. During the “Outage” cycle, 153A, seven flow meters were installed downstream from seven Fission Product Monitoring System (FPMS) monitors to measure flows from the monitors and these data are included in the NDMAS database.

  19. New isomeric states in {sup 152,154,156}Nd produced by spontaneous fission of {sup 252}Cf

    Energy Technology Data Exchange (ETDEWEB)

    Gautherin, C.; Houry, M.; Korten, W.; Le Coz, Y.; Lucas, R.; Phan, X.H.; Theisen, C. [Commissariat l`Energie Atomique de Saclay, Gif sur Yvette (France). DSM/DAPINA/SPhN; Badimon, C.; Barreau, G.; Doan, T.P.; Pedemay, G. [Centre d`Etudes Nucleaires de Bordeaux-Gradignan, Domaine du Haut Vigneau, F-33175 Gradignan (France); Belier, G.; Girod, M.; Meot, V.; Peru, S. [Commissariat a l`Energie Atomique de Bruyeres-le-Chatel, DAM/SPN, BP12, F-91680 Bruyeres-le-Chatel (France); Astier, A.; Ducroux, L.; Meyer, M.; Redon, N. [Institut de Physique Nucleaire de Lyon, F-69622 Villeurbanne Cedex (France)

    1998-04-01

    Isomeric states have been observed in fission-fragments produced by spontaneous fission of {sup 252}Cf. These states are found in neutron rich nuclei of different structure and deformations. About 50 isomeric nuclei have been observed using coincidences between {gamma}-rays identified in EUROGAM II and fission fragments detected in photovoltaic cells (SAPhIR). Lifetimes in the range from 20 ns to 2{mu}s have been measured. Presented calculations based on HFB+D1S force on new measured isomeric states in the {sup 152,154,156}Nd show evidence for K-isomers. (orig.) With 8 figs., 27 refs.

  20. Radioisotopic heat source

    Science.gov (United States)

    Jones, G.J.; Selle, J.E.; Teaney, P.E.

    1975-09-30

    Disclosed is a radioisotopic heat source and method for a long life electrical generator. The source includes plutonium dioxide shards and yttrium or hafnium in a container of tantalum-tungsten-hafnium alloy, all being in a nickel alloy outer container, and subjected to heat treatment of from about 1570$sup 0$F to about 1720$sup 0$F for about one h. (auth)

  1. High-spin nuclear target of 178m2Hf: creation and nuclear reaction studies

    International Nuclear Information System (INIS)

    Oganessyan, Yu.Ts.; Karamyan, S.A.; Gangrskij, Yu.P.

    1993-01-01

    A long-lived (31 years) four-quasiparticle isomer 178m 2 Hf(I,K π =16,16 + ) was produced in microweight quantities using the nuclear reaction 176 Yb( 4 He, 2n). Methods of precision chemistry and mass-separation for the purification of the produced Hf material have been developed. Thin targets of isomeric hafnium-178 on carbon backings were prepared and used in experiments on a neutron, proton and deuteron beams. First results on nuclear reactions on a high-spin exotic target were obtained. Experiments on electromagnetic interactions of the isomeric hafnium using methods of the collinear laser spectroscopy as well as of the nuclear orientation of hafnium implanted into a crystalline media were started. 11 refs.; 11 figs.; 2 tabs

  2. New type of colour reactions of o,o'-dihydroxyazo compounds

    International Nuclear Information System (INIS)

    Dedkov, Yu.M.; Podvigina, T.I.

    1977-01-01

    It is shown that in the system: zirconium (hafnium)-picramine-epsilon (PE)-ethylrhodamine S (ERS), a heteroligand complex is formed, with an excess of the organic reagents, having the following ratio of components: Zr(Hf):PE:ERS=1:2:5. The molecules of ERS substitute the protons of free OH groups in binary complexes of zirconium (hafnium) with PE, while the excess molecules of ERS are added associatively. The resulting complex is floated off, the flotation product is dissolved in acetone, and its optical density is measured. The true molar extinction coefficient of the complex is equal to 6x10 5 , while the apparent one equals 3.2x10 5 . It is possible to determine submicroamounts of zirconium (hafnium) with preminary Ti and Nb masking

  3. Evolution of E 2 transition strength in deformed hafnium isotopes from new measurements on 172Hf,174Hf, and 176Hf

    Science.gov (United States)

    Rudigier, M.; Nomura, K.; Dannhoff, M.; Gerst, R.-B.; Jolie, J.; Saed-Samii, N.; Stegemann, S.; Régis, J.-M.; Robledo, L. M.; Rodríguez-Guzmán, R.; Blazhev, A.; Fransen, Ch.; Warr, N.; Zell, K. O.

    2015-04-01

    Background: The available data for E 2 transition strengths in the region between neutron-deficient hafnium and platinum isotopes are far from complete. More and precise data are needed to enhance the picture of structure evolution in this region and to test state-of-the-art nuclear models. In a simple model, the maximum collectivity is expected at the middle of the major shell. However, for actual nuclei, particularly in heavy-mass regions, which should be highly complex, this picture may no longer be the case, and one should use a more realistic nuclear-structure model. We address this point by studying the spectroscopy of Hf as a representative case. Purpose: We remeasure the 21+ half-lives of 172,174,176Hf, for which there is some disagreement in the literature. The main goal is to measure, for the first time, the half-lives of higher-lying states of the rotational band. The new results are compared to a theoretical calculation for absolute transition strengths. Method: The half-lives were measured using γ -γ and conversion-electron-γ delayed coincidences with the fast timing method. For the determination of half-lives in the picosecond region, the generalized centroid difference method was applied. For the theoretical calculation of the spectroscopic properties, the interacting boson model is employed, whose Hamiltonian is determined based on microscopic energy-density functional calculations. Results: The measured 21+ half-lives disagree with results from earlier γ -γ fast timing measurements, but are in agreement with data from Coulomb excitation experiments and other methods. Half-lives of the 41+ and 61+ states were measured, as well as a lower limit for the 81+ states. Conclusions: This work shows the importance of a mass-dependent effective boson charge in the interacting boson model for the description of E 2 transition rates in chains of nuclei. It encourages further studies of the microscopic origin of this mass dependence. New experimental

  4. Improving the Transmission System Reliability for the 154kV Radial Network Operation

    Energy Technology Data Exchange (ETDEWEB)

    Choo, Jin Boo; Yoo, Myeong Ho; Yoon, Young Beum; Kim, Tae Won [Korea Electric Power Research Institute, Taejon (Korea, Republic of); Lee, Gi Won; Chung, Beom Jin; Jung, Jung Won; Park, Kyu Hyun; Lee, Myung Hee; Kim, Hyun Jong; Kim, Chae Hee [KEYIN CO., (Korea, Republic of)

    1996-12-31

    Analyzing that 154kV radial network current ed operated, we developed Automatic Power Reconfiguration System(APRS) which restore blackout area. It consists of special data acquisition system(DAU) and central monitoring system for reason of protecting currently operating power system. In addition, it communicates using optical communication network for high speed data transmission and accuracy. An Accuracy of operation and stability of the developed system is tested using Real Time Digital Simulator in 3-bus equivalent model system. In An Outage case, our developed system can restore a blackout area in three second. An ability of the restoration of a blackout was verified by simulations. For the field test, the developed system was set up at SINCHON S/S, SESOMUN S/S, SINDANG S/S and MAJANG S/S governed by Seoul Power Transmission Center. If the system reliability is proved for a one year test in real power system, application of the system will be extended to the other substations.

  5. Soft x-ray amplification in lithium-like Al XI (154 /angstrom/) and Si XII (129 /angstrom/)

    International Nuclear Information System (INIS)

    Kim, D.; Skinner, C.H.; Wouters, A.; Valeo, E.; Voorhees, D.; Suckewer, S.

    1988-03-01

    Recent experiments on soft x-ray amplification in lithium-like ions in a CO 2 laser-produced recombining plasma confined in a magnetic field are presented. The maximum gain-length products observed are GL ≅ 3 to 4 for the 154 /angstrom/, 4f-3d transition in Al XI and GL (approxreverse arrowequal/ 1 to 2 for the 129 /angstrom/, 4f-3d transition in Si XII, respectively. A one-dimensional hydrodynamic code with a collisional-radiative atomic model was used to model the plasma and the theoretical predictions of gain agree well with the observations. Descriptions of both hydrodynamic and atomic physics code are given. 36 refs., 10 figs

  6. The role of CD154-CD40 versus CD28-B7 costimulatory pathways in regulating allogeneic Th1 and Th2 responses in vivo

    DEFF Research Database (Denmark)

    Kishimoto, K; Dong, V M; Issazadeh-Navikas, Shohreh

    2000-01-01

    We used signal transducer and activator of transcription 4 (STAT4) and STAT6 gene knockout (-/-) mice as recipients of fully mismatched cardiac allografts to study the role of T-cell costimulatory pathways in regulating allogeneic T-helper 1 (Th1) versus Th2 responses in vivo. STAT4(-/-) mice have...... impaired Th1 responses, whereas STAT6(-/-) mice do not generate normal Th2 responses. Cardiac allografts from C57BL/6 mice were transplanted into normal wild-type (WT), STAT4(-/-), and STAT6(-/-) BALB/c recipients. STAT4(-/-) and STAT6(-/-) mice rejected their grafts with the same tempo as untreated WT....... Furthermore, there was a similar differential effect of CD28-B7 versus CD154-CD40 blockade in inhibiting immune responses in animals immunized with ovalbumin and complete Freund's adjuvant. These novel data indicate that Th1 and Th2 cells are differentially regulated by CD28-B7 versus CD154-CD40 costimulation...

  7. Gamma-ray multiplicity moments from 86Kr reactions on 144sup(,)154Sm at 490 MeV

    International Nuclear Information System (INIS)

    Christensen, P.R.; Folkmann, F.; Hansen, O.; Nathan, O.; Trautner, N.; Videbaek, F.; Werf, S.Y. van der; Britt, H.C.; Chestnut, R.P.; Freiesleben, H.

    1980-01-01

    Gamma-ray multiplicity moments have been measured for reactions induced in the collision systems 86 Kr + 144 Sm and 86 Kr+ 154 Sm at 490 MeV lab bombarding energy. Differential cross sections for reaction products from Fe to In were also measured. Angular momentum distribution moments are derived from the multiplicity moments for deep inelastic collisions. The angular momentum transfer results are discussed in terms of the sticking picture and other models for deep inelastic collisions. It is demonstrated that the measured second moments are larger than expected from the standard sticking prescription and may provide a significant test of other models. (orig.)

  8. CDCC calculations of fusion of 6Li with targets 144Sm and 154Sm: effect of resonance states

    Science.gov (United States)

    Gómez Camacho, A.; Lubian, J.; Zhang, H. Q.; Zhou, Shan-Gui

    2017-12-01

    Continuum Discretized Coupled-Channel (CDCC) model calculations of total, complete and incomplete fusion cross sections for reactions of the weakly bound 6Li with 144,154Sm targets at energies around the Coulomb barrier are presented. In the cluster structure frame of 6Li→α+d, short-range absorption potentials are considered for the interactions between the ground state of the projectile 6Li and α-d fragments with the target. In order to separately calculate complete and incomplete fusion and to reduce double-counting, the corresponding absorption potentials are chosen to be of different range. Couplings to low-lying excited states 2+, 3- of 144Sm and 2+, 4+ of 154Sm are included. So, the effect on total fusion from the excited states of the target is investigated. Similarly, the effect on fusion due to couplings to resonance breakup states of 6Li, namely, l=2, J π =3+,2+,1+ is also calculated. The latter effect is determined by using two approaches, (a) by considering only resonance state couplings and (b) by omitting these states from the full discretized energy space. Among other things, it is found that both resonance and non-resonance continuum breakup couplings produce fusion suppression at all the energies considered. A. Gómez Camacho from CONACYT, México, J. Lubian from CNPq, FAPERJ, Pronex, Brazil. S.G.Z was partly supported by the NSF of China (11120101005, 11275248, 11525524, 11621131001, 11647601, 11711540016), 973 Program of China (2013CB834400) and the Key Research Program of Frontier Sciences of CAS. H.Q.Z. from NSF China (11375266)

  9. The non-peptide CRH1-antagonist CP-154,526 elicits a paradoxical route-dependent activation of the HPA axis.

    Science.gov (United States)

    Zaretsky, Dmitry V; Zaretskaia, Maria V; Sarkar, Sumit; Rusyniak, Daniel E; DiMicco, Joseph A

    2017-07-13

    The corticotropin-releasing hormone (CRH) plays an important role in mediating physiological response to stress and is thought to be involved in the development of various psychiatric disorders. In this paper, we compare the differences between the effect of intraperitoneal (i.p.) and intraarterial (i.a.) administration of the non-peptide CRH 1 antagonist CP-154,526 (CP) (10 and 20mg/kg) on plasma adrenocorticotropic hormone levels (ACTH), heart rate, MAP, and c-Fos expression in the paraventricular nucleus of the hypothalamus. Intraperitoneal, but not i.a., injection of CP resulted in an increase in plasma ACTH (from 105±13 to 278±51pg/ml after 20mg/kg). This effect was accompanied by a dramatic increase in c-Fos expression in cells immunoreactive for CRH in the paraventricular nucleus of the hypothalamus. When the drug was administered i.p., CP-induced activation of the HPA appears to mask the inhibitory effect of CP on stress-induced ACTH secretion, an effect which was readily apparent when the drug was given i.a. Intraperitoneal administration of CP also increased the baseline MAP which may account for previous reports that treatment with this drug attenuated the increases associated with stress. CP given by either route had no effect on baseline heart rate or stress-induced tachycardia. Thus, in all studies in which CP 154,526 is given, the route of delivery must be given careful consideration. Copyright © 2017 Elsevier B.V. All rights reserved.

  10. Ceramic material suitable for repair of a space vehicle component in a microgravity and vacuum environment, method of making same, and method of repairing a space vehicle component

    Science.gov (United States)

    Riedell, James A. (Inventor); Easler, Timothy E. (Inventor)

    2009-01-01

    A precursor of a ceramic adhesive suitable for use in a vacuum, thermal, and microgravity environment. The precursor of the ceramic adhesive includes a silicon-based, preceramic polymer and at least one ceramic powder selected from the group consisting of aluminum oxide, aluminum nitride, boron carbide, boron oxide, boron nitride, hafnium boride, hafnium carbide, hafnium oxide, lithium aluminate, molybdenum silicide, niobium carbide, niobium nitride, silicon boride, silicon carbide, silicon oxide, silicon nitride, tin oxide, tantalum boride, tantalum carbide, tantalum oxide, tantalum nitride, titanium boride, titanium carbide, titanium oxide, titanium nitride, yttrium oxide, zirconium diboride, zirconium carbide, zirconium oxide, and zirconium silicate. Methods of forming the ceramic adhesive and of repairing a substrate in a vacuum and microgravity environment are also disclosed, as is a substrate repaired with the ceramic adhesive.

  11. Numerical simulations of the cascades of the nuclei {sup 152,154,156}Dy with self-consistent collective strength functions

    Energy Technology Data Exchange (ETDEWEB)

    Khoo, T.L.; Lauritsen, T.; Martin, V.; Egido, J.L. [Universidad Autonoma de Madrid (Spain)

    1995-08-01

    Mean-field theories predict phase transitions in nuclei, such as a transition from collective to oblate shapes. However, fluctuations in the finite nucleus smear out the transition, and it is an interesting problem in mesoscopic physics to search for a remnant signature of the phase transition. Temperature-dependent Hartree-Fock theory predicts that the collective-to-oblate phase transition boundaries occur in a domain that can be favorably probed in experiments in {sup 152,154,156}Dy. These calculations were motivated by our past measurements of the quasicontinuum E2 spectra in these nuclei.

  12. Retrospective evaluation of coyote attacks in dogs: 154 cases (1997-2012).

    Science.gov (United States)

    Frauenthal, Virginia M; Bergman, Philip; Murtaugh, Robert J

    2017-05-01

    To describe the clinical presentation and outcome of known attacks in client-owned dogs caused by the common coyote, Canis latrans. Retrospective observational study. Private referral hospital. One hundred fifty-four client-owned dogs known to be attacked by coyotes. None. Records from a private referral hospital from May 1997 through December 2012 were reviewed. Time of day and month/season of year, signalment, body temperature, heart rate, respiratory rate, body weight, location and severity of wounds inflicted, common injuries, length of hospitalization, necessity of surgical wound repair under anesthesia, antimicrobial use and mortality were recorded. Eighty-six percent of dogs presenting following coyote attack weighed Dogs with bite wounds to the thorax had the highest mortality at 21.3%. Criteria for systemic inflammatory response syndrome (SIRS) based on admission vital signs were met in 58.8% of dogs and the presence of SIRS was significantly associated with mortality (P hernia (9/154; 5.8%), and abdominal penetrating wounds (8/146; 5.5%). Dogs dogs are a problem in Southern California and are associated with substantial morbidity and mortality, especially in dogs with wounds to the thorax. Aggressive management involving surgical wound repair was associated with survival to discharge. © Veterinary Emergency and Critical Care Society 2017.

  13. Star formation in the outskirts of DDO 154: A top-light IMF in a nearly dormant disc

    Science.gov (United States)

    Watts, Adam B.; Meurer, Gerhardt R.; Lagos, Claudia D. P.; Bruzzese, Sarah M.; Kroupa, Pavel; Jerabkova, Tereza

    2018-04-01

    We present optical photometry of Hubble Space Telescope (HST) ACS/WFC data of the resolved stellar populations in the outer disc of the dwarf irregular galaxy DDO 154. The photometry reveals that young main sequence stars are almost absent from the outermost HI disc. Instead, most are clustered near the main stellar component of the galaxy. We constrain the stellar initial mass function (IMF) by comparing the luminosity function of the main sequence stars to simulated stellar populations assuming a constant star formation rate over the dynamical timescale. The best-fitting IMF is deficient in high mass stars compared to a canonical Kroupa IMF, with a best-fit slope α = -2.45 and upper mass limit MU = 16 M⊙. This top-light IMF is consistent with predictions of the Integrated Galaxy-wide IMF theory. Combining the HST images with HI data from The HI Nearby Galaxy Survey Treasury (THINGS) we determine the star formation law (SFL) in the outer disc. The fit has a power law exponent N = 2.92 ± 0.22 and zero point A = 4.47 ± 0.65 × 10-7 M⊙ yr-1 kpc-2. This is depressed compared to the Kennicutt-Schmidt Star Formation Law, but consistent with weak star formation observed in diffuse HI environments. Extrapolating the SFL over the outer disc implies that there could be significant star formation occurring that is not detectable in Hα. Last, we determine the Toomre stability parameter Q of the outer disc of DDO 154 using the THINGS HI rotation curve and velocity dispersion map. 72% of the HI in our field has Q ≤ 4 and this incorporates 96% of the observed MS stars. Hence 28% of the HI in the field is largely dormant.

  14. BRCA2 Mutations in 154 Finnish Male Breast Cancer Patients

    Directory of Open Access Journals (Sweden)

    Kirsi Syrjäkoski

    2004-09-01

    Full Text Available The etiology and pathogenesis of male breast cancer (MBC are poorly known. This is due to the fact that the disease is rare, and large-scale genetic epidemiologic studies have been difficult to carry out. Here, we studied the frequency of eight recurrent Finnish BRCA2 founder mutations in a large cohort of 154 MBC patients (65% diagnosed in Finland from 1967 to 1996. Founder mutations were detected in 10 patients (6.5%, eight of whom carried the 9346(-2 A>G mutation. Two novel mutations (4075 delGT and 5808 del5 were discovered in a screening of the entire BRCA2 coding region in 34 samples. However, these mutations were not found in the rest of the 120 patients studied. Patients with positive family history of breast and/or ovarian cancer were often BRCA2 mutation carriers (44%, whereas those with no family history showed a low frequency of involvement (3.6%; P < .0001. Finally, we found only one Finnish MBC patient with 999 dell, the most common founder mutation in Finnish female breast cancer (FBC patients, and one that explains most of the hereditary FBC and MBC cases in Iceland. The variation in BRCA2 mutation spectrum between Finnish MBC patients and FBC patients in Finland and breast cancer patients in Iceland suggests that modifying genetic and environmental factors may significantly influence the penetrance of MBC and FBC in individuals carrying germline BRCA2 mutations in some populations.

  15. Enfoque terapéutico en 154 pacientes con acromegalia

    Directory of Open Access Journals (Sweden)

    Marcos P. Manavela

    2010-08-01

    Full Text Available La acromegalia es una enfermedad poco frecuente producida en más del 95% de los casos por un tumor hipofisario secretor de hormona de crecimiento (GH. Las manifestaciones clínicas están asociadas a síntomas locales por crecimiento del tumor o a las consecuencias orgánicas y metabólicas secundarias a la hipersecreción de GH. Debido a la alta morbilidad y mortalidad asociadas a la acromegalia, un tratamiento individualizado y optimizado para cada paciente es fundamental. Informamos el enfoque terapéutico de nuestro servicio de endocrinología en la atención de 154 pacientes con acromegalia. Utilizando criterios bioquímicos estrictos, con la cirugía logramos un 32% de remisión global, tasa relativamente baja debido fundamentalmente a que la mayor parte de los pacientes presentaban macroadenomas con un alto porcentaje de invasividad local. Con radioterapia complementaria o como tratamiento inicial se logró la remisión en el 65.4% de los pacientes irradiados. El 14.0% de los pacientes controlaron la enfermedad utilizando agonistas dopaminérgicos solos o combinados con otra droga, mientras que aquellos que utilizaron análogos de la somatostatina normalizaron los parámetros bioquímicos en un 45.7% de los casos. En conclusión, con los diferentes tratamientos utilizados obtuvimos el control de la acromegalia en el 55.2% de los casos, esperando optimizar el tratamiento de estos pacientes en la medida en que contemos con y tengamos acceso a nuevas herramientas terapéuticas.

  16. Proton and O sup(2-) ion diffusion studied by γ-γ angular correlation and by impedance spectroscopy

    International Nuclear Information System (INIS)

    Oliveira Damasceno, O. de.

    1988-01-01

    The interaction of sup(181) Ta quadrupole momentum with electric field gradient was measured by perturbed angular correlation spectroscopy in polycrystalline samples of hafnium hydride and hafnium oxide. The measurements were done as function of the temperature, in cubic and tetragonal phases of hafnium hydride. In the cubic phase, spin relaxation effects related to proton diffusion with activation energy of 0.43 ± 0.05eV were observed, and in the tetragonal phase, the interaction was purely static. The hafnium oxide was studied in cubic phase stabilized by addition of calcium oxide or magnesium oxide. Relaxation effects probably due to O sup(2-) ion diffusion were verified. The protonic conduction in K H sub(2) PO sub(4) was studied by impedance spectroscopy, in pellets prepared by melting or powder compression using silver and platinum electrodes. In the case of silver electrodes, in the low frequency region, the impedance spectrum tends to a 45 sup(0) typical line of the diffusion process. It was attributed to hydrogen injection in the electrode. Heating k H sub(2) PO sub(4) at about 230 sup(0)C modifies significantly the electric properties. Two relaxation annealing reduced conductivities to constant values independently of preparation method. (author)

  17. 154/34,5 kV Güç Transformatörleri için Diferansiyel Koruma Rölesi Koordinasyonu Benzetimi

    Directory of Open Access Journals (Sweden)

    Ozan AKDAĞ

    2018-03-01

    Full Text Available Güç transformatörleri, güç sistemlerinde gerilimin seviyesini değiştirmede kullanılır. Güç transformatörleri üretim santrallerindeki elektrik enerjisinin gerilim seviyesini yükselterek iletim sistemine aktarır. Türkiye’de iletim gerilimi genelde 380 kV/154 kV’ dur. Bu seviyedeki gerilim, indirici merkezlerinde yaklaşık 34,5 kV gerilim seviyesine düşürülür. Güç transformatörleri güç sistemindeki teçhizatlar içinde en pahalı ve en önemlilerinden biridir. Bu yüzden güç transformatörlerini, güç sistemindeki çeşitli arıza durumlarından ya da kendi içinde oluşan arızalardan korumak önemlidir.   Bu işlem çeşitli koruma röleleri ile sağlanırken, genelde diferansiyel koruma röleleri kullanılır. Bu çalışmada temel özelliklere sahip bir koruma rölesinin benzetimi yapılarak, 154/34,5 kV bir güç transformatörünün koruma koordinasyonu analizi yapılmıştır. Güç sisteminin modellenmesi ve temel diferansiyel koruma rölesi benzetimde DigSilent güç sistemleri analiz programı kullanılmıştır.

  18. Lowering the environmental impact of high-kappa/ metal gate stack surface preparation processes

    Science.gov (United States)

    Zamani, Davoud

    ABSTRACT Hafnium based oxides and silicates are promising high-κ dielectrics to replace SiO2 as gate material for state-of-the-art semiconductor devices. However, integrating these new high-κ materials into the existing complementary metal-oxide semiconductor (CMOS) process remains a challenge. One particular area of concern is the use of large amounts of HF during wet etching of hafnium based oxides and silicates. The patterning of thin films of these materials is accomplished by wet etching in HF solutions. The use of HF allows dissolution of hafnium as an anionic fluoride complex. Etch selectivity with respect to SiO2 is achieved by appropriately diluting the solutions and using slightly elevated temperatures. From an ESH point of view, it would be beneficial to develop methods which would lower the use of HF. The first objective of this study is to find new chemistries and developments of new wet etch methods to reduce fluoride consumption during wet etching of hafnium based high-κ materials. Another related issue with major environmental impact is the usage of large amounts of rinsing water for removal of HF in post-etch cleaning step. Both of these require a better understanding of the HF interaction with the high-κ surface during the etching, cleaning, and rinsing processes. During the rinse, the cleaning chemical is removed from the wafers. Ensuring optimal resource usage and cycle time during the rinse requires a sound understanding and quantitative description of the transport effects that dominate the removal rate of the cleaning chemicals from the surfaces. Multiple processes, such as desorption and re-adsorption, diffusion, migration and convection, all factor into the removal rate of the cleaning chemical during the rinse. Any of these processes can be the removal rate limiting process, the bottleneck of the rinse. In fact, the process limiting the removal rate generally changes as the rinse progresses, offering the opportunity to save resources

  19. High-efficiency, 154  W CW, diode-pumped Raman fiber laser with brightness enhancement.

    Science.gov (United States)

    Glick, Yaakov; Fromzel, Viktor; Zhang, Jun; Ter-Gabrielyan, Nikolay; Dubinskii, Mark

    2017-01-20

    We demonstrate a high-power, high-efficiency Raman fiber laser pumped directly by laser diode modules at 978 nm. 154 W of CW power were obtained at a wavelength of 1023 nm with an optical to optical efficiency of 65%. A commercial graded-index (GRIN) core fiber acts as the Raman fiber in a power oscillator configuration, which includes spectral selection to prevent generation of the second Stokes. In addition, brightness enhancement of the pump beam by a factor of 8.4 is attained due to the Raman gain distribution profile in the GRIN fiber. To the best of our knowledge this is the highest power and highest efficiency Raman fiber laser demonstrated in any configuration allowing brightness enhancement (i.e., in either cladding-pumped configuration or with GRIN fibers, excluding step-index core pumped), regardless of pumping scheme (i.e., either diode pumped or fiber laser pumped).

  20. LHC dipoles flood into CERN : the dipole nr 154 crowns the efforts of the LHC teams for increasing the fabrication rate of the magnets.

    CERN Multimedia

    Maximilien Brice

    2003-01-01

    On 3 December the "tableau" on the 4th floor in building 30 indicated 1078 dipoles to completion - or in other words, 154 dipoles had by this day been delivered to CERN, enough to complete the first octant of the machine. CERN has also now received enough superconducting cable - the "heart" of the magnets - for 600 dipoles, nearly half the total number of 1232.

  1. 11th AINSE Plasma Physics Conference 1977, 7th and 8th February, 1977, Lucas Heights, NSW (Australia), 9th February, 1977, University of Sydney. Abstracts of Papers 1-54

    Energy Technology Data Exchange (ETDEWEB)

    Walsh, C. J. [ed.

    1977-02-15

    Abstracts of papers 1-54 scheduled for oral presentation at the 11th AINSE Plasma Physics Conference are included. No introductory or summary information is provided. Each page consists of the title, authors, organization affiliation, and abstract.

  2. Incidence of infection in 39-month-old ewes with TMEM154 diplotypes "1 1," "1 3," and "3 3" after natural exposure to ovine progressive pneumonia virus.

    Science.gov (United States)

    Leymaster, K A; Chitko-McKown, C G; Heaton, M P

    2015-01-01

    Production and well-being of sheep and goats in many countries are harmfully impacted by small ruminant lentiviruses (SRLV) that cause incurable, progressive diseases. Susceptibility to ovine progressive pneumonia virus (OPPV), the North American form of SRLV, is influenced by variants of the ovine transmembrane protein 154 gene (TMEM154). The experimental objective was to estimate additive and dominance effects of TMEM154 haplotypes 1 and 3 on susceptibility of breeding ewes to infection after natural exposure to OPPV from birth to 39 mo of age. Sires and dams were heterozygous for TMEM154 haplotypes 1 and 3, producing ewe lambs with diplotypes "1 1," "1 3," and "3 3." These lambs were raised by mature, infected dams to ensure natural, maternal exposure to OPPV. Ewe lambs (n = 108) were kept for breeding and joined an infected flock of ewes to guarantee natural, nonmaternal exposure to OPPV. Ewes were bred to lamb at 1, 2, and 3 yr of age. Serum samples were collected at breeding, 1 mo before lambing and shortly after weaning each year to monitor infection status to 39 mo of age. During the experiment, 9 of the 108 ewes died while uninfected and data collected on these ewes were not analyzed. Infection status of the remaining 99 ewes at 39 mo of age was analyzed using logistic regression procedures. Effects of ewe type of birth, ewe type of rearing, and breed type of dam were not detected (P > 0.10), and the estimated sire variance component was nil. Ewe diplotype affected infection status (P ewes with diplotypes "1 1," "1 3," and "3 3" were 0.10, 0.88, and 0.89, respectively, and confidence intervals for diplotypes "1 3" and "3 3" were distinct from "1 1." Haplotype 3 was completely dominant to haplotype 1 at 39 mo of age. The probability of infection for ewes with either diplotype "1 3" or "3 3" averaged 8.5 times that of ewes with diplotype "1 1." Diplotype "1 3" and "3 3" ewes were highly susceptible to nonmaternal transmission of OPPV, in contrast to

  3. Solvent extraction columns

    International Nuclear Information System (INIS)

    Middleton, P.; Smith, J.R.

    1979-01-01

    In pulsed columns for use in solvent extraction processes, e.g. the reprocessing of nuclear fuel, the horizontal perforated plates inside the column are separated by interplate spacers manufactured from metallic neutron absorbing material. The spacer may be in the form of a spiral or concentric circles separated by radial limbs, or may be of egg-box construction. Suitable neutron absorbing materials include stainless steel containing boron or gadolinium, hafnium metal or alloys of hafnium. (UK)

  4. Effects of TMEM154 haplotypes 1 and 3 on susceptibility to ovine progressive pneumonia virus following natural exposure in sheep.

    Science.gov (United States)

    Leymaster, K A; Chitko-McKown, C G; Clawson, M L; Harhay, G P; Heaton, M P

    2013-11-01

    Small ruminant lentiviruses (SRLV) adversely affect production and well-being of sheep and goats throughout much of the world. The SRLV, including ovine progressive pneumonia virus (OPPV) in North America, cause lifetime infections, and management procedures to eradicate or reduce disease prevalence are costly. Variants of ovine transmembrane protein 154 gene (TMEM154) affect susceptibility to OPPV. The primary experimental objective was to estimate additive and dominance effects of TMEM154 haplotypes 1 and 3 on susceptibility to OPPV infection following natural exposure. A group of 187 trial lambs was born and raised by mature, infected ewes to ensure natural exposure to OPPV. Parents of trial lambs were heterozygous for haplotypes 1 and 3, producing lambs with diplotypes "1 1," "1 3," and "3 3." A group of 20 sentinel lambs was born and raised by mature, uninfected ewes that were diplotype "1 1." Sentinel lambs had diplotypes "1 1" and "1 3," being sired by the same set of rams as trial lambs. Trial and sentinel lambs were comingled during the experiment. Lambs were weaned at 60 d of age, bled 1 wk after weaning, and thereafter at intervals of 4 or 5 wk until 9 mo of age when OPPV infection status was determined by use of a competitive enzyme-linked immunosorbent assay. Only 1 sentinel lamb became infected. Infection status of trial lambs was analyzed using logistic regression procedures to account for the binary nature of infection status and random effects of sires. Effects of sex, type of birth, type of rearing, age of dam, breed type of dam, and sires were not detected (P>0.20). Infection status was affected by diplotype of lamb (P=0.005), with additive (P=0.002) and dominance (P=0.052) effects identified. Predicted probabilities of infection for lambs with diplotypes "1 1," "1 3," and "3 3" were 0.094, 0.323, and 0.346, respectively. Confidence intervals for probabilities of infection for diplotypes "1 3" and "3 3" were similar, but distinct from diplotype

  5. Cobalt catalysts for the conversion of methanol and for Fischer-tropsch synthesis to produce hydrocarbons

    International Nuclear Information System (INIS)

    Mauldin, C.H.; Davis, S.M.; Arcuri, K.B.

    1987-01-01

    A regeneration stable catalyst is described for the conversion at reaction conditions of methanol or synthesis gas to liquid hydrocarbons which consists essentially of from about 2 percent to about 25 percent cobalt, based on the weight of the catalyst composition, composited with titania, or a titania-containing support, to which is added sufficient of a zirconium, hafnium, cerium, or uranium promoter to provide a weight ratio of the zirconium, hafnium, cerium, or uranium metal:cobalt greater than about 0.101:1

  6. Application of energy-dispersive XRF technique in the hydrometallurgy study of local zircon

    International Nuclear Information System (INIS)

    Meor Yusoff Sulaiman; Kamaruddin Hussin; Azizan Aziz

    1996-01-01

    In this study, energy-dispersive X-ray Fluorescence (EDXR-F) was used to analyse the elemental composition of the starting zircon mineral associated elements in the leaching solution. Besides analysing the major elements i.e. of zirconium, silicon and hafnium, trace elemental analysis for iron, titanium and the naturally occurring radioactive element thorium and uranium are important in establishing the grades of Malaysian zircon. The technique was also used in determine the optimum conditions for zirconium and hafnium recovery during the leaching process

  7. Potentiodynamic polarization studies of bulk amorphous alloy Zr57Cu15.4Ni12.6Al10Nb5 and Zr59Cu20Ni8Al10Ti3 in aqueous HNO3 media

    International Nuclear Information System (INIS)

    Sharma, Poonam; Dhawan, Anil; Jayraj, J.; Kamachi Mudali, U.

    2013-01-01

    The potentiodynamic polarization studies were carried out on Zr based bulk amorphous alloy Zr 57 Cu 15.4 Ni 12.6 Al 10 Nb 5 and Zr 59 Cu 20 Ni 8 Al 10 Ti 3 in solutions of 1 M, 6 M and 11.5 M HNO 3 aqueous media at room temperature. As received specimens of Zr 57 Cu 15.4 Ni 12.6 Al 10 Nb 5 (5 mm diameter rod) and Zr 59 Cu 20 Ni 8 Al 10 Ti 3 (3 mm diameter rod) were polished with SiC paper before testing them for potentiodynamic polarization studies. The amorphous nature of the specimens was checked by X-ray diffraction. The bulk amorphous alloy Zr 59 Cu 20 Ni 8 Al 10 Ti 3 shows the better corrosion resistance than Zr 57 Cu 15.4 Ni 12.6 Al 10 Nb 5 alloy in the aqueous HNO 3 media as the value of the corrosion current density (I corr ) for Zr 57 Cu 15.4 Ni 12.6 Al 10 Nb 5 alloy were found to be more than Zr 59 Cu 20 Ni 8 Al 10 Ti 3 alloy in aqueous HNO 3 media. The improved corrosion resistance of Zr 59 Cu 20 Ni 8 Al 10 Ti 3 alloy is possibly due to the presence of Ti and formation of TiO 2 during anodic oxidation. Both Zr based bulk amorphous alloys shows wider passive range at lower concentration of nitric acid and the passive region gets narrowed down with the increase in concentration. A comparison of data obtained from both the Zr-based bulk amorphous alloys is made and results are discussed in the paper. (author)

  8. Reactive evaporation of low-defect density hafnia

    International Nuclear Information System (INIS)

    Chow, R.; Falabella, S.; Loomis, G.E.; Rainer, F.; Stolz, C.J.; Kozlowski, M.R.

    1993-01-01

    Motivation for this work includes observations at Lawrence Livermore National Laboratory of a correlation between laser damage thresholds and both the absorption and the nodular-defect density of coatings. Activated oxygen is used to increase the metal-oxidation kinetics at the coated surface during electron-beam deposition. A series of hafnia layers are made with various conditions: two μ-wave configuations, two sources (hafnium and hafnia), and two reactive oxygen pressures. Laser damage thresholds (1064-nm, 10-ns pulses), absorption (at 511 nm), and nodular-defect densities from these coatings are reported. The damage thresholds are observed to increase as the absorption of the coatings decreases. However, no significant increase in damage thresholds are observed with the coatings made from a low nodular-defect density source material (hafnium). Hafnia coatings can be made from hafnium sources that have lower nodular-defect densities, lower absorption, and damage thresholds that are comparable with coatings made from a conventional hafnia source

  9. Tests for removal of Co-60 and Eu-154 from irradiated graphite in the TRIGA Reactor

    International Nuclear Information System (INIS)

    Arsene, Carmen

    2009-01-01

    The irradiated graphite in Romania is mainly generated in the thermal columns of TRIGA and WWER-S research reactors (about 9 tones). It was found that the radionuclide content of the graphite irradiated in the TRIGA research reactor is mainly due to C-14 (103 Bq/g), Eu-152 (600-700 Bq/g) and Co-60 (130-150 Bq/g) and low amounts of Eu-154 and Cs-137, depending on location in the thermal column and on irradiation history. In order to minimize the waste inventory and volume in view of their final disposal, in the present paper we show the results of experiments performed for developing and optimizing methods for the chemical decontamination of the irradiated graphite. These procedures are based on strong alkaline solutions for Eu-152 and strong acid solutions for Co-60. The influence of the process parameters on the decontamination factor is investigated. (authors)

  10. Assessment of occupational exposure to magnetic fields in high-voltage substations (154/34.5 kV)

    International Nuclear Information System (INIS)

    Helhel, S.; Ozen, S.

    2008-01-01

    This work proposes the survey of magnetic field measurements taken in 154/31.5 kV substations in the city of Antalya for occupational exposure assessment. For measurements, three substations have been taken into account, where four occupants are present for each 8 h of shift, which means 12 occupants are present during the day. Operator desks at three different substations read a lowest magnetic field of 0.3 μT at minimum loaded season and reached up to 1 μT at maximum loaded season, which means operators exposed to a magnetic field of ≥ 0.3 μT 8 h d -1 . In switch gear regions, maximum magnetic field reading is 23 μT at minimum loaded season and reached up to 70 μT. Outdoor magnetic field measurement at circuit breaker region goes up to 62 μT with respect to operator heights. (authors)

  11. About 42% of 154 remains from the "Battle of Le Mans", France (1793) belong to women and children: Morphological and genetic evidence.

    Science.gov (United States)

    Thèves, Catherine; Cabot, Elodie; Bouakaze, Caroline; Chevet, Pierre; Crubézy, Éric; Balaresque, Patricia

    2016-05-01

    Mass graves were discovered in Le Mans and 154 skeletons were exhumed, representing a remarkable historical series of human remains from western France. We aimed to characterise the age-class and sex of these subjects, and to determine whether their profile fits with that of the Catholic and Royal Army of Vendée, who fought against the Republican Army during the Battle of Le Mans (12th-13th December, 1793). This atypical army was composed of male soldiers, but also of civilian people who followed the troops, including the elderly, children and women. In total 154 skeletons from nine mass graves were exhumed from 2009 to 2010. Two morphological methods were used to determine the sex of the subjects: the Probabilist Sexual Diagnosis (DSP) and Secondary Sexual Diagnosis (DSS) methods. Samples were handled cautiously to avoid any pre-laboratory contamination. Molecular genetic sex-typing using a recently developed assay was used to maximise sex-diagnosis of the ancient DNA samples, and 97 successful profiles including immatures were generated. Using morphological and genetic data combined, we successfully determined the sex of 93% of the subjects; 62% were male and 31% female. About 87% of subjects could be considered adults (>18 years old), 6% adolescents (15-19 years old) and 7% infants (Catholic and Royal Army) or passively (collateral victims from the civilian population of Le Mans). They represent 5-6% of the estimated 2500-3000 victims. Copyright © 2016 Elsevier Ireland Ltd. All rights reserved.

  12. Study of N-cinnamoylphenylhydroxylaminate solubility in water and organic solvents

    International Nuclear Information System (INIS)

    Pilipenko, A.T.; Shpak, Eh.A.; Samchuk, A.I.

    1975-01-01

    The composition of complexes of N-cinnamoylphenylhydroxylamine with copper, cadmium, lead, indium, iron, gallium, titanium, zirconium, hafnium, niobium, tantalum, tungsten, molybdenum and vanadium was determined. The solubility products of the N-cinnamoylphenylhydroxylaminates of copper, cadmium, indium, gallium and iron were determined by the method of measuring the solubility of precipitates in acid. The solubility of N-cinnamoylphenylhydroxalaminates of cadmium, indium, iron, titanium, zirconium, hafnium, niobium, tantalum, vanadium, molybdenum and tungsten in organic solvents was studied. Two-phase constants for the stability of the complexes were calculated. (author)

  13. A 1.5--4 Kelvin detachable cold-sample transfer system: Application to inertially confined fusion with spin-polarized hydrogens fuels

    International Nuclear Information System (INIS)

    Alexander, N.; Barden, J.; Fan, Q.; Honig, A.

    1990-01-01

    A compact cold-transfer apparatus for engaging and retrieving samples at liquid helium temperatures (1.5--4K), maintaining the samples at such temperatures for periods of hours, and subsequently inserting them in diverse apparatuses followed by disengagement, is described. The properties of several thermal radiation-insulating shrouds, necessary for very low sample temperatures, are presented. The immediate intended application is transportable target-shells containing highly spin-polarized deuterons in solid HD or D 2 for inertially confined fusion (ICF) experiments. The system is also valuable for unpolarized high-density fusion fuels, as well as for other applications which are discussed. 9 refs., 6 figs

  14. A de novo 11p12-p15.4 duplication in a patient with pharmacoresistant epilepsy, mental retardation, and dysmorphisms.

    Science.gov (United States)

    Coppola, Antonietta; Striano, Pasquale; Gimelli, Stefania; Ciampa, Clotilde; Santulli, Lia; Caranci, Ferdinando; Zuffardi, Orsetta; Gimelli, Giorgio; Striano, Salvatore; Zara, Federico

    2010-03-01

    We report a 22-year-old male patient with pharmacoresistant epilepsy, mental retardation and dysmorphisms. Standard cytogenetic analysis revealed a de novo interstitial duplication of the short arm of chromosome 11 (11p). High density array-CGH analysis showed that the rearrangement spans about 35Mb on chromosome 11p12-p15.4. Duplications of 11p are rare and usually involve the distal part of the chromosome arm (11p15), being not associated with epilepsy, whereas our patient showed a unique epileptic phenotype associated with mental retardation and dysmorphic features. The role of some rearranged genes in epilepsy pathogenesis in this patient is also discussed.

  15. Experimental Observations of Nuclear Activity in Deuterated Materials Subjected to a Low-Energy Photon Beam

    Science.gov (United States)

    Steinetz, Bruce M.; Benyo, Theresa L.; Pines, Vladimir; Pines, Marianna; Forsley, Lawrence P.; Westmeyer, Paul A.; Chait, Arnon; Becks, Michael D.; Martin, Richard E.; Hendricks, Robert C.; hide

    2017-01-01

    Exposure of highly deuterated materials to a low-energy (nom. 2 MeV) photon beam resulted in nuclear activity of both the parent metals of hafnium and erbium and a witness material (molybdenum) mixed with the reactants. Gamma spectral analysis of all deuterated materials, ErD2.8+C36D74+Mo and HfD2+C36D74+Mo, showed that nuclear processes had occurred as shown by unique gamma signatures. For the deuterated erbium specimens, posttest gamma spectra showed evidence of radioisotopes of erbium ((163)Er and (171)Er) and of molybdenum ((99)Mo and (101)Mo) and by beta decay, technetium (99mTc and 101Tc). For the deuterated hafnium specimens, posttest gamma spectra showed evidence of radioisotopes of hafnium (180mHf and 181Hf) and molybdenum ((99)Mo and (101)Mo), and by beta decay, technetium ((99m)Tc and (101)Tc). In contrast, when either the hydrogenated or non-gas-loaded erbium or hafnium materials were exposed to the gamma flux, the gamma spectra revealed no new isotopes. Neutron activation materials showed evidence of thermal and epithermal neutrons. CR-39 solid-state nuclear track detectors showed evidence of fast neutrons with energies between 1.4 and 2.5 MeV and several instances of triple tracks, indicating (is) greater than 10 MeV neutrons. Further study is required to determine the mechanism causing the nuclear activity.

  16. Aperture-time of oxygen-precursor for minimum silicon incorporation into the interface-layer in atomic layer deposition-grown HfO{sub 2}/Si nanofilms

    Energy Technology Data Exchange (ETDEWEB)

    Mani-Gonzalez, Pierre Giovanni [CINVESTAV-Unidad Querétaro, Querétaro 76230, Querétaro, Mexico and Departamento de Física y Matemáticas, Instituto de Ingeniería y Tecnología, Universidad Autónoma de Ciudad Juárez, Ave. Del Charro 450, Cd. Juárez C.P. 32310, Chihuahua (Mexico); Vazquez-Lepe, Milton Oswaldo [CINVESTAV-Unidad Querétaro, Querétaro 76230, Querétaro, Mexico and Departamento de Ingeniería de Proyectos, Universidad de Guadalajara, Guadalajara 45100, Jalisco (Mexico); Herrera-Gomez, Alberto, E-mail: aherrera@qro.cinvestav.mx [CINVESTAV-Unidad Querétaro, Querétaro 76230, Querétaro (Mexico)

    2015-01-15

    Hafnium oxide nanofilms were grown with atomic layer deposition on H-terminated Si (001) wafers employing tetrakis dimethyl amino hafnium (TDMA-Hf) and water as precursors. While the number of cycles (30) and the aperture-time for TDMA-Hf (0.08 s) were kept constant, the aperture-time (τ{sub H{sub 2O}}) for the oxidant-agent (H{sub 2}O) was varied from 0 to 0.10 s. The structure of the films was characterized with robust analysis employing angle-resolved x-ray photoelectron spectroscopy. In addition to a ∼1 nm hafnium oxide layer, a hafnium silicate interface layer, also ∼1 nm thick, is formed for τ{sub H{sub 2O}} > 0. The incorporation degree of silicon into the interface layer (i.e., the value of 1 − x in Hf{sub x}Si{sub 1−x}O{sub y}) shows a minimum of 0.32 for τ{sub H{sub 2O}} = 0.04 s. By employing the simultaneous method during peak-fitting analysis, it was possible to clearly resolve the contribution from the silicate and from oxide to the O 1s spectra, allowing for the assessment of the oxygen composition of each layer as a function of oxidant aperture time. The uncertainties of the peak areas and on the thickness and composition of the layers were calculated employing a rigorous approach.

  17. Preparation of refractory cermet structures for lithium compatibility testing

    Science.gov (United States)

    Heestand, R. L.; Jones, R. A.; Wright, T. R.; Kizer, D. E.

    1973-01-01

    High-purity nitride and carbide cermets were synthesized for compatability testing in liquid lithium. A process was developed for the preparation of high-purity hafnium nitride powder, which was subsequently blended with tungsten powder or tantalum nitride and tungsten powders and fabricated into 3 in diameter billets by uniaxial hot pressing. Specimens were then cut from the billets for compatability testing. Similar processing techniques were applied to produce hafnium carbide and zirconium carbide cermets for use in the testing program. All billets produced were characterized with respect to chemistry, structure, density, and strength properties.

  18. The vibrational spectra of some tetrachlorides in rare gas matrices with particular reference to the molecular shapes of ThCl4 and UCl4

    International Nuclear Information System (INIS)

    Arthers, S.A.; Beattie, I.R.

    1984-01-01

    Infrared spectra of tin, lead, hafnium, thorium, and uranium tetrachlorides isolated in inert gas matrices are reported. The results obtained for the tin, lead, and hafnium compounds follow the expected isotope patterns for a tetrahedral molecule except for the observation of additional weak features to high frequency of the all- 35 Cl isotopomers. By contrast for thorium tetrachloride the observed spectrum is not characteristic of a Tsub(d) molecule but can be fitted to a species with Csub(2v) symmetry. Similar results (although less detailed) were obtained for uranium tetrachloride. (author)

  19. Metal oxide targets produced by the polymer-assisted deposition method

    Energy Technology Data Exchange (ETDEWEB)

    Garcia, Mitch A., E-mail: mitch@berkeley.ed [Department of Chemistry, Room 446 Latimer Hall, University of California Berkeley, Berkeley, CA 94720-1460 (United States); Lawrence Berkeley National Laboratory, Berkeley, CA 94720 (United States); Ali, Mazhar N.; Chang, Noel N.; Parsons-Moss, T. [Department of Chemistry, Room 446 Latimer Hall, University of California Berkeley, Berkeley, CA 94720-1460 (United States); Lawrence Berkeley National Laboratory, Berkeley, CA 94720 (United States); Ashby, Paul D. [Lawrence Berkeley National Laboratory, Berkeley, CA 94720 (United States); Gates, Jacklyn M. [Department of Chemistry, Room 446 Latimer Hall, University of California Berkeley, Berkeley, CA 94720-1460 (United States); Lawrence Berkeley National Laboratory, Berkeley, CA 94720 (United States); Stavsetra, Liv [Lawrence Berkeley National Laboratory, Berkeley, CA 94720 (United States); Gregorich, Kenneth E.; Nitsche, Heino [Department of Chemistry, Room 446 Latimer Hall, University of California Berkeley, Berkeley, CA 94720-1460 (United States); Lawrence Berkeley National Laboratory, Berkeley, CA 94720 (United States)

    2010-02-11

    The polymer-assisted deposition (PAD) method was used to create crack-free homogenous metal oxide films for use as targets in nuclear science applications. Metal oxide films of europium, thulium, and hafnium were prepared as models for actinide oxides. Films produced by a single application of PAD were homogenous and uniform and ranged in thickness from 30 to 320 nm. Reapplication of the PAD method (six times) with a 10% by weight hafnium(IV) solution resulted in an equally homogeneous and uniform film with a total thickness of 600 nm.

  20. Metal oxide targets produced by the polymer-assisted deposition method

    International Nuclear Information System (INIS)

    Garcia, Mitch A.; Ali, Mazhar N.; Chang, Noel N.; Parsons-Moss, T.; Ashby, Paul D.; Gates, Jacklyn M.; Stavsetra, Liv; Gregorich, Kenneth E.; Nitsche, Heino

    2010-01-01

    The polymer-assisted deposition (PAD) method was used to create crack-free homogenous metal oxide films for use as targets in nuclear science applications. Metal oxide films of europium, thulium, and hafnium were prepared as models for actinide oxides. Films produced by a single application of PAD were homogenous and uniform and ranged in thickness from 30 to 320 nm. Reapplication of the PAD method (six times) with a 10% by weight hafnium(IV) solution resulted in an equally homogeneous and uniform film with a total thickness of 600 nm.

  1. Social Health Insurance-Based Simultaneous Screening for 154 Mutations in 19 Deafness Genes Efficiently Identified Causative Mutations in Japanese Hearing Loss Patients.

    Directory of Open Access Journals (Sweden)

    Kentaro Mori

    Full Text Available Sensorineural hearing loss is one of the most common neurosensory disorders in humans. The incidence of SNHL is estimated to be 1 in 500-1000 newborns. In more than half of these patients, the hearing loss is associated with genetic causes. In Japan, genetic testing for the patients with SNHL using the Invader assay to screen for 46 mutations in 13 deafness genes was approved by the Ministry of Health, Labour and Welfare for inclusion in social health insurance coverage in 2012. Furthermore, from August 2015, this genetic testing has been expanded to screen for 154 mutations in 19 deafness genes using targeted genomic enrichment with massively parallel DNA sequencing combined with the Invader assay and TaqMan genotyping. For this study we analyzed 717 unrelated Japanese hearing loss patients. The total allele frequency of 154 mutations in 19 deafness genes was 32.64% (468/1434 and the total numbers of cases associated with at least one mutation was 44.07% (316/717. Among these, we were able to diagnose 212 (30% patients, indicating that the present screening could efficiently identify causative mutations in hearing loss patients. It is noteworthy that 27 patients (3.8% had coexistent multiple mutations in different genes. Five of these 27 patients (0.7%, 5/717 overall were diagnosed with genetic hearing loss affected by concomitant with responsible mutations in more than two different genes. For patients identified with multiple mutations in different genes, it is necessary to consider that several genes might have an impact on their phenotypes.

  2. Evaluation of T-111 forced-convection loop tested with lithium at 13700C

    International Nuclear Information System (INIS)

    DeVan, J.H.; Long, E.L. Jr.

    1975-04-01

    A T-111 alloy (Ta--8 percent W--2 percent Hf) forced-convection loop containing molten lithium was operated 3000 h at a maximum temperature of 1370 0 C. Flow velocities up to 6.3 m/s were used. The results obtained in this forced-convection loop are very similar to those observed in lower velocity thermal-convection loops of T-111 containing lithium. Weight changes were determined at 93 positions around the loop. The maximum dissolution rate occurred at the maximum wall temperature of the loop and was less than 1.3 μ m/year. Mass transfer of hafnium, nitrogen, and, to a lesser extent, carbon occurred from the hotter to cooler regions. Exposed surfaces in the highest temperature region were found to be depleted in hafnium to a depth of 60 μ m with no detectable change in tungsten content. There was some loss in room-temperature tensile strength for specimens exposed to lithium at 1370 0 C, attributable to depletion of hafnium and nitrogen and to attendant grain growth. (U.S.)

  3. Separation of zirconium and hafnium; Separation du zirconium et de l'hafnium

    Energy Technology Data Exchange (ETDEWEB)

    Saint-James, D [Commissariat a l' Energie Atomique, Saclay (France).Centre d' Etudes Nucleaires

    1959-07-01

    This account is more chemical than metallurgical in character. The reason for this is that so-called 'nuclear metal' must fulfil standards of purity which only chemical processes can attain. This paper must therefore be considered as a preliminary study, from which the metallurgists can form an idea of the treatments leading to the production of the metal. (author) [French] Cet expose a un caractere chimique plutot que metallurgique. La raison en est que le metal dit 'nucleaire' a des exigences de purete que seuls des processus chimiques peuvent satisfaire. Il faut donc considerer cet expose comme un preliminaire, permettant de donner une idee aux metallurgistes des traitements qui aboutissent a l'elaboration du metal. (auteur)

  4. Surgical management of giant lumbar disc herniation: analysis of 154 patients over a decade.

    Science.gov (United States)

    Akhaddar, A; Belfquih, H; Salami, M; Boucetta, M

    2014-10-01

    We describe a decade of our experience in the surgical management of patients with giant lumbar intervertebral disc herniation (GILID). This is a case series of patients operated for a GILID between 2000 and 2009. Among 1334 patients eligible for the present study: 154 patients presented with GILID (study group) and 1180 patients without GILID (control group). Clinical symptoms and preoperative imaging results were obtained from medical records. Complications and long-term results were assessed. This retrospective study documents the characteristic features between patients with and without GILID. The difference in the incidence of female patients was statistically significant between the study group and the control group as was the mean duration of symptoms, hyperalgic radicular pain, bilaterality of symptoms, preoperative motor deficit, central location of lumbar disc herniation (LDH), contained herniation and recurrence of LDH. GILIDs are a distinct entity: they are distinctly uncommon compared with smaller herniations, patients were statistically more likely to be hyperalgic with bilateral radicular pain and often associated with neurological deficits. The majority of patients do not display a cauda equina syndrome (CES). Low lumbar disc sites are mostly affected and disc fragments are more likely to be central-uncontained. The recurrence rate is lower for GILIDs. Copyright © 2014 Elsevier Masson SAS. All rights reserved.

  5. Point defect engineering strategies to retard phosphorous diffusion in germanium

    KAUST Repository

    Tahini, H. A.; Chroneos, Alexander I.; Grimes, Robin W.; Schwingenschlö gl, Udo; Bracht, Hartmut A.

    2013-01-01

    The diffusion of phosphorous in germanium is very fast, requiring point defect engineering strategies to retard it in support of technological application. Density functional theory corroborated with hybrid density functional calculations are used to investigate the influence of the isovalent codopants tin and hafnium in the migration of phosphorous via the vacancy-mediated diffusion process. The migration energy barriers for phosphorous are increased significantly in the presence of oversized isovalent codopants. Therefore, it is proposed that tin and in particular hafnium codoping are efficient point defect engineering strategies to retard phosphorous migration. © the Owner Societies 2013.

  6. Particle-γ coincidence spectroscopy of the N = 90 nucleus {sup 154}Gd by (p, tγ)

    Energy Technology Data Exchange (ETDEWEB)

    Allmond, J.M. [Oak Ridge National Laboratory, Physics Division, Oak Ridge, TN (United States); University of Richmond, Department of Physics, Richmond, VA (United States); Beausang, C.W.; Ross, T.J.; Brooks, W.; Darakchieva, B.K. [University of Richmond, Department of Physics, Richmond, VA (United States); Humby, P. [University of Richmond, Department of Physics, Richmond, VA (United States); University of Surrey, Department of Physics, Guildford, Surrey (United Kingdom); Basunia, M.S.; Fallon, P.; Jeppesen, H.B.; McMahan, M.A.; Phair, L.; Rasmussen, J.O. [Lawrence Berkeley National Laboratory, Nuclear Science Division, Berkeley, CA (United States); Bernstein, L.A. [Lawrence Berkeley National Laboratory, Nuclear Science Division, Berkeley, CA (United States); University of California, Department of Nuclear Engineering, Berkeley, CA (United States); Bleuel, D.L.; Burke, J.T.; Scielzo, N.D. [Lawrence Livermore National Laboratory, Livermore, CA (United States); Brown, N. [Georgia Institute of Technology, School of Physics, Atlanta, GA (United States); Dudziak, K.R.; LeBlanc, J.D.; Meyer, D.A. [Rhodes College, Department of Physics, Memphis, TN (United States); Evans, K.E. [University of California, Department of Nuclear Engineering, Berkeley, CA (United States); Lesher, S.R. [Lawrence Livermore National Laboratory, Livermore, CA (United States); University of Wisconsin-La Crosse, Department of Physics, La Crosse, WI (United States); Stroberg, S.R. [University of California, Department of Nuclear Engineering, Berkeley, CA (United States); TRIUMF, Vancouver, British Columbia (Canada); Wiedeking, M. [Lawrence Livermore National Laboratory, Livermore, CA (United States); iThemba LABS, Department of Nuclear Physics, P.O. Box 722, Somerset West (South Africa)

    2017-03-15

    A segmented Si-telescope and HPGe array, STARS-LIBERACE, was used to study the {sup 156}Gd(p, tγ){sup 154}Gd direct reaction by particle-γ coincidence spectroscopy. New cross sections with a 25MeV proton beam are reported and compared to previous (p, t) and (t, p) studies. Furthermore, additional evidence for coexisting K{sup π} = 0{sub 1}{sup +}, 2{sub 1}{sup +} and 0{sub 2}{sup +}, 2{sub 2}{sup +} configurations at N = 90 is presented. Direct and indirect population patterns of the low-lying states are also explored. Review of the new and existing evidence favors an interpretation based on a configuration-dependent pairing interaction. The weakening of monopole pairing strength and an increase in quadrupole pairing strength could bring 2p-2h 0{sup +} states below 2Δ. This may account for a large number of the low-lying 0{sup +} states observed in two-nucleon transfer reactions. A hypothesis for the origin of the 0{sub 2}{sup +} and 0{sub 3}{sup +} states is provided. (orig.)

  7. Study of the nucleon spin structure functions: the E154 experiment at SLAC

    International Nuclear Information System (INIS)

    Sabatie, Franck

    1998-01-01

    In experiment E154 at SLAC, the spin dependent structure function g 1 n was measured by scattering longitudinally polarized 50 GeV electrons off a longitudinally polarized helium 3 target. We report the integral over the measured x range to be ∫ 0.014 0.7 g 1 n (x,5 GeV 2 )dx = -0.0348 ± 0.0033 ± 0.0043 ± 0.0014. We observe relatively large values of g 1 n at low x, calling into question the reliability of the data extrapolation down to x equal 0. Such a divergent behavior seems to disagree with the prediction of the Regge theory but can be quantitatively explained by perturbative QCD. Moreover, we have performed a NLO perturbative QCD analysis of the world data on g 1 , paying careful attention to both the theoretical hypothesis and the calculation of errors. Using a parametrization of the polarized parton distribution at a low scale, we can access the fraction of spin carried by quarks: ΔΣ = 29 ± 6 pc in the MS-bar scheme, and ΔΣ = 37 ± 7 pc in the AB scheme. The gluon contribution to the nucleon spin is not well enough constrained by the current data, but seems to lie between 0 and 2. This study allows us to extract the first moment of the g 1 structure function and we find agreement with the Bjorken sum rule expectations. (author) [fr

  8. Sauve-Kapandji operation for disorders of the distal radioulnar joint after Colles' fracture. Good results in 12 patients followed for 1.5-4 years

    DEFF Research Database (Denmark)

    Mikkelsen, Søren Søndergaard; Lindblad, Bent Erling; Larsen, Erik Roj

    1997-01-01

    Controversies continue concerning the treatment of the posttraumatic caput ulna syndrome. We have treated 12 patients, mean age 42 (23-77) years, with arthrodesis ad modum Sauve-Kapandji of the distal articulation between the radius and ulna, combined with resection of the ulnar neck. Before...... the operation, all patients had persistent ulnar wrist pain and restricted pronation-supination movement. At follow-up, after a mean of 2 (1.5-4) years, 8 patients had an excellent outcome, 3 a good, and 1 patient had a fair outcome. 10 patients had no wrist pain. The average grip-score improved from 53...

  9. PRODUCTION OF HAFNIUM METAL

    Science.gov (United States)

    Elger, G.W.; Boubel, R.W.

    1963-01-01

    This patent deals with a process of producing pure Hf metal from oxygen- contaminated gaseous Hf chloride. The oxygen compounds in the chioride gas are halogenated by contacting the gas at elevated temperature with Cl/sub 2/ in the presence of C. The Hf chloride, still in gaseous form, is contacted with molten Mg whereby Hf metal is formed and condensed on the Mg. (AEC)

  10. MIVOC method at the mVINIS ion source

    Directory of Open Access Journals (Sweden)

    Jovović Jovica

    2007-01-01

    Full Text Available Based on the metal-ions-from-volatile-compounds (MIVOC method with the mVINIS ion source, we have produced multiply charged ion beams from solid substances. Highly in tense, stable multiply charged ion beams of several solid substances with high melting points were extracted by using this method. The spectrum of multiply charged ion beams obtained from the element hafnium is presented here. For the first time ever, hafnium ion beam spectra were recorded at an electron cyclotron resonance ion source. Multiply charged ion beams from solid substances were used to irradiate the polymer, fullerene and glassy carbon samples at the channel for the modification of materials.

  11. Thickness independent reduced forming voltage in oxygen engineered HfO{sub 2} based resistive switching memories

    Energy Technology Data Exchange (ETDEWEB)

    Sharath, S. U., E-mail: sharath@oxide.tu-darmstadt.de; Kurian, J.; Komissinskiy, P.; Hildebrandt, E.; Alff, L. [Institute of Materials Science, Technische Universität Darmstadt, 64287 Darmstadt (Germany); Bertaud, T.; Walczyk, C.; Calka, P. [IHP, Im Technologiepark 25, 15236 Frankfurt Oder (Germany); Schroeder, T. [IHP, Im Technologiepark 25, 15236 Frankfurt Oder (Germany); Brandenburgische Technische Universität, Konrad-Zuse-Strasse 1, 03046 Cottbus (Germany)

    2014-08-18

    The conducting filament forming voltage of stoichiometric hafnium oxide based resistive switching layers increases linearly with layer thickness. Using strongly reduced oxygen deficient hafnium oxide thin films grown on polycrystalline TiN/Si(001) substrates, the thickness dependence of the forming voltage is strongly suppressed. Instead, an almost constant forming voltage of about 3 V is observed up to 200 nm layer thickness. This effect suggests that filament formation and switching occurs for all samples in an oxidized HfO{sub 2} surface layer of a few nanometer thickness while the highly oxygen deficient thin film itself merely serves as a oxygen vacancy reservoir.

  12. Characterization of electron beam deposited thin films of HfO2 and binary thin films of (HfO2:SiO2) by XRD and EXAFS measurements

    International Nuclear Information System (INIS)

    Das, N.C.; Sahoo, N.K.; Bhattacharyya, D.; Thakur, S.; Kamble, N.M.; Nanda, D.; Hazra, S.; Bal, J.K.; Lee, J.F.; Tai, Y.L.; Hsieh, C.A.

    2009-10-01

    In this report, we have discussed the microstructure and the local structure of composite thin films having varying hafnia and silica compositions and prepared by reactive electron beam evaporation. XRD and EXAFS studies have confirmed that the pure hafnium oxide thin film has crystalline microstructure whereas the films with finite hafnia and silica composition are amorphous. The result of EXAFS analysis has shown that the bond lengths as well as coordination numbers around hafnium atom change with the variation of hafnia and silica compositions in the thin film. Finally, change of bond lengths has been correlated with change of refractive index and band gap of the composite thin films. (author)

  13. Effect of zirconium purity on the glass-forming-ability and notch toughness of Cu{sub 43}Zr{sub 43}Al{sub 7}Be{sub 7}

    Energy Technology Data Exchange (ETDEWEB)

    Andersen, Laura M. [Department of NanoEngineering, University of California, San Diego, 9500 Gilman Drive, La Jolla, CA (United States); Hofmann, Douglas C. [Materials Development and Manufacturing Technology Group, NASA Jet Propulsion Laboratory/California Institute of Technology, MS 18-105, 4800 Oak Grove Dr. Pasadena, CA 91109 (United States); Vecchio, Kenneth S., E-mail: kvecchio@ucsd.edu [Department of NanoEngineering, University of California, San Diego, 9500 Gilman Drive, La Jolla, CA (United States)

    2016-09-30

    The effect of substituting standard grade zirconium lump (99.8% excluding up to 4% hafnium) for high purity zirconium crystal bar (99.5%) in a Cu{sub 43}Zr{sub 43}Al{sub 7}Be{sub 7} bulk metallic glass (BMG) is examined. The final hafnium content in the BMG specimens was found to range from 0 to 0.44 at%. Introducing low purity zirconium significantly decreased the glass-forming-ability and reduced the notch toughness of the BMG. In contrast, when adding high purity hafnium to Cu{sub 43}Zr{sub 43}Al{sub 7}Be{sub 7} made with high purity zirconium, no significant change in the glass-forming-ability or toughness was observed. This suggests that the introduction of low purity zirconium in BMGs creates a more complex response than a simple addition of hafnium. It is likely that other impurities in the material, such as oxygen, play a role in the complex crystallization kinetics and change in mechanical properties. The notch toughness was measured through four-point-bend tests, which showed a decrease in notch toughness from an average of ~53 MPa m{sup 1/2} for the high purity samples to an average of ~29 MPa m{sup 1/2} with full substitution of low purity zirconium. A similar decrease in glass-forming-ability and toughness is observed in commercially synthesized high purity Cu{sub 43}Zr{sub 43}Al{sub 7}Be{sub 7}. The large scale commercial process is expected to introduced some unintentional impurities, which decrease the properties of the BMG in the same way as the lower purity elements. Lastly, Weibull statistics are used to provide an analysis of variability in toughness for both ingots synthesized in a small laboratory arc-melter and those synthesized commercially.

  14. Development of new extraction agents for separation of rare radioactive elements

    International Nuclear Information System (INIS)

    Hala, J.; Navratil, O.; Prihoda, J.; Smola, J.

    1977-01-01

    Certain transition elements, such as rhodium and palladium may be recovered from waste solutions produced in spent fuel reprocessing. The extraction of palladium was studied using sulfur compounds of the sulfide and sulfoxide types and the effects were investigated of the individual factors on palladium distribution between the aqueous and the organic phases. The possibility of separating hafnium in the form of extractable complexes was tested on several systems. Studied in more detail were mainly the complexes of hafnium with pyrocatechol violet, xylenol orange, and tributyl phosphate. The extraction of other metals, mainly of scandium, europium and indium was investigated in detail in the system acid aqueous phase - organophosphinic acids solution in benzene. (L.K.)

  15. Spin distribution of evaporation residues formed in complete and incomplete fusion in 16O+154Sm system

    Science.gov (United States)

    Singh, D.; Linda, Sneha B.; Giri, Pankaj K.; Mahato, Amritraj; Tripathi, R.; Kumar, Harish; Afzal Ansari, M.; Sathik, N. P. M.; Ali, Rahbar; Kumar, Rakesh; Muralithar, S.; Singh, R. P.

    2017-11-01

    Spin distributions for several evaporation residues populated in the 16O+154Sm system have been measured at projectile energy ≈ 6.2 MeV/A by using the charged particle-γ-coincidence technique. The measured spin distributions of the evaporation residues populated through incomplete fusion associated with 'fast' α and 2α-emission channels are found to be entirely different from fusion-evaporation channels. It is observed that the mean input angular momentum for the evaporation residues formed in incomplete fusion channel is relatively higher than that observed for evaporation residues in complete fusion channels. The feeding intensity profile of evaporation residues populated through complete fusion and incomplete fusion have also been studied. The incomplete fusion channels are found to have narrow range feeding only for high spin states, while complete fusion channels are strongly fed over a broad spin range and widely populated. Comparison of present results with earlier data suggests that the mean input angular momentum values are relatively smaller for spherical target than that of deformed target using the same projectile and incident energy highlighting the role of target deformation in incomplete fusion dynamics.

  16. Spin distribution of evaporation residues formed in complete and incomplete fusion in 16O+154Sm system

    Directory of Open Access Journals (Sweden)

    D. Singh

    2017-11-01

    Full Text Available Spin distributions for several evaporation residues populated in the 16O+154Sm system have been measured at projectile energy ≈ 6.2 MeV/A by using the charged particle–γ-coincidence technique. The measured spin distributions of the evaporation residues populated through incomplete fusion associated with ‘fast’ α and 2α-emission channels are found to be entirely different from fusion–evaporation channels. It is observed that the mean input angular momentum for the evaporation residues formed in incomplete fusion channel is relatively higher than that observed for evaporation residues in complete fusion channels. The feeding intensity profile of evaporation residues populated through complete fusion and incomplete fusion have also been studied. The incomplete fusion channels are found to have narrow range feeding only for high spin states, while complete fusion channels are strongly fed over a broad spin range and widely populated. Comparison of present results with earlier data suggests that the mean input angular momentum values are relatively smaller for spherical target than that of deformed target using the same projectile and incident energy highlighting the role of target deformation in incomplete fusion dynamics.

  17. Novel Manufacturing Process for Unique Mixed Carbide Refractory Composites, Phase I

    Data.gov (United States)

    National Aeronautics and Space Administration — This STTR Phase I project will establish the feasibility of an innovative manufacturing process to fabricate a range of unique hafnium/silicon based carbide...

  18. Cobalt catalysts, and use thereof for the conversion of methanol and for fischer-tropsch synthesis, to produce hydrocarbons

    International Nuclear Information System (INIS)

    Mauldin, C.H.; Davis, S.M.; Arcuri, K.B.

    1988-01-01

    This patent describes a process useful for the conversion of methanol to hydrocarbons which comprises contacting the methanol at reaction conditions with a catalyst which comprises from about 2 percent to about 25 percent cobalt, based on the weight of the catalyst composition, composited with titania, or a titania-containing support, to which is added a zirconium, hafnium, cerium, or uranium promoter, the weight ratio of the zirconium, hafnium, cerium, or uranium metal:cobalt being greater than about 0.010:1; the reaction conditions being defined within ranges as follows: Methanol:H/sub 2/ ratio: greater than about 4:1, Space Velocities, Hr/sup -1/:about 0.1 to 10, Temperatures, 0 C.:about 150 to 350, Methanol Partial Pressure, psia: about 100 to 1000

  19. Ceramic component for M.H.D electrode

    International Nuclear Information System (INIS)

    Marchant, D.D.; Bates, J.L.

    1980-01-01

    A ceramic component which exhibits electrical conductivity down to near room temperatures has the formula: Hfsub(x)Insub(y)Asub(z)O 2 where x = 0.1 to 0.4, y = 0.3 to 0.6, z = 0.1 to 0.4 and A is a rare earth or yttrium. The rare earth may be Yb, Tb, Pr or Ce. The component is suitable for use in the fabrication of MHD electrodes or as the current lead-out portion of a composite electrode with other ceramic components. An MHD electrode comprises a cap of a known ceramic, e.g. stabilised zirconium or hafnium oxide or terbium stabilised hafnium, a current lead-out ceramic according to the invention, and a copper frame. (author)

  20. 40 CFR 302.6 - Notification requirements.

    Science.gov (United States)

    2010-07-01

    ..., phosphate, tin, zircon, hafnium, vanadium, monazite, and rare earth mines. Land disturbance incidental to..., chromium, copper, lead, nickel, selenium, silver, thallium, or zinc is not required if the mean diameter of...

  1. Electrochemical investigations of ion-implanted oxide films

    International Nuclear Information System (INIS)

    Schultze, J.W.; Danzfuss, B.; Meyer, O.; Stimming, U.

    1985-01-01

    Oxide films (passive films) of 40-50 nm thickness were prepared by anodic polarization of hafnium and titanium electrodes up to 20 V. Multiple-energy ion implantation of palladium, iron and xenon was used in order to obtain modified films with constant concentration profiles of the implanted ions. Rutherford backscattering, X-ray photoelectron spectroscopy measurements and electrochemical charging curves prove the presence of implanted ions, but electrochemical and photoelectrochemical measurements indicate that the dominating effect of ion implantation is the disordering of the oxide film. The capacity of hafnium electrodes increases as a result of an increase in the dielectric constant D. For titanium the Schottky-Mott analysis shows that ion implantation causes an increase in D and the donor concentration N. Additional electronic states in the band gap which are created by the implantation improve the conductivity of the semiconducting or insulating films. This is seen in the enhancement of electron transfer reactions and its disappearance during repassivation and annealing. Energy changes in the band gap are derived from photoelectrochemical measurements; the absorption edge of hafnium oxide films decreases by approximately 2 eV because of ion implantation, but it stays almost constant for titanium oxide films. All changes in electrochemical behavior caused by ion implantation show little variation with the nature of the implanted ion. Hence the dominating effect seems to be a disordering of the oxide. (Auth.)

  2. Microstructural characterization of as-cast hf-b alloys

    Directory of Open Access Journals (Sweden)

    João Carlos Jânio Gigolotti

    2012-04-01

    Full Text Available An accurate knowledge of several metal-boron phase diagrams is important to evaluation of higher order systems such as metal-silicon-boron ternaries. The refinement and reassessment of phase diagram data is a continuous work, thus the reevaluation of metal-boron systems provides the possibility to confirm previous data from an investigation using higher purity materials and better analytical techniques. This work presents results of rigorous microstructural characterization of as-cast hafnium-boron alloys which are significant to assess the liquid composition associated to most of the invariant reactions of this system. Alloys were prepared by arc melting high purity hafnium (minimum 99.8% and boron (minimum 99.5% slices under argon atmosphere in water-cooled copper crucible with non consumable tungsten electrode and titanium getter. The phases were identified by scanning electron microscopy, using back-scattered electron image mode and X-ray diffraction. In general, a good agreement was found between our data and those from the currently accepted Hafnium-Boron phase diagram. The phases identified are αHfSS and B-RhomSS, the intermediate compounds HfB and HfB2 and the liquide L. The reactions are the eutectic L ⇔ αHfSS + HfB and L ⇔ HfB2 + B-Rhom, the peritectic L + HfB2 ⇔ HfB and the congruent formation of HfB2.

  3. WWER-440 local power peaking experiment with/without Hf inserts in the LR-0 reactor

    International Nuclear Information System (INIS)

    Josek, R.; Hudec, F.; Rypar, V.

    2006-01-01

    One of the known issues of the WWER-440 reactors is the control rod coupler induced power peaking in the neighbouring fuel assemblies. The effect has been discovered some years ago and is believed to be the cause of several fuel failures during operation in WWER-440 reactors. The effect itself is due to over-moderation and small absorption in the region of control rod coupler, leading to increase in thermal neutron flux and hence to power flare-up in the neighbouring fuel pins. The fuel vendor tackled the problem by attaching hafnium inserts on the inside of the control assembly box. The experiment performed in the LR-0 reactor was focused on the axial and radial power profiles in the vicinity of the control assembly with and without the hafnium inserts. The results of measurements with zero boron concentration are presented. The hafnium insert causes a decrease in peaking factor of about 30% in selected pins close to the control assembly. The measurements are compared with calculations performed with the MCNP-4C code. The compared variables are: the axial fission density distributions; peking factors and peaking factor decrease due to Hf insert. The MCNP results are accurate with respect to the experimental results. A series of benchmarks is being prepared on the basis of these measurements

  4. Design of thermoelectrically highly efficient Heusler compounds using phase separations and nano-composites under an economic point of view

    Science.gov (United States)

    Balke, Benjamin

    Half-Heusler (HH) compounds are one of the most promising candidates for thermoelectric materials for automotive and industrial waste heat recovery applications. In this talk, I will give an overview about our recent investigations of phase separations in HH thermoelectrics, focusing on the ternary system TiNiSn-ZrNiSn-HfNiSn. I will show how we adapted this knowledge to design a p-type HH compound which exhibits a ZT that is increased by 130% compared to the best published bulk p-type Heusler. I will also present how we used the phase separation to design thermoelectric highly efficient nano-composites of different single-phase materials. Since the price for Hafnium doubled within the last year, our research focused on the design of HH compounds without Hafnium. I will present a very recent calculation on ZT per Euro and efficiency per Euro for various materials followed by our latest very promising results for n-type Heusler compunds without Hafnium resulting in 20 times higher ZT/Euro values. These results strongly underline the importance of phase separations as a powerful tool for designing highly efficient materials for thermoelectric applications that fulfill the industrial demands for a thermoelectric converter. The author gratefully acknowledges financial support by the thermoHEUSLER2 Project (Project No. 19U15006F) of the German Federal Ministry of Economics and Technology (BMWi).

  5. Mesoporous TiO2 powders as host matrices for iron nanoparticles. Effect of the preparation procedure and doping with Hf

    Czech Academy of Sciences Publication Activity Database

    Dimitrov, M.; Ivanova, R.; Velinov, N.; Henych, Jiří; Slušná, Michaela; Štengl, Václav; Tolasz, Jakub; Mitov, I.; Tsoncheva, T.

    2016-01-01

    Roč. 7, JUL (2016), s. 56-63 ISSN 2352-507X Institutional support: RVO:61388980 Keywords : Mesoporous titania * Hafnium doping * Iron modification * Ethyl acetate oxidation * Methanol decomposition Subject RIV: CA - Inorganic Chemistry

  6. Cathodoluminescence of Irradiated Hafnium Dioxide

    Science.gov (United States)

    2011-03-01

    Martin and Michael Rhoby for their hard work in fixing assorted problems that cropped up during the course of my thesis work. Emily A. Purcell...Cathodoluminescence Microscopy of Inorganic Solids. New York: Plenum Press, 1990. [13] D. Drouin, A. R. Couture, D. Joly , X. Tastet, V. Aimez and R. Gauvin

  7. Zirconium Zr and hafnium Hf

    International Nuclear Information System (INIS)

    Busev, A.I.; Tiptsova, V.G.; Ivanov, V.M.

    1978-01-01

    The basic methods for extracting and determining Zr(4) and Hf(4) are described. Diantipyrinemethane and its alkyl homologs selectively extract Zr and Hf from HNO 3 solutions in the presence of nitrates. Zr is selectively extracted with tetraethyldiamide of heptyl phosphoric acid (in benzene) as well as with 2-thenoyltrifluoroacetone (in an acid). The latter reagents is suitable for rapid determination of 95 Zr in a mixture with 95 Nb and other fragments. The complexometric determination of Zr is based on formation of a stable complex of Zr with EDTA. The titration is carried out in the presence of n-sulfobenzene-azo-pyrocatechol, eriochrome black T. The determination is hindered by Hf, fluoride-, phosphate-, oxalate- and tartrate-ions. The method is used for determining Zr in zircon and eudialyte ore. Zr is determined photometrically with the aid of xylenol orange, arsenazo 3 and pyrocatechol violet (in phosphorites). Hf is determined in the presence of Zr photometrically with the aid of xylenol orange or methyl-thymol blue. The method is based on Zr being masked with hydrogen peroxide in the presence of sulfate-ions

  8. Alkali metal hafnium oxide scintillators

    Science.gov (United States)

    Bourret-Courchesne, Edith; Derenzo, Stephen E.; Taylor, Scott Edward

    2018-05-08

    The present invention provides for a composition comprising an inorganic scintillator comprising an alkali metal hafnate, optionally cerium-doped, having the formula A2HfO3:Ce; wherein A is an alkali metal having a valence of 1, such as Li or Na; and the molar percent of cerium is 0% to 100%. The alkali metal hafnate are scintillators and produce a bright luminescence upon irradiation by a suitable radiation.

  9. High-pressure torsion of hafnium

    International Nuclear Information System (INIS)

    Edalati, Kaveh; Horita, Zenji; Mine, Yoji

    2010-01-01

    Pure Hf (99.99%) is processed by high-pressure torsion (HPT) under pressures of 4 and 30 GPa to form an ultrafine-grained structure with a gain size of ∼180 nm. X-ray diffraction analysis shows that, unlike Ti and Zr, no ω phase formation is detected after HPT processing even under a pressure of 30 GPa. A hydride formation is detected after straining at the pressure of 4 GPa. The hydride phase decomposes either by application of a higher pressure as 30 GPa or by unloading for prolong time after HPT processing. Microhardness, tensile and bending tests show that a high hardness (360 Hv) and an appreciable ductility (8%) as well as high tensile and bending strength (1.15 and 2.75 GPa, respectively) are achieved following the high-pressure torsion.

  10. X-ray target with substrate of molybdenum alloy

    International Nuclear Information System (INIS)

    Hirsch, H.H.

    1980-01-01

    Rotary targets for x-ray tubes are provided comprising a molybdenum base body alloyed with a stabilizing proportion of iron, silicon, cobalt, tantalum, niobium, hafnium, stable metal oxide, or a mixture of the preceding

  11. Determination of optimum Si excess concentration in Er-doped Si-rich SiO2 for optical amplification at 1.54 μm

    International Nuclear Information System (INIS)

    Savchyn, Oleksandr; Coffey, Kevin R.; Kik, Pieter G.

    2010-01-01

    The presence of indirect Er 3+ excitation in Si-rich SiO 2 is demonstrated for Si-excess concentrations in the range of 2.5-37 at. %. The Si excess concentration providing the highest density of sensitized Er 3+ ions is demonstrated to be relatively insensitive to the presence of Si nanocrystals and is found to be ∼14.5 at. % for samples without Si nanocrystals (annealed at 600 deg. C) and ∼11.5 at. % for samples with Si nanocrystals (annealed at 1100 deg. C). The observed optimum is attributed to an increase in the density of Si-related sensitizers as the Si concentration is increased, with subsequent deactivation and removal of these sensitizers at high Si concentrations. The optimized Si excess concentration is predicted to generate maximum Er-related gain at 1.54 μm in devices based on Er-doped Si-rich SiO 2 .

  12. Dual function of the hemagglutinin H5 fused to chicken CD154 in a potential strategy of DIVA against avian influenza disease: preliminary study

    Directory of Open Access Journals (Sweden)

    A.G. Pose

    2015-09-01

    Full Text Available In this study we demonstrated that the vaccine candidate against avian influenza virus H5N1 based on the hemagglutinin H5 (HA fused to the chicken CD154 (HACD can also be used for differentiating infected from vaccinated animals (DIVA. As the strategy of DIVA requires at least two proteins, we obtained a variant of the nucleoprotein (NP49-375 in E. coli. After its purification by IMAC, the competence of the proteins NP49-375 and HACD as coating antigens in indirect ELISA assays were tested by using the sera of chickens immunized with the proteins HA and HACD and the reference sera from several avian influenza subtypes. Together with these sera, the sera from different species of birds and the sera of chickens infected with other avian viral diseases were analyzed by competition ELISA assays coated with the proteins NP49-375 and HACD. The results showed that the segment CD154 in the chimeric protein HACD did not interfere with the recognition of the molecule HA by its specific antibodies. Also, we observed variable detection levels when the reference sera were analyzed in the ELISA plates coated with the protein NP49-375. Moreover, only the antibodies of the reference serum subtype H5 were detected in the ELISA plates coated with the protein HACD. The competition ELISA assays showed percentages of inhibition of 88-91% for the positives sera and less than 20% for the negative sera. We fixed the cut-off value of these assays at 25%. No antibody detection was observed in the sera from different species of birds or the sera of chickens infected with other avian viral diseases. This study supported the fact that the ELISA assays using the proteins NP49-375 and HACD could be valuable tools for avian influenza surveillance and as a strategy of DIVA for counteracting the highly pathogenic avian influenza virus H5N1 outbreaks.

  13. Dual function of the hemagglutinin H5 fused to chicken CD154 in a potential strategy of DIVA against avian influenza disease: preliminary study.

    Science.gov (United States)

    Pose, A G; Rodríguez, E S; Méndez, A C; Gómez, J N; Redondo, A V; Rodríguez, E R; Ramos, E M G; Gutiérrez, A Á; Moltó, M P R; Roche, D G; Ugalde, Y S; López, A M

    2015-01-01

    In this study we demonstrated that the vaccine candidate against avian influenza virus H5N1 based on the hemagglutinin H5 (HA) fused to the chicken CD154 (HACD) can also be used for differentiating infected from vaccinated animals (DIVA). As the strategy of DIVA requires at least two proteins, we obtained a variant of the nucleoprotein (NP49-375) in E. coli. After its purification by IMAC, the competence of the proteins NP49-375 and HACD as coating antigens in indirect ELISA assays were tested by using the sera of chickens immunized with the proteins HA and HACD and the reference sera from several avian influenza subtypes. Together with these sera, the sera from different species of birds and the sera of chickens infected with other avian viral diseases were analyzed by competition ELISA assays coated with the proteins NP49-375 and HACD. The results showed that the segment CD154 in the chimeric protein HACD did not interfere with the recognition of the molecule HA by its specific antibodies. Also, we observed variable detection levels when the reference sera were analyzed in the ELISA plates coated with the protein NP49-375. Moreover, only the antibodies of the reference serum subtype H5 were detected in the ELISA plates coated with the protein HACD. The competition ELISA assays showed percentages of inhibition of 88-91% for the positives sera and less than 20% for the negative sera. We fixed the cut-off value of these assays at 25%. No antibody detection was observed in the sera from different species of birds or the sera of chickens infected with other avian viral diseases. This study supported the fact that the ELISA assays using the proteins NP49-375 and HACD could be valuable tools for avian influenza surveillance and as a strategy of DIVA for counteracting the highly pathogenic avian influenza virus H5N1 outbreaks.

  14. Control rod

    International Nuclear Information System (INIS)

    Igarashi, Takao; Sugawara, Satoshi; Yoshimoto, Yuichiro; Saito, Shozo; Fukumoto, Takashi.

    1987-01-01

    Purpose: To reduce the weight and thereby obtain satisfactory operationability of control rods by combining absorbing nuclear chain type neutron absorbers and conventional type neutron absorbers in the axial direction of blades. Constitution: Neutron absorber rods and long life type neutron absorber rods are disposed in a tie rod and a sheath. The neutron absorber rod comprises a poison tube made of stainless steels and packed with B 4 C powder. The long life type neutron absorber rod is prepared by packing B-10 enriched boron carbide powder into a hafnium metal rod, hafnium pipe, europium and stainless made poison tube. Since the long life type absorber rod uses HF as the absorbing nuclear chain type neutron absorber, it absorbs neutrons to form new neutron absorbers to increase the nuclear life. (Yoshino, Y.)

  15. Thermodynamic study of the MWG system/components and measurement of the oxygen partial pressure in the heat source capsule

    International Nuclear Information System (INIS)

    David, D.J.

    1980-01-01

    A thermodynamic study of the Milliwatt Generator heat source capsule was performed to determine the effects of the oxide fuel on container materials at elevated temperatures in order to evaluate the factors affecting embrittlement of T-111 alloy. The study indicates that relatively slow oxidation of the T-111 of the capsule occurs during pretreatment. Yttrium added to the 238 PuO 2 fuel charge is functioning in its designed role as an oxygen getter and is stabilizing at an O/Pu ratio of 1.75. The free energy of formation of hafnium oxide has been measured and found to be -70632 cal/mole; this suggests that the ability of hafnium to strongly function as an oxygen getter may be largely determined by the kinetics, and the free energy may play a lesser role

  16. Development of Advanced Environmental Barrier Coatings for SiC/SiC Ceramic Matrix Composites: Path Toward 2700 F Temperature Capability and Beyond

    Science.gov (United States)

    Zhu, Dongming; Harder, Bryan; Hurst, Janet B.; Good, Brian; Costa, Gustavo; Bhatt, Ramakrishna T.; Fox, Dennis S.

    2017-01-01

    Advanced environmental barrier coating systems for SiC-SiC Ceramic Matrix Composite (CMC) turbine and combustor hot section components are currently being developed to meet future turbine engine emission and performance goals. One of the significant coating development challenges is to achieve prime-reliant environmental barrier coating systems to meet the future 2700F EBC-CMC temperature stability and environmental durability requirements. This presentation will emphasize recent NASA environmental barrier coating system testing and down-selects, particularly the development path and properties towards 2700-3000F durability goals by using NASA hafnium-hafnia-rare earth-silicon-silicate composition EBC systems for the SiC-SiC CMC turbine component applications. Advanced hafnium-based compositions for enabling next generation EBC and CMCs capabilities towards ultra-high temperature ceramic coating systems will also be briefly mentioned.

  17. 10 CFR Appendix L to Part 110 - Illustrative List of Byproduct Materials Under NRC Export/Import Licensing Authority a

    Science.gov (United States)

    2010-01-01

    ... material produced, extracted, or converted for use for a commercial, medical, or research activity...) Gallium 72 (Ga 72) Germanium 68 (Ge 68) Germanium 71 (Ge 71) Gold 198 (Au 198) Gold 199 (Au 199) Hafnium...

  18. Effect of ultrasmall Au–Ag aggregates formed by ion implantation in Er-implanted silica on the 1.54 μm Er{sup 3+} luminescence

    Energy Technology Data Exchange (ETDEWEB)

    Maurizio, C., E-mail: chiara.maurizio@unipd.it [Physics and Astronomy Department, University of Padova, Via Marzolo 8, 35131 Padova (Italy); Cesca, T. [Physics and Astronomy Department, University of Padova, Via Marzolo 8, 35131 Padova (Italy); Trapananti, A. [CNR-IOM c/o European Synchrotron Radiation Facility, B.P. 220, F-38043 Grenoble (France); Kalinic, B.; Scian, C.; Mazzoldi, P. [Physics and Astronomy Department, University of Padova, Via Marzolo 8, 35131 Padova (Italy); Battaglin, G. [Department of Molecular Sciences and Nanosystems, Ca’ Foscari University of Venice, Dorsoduro 2137, I-30123 Venice (Italy); Mattei, G. [Physics and Astronomy Department, University of Padova, Via Marzolo 8, 35131 Padova (Italy)

    2014-05-01

    Multiple implantations of Au and Ag ions in pure silica and Er-doped silica matrices have been performed to promote the formation of small Au–Ag alloy clusters. Upon annealing in N{sub 2} atmosphere at 600 °C the structural investigation based on X-ray absorption spectroscopy at Au L{sub 3}-edge detected for both cases the formation of Au–Ag alloy clusters, whose size is likely below 1 nm. The alloy composition is rich in Au; a minor part of Au atoms remains dispersed into the matrix and oxidized. In the Er-doped silica, the presence of these small alloy aggregates promotes a strong enhancement of the Er{sup 3+} luminescence at 1.54 μm, that is more marked with respect to similarly produced layers where only pure Au sub-nanometer clusters were present.

  19. Hafnium and neodymium isotopes and REY distribution in the truly dissolved, nanoparticulate/colloidal and suspended loads of rivers in the Amazon Basin, Brazil

    Science.gov (United States)

    Merschel, Gila; Bau, Michael; Schmidt, Katja; Münker, Carsten; Dantas, Elton L.

    2017-09-01

    Radiogenic isotopes in river sediments and river waters have been widely used in provenance studies, as these samples naturally integrate the geology/chemistry of the entire catchment. While the Hf and Nd isotope systems are coupled during igneous processes, they are decoupled during supergene processes at the Earth's surface, which is reflected by the isotope composition of riverine sediments. We present the first data for both Hf and Nd isotope compositions of the dissolved (0.2 μm-filtrates rich in nanoparticles and colloids, NPCs) and the truly dissolved (1 kDa-ultrafiltrates) load of rivers. Hafnium and Nd isotope compositions and concentrations of the Rare Earths and Yttrium (REY) and Hf were determined for suspended particles (>0.2 μm) as well as for the dissolved and the truly dissolved load of the Rio Solimões, the Amazon's largest tributary draining the Andes, and of the Rio Negro, an organic NPC- and particle-rich river draining the rainforest of northern Amazonia. We also analyzed the Nd isotope compositions of suspended sediments and 0.2 μm-filtered water samples from the Amazon River and its tributaries Rio Tapajos, Rio Xingu and Rio Jari. Our novel results clearly show that the decoupling of the Hf and Nd isotope systems is related to incongruent weathering processes on the continent, as this decoupling can already be observed in the different Hf and Nd pools, i.e. in the particulate, the NPC-dominated dissolved and the truly dissolved load of rivers. In the Rio Negro and Rio Solimões, a strong particle size-dependent difference in Hf isotope composition is observed. Values of εHf become more radiogenic as filter poresize decreases, which can be related to the density- and size-dependent distribution of Hf-rich minerals, e.g. zircons, and their absence from the truly dissolved pool. In contrast, the Nd isotope composition of Amazonian river waters reflects that of their catchment geology. Tributaries draining the Precambrian Brazilian and

  20. Fabrication of cermet bearings for the control system of a high temperature lithium cooled nuclear reactor

    Science.gov (United States)

    Yacobucci, H. G.; Heestand, R. L.; Kizer, D. E.

    1973-01-01

    The techniques used to fabricate cermet bearings for the fueled control drums of a liquid metal cooled reference-design reactor concept are presented. The bearings were designed for operation in lithium for as long as 5 years at temperatures to 1205 C. Two sets of bearings were fabricated from a hafnium carbide - 8-wt. % molybdenum - 2-wt. % niobium carbide cermet, and two sets were fabricated from a hafnium nitride - 10-wt. % tungsten cermet. Procedures were developed for synthesizing the material in high purity inert-atmosphere glove boxes to minimize oxygen content in order to enhance corrosion resistance. Techniques were developed for pressing cylindrical billets to conserve materials and to reduce machining requirements. Finishing was accomplished by a combination of diamond grinding, electrodischarge machining, and diamond lapping. Samples were characterized in respect to composition, impurity level, lattice parameter, microstructure and density.